A recent executive order issued by President Joe Biden seeks to establish "new standards for AI safety and security" while addressing consumer privacy concerns and promoting innovation. Georgia Tech experts have examined the key elements of the order and offer their thoughts on its scope and what comes next.  

A Precautionary Tale 

The order calls for the development of standards, tools, and tests to ensure the safe use of AI. From voice scams and phishing campaigns to larger-scale threats, the technology’s potential dangers have been widely documented. But Margaret Kosal, associate professor in the Ivan Allen College of Liberal Arts, says that additional context is often needed to dispel hysteria. 

"No one is going to be hooking up AI to launch nuclear weapons, but AI capabilities may enable targeting, or enable the command and control and the decision-making time to be compressed,” she said.  
 
The order will create an AI Safety and Security Board tasked with addressing critical threats. Companies developing foundation models that "pose a serious risk to national security, national economic security, or national public health and safety” will be required to notify the federal government when training the model and required to share the results of all red-team safety tests — a simulated cyberattack to test a system's defenses.  

Since the launch of ChatGPT in 2022, a CNBC report details a 1,267% rise in phishing emails. Srijan Kumar, assistant professor in the College of Computing, attributes the increase to the technology's availability and an inability to rein in "bad actors."  

He says these scams will only continue to get more sophisticated and personalized. They “can be created by knowing what you might be willing to fall prey to versus what I might fall prey to,” said Kumar, whose systems have influenced misinformation detection on sites like X (formerly Twitter) and Wikipedia. “AI is not going to autonomously do all of those bad things, but this order can ensure there are consequences for people who misuse it.”  

A Delicate Balance 

Building an AI platform requires large amounts of data regardless of its intended application. Two primary goals of the executive order are protecting privacy and advancing equity.  

To protect personal data, the order tasks Congress with evaluating how agencies collect and use commercially available information and address algorithmic discrimination.  

Acknowledging that everyone should be allowed to have their voice represented in the outputs of AI data sets, Deven Desai, associate professor in the Scheller College of Business, noted, "There are people who don't want to be part of data sets, which is their right, but this means their voices won't be reflected in the outputs.”   

The order also includes sections to address intellectual property concerns among inventors and creators, though legal challenges will likely set new precedents in the years ahead.  

When that time comes, Kosal says that defining “theft” in the context of AI becomes the true challenge and that, ultimately, money will play a significant role. "If you spit out a Harry Potter book and read it yourself, nobody will care. It's when you start selling it to make money, and you don't share proceeds with the original people, then it becomes an issue," she said.   

What Does AI-Generated Mean? 

The order instructs the Department of Commerce to develop guidelines for content authentication and watermarking to label AI-generated content. Desai questions what it means for something to be truly created by AI.  

An important distinction lies between using AI to assist a writer in organizing their thoughts and using the technology to generate content. He likens the trend to the music industry in the 1980s.  

"Synthesizers really changed people's ability to generate music and, for a while, people thought that was horrible. They can just program the music. They're not. I am still the human responsible for that music, or that article in this case, so what is the point of the label?" he asks. 

As AI assistance becomes commonplace in content creation, trusting the source of information is increasingly important. Recently, articles published on Sports Illustrated's website featured AI-generated content provided by a third-party company that had used a machine to write the content and create fake bylines. Sports Illustrated, which may not have known of the problem, ran the material without disclosure to readers. CEO Ross Levinsohn was ousted shortly after the story broke.  

“Perhaps if the third party had disclosed its use of AI software, SI would have been able to assess how much AI was used and then chosen not to run the material, or to run it with a disclaimer that AI helped write the material,” Desai said. "Of course, even if they label the content as AI-generated, a reader still won't know exactly how much of the content came from AI or a human.” 

AI and the Workforce 

As AI systems and models become more sophisticated, workers may become more concerned about being replaced. To counteract these concerns, the order calls for a study to examine AI’s potential impact on labor markets and investments in workforce training efforts.  

Kumar compares the rise of AI to similar technological innovations throughout history and sees it as an opportunity for workers and industries to adapt. "It's less a matter of AI replacing workers and more of reskilling people to use the new technology. It's no different from when assembly lines in the auto industry were created."  

Promoting Innovation and Competition 

The power to harness the full potential of AI has initiated a race to the top. Desai believes that part of the executive order providing resources to smaller developers can help level the playing field.   

"There is a possibility here for markets to open up. Current players using models that weren't built with transparency in mind might struggle, but maybe that's OK." 

The issue of reliability and transparency comes into focus for Desai, especially as it relates to government usage of AI. The order calls on agencies to "acquire specified AI products and services faster, more cheaply, and more effectively through more rapid and efficient contracting."  

When taxpayer dollars are at stake, government can’t afford to trust a technology it doesn’t fully understand — a topic Desai has explored elsewhere. "You can’t just say, ‘We don’t know how it works, but we trust it.’ That’s not going to work. So that’s where there may be a slowdown in the government’s ability to use private sector software if they can’t explain how the thing works and to show that it doesn’t have discriminatory issues.” 

What's Next 

Promoting and policing the safe use of AI cannot be done independently. Georgia Tech experts agree that participation on a global scale is necessary. To that end, the European Union will unveil its comprehensive EU AI Act, which includes a similar framework to the president's executive order.  

Due to the evolving nature of AI, the executive order or the EU's actions will not be all-encompassing. Law often lags behind technology, but Kosal points out that it's crucial to think beyond what currently exists when crafting policy.  

Experts also agree that AI cannot be regulated or governed through a single document and that this order is likely the first in a series of policymaking moves. Kosal sees tremendous opportunity with the innovation surrounding AI but hopes the growing fear of its rise does not usher in another AI winter, in which interest and research funding fade. 

With the support of a four-year, $2.5 million grant from the National Institutes of Health, Brooks Lindsey will lead a team developing an imaging system to fill these gaps and guide treatment based on assessing the risk of heart attack in patients with coronary artery disease.

Many of those patients are treated via a minimally-invasive procedure that places a stent to re-open arteries that have become narrowed with plaques. Partially occluded coronary arteries can result in heart attack in some of these patients. However, other patients have a similar blockage but have stable disease and do not require intervention. The challenge is deciding which patients are which.

“In the cardiac catheterization lab where these procedures are performed, there are a number of separate approaches for quantifying functional markers, such as local blood pressure, blood flow velocity, and plaque composition. However, all of these tools function independently and in isolation from one another,” said Lindsey, assistant professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. “Most are one-dimensional measurements, which makes it difficult to measure everything going on in the complex, 3D, local biomechanical environment. This includes tissue and plaque mechanical properties, artery geometry, and hemodynamics, all of which vary dynamically as the heart beats.”

While current tools can measure blood flow velocity or blood pressure and characterize plaque composition independently, all of these factors together contribute to the likelihood of plaque rupture and heart attack. No current method can acquire all this information with spatial and temporal information intact.

Lindsey’s lab will address this gap by developing a tiny ultrasound imaging device approximately 1 millimeter in diameter to measure these properties in 3D from the tip of the catheter during procedures in the cardiac catheterization lab. Their approach will be designed to allow simultaneous measurement of blood flow velocity, mechanical properties of tissue, and artery geometry for the first time.

“More than 1 million cardiac catheterizations are performed each year in the U.S.,” Lindsey said. “Even patients who ultimately do not require intervention undergo diagnostic catheterization, but there is no way to measure all the properties simultaneously. The goal of this project is to develop a system that uses ultrasound on the tip of catheter to give cardiologists a complete picture of the patient’s individual anatomy and physiology, including dynamic behavior in coronary arteries as the heart beats. This imaging information, in turn, allows development of improved computational models of coronary arteries in health and disease.”

Lindsey will lead engineering efforts, including development of the imaging device and algorithms to quantify hemodynamics. Clinical aspects of the project will be handled by Habib Samady, a cardiologist at Northeast Georgia Medical Center in Gainesville who is an expert in imaging hemodynamics in clinical practice. Alessandro Veneziani, professor in Emory’s Department of Mathematics and Computer Science, will lead computational modeling efforts. Muralidhar Padala, director of the Structural Heart Research & Innovation Program and associate professor in Emory’s Division of Cardiothoracic Surgery, will lead testing in coronary artery disease models. Coulter BME Professor John Oshinski will provide expertise in imaging-derived fluid dynamics.

A multi-institutional, international team of researchers led by the lab of Woon-Hong Yeo at the Georgia Institute of Technology combined wireless soft scalp electronics and virtual reality in a BMI system that allows the user to imagine an action and wirelessly control a wheelchair or robotic arm.

The team, which included researchers from the University of Kent (United Kingdom) and Yonsei University (Republic of Korea), describes the new motor imagery-based BMI system this month in the journal Advanced Science.

“The major advantage of this system to the user, compared to what currently exists, is that it is soft and comfortable to wear, and doesn’t have any wires,” said Yeo, associate professor on the George W. Woodruff School of Mechanical Engineering.

BMI systems are a rehabilitation technology that analyzes a person’s brain signals and translates that neural activity into commands, turning intentions into actions. The most common non-invasive method for acquiring those signals is ElectroEncephaloGraphy, EEG, which typically requires a cumbersome electrode skull cap and a tangled web of wires.

These devices generally rely heavily on gels and pastes to help maintain skin contact, require extensive set-up times, are generally inconvenient and uncomfortable to use. The devices also often suffer from poor signal acquisition due to material degradation or motion artifacts – the ancillary “noise” which may be caused by something like teeth grinding or eye blinking. This noise shows up in brain-data and must be filtered out.

The portable EEG system Yeo designed, integrating imperceptible microneedle electrodes with soft wireless circuits, offers improved signal acquisition. Accurately measuring those brain signals is critical to determining what actions a user wants to perform, so the team integrated a powerful machine learning algorithm and  virtual reality component to address that challenge.

The new system was tested with four human subjects, but hasn’t been studied with disabled individuals yet.

“This is just a first demonstration, but we’re thrilled with what we have seen,” noted Yeo, Director of Georgia Tech’s Center for Human-Centric Interfaces and Engineering under the Institute for Electronics and Nanotechnology, and a member of the Petit Institute for Bioengineering and Bioscience.

New Paradigm

Yeo’s team originally introduced soft, wearable EEG brain-machine interface in a 2019 study published in the Nature Machine Intelligence. The lead author of that work, Musa Mahmood, was also the lead author of the team’s new research paper.

“This new brain-machine interface uses an entirely different paradigm, involving imagined motor actions, such as grasping with either hand, which frees the subject from having to look at too much stimuli,” said Mahmood, a Ph. D. student in Yeo’s lab.

In the 2021 study, users demonstrated accurate control of virtual reality exercises using their thoughts – their motor imagery. The visual cues enhance the process for both the user and the researchers gathering information.

“The virtual prompts have proven to be very helpful,” Yeo said. “They speed up and improve user engagement and accuracy. And we were able to record continuous, high-quality motor imagery activity.”

According to Mahmood, future work on the system will focus on optimizing electrode placement and more advanced integration of stimulus-based EEG, using what they’ve learned from the last two studies.

This research was supported by the National Institutes of Health (NIH R21AG064309), the Center Grant (Human-Centric Interfaces and Engineering) at Georgia Tech, the National Research Foundation of Korea (NRF-2018M3A7B4071109 and NRF-2019R1A2C2086085) and Yonsei-KIST Convergence Research Program. Georgia Tech has a pending patent application related to the work described in this paper.

Citation: Musa Mahmood, et al., “Wireless Soft Scalp Electronics and Virtual Reality System for Motor Imagery-based Brain-Machine Interfaces.” (Advanced Science, July 2021)

Links

Woon-Hong Yeo

“Wireless Soft Scalp Electronics and Virtual Reality System for Motor Imagery-based Brain-Machine Interfaces.”

Center for Human-Centric Interfaces and Engineering

Petit Institute for Bioengineering and Bioscience     

George W. Woodruff School of Mechanical Engineering

Researchers from the Georgia Institute of Technology and Emory University found that chromatin compaction is required for proper embryonic stem cell differentiation to occur. Chromatin, which is composed of histone proteins and DNA, packages DNA into a smaller volume so that it fits inside a cell. 

A study published on May 10, 2012 in the journal PLoS Genetics found that embryonic stem cells lacking several histone H1 subtypes and exhibiting reduced chromatin compaction suffered from impaired differentiation under multiple scenarios and demonstrated inefficiency in silencing genes that must be suppressed to induce differentiation.

“While researchers have observed that embryonic stem cells exhibit a relaxed, open chromatin structure and differentiated cells exhibit a compact chromatin structure, our study is the first to show that this compaction is not a mere consequence of the differentiation process but is instead a necessity for differentiation to proceed normally,” said Yuhong Fan, an assistant professor in the Georgia Tech School of Biology.

Fan and Todd McDevitt, an associate professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, led the study with assistance from Georgia Tech graduate students Yunzhe Zhang and Kaixiang Cao, research technician Marissa Cooke, and postdoctoral fellow Shiraj Panjwani.

The work was supported by the National Institutes of Health’s National Institute of General Medical Sciences (NIGMS), the National Science Foundation, a Georgia Cancer Coalition Distinguished Scholar Award, and a Johnson & Johnson/Georgia Tech Healthcare Innovation Award.

To investigate the impact of linker histones and chromatin folding on stem cell differentiation, the researchers used embryonic stem cells that lacked three subtypes of linker histone H1 -- H1c, H1d and H1e -- which is the structural protein that facilitates the folding of chromatin into a higher-order structure. They found that the expression levels of these H1 subtypes increased during embryonic stem cell differentiation, and embryonic stem cells lacking these H1s resisted spontaneous differentiation for a prolonged time, showed impairment during embryoid body differentiation and were unsuccessful in forming a high-quality network of neural cells.

“This study has uncovered a new, regulatory function for histone H1, a protein known mostly for its role as a structural component of chromosomes,” said Anthony Carter, who oversees epigenetics grants at NIGMS.  “By showing that H1 plays a part in controlling genes that direct embryonic stem cell differentiation, the study expands our understanding of H1’s function and offers valuable new insights into the cellular processes that induce stem cells to change into specific cell types.”

During spontaneous differentiation, the majority of the H1 triple-knockout embryonic stem cells studied by the researchers retained a tightly packed colony structure typical of undifferentiated cells and expressed high levels of Oct4 for a prolonged time. Oct4 is a pluripotency gene that maintains an embryonic stem cell’s ability to self-renew and must be suppressed to induce differentiation.

“H1 depletion impaired the suppression of the Oct4 and Nanog pluripotency genes, suggesting a novel mechanistic link by which H1 and chromatin compaction may mediate pluripotent stem cell differentiation by contributing to the epigenetic silencing of pluripotency genes,” explained Fan. “While a significant reduction in H1 levels does not interfere with embryonic stem cell self-renewal, it appears to impair differentiation.”

The researchers also used a rotary suspension culture method developed by McDevitt to produce with high efficiency homogonous 3D clumps of embryonic stem cells called embryoid bodies. Embryoid bodies typically contain cell types from all three germ layers -- the ectoderm, mesoderm and endoderm -- that give rise to the various types of tissues and structures in the body. However, the majority of the H1 triple-knockout embryoid bodies formed in rotary suspension culture lacked differentiated structures and displayed gene expression signatures characteristic of undifferentiated stem cells.

“H1 triple-knockout embryoid bodies displayed a reduced level of activation of many developmental genes and markers in rotary culture, suggesting that differentiation to all three germ layers was affected.” noted McDevitt.  

The embryoid bodies also lacked the epigentic changes at the pluripotency genes necessary for differentiation, according to Fan.

“When we added one of the deleted H1 subtypes to the embryoid bodies, Oct4 was suppressed normally and embryoid body differentiation continued,” explained Fan. “The epigenetic regulation of Oct4 expression by H1 was also evident in mouse embryos.”

In another experiment, the researchers provided an environment that would encourage embryonic stem cells to differentiate into neural cells. However, the H1 triple-knockout cells were defective in forming neuronal and glial cells and a neural network, which is essential for nervous system development. Only 10 percent of the H1 triple-knockout embryoid bodies formed neurites and they produced on average eight neurites each. In contrast, half of the normal embryoid bodies produced, on average, 18 neurites.

In future work, the researchers plan to investigate whether controlling H1 histone levels can be used to influence the reprogramming of adult cells to obtain induced pluripotent stem cells, which are capable of differentiating into tissues in a way similar to embryonic stem cells.

Research reported in this publication was supported by the National Institute of General Medical Sciences of the National Institutes of Health (NIH) under award number GM085261 and the National Science Foundation under award number CBET-0939511. The content is solely the responsibility of the principal investigators and does not necessarily represent the official views of the NIH or NSF.

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But that could soon change: Researchers at MIT and the Georgia Institute of Technology have developed a way to automate the process of finding and recording information from neurons in the living brain. The researchers have shown that a robotic arm guided by a cell-detecting computer algorithm can identify and record from neurons in the living mouse brain with better accuracy and speed than a human experimenter.

The new automated process eliminates the need for months of training and provides long-sought information about living cells’ activities. Using this technique, scientists could classify the thousands of different types of cells in the brain, map how they connect to each other, and figure out how diseased cells differ from normal cells.

The project is a collaboration between the labs of Ed Boyden, associate professor of biological engineering and brain and cognitive sciences at MIT, and Craig Forest, an assistant professor in the George W. Woodruff School of Mechanical Engineering at Georgia Tech.

“Our team has been interdisciplinary from the beginning, and this has enabled us to bring the principles of precision machine design to bear upon the study of the living brain,” Forest says. His graduate student, Suhasa Kodandaramaiah, spent the past two years as a visiting student at MIT, and is the lead author of the study, which appears in the May 6 issue of Nature Methods.

The method could be particularly useful in studying brain disorders such as schizophrenia, Parkinson’s disease, autism and epilepsy, Boyden says. “In all these cases, a molecular description of a cell that is integrated with [its] electrical and circuit properties … has remained elusive,” says Boyden, who is a member of MIT’s Media Lab and McGovern Institute for Brain Research. “If we could really describe how diseases change molecules in specific cells within the living brain, it might enable better drug targets to be found.”

Automation

Kodandaramaiah, Boyden and Forest set out to automate a 30-year-old technique known as whole-cell patch clamping, which involves bringing a tiny hollow glass pipette in contact with the cell membrane of a neuron, then opening up a small pore in the membrane to record the electrical activity within the cell. This skill usually takes a graduate student or postdoc several months to learn.

Kodandaramaiah spent about four months learning the manual patch-clamp technique, giving him an appreciation for its difficulty. “When I got reasonably good at it, I could sense that even though it is an art form, it can be reduced to a set of stereotyped tasks and decisions that could be executed by a robot,” he says.

To that end, Kodandaramaiah and his colleagues built a robotic arm that lowers a glass pipette into the brain of an anesthetized mouse with micrometer accuracy. As it moves, the pipette monitors a property called electrical impedance — a measure of how difficult it is for electricity to flow out of the pipette. If there are no cells around, electricity flows and impedance is low. When the tip hits a cell, electricity can’t flow as well and impedance goes up.

The pipette takes two-micrometer steps, measuring impedance 10 times per second. Once it detects a cell, it can stop instantly, preventing it from poking through the membrane. “This is something a robot can do that a human can’t,” Boyden says.

Once the pipette finds a cell, it applies suction to form a seal with the cell’s membrane. Then, the electrode can break through the membrane to record the cell’s internal electrical activity. The robotic system can detect cells with 90 percent accuracy, and establish a connection with the detected cells about 40 percent of the time.

The researchers also showed that their method can be used to determine the shape of the cell by injecting a dye; they are now working on extracting a cell’s contents to read its genetic profile.

Development of the new technology was funded primarily by the National Institutes of Health, the National Science Foundation and the MIT Media Lab.

New era for robotics

The researchers recently created a startup company, Neuromatic Devices, to commercialize the device.

The researchers are now working on scaling up the number of electrodes so they can record from multiple neurons at a time, potentially allowing them to determine how different parts of the brain are connected.

They are also working with collaborators to start classifying the thousands of types of neurons found in the brain. This “parts list” for the brain would identify neurons not only by their shape — which is the most common means of classification — but also by their electrical activity and genetic profile.

“If you really want to know what a neuron is, you can look at the shape, and you can look at how it fires. Then, if you pull out the genetic information, you can really know what’s going on,” Forest says. “Now you know everything. That’s the whole picture.”

Boyden says he believes this is just the beginning of using robotics in neuroscience to study living animals. A robot like this could potentially be used to infuse drugs at targeted points in the brain, or to deliver gene therapy vectors. He hopes it will also inspire neuroscientists to pursue other kinds of robotic automation — such as in optogenetics, the use of light to perturb targeted neural circuits and determine the causal role that neurons play in brain functions.

Neuroscience is one of the few areas of biology in which robots have yet to make a big impact, Boyden says. “The genome project was done by humans and a giant set of robots that would do all the genome sequencing. In directed evolution or in synthetic biology, robots do a lot of the molecular biology,” he says. “In other parts of biology, robots are essential.”

Other co-authors include MIT grad student Giovanni Talei Franzesi and MIT postdoc Brian Y. Chow. 

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In the SUMMER 2012 session Margaret Kosal, PhD, (INTA professor) and Robert Butera, PhD, are offering this course in Biotechnology and International Affairs which is cross-listed between BMED and INTA.

NOTE: This is a 5 week session, taught 3 hours/day 3 days/week for 5 weeks. Take note of the dates/days when registering!

INTA 8803 MK / BMED 8813 BIS

Biotechnology and International Security

This course will explore the interface between biotechnology and national security concerns. Rapid biotechnological changes are anticipated to occur over the ensuing decades in a globalized world characterized by complex security challenges. What security concerns are posed by rapid developments in biotechnology? How do governments deal with these concerns? Can regulatory frameworks keep pace with rapid developments in biotechnology? How are these issues handled at an international level? We will consider the role of government and non-governmental organizations in efforts to control these technologies. Finally, we will examine the role of the industry and the open market in shaping policy on these technologies.

