We would like to congratulate Dr. Yale Cohen, Ph.D., on his recent appointment as the new Graduate Group Chair for Penn’s Department of Bioengineering. The Graduate Group is a group of faculty that graduate students in bioengineering can choose from to collaborate with on lab research. The Group includes members from nearly all of Penn’s schools, including Penn Engineering, Penn Dental, Penn Medicine, Penn Vet, and the School of Arts and Sciences.
Dr. Cohen specializes in otorhinolaryngology as his primary department, with research areas in computational and experimental neuroengineering. He will take over the role of Graduate Group Chair from Dr. Ravi Radhakrishnan, Ph.D, professor of bioengineering and chemical and biomolecular engineering, whose research specializes in cellular, molecular, and theoretical and computational bioengineering. During his tenure as Graduate Group Chair, Dr. Radhakrishnan says that “the most enjoyable part was the student talks during bioengineering seminars, and the talks at the bioengineering graduate student research symposium,” noting the way they made him realize the “depth and breadth of our graduate group, and how accomplished our students are.”
Also during his time as chair, Dr. Radhakrishnan says he was proud to expand the course BE 699 — the Bioengineering Department’s required seminar for all Ph.D. candidates — to include discussions of leadership and soft-skills, as well as instituting individualized development plans to help students track their work. In looking forward to Dr. Cohen’s appointment to the role, Dr. Radhakrishnan says that he is “a natural and accomplished scientist, educator, and amazing leader who connects so readily and well with our students and faculty.”
Dr. Cohen, looking forward to taking on his new role, says that he hopes to improve programs like the Graduate Association of Bioengineers (GABE) and the mentoring of graduate students so that they can access the wide range of wisdom that comprises the faculty, students, staff, and alumni associated with the Graduate Group. “I am thrilled to be the new chair of the BE Graduate Group and welcome your input and comments on how to improve an already outstanding program,” says Dr. Cohen.
Tenured faculty at Penn Engineering demonstrate teaching excellence and international leadership in their fields of study and research collaborations.
Associate Professor in Bioengineering Chow’s research focuses on the discovery and engineering of photoreceptors and sensory proteins for manipulating and monitoring the physiology of genetically targeted cells, and the application of these tools to reveal principles of cellular dynamics. His work has advanced the rational design of light activated proteins and the use of optogenetic reagents to study cell signaling.
Associate Professor in Bioengineering Issadore’s research combines microelectronics, microfluidics, and nanomaterials to create miniaturized platforms for the diagnosis of disease. His work has the potential to radically change the way we diagnose and treat diseases by bringing the technologies out of the lab and directly to the point of care.
Dongeun (Dan) Huh
Associate Professor in Bioengineering Huh’s research aims to develop innovative bioengineering tools and technologies using biologically inspired design principles and micro- and nano-scale engineering techniques to create systems that mimic the structure and function of human physiological systems.
Linh Thi Xuan Phan
Associate Professor in Computer and Information Science Phan’s work focuses on making cyber-physical systems (CPS) safer, faster, and more secure, both by strengthening the theoretical foundations and by developing practical solutions. Her recent projects include a cloud platform with real-time capabilities, a new diagnosis technique for timing-related faults, and new ways to defend CPS against attacks from insiders and/or external attackers.
Associate Professor in Chemical and Biomolecular Engineering Patel’s research strives to achieve a molecular-level understanding of solvation and transport in aqueous and polymeric systems, with applications ranging from the prediction of protein interactions to the design of advanced materials for water purification and energy storage. His group combines principles of statistical mechanics and liquid state theory with state-of-the-art molecular modeling and atomistic simulation techniques to study these biological, nanoscopic and polymeric systems.
Associate Professor in Chemical and Biomolecular Engineering Vojvodic’s research focuses on theory and computation-driven materials design. Her lab uses computational frameworks to obtain fundamental understanding of surface and interface properties of complex materials that can be used to develop theoretical models for chemical transformations and energy conversion. These models have been used to predict new catalyst materials for several chemical reactions which have been experimentally synthesized and tested, validating the desired properties of the computationally predicted catalyst material.
De la Fuente, who started at Penn earlier this year, was recognized because he “is pioneering the computerization of biological systems for the development of transformative biotechnologies designed to solve societal grand challenges such as antibiotic resistance.”
Heart disease is currently the leading cause of death in the United States, resulting in about 630,000 deaths every year according to the Center for Disease Control. One of the most common side effects of heart disease is damage to blood vessels and cardiac tissue, which can ultimately lead to conditions like high blood pressure, arrhythmia, and even cardiac arrest. In serious cases of irreversible heart damage, often the only option for patients is a full heart transplant, and efforts to engineer vascularized cardiac tissue grafts have proved challenging in research so far.
But researchers Ying Zheng, Ph.D., and Charles Murry, M.D., Ph.D., both of whom have joint appointments in Bioengineering at the University of Washington, have found success in using human microvascular grafts to create working blood vessels in vitro to treat infarcted rat hearts. The new heart muscle, developed from human embryonic stem cell-derived endothelial cells in petri dishes, was grown with a focus on not only being able to easily integrate it in vivo, but also in creating a patch of vasculature that closely mirrored that of the heart. In concentrating more on the mechanical aspects of the blood vessel network, Zheng and Murry were able to better restore normal blood flow to the damaged rat hearts after integration of the grafts. The study appears in a recent edition of Nature Communications.