During physiological processes, fibronectin fibers are believed to experience mechanical forces that strain the fibers and cause dramatic structural modifications that change their biological activity. While understanding the role of fibronectin strain events in development and disease progression is becoming increasingly important, detecting and interrogating these events is difficult.

In a new study, researchers identified molecular probes capable of selectively attaching to fibronectin fibers under different strain states, enabling the detection and examination of fibronectin strain events in both culture and living tissues.

“The mechano-sensitive molecular probes we identified allow us to dynamically examine the relevance of mechanical strain events within the natural cellular microenvironment and correlate these events with specific alterations in fibronectin associated with the progression of disease,” said Thomas Barker, an assistant professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.

The study was published on April 23, 2012 in the online early edition of the journal Proceedings of the National Academy of Sciences. Barker worked on the study with Georgia Tech graduate student Lizhi Cao and Harry Bermudez, an assistant professor in the University of Massachusetts Amherst Department of Polymer Science and Engineering. The research was supported by the National Institutes of Health.

Researchers have hypothesized that mechanical forces emanating from cells may partially unfold fibronectin and regulate what proteins bind to it. While simulation and tissue culture experiments support this hypothesis, direct evidence that such molecular events occur in living organisms has not yet been presented, according to Barker.

A technique called intramolecular fluorescence resonance energy transfer (FRET) has been used to detect molecular strain events in fibronectin fibers, but the technique has limitations because it cannot be used on living tissues and requires the fibronectin to be chemically labeled.

“The molecular probes we identified can be used to map molecular strain events in native extracellular matrix and living lung tissues,” explained Barker. “The probes can also be used to study the mechanism by which cells control the mechanical forces that alter fibronectin’s conformation, control the exposure of its binding sites and regulate cell signaling.”

The researchers used a controlled fibronectin fiber deposition and extension technique to apply tension to the fibers and stretch them to 2.6 times their original length without significant breakage. Then they used a technique called phage display to identify peptides capable of discriminating fibronectin fibers under relaxed and strained conditions. The molecular probes displaying peptide sequences LNLPHG and RFSAFY showed the greatest binding affinity to fibronectin fibers and the greatest efficiency in discriminating between relaxed and strained fibers.

For proof-of-concept demonstrations, the researchers used the probes to discriminate fibronectin fibers within native extracellular matrix and mouse lung slices. LNLPHG preferentially attached to relaxed fibronectin fibers, whereas RFSAFY bound to strained fibers. The probes never attached to the same fiber, which confirmed their ability to selectively discriminate regions within a fibronectin fiber network.

“This study strongly suggests that fibronectin fibers under strain display markedly different biochemical signatures that can be used for the molecular-level detection of fibronectin fiber strain,” explained Barker. “The data also show the potential for living tissue to be interrogated for mechano-chemical alterations that lead to physiological and pathological progression.”

In the future, the researchers hope to use these fibronectin strain-sensitive probes to target therapeutics to fibronectin fibers based on their mechanical signature.

This work was supported in part by training grants from the National Institutes of Health (NIH) (Award Nos. T32-GM008433 and T32-EB006343). The content is solely the responsibility of the principal investigators and does not necessarily represent the official views of the NIH.

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The award provides up to $3,000 for the selected applicant to travel abroad with preference given to those who will learn new tools or techniques. To be eligible for the award the trainee must have one year remaining in their research and complete their travel by August 31, 2013. For the 2012-2013 award, the applications are due May 11, 2012.

As the Petit Institute’s founding director, Bob passionately served the community for 14 years and successfully led the institute to national and international prominence in the fields of bioengineering & bioscience.

Everyone that knows Bob, knows he loves to travel. His travels have brought him to all corners of the world and it is through his travel that he has served as a great champion of Georgia Tech and the 
biocommunity as a whole.

The Nerem International Travel Award has allowed trainees an opportunity to travel to a wide variety of international universities and research institutes, including the Karolinska Institute, Stockholm, Sweden; RIKEN Brain Science Institute, Japan; the National University of Singapore;  University of Twente, The Netherlands; Queensland University of Technology, Australia; and Consorzio Interuniversitario Lombardo per L’Elaborazione Automatica, Milan, Italy.

Nerem came to Georgia Tech in the winter of 1987 as a professor in the School of Mechanical Engineering and as the Parker H. Petit Distinguished Chair for Engineering in Medicine. He is one of the grandfathers of the booming bio-community that exists on campus today. Prior to coming to Georgia Tech, he was a professor and chairman in the Department of Mechanical Engineering at the University of Houston from 1979 to 1986 and on the faculty at the Ohio State University form 1964 to 1979.

Famelab Astrobiology is a science communication competition intended to encourage up-and-coming new scientists to hone their skills in communicating complex scientific concepts to public audiences.

Nichelle Nichols, known for her portrayal of Lt. Uhura in the original “Star Trek” television series, will host this event, which also will be webcast live and broadcast on NASA TV.

FameLab Astrobiology finalists will have three minutes to explain a science topic of their choice to a public audience – no slides, no charts, and only props they can carry onstage. A panel of experts in science and science communication will judge the competition.

Since January more than 70 early-career astrobiologists have competed in Famelab Astrobiology preliminary competitions in Houston, Denver, Washington, D.C., and online. The 10 finalists, from all over the country, will compete in the Atlanta finals. The winner in Atlanta will compete in International FameLab’s final competition in the U.K. this summer.

The Atlanta finals are the culmination of the first annual Famelab Astrobiology competition, sponsored by NASA’s Astrobiology Program. Famelab Astrobiology, an offshoot of International FameLab, aims to provide experience and training in science communication to the next generation of astrobiologists.

The FameLab Astrobiology competition is being held in conjunction with AbSciCon 2012, an astrobiology science conference with over 750 attendees taking place on the campus of Georgia Tech.  Loren Williams, Ph.D., professor in the School of Chemistry and Biochemistry and Eric Gaucher, Ph.D., associate professor from the School of Biology at Georgia Tech are the co-chairs of the conference.   The AbSciCon conference, held every two years, focuses on the multidisciplinary field of astrobiology – the study of the origin, evolution, distribution, and future of life in the universe – and highlights research supported by NASA's Astrobiology Program.

 

AbSciCon 2012 on Twitter: https://twitter.com/#!/AbSciCon12

AbSciCon 2012 on Facebook : http://www.facebook.com/AbSciCon2012

During her visit in February, Boyan met with several congressmen, urging them to reauthorize “The Pediatric Medical Device Safety and Improvement Act." The law provides grants to fund non-profit pediatric device consortia, such as the Atlanta Pediatric Device Consortium. The grants connect scientists and innovators with device manufacturers, providing them financial resources and regulatory guidance needed to advance the development of devices for children.

“The funding from the FDA has opened many doors and some of our small companies have been able to secure venture capital funding to pursue these devices,” Boyan said.

One of three FDA-sponsored consortia awarded last year, the Atlanta Pediatric Device Consortium is a partnership between Georgia Tech, Children’s Healthcare of Atlanta and Emory University.

The Atlanta Pediatric Consortium provides assistance with engineering design, prototype development, pre-clinical and clinical studies and commercialization for novel pediatric medical devices. It is currently composed of nine projects, three main projects and six pilot projects, which were incorporated from the first Pediatric Device Competition.

“This consortium has brought excitement to the Atlanta Community and strengthened our research partnerships to develop the future of pediatric medical devices,” Boyan said.

Passed in 2007, “The Pediatric Medical Device Safety and Improvement Act" includes important incentives that promote the development of medical devices for children, which currently lags five to 10 years behind those for adults. Significant barriers to pediatric device development exist, including physiological differences in pediatric patients and challenges with recruiting pediatric participants for clinical trial. The law helps to support the creation of more pediatric devices, with 107 device projects developed during the program’s first two years, according to a report by the General Accounting Office.

Boyan was accompanied to D.C. by consortium co-directors Kevin Maher, MD, a cardiologist and researcher specializing in pediatrics with appointments at the Children’s Healthcare of Atlanta Sibley Heart Center and Emory University and Wilbur Lam, MD, PhD, a pediatric hematologist/oncologist and bioengineer with appointments at Emory, the Aflac Cancer Center of Children’s Healthcare of Atlanta and Georgia Tech.

“I wanted to put what I was learning in lecture into practice, and getting involved in research was a way to make this happen,” said Fan, who will receive his bachelor of science in Mechanical Engineering next month.

Fan is one of 165 students who will present at this year’s Undergraduate Research Spring Symposium on April 10 from 1 to 6 p.m. The event is an opportunity for undergraduate students to share their research with students, faculty and staff from across campus.

According to Chris Reaves, director of undergraduate research, about 42 percent of graduating seniors indicate that they had an undergraduate research experience.

Fan began working with Sulchek, an assistant professor in the School of Mechanical Engineering, two years ago. Sulchek’s interest in working with undergraduates stemmed from his own positive experience as a student.

“As an undergraduate, I was able to get involved with research and had a great experience,” Sulchek said. “So it’s important to me to provide students with the same opportunity. I just wish more undergraduates would take advantage of these opportunities while they’re at Tech.”

When Fan began working in Sulchek’s lab, there were some initial challenges. For example, the first project he worked on wasn’t the best fit for him. It was more chemical engineering-based than mechanical, and it was difficult to collaborate with fellow students in the lab because none of them were working on a project similar to Fan’s.

“But I appreciated that Dr. Sulchek let me pursue the project and figure this out for myself,” Fan said.

Before Fan could get frustrated, Sulchek offered him the opportunity to work on another project that was a better fit.

One aspect of Sulchek’s research in nanotechnology is using an atomic force
microscope (AFM). The AFM “sees” tiny objects (such as molecules) with the help of a small probe that touches the object’s surfaces and creates an image based on what it feels.

Unfortunately, the probe or the surface often gets damaged during the process. To remedy the problem, Fan created a method to hover the AFM’s probe at a fixed distance above the surface, which decreases the risk of damage to the probe and the surface.

Last month, Fan’s research was published for the first time in an academic journal, the Review of Scientific Instruments — which doesn’t happen to most undergraduates, Sulchek added.

“It’s so amazing to see more than a year’s work finally pay off, ” said Fan, who will spend the summer working in Sulchek’s lab before he moves on to graduate school.

The two do have a few words of advice for faculty members who work with undergraduate researchers. For example, Sulchek recommends that the faculty member ensure that the student’s project be well defined so that progress can be made in the time the student is working in the lab. He also suggests that a graduate student mentor be assigned to each undergraduate researcher.

Fan suggests that faculty members make time to meet with the students one-on-one, as that was an important part of his success in Sulchek’s lab.

For more about the spring symposium and other undergraduate research opportunities at Tech, click here.

If mimicked by artificial systems, this photocatalytic process could provide abundant new supplies of oxygen and, possibly hydrogen, as a by-product of producing electricity. However, despite its importance to the survival of the planet, scientists don’t fully understand the complex process plants use to harness the sun’s energy.

A paper published April 2 in the journal Proceedings of the National Academy of Sciences moves scientists closer to that understanding by showing the importance of a hydrogen bonding water network in that portion of the photosynthetic machinery known as photosystem II. Using Fourier transform infrared spectroscopy (FT-IR) on photosystem II extracted from ordinary spinach, researchers at the Georgia Institute of Technology tested the idea that a network of hydrogen-bonded water molecules plays a catalytic role in the process that produces oxygen.

“By substituting ammonia, an analog of the water molecule that has a similar structure, we were able to show that the network of hydrogen-bonded water molecules is important to the catalytic process,” said Bridgette Barry, a professor in Georgia Tech’s School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Biosciences. “Substituting ammonia for water inhibited the activity of the photosystem and disrupted the network. The network could be reestablished by addition of a simple sugar, trehalose.”

The research was supported by the National Science Foundation (NSF) and published in the Early Edition of the journal.

In the chloroplasts of green plants, algae and cyanobacteria, oxygen is produced by the accumulation of photo-induced oxidizing equivalents in a structure known as the oxygen-evolving complex (OEC). The OEC contains manganese and calcium ions. Illumination causes oxidation of manganese ions in the OEC. Short laser flashes can be used to step through the reaction cycle, which involves four sequential light-induced oxidation reactions. Oxygen is produced on the fourth step, and then is released from the OEC.  

This so-called S state cycle resets with the binding of the substrate, water. Scientists have proposed that a hydrogen bond network, which includes multiple water molecules bound to manganese ions, calcium ions, and protein amide carbonyl (C=O) groups, forms an electrostatic network surrounding the OEC. In this scenario, the extensive hydrogen-bond network would then serve as a component of the catalyst, which splits off oxygen.

To study the process, Barry and graduate student Brandon Polander used precision FT-IR spectroscopy to describe how the network reacts to a short laser flash. The second harmonic of a pulsed Nd-Yag laser was used as the light source. This illumination causes the OEC to undergo one step in its catalytic cycle, the so-called S₁ to S₂ transition. An infrared spectrum was recorded before and after a laser flash to the photosystem sample, which was isolated from supermarket spinach.

The exquisite sensitivity of FT-IR spectroscopy allowed them to measure changes in the bond strength of the protein C=O groups. The energies of these C=O groups were used as markers of hydrogen bond strength. The brief laser flash oxidized a manganese ion and caused a change in the strength of the C=O bond, which reported an increase in hydrogen bonding to water molecules. When ammonia was added as an inhibitor, a decrease in C=O hydrogen bonding was observed instead. Addition of trehalose, which is known to change the ordering of water molecules at the surface of proteins, blocked this effect of ammonia.   

The study describes the coordinated changes that must occur in the protein to facilitate the reaction and shows that the strength of the hydrogen-bonded network is important. 

“This research helps to clarify how ammonia inhibits the photosystem, which is something that researchers have been wondering about for many years,” Barry explained. “Our work suggests that ammonia can inhibit the reaction by disrupting this network of hydrogen bonds.” 

The research also suggests that in design of artificial devices that carry out this reaction, sustaining a similar hydrogen-bonding network may be important. The stabilizing effect of trehalose discovered by Polander and Barry may also be important.

Beyond the importance of understanding the photosynthetic process, the work could lead to new techniques for producing hydrogen and oxygen using sunlight. One possibility would be to add a biomimetic photocatalytic process to a photovoltaic system producing electricity from the sun.

 “In terms of providing new sources of energy, we still have lessons to learn from plants about how they carry out these critical processes,” Barry said. “It would be a great advance for the planet to have new, sustainable, and inexpensive processes to carry out this reaction.”

Ultimately, she hopes the full water oxidizing cycle can be explored and potentially harnessed or imitated for oxygen and energy production.

“We are only looking at a single part of the overall reaction now, but we would like to study the entire cycle, in which oxygen is produced, to see how the interactions in the water network change and how the interactions with the protein change,” Barry said. “The work is another step in understanding how plants carry out this amazing series of photosynthetic reactions.”

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Thanks to a grant from the National Science Foundation, Gilda Barabino, professor of biomedical engineering at Georgia Tech, organized the workshop to bring together distinguished, talented and innovative engineering professionals to address this challenge, which is related to enhanced global competiveness and an improved national economy.

The workshop attracted more than 70 engineering faculty and innovators from Harvard, Stanford, North Carolina A &T State University and other leading institutions. Researchers who attended gained insight, resources and knowledge toward activities that support innovation, entrepreneurial endeavors and ultimately, the economic status of our nation, Barabino said.

As an internationally recognized researcher and educator and the newly elected president of the Biomedical Engineering Society, Barabino has committed herself to her technical career and to impacting the future by developing opportunities for innovation and career success among minority faculty.

“By providing opportunities for professional development linked to a better understanding of research innovation and translation, the [workshop] contributes to the development and retention of a well equipped faculty cadre,” Barabino said. “It broadens the talent pool for translational research that drives company formation, job creation, a healthy economy and global competitiveness.”

Georgia Tech Dean of Engineering Gary May, who was one of the conference sponsors, said the workshop is a positive step toward increasing underrepresented faculty in the STEM fields.

“Faculty are the intellectual life blood of universities, so faculty development is a critical issue,” May said. “This is particularly true for underrepresented faculty in STEM fields, as there are too few of us to allow any to be unsuccessful. I applaud the Minority Faculty Development Workshop for seeking solutions which will contribute to successful, enriched, and fulfilling careers for its participants.”

National Science Foundation Program Director Omnia El-Hakim stressed the importance of attracting more women to engineering.

“Women constitute 50 percent of the U.S. Population, but are not represented fully in the engineering disciplines nor in entrepreneurship,” El-Hakim said. “The NSF believes in broadening participation through these types of programs because diversification in these realms brings important perspectives in solving challenges of national concern while maintaining excellence.”

The NSF Minority Faculty Development Workshop: Engineering Enterprise and Innovation was the sixth in a series that began in 2001 with funding under the NSF Engineering Directorate. The workshop addressed strategic goals of the National Science Foundation and critical needs of the nation related to enhanced global competiveness and an improved national economy.

To address this challenge, researchers from the Georgia Institute of Technology and Emory University have designed a new treatment approach that appears to halt the spread of cancer cells into normal brain tissue in animal models. The researchers treated animals possessing an invasive tumor with a vesicle carrying a molecule called imipramine blue, followed by conventional doxorubicin chemotherapy. The tumors ceased their invasion of healthy tissue and the animals survived longer than animals treated with chemotherapy alone.

“Our results show that imipramine blue stops tumor invasion into healthy tissue and enhances the efficacy of chemotherapy, which suggests that chemotherapy may be more effective when the target is stationary,” said Ravi Bellamkonda, a professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. “These results reveal a new strategy for treating brain cancer that could improve clinical outcomes.”

The results of this work were published on March 28, 2012 in the journal Science Translational Medicine. The research was supported primarily by the Ian’s Friends Foundation and partially by the Georgia Cancer Coalition, the Wallace H. Coulter Foundation and a National Science Foundation graduate research fellowship.

In addition to Bellamkonda, collaborators on the project include Jack Arbiser, a professor in the Emory University Department of Dermatology; Daniel Brat, a professor in the Emory University Department of Pathology and Laboratory Medicine; and the paper’s lead author, Jennifer Munson, a former Fulbright Scholar who was a bioengineering graduate student in the Georgia Tech School of Chemical & Biomolecular Engineering when the research was conducted.

Arbiser designed the novel imipramine blue compound, which is an organic triphenylmethane dye. After in vitro experiments showed that imipramine blue effectively inhibited movement of several cancer cell lines, the researchers tested the compound in an animal model of aggressive cancer that exhibited attributes similar to a human brain tumor called glioblastoma.

“There were many reasons why we chose to use the RT2 astrocytoma rat model for these experiments,” said Brat. “The tumor exhibited properties of aggressive growth, invasiveness, angiogenesis and necrosis that are similar to human glioblastoma; the model utilized an intact immune system, which is seen in the human disease; and the model enabled increased visualization by MRI because it was a rat model, rather than a mouse.”

Because imipramine blue is hydrophobic and doxorubicin is cytotoxic, the researchers encapsulated each compound in an artificially-prepared vesicle called a liposome so that the drugs would reach the brain. The liposomal drug delivery vehicle also ensured that the drugs would not be released into tissue until they passed through leaky blood vessel walls, which are only present where a tumor is growing.

Animals received one of the following four treatments: liposomes filled with saline, liposomes filled with imipramine blue, liposomes filled with doxorubicin chemotherapy, or liposomes filled with imipramine blue followed by liposomes filled with doxorubicin chemotherapy.

All of the animals that received the sequential treatment of imipramine blue followed by doxorubicin chemotherapy survived for 200 days -- more than 6 months -- with no observable tumor mass. Of the animals treated with doxorubicin chemotherapy alone, 33 percent were alive after 200 days with a median survival time of 44 days. Animals that received capsules filled with saline or imipramine blue – but no chemotherapy -- did not survive more than 19 days.

“Our results show that the increased effectiveness of the chemotherapy treatment is not because of a synergistic toxicity between imipramine blue and doxorubicin. Imipramine blue is not making the doxorubicin more toxic, it’s simply stopping the movement of the cancer cells and containing the cancer so that the chemotherapy can do a better job,” explained Bellamkonda, who is also the Carol Ann and David D. Flanagan Chair in Biomedical Engineering and a Georgia Cancer Coalition Distinguished Cancer Scholar.

MRI results showed a reduction and compaction of the tumor in animals treated with imipramine blue followed by doxorubicin chemotherapy, while animals treated with chemotherapy alone presented with abnormal tissue and glioma cells. MRI also indicated that the blood-brain barrier breach often seen during tumor growth was present in the animals treated with chemotherapy alone, but not the group treated with chemotherapy and imipramine blue.

According to the researchers, imipramine blue appears to improve the outcome of brain cancer treatment by altering the regulation of actin, a protein found in all eukaryotic cells. Actin mediates a variety of essential biological functions, including the production of reactive oxygen species. Most cancer cells exhibit overproduction of reactive oxygen species, which are thought to stimulate cancer cells to invade healthy tissue. The dye’s reorganization of the actin cytoskeleton is thought to inhibit production of enzymes that produce reactive oxygen species.

“I formulated the imipramine blue compound as a triphenylmethane dye because I knew that another triphenylmethane dye, gentian violet, exhibited anti-cancer properties, and I decided to use imipramine -- a drug used to treat depression -- as the starting material because I knew it could get into the brain,” said Arbiser.

For future studies, the researchers are planning to test imipramine blue’s effect on animal models with invasive brain tumors, metastatic tumors, and other types of cancer such as prostate and breast.

“While we need to conduct future studies to determine if the effect of imipramine blue is the same for different types of cancer diagnosed at different stages, this initial study shows the possibility that imipramine blue may be useful as soon as any tumor is diagnosed, before anti-cancer treatment begins, to create a more treatable tumor and enhance clinical outcome,” noted Bellamkonda. 

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Team MAID is composed of seniors Alex Cooper, Elizabeth Flanagan, Shawna Hagen and Jacob Thompson.  Their plan and presentation won first place in the Undergraduate Competition, 1st Place in the Overall Competition, Most Commercializable Plan and the Alumni Award in the poster session for total winnings of $42,500.

Their win represents the first time a team of undergraduates has won the overall competition, which draws undergraduate and graduate students from across Georgia Tech. The Business Plan Competition is organized annually by Georgia Tech’s College of Management.

MAID is a simplified approach to intubation that utilizes magnets to guide the endotracheal tube into the airway of a patient easily and quickly, with less risk and without the need for visualization. MAID has two components: the single-use magnetic stylet and the reusable guide magnet. The external guide magnet is placed above the cricoid cartilage of the patient. When the endotracheal tube with the magnetic stylet is inserted into the patient’s mouth, it is pulled directly into the airway by the guide magnet, resulting in near effortless intubation.

Last year the team MAID also won second place in Georgia Tech’s InVenture Prize competition, winning $10,000 cash and a patent application by the Office of Technology Licensing. In summer 2011, the Translational Research Institute for Biomedical Engineering & Science awarded the team a seed grant of $25,000 to for further prototype development of the device.

The Saint Joseph Translation Research Institute has tested their functioning prototype on multiple human cadavers with considerable success. The Office of Technology Licensing filed a full non-provisional patent in March 2012. Currently, additional design work is being conducted to improve manufacturability and reliability. The MAID design concept to improve the safety and effectiveness of the intubation procedure began as a team design project in BMED 2300, Projects in Biomedical Engineering. Franklin Bost, Professor of the Practice in biomedical engineering, and Leanne West at the Georgia Tech Research Institute, continue to advise the MAID team.

Kevin Lewis, another biomedical engineering student, whose plan for “Cold Crate” came in third in the Undergraduate Track of the Business Plan competition. Graduate student Melissa Li was a finalist for her team’s CARDIAM device and the winner of a $10,000 services package for Most Innovative Technology.  The CARDIAM Team was also a co-winner in the Elevator Pitch Competition.

Written by Adrianne Proeller, Wallace H. Coulter Dept. of Biomedical Engineering.

Best BioE Ph.D. Thesis
Edward Phelps, Ph.D. - Garcia Lab -  Award Recipient 2012

Best BioE Advisor
Dr. Melissa Kemp, BMED - Award Recipient 2012

To honor these recipients, an awards ceremony will be held Fall semester 2012.

The Institute’s College of Engineering ranked No. 4 for theeighth consecutive year and all eleven of the programs within the college areranked in the top 10 including industrial engineering (No. 1), biomedical and bioengineering (No.2), civil (No. 3), aerospace (No. 4), electrical (No. 5), nuclear (No. 5), environmental(No. 6), computer (No. 6), mechanical (No. 6), materials (No. 7) and chemical(No. 10).

“All of Georgia Tech’s graduateengineering programs are ranked in the top ten in the nation.  We’re proud that our College of Engineeringis not only one of the best in the U.S., but also the largest, preparing nearly3,000 graduates each year,” said Georgia Tech President G. P. “Bud”Peterson.  “We commend our outstandingfaculty, staff and students who helped make this a reality.”

Georgia Tech appears on the top 10 list of engineering specialties more than any other ranked institution.

The Georgia Tech College of Management full-time MBA programranked No. 32, while the Institute’s part-time MBA program ranked No. 28.

Xia is the Brock Family Chair and GRA Eminent Scholar in Nanomedicine in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, with a joint appointment in the School of Chemistry and Biochemistry. His research focuses on nanocrystals -- a novel class of materials with features smaller than 100 nm -- as well as the development of innovative technologies enabled by nanocrystals. These technologies span the fields of molecular imaging, early cancer diagnosis, targeted drug delivery, biomaterials, regenerative medicine and catalysis.

“The possible applications of nanotechnology in medicine have only begun to be explored, said Michael Cassidy, President and CEO of the Georgia Research Alliance. “Dr. Xia’s expertise and collaborative vision will lead to vital new scientific discoveries that can be transformed into new tools to help people live healthier lives.”

Xia received his Ph.D. in physical chemistry from Harvard University in 1996, his M.S. in inorganic chemistry from University of Pennsylvania (with the late Professor Alan G. MacDiarmid, a Nobel Laureate in Chemistry, 2000) in 1993. He has received a number of prestigious awards, including AIMBE Fellow (2011), MRS Fellow (2009), NIH Director's Pioneer Award (2006), Leo Hendrik Baekeland Award (2005), Camille Dreyfus Teacher Scholar (2002), David and Lucile Packard Fellowship in Science and Engineering (2000), Alfred P. Sloan Research Fellow (2000), NSF Early Career Development Award (2000) and the ACS Victor K. LaMer Award (1999).

“Dr. Xia is a world-renowned teacher and leader at the forefront of nanomedicine and materials science,” said Larry McIntire, the Wallace H. Coulter Chair of Biomedical Engineering. “His reputation and innovative research in these areas will clearly strengthen our expanding efforts in nanomedicine and biomaterials. We are honored to welcome him to the department and to the Institute.”

Ongoing research at Georgia Tech aims to answer this question in an experimental approach by adding rigor to the methods and protocols used to resurrect components of ancient life.

Dr. Eric Gaucher, Associate Professor in the School of Biology, was recently awarded $700K from the National Science Foundation (NSF) to, for the first time, benchmark ancestral sequence reconstruction methods. Prof. Gaucher’s approach involves generating a known experimental phylogeny in the lab using fluorescent proteins cloned into bacteria. Generating such a “known” phylogeny with evolved sequences will, in turn, allow the group to test resurrection predictions since the true ancestral proteins are generated in the laboratory and are thus known.

An important component of the funding involves integrating evolutionary and molecular biology research into the greater Atlanta community. In collaboration with Dunwoody High school, Dr. Gaucher and Ryan Randall have developed a new Biotechnology curriculum whereby students are introduced to the connections between genotype and phenotype by evolving fluorescent proteins at the high school. In addition, The Gaucher Group annually hosts a team of Dekalb county high school students competing in the National Siemens Competition in Math, Science and Technology, that involves bioengineering of fluorescent proteins.

For his efforts, Prof. Gaucher is also a recent recipient of Georgia Tech’s Class of 1934 Teaching Award. This award is based on student evaluations and presented to faculty with the highest ratings in overall effectiveness in teaching.

There is only one downside. Those sequencing technologiesprovide massive amounts of data that are not easily processed and translated byscientists. That’s why Georgia Tech has created a new data analysis algorithmthat quickly transforms complex RNA sequence data into usable content forbiologists and clinicians. The RNA-Seq analysis pipeline (R-SAP) was developedby School of Biology Professor John McDonald and Ph.D. Bioinformatics candidateVinay Mittal. Details of the pipeline are published in the journal NucleicAcids Research.

“A major bottleneck in the realization of the dream ofpersonalized medicine is no longer technological. It’s computational,” saidMcDonald, director of Georgia Tech’s newly created Integrated Cancer ResearchCenter. “R-SAP follows a hierarchical decision-making procedure to accurately characterizevarious classes of gene transcripts in cancer samples.”

There are at least 23,000 pieces of RNA in the humangenome that encode the sequence of proteins. Millions of other pieces helpregulate the production of proteins. R-SAP is able to quickly determine everygene’s level of RNA expression and provide information about splice variants,biomarkers and chimeric RNAs. Biologists and clinicians will be able to morereadily use this data to compare the RNA profiles or “transcriptomes” of normalcells with those of individual cancers and thereby be in a better position todevelop optimized personal therapies.

Personalized approaches to cancer medicine are already inwidespread use for a few “cancer biomarkers” including variants of the BRAC 1gene that can be used to identify women with a high risk of developing breastand ovarian cancer.

“Our goal was to design a pipeline that is easilyinstallable with parallel processing capabilities,” said Mittal. “R-SAP canmake 100 million reads in just 90 minutes. Running the program simultaneouslyon multiple CPUs can further decrease that time.”

R-SAP is open source software, freely accessible at theMcDonald Lab website.

“This is another example of Georgia Tech’s ability tomerge computer technology with science to create an essential feature ofnext-generation bioinformatics tools,” said McDonald. “We hope that R-SAP willbe a useful and user-friendly instrument for scientists and clinicians in thefield of cancer biology.”

Georgia Tech researchers are developing new ways to diagnose and treat heart problems -- from advanced imaging techniques and guidance for drug therapies to sophisticated surgical procedures. Georgia Tech’s emphasis on translational research accelerates the pace at which new heart-related discoveries are put to use in patient care.

Improving Heart Surgery

To advance the goal of minimally invasive cardiac surgery, researchers have developed a technology that simplifies and standardizes the technique for opening and closing the beating heart during surgery.

Apica Cardiovascular, a Georgia Tech and Emory University medical device startup, licensed the technology from the two institutions. The firm recently received a $5.5 million investment to further develop the system, which will make the transapical access and closure procedure required for delivering therapeutic devices to the heart more routine for cardiac surgeons. The goal is to expand the use of surgery techniques that are less invasive and do not require stopping the heart.

With research and development support from the Coulter Foundation Translational Research Program and the Georgia Research Alliance, the company has already completed a series of pre-clinical studies to test the functionality of the device and its biocompatibility. James Greene currently serves as the CEO of the company, which has offices in Galway, Ireland, and in Atlanta.

For more information on this work, visit http://gtresearchnews.gatech.edu/apica-cardiovascular/.

Diagnosing Heart Disease

Levent Degertekin is designing tiny devices micromachined from silicon that may make diagnosing and treating coronary artery diseases easier.

Degertekin, the George W. Woodruff Chair in Mechanical Systems, and Paul Hasler, a professor in the School of Electrical and Computer Engineering at Georgia Tech, micromachined intravascular ultrasound imaging arrays with integrated electronics. Placed on catheters inserted into the body, the devices image the arteries of the heart in three dimensions at high resolution using high-frequency ultrasound waves.

The system boasts a more compact design and three-dimensional imaging capability for guiding cardiologists during interventions, such as those for completely blocked arteries. The technology also offers higher resolution than current intravascular ultrasound systems, which help diagnose vulnerable plaque, a leading cause of heart attacks.

Funding for this research currently is provided by the National Institutes of Health. To commercialize the technology, the researchers have formed a startup company called SIBUS Medical, which is receiving assistance from VentureLab, a unit of Georgia Tech’s Enterprise Innovation Institute that nurtures faculty startup companies.

Detecting and Treating Atherosclerosis

With a five-year $14.6 million contract from the National Institutes of Health (NIH), Georgia Tech and Emory University researchers are developing nanotechnology and biomolecular engineering tools and methodologies for detecting and treating atherosclerosis. The award supports the interdisciplinary Center for Translational Cardiovascular Nanomedicine, which is led by Gang Bao, the Robert A. Milton Chair in Biomedical Engineering in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.

Atherosclerosis typically occurs in branched or curved regions of arteries where plaques form because of cholesterol build-up. Inflammation can alter the structure of plaques so they become more likely to rupture, potentially causing a blood vessel blockage and leading to heart attack or stroke.

The researchers are working to accomplish four goals:

• Using nanoparticle probes to image and characterize atherosclerotic plaques
• Diagnosing cardiovascular disease from a blood sample
• Designing new methods for delivering anti-atherosclerosis drugs and genes into the body
• Developing stem cell based therapies to repair damaged heart tissue

Additional researchers from the Coulter Department and from Emory University are also contributing to the project. For more information on this work, visit http://gtresearchnews.gatech.edu/cardiovascular-nanomedicine-center/.

Improving Drug Dosing Following a Heart Attack

A research team led by Georgia Tech mechanical engineering assistant professor Craig Forest is designing a device to quickly and accurately personalize a patient’s drug dosage to prevent blood clots that can cause heart attacks.

When someone experiencing heart attack symptoms arrives at an emergency room, he or she typically receives a standard dose of aspirin and/or clopidogrel to prevent further blood clotting. But that standard dose may not be the best dose for a given individual.

With Forest’s device, a small blood sample is sent through a microchip containing a network of microfabricated capillaries that mimic the branching coronary arteries around the human heart. Because the branches contain flow restrictions of different sizes, the failure of blood to flow through the branches with smaller restrictions indicates that a higher drug dose may be required.

Determining the necessary dose of anti-clotting drugs can be difficult. Too much of the drug may cause the patient to experience gastrointestinal bleeding. Too little drug may allow additional clot formation and set the stage for another heart attack. Forest’s device should help determine the right dosage for each patient.

Emory University Department of Emergency Medicine assistant professor Jeremy Ackerman and Georgia Tech Regents’ professor of mechanical engineering David Ku are working with Forest on this project, which is supported by the American Heart Association.

Examining Heart Valve Leakage

An estimated 1.6 million Americans suffer moderate to severe leakage through their tricuspid valve, a complex structure that closes off the heart’s right ventricle from the right atrium. If left untreated, severe leakage can affect an individual’s quality of life and can even lead to death.

Research teams led by Ajit Yoganathan, Georgia Tech Regents’ professor and Wallace H. Coulter Distinguished Faculty Chair in Biomedical Engineering, have discovered causes for the tricuspid valve’s leakage and ways to predict the severity of leakage in the valve. These study results could lead to improved diagnosis and treatment of the condition.

A study published in the journal Circulation found that either dilating the tricuspid valve opening or displacing the papillary muscles that control its operation can cause the valve to leak. A combination of the two actions can increase the severity of the leakage, which is called tricuspid regurgitation.

Standard clinical procedures that detail when and how tricuspid valve repairs should be performed need to be developed and this study suggests several items that should be considered in developing those protocols, according to the researchers.

In another study published in the journal Circulation: Cardiovascular Imaging, researchers found that the anatomy of the heart’s tricuspid valve can be used to predict the severity of leakage in the valve. Using 3-D echocardiograms from 64 individuals who exhibited assorted grades of tricuspid leakage, the researchers found that pulmonary arterial pressure, the size of the valve opening and papillary muscle position measurements could be used to predict the severity of an individual’s tricuspid regurgitation.

The study will change the focus and direction of future surgical therapies for tricuspid regurgitation to make them better and more durable, the researchers said.

Researchers from the Coulter Department, Emory University, Children’s Hospital Boston and Mount Sinai Medical Center contributed to these two studies.

For more information on this work, visit http://gtresearchnews.gatech.edu/tricuspid-valve-leakage/ and http://gtresearchnews.gatech.edu/tricuspid-regurgitation/. 

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Writer: Abby Robinson

“Shape-memory alloys exhibit unique characteristics that youwould want for earthquake-resistant building and bridge design and retrofitapplications: they have the ability to dissipate significant energy withoutsignificant degradation or permanent deformation,” said Reginald DesRoches, a professorin the School of Civil and Environmental Engineering at Georgia Tech.

Georgia Tech researchers have developed a model thatcombines thermodynamics and mechanical equations to assess what happens whenshape-memory alloys are subjected to loading from strong motion. The researchersare using the model to analyze how shape-memory alloys in a variety ofcomponents -- cables, bars, plates and helical springs -- respond to different loadingconditions. From that information, they can determine the optimalcharacteristics of the material for earthquake applications.

The model was developed by DesRoches, School of MechanicalEngineering graduate student Reza Mirzaeifar, School of Civil and EnvironmentalEngineering associate professor Arash Yavari, and School of Mechanical Engineeringand School of Materials Science and Engineering professor Ken Gall.

A paper describing the thermo-mechanical model was publishedonline Feb. 3 in the InternationalJournal of Non-Linear Mechanics. This research was supported by theTransportation Research Board IDEA program.

To improve the performance of structures during earthquakes,researchers around the world have been investigating the use of “smart”materials, such as shape-memory alloys, which can bounce back afterexperiencing large loads. The most common shape-memory alloys are made of metalmixtures containing copper-zinc-aluminum-nickel, copper-aluminum-nickel ornickel-titanium. Potential applications of shape-memory alloys in bridge andbuilding structures include their use in bearings, columns and beams, orconnecting elements between beams and columns. But before this class ofmaterials can be used, the effect of extreme and repetitive loads on thesematerials must be thoroughly examined.

“For standard civil engineering materials, you can usemechanics to look at force and displacement to measure stress and strain, butfor this class of shape-memory alloys that changes properties when it undergoesloading and unloading, you have to consider thermodynamics and mechanics,” explainedYavari.

The Georgia Tech team found that the generation andabsorption of heat during loading and unloading caused a temperature gradientin shape-memory alloys, which caused a non-uniform stress distribution in thematerial even when the strain was uniform.

“Shape-memory alloys previously examined in detail werereally thin wires, which can exchange heat with the ambient environment rapidlyand no temperature change is seen,” said Mirzaeifar. “When you start to examinealloys in components large enough to be used in civil engineering applications,the internal temperature is no longer uniform and needs to be taken intoaccount.”

To predict the internal temperature distribution ofshape-memory alloys under loading-unloading cycles, which could then be used todetermine the stress distribution, the researchers developed a model that usedthe surface thermal boundary conditions, diameter and loading rate of the alloyas inputs.

The team included ambient conditions in the model becauseshape-memory alloys for seismic applications could operate in a variety ofenvironments -- such as water if used in bridge structures or air if used inbuilding structures -- which would produce different rates of heat transfer. Theresearchers used a thermal camera to record the variation in surfacetemperature of shape-memory alloys experiencing loading and unloading.

Using their model, the researchers were able to accuratelypredict internal temperature and stress distributions for shape-memory alloys. Themodel results were verified with experimental tests. In one test, they foundthat a shape-memory alloy loaded at a very slow rate had time to exchange theheat created with the ambient environment and exhibited uniform stress. If it wasloaded very rapidly, it did not have enough time to exchange the heat, leadingto a non-uniform stress distribution.

“Our analytical solutions are exact, fast and capable of simulatingthe complicated coupled thermo-mechanical response of shape-memory alloysconsidering temperature changes and loading rate dependency,” said Mirzaeifar.

In future work, the researchers plan to examine morecomplicated shapes and the effects of combination loading -- tension, bendingand torsion -- to optimize shape-memory alloys for earthquake applications.

This project issupported by the Transportation Research Board of the National Academies (AwardNo. NCHRP-147). The National Academies has rights to the data and the contentis solely the responsibility of the principal investigators and does notnecessarily represent the official views of the National Academies.

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Additionally, the new BBUGS website has incorporated a message board whereby BBUGS members can post announcements pertaining to job openings, scholarship/grant availabilities, seminars/workshops or upcoming social activities. The new website design includes new and improved functionality to make navigation throughout the website less complicated and more manageable.

BBUGS is currently the largest, most diverse, graduate student group on the Georgia Tech campus and is an interdisciplinary student group, comprised of 8 different departments, with their home in the Parker H. Petit Institute for Bioengineering and Bioscience. Comprised of over 500 members, BBUGS serves as the core student group for the bioengineering and bioscience community and is open to all Georgia Tech and Emory University students from bio-related fields.  Existing members are encouraged to go to the new website and create a profile to stay engaged. 

"Our research team seeks to understand how certain molecules in a complex mixture can work together to form highly ordered assemblies that exhibit chemical properties similar to those associated with biological molecules," said Nicholas V. Hud, a professor in the Georgia Tech School of Chemistry and Biochemistry. "Such a process was likely an essential and early stage of life, so we are also working to understand what chemicals were present on the prebiotic Earth and what processes helped these chemicals form the complex substances ultimately needed for life."

Hud will direct the effort, which is known as the Center for Chemical Evolution. The five-year grant will support research in more than 15 laboratories at institutions including Georgia Tech, Emory University, the Scripps Research Institute, the Scripps Institution of Oceanography, Jackson State University, Spelman College, Furman University and the SETI Institute.

All of the researchers will work together to accomplish the Center for Chemical Evolution’s three main research goals:

* To identify potential biological building blocks among the products of model prebiotic reactions,
* To investigate the chemical components and conditions that promote the spontaneous assembly of increasingly complex multi-component structures, and
* To prepare and characterize highly-ordered chemical assemblies, and to study their potential to function like biological substances.

"We will work backward from the complex substances found in living organisms today, such as proteins and DNA, and make materials that are a little bit different and simpler in chemical structure," explained Hud. "We will then strive to determine if there were possibly chemicals and conditions on the early Earth that would have given rise to these and similar substances."

In addition, the researchers will translate technological developments into commercially viable products. Facundo Fernandez, an associate professor in the Georgia Tech School of Chemistry and Biochemistry, is leading the Center's commercialization efforts.

For the first research theme, which is being led by Georgia Tech chemistry professor Thomas Orlando, creating a model inventory of the chemicals present on the early Earth will require the development of new tools and approaches for analyzing and sorting complex mixtures.

"Complex mixtures are found in many chemical industries - including petroleum, food and pharmaceuticals," said Fernandez. "The instruments and protocols we develop to sort through the complex mixtures that result from model prebiotic chemical reactions are going to be valuable to these industries too."

Charles Liotta, a Regents professor in the Georgia Tech School of Chemistry and Biochemistry, is leading the second research theme, which involves exploring alternative media that could have facilitated the assembly of complex substances in the prebiotic world. This research could produce environmentally-friendly procedures leading to new chemical processes, according to the team.

In the third research theme, led by David Lynn, chair of the Department of Chemistry at Emory University, and Ram Krishnamurthy, an associate professor of chemistry at the Scripps Research Institute, methods will be developed to create polymers and assemblies that mimic natural macromolecules, such as DNA and proteins. The resulting methods could be used as a platform to create a range of substances with broad commercial applications across the spectrum of therapeutics, diagnostics and drug delivery materials. Lynn will also lead the Center's education and public outreach programs.

The research efforts of the Center will build on the knowledge and results gained during the past three years, during which time a smaller group of laboratories were funded by the National Science Foundation to conduct collaborative research projects and to develop a larger center.

Research progress made during the initial phase of funding includes a paper published June 14 in the journal ChemBioChem. Center laboratories showed for the first time that guanine, a component of DNA, could be produced from formamide (H2NCOH), a simple chemical known to exist in outer space.

Previous research had shown that the other three building blocks of nucleic acids - cytosine, adenine and uracil - could be synthesized by heating formamide in the presence of mineral catalysts, but not guanine.

Center researchers produced guanine from formamide by subjecting the sample to ultraviolet light during the heating process. The results also demonstrated that guanine, adenine and another building block called hypoxanthine could be produced at lower temperatures than previously reported.