Another team of bioengineers, led by Michael Sacks, Ph.D. at the University of Texas at Austin, recently invented a software-based method for repairing mitral valves in the heart. Their work, published in the International Journal for Numerical Methods in Biomedical Engineering, uses computational modeling techniques to create a noninvasive way of simulating repairs to the mitral valve, which will allow for a better prediction of surgical procedures and postoperative side effects on a more patient-specific basis. This ability to know which treatment plan may be best-suited for a given patient is important especially for valve repair, as heart valves are notoriously difficult to model or image due to the complexity of their functions. But through the use of advanced technology in 3D echocardiography, Sacks and his team say that their new model is accurate enough to rely on in clinical settings.
Virtual Reality Assists in the Evaluation of Surgery
Any form of surgery is always a high risk procedure, as it is subject to a wide variety of sources of human error and irregularity, even with the best surgeons. Certainly, there should be a system in place to not only continually assess the knowledge of surgeons throughout their careers, but also to evaluate their practices and techniques during operation. Such an evaluation, however, would put patients at risk during the assessment of the surgeon.
But now a team of researchers from Rensselaer Polytechnic Institute has developed a way of simulating colorectal surgical procedures using virtual reality technology. Suvranu De, Sc.D. — the J. Erik Jonsson ‘22 Distinguished Professor of Engineering and Head of the Department of Mechanical, Aerospace and Nuclear Engineering with joint appointments in Biomedical Engineering and Information Technology and Web Science —leads the project which incorporates both visual and tactile feedback for users to employ as a tool for both training and evaluating colorectal surgeons. While virtual reality simulators have been used for similar applications related to procedures like the colonoscopy, they have yet to be fully developed for open surgical procedures, because of the difficulties in creating a fully engaged and immersive environment. Nonetheless, De and his team hope that their work will lead to the creation of the first “Virtual Intelligent Preceptor,” which will allow for more advanced technological innovations in aspects of surgical education that have so far been difficult to standardize. Support for the project comes from the National Institute of Biomedical Imaging and Bioengineering (NBIB).
Penn BE’s Dr. Bassett on Understanding Knowledge Networks in the Brain
As a network neuroscientist, Danielle Bassett, Ph.D., Eduardo D. Glandt Faculty Fellow and Associate Professor in the Department Bioengineering, brings together insights from a variety of fields to understand how the brain’s connections form and change: mathematics, physics, electrical engineering and developmental biology, to name a few. Bassett’s recent work on the learning process also draws from linguistics, educational theory and other domains even further afield.
The intersection and interaction of knowledge from multiple sources doesn’t just describe Bassett’s methodology; it’s at the heart of her research itself. At the Society for Industrial and Applied Mathematics’ Annual Meeting last year, Bassett provided an address on how the structure of knowledge networks can influence what our brains can do when it comes to learning new things.
The field of bioengineering is constantly growing, and new programs are always in development. Boise State University has announced the launch of a new doctoral program in bioengineering that will begin in the fall of 2019. Developed through the collaboration of the university’s College of Health Sciences, College of Engineering, Graduate College, and College of Arts and Sciences, this new opportunity to do research in the field of bioengineering will have three study tracks available in biomechanics, mechanobiology, and human performance.
The new biomedical engineering department at the University of Massachusetts Amherst has announced the department’s first faculty appointments. The founding department head will be Professor Tammy L. Haut Donahue, Ph.D., whose research focus is on the biomechanics of the musculoskeletal system. Another professor joining the department’s new faculty is Seth W. Donahue, Ph.D., who has also done research in the field of biomechanics, and specifically how it pertains to tissue regeneration.
Since we last posted, there have also been several significant academic appointments in the field of Bioengineering. This week, we would like to congratulate Bruce Tromberg, Ph.D., on his appointment as the director of the National Institute of Biomedical Imaging and Bioengineering (NIBIB). Dr. Tromberg is currently a Professor with appointments in Biomedical Engineering and Surgery at the University of California at Irvine, where he leads research in bioimaging and biophotonics. He has also served on the External Advisory Board of NIH P41 Center for Magnetic Resonance and Optical Imaging here at Penn since 2009, and has also given several lectures here on his work in bioimaging.
Secondly, we congratulate the University of Toronto’s Professor Warren Chan, Ph.D., who was recently named as a Tier 1 Canada Research Chair in Nanobioengineering. Professor Chan, who is also the director of the Institute of Biomaterials and Biomedical Engineering at the University of Toronto, conducts research in the field of nanotechnology for applications in the treatment and diagnosis of cancer and viral diseases.
And finally, we also want to congratulate Frank Pintar, Ph.D., on his appointment as the Founding Chair of the Marquette University and Medical College of Wisconsin. Dr. Pintar’s research in bioengineering involves the study of the biomechanics involved with brain and spinal cord injury, with a focus on motor vehicle crash trauma.
Medical researchers have long been baffled by the need to find safe and effective treatment for a common condition called temporomandibular joint dysfunction (TMD). Affecting around twenty-five percent of the adult population worldwide, TMD appears overwhelmingly in adolescent, premenopausal women. Many different factors such as injury, arthritis, or grinding of the teeth can lead to the disintegration of or damage to the temporomandibular joint (TMJ), which leads to TMD, although the root cause is not always clear. A type of temporomandibular disorder, TMD can result in chronic pain in the jaw and ears, create difficulty eating and talking, and even cause occasional locking of the joint, making it difficult to open or close one’s mouth. Surgery is often considered a last resort because the results are often short-lasting or even dangerous.
The state of TMD treatment may change with the publication of a study in Science Translational Medicine. With contributions from researchers at the University of California, Irvine (UCI), UC Davis, and the University of Texas School of Dentistry at Houston, this new study has successfully implanted engineered discs made from rib cartilage cells into a TMJ model. The biological properties of the discs are similar enough to native TMJ cells to more fully reduce further degeneration of the joint as well as potentially pave the way for regeneration of joints with TMD.
Senior author Kyriacos Athanasiou, PhD, Distinguished Professor of Biomedical Engineering at UCI, states the next steps for the team of researchers include a long-term study to ensure ongoing effectiveness and safety of the implants followed by eventual clinical trials. In the long run, this technique may also prove useful and relevant to the treatment of other types of arthritis and joint dysfunction.
Advances in Autism Research
Currently, diagnosis of autism spectrum disorders (ASD) has been limited entirely to clinical observation and examination by medical professionals. This makes the early identification and treatment of ASD difficult as most children cannot be accurately diagnosed until around the age of four, delaying the treatment they might receive. A recent study published in the journal of Bioengineering & Translational Medicine, however, suggests that new blood tests may be able to identify ASD with a high level of accuracy, increasing the early identification that is key to helping autistic children and their families. The researchers, led by Juergen Hahn, PhD, Professor and Department Head of Biomedical Engineering at the Rensselaer Polytechnic Institute, hope that after clinical trials this blood test will become commercially available.
In addition to work that shows methods to detect autism earlier, the most recent issue of Nature Biomedical Engineering includes a study to understand the possible causes of autism and, in turn, develop treatments for the disease. The breakthrough technology of Cas9 enzymes allowed researchers to edit the genome, correcting for symptoms that appeared in mice which resembled autism, including exaggerated and repetitive behaviors. This advance comes from a team at the University of California, Berkeley, which developed the gene-editing technique known as CRISPR-Gold to treat symptoms of ASD by injecting the Cas9 enzyme into the brain without the need for viral delivery. The UC Berkeley researchers suggest in the article’s abstract that these safe gene-editing technologies “may revolutionize the treatment of neurological diseases and the understanding of brain function.” These treatments may have practical benefits for the understanding and treatment of such diverse conditions as addiction and epilepsy as well as ASD.
Penn Professor’s Groundbreaking Bioengineering Technology
Our own D. Kacy Cullen, PhD, was recently featured in Penn Today for his groundbreaking research which has led to the first implantable tissue-engineered brain pathways. This technology could lead to the reversal of certain neurodegenerative disorders, such as Parkinson’s disease.
With three patents, at least eight published papers, $3.3 million in funding, and a productive go with the Penn Center for Innovation’s I-Corps program this past fall, Dr. Cullen is ready to take this project’s findings to the next level with the creation of a brand new startup company: Innervace. “It’s really surreal to think that I’ve been working on this project, this approach, for 10 years now,” he says. “It really was doggedness to just keep pushing in the lab, despite the challenges in getting extramural funding, despite the skepticism of peer reviewers. But we’ve shown that we’re able to do it, and that this is a viable technology.” Several Penn bioengineering students are involved in the research conducted in Dr. Cullen’s lab, including doctoral candidate Laura Struzyna and recent graduate Kate Panzer, who worked in the lab all four years of her undergraduate career.
In addition to his appointment as a Research Associate Professor of Neurosurgery at the Perelman School of Medicine at the University of Pennsylvania, Dr. Cullen also serves as a member of Penn’s Department of Bioengineering Graduate Group Faculty, and will teach the graduate course BE 502 (From Lab to Market Place) for the BE Department this fall 2018 semester. He also serves as the director for the Center of Neurotrauma, Neurodegeneration, and Restoration at the VA Medical Center.
New Prosthetics Will Have the Ability to Feel Pain
New research from the Department of Biomedical Engineering at Johns Hopkins University (JHU) has found a way to address one of the difficult aspects of amputation: the inability for prosthetic limbs to feel. This innovative electronic dermis is worn over the prosthetic, and can detect sensations (such as pain or even a light touch), which are conveyed to the user’s nervous system, closing mimicking skin. The findings of this study were recently published in the journal ScienceRobotics.