"Our ultimate goal is to create a complete chemical pathway showing how relatively simple substances can interact with the environment and each other to spontaneously produce complex assemblies that exhibit properties normally associated with biological substances, and perhaps shed some light on the earliest stages of life on Earth," noted Hud.

Thescientists showed for the first time how the virus called “Lambda” evolved tofind a new way to attack host cells, an innovation that took four mutations toaccomplish. This virus infects bacteria, in particular the common E. coli bacterium. Lambda isn’tdangerous to humans, but this research demonstrated how viruses evolve complexand potentially deadly new traits, said Justin Meyer, MSU graduate student, whoco-authored the paper with Richard Lenski, MSU Hannah Distinguished Professorof Microbiology and Molecular Genetics.

“Wewere surprised at first to see Lambda evolve this new function, this ability toattack and enter the cell through a new receptor­ – and it happened so fast,”Meyer said. “But when we re-ran the evolution experiment, we saw the same thinghappen over and over.”

Thispaper comes on the heels of news that scientists in the U.S. and theNetherlands produced a deadly version of bird flu. Even though bird flu is amere five mutations away from becoming transmissible between humans, it’shighly unlikely the virus could naturally obtain all of the beneficialmutations all at once. However, it might evolve sequentially, gaining benefitsone-by-one, if conditions are favorable at each step, he added.

Throughresearch conducted at BEACON, MSU’s National Science Foundation Center for theStudy of Evolution in Action, Meyer and his colleagues’ ability to duplicatethe results implied that adaptation by natural selection, or survival of thefittest, had an important role in the virus’ evolution.

Whenthe genomes of the adaptable virus were sequenced, they always had fourmutations in common.

“Theparallelism shown in the evolutionary history of adaptable viruses was strikingand was far beyond what is expected by chance,” noted paper co-author Joshua Weitz, anassistant professor in the School ofBiology at Georgia Tech.

Incontrast, the viruses that didn’t evolve the new way of entering cells had someof the four mutations but never all four together, said Meyer, who holds theBarnett Rosenberg Fellowship in MSU’s College of Natural Science.

“Inother words, natural selection promoted the virus’ evolution because themutations helped them use both their old and new attacks,” Meyer said. “Thefinding raises questions of whether the five bird flu mutations may also havemultiple functions, and could they evolve naturally?”

Additionalauthors of the paper include Devin Dobias, former MSU undergraduate (now agraduate student at Washington University in St. Louis); Ryan Quick, MSUundergraduate; and Jeff Barrick, a former Lenski lab researcher now on thefaculty at the University of Texas at Austin.

Fundingfor the research was provided in part by the National Science Foundation,Defense Advanced Research Projects Agency, James S. McDonnell Foundation andBurroughs Wellcome Fund.

This research was supported in part bythe Defense Advanced Research Projects Agency (DARPA) (Award No.HR0011-09-1-0055) and the National Science Foundation (NSF). The content issolely the responsibility of the principal investigator and does notnecessarily represent the official views of DARPA or NSF.

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Writer: Layne Cameron

“Given that breast cancer is the most common cancer in U.S. women and the second leading cause of cancer death, many people could benefit from the development of effector nanoclusters,” Champion says. “This work validates the idea of using bacterial proteins for therapeutic applications and the concept can be expanded for a variety of drug development and delivery needs for other diseases.”

A select group of bacterial pathogens secrete proteins called effectors during infection, which enable them to survive and grow in a hostile host. Some of these effectors have the capability to interfere with the same pathways that are altered in breast cancer.

“The goal of my research is to use these effector proteins as novel breast cancer therapies,” Champion says. “In order for these proteins to be used as anticancer drugs, the normal bacterial delivery mechanisms must be replaced by a drug delivery system able to deliver biologically active protein to breast cancer cells.” 

To engineer this modified drug delivery system, the effector proteins must be linked together into nano-sized clusters that can enter breast cancer cells and then fall apart to allow the individual proteins to act inside the cells. By fabricating effector nanoclusters, Champion will be able to access their ability to restore normal behaviors in breast cancer cells, such as increased apoptotic cell death, decreased proliferation, decreased metastasis, and increased sensitivity to chemotherapeutics.

After receiving her PhD from the University of California, Santa Barbara in 2007, Champion completed a postdoctoral appointment as a National Institutes of Health Postdoctoral Fellow at the California Institute of Technology. She joined the faculty at Georgia Tech in 2009, where she focuses her research on protein engineering strategies to synthesize novel materials capable of specific interactions with cells or other proteins. The overall goal of her research is to reverse disease through interference with inflammatory pathways or promotion of healing mechanisms.

This project was supported by the National Science Foundation (NSF) (Award No. DMR-1105248). The content is solely the responsibility of the principal investigators and does not necessarily represent the official views of the NSF.

Cross was invitedto present testimony at the hearing entitled, “Doing Business with the DOD:Getting Innovative Solutions from Concept to the Hands of the Warfighter.” Thepanel asked for insight on the role that universities, research institutionsand laboratories play in developing innovative technologies for the Departmentof Defense, particularly in the effort to transition research from academicconcept into production.

As part ofhis testimony, Cross highlighted Georgia Tech’s FY 2011 $643 million in researchexpenditures and how the institute supports and translates defense researchthrough technology transition and innovation programs.

“Defenseresearch and associated technology transition and innovation programs are vitalfor ensuring the United States retains a competitive advantage in its nationalsecurity posture,” Cross said. “As shown time and time again, the fruits ofdefense research seed economic development helping accelerate new technologies tomarket.”

According toCross, such technologies are available for use in defense systems at a fractionof what they would otherwise cost and in a much reduced time frame.

 Representatives from the Stanford Research Institute and theMITRE Corporation joined Cross in presenting testimony. A copy of his testimonycan be found at the link below.

Petit Scholars program information

Other cores will follow as rates are developed and approved by the Georgia Tech Office of Grants and Contracts Accounting. A phased approach will be used in setting the rates to aid laboratories in planning and provide researchers with an opportunity to make adjustments to budgets.

Beginning in February 2012, users will be charged a small percentage of the cost-based rate for usage. The initial charge to Georgia Tech users for confocal time is anticipated to be $2.75/hr. The rates will be increased in subsequent years but remain highly subsidized by the Petit Institute.

In order to administer the new cost recovery service center, users will access Petit Institute core facilities resources through a new online reservation system, serviced by iLab. The Petit Institute website will remain intact and the only change is that users will register, view and reserve equipment, request services, view bills and enter payment information through the iLab Solutions website.

“By using their scales to control frictional properties,snakes are able to move large distances while exerting very little energy,”said Hamid Marvi, a Mechanical Engineering Ph.D. candidate at Georgia Tech.

While studying and videotaping the movements of 20 differentspecies at Zoo Atlanta, Marvi developed Scalybot 2, a robot that replicatesrectilinear locomotion of snakes. He unveiled the robot this month at theSociety for Integrative & Comparative Biology (SICB) annual meeting inCharleston, S.C.

“During rectilinearlocomotion, a snake doesn’t have to bend its body laterally to move,”explained Marvi. “Snakes lift their ventral scales and pull themselves forwardby sending a muscular traveling wave from head to tail. Rectilinear locomotion isvery efficient and is especially useful for crawling within crevices, aninvaluable benefit for search-and-rescue robots.”  

Scalybot 2 can automatically change the angle of its scales whenit encounters different terrains and slopes. This adjustment allows the robotto either fight or generate friction. The two-link robot is controlled by aremote-controlled joystick and can move forward and backward using four motors.

“Snakes are highly maligned creatures,” said Joe Mendelson, curatorof herpetology at Zoo Atlanta. “I really like that Hamid’s research is showingthe public that snakes can help people.”

Marvi’s advisor is David Hu, an assistant professor in theSchools of Mechanical Engineering and Biology. Hu and his research team areprimarily focused on animal locomotion. They’ve studied how dogs and otheranimals shake water off their bodies and how mosquitos fly through rainstorms.

This isn’t the first time Hu’s lab has looked at snake locomotion.Last summer the team developed Scalybot 1, a two-link climbing robot that replicatesconcertina locomotion. The push-and-pull, accordion-style movement featuresalternating scale activity.

This project is supported by the National Science Foundation (NSF)(Award No. PHY-0848894). The content is solely the responsibility of the principalinvestigators and does not necessarily represent the official views of the NSF.

A new study finds that the anatomy of the heart’s tricuspidvalve can be used to predict the severity of leakage in the valve, which is acondition called tricuspid regurgitation. The study, conducted by researchersfrom the Georgia Institute of Technology and Emory University, found that pulmonaryarterial pressure, the size of the valve opening and papillary muscle position measurementscould be used to predict the severity of an individual’s tricuspidregurgitation.

“By being able to identify and measure an individual’sparticular tricuspid valve anatomical features that we have shown arecorrelated with increased leakage, clinicians should be able to better target their repair efforts and create moredurable repairs,” said Ajit Yoganathan, Regents’ professor in theWallace H. Coulter Department of Biomedical Engineering at Georgia Tech andEmory University.

The study was published in the January issue of the journal Circulation: Cardiovascular Imaging. Funding for this work wasprovided by the American Heart Association and a donation from Tom and ShirleyGurley.

Yoganathan and recent Coulter Department doctoral graduate ErinSpinner teamed with Stamatios Lerakis, a professor of medicine (cardiology), radiologyand imaging sciences at Emory University, to non-invasively collect 3-Dechocardiograms from 64 individuals who exhibited assorted grades of tricuspid leakage.Subjects included 20 individuals with “trace,” 13 with “mild,” 17 with “moderate”and 14 with “severe” tricuspid regurgitation. The subjects with “mild” to“severe” leakage exhibited a mix of isolated right, isolated left, and bothright and left ventricle dilation.

From the 3-D echocardiography images of the heart theycollected, the researchers measured (1) the area of the annulus, which is thefibrous ring that surrounds the tricuspid valve opening; (2) the distancebetween the annulus and the three right ventricle papillary muscles, which keepthe valve shut when the ventricle contracts; and (3) the position of the papillarymuscles with respect to the center of the annulus. The clinicians also measuredpulmonary arterial pressure using standard clinical methods and assessed thegrade of tricuspid regurgitation from “trace” to “severe” with color Dopplerimaging.

In collaboration with Emir Veledar, an assistant professorand statistician in the Rollins School of Public Health at Emory University, theresearchers found statistical differences between individuals with ventricular dilationand the control subjects in the parameters of pulmonary arterial pressure,annulus area and papillary muscle displacement. They also found that all three factors were correlated with the gradeof tricuspid regurgitation.

“This study’s use ofadvanced cardiovascular imaging, and more specifically 3-D echocardiography, providednew insight into the pathophysiology of tricuspid regurgitation and a goodunderstanding as to why current surgical treatments for tricuspid regurgitationare not good enough,” explained Lerakis. “I believe this study will change thefocus and direction of future surgical therapies for tricuspid regurgitationonly to make them better and more durable.”

Based on the findings of this study, said Lerakis, future surgical therapiesshould not only be focused on the tricuspid annulus, but on the entiretricuspid valve apparatus, including the tricuspid valve papillary muscles andtheir three-dimensional location within the apparatus.

Individuals in the study with left ventricle dilation exhibitedsignificant displacement of one of the papillary muscles and patients with both ventricles dilated hadsignificant displacement of two papillary muscles. Subjects with rightventricle dilation showed significant displacement of all three papillarymuscles.  

The researchers also found that patients with a dilated rightventricle were more likely to have a dilated annulus and exhibited the highestpulmonary arterial pressures and highest levels of tricuspid regurgitation. However,not all patients with a dilated right ventricle had significant increases inannulus area, providing evidence that the right ventricle may become dilatedwithout the annulus being affected.

“We think an increase in pulmonary arterial pressure causedgeometric changes in the ventricle, which resulted in alterations to theannulus and papillary muscles,” explainedYoganathan. “The combination of displacement of all three papillarymuscles and annular dilatation may account for the patients with isolated rightventricle dilatation having the largest percentage of severe tricuspid regurgitation.”

Knowing which parameters are responsible for significant tricuspidregurgitation and having a non-invasive imaging technique to measure theseparameters should help clinicians target repairs to the specific cause of an individual’stricuspid leakage, according to Yoganathan.

In future studies, the researchers plan to study papillarymuscle displacements in individuals with specific diseases to see if differentdisease manifestations exhibit different characteristics.

“Although it has long been accepted that pulmonaryhypertension may result in tricuspid regurgitation, this study is one of thefirst to provide a clinical correlation between the two,” said Yoganathan, whois also the Wallace H. Coulter Distinguished Faculty Chair in BiomedicalEngineering. “We want to know whether treating an individual’s pulmonary hypertension,and thus decreasing one’s pulmonary arterial pressure, can reverse thegeometric changes that are causing tricuspid regurgitation and return the annulusand papillary muscles to their original positions.”

Emory University sonographers Jason Higginson, Maria Pernetzand Sharon Howell also contributed to the study.

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Grand Challenges Explorations funds scientists and researchers worldwide to explore ideas that can break the mold in how we solve persistent global health and development challenges. Styczynski’s project is one of 108 Grand Challenges Explorations grants announced in November 2011 as part of Round 7 of the program.

“We believe in the power of innovation—that a single bold idea can pioneer solutions to our greatest health and development challenges,” said Chris Wilson, Director of Global Health Discovery for the Bill & Melinda Gates Foundation. “Grand Challenges Explorations seeks to identify and fund these new ideas wherever they come from, allowing scientists, innovators, and entrepreneurs to pursue the kinds of creative ideas and novel approaches that could help to accelerate the end of polio, cure HIV infection, or improve sanitation.”

Projects that are receiving funding show promise in tackling priority global health issues where solutions do not yet exist. This includes finding effective methods to eliminate or control infectious diseases such as polio and HIV as well as discovering new sanitation technologies.

To learn more about Grand Challenges Explorations, visit www.grandchallenges.org.

Styczynski’s project proposes to create portable, low-cost, bacteria-based genetic circuits to measure blood micronutrient levels without requiring sophisticated instrumentation to perform or read the test. These circuits would provide an inexpensive, rapid method to diagnose nutrition levels, such as vitamins and minerals, in the field.

“Sophisticated equipment is not easily operated in the field, which means that samples must be sent to regional labs for nutritional analysis, resulting in delays of potentially life-saving treatment,” Styczynski says. “We are looking to enable more point-of-care diagnostics using synthetic biology to eliminate the long wait and enable more rapid diagnosis and treatment of those with deficiencies.”

Styczynski received his PhD from the Massachusetts Institute of Technology in 2007. He joined the faculty at Georgia Tech in 2009 after a postdoctoral appointment at the Broad Institute, a world-renowned genomic medicine research center located in Cambridge, Massachusetts.

New findings at Georgia Tech, published in January during GlaucomaAwareness Month, explore one of the many molecular origins of glaucoma andadvance research dedicated to fighting the disease.

Glaucoma is typically triggered when fluid is unable tocirculate freely through the eye’s trabecular meshwork (TM) tissue. Intraocularpressure rises and damages the retina and optic nerve, which causes vision loss.In certain cases of glaucoma, this blockage results from a build-up of theprotein myocilin. Georgia Tech Chemistry and Biochemistry Assistant ProfessorRaquel Lieberman focused on examining the structural properties of these myocilindeposits.

“We were surprised to discover that both genetically defectedas well as normal, or wild-type (WT), myocilin are readily triggered to producevery stable fibrous residue containing a pathogenic material called amyloid,”said Lieberman, whose work was published in the most recent Journal of Molecular Biology.

Amyloid formation, in which a protein is converted from itsnormal form into fibers, is recognized as a major contributor to numerousnon-ocular disorders, including Alzheimer’s, certain forms of diabetes and MadCow disease (in cattle). Scientists are currently studying ways to destroyamyloid fibrils as an option for treating these diseases. Further research,based on Lieberman’s findings, could potentially result in drugs that preventor stop myocilin amyloid formation or destroy existing fibrils in glaucomapatients.

Until this point, amyloids linked to glaucoma had beenrestricted to the retinal area. In those cases, amyloids kill retina cells,leading to vision loss, but don’t affect intraocular pressure.

“The amyloid-containing myocilin deposits we discovered killcells that maintain the integrity of TM tissue,” said Lieberman. “In additionto debris from dead cells, the fibrils themselves may also form an obstructionin the TM tissue. Together, these mechanisms may hasten the increase ofintraocular pressure that impairs vision.”

Together with her research team, Lieberman produced WT andgenetically defected myocilin variants that had been documented in patients whodevelop glaucoma in childhood or early adulthood. The experiments wereconducted in collaboration with Georgia Tech Biology Professor Ingeborg Schmidt-Kreyand Stanford Genetics Professor Douglas Vollrath. Three Georgia Techstudents also participated in the research: Susan Orwig (Ph.D. graduate,Chemistry and Biochemistry), Chris Perry (current undergraduate, Biochemistry)and Laura Kim (master's graduate, Biology).

The National Institutes of Health (award numberR01EY021205 from the National Eye Institute) funded the research. The contentis solely the responsibility of the authors and does not necessarily representthe official views of the National Eye Institute or the National Institutes ofHealth.

The Atlanta-based startup, Clearside Biomedical, plans to develop microinjection technology that will use hollow microneedles to precisely target therapeutics within the eye. If the technique proves successful in clinical trials and wins regulatory approval, it could provide an improved method for treating diseases that affect the back of the eye, including age-related macular degeneration.

The technology was developed in collaboration between the research groups of Mark Prausnitz, a Regents' professor in Georgia Tech's School of Chemical and Biomolecular Engineering, and Henry Edelhauser, a professor in the Department of Ophthalmology at Emory School of Medicine. Research leading to development of the technology was sponsored by the National Institutes of Health (NIH).

"We expect that targeting drug delivery within the eye will be helpful because we should be able to concentrate drugs at the disease sites where they need to act, and keep them away from other locations," said Prausnitz. "This could reduce side effects and possibly also decrease the dose required."

Prior to this development, drugs could be delivered to the retinal tissues at the back of the eye in three indirect ways: (1) injection by hypodermic needle into the eye's vitreous humor, the gelatinous material that fills the eyeball, (2) eye drops, which are limited in their ability to reach the back of the eye, and (3) pills taken by mouth that expose the whole body to the drug.

The technology developed by Georgia Tech and Emory uses a hollow micron-scale needle to inject therapeutics into the suprachoroidal space located between the outer surface of the eye -- known as the sclera -- and the choroid -- a deeper layer that provides nutrients to the rest of the eye. Preclinical research has demonstrated that fluid can flow between the two layers, where it can spread out to the entire eye, including structures such as the retina that are now difficult to reach.

By targeting this suprachoroidal space using microscopic needles, the researchers believe they can reduce trauma to the eye, make drugs more effective and reduce complications. The new delivery method could help advance a new series of drugs being developed to target the retina, choroid and other structures in the back of the eye.

"This is a significant advance in the field of ophthalmology," said Edelhauser. "Until now, it has been difficult to target drug delivery to specific locations within the eye. This new microneedle technology enables precise drug targeting to the suprachoroidal space and other locations within the eye."

In research reported in the January 2011 issue of the journal Pharmaceutical Research, the Georgia Tech-Emory team demonstrated for the first time that this technique can be used to deliver nanoparticles and microparticles to specific parts of the eye. In later research, they also showed that microneedle injections into the suprachoroidal space rapidly resulted in concentrations of drugs and particles that could be maintained for several months.

Between two and three million eye injections are made each year, many of them to treat age-related macular degeneration (AMD). The researchers believe that the microneedle-based technique could be useful for treating both AMD and glaucoma, as well as other ocular conditions related to diabetes.

The $4 million in funding for Clearside Biomedical will come from Hatteras Venture Partners, a venture capital firm based in Research Triangle Park, N.C. Hatteras focuses on seed and early-stage investments in companies developing products in biopharmaceutical, medical device, diagnostic and related human health areas.

"Clearside Biomedical represents an ideal fit for Hatteras Discovery as the platform technology is highly innovative, based on elegant science and the lead product is expected to be in clinical trials in the United States in less than 18 months," said Christy Shaffer, Ph.D., venture partner and managing director of the Hatteras Discovery Fund.

So far, the technique has been tested only in animals. The Hatteras funding will allow the company to conduct additional efficacy and safety testing needed to seek regulatory approval. The company's first product is expected to address macular edema and retinal vein occlusion.

Clearside was formed with the assistance of Georgia Tech's VentureLab program, which helped obtain early-stage seed funding from the Georgia Research Alliance. Georgia Tech VentureLab also helped the founders connect with the company's president and CEO, Daniel White, a veteran ophthalmic entrepreneur. Before joining Clearside, White was a co-founder of Alimera Sciences, an Atlanta company that is developing ophthalmic pharmaceuticals.

Two researchers from the Prausnitz lab who have been involved in development of the ocular drug delivery technique will also join the company. They are Samirkumar Patel, a postdoctoral researcher and Vladimir Zarnitsyn, a research scientist.

Research leading to the development of the technology has been supported by the National Institutes of Health (NIH). The content of this article is solely the responsibility of the principal investigators and does not necessarily represent the official view of the NIH.

Henry Edelhauser, Samirkumar Patel, Mark Prausnitz, Vladimir Zarnitsyn, Emory University and Georgia Tech have financial interests in Clearside Biomedical and its ocular platform. Edelhauser, Patel, Prausnitz and Zarnitsyn own equity in Clearside and the terms of this arrangement have been reviewed and approved by Emory University or Georgia Tech in accordance with their conflict of interest policies.

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Writer: John Toon

Three of the new AAAS Fellows at Georgia Tech hail from the College of Engineering and one is on the faculty in the College of Computing. The Fellows were announced today in the journal Science and will be honored at the Fellows Forum, held Feb. 18 at the AAAS Annual Meeting in Vancouver, Canada.

The new AAAS Fellows at Georgia Tech are:

Ali Adibi, professor of electrical and computer engineering, who was honored for his “distinguished contributions to the fields of integrated nanophotonics, photonic crystals, and volume holography."

David Bader, professor of computational science and engineering in the College of Computing, who earned the distinction for “distinguished contributions to the field of computational science and engineering.”