While one might wonder at the value of feeling pain, both researchers and amputees verify that physical sensory reception is important both for the desired realism of the prosthetic or bionic limb, and also to alert the wearer of any potential harm or damage, the same way that heat can remind a person to remove her hand from a hot surface, preventing a potential burn. Professor Nitish Thakor, PhD, and his team hope to make this exciting new technology readily available to amputees.
People and Places
Women are still vastly outnumbered in STEM, making up only twenty percent of the field, and given the need for diversification, researchers, educators, and companies are brainstorming ways to proactively solve this problem by promoting STEM subjects to young women. One current initiative has been spearheaded by GE Healthcare and Milwaukee School of Engineering University (MSOE) who are partnering to give middle school girls access to programs in engineering during their summer break at the MSOE Summer STEM Camp, hoping to reduce the stigma of these subjects for young women. GE Girls also hosts STEM programs with a number of institutions across the U.S.
The National Science Policy Network (NSPN) “works to provide a collaborative resource portal for early-career scientists and engineers involved in science policy, diplomacy, and advocacy.” The NSPN offers platforms and support including grant funding, internships, and competitions. Chaired and led by emerging researchers and professors from around the country, including biomedical engineering PhD student Michaela Rikard of the University of Virginia, the NSPN seeks to provide a network for young scientists in the current political climate in which scientific issues and the very importance of the sciences as a whole are hotly contested and debated by politicians and the public. The NSPN looks to provide a way for scientists to have a voice in policy-making. This new initiative was recently featured in the Scientific American.
Upon its original founding in 2000, the Bill and Melinda Gates Foundation has included the eradication of malaria as part of its mission, pledging around $2 billion to the cause in the years since. One of its most recent initiatives is the funding of a bioengineering project which targets the type of mosquitoes which carry the deadly disease. Engineered mosquitoes (so-called “Friendly Mosquitoes”) would mate in the wild, passing on a mosquito-killing gene to their female offspring (only females bite humans) before they reach maturity. While previous versions of “Friendly Mosquitoes” have been met with success, concerns have been raised about the potential long-term ecological effects to the mosquito population. UK-based partner Oxitec expects to have the new group ready for trials in two years.
We cover many highly complex innovations here, and many of these innovations solve vexing problems in the healthcare field. However, sometimes the problems addressed by these innovations are not particularly complex, even if the impact is economically significant. For instance, venipuncture — commonly referred to as a blood draw — is one of the most basic medical procedures and is mainly performed by medical technicians. There are two problems with venipuncture, however. First, either the health specialist might not be very good at drawing blood or the patient might be non-compliant. Second, the sample must be sent to a lab for analysis by someone else days later, making the costs for blood draws high. A device that could combine these procedures has been considered the “holy grail” of blood testing.
Engineers at Rutgers University might have found this holy grail. Reporting in the journal Technology, the engineers, led by Martin L. Yarmush, PhD, Paul & Mary Monroe Chair and Professor in the Department of Biomedical Engineering at Rutgers, describe how they combined robotics and lab-on-chip technology to create a point-of-care blood testing device. In the article, the authors report the testing of their device with a blood-like fluid loaded with microbeads and with model veins. The automated blood draw technique is the same across all patients, and the analysis of blood can occur immediately after isolating the blood, making it safer, faster, and more cost-effective. Animal testing should follow soon, and a longer-term view envisions expansion of the initial model to accommodate different types of blood testing.
Preventing a Water Crisis
One of the looming crises humankind faces is access to clean water. Nearly one third of the human population either lacks access or has threatened access to potable water. The rapid population growth in the southern hemisphere means that this proportion will increase, even as preventable water-borne diseases like cholera take their toll. Solutions such as desalinization or mass purification could provide solutions, but they are currently prohibitively expensive and create environmental problems of their own. Less expensive and less burdensome solutions continue to be sought.
Now, engineering professors from Carnegie Mellon University (CMU) might have identified a solution. Robert Tilton, PhD, and Todd Przybycien, PhD, both Professors in the Departments of Biomedical Engineering and Chemical Engineering at CMU, are lead authors on a new study in ACS Langmuirdescribing how proteins produced by the drumstick tree — a very hearty tree native to India that is conducive to a broad range of climate and is already widely cultivated for its fruit and oils — could be used to address water scarcity. The authors exploited the knowledge that cationic protein-modified sand can be used to filter water and showed how to engineer drumstick tree proteins to optimize the filtration process. Testing showed that the authors’ engineered filtration system was more effective and might even lend itself to repeated use.
Innovating for Pediatric Care
Penn Health-Tech is one of the newer initiatives here at the University of Pennsylvania dedicated to catalyzing medical device innovation. However, Penn isn’t the only Philadelphia institution dedicating resources to innovation and invention in medical devices. In the June issue of DOTmed HealthCare Business News magazine, Andrew Rich, who is Senior Director of Biomedical Engineering at the Children’s Hospital of Philadelphia (CHOP), discusses the initiatives being undertaken at CHOP to integrate data from medical devices with electronic health records, as well as other projects.
Improving Limb Prosthetics
Prosthetics have provided a solution for amputees for more than a century, and engineering has been the source of many improvements over that time. A significant goal of scientists studying prosthetics has been the ability of patients to control their artificial limbs with their own neuromuscular signals. While progress has been made in this direction with machine learning, many patients have to spend a lot of time “training” their prostheses to react properly to these signals, which can be deeply discouraging to patients who have already experienced trauma.
A possible solution has been suggested by He (Helen) Huang, PhD, Professor of Biomedical Engineering in the joint department of the University of North Carolina and North Carolina State University, and Stephanie Huang, PhD, Research Assistant Professor in the joint department. In a paper newly published in IEEE Transactions on Neural Systems and Rehabilitation Engineering, the professors used the muscle activation patterns of the residual muscles remaining in patients after amputation. They tested their approach in 10 patients and found highly statistically significant improvement in movement accuracy. Testing in more subjects and allowing users longer training periods during testing could both yield even more impressive outcomes.
People and Places
Synthetic biologists at Colorado State University received a $1.7 million grant from the Defense Advanced Research Projects Agency (DARPA) to genetically engineer sporopollenin — a naturally occurring, chemically inert polymer found in pollen grains — to create what they hope will be the world’s strongest material. Early success could lead to another $2 million in DARPA funding in a couple of years. Matt Kipper, PhD, Associate Professor of Chemical and Biological Engineering, is a co-investigator on the grant.
Rose-Hulman Institute of Technology in Terre Haute, Indiana, has announced that it will be adding a new major in engineering design to its curriculum. Patsy Brackin, PhD, Professor of Mechanical Engineering, will lead the new program as director.
Dolphins are among the most intelligent creatures on earth, showing behaviors such as teaching, learning, cooperation, delayed gratification, and other markers of high intelligence. Dolphins communicate vocally with one another, although we aren’t sure exactly what they communicate. While this communication isn’t “language” as humans define it, it uses echolocation — finding objects and orienteering on the basis of reflected sound — which humans don’t use in their communications.
Now, we have new information about dolphin echolocation thanks to an article recently published in the Journal of the Acoustical Society of America by mathematicians and biomedical engineers in Sweden. On the basis of earlier research finding that dolphin echolocation signals consist of two tones, rather than one, the new study finds that these two tones are emitted at slightly different times and that the sound waves have a Gaussian shape, similar to a bell curve. Using a mathematical algorithm, the authors successfully simulated echolocation signals in the lab.
The findings explain how dolphins use echolocation effectively but could also contribute to more accurate sound-based diagnostic techniques — particularly ultrasound, which relies heavily on methods similar to echolocation to provide images of moving tissues within the body, e.g., prenatal imaging and heart contraction.
Modeling Diseased Blood Vessels for Drug and Device Testing
Drugs and devices require extensive testing before they are approved by regulatory agencies and used to treat human patients. Tissue engineering has helped bridge the gap between a promising idea and its use in a patient by creating technologies that mimic the complex structure of human tissue. Most of these technologies focus on the engineering of healthy tissues and much less on constructing models of diseased tissue. These models of diseased tissue may be useful for designing treatments for diseases and understanding how diseases are caused.
In this light, Marsha W. Rolle, PhD, Associate Professor of Biomedical Engineering at Worcester Polytechnic Institute (WPI), is working to create engineered blood vessels that are already diseased as a way to test possible treatments. With three years of funding from the National Institutes of Health’s National Heart Lung and Blood Institute amounting to nearly $500,000, Dr. Rolle and her research team create these damaged vessels by engineering smooth muscle cells to form tubes 2 mm in diameter. These synthetic vessels are then modified to resemble features of diseases. For example, growth factors attached to microspheres can encourage the growth of tissue in small parts of the vessel wall, eventually becoming areas of narrowing in the vessel. Similarly, other factors could lead to changes in the vessel that resemble aneurysms. In both cases, the function of the microengineered vessel could be measured as the change happens, providing insight into either vascular stenosis or aneurysms, neither of which is possible in humans.
Dr. Rolle’s first step will be to test the damaged engineered vessels with existing medications. If successful, this new technique could be used for testing of new drugs and devices prior to testing in animals.
New Heart Implant Can Deliver Drug
Speaking of damage to the circulatory system, a new article in Nature Biomedical Engineering details how engineers at MIT, Harvard, and Trinity College, Dublin, created a heart implant that can deliver targeted therapy to damaged heart tissue. The authors, led in part by Conor J. Walsh, PhD, and David J. Mooney, PhD, of Harvard, created a device called Therepi, approximately 4 mm in size, which is deployed with a hypodermic. Once placed, a reservoir of medicine within the Therepi treats the damaged heart muscle. In addition, it can be refilled without needing to remove the implant. The Nature Biomedical Engineering study is limited to testing in rats, but the authors see testing in humans in the near future.
Erdős-Rényi Prize for Penn Professor
Danielle S. Bassett, PhD, Eduardo D. Glandt Faculty Fellow and Associate Professor of Bioengineering at the University of Pennsylvania, has been named the 2018 recipient of the Erdős-Rényi Prize in Network Science by the Network Science Society (NetSci). NetSci has recognized Dr. Bassett for “fundamental contributions to our understanding of the network architecture of the human brain, its evolution over learning and development, and its alteration in neurological disease.” Dr. Bassett will receive the award and deliver a lecture on June 14 at the International Conference on Network Science in Paris. She is the seventh scientist and fourth American to receive the prize.