Robert Butera, professor of electrical and computer engineering who also holds a joint appointment in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, was named Fellow “for advances in computational neuroscience and neurotechnology, promoting engineering through society, editorial, and university leadership, and contributing to STEM policy and educational initiatives."

Paul Steffes, professor of electrical and computer engineering, who earned the distinction for “contributions to the understanding of planetary atmospheres through innovative microwave measurements."

AAAS is an international non-profit organization dedicated to advancing science around the world by serving as an educator, leader, spokesperson and professional association. AAAS publishes the journal Science as well as many scientific newsletters, books and reports, and spearheads programs that raise the bar of understanding for science worldwide. The four Georgia Tech faculty members were among 539 Fellows elected by the AAAS Council in November. 

The Petit Institute Above and Beyond Awards are selected by the Faculty Steering Committee and given to team-based individuals who demonstrate exemplary service to the institute and contribute to its collegial, collaborative environment.  Three awards are given each year to a senior faculty member, a pre-tenure faculty member and a staff member.

Loren Williams, professor in Chemistry and Biochemistry, has contributed to the Petit Institute significantly this year. Williams is the director of one of the Petit Institute interdisciplinary research centers, RiboEvo.  RiboEvo is a NASA-funded center which is focused on integrated interdisciplinary research and education in astrobiology. As part of the center’s activities, Williams voluntarily participated in the Buzz on Biotechnology high school open house where his center hosted two booths, one with a 3-D visualization of DNA, RNA using PyMol and another demonstration showcasing the use of liquid nitrogen in cryogenics and molecular biology. In addition, Williams organized the 2011 Suddath Symposium and participated in several Petit Institute activities including the Industry Partners Symposium dinner and the Bio-Center Poster Session. Williams also sits on the core facilities steering committee. Williams will have an equally busy 2012 as he is chair of the Astrobiology Science Conference which will attract over 700 scientists to Atlanta and Georgia Tech next year.

Todd Sulchek, assistant professor in Mechanical Engineering, was nominated for his participation and support of the Petit Scholars program over the last several years and for consistently being an active community citizen. Sulchek has participated in many Petit Institute-related events, seminars and community-wide poster sessions.  In addition, Sulchek received a NSF CAREER Award for his proposal titled: "Understanding Multivalent Biological Bonds for Biosensing Applications."  Sulchek will continue to support Petit Institute activities in 2012 as he is scheduled to give a seminar for the Petit Institute’s IBB Breakfast Club seminar series in February.

Colly Mitchell, special program coordinator for marketing and communications,has been working for the Petit Institute since 2007. In 2008, she began tomanage the Petit Scholars program.  At the time Mitchell took over, the program wasdeclining.  Over the course of thelast 3 years, she has played a key role in improving the number and quality ofthe applications and in 2011 the program is thriving.  During her tenure at the Petit Institute, Mitchell has made acomplex job look easy by supporting a variety of Petit Institute events forgroups ranging from students to high-profile donors and administrators. Inaddition, she is responsible for various communication activities, includingdisplay of news and events on the atrium’s flat screen TV and the institute’swebsite. Perhaps even more impressively, she manages all of this on a part-timebasis and does so with a calm demeanor, a constant smile and an easyprofessionalism that earns her the respect and admiration of her colleagues.  

Bellamkonda directs the Neurological Biomaterials and Cancer Therapeutics Laboratory, a part of the Laboratory for Neuroengineering in the joint Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory. He also serves as associate vice president within the Office of the Executive Vice President for Research (EVPR), directs a T32 training grant called Rational Design of Biomaterials, directs a Graduate Leadership Program for BioE/BME graduate students and is a Georgia Cancer Coalition Distinguished Scholar.  

Current research projects in the Neurological Biomaterials and Cancer Therapeutics Laboratory include: developing scaffolds for peripheral nerve regeneration and interfacing; developing vehicles for contrast agents and receptor-targeted nano-scale drug delivery for the treatment of malignant tumors; and engineering a system for tumor exvasion. He is also leading a research team exploring interfacing technologies that will better integrate external electronics to the nervous system. In addition to the Flanagan endowment, Bellamkonda’s research is funded by grants from NIH, NSF, the Coulter Foundation, the Georgia Cancer Coalition, and Ian's Friend's Foundation.

A survey of more than 200 human embryonic stem cell researchers in the United States found that nearly four in ten researchers have faced excessive delay in acquiring a human embryonic stem cell line and that more than one-quarter were unable to acquire a line they wanted to study.

"The survey results provide empirical data to support previously anecdotal concerns that delays in acquiring or an inability to acquire certain human embryonic stem cell lines may be hindering stem cell science in the United States," said Aaron Levine, an assistant professor in the School of Public Policy in the Ivan Allen College of Liberal Arts at the Georgia Institute of Technology.

Results of the survey were published in the December issue of the journal Nature Biotechnology. Funding for the study was provided by the Kauffman Foundation's Roadmap for an Entrepreneurial Economy Program.

Levine administered the web-based survey in November 2010 to more than 1,400 stem cell scientists working at U.S. academic and non-profit medical research institutions. Almost 400 respondents from 32 states completed the survey. Of those, 205 respondents reported using human embryonic stem cells in their research, and their responses were used in this study.

The surveyed scientists cited four main reasons for their problems accessing human embryonic stem cell lines: difficulty obtaining material transfer agreements, failure to acquire research approval from internal institutional oversight committees, cell line owners that were unwilling to share and federal policy considerations.

"Bureaucratic challenges may be inevitable in this ethically contentious and politically sensitive field, but policymakers should attempt to mitigate these issues by doing things like encouraging institutions to accept third-party ownership verification and providing clearer guidance on human embryonic stem cell research not eligible for federal funding," said Levine, who is also a member of the Georgia Tech Institute for Bioengineering and Bioscience.

The broad patents assigned to the initial inventors of the method used to isolate embryonic stem cells and numerous narrower patents claiming specific human embryonic stem cell-related techniques are also factors complicating access to human embryonic stem cell lines, according to Levine.

When survey respondents were asked how many of the more than 1,000 existing human embryonic stem cell lines they used, 76 percent reported using three or fewer lines and 54 percent reported using two or fewer lines in their research. More than half of the 130 respondents cited access issues as a major reason they chose to use specific cell lines in their research.

"These results illustrate that many human embryonic stem cell scientists in the United States are not conducting comparative studies with a diverse set of human embryonic stem cell lines, which raises concern that at least some results are cell-line specific rather than broadly applicable," said Levine. "Federal and state funding agencies may want to consider encouraging research using multiple diverse human embryonic stem cell lines to improve the reliability of research results."

Embryonic stem cell lines are being used to develop new cellular therapies for various diseases, to screen for new drugs and to better understand inherited diseases. It's crucial that diverse lines are available for this research to ensure that all individuals benefit from the results.

While availability was cited as the most common factor affecting scientists' choices regarding which cell lines to use, other considerations included suitability for a specific project, familiarity with specific lines, a desire to reduce complications in the laboratory, cost, the extent of relevant literature and the preferences of scientists' colleagues.

Three of the initial human embryonic stem cell lines derived at the University of Wisconsin in the late 1990s were the lines most commonly used by respondents. Cell lines H1, H9 and H7 were used by 79, 68 and 26 percent of respondents, respectively. Scientists also reported using more than 100 other lines, but each of these was used by fewer than 12 percent of respondents.

"Other research communities in the life sciences have experienced material access problems and they addressed them, in part, by creating centralized information and data sharing hubs, including public DNA sequence databases, tissue banks and mouse repositories. The stem cell research community has taken promising steps in this direction, but this analysis should encourage the community to continue and, if possible, accelerate these efforts," added Levine.

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Stepp,a Computer Science major in the College of Computing, is a former national andregional winner of the Aspirations in ComputingAward. Champion is an assistantprofessor in the School of Chemical and Biomolecular Engineering.

TheOffice of Public Engagement is hosting the event, and White House PolicyOffices will use the discussions to create best practices for future education initiatives.

A new study provides a mechanistic explanation of how ribonucleotides embedded in genomic DNA are recognized and removed from cells. Two mechanisms, enzymes called ribonucleases (RNases) H and the DNA mismatch repair system, appear to interplay to root out the RNA components.

"We believe this is the first study to show that cells utilize independent repair pathways to remove mispaired ribonucleotides embedded in chromosomal DNA, which can be sources of genetic modification if not removed," said Francesca Storici, an assistant professor in the School of Biology at the Georgia Institute of Technology. "The results also highlight a novel case of genetic redundancy, where the mismatch repair system and RNase H mechanisms compete with each other to remove misincorporated ribonucleotides and restore DNA integrity."

The findings were reported Dec. 4, 2011 in the advance online publication of the journal Nature Structural & Molecular Biology. The research was supported by the Georgia Cancer Coalition, National Science Foundation and Georgia Tech Integrative BioSystems Institute.

Storici and Georgia Tech biology graduate students Ying Shen and Kyung Duk Koh conducted the study in collaboration with Bernard Weiss, a professor emeritus in the Department of Pathology and Laboratory Medicine at Emory University.

"We wanted to understand how cells of the bacterium Escherichia coli and the yeast Saccharomyces cerevisiae tolerate the presence of different ribonucleotides embedded in their genomic DNA. We found that the structure of a ribonucleotide tract embedded in DNA influenced its ability to cause genetic mutations more than the tract's length," said Storici.

With double-stranded DNA, when wrong bases are paired or one or few nucleotides are in excess or missing on one of the strands, a mismatch is generated. If mismatches are not corrected, they can lead to mutations.

The researchers found that single mismatched ribonucleotides in chromosomal DNA were removed by either the mismatch repair system or RNase H type 2. Mismatched ribonucleotides in the middle of at least four other ribonucleotides required RNase H type 1 for removal.

"We were excited to find that a DNA repair mechanism like mismatch repair was activated by RNA/DNA mismatches and could remove ribonucleotides embedded in chromosomal DNA," explained Storici. "In future studies, we plan to test whether other DNA repair mechanisms, such as nucleotide-excision repair and base-excision repair, can also locate and remove ribonucleotides in DNA."

Using gene correction assays driven by short nucleic acid polymers called oligonucleotides, the researchers showed that when ribonucleotides embedded in DNA were not removed, they served as templates for DNA synthesis and produced a mutation in the DNA. If both the mismatch repair system and RNase H repair mechanisms are disabled, ribonucleotide-driven gene modification increased by a factor of 47 in the yeast and 77,000 in the bacterium.

Defects in the mismatch repair system are known to predispose a person to certain types of cancer. Because the mismatch repair system is conserved from unicellular to multicellular organisms, such as humans, this study's findings open up the possibility that defects in the mismatch repair system could have consequences more critical than previously thought given the newly identified function of mismatch repair to target RNA/DNA mispairs.

The results also provide new information on the capacity of RNA to play an active role in DNA editing and remodeling, which could be the basis of an unexplored process of RNA-driven DNA evolution.

This project was supported by the National Science Foundation (NSF) (Award No. MCB-1021763). The content is solely the responsibility of the principal investigators and does not necessarily represent the official views of the NSF.

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"We offered Georgia Aquarium leaders accurate predictions on how the new AT&T Dolphin Tales exhibit would impact guest flow within the aquarium and how to optimize the operations logistics, efficiency and show schedules for the new exhibit," said Eva K. Lee, a professor in the H. Milton Stewart School of Industrial and Systems Engineering at Georgia Tech.

The new 84,000-square-foot AT&T Dolphin Tales attraction, which opened in April 2011, includes a theater with performances of Atlantic Bottlenose dolphins in a Broadway-style production with live actors and trainers, all set to an orchestral soundtrack. The exhibit also features a lobby area where visitors can be face-to-face with the dolphins through a 25-foot viewing window.

"We knew that managing the flow of guests through the new AT&T Dolphin Tales exhibit was going to be more difficult than the other aquarium galleries because guests would be entering and exiting the exhibit through the same space," said Brian Davis, director of education and guest programs at the Georgia Aquarium. "The logistical predictions and recommendations Georgia Tech provided us were extremely accurate and enabled us to ensure an amazing guest experience while remaining fiscally responsible."

To provide recommendations to the Georgia Aquarium on how to optimize visitor flow through the new exhibit, Lee and Georgia Tech graduate student Chien-Hung Chen created RealOpt-ABM, a large-scale modeling and decision support software suite that could model guest movement through the entire aquarium.

With this software, the researchers predicted guest flow through the new exhibit and the impact of the new exhibit to surrounding areas and overall visitor flow. They were also able to determine the best strategies for show scheduling, resource allocation, space usage, and theater loading and unloading. RealOpt-ABM produced recommendations that were implemented for operations design of the new exhibit, according to Joe Handy, vice president of guest experience at the Georgia Aquarium.

According to Lee, the software's success lies in its integrated simulation and optimization approach and its inclusion of human cognitive and behavioral elements. The software's computational speed also allowed for rapid solution strategies and on-the-fly reconfigurations. Facility layout, physical design and activities at specific points of interest were captured in sub-models, which were aggregated and coupled to form the overall model.

"RealOpt-ABM incorporated advances in agent-based simulation that capture the stochastic nature of the events within the aquarium, optimization of resource allocation and show schedules, and modeling of human cognitive decisions that affect show preference and guest behavior," explained Lee.

To validate the model, Lee, research engineer Niquelle Brown and 10 Georgia Tech students analyzed guest flow and behavior patterns in the entire aquarium before the new exhibit opened. Through time-motion studies in 2010, they collected guest flow data and captured the decisions guests made, such as turning left or right when they arrived at an intersection and how long guests spent in each exhibit area. The data showed that guest movement changed based on the time of day and what time guests arrived at the museum.

Using RealOpt-ABM, the researchers accurately predicted the amount of time required to load and unload the AT&T Dolphin Tales theater, depending on the number of guests, which led to a recommendation that performances be separated by at least 90 minutes to minimize congestion. The researchers also recommended that on days with fewer than 6,000 aquarium attendees, only two shows should be offered. This recommendation was based on the need to maintain the comfort and health of the dolphins while minimizing unnecessary operations costs.

RealOpt-ABM also detailed the optimal number and location of ticket scanners and traffic controllers and the best time to open the theatre doors so that the waiting time and queue length were acceptable. The study also predicted that unless other provisions were made, a large percentage of the new exhibit's lobby area would be occupied by baby strollers that were not allowed in the theater. Lee's team recommended the creation of valet stroller parking in the main lobby of the aquarium to avoid logistics bottlenecks and congestion in the exhibit lobby area.

This logistics research project is one of six finalists for the 2011 Daniel H. Wagner Prize for Excellence in Operations Research Practice, which is given by the Institute for Operations Research and the Management Sciences (INFORMS). The winner will be selected on Nov. 14 at the INFORMS Annual Meeting, following presentations by the finalists.

"Effective strategies for managing guest flow are imperative for the successful operation of the aquarium and we trust Georgia Tech's logistics advice 100 percent," said Davis. "As the Georgia Aquarium continues to grow and expand, we will always look to Georgia Tech's expertise to maximize the experience for our guests."

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Grand Challenges Explorations funds scientists and researchers worldwide to explore ideas that can break the mold in how we solve persistent global health and development challenges. The Georgia Tech/CDC project is one of 110 Grand Challenges Explorations grants announced November 7th.

"We believe in the power of innovation -- that a single bold idea can pioneer solutions to our greatest health and development challenges," said Chris Wilson, director of global health discovery for the Bill & Melinda Gates Foundation. "Grand Challenges Explorations seeks to identify and fund these new ideas wherever they come from, allowing scientists, innovators and entrepreneurs to pursue the kinds of creative ideas and novel approaches that could help to accelerate the end of polio, cure HIV infection or improve sanitation."

Projects that are receiving funding show promise in tackling priority global health issues where solutions do not yet exist. This includes finding effective methods to eliminate or control infectious diseases such as polio and HIV as well as discovering new sanitation technologies.

The goal of the Georgia Tech/CDC project is to demonstrate the scientific and economic feasibility for using microneedle patches in vaccination programs aimed at eradicating the polio virus. Current vaccination programs use an oral polio vaccine that contains a modified live virus. This vaccine is inexpensive and can be administered in door-to-door immunization campaigns, but in rare cases the vaccine can cause polio. There is an alternative injected vaccine that uses killed virus, which carries no risk of polio transmission, but is considerably more expensive than the oral vaccine, requires refrigeration for storage and must be administered by trained personnel. To eradicate polio from the world, health officials will have to discontinue use of the oral vaccine with its live virus, replacing it with the more expensive and logistically-complicated injected vaccine.

Prausnitz and his CDC collaborators believe the use of microneedle patches could reduce the cost and simplify administration of the injected vaccine. Use of the patches, which carry vaccine into the body by dissolving into the skin, could eliminate the need for administration by highly-trained personnel and the "sharps" disposal problems of traditional hypodermic needles. Because skin administration produces an immune response with smaller doses of vaccine than traditional deep intramuscular injection, the researchers expect to reduce the per-person cost of vaccine. And by incorporating dried vaccine into the microneedles, they hope to eliminate the need for vaccine refrigeration -- a challenge in remote areas of the world.

"We envision vaccination campaigns in which minimally-trained personnel go door-to-door administering microneedle patches rather than oral polio vaccine," Prausnitz explained. "Our goal for this study will be to provide the data to scientifically justify moving the microneedle patch for polio vaccination into a human trial."

In research that will complement the Grand Challenges Exploration grant, Prausnitz and his team have also received funding from the World Health Organization (WHO) to support development of the polio vaccine application for microneedle patches. And in a project sponsored by the U.S. National Institutes of Health (NIH), Prausnitz and other Georgia Tech researchers are collaborating with Emory University scientists on development of a microneedle patch for administering flu vaccine.

About Grand Challenges Explorations: Grand Challenges Explorations is a US $100 million initiative funded by the Bill & Melinda Gates Foundation. Launched in 2008, Grand Challenge Explorations grants have already been awarded to nearly 500 researchers from over 40 countries. The grant program is open to anyone from any discipline and from any organization. The initiative uses an agile, accelerated grant-making process with short, two-page online applications and no preliminary data required. Initial grants of $100,000 are awarded two times a year. Successful projects have an opportunity to receive a follow-on grant of up to US $1 million. To learn more about Grand Challenges Explorations, visit www.grandchallenges.org.

About The Georgia Institute of Technology: The Georgia Institute of Technology is one of the world's premier research universities, ranked second among all U.S. colleges and universities in the amount of engineering research conducted. Ranked seventh among U.S. News & World Report's top public universities, Georgia Tech's more than 20,000 students are enrolled in its Colleges of Architecture, Computing, Engineering, Liberal Arts, Management and Sciences. Georgia Tech is among the nation's top producers of women and minority engineers. The Institute offers research opportunities to both undergraduate and graduate students and is home to more than 100 interdisciplinary units plus the Georgia Tech Research Institute.

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The research team lead by Georgia Tech Professor of BiologyJohn McDonald has verified that while the DNA sequence of genes between humansand chimpanzees is nearly identical, there are large genomic “gaps” in areas adjacentto genes that can affect the extent to which genes are “turned on” and “turnedoff.” The research shows that these genomic “gaps” between the two species are predominantlydue to the insertion or deletion (INDEL) of viral-like sequences calledretrotransposons that are known to comprise about half of the genomes of bothspecies. The findings are reported in the most recent issue of the online,open-access journal Mobile DNA.

“These genetic gaps have primarily been caused by theactivity of retroviral-like transposable element sequences,” said McDonald. “Transposableelements were once considered ‘junk DNA’ with little or no function. Now itappears that they may be one of the major reasons why we are so different fromchimpanzees.”

McDonald’s research team, comprised of graduate students NaliniPolavarapu, Gaurav Arora and Vinay Mittal, examined the genomic gaps in bothspecies and determined that they are significantly correlated with differencesin gene expression reported previously by researchers at the Max PlankInstitute for Evolutionary Anthropology in Germany.

“Our findings are generally consistent with the notion that themorphological and behavioral differences between humans and chimpanzees arepredominately due to differences in the regulation of genes rather than todifferences in the sequence of the genes themselves,” said McDonald.

The current analysis of the genetic differences betweenhumans and chimpanzees was motivated by the group’s previously publishedfindings (2009) that the higher propensity for cancer in humans vs. chimpanzeesmay have been a by-product of selection for increased brain size in humans.

The study found that applying mechanical forces to an injury site immediately after healing began disrupted vascular growth into the site and prevented bone healing. However, applying mechanical forces later in the healing process enhanced functional bone regeneration. The study’s findings could influence treatment of tissue injuries and recommendations for rehabilitation.

“Our finding that mechanical stresses caused by movement can disrupt the initial formation and growth of new blood vessels supports the advice doctors have been giving their patients for years to limit activity early in the healing process,” said Robert Guldberg, a professor in the George W. Woodruff School of Mechanical Engineering at the Georgia Institute of Technology. “However, our findings also suggest applying mechanical stresses to the wound later on can significantly improve healing through a process called adaptive remodeling.”

The study was published last month in the journal Proceedings of the National Academy of Sciences. The research was supported by the National Institutes of Health, the Armed Forces Institute of Regenerative Medicine and the U.S. Department of Defense.

Because blood vessel growth is required for the regeneration of many different tissues, including bone, Guldberg and former Georgia Tech graduate student Joel Boerckel used healing of a bone defect in rats for their study. Following removal of eight millimeters of femur bone, they treated the gap with a polymer scaffold seeded with a growth factor called recombinant human bone morphogenetic protein-2 (rhBMP-2), a potent inducer of bone regeneration. The scaffold was designed in collaboration with Nathaniel Huebsch and David Mooney from Harvard University.

In one group of animals, plates screwed onto the bones to maintain limb stability prevented mechanical forces from being applied to the affected bone. In another group, plates allowed compressive loads along the bone axis to be transferred, but prevented twisting and bending of the limbs. The researchers used contrast-enhanced micro-computed tomography imaging and histology to quantify new bone and blood vessel formation.

The experiments showed that exerting mechanical forces on the injury site immediately after healing began significantly inhibited vascular growth into the bone defect region. The volume of blood vessels and their connectivity were reduced by 66 and 91 percent, respectively, compared to the group for which no force was applied. The lack of vascular growth into the defect produced a 75 percent reduction in bone formation and failure to heal the defect.