The Erdős-Rényi Prize is awarded annually to a scientist younger than 40 years old for his/her achievements in the field of network science. It is named for the Hungarian mathematicians Paul Erdős, whose surname provided a measurement for research collaboration by academic mathematicians, and Alfréd Rényi, whose work focused on probability and graph theory. In network science, an Erdős-Rényi model is a model for generating random graphs. Dr. Bassett’s research applies the principles of network science in neuroscience, with the intention of understanding the brain better by modeling the networks and circuits of our most complex organ.
People and Places
Two new centers dedicated to health sciences are opening. Western New England University opened its new Center for Global Health Engineering in April, with Michael J. Rust, PhD, Associate Professor of Biomedical Engineering, as the codirector under director Christian Salmon, PhD. Elsewhere, Northwestern University launched a new center — the Center for Advanced Regenerative Engineering — with Guillermo Ameer, PhD, Daniel Hale Williams Professor of Biomedical Engineering and Surgery at Northwestern, as founding director.
Finally, Joseph J. Pancrazio, Ph.D., Professor of Bioengineering at the University of Texas at Dallas and Associate Provost, has been named Vice President for Research. Before moving to UT Dallas in 2015, Dr. Pancrazio was the founding chair of Bioengineering at George Mason University in Virginia.
Disorders of or damage to the cornea — the clear covering over the lens of the eye — can be threatening to vision, and for the last century, corneal transplantation has been a cornerstone of treatment for these conditions. However, corneal transplants are complicated by two key facts: first, as with virtually all transplant procedures, donor organs are in short supply; and second, rejection is common, and recipients of transplants face repeated procedures or a lifetime of steroid eyedrops to prevent rejection.
One way of obviating these issues is the use of synthetic materials, which can now be manufactured with three-dimensional printing. In a new study from scientists at the Institute of Genetic Medicine at Newcastle University in the UK, to be published this summer in Experimental Eye Research, synthetic corneal tissue was 3D printed using a bioink loaded with encapsulated keratocytes (corneal cells), in combination with computer modeling based on actual corneas. The study is only proof to show that printing a biological replicate of the cornea is possible, but it lays the groundwork for future studies in animals.
Engineering Brain Recovery
One of the reasons why stroke is such a damaging event is the inability of damaged brain tissue to regenerate. Angiogenesis, the growth of new blood vessels, can help to regenerate brain tissue but properly guiding the process of angiogenesis is rather difficult.
However, a new report in Nature Materials indicates success using an injectable biogel for this purpose. In the report, a team led by Tatiana Segura, PhD, Professor of Biomedical Engineering at Duke with colleagues at UCLA, details its engineering of an injectable gel using nanoparticles consisting of heparin (a blood-thinning agent to prevent unwanted blood clotting) and vascular endothelial growth factor (VEGF) to stimulate brain regeneration. After injecting the gel in a mouse model of stroke, the mice showed a significant improvement in recovery compared to animals not receiving the engineered nanomaterial.
Here at Penn, D. Kacy Cullen, PhD, Research Associate Professor of Neurosurgery in the Perelman School of Medicine, has been investigating the use of implantable tissue-engineered brain pathways to treat and perhaps reverse the effects of neurodegnerative diseases like Parkinson’s disease. Penn Today has the story, with video of Dr. Cullen and photos and quotes from several of our own Bioengineering students.
Streamlining Environmental Bioengineering
Outside of the health sciences, bioengineering has applications in diverse fields, including energy development and environmental protection. Biofuels are one application for bioengineering that received a major boost recently. In an article published in NPJ Systems Biology and Applications, engineers from the US Department of Energy’s Lawrence Berkeley National Laboratory describe how they used machine learning to better predict the ability of engineered microbes to produce biofuel. With this information, they can then better adjust fuel-producing microbial pathways to maximize production. The machine learning model is a significant improvement over earlier, traditionally algorithmic approaches requiring complex differential equations. The time saved could, over generations of adjustments, result in a significant increase in output.
More on Pilots
Last week, we discussed how the cognitive load borne by airline pilots differs between simulated and real flight. Other scientists, it turns out, are looking at ways that pilots — in particular, fighter pilots — can overcome fatigue. With more than $1 million in grants from the US Department of Defense, Merhavan Singh, PhD, Dean of the Graduate School of Biomedical Sciences at the University of North Texas Health Science Center, and Kai Shen, PhD, Associate Professor in the Department of Chemistry and Forensic Science at Savannah State University in Georgia, are investigating compounds targeting the sigma 1 receptor, which the scientists believe could combat fatigue and also have neuroprotective effects if activated. This is particularly important among fighter pilots serving in conflict, who are often sleep deprived but must remain alert during missions.
People and Places
Having achieved success in its mission, the University of Alabama at Birmingham’s PREP Scholars Program, which supports underrepresented minority students in pursuing graduate study in bioengineering and biomedical engineering, has received an additional $1.8 million in support from the National Institutes of Health. The money will enable the funding of 40 students over the next five years.
Jeffrey Collins Wolchok, PhD, and Kartik Balachandran, PhD, both associate professors in the Department of Biomedical Engineering at the University of Arkansas, have received a $375,000 grant from the National Science Foundation to study the long-term effects of multiple concussions on the brain. With the increased emphasis in the scientific community and media on traumatic brain injury and chronic traumatic encephalopathy, including among former athletes, the two scientists will develop brain on a chip technology to examine the issue.
Finally, this week, the Best College Reviews website published its Top 10 list of online Master’s programs in biomedical engineering. Purdue University’s program finished in first place, with appearances on the list by Colorado State, UC Riverside, Stevens Tech, and Worcester Tech.
Melanoma is a common form of skin cancer that is most often successfully treated by removal of the cancerous cells. However, malignant forms of melanoma can metastasize and become deadly. The significance of malignant melanoma is evident in its incidence – melanoma is the fifth most common cause of deaths from cancer in the US. Treating melanoma relies on using biopsy samples to determine the virulence of the cancer. However, the biopsy process is invasive and painful, and it can even be disfiguring.
Addressing this issue, Jesse Wilson, PhD, Assistant Professor in the Department of Electrical and Computer Engineering and in the School of Biomedical Engineering at Colorado State University (CSU), is developing a virtual biopsy for the disease. Funded by a Young Investigator Award from the Melanoma Research Alliance and a grant from the Colorado Clinical and Translational Sciences Institute, Dr. Wilson’s virtual biopsy uses multiphoton microscopy, which normally requires the use of a costly short-pulse laser for optimal visualization; his research seeks to obviate the need for laser, thus rendering the process more broadly available.
Dr. Wilson intends to begin testing of his biopsy device on dogs from CSU’s veterinary school. Dogs also develop malignant melanoma, so the device will be used to gather data about each lesion that a dog develops. Once the imaging data are collected, the dogs will undergo normal biopsy and, if needed, treatment. In parallel, Dr. Wilson’s imaging algorithm will process the microscopy data collected prior to the biopsy, score it as malignant or not, and compare the predictions with the actual biopsy results to determine the new technique’s accuracy.
A Clue to Consciousness
Among the great mysteries in neuroscience is the nature of consciousness — that aspect of our psyche that allows us to observe that we are aware. We know that we have consciousness, but we aren’t sure why we do, nor do we fully understand the biological mechanisms that underlie consciousness.
A new study from scientists at Washington University in St. Louis might offer some clues, however. In the study, published in Neuron, the authors used a combination of calcium and hemoglobin imaging in mice to detect infra-slow spatiotemporal trajectories — essentially brain waves that are qualitatively different from other traditional electrical activity waves measured in the brain. These new waveforms were much slower than the activity of other traditional activity waves, and they traveled through different areas of the animals’ brains. The direction of the waves, moreover, changed on the basis of the level of consciousness of the mice.
Closer to home (and to humans), in a new article in Frontiers in Human Neuroscience, Hasan Ayaz, PhD, Associate Research Professor in the
School of Biomedical Engineering, Science and Health Systems at Drexel University, in collaboration with scientists from France, reports that the cognitive load of airline pilots differs significantly between pilots in the actual cockpit, compared to those using flight simulators. Dr. Ayaz and his colleagues used functional near infrared spectroscopy (fNIRS) for their comparisons. A future step for this research will be to integrate flight data recordings with the fNIRS data.
3D Printing Now Sweeter
Three-dimensional printing has become a vital resource in tissue engineering. However, the ability of commercial 3D printing technology to produce water-soluble glass — a key compound used in many tissue engineering processes — has been elusive because of the specific properties of the carbohydrates used to create this glass, which do not work with the technology used in available 3D printers.
However, this issue could be closer to a solution. In a new article in Additive Manufacturing, a team of scientists led by Rohit Bhargava, PhD, Founder Professor of Engineering in the Department of Bioengineering at the University of Illinois in Urbana-Champaign, reports that they have solved some of these problems. Using isomalt, a type of sugar alcohol, for their experiments, the authors were able to determine the characteristics inherent in the material necessary for 3D printing, as well as modeling the type of machinery necessary to use isomalt in a 3D printing process. Work on creating the 3D printing model recently published is still under way, but video of a bridge model has been published online here.
Seeing Like a Bat
Earlier this month, CLEO (the Conference on Lasers and Electro-Optics) held its annual meeting in San Jose, with a bioengineering contingent out in full force. Nader Engheta, PhD, the H. Nedwill Ramsey Professor with appointments in the Departments of Bioengineering, Electrical and Systems Engineering, and Materials Science and Engineering, was there and gave an interview with Optics & Photonics News. In the interview, Dr. Engheta discusses, among other things, bioinspired polarization — a developing field that seeks to enable people to see polarized light, which is visible to some animals, such as bats, but not to the human eye.