But the study found that the same mechanical force that hindered repair early in the healing process became helpful later on.

When the injury site experienced no mechanical force until four weeks after the injury, blood vessels grew into the defect and vascular remodeling began. With delayed loading, the researchers observed a reduction in quantity and connectivity of blood vessels, but the average vessel thickness increased. In addition, bone formation improved by 20 percent compared to when no force was applied, and strong tissue biomaterial integration was evident.

“We found that having a very stable environment initially is very important because mechanical stresses applied early on disrupted very small vessels that were forming,” said Guldberg, who is also the director of the Petit Institute for Bioengineering and Bioscience at Georgia Tech. “If you wait until those vessels have grown in and they’re a little more mature, applying a mechanical stimulus then induces remodeling so that you end up with a more robust vascular network.”

The study’s results may help researchers optimize the mechanical properties of tissue regeneration scaffolds in the future.

“Our study shows that one might want to implant a material that is stiff at the very beginning to stabilize the injury site but becomes more compliant with time, to improve vascularization and tissue regeneration,” added Guldberg.

Georgia Tech mechanical engineering graduate student Brent Uhrig and postdoctoral fellow Nick Willett also contributed to this research.

The $3 million NSF-funded IGERT was awarded to Georgia Tech in 2010 to educate and train the first generation of PhD students in the translation and commercialization of stem cell technologies for diagnostic and therapeutic applications. The current state of the field of stem cell research offers a unique opportunity for engineers to contribute significantly to the generation of robust, reproducible and scalable methods for phenotypic characterization, propagation, differentiation and bioprocessing of stem cells.

Directed by Co-Principal investigators, Todd C. McDevitt, PhD, associate professor in the Wallace H. Coulter Department of Biomedical Engineering, and Robert M. Nerem, PhD, professor emeritus in the George W. Woodruff School of Mechanical Engineering, this grant provides a unique training opportunity to top engineering graduate students looking to understand how to scale and control stem cells into clinically relevant numbers. The goal, to train the next generation of experts in this new field of stem cell biomanufacturing for the development of stem cell technologies, diagnostics, and therapies.

Catalyzed by a surge of activity in the late 1990s, advances in stem cell biology over the past decade have continued to accelerate at a rapid pace. The manufacturing industry is expanding with commercial development of stem cell products projected to be $10 billion within the next 6-8 years. Moreover, the transformation from discoveries in stem cell biology to viable cellular technologies has enormous promise to revolutionize a range of applications for many aspects of society. As a result, stem cell biomanufacturing is on the verge of broadly impacting regenerative medicine, drug discovery and development, cell-based diagnostics and cancer.

Earlier this year, United States President Barack Obama asked Georgia Tech’s President G.P. “Bud” Peterson to join the Advanced Manufacturing Partnership steering committee to revolutionize manufacturing in the United States. Along with other industry and university representatives, the purpose of this committee is to identify and invest in the key emerging technologies, such as information technology, biotechnology and nanotechnology to help U.S. manufacturers improve cost, quality and speed of production in order to remain globally competitive. The stem cell biomanufacturing industry need look no further than President Peterson’s backyard for future experts in stem cell biomanufacturing.

“I have received dozens of calls and emails from industry looking for graduates of this program because of the uniqueness of the training and the need for manufacturing expertise,” stated McDevitt. “Georgia Tech has a real opportunity to become a leader in this emerging field and begin to answer questions about down-stream processes so that when the first clinical therapies are discovered, scientists are prepared to be able to respond with cells in the quantity and quality that will be needed for treatment.”

The Stem Cell Biomanufacturing IGERT is further catalyzed by the Stem Cell Engineering Center, which was also established in 2010 and brings together research laboratories from all over the state of Georgia to discuss and develop collaborative opportunities for research labs engineering novel stem cell based technologies, therapies, and diagnostics.

Georgia Tech's Stem Cell Biomanufacturing IGERT award will train over 30 graduate students in the first 5 years of the program. The IGERT offers a core curriculum in stem cell engineering and analytical design processes coupled with elective tracks in advanced technologies, public policy, ethics or entrepreneurship.

2011 Trainees 
Tom Bongiorno – George W. Woodruff School of Mechanical Engineering, Advisor – Todd Sulchek
Rob Dromms – School of Chemical and Biomolecular Engineering, Advisor – Mark Styczynski
Devon Headen – Wallace H. Coulter Department of Biomedical Engineering, Advisor – Andres Garcia
Greg Holst – George W. Woodruff School of Mechanical Engineering, Advisor – Craig Forest
Torri Rinker – Wallace H. Coulter Department of Biomedical Engineering, Advisor – Johnna Temenoff
Shalini Saxena – School of Material Science & Engineering, Advisor – Andrew Lyon
Josh Zimmerman – Wallace H. Coulter Department of Biomedical Engineering, Advisor – Todd McDevitt

2010 Trainees
Amy Cheng – George W. Woodruff School of Mechanical Engineering, Advisor – Andrés García
Alison Douglas – Wallace H. Coulter Department of Biomedical Engineering, Advisor – Thomas Barker
Jennifer Lei – George W. Woodruff School of Mechanical Engineering, Advisor – Johnna Temenoff
Douglas White – Wallace H. Coulter Department of Biomedical Engineering, Advisors – Melissa Kemp & Todd McDevitt
Jenna Wilson – Wallace H. Coulter Department of Biomedical Engineering, Advisor – Todd McDevitt

Researchers at the Georgia Institute of Technology are working on communication solutions for networks so futuristic they don’t even exist yet.

The team is investigating how to get devices a million times smaller than the length of an ant to communicate with one another to form nanonetworks. And they are using a different take on “cellular” communication—namely how bacteria communicate with one another—to find a solution.

Georgia Tech Professor of Electrical and Computer Engineering Ian Akyildiz and his research team—Faramarz Fekri, professor of electrical and computer engineering; Craig Forest, assistant professor of mechanical engineering; Brian Hammer, assistant professor of biology; and Raghupathy Sivakumar, professor of electrical and computer engineering—were recently awarded a $3 million grant from the National Science Foundation for the project.

Over the next four years, the team will study how bacteria communicate with each other on a molecular level to see if the same principles can be applied to how nanodevices will one day communicate to form nanoscale networks.

If the team is successful, the applications for intelligent, communicative nanonetworks could be wide ranging and potentially life changing.

“The nanoscale machines could potentially be injected into the blood, circulating in the body to detect viruses, bacteria and tumors,” said Akyildiz, principal investigator of the study. “All these illnesses—cancer, diabetes, Alzheimer’s, asthma, whatever you can think of—they will be history over the years. And that’s just one application.”

Nanotechnology is the study of manipulating matter on an atomic and molecular scale, where unique phenomena enable novel applications not feasible when working with bulk materials or even single atoms or molecules. Generally, nanotechnology deals with developing materials, devices or structures possessing at least one dimension sized from 1 to 100 nanometers. A nanometer is one billionth of a meter.

Most of the nanoscale devices that currently exist are primitive, Akyildiz said, but with communication the devices could collaborate and have a collective intelligence.

That’s the question researchers are tackling—how would such nanonetworks communicate? Because of their size, classical communication solutions will not work. The team is turning its attention to nature for inspiration.

“We realized that nature already has all these nanomachines. Human cells are perfect examples of nanomachines and the same is true of bacteria,” Akyildiz said. “And so, the best bet for us is to look at bacteria behavior and learn how bacteria are communicating and use those natural solutions to develop solutions for future communication problems.” 

Bacteria use chemical signals to communicate with one another through a process called quorum sensing, which allows a population of single-celled microbes to work like a multicellular organism. Originally discovered several decades ago in unusual bioluminescent marine bacteria, it is now believed that all bacteria “talk” to one another with chemical signals.

Microbiologists are beginning to learn the “languages” bacteria speak and what activities are controlled by this cellular communication. Many disease-causing pathogenic bacteria use quorum sensing to turn on their toxins and other factors to use against a host. Potential therapeutics are currently being developed by some researchers that are designed to disrupt quorum sensing by infectious bacteria. 

“A single pathogenic bacterium in your body is unlikely to kill you,” said Hammer, a microbial geneticist. “But since they communicate, the entire group orchestrates this coordinated behavior using chemical communication and the end result is that they work as a group to kill their host. So can we use that same information in a positive way by harnessing and understanding the limits of the communication?”

Georgia Tech researchers Hammer and Forest will focus on experimentation to better understand the elements of bacterial communication, and then work with the electrical and computer engineering experts on the team to translate their findings into a possible communication model for nanonetworks.

“What can bacteria say and hear, and how do they communicate to one another? Information theory research will examine these issues to pave the way for this new networking paradigm," said Fekri, professor of electrical and computer engineering. “This is really revolutionary research. No one has looked at these issues before. We are dealing with the big challenges. It’s going to require a lot of talent and hard work to address them."

The project is expected to pave the way for research in nanoscale communication. The range of applications of nanonetworks is incredibly wide, from intra-body networks for health monitoring, cancer detection or drug delivery to chemical and biological attack prevention systems.

At the end of four years, the team hopes to demonstrate the basic and fundamental underlying theories for communication of nanodevices. They also hope to develop a simulation tool for the public to use to see how machines can mimic bacteria communication, which will hopefully attract other researchers to get involved in investigating this area further.

“Existing paradigms for network protocols and algorithms do not apply anymore. This is beyond the frontiers of networking research,” said Sivakumar.  “It’s really something that could change things and no one has done this before.”

A great strength of the Georgia Tech research team is its interdisciplinary nature.

“We’re excited to combine science and engineering as well as our respective tool sets, whether genetic engineering, genetic sensing or network communications theory to tackle this system-level problem—this grand challenge in nanotechnology,” said Forest, an expert in biomedical engineering.

"By developing, testing and refining medical devices specifically for children, we hope to produce safer, more effective devices that will improve their lives," said Barbara Boyan, the Price Gilbert, Jr. Chair in Tissue Engineering in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.

The consortium will be led by Boyan, along with consortium co-directors Kevin Maher, a cardiologist and researcher specializing in pediatrics with appointments at the Children's Healthcare of Atlanta Sibley Heart Center and Emory University, and Wilbur Lam, a pediatric hematologist/oncologist and bioengineer with appointments at Emory, the Aflac Cancer Center of Children's Healthcare of Atlanta and Georgia Tech.

Historically, devices designed for adults have been used in children. However, differences in body size and immune system responses between adults and children, and the lack of appropriate models to assess how a device might function in a growing child, can result in poor device performance and responses that are less than optimal.

"There is little information as to what devices are working well for children and what complications occur," explained Boyan, who is also a Georgia Research Alliance Eminent Scholar. "In addition, the high cost of clinical trials for a small market like pediatrics has made conducting pediatric trials cost-prohibitive for many manufacturers."

The consortium will try to reduce these barriers by creating a product development pathway that will provide support for commercialization of devices for pediatric health care from initial concept to the completed product.

To do this, the consortium will build on partnerships the institutions have with the Georgia Tech Translational Research Institute for Biomedical Engineering and Science (TRIBES), which focuses on the need for engineering systems that result in commercial products; the Global Center for Medical Innovation (GCMI), which includes a prototyping design and development facility; and the Advanced Technology Development Center (ATDC) at Georgia Tech, a startup accelerator that helps Georgia technology entrepreneurs launch and build successful companies. Consortium institutions will also partner with SJTRI and the National Institutes of Health-sponsored Atlanta Clinical & Translational Science Institute (ACTSI) for pre-clinical, first-in-child testing and clinical assessments.

Additional consortium leadership will be provided by Franklin Bost, professor and director of design instruction in the Coulter Department; David Ku, a Regents professor with appointments in the Georgia Tech School of Mechanical Engineering and College of Management, and Emory's Department of Surgery; and Nicholas Chronos, president of SJTRI.

The consortium will provide assistance for pediatric medical devices from academic institutions and small businesses. The three technologies that will be investigated initially are:

• A smartphone attachment designed for at-home ear examinations;
• A renal dialysis device; and
• A gel designed to delay the re-fusion of a child’s skull bones after surgery for craniosynostosis.

The first innovation is the RemOtoscope -- a smartphone attachment designed by Lam for at-home ear examinations. Ear infections result in more than 15 million doctor office visits each year in the United States because diagnosing them requires direct observation of the child's eardrum and ear canal with a device called an otoscope. Lam envisions a physician remotely guiding placement of the device and diagnosing the condition via real-time video consultation with parents at home. The smartphone capabilities will also enable the transmission of other relevant clinical information to guide the physician in making the correct diagnosis.

The second device the consortium will bring into the pipeline is a renal dialysis device designed especially for children with kidney failure. There is currently no FDA-approved continuous bedside dialysis device for children. When critically ill children need kidney dialysis, doctors are forced to adapt adult-size dialysis equipment. These adapted adult devices can withdraw too much fluid from a pediatric patient, leading to dehydration, shock and loss of blood pressure. Matthew Paden, a pediatric critical care physician at Children's Healthcare of Atlanta and Emory realized this problem and has collaborated with Ajit Yoganathan, a Georgia Tech Regents professor and the Wallace H. Coulter Distinguished Faculty Chair in Biomedical Engineering, to develop the device.

The consortium will also investigate the development of a gel designed to delay the re-fusion of a child's skull bones after surgery for craniosynostosis. Craniosynostosis affects approximately one in every 2,500 babies in the United States and is caused by the premature closure of gaps between skull bones. The gel is being developed by Boyan; Joseph Williams, clinical director of craniofacial plastic surgery at Children's Healthcare of Atlanta and clinical assistant professor in the Department of Plastic and Reconstructive Surgery at Emory University; and Coulter Department M.D./Ph.D. student Chris Hermann, senior scientist Rene Olivares-Navarrete, visiting professor Zvi Schwartz and associate professor Niren Murthy.

Future projects will be selected through the consortium's seed grant competition, which will provide awards between $25,000 and $50,000 to inventors in the partnering institutions and the business community to develop a pediatric medical device through the consortium. Entries are due Nov. 1, 2011.

Additional devices will also be identified through technology development and commercialization programs, including the Coulter Department capstone design class, the TI:GER (Technological Innovation: Generating Economic Results) program in the Georgia Tech College of Management, Georgia Tech's comprehensive center for technology commercialization called VentureLab and the Goizeuta Business School at Emory.

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Patients with PAD experience blocked arteries in the legs and feet, which can lead to leg amputation in advanced cases. Because advanced PAD in diabetes frequently affects small vessels, conventional intervention and surgical treatment are ineffective in many cases.

DN, which damages the neural vasculature and neuronal cells, is the most common complication of diabetes, affecting 60 percent of patients.

Growing evidence has shown that cells taken from a patient’s own bone marrow, called bone marrow-derived endothelial progenitor cells (EPCs), can be effective in treating various cardiovascular diseases and diabetic neuropathy by repairing blood vessels. Thus far, however, EPCs derived from diabetic patients have been only modestly effective for these autologous (self-directed) therapies.

The Emory research team, based on earlier findings, believes epigenetic changes in the EPCs of diabetic patients may be at fault. Epigenetic factors direct genes to be either expressed or silenced, but they don’t affect the underlying DNA sequence of an organism. Epigenetic alterations in the chromatin of the EPCs of diabetic patients seem to be the culprit. Chromatin is the packaging mechanism for DNA in the nucleus of cells.

“We plan to investigate epigenetic chromatin changes in diabetic EPCs, and to reprogram or re-engineer these EPCs with small molecular epigenetic regulators and biomaterial to enhance or restore their function,” Yoon explains. “Other research has shown the ability of small molecules to induce chromatin remodeling of affected genes and alter gene expression, and we believe this is a promising approach.”

The research team will use animal models to test the therapeutic effects of the reprogrammed cells for PAD and DN. The next step will be a pilot clinical trial in human patients with complications of diabetes.

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"The EFRI research teams will probe some profound aspects of the interface of biology and engineering," said Sohi Rastegar, director of EFRI. "If they are successful, the principles and theories uncovered in their investigations could unlock many technological opportunities."

This year, 14 transformative, fundamental research projects were awarded EFRI grants in two emerging areas: technologies that build on understanding of biological signaling, and machines that can interact and cooperate with humans.

The three Georgia Tech projects include:

• Developing a "therapeutic robot" to help rehabilitate and improve motor skills in people with mobility problems;
• Creating wearable sensors that allow blind people to "see" with their hands, bodies or faces;
• Generating and rigorously testing quantitative models that describe spatial and temporal regulation of cell differentiation in tissues.

The therapeutic robot could enhance, assist and improve motor skills in humans with varying motor capabilities and deficits. The goal of the project is to program a humanoid rehabilitation robot to perform a "partnered box step," which is a defined pattern of weight shifts and directional changes, solely based on interpreting movement cues from subtle changes in forces between the hands and arms of the robot and the person.

To do this, researchers at Georgia Tech and Emory University will study how humans use their muscles to walk, balance and generate force signals with the hands for guidance when moving in cooperation with another person. They will also study "rehabilitative partnered dance," which has been specifically adapted to help improve gait and balance in individuals with motor impairments.

"Our vision is to develop robots that will interact with humans as both assistants and movement therapists," explained principal investigator Lena Ting, an associate professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. "We expect our project to have a long-term impact on quality of life of individuals with movement difficulties, such as those caused by Parkinson's disease, stroke and injury by improving fitness, motor skills and social engagement."

Working with Ting on the project are Emory University School of Medicine (geriatrics) assistant professor Madeleine Hackney, Coulter Department of Biomedical Engineering assistant professor Charlie Kemp and Georgia Tech School of Interactive Computing assistant professor Karen Liu.

For the second project, researchers at Georgia Tech and The City College of New York will investigate devices for "alternative perception" and the principles underlying the human-machine interaction. Alternative perception combines electronics and the other senses to emulate vision. In addition to aiding the visually impaired, the findings are expected to have other applications, such as the development of intelligent robots.

The researchers plan to untangle how humans learn to coordinate input from their senses -- e.g. vision, touch -- with movements, like reaching for a glass or moving through a crowded room. They will then map out how machines, such as robots and computers, learn similar tasks, to model devices that can assist humans.

The team envisions a multifunctional array of sensors on the body and has already developed prototypes for some of the devices. The full complement of wearable sensors would help a sightless person navigate by conveying information about his or her surroundings.

The researchers hope their findings on perception, and the prototypes they develop, will spawn a raft of wearable electronic devices to help blind people "see" their environment at a distance through touch, hearing and other senses. The technology would also benefit sighted individuals who must navigate in poor visibility, such as firefighters and pilots.

Principal investigator Zhigang Zhu, professor of computer science and computer engineering in City College's Grove School of Engineering, will collaborate with City College professor of psychology and director of the Program in Cognitive Neuroscience Tony Ro, City College professor of electrical engineering Ying Li Tian, Georgia Tech Woodruff School of Mechanical Engineering professor Kok-Meng Lee, and Georgia Tech School of Applied Physiology associate professor Boris Prilutsky.

The third project will address a fundamental question of developmental biology: what controls the spatial and temporal patterns of cell differentiation? Answering this question will lead to a better understanding of the basic principles of embryogenesis, explain origins of developmental disorders, and provide guidelines for tissue engineering and regenerative medicine.

The research will be conducted by principal investigator and Princeton University Department of Chemical and Biological Engineering associate professor Stanislav Shvartsman, Georgia Tech School of Chemical and Biomolecular Engineering associate professor Hang Lu, New York University Department of Biology professor Christine Rushlow, and University of Illinois at Urbana Champaign Department of Computer Science associate professor Saurabh Sinha.

Scientists know that among an embryo's first major developments is the establishment of its dorsoventral axis, which runs from its back to its belly. The researchers plan to study how this axis development unfolds -- specifically the presence and location of proteins during the process, which give rise to muscle, nerve and skin tissues.

To enable large-scale quantitative analyses of protein positional information along the dorsoventral axis, Lu and Shvartsman will further develop a microfluidic device they previously designed to reliably and robustly orient several hundred embryos in just a few minutes.

"By understanding this system at a deeper, quantitative level, we will elucidate general principles underlying the operation of genetic and multicellular networks that drive development," said Lu.

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A new five-year grant of $1.6 million from the National Institutes of Health will create a training center in computational neuroscience, one of only five national training centers supported by the NIH through its NIH Blueprint training grant program.

The grant is entitled “From cells to systems and applications: computational neuroscience training at Emory and Georgia Tech.” Principal investigators are Dieter Jaeger, PhD, professor of biology, Emory University and Garrett Stanley, PhD, associate professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. 

“The NIH Blueprint training grants are particularly innovative in that they combine undergraduate and graduate training programs and provide trainee support at both levels,” says Jaeger. “This is a mission that is highly synergistic with the training mission at Emory and Georgia Tech.”

The NIH Blueprint is a framework to enhance cooperative activities among 16 NIH Institutes, Centers, and Offices that support research on the nervous system.

The core training group will initially consist of 16 faculty members from departments spanning Emory University School of Medicine (physiology, neurology, anesthesiology, biomedical engineering) and Emory College of Arts and Sciences (biology, psychology) as well as Georgia Tech (biomedical engineering, electrical engineering)

“This impressive range of faculty and departments provides testimony to the highly collaborative and interdisciplinary nature of this field of study at Georgia Tech and Emory,” notes Stanley.

The training grant funds students in the Emory Neuroscience Program and the joint Emory/Georgia Tech BME PhD program, and undergraduates on both campuses.

The National Science Foundation (NSF) has awarded the scientists a $2M research grant over four years through its Division of Emerging Frontiers in Research and Innovation. The project is called “Partnered Rehabilitative Movement: Cooperative Human-robot Interactions for Motor Assistance, Learning, and Communication.”

“Our vision is to develop robots that will interact with humans as both assistants and movement therapists,” explains principal investigator Lena Ting, PhD, associate professor in the Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. “We expect our project to have a long-term impact on quality of life of individuals with movement difficulties, such as those caused by Parkinson’s disease, stroke, and injury, by improving fitness, motor skills and social engagement.”