People and Places
Elon University in North Carolina will expand its current offerings in engineering in the coming year. In addition to a dual-degree program, Elon will offer for the first time an undergraduate degree program in engineering with an available concentration in biomedical engineering. Sirena Hargrove-Leak, PhD, has been named director of the new program.
As we’ve mentioned here before, surgery on the brain is particularly difficult because of the limited visibility afforded to the surgical field and the complexity of the organ. Because the brain’s gray matter can be easily damaged, a false move by a surgeon can have a lifetime of consequences. Better visualization during surgery could go a long way toward preventing accidental damage by the surgeon and minimize the removal of healthy brain tissue during tumor removal. However, ultrasound imaging of the brain has remained difficult because of the tendency of ultrasound waves to bounce off the skull.
To help solve this problem, a biomedical engineer at Vanderbilt University developed an ultrasound helmet to create perioperative ultrasound images of the brain. It could also provide a new variety of platform for brain-machine interfaces. According to Brett Byram, PhD, Assistant Professor of Biomedical Engineering at Vanderbilt, the helmet will eventually combine ultrasound with electroencephalography (EEG) to simultaneously visualize the brain and record its activity. Dr. Byram used a machine learning-based technique called aperture domain model image reconstruction (ADMIRE) to overcome the technical obstacle of ultrasound waves transmitting through the skull.
Although the initial thought of how to apply this technology was surgical, Dr. Bryram believes that the ability to detect blood flow to different parts of the brain in real time using ultrasound could facilitate the creation of technologies that would use this blood flow information, smoothed using ADMIRE, and EEG data to communicate with implants or robotic extensions to perform tasks.
A Roach Motel for Cancer
One key to curing cancer is preventing its spread, called metastasis. The mechanisms underlying metastasis are becoming clearer after years of research. Typically, the spread of cancer is the result of cancerous cells shed by a tumor affecting another organ after traveling via the bloodstream or lymphatic system. Unfortunately, sometimes this shedding is caused by the surgical procedure to remove the tumor. Therefore, preventing metastasis requires preventing these cells from circulating during and after the surgical procedure.
At the University of Texas at Arlington (UTA), Liping Tang, Ph.D., Professor of Biomedical Engineering at the University of Texas at Arlington, has patented what he calls a “roach motel” for cancer cells. Dr. Tang’s device, which is implanted under the skin, circulates cells of its own that attract circulating metastatic cells. The result of the device is the trapping of the cancer cells within the device and preventing them from traveling further. In vitro testing has been quite successful in a variety of cancers. Preclinical testing in animals will be the next step.
Injectable Alcohol Sensor Could Augment Treatment Programs
A few weeks ago, we detailed here how a scientist is developing DNA-based drug and alcohol screening tests. Recently a group of bioengineers at the University of California–San Diego (UCSD), led by Drew A. Hall, PhD, Assistant Professor of Electrical and Computer Engineering and an affiliate professor in the Department of Bioengineering at UCSD, has developed an injectable biosensor that can communicate blood alcohol levels to a wearable device. The sensor is a complementary metal–oxide semiconductor approximately 1 square millimeter in size and is designed for implantation under the skin surface. If in vivo testing proves successful, the system could be used as part of holistic approaches to preventing alcohol abuse among recovering alcoholics.
A Temperature-measuring Microscope
If you’ve used a microscope, then you’ve probably noticed that the samples viewed using microscopes are almost always on glass slides placed beneath the lens of the device. Now, in an article recently published in Nature Communications, an engineering team reports on their invention of a slide that can also measure temperature fluctuations in samples while maintaining microscopic imaging capability. Ruogang Zhao, PhD, assistant professor in the University at Buffalo Department of Biomedical Engineering, along with colleagues from our sister Departments of Electrical and Systems Engineering and Materials Science and Engineering here at Penn, coated a normal slide with 20-nanometer layers of gold activated by an external laser. Applications of the technology are numerous, and will be accelerated through mass production of slides, which the authors estimate would cost less than 10 cents each.
People and Places
Two large donations make our news this week. First, the University of Southern California received a $10 million gift from a retired ophthalmologist and his wife. The Dr. Allen and Charlotte Ginsburg Institute for Biomedical Therapeutics is being led by Mark S. Humayun, MD, PhD., Professor of Ophthalmology, Biomedical Engineering, and Cell and Neurobiology at USC. Across the country, the University of Maryland School of Medicine will establish the Robert E. Fischell Center for Biomedical Innovation with a $20 million gift from Robert Fischell, an inventor and holder of 200 patents. Distinguished University Professor and founding chair of the Fischell Department of Bioengineering William E. Bentley, PhD, will head the Fischell Center.
Also, it’s May, which means graduate news. Two special congratulations are in order. First, we congratulate Rowan University in New Jersey for graduating its first cohort of three newly minted PhDs in Biomedical Engineering. Also at the University of California at Davis, Tanishq Abraham will graduate next month with a Bachelor’s degree in Biomedical Engineering. In case that doesn’t sound like big news, bear in mind that Tanishq is only 14 years old. Tanisq will continue at Davis in studying in an MD/PhD program, which he hopes to finish before finishing his second decade of life.