The robot developed through the project could enhance, assist and improve motor skills in humans with varying motor capabilities and deficits. Other applications of the technologies and theories developed could include the design of prosthetic devices or sports robots that entertain and improve fitness. The researchers also believe their work will advance understanding of how the brain controls movement and other functions. Madeleine Hackney, PhD, assistant professor of medicine (geriatrics) in Emory University School of Medicine is co-principal investigator of the project. Co-PIs at Georgia Tech are biomedical engineering assistant professor Charlie Kemp, PhD, and assistant professor of interactive computing, Karen Liu, PhD.

The scientists will begin their work by studying how humans use their muscles to walk, balance and generate force signals with the hands for guidance when moving in cooperation with another person. They will study “rehabilitative partnered dance,” which has been specifically adapted to help improve gait and balance in individuals with motor impairments. The partnered dance is based on tactile and motor cooperation between two individuals. Prior work by Hackney showed that participation in partnered rehabilitative movement improved balance and walking skills in individuals with motor deficits due to Parkinson’s disease.

The goal is to then program a humanoid rehabilitation robot to perform a “partnered box step,” which is a defined pattern of weight shifts and directional changes, solely based on interpreting movement cues from subtle changes in forces between the hands and arms of the robot and the person.

Over the course of the project, the team will test their models of human sensorimotor coordination, cooperation and communication by demonstrating the robot’s ability to participate in the box step as a leader or follower and adapt its movements to the motor skill level of a human partner.

The five-year project focuses on developing biomaterials capable of capturing certain molecules from embryonic stem cells and delivering them to wound sites to enhance tissue regeneration in adults. By applying these unique molecules, clinicians may be able to harness the regenerative power of stem cells while avoiding concerns of tumor formation and immune system compatibility associated with most stem cell transplantation approaches.

"Pre-clinical and clinical evidence strongly suggests that the biomolecules produced by stem cells significantly impact tissue regeneration independent of differentiation into functionally competent cells," said Todd McDevitt, director of the Stem Cell Engineering Center at Georgia Tech and an associate professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. "We want to find out if the signaling molecules responsible for scarless wound healing and functional tissue restoration during early stages of embryological development can be used with adult wounds to produce successful tissue regeneration without scar formation."

In addition to McDevitt, Coulter Department associate professor Johnna Temenoff and Woodruff School of Mechanical Engineering professor Robert Guldberg are also investigators on the project.

Regenerative medicine seeks to restore normal structure and function to tissues compromised by degenerative diseases and traumatic injuries. The contrast between embryonic and adult wound healing suggests that molecules that facilitate tissue regeneration during embryonic development are distinctly different from those of adult tissues.

This grant includes plans for engineering biomaterials that can efficiently capture morphogens, which are molecules secreted by embryonic stem cells undergoing differentiation. The study will also evaluate the regenerative activity of molecule-filled biomaterials in animal models of dermal wound healing, hind limb ischemia and bone fractures. Examining the effects of the morphogens on a range of animal wound models will increase the likelihood of success and define any limitations of the technology, such as its use for specific tissues or injuries.

"Biomaterials have largely been used in an attempt to direct stem cell differentiation or serve as passive cell transplantation vehicles for regenerative medicine and tissue engineering purposes," said McDevitt, who is also a Petit Faculty Fellow in the Institute for Bioengineering and Bioscience at Georgia Tech. "The idea of specifically engineering biomaterial properties to capture and deliver complex assemblies of stem cell-derived morphogens without transplanting the cells themselves represents a novel strategy to translate the potency of stem cells into a viable regenerative medicine therapy."

The award was one of 17 granted this year through the NIH Director's Transformative Research Projects Program (T-R01), which was created to challenge the status quo with innovative ideas that have the potential to advance fields and speed the translation of research into improved health for the American public.

Another T-R01 grant was awarded to Coulter Department professor Shuming Nie, associate professor May Wang and University of Pennsylvania School of Medicine Thoracic Surgery Research Laboratory director Sunil Singhal. That $7 million, five-year grant will support continuing work by the Emory-Georgia Tech Nanotechnology Center for Personalized and Predictive Oncology team on developing fluorescent nanoparticle probes that hone in on cancer cells and on creating instruments that visualize them for cancer detection during surgery.

Since its inception in 2009, the NIH Director's Award Program has funded a total of 406 high-risk research projects, including 79 T-R01 awards.

"The NIH Director's Award programs reinvigorate the biomedical work force by providing unique opportunities to conduct research that is neither incremental nor conventional," said James M. Anderson, director of the Division of Program Coordination, Planning and Strategic Initiatives, who guides the NIH Common Fund's High-Risk Research program. "The awards are intended to catalyze giant leaps forward for any area of biomedical research, allowing investigators to go in entirely new directions."

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All species of life are able to develop in different ways by varying the genes they express, ultimately becoming different shapes, sizes, colors and sexes. This plasticity permits organisms to operate successfully in their environments. A new study of the genomes of social insects provides insight into the evolution of the genes involved in this developmental plasticity.

The study, which was conducted by researchers at the Georgia Institute of Technology and the University of Lausanne in Switzerland, showed that genes involved in creating different sexes, life stages and castes of fire ants and honeybees evolved more rapidly than genes not involved in these developmental processes. The researchers also found that these fast-evolving genes exhibited elevated rates of evolution even before they were recruited to produce diverse forms of an organism.

"This was a totally unexpected finding because most theory suggested that genes involved in producing diverse forms of an organism would evolve rapidly specifically because they generated developmental differences," said Michael Goodisman, an associate professor in the School of Biology at Georgia Tech. "Instead, this study suggests that fast-evolving genes are actually predisposed to generating new developmental forms."

The results of the study will be published in the Sept. 20, 2011 issue of the journal Proceedings of the National Academy of Sciences. This research was supported by the National Science Foundation.

The project was an international collaboration between Goodisman, associate professor Soojin Yi and postdoctoral fellow Brendan Hunt from the Georgia Tech School of Biology, and professor Laurent Keller, research scientist DeWayne Shoemaker, and postdoctoral fellows Lino Ometto and Yannick Wurm from the Department of Ecology and Evolution at the University of Lausanne.

Social insects exhibit a sophisticated social structure in which queens reproduce and workers engage in tasks related to brood-rearing and colony defense. By investigating the evolution of genes associated with castes, sexes and developmental stages of the invasive fire ant Solenopsis invicta, the researchers explored how social insects produce such a diversity of form and function from genetically similar individuals.

"Social insects provided the perfect test subjects because they can develop into such dramatically different forms," said Goodisman.

Microarray analyses revealed that many fire ant genes were regulated differently depending on whether the fire ant was male or female, queen or worker, and pupal or adult. These differentially expressed genes exhibited elevated rates of evolution, as predicted. In addition, genes that were differentially expressed in multiple contexts -- castes, sexes or developmental stages -- tended to evolve more rapidly than genes that were differentially expressed in only a single context.

To examine when the genes with elevated rates of evolution began to evolve rapidly, the researchers compared the rate of evolution of genes associated with the production of castes in the fire ant with the same genes in a wasp that does not have a caste system. They found that the genes were rapidly evolving in the genomes of both species, even though only one produced a caste system. These results were also replicated for the honeybee Apis mellifera.

"This is one the most comprehensive studies of the evolution of genes involved in producing developmental differences," Goodisman noted.

This study helps explain the fundamental evolutionary processes that allow organisms to develop different adaptive forms. Future research will include determining what these fast-evolving genes do and how they're involved in the production of different sexes, life stages and castes, said Goodisman.

This project is supported by the National Science Foundation (NSF) (Award No. DEB-0640690). The content is solely the responsibility of the principal investigators and does not necessarily represent the official views of the NSF.

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Theregenerative power of tissues and organs declines as we age. The modern daystem cell hypothesis of aging suggests that living organisms are as old as are itstissue specific or adult stem cells. Therefore, an understanding of themolecules and processes that enable human adult stem cells to initiateself-renewal and to divide, proliferate and then differentiate in order torejuvenate damaged tissue might be the key to regenerative medicine and an eventualcure for many age-related diseases. A research groupled by the Buck Institute for Research on Aging in collaboration with the Georgia Institute of Technology, conducted the study thatpinpoints what is going wrong with the biological clock underlying the limited division ofhuman adult stem cells as they age.

“Wedemonstrated that we were able to reverse the process of aging for human adultstem cells by intervening with the activity of non-protein coding RNAs originated fromgenomic regions once dismissed as non-functional  ‘genomic junk’,” said Victoria Lunyak, associate professor at the Buck Institutefor Research on Aging.

Adultstem cells are important because they help keep human tissues healthy byreplacing cells that have gotten old or damaged. They’re also multipotent,which means that an adult stem cell can grow and replace any number of bodycells in the tissue or organ they belong to. However, just as the cells inthe liver, or any otherorgan, can get damaged over time, adult stem cells undergo age-related damage. And when this happens, the bodycan’t replace damaged tissue as well as it once could, leading to a host of diseasesand conditions. But if scientists can find a way to keep these adult stem cellsyoung, they could possibly use these cells to repair damaged heart tissue aftera heart attack; heal wounds; correct metabolic syndromes; produce insulin forpatients with type 1 diabetes; cure arthritis and osteoporosis and regeneratebone.

Theteam began by hypothesizing that DNA damage in the genome of adult stem cells wouldlook very different from age-related damage occurring in regular body cells. They thoughtso because body cells are known to experience a shortening of the caps found atthe ends of chromosomes, known as telomeres. But adult stem cells are known tomaintain their telomeres. Much of the damage in aging is widely thought to be aresult of losing telomeres. So there must be different mechanismsat play that arekey to explaining how aging occurs in these adult stem cells, they thought.

Researchersused adult stem cells from humans and combined experimental techniques withcomputational approaches to study the changes in the genome associated withaging.  They compared freshly isolated human adult stem cells from young individuals, which canself-renew, to cellsfrom the same individuals that were subjected to prolonged passaging inculture. This accelerated model of adult stem cell aging exhausts the regenerativecapacity of the adult stem cells. Researchers looked at the changes in genomic sites that accumulateDNA damage in both groups.

“Wefound the majority of DNA damage and associated chromatin changes that occurredwith adult stem cell aging were due to parts of the genome known as retrotransposons,”said King Jordan, associate professor in the School of Biology at Georgia Tech.

“Retroransposonswere previously thought to be non-functional and were even labeled as ‘junk DNA’, but accumulating evidenceindicates these elements play an important role in genome regulation,” headded.

Whilethe young adult stem cells were able to suppress transcriptional activity ofthese genomic elements and deal with the damage to the DNA, older adult stem cells werenot able to scavenge this transcription. New discovery suggests that this event is deleteriousfor the regenerativeability of stem cells and triggers a process known as cellular senescence.

“Bysuppressing the accumulation of toxic transcripts from retrotransposons, wewere able to reverse the process of human adult stem cell aging in culture,”said Lunyak.

“Furthermore,by rewinding the cellular clock in this way, we were not only able torejuvenate ’aged’ human stem cells, but to our surprise we were able to resetthem to an earlier developmental stage, by up-regulating the “pluripotency factors” – the proteinsthat are critically involved in the self-renewal of undifferentiated embryonicstem cells.” she said.

Nextthe team plans to use further analysis to validate the extent to which therejuvenated stem cells may be suitable for clinical tissue regenerativeapplications.

Thestudy was conducted by a team with members from the Buck Institute for Researchon Aging, the Georgia Institute of Technology, the University of California,San Diego, Howard Hughes Medical Institute, Memorial Sloan-Kettering CancerCenter, International Computer Science Institute, Applied Biosystems andTel-Aviv University.

Citation:
Inhibitionof activated pericentromeric SINE/Alu repeat transcription in senescent human
adult stem cells reinstates self-renewal.  Cell Cycle, Volume 10, Issue 17, September 1, 2011

Written byDavid Terraso, Georgia Tech/Kris Rebillot, Buck Institute

Beginning October 10, 2011, IBB will begin accepting research project submissions from graduate student and/or postdocs to be considered to serve as mentors to the incoming class of Petit Scholars. 

The application submission deadline for the 2012 Petit Scholars is Friday, October 7, 2011 at 5:00pm. For complete program requirements and online application, visit:  2012 Petit Scholars 

Researchers in the Atlanta-based Center for Pediatric Healthcare Technology Innovation are developing imaging techniques designed to predict whether a child's skull bones are likely to grow back together too quickly after surgery. They are also developing technologies that may delay a repeat of the premature fusion process.

"Babies are usually only a few months old during the first operation, which lasts more than three hours and requires a unit of blood and a stay in the intensive care unit, so our goal is to develop technologies that will simplify the initial surgery and limit affected babies to this one operation," said center co-director Joseph Williams, clinical director of craniofacial plastic surgery at Children's Healthcare of Atlanta at Scottish Rite and clinical assistant professor in the Department of Plastic and Reconstructive Surgery at Emory University.

Craniosynostosis affects approximately one in every 2,500 babies in the United States. The condition is caused by the premature closure of sutures with bone. Sutures, which are made of tissue that is more flexible than bone, play an important role in brain growth by providing a method for the skull to increase in size. If the sutures close too soon and get replaced with bony tissue, the skull may limit the normal expansion of the brain.

If untreated, craniosynostosis can cause a range of developmental problems. If treated using the standard treatment course, surgeons remove the fused skull bones, break them up, reposition them, and hold them in place with plates and screws. This usually slows bone growth between the bone pieces, allowing room for expansion of the brain. However, studies show that more than six percent of babies need a second operation to separate the bones again and 25 percent of those require a third operation.

"Following the first surgery, there's a clinical need to be able to screen children on a regular basis to predict when their skull bones are going to fuse together again so that the surgeons can determine if additional intervention will be required," said center director Barbara Boyan, the Price Gilbert, Jr. Chair in Tissue Engineering in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University and associate dean for research and innovation in the Georgia Tech College of Engineering.

To address this need, the researchers have developed a non-invasive technique to monitor bone growth with computed tomography images. They created software that identifies bone in the images, quantifies the distance between the bones, the mass of bone in the gap, and the area and volume of the gap. The research team has demonstrated the utility of this "snake" algorithm using a mouse model of cranial development and recently presented their findings at the 2011 Plastic Surgery Education Foundation conference.

"Using our snake algorithm to analyze computed tomography images of developing skulls in mice, we were able to monitor different types and speeds of bone growth on a daily basis for many weeks," said Chris Hermann, an M.D./Ph.D. student in the Coulter Department. "While one suture fused between 12 and 20 days and then significantly increased in mass for the next 20 days, another came closer together and increased in mass but remained largely open."

The research team recently adapted the technology for use in children and began a clinical study to determine the effectiveness of the algorithm to diagnose cases of craniosynostosis. The researchers hope this technology will improve the ability of physicians to diagnose and determine the severity of craniosynostosis.

In addition, the researchers are studying the biological basis of the condition and developing technologies they hope will delay bone growth and eliminate the need for additional operations. In one project, Coulter Department research scientist Rene Olivares-Navarrete and Williams are examining individuals with craniosynostosis to identify genes that influence suture fusion. Determining the genes that control suture closure may help the researchers identify potential therapeutic targets to prevent premature suture fusion.

The research team has also designed a gel to be injected into the gap created between skull bones during the first surgery. The material -- called a hydrogel because it contains a significant amount of water -- would deliver specific proteins to the area to delay, but not prevent, bone growth.

"The hydrogel cross-links spontaneously because of a reaction between a polyethylene-glycol monomer and a cross-linking molecule, allowing for polymerization without the use of chemical initiators or the production of free radicals," explained Hermann.

Preliminary results in a mouse model of cranial development indicate that the gel, developed in collaboration with Coulter Department associate professor Niren Murthy, can be injected into a gap between skull bones, firm up rapidly and not injure underlying soft tissues or impair bone healing. These pre-clinical results were presented at the Society for Biomaterials Annual Meeting in April 2011.

Both Boyan and Williams see promise in using these technologies to improve the treatment of children with craniosynostosis and eliminate additional operations sometimes needed to treat the condition.

"During the initial surgery, injecting the gel may reduce the operation's severity if it eliminates the need for plates and screws to hold the skull bones in place afterward," explained Boyan, who is also a Georgia Research Alliance (GRA) Eminent Scholar. "After the surgery, if the computed tomography images tell us that the skull is closing too quickly, we may be able to inject the gel through the skin overlying the skull without surgery to further delay the bones from fusing."

The researchers are currently improving the protein release kinetics of the hydrogel and conducting pre-clinical experiments to determine which proteins successfully delay bone growth when included in the gel. Approval from the Food and Drug Administration will be required before this system and hydrogel can be used as a treatment for craniosynostosis.

The Center for Pediatric Healthcare Technology Innovation is supported by Children's Healthcare of Atlanta, in collaboration with Georgia Tech.

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The seed grant recipients address a wide range oftopics including profiling  singlecells to understand the heterogeneity of different cell types and newapproaches to traumatic brain injury.  Thecall for proposals was welcomed by teams of Petit Institute faculty with onefaculty member from Georgia Tech’s College of Science and one from the Collegeof Engineering. 

“This new program aims to promote the collaborationof new teams of researchers and help them establish preliminary results toapply for large external grant proposals,” said Robert Guldberg, PhD, directorof the Petit Institute.  “This initiativeis directly in-line with the Petit Institute’s mission, funding cutting-edgeresearch at the interface of bioengineering and the biosciences.”

MelissaKemp, assistant professor in the Wallace H. Coulter Department for BiomedicalEngineering and Greg Gibson, professor in the School of Biology, proposed aproject which aims to develop the measurement tools for relating variability in both genomicand protein information at the single cell level. The ability to conduct this type ofprofiling in single cells represents a remarkable technological advance in thelast two years.

“Studies ofgenomic data often fail to bridge the observed variation in DNA sequences tocellular function, in part due to the variation that is present by both typesof measurement,” Kemp said, “with the technologies this project is developing,we will be able to compare population-averaged data to single cell measurementsin order to gain new insight in relating genes to phenotype.” 

MichelleLaPlaca, associate professor in the Wallace H. Coulter Department of BiomedicalEngineering and Al Merrill, professor in the School of Biology, are partneringto merge traumatic brain injury with lipid biology in the hopes of evaluating, for thefirst time, plasma membrane breakdown mechanisms and lipid signaling followingtraumatic brain injury. 

“Traumatic brain injury remains a major clinical problem with few effectivetreatments and the devastating sequelae following this type of injury leads tochronic neural deficits,” LaPlaca stated. “We are optimistic that these fundswill propel this important research forward.”

Fundingfor the new seed grants comes chiefly from Petit Institute's endowment as well as contributionsfrom the College of Science and College of Engineering.  Each team will receive $50,000 a year for twoyears, however, the second year of funding will be contingent on submission ofan external collaborative grant proposal by July 2012.

The three new Regents’ Professors at Georgia Tech are Mark Prausnitz, professor and director of the Center for Drug Design, Development and Delivery in the School of Chemical & Biomolecular Engineering; Seth Marder, professor in the School of Chemistry and Biochemistry and founding director of the Center for Organic Photonics and Electronics in the colleges of Engineering and Sciences; and Gary Schuster, Vasser Woolley Professor in the School of Chemistry and Biochemistry.

Two Regents’ Researchers appointed include Gisele Bennett, professor and director of the Electro-Optical Systems Laboratory in the Georgia Tech Research Institute; and Suzanne Eskin, principal research scientist in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.

“We are immensely proud of our new Georgia Tech Regents’ Professors and Researchers,” said G. P. “Bud” Peterson, Georgia Tech’s president.  “They are conducting breakthrough research that is gaining national attention.  The fact that we have five Georgia Tech faculty members receiving this honor from the Board of Regents in one year is a reflection of the caliber of scholars we have at Tech.”

A Regents' Professorship and Regents’ Researcher title represents the highest academic status bestowed by the University System of Georgia. It is meant to recognize a substantial, significant and ongoing record of scholarly achievement that has earned high national esteem over a sustained period. 

Prausnitz has received international acclaim for his research on biophysical methods of drug delivery, which employ microneedles, ultrasound, lasers, electric fields, heat, convective forces and other physical means to control the transport of drugs, proteins, genes and vaccines into and within the body.

Marder is working on bringing nanotechnology out of the lab and into the marketplace. Using a process known as two-photon absorption, the research groups of Marder and colleague Joseph Perry are developing a broad set of materials for 3D micro- and nanolithography.

Schuster is a nationally known scholar and researcher with an extensive list of published articles on topics ranging from biochemistry through physical chemistry, as well as a number of scientific discoveries with commercial applications. He also held top leadership roles at Georgia Tech such as interim president, provost and dean of the College of Sciences.

Bennett has been praised for the programs she has built around automatic identification technologies using radio frequency identification and container security. Her research activities include the study of optical coherence imaging systems.

Eskin has contributed to research on vascular biology, cardiovascular tissue engineering and gene expression of vascular cells. She studies the comparative effects of mechanical forces accompanying blood flow and pressure on the blood vessel wall.

The titles are awarded by the Board of Regents, which governs the University System of Georgia, upon the unanimous recommendation of the president, the chief academic officer, the appropriate academic dean and three other faculty members named by the president, and upon the approval of the chancellor and the committee on academic affairs.

An estimated 1.6 million Americans suffer moderate to severe leakage through their tricuspid valve, a complex structure that closes off the heart's right ventricle from the right atrium. Most people have at least some leakage in the valve, but what causes the problem is not well understood.

A new study, published online in the journal Circulation on August 1, 2011, found that either dilating the tricuspid valve opening or displacing the papillary muscles that control its operation can cause the valve to leak. A combination of the two actions can increase the severity of the leakage, which is called tricuspid regurgitation.

"We think this is the first in vitro investigation into the mechanics of the tricuspid valve, and that our findings into the mechanisms that cause tricuspid regurgitation could lead to improved diagnosis and treatment," said Ajit Yoganathan, Regents professor and Wallace H. Coulter Distinguished Faculty Chair in Biomedical Engineering in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.

The tricuspid valve consists of three flaps that open to allow blood to flow from the heart's upper right chamber to the ventricle. To close the valve, the flaps re-cover the opening, keeping blood from flowing back into the chamber it just left. When the valve is leaky or doesn't close tightly enough, blood flows backward into the chamber just after the heart contracts.

Tricuspid regurgitation has been increasingly recognized as a source of disease in patients with chronic mitral valve regurgitation, but surgical repair of the tricuspid valve alone is recommended only in rare cases. If an individual suffers from severe tricuspid regurgitation, surgeons will sometimes repair the tricuspid valve during a surgery to repair other leaky heart valves.

"Standard clinical procedures that detail when and how tricuspid valve repairs should be performed need to be developed and this study suggests several items that should be considered," said one of the study’s co-authors David H. Adams, chair of the Department of Cardiothoracic Surgery at Mount Sinai Medical Center in New York City. "Current repairs for tricuspid regurgitation focus mainly on remodeling the valve's opening to correct enlargement, but this study shows that it may also be important to restore the position of the papillary muscles, providing as much overlap as possible, in order to conduct effective and durable tricuspid valve repairs."

With funding from the American Heart Association, Yoganathan and Coulter Department graduate student Erin Spinner conducted experiments with porcine tricuspid valves to determine possible causes of tricuspid regurgitation. The valves were attached to a plate designed to create physiological dilation and then placed inside a right heart simulator.

The researchers first investigated the effect of dilating the opening of the tricuspid valves. When the openings stretched to an area 40 percent larger than their normal size, a hole appeared in the central region of the valve. The hole caused leakage, and increased in size with further dilatation. This finding surprised the researchers because similar studies using the same method had shown that the heart's mitral valve could withstand dilation of 75 percent before leaking.

"These results tell us that the tricuspid valve is a much more complex valve than the mitral valve, which only has two flaps," explained Spinner. "Forming a proper seal over the valve opening might be more difficult with three flaps, which could be why such a large percentage of the population experiences some level of tricuspid regurgitation and why some individuals with annular dilation have tricuspid regurgitation and others do not."

The research team also investigated the effect of displacing the valve's three papillary muscles, which attach to the valve via threads. Contraction of the papillary muscles opens the valve and relaxation of the muscles closes the valve. The study showed that papillary displacement alone resulted in significant tricuspid leakage.

"While isolated displacement of the papillary muscles is rare, these results are relevant toward understanding what may happen if the size of the valve opening is repaired, but the papillary muscles are left displaced," noted Yoganathan.

The study also showed that higher levels of tricuspid leakage resulted when the researchers combined the conditions -- dilation of 40 percent or greater and displacement of all papillary muscles.

In their future work, the Coulter Department researchers plan to look at the effect of pulmonary hypertension on the tricuspid valve, because tricuspid regurgitation usually develops in association with pulmonary hypertension -- which is abnormally high blood pressure in the lungs. They also plan to work with their clinical collaborators to extend their findings to humans.

"In our in vitro study we were able to select specific porcine valves, but with human subjects there will be more anatomical variety. For example, two people may have valves of the same diameter, but one person may have longer flaps that are able to compensate for dilation whereas the other might not," noted Yoganathan.

In addition to those already mentioned, Pedro del Nido, a professor in the Department of Cardiothoracic Surgery at Children's Hospital Boston; Emir Veledar, an assistant professor with a joint appointment in the Division of Cardiology and Division of Epidemiology at Emory University; and Coulter Department research engineer Jorge Jimenez and undergraduate students Patrick Shannon and Dana Buice also contributed to this work.

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Scientistshave studied a yeast protein called Lsb2 that can promote spontaneous prionformation. This unstable, short-lived protein is strongly induced by cellularstresses such as heat. Lsb2’s properties also illustrate how cells havedeveloped ways to control and regulate prion formation. The results arepublished in the July 22 issue of the journal Molecular Cell.

Thestudy was conducted by members of the Center for Nanobiology of the MacromolecularAssembly Disorders (NanoMAD) which is made up of scientists from the GeorgiaInstitute of Technology and Emory University. Scientists from the NationalInstitues of Health and the University of Illinois at Chicago also contributedto the study. The first author is senior associate Tatiana Chernova, PhD atEmory.

Theaggregated, or amyloid, forms of proteins connected with several otherneurodegenerative diseases such as Alzheimer’s, Parkinson’s and Huntington’scan, in some circumstances, act like prions. So the findings provide insightinto how the ways that cells deal with stress might lead to poisonous proteinaggregation in human diseases.

“Adirect human homolog of Lsb2 doesn’t exist, but there may be a protein thatperforms the same function,” said Keith Wilkinson, professor of biochemistry atEmory University School of Medicine. “The mechanism may say more about othertypes of protein aggregates than about classical prions in humans. Thismechanism of seeding and growth may be more important for aggregate formationin diseases such as Huntington’s.”

Lsb2does not appear to form stable prions by itself. Rather, it seems to bind toand encourage the aggregation of another protein, Sup35, which does formprions.

“Ourmodel is that stress induces high levels of Lsb2, which allows the accumulationof misfolded prion proteins,” Wilkinson said. “Lsb2 protects enough of thesenewborn prion particles from the quality control machinery for a few of them toget out.”

Incontinuation of previous research by Yury Chernoff, director of NanoMAD andprofessor in the School of Biology at Georgia Tech, the new data also show thatin addition to promoting new prions, Lsb2 strengthens existing prions duringstress.

"Littleis known about physiological and environmental conditions influencing amyloiddiseases in humans," said Chernoff. "Therefore, prophylacticmeasures, which could end up being more effective than therapies, areessentially non-existant. We hope that yeast model will help to fill thisgap."

Theresearch was supported by the National Institutes of Health.

Writtenby: Emory University and the Georgia Institute of Technology

The technique, which uses a heated atomic force microscope (AFM) tip to produce patterns, could facilitate high-density, low-cost production of complex ferroelectric structures for energy harvesting arrays, sensors and actuators in nano-electromechanical systems (NEMS) and micro-electromechanical systems (MEMS). The research was reported July 15 in the journal Advanced Materials.

"We can directly create piezoelectric materials of the shape we want, where we want them, on flexible substrates for use in energy harvesting and other applications," said Nazanin Bassiri-Gharb, co-author of the paper and an assistant professor in the School of Mechanical Engineering at the Georgia Institute of Technology. "This is the first time that structures like these have been directly grown with a CMOS-compatible process at such a small resolution. Not only have we been able to grow these ferroelectric structures at low substrate temperatures, but we have also been able to pattern them at very small scales."

The research was sponsored by the National Science Foundation and the U.S. Department of Energy. In addition to the Georgia Tech researchers, the work also involved scientists from the University of Illinois Urbana-Champaign and the University of Nebraska Lincoln.

The researchers have produced wires approximately 30 nanometers wide and spheres with diameters of approximately 10 nanometers using the patterning technique. Spheres with potential application as ferroelectric memory were fabricated at densities exceeding 200 gigabytes per square inch -- currently the record for this perovskite-type ferroelectric material, said Suenne Kim, the paper's first author and a postdoctoral fellow in laboratory of Professor Elisa Riedo in Georgia Tech's School of Physics.

Ferroelectric materials are attractive because they exhibit charge-generating piezoelectric responses an order of magnitude larger than those of materials such as aluminum nitride or zinc oxide. The polarization of the materials can be easily and rapidly changed, giving them potential application as random access memory elements.

But the materials can be difficult to fabricate, requiring temperatures greater than 600 degrees Celsius for crystallization. Chemical etching techniques produce grain sizes as large as the nanoscale features researchers would like to produce, while physical etching processes damage the structures and reduce their attractive properties. Until now, these challenges required that ferroelectric structures be grown on a single-crystal substrate compatible with high temperatures, then transferred to a flexible substrate for use in energy-harvesting.

The thermochemical nanolithography process, which was developed at Georgia Tech in 2007, addresses those challenges by using extremely localized heating to form structures only where the resistively-heated AFM tip contacts a precursor material. A computer controls the AFM writing, allowing the researchers to create patterns of crystallized material where desired. To create energy-harvesting structures, for example, lines corresponding to ferroelectric nanowires can be drawn along the direction in which strain would be applied.

"The heat from the AFM tip crystallizes the amorphous precursor to make the structure," Bassiri-Gharb explained. "The patterns are formed only where the crystallization occurs."

To begin the fabrication, the sol-gel precursor material is first applied to a substrate with a standard spin-coating method, then briefly heated to approximately 250 degrees Celsius to drive off the organic solvents. The researchers have used polyimide, glass and silicon substrates, but in principle, any material able to withstand the 250-degree heating step could be used. Structures have been made from Pb(ZrTi)O3 -- known as PZT, and PbTiO3 -- known as PTO.

"We still heat the precursor at the temperatures required to crystallize the structure, but the heating is so localized that it does not affect the substrate," explained Riedo, a co-author of the paper and an associate professor in the Georgia Tech School of Physics.

The heated AFM tips were provided by William King, a professor in the Department of Mechanical Science and Engineering at the University of Illinois at Urbana-Champaign.

As a next step, the researchers plan to use arrays of AFM tips to produce larger patterned areas, and improve the heated AFM tips to operate for longer periods of time. The researchers also hope to understand the basic science behind ferroelectric materials, including properties at the nanoscale.

"We need to look at the growth thermodynamics of these ferroelectric materials," said Bassiri-Gharb. "We also need to see how the properties change when you move from the bulk to the micron scale and then to the nanometer scale. We need to understand what really happens to the extrinsic and intrinsic responses of the materials at these small scales."

Ultimately, arrays of AFM tips under computer control could produce complete devices, providing an alternative to current fabrication techniques.

"Thermochemical nanolithography is a very powerful nanofabrication technique that, through heating, is like a nanoscale pen that can create nanostructures useful in a variety of applications, including protein arrays, DNA arrays, and graphene-like nanowires," Riedo explained. "We are really addressing the problem caused by the existing limitations of photolithography at these size scales. We can envision creating a full device based on the same fabrication technique without the requirements of costly clean rooms and vacuum-based equipment. We are moving toward a process in which multiple steps are done using the same tool to pattern at the small scale."

In addition to those already mentioned, the research team included Yaser Bastani from the G.W. Woodruff School of Mechanical Engineering at Georgia Tech, Seth Marder and Kenneth Sandhage, both from Georgia Tech's School of Chemistry and Biochemistry and School of Materials Science and Engineering, and Alexei Gruverman and Haidong Lu from the Department of Physics and Astronomy at the University of Nebraska-Lincoln.

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"These contrast agents fill the need for probes that can accurately image small numbers of bacteria in vivo and distinguish infections from other pathologies like cancer," said Niren Murthy, an associate professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. "These probes could ultimately improve the diagnosis and treatment of bacterial infections, which remains a major challenge in medicine."

The imaging probes were described in the July 17, 2011 advance online edition of the journal Nature Materials. The research was sponsored by the National Science Foundation and National Institutes of Health.

Coulter Department postdoctoral fellows Xinghai Ning and Seungjun Lee led the project. University of Georgia Complex Carbohydrate Research Center postdoctoral associate Zhirui Wang; and Georgia State University Department of Biology associate professor Eric Gilbert and student Bryan Subblefield also contributed to the work.

In the United States in 2010, bacterial infections caused 40,000 deaths from sepsis and were the leading cause of limb amputations. A major limitation preventing the effective treatment of bacterial infections is an inability to detect them inside the body with accuracy and sensitivity. To image bacterial infections, probes must first deliver a large quantity of the contrast agent into bacteria.

"Most existing imaging probes target the bacterial cell wall and cannot access the inside of the bacteria, but maltodextrin-based imaging probes target a bacterial ingestion pathway, which allows the contrast agent to reach a high concentration within bacteria," said Murthy.

Maltodextrin-based imaging probes consist of a fluorescent dye linked to maltohexaose, which is a major source of glucose for bacteria. The probes deliver the contrast agent into bacteria through the organism's maltodextrin transporter, which only exists in bacterial cells and not mammalian cells.

"To our knowledge, this represents the first demonstration of a targeting strategy that can deliver millimolar concentrations of an imaging probe within bacteria," noted Murthy.

In experiments using a rat model, the researchers found that the contrast agent accumulated in bacteria-infected tissues, but was efficiently cleared from uninfected tissues. They saw a 42-fold increase in fluorescence intensity between bacterial infected and uninfected tissues. However, the contrast agent did not accumulate in the healthy bacterial microflora located in the intestines. Because systemically administered glucose molecules cannot access the interior of the intestines, the bacteria located there never came into contact with the probe.

They also found that the probes could detect as few as one million viable bacteria cells. Current contrast agents for imaging bacteria require at least 100 million bacteria, according to the researchers.

In another experiment, the researchers found that the maltodextrin-based probes could distinguish between bacterial infections and inflammation with high specificity. Tissues infected with E. coli bacteria exhibited a 17-fold increase in fluorescence intensity when compared with inflamed tissues that were not infected.

Additional laboratory experiments showed that the probes could deliver large quantities of imaging probes to gram-positive and gram-negative bacteria for internalization. Both types of bacteria internalized the maltodextrin-based probes at a rate three orders of magnitude faster than mammalian cells.

"Maltodextrin-based probes show promise for imaging infections in a wide range of tissues, with an ability to detect bacteria in vivo with a sensitivity two orders of magnitude higher than previously reported," said Murthy.

This project is supported by the National Science Foundation (NSF) (NSF Career Award No. BES-0546962) and the National Institutes of Health (NIH) (Award Nos. RO1 HL096796-01 and HHSN268201000043C). The content is solely the responsibility of the principal investigator and does not necessarily represent the official views of the NSF or NIH.

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Mice given a single H1N1 vaccine through the skin using a coated metal microneedle patch as well as mice vaccinated through subcutaneous injection were 100 percent protected against a lethal flu virus challenge six weeks after vaccination. However, when challenged with the H1N1 virus six months later, the injected mice had a 60 percent decrease in antibody production against the virus and extensive lung inflammation. Mice that were vaccinated with microneedles, on the other hand, maintained high levels of protection and antibody production after six months, with no signs of lung inflammation.

"A major goal of influenza vaccine development has been to confer strong immune responses, including immunological memory and cellular immune responses for long-term protection, and to limit virus spread after infection," said first author Dimitrios Koutsonanos, MD, post-doctoral fellow of microbiology and immunology at Emory University School of Medicine.

The research team also included Ioanna Skountzou, MD, PhD, Richard Compans, PhD, Maria del Pilar Martin, PhD, and Joshy Jacob, PhD, from Emory, and Georgia Tech bioengineers Mark Prausnitz, PhD, and Vladimir Zarnitsyn, PhD.

Researchers already have found that intramuscular injection is not the most efficient way to deliver vaccines. The muscles have a low concentration of cells needed to relay immune signals and activate a T-cell response, including dendritic cells, macrophages, and MHC class II-expressing cells. The skin, however, contains a rich network of antigen-presenting cells, including macrophages, Langerhans cells and dermal dendritic cells that activate cytokines and chemokines – immune signaling cells responsible for initiating an immune response.

The Emory/Georgia Tech research team previously reported that delivery of seasonal influenza vaccine through the skin using antigen-coated metal microneedle patches or dissolving microneedles elicited strong immune responses that can confer protection at least equal to conventional intramuscular injections. The team has developed dissolving microneedle technology that could be used in easy-to-administer, painless patches.

"The pandemic H1N1 A/California/04/09 influenza virus continues to be the predominant strain," said lead researcher Ioanna Skountzou, MD, PhD, assistant professor of microbiology and immunology at Emory University School of Medicine. "Our research shows that skin-based vaccination, made possible through microneedle technology, may now be a viable and more effective alternative to intramuscular injection for H1N1 flu and other strains as well."

"Microneedle delivery also offers other logistical advantages that make this method attractive for influenza vaccination, such as inexpensive manufacturing, small size for easy storage and distribution, and simple administration that might enable self-vaccination to increase patient coverage," said Prausnitz.

This news release was written by Emory University.

Media Contacts: Holly Korschun, Emory University (404-727-3990)(hkorsch@emory.edu) or John Toon (404-894-6986)(jtoon@gatech.edu).

The capsule's structure -- hollow except for polymer chains tethered to the interior of the shell -- provides spatially-segregated compartments that make it a good candidate for multi-drug encapsulation and release strategies. The microcapsule could be used to simultaneously deliver distinct drugs by filling the core of the capsule with hydrophilic drugs and trapping hydrophobic drugs within nanoparticles assembled from the polymer chains.

"We have demonstrated that we can make a fairly complex multi-component delivery vehicle using a relatively straightforward and scalable synthesis," said L. Andrew Lyon, a professor in the School of Chemistry and Biochemistry at Georgia Tech. "Additional research will need to be conducted to determine how they would best be loaded, delivered and triggered to release the drugs."

Details of the microcapsule synthesis procedure were published online on July 5, 2011 in the journal Macromolecular Rapid Communications.

Lyon and Xiaobo Hu, a former visiting scholar at Georgia Tech, created the microcapsules. As a graduate student at the Research Institute of Materials Science at the South China University of Technology, Hu is co-advised by Lyon and Zhen Tong of the South China University of Technology. Funding for this research was provided to Hu by the China Scholarship Council.

The researchers began the two-step, one-pot synthesis procedure by forming core particles from a temperature-sensitive polymer called poly(N-isopropylacrylamide). To create a dissolvable core, they formed polymer chains from the particles without a cross-linking agent. This resulted in an aggregated collection of polymer chains with temperature-dependent stability.

"The polymer comprising the core particles is known for undergoing chain transfer reactions that add cross-linking points without the presence of a cross-linking agent, so we initiated the polymerization using a redox method with ammonium persulfate and N,N,N’,N’-tetramethylethylenediamine. This ensured those side chain transfer reactions did not occur, which allowed us to create a truly dissolvable core," explained Lyon.

For the second step in the procedure, Lyon and Hu added a cross-linking agent to a polymer called poly(N-isopropylmethacrylamide) to create a shell around the aggregated polymer chains. The researchers conducted this step under conditions that would allow any core-associated polymer chains that interacted with the shell during synthesis to undergo chain transfer and become grafted to the interior of the shell.

Cooling the microcapsule exploited the temperature sensitivities of the polymers. The shell swelled with water and expanded to its stable size, while the free-floating polymer chains in the center of the capsule diffused out of the core, leaving behind an empty space. Any chains that stuck to the shell during its synthesis remained. Because the chains control the interaction between the particles they store and their surroundings, the tethered chains can act as hydrophobic drug carriers.

Compared to delivering a single drug, co-delivery of multiple drugs has several potential advantages, including synergistic effects, suppressed drug resistance and the ability to tune the relative dosage of various drugs. The future optimization of these microcapsules may allow simultaneous delivery of distinct classes of drugs for the treatment of diseases like cancer, which is often treated using combination chemotherapy.

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Vasculata^® is a summer course/workshop that promotesthe study of vascular biology.  It is designed to present an overview ofthe field and future areas of active research.  Individuals with little orno background in vascular biology are encouraged to attend, and current traineesin the field and all interested individuals are invited to participate. This includes students (undergraduates, graduate students, medical students),trainees (postdocs, research fellows, residents) and others (junior and seniorfaculty).

This meeting builds upon the legacy of research training provided byprevious Vasculata conferences by leveraging the superb critical mass ofvascular biology investigators at the three partner institutions in Atlanta.The Vasculata 2011 conference will be a distinctive addition that willincorporate several new programmatic elements to enrich the training experienceand develop a special thematic emphasis on preparing a new generation ofvascular biologists to extend the frontiers of discovery science as well as engagein translational science that bridges from ‘bench-to-bedside.” The proposedmeeting builds upon the complementary strengths of the tri-institutionalpartnership such that the program reflects the inter-disciplinary nature ofvascular biology. The conference will capture the breadth of the field in itsinclusion of investigators from a wide variety of disciplines such as:bioengineering, systems biology, developmental biology, clinical science,regenerative medicine and genetic epidemiology. 

Moreover, Vasculata 2011 will be a novel addition to the series byincorporating new programmatic elements that emphasize the mentorship oftrainees as well as major initiatives to expand the gender and racial/ethnicdiversity of biomedical scientists in the field. Overall, the Vasculata 2011conference promises to be an exciting and uniquely rich research trainingexperience.

Organizing Committee: 

GaryGibbons, MD, Morehouse School of Medicine 

KathyGriendling, PhD, Emory University 

HanjoongJo PhD, Georgia Institute of Technology and Emory University 

ArshedQuyyumi MD, Emory University

For this project, Dr. Sulchek will be studying multivalent protein adhesion in order to improve how well biosensors can bind target molecules. He hopes to create methods to watch the binding and unbinding of multiple protein bonds in quick succession and close proximity.

As part of the CAREER Award outreach component, Dr. Sulchek will work with local high schools to match biology students with physical science students into teams, in order to emphasize the overlapping nature of the scientific and engineering disciplines. The goal is to portray science and engineering in a more exciting and interesting light. Currently, there are two high school students working in Dr. Sulchek's lab this summer, testing out a concept to rapidly measure protein adhesion. After knowledge is gained from this trial run working with students, Dr. Sulchek will organize 10-20 teams in the next year to compete in a cross-disciplinary science fair.

Upon learning about this award, Woodruff School Chair Dr. Bill Wepfer said, "Congratulations! Along with your recent NIH R21 award, this is a tremendous affirmation of your research program." Dean of Engineering, Dr. Don Giddens said, "Great news, Todd, and a hearty congratulations!!" Further hats off came from Georgia Tech's President, Dr. G.P. "Bud" Peterson, "Congratulations! Off to a great start!"

Dr, Sulchek received both his M.S. and Ph.D. degrees (Applied Physics) from Stanford University in 2000 and 2006, respectively. He earned his B.A. (Physics and Mathematics) at Johns Hopkins University in 1996. Dr. Sulchek started at Georgia Tech in June 2008 as an Assistant Professor. Prior to his current appointment, he was a staff scientist at Lawrence Livermore National Lab.

Currently, there are twenty-seven Woodruff School faculty members who have at one time held a CAREER Award. In addition, the Woodruff School has fifteen Ph.D. graduates who have won these awards and are on the faculty of universities other than Georgia Tech.