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August 25, 2017August 25, 2017

Week in BioE (August 25, 2017)

Beyond Sunscreen

Excessive exposure to the sun remains a leading cause of skin cancers. The common methods of protection, including sunscreens and clothing, are the main ways in which people practice prevention. Amazingly, new research shows that what we eat could affect our cancer risk from sun exposure as well. Joseph S. Takahashi, Ph.D., who is chair of the Department of Neuroscience at the University of Texas Southwestern Medical Center’s Peter O’Donnell Jr. Brain Institute, was one of a team of scientists who recently published a paper in Cell Reports that found that by restricting the times when animals ate, their relative risk from exposure to ultraviolet light could change dramatically.

We tend to think of circadian rhythms as being among the reasons why we get sleepy at night, but the skin has a circadian clock as well, and this clock regulates the expression of certain genes by the epidermis, the visible outermost layer of the skin. The Cell Reports study found that food intake also affected these changes in gene expression. Restricting the eating to time windows throughout a 24h cycle, rather than providing food all the time, led to reduced levels of a skin enzyme that repairs damaged DNA — the underlying cause of sun-induced skin cancer. The study was conducted in mice, so no firm conclusions about the effects in humans can be drawn yet, but avoiding midnight snacks could be beneficial to more than your weight.

Let’s Get Small

Nanotechnology is one of the most common buzzwords nowadays in engineering, and the possible applications in health are enormous. For example, using tiny particles to interfere with the cancer signaling could give us a tool to stop cancer progression far earlier than what is possible today. One of the most recent approaches is the use of star-shaped gold particles — gold nanostars — in combination with an antibody-based therapy to treat cancer.

The study authors, led by Tuan Vo-Dinh, Ph.D., the R. Eugene and Susie E. Goodson Professor of Biomedical Engineering at Duke, combined the gold nanostars with anti-PD-L1 antibodies. The antibodies target a protein that is expressed in a variety of cancer types. Focusing a laser on the gold nanostars heats up the particles, destroying the cancer cells bound to the nanoparticles. Unlike past nanoparticle designs, the star shape concentrate the energy from the laser at their tips, thus requiring less exposure to the laser. Studies using the nanostar technology in mice showed a significant improvement in the cure rate from primary and metastatic tumors, and a resistance to cancer when it was reintroduced months later.

Nanotechnology is not the only new frontier for cancer therapies. One very interesting area is using plant viruses as a platform to attack cancers. Plant viruses stimulate a natural response to fight tumor progression, and these are viewed by some as ‘nature’s nanoparticles’. The viruses are complex structures, and offer the possibility of genetic manipulation to make them even more effective in the future. At Case Western Reserve University, scientists led by Nicole Steinmetz, Ph.D., associate professor of biomedical engineering, used a virus that normally affects potatoes to deliver cancer drugs in mice. Reporting their findings in Nano Letters, the authors used potato virus X (PVX) to form nanoparticles that they injected into the tumors of mice with melanoma, alongside a widely used chemotherapy drug, doxorubicin. Tumor progression was halted. Most importantly, the co-administration of drug and virus was more effective than packing the drug in the virus before injection. This co-administration approach is different than past studies that focus on packaging the drug into the nanoparticle first, and represents an important shift in the field.

Educating Engineers “Humanely”

Engineering curricula are nothing if not rigorous, and that level of rigor doesn’t leave much room for education in the humanities and social sciences. However, at Wake Forest University, an initiative led by founding dean of engineering Olga Pierrakos, Ph.D., will have 50 undergraduate engineering students enrolled in a new program at the college’s Downtown campus in Winston-Salem, N.C. The new curriculum plans for an equal distribution of general education/free electives relative to engineering coursework, with the expectation that the expansion of the liberal arts into and engineering degree will develop students with a broader perspective on how engineering can shape society.

People in the News

At the University of Illinois, Urbana-Champaign, Rashid Bashir, Ph.D., Grainger Distinguished Chair in Engineering and professor in the Department of Bioengineering, has been elevated to the position of executive associate dean and chief diversity officer at UIUC’s new Carle Illinois College of Medicine. The position began last week. Professor Michael Insana, Ph.D., replaces Dr. Bashir as department chair.

At the University of Virginia, Jeffrey W. Holmes, Ph.D., professor of biomedical engineering and medicine, will serve as the director of a new Center for Engineering in Medicine (CEM). The center is to be built using $10 million in funding over the next five years. The goal of the center is to increase the collaborations among engineers, physicians, nursing professionals, and biomedical scientists.

August 10, 2017August 17, 2017

Week in BioE (August 10, 2017)

Preventing Transplant Rejection

Organ transplantation is a lifesaving measure for people with diseases of the heart, lungs, liver, and kidneys that can no longer be treated medically or surgically. The United Network for Organ Sharing, a major advocacy group for transplant recipients, reports that a new person is added to a transplant list somewhere in America every 10 minutes. However, rejection of the donor organ by the recipient’s immune system remains a major hurdle for making every transplant procedure successful. Unfortunately, the drugs required to prevent rejection have serious side effects.

To address this problem, a research team at Cornell combined DNA sequencing and informatics algorithms to identify rejection earlier in the process, making earlier intervention more likely. The team, led by Iwijn De Vlaminck of the Department of Biomedical Engineering, report in PLOS Computational Biology that a computer algorithm they developed to detect donor-derived cell-free DNA, a type of DNA shed by dead cells, in the blood of the recipient could predict heart and lung allograft rejection with a 99% correlation with the current gold standard. The earlier that signs of rejection are detected, the more likely it is that an intervention can be performed to save the organ and, more importantly, the patient.

Meanwhile, at Yale, scientists have used nanoparticles to fight transplant rejection. Publishing their findings in Nature Communications, the study authors, led by Jordan S. Pober, Bayer Professor of Translational Medicine at Yale, and Mark Saltzman, Goizueta Foundation Professor of Chemical and Biomedical Engineering, used small-interfering RNA (siRNA) to “hide” donated tissue from the immune system of the recipient. Although the ability of siRNA to hide tissue in this manner has been known for some time, the effect did not last long in the body. The Yale team used poly(amine-co-ester) nanoparticles to deliver the siRNA that extended and extended its duration of effect, in addition to developing methods to deliver to siRNA to the tissue before transplantation. The technology has yet to be tested in humans, but provides an exciting new approach to help solve the transplant rejection challenge in medicine.

Africa in Focus

A group of engineering students at Wright State University, led by Thomas N. Hangartner, professor emeritus of biomedical engineering, medicine and physics, traveled to Malawi, a small nation in southern Africa, to build a digital X-ray system at Ludzi Community Hospital. Once on site, Hangartner and his student team trained the staff to use system on patients. The group hopes they have made a significant contribution to improving the standard of care in the country, which currently allocates only 9% of its annual budget to healthcare. While the project admitted has limited impact, it’s important to bear in mind that expanding public health on a global level is a game of inches. The developing world will rise to the standards of the developed world one village at a time, one hospital at a time.

Speaking of Africa, the recent Ebola outbreak in West Africa had global implications and prompted many international organizations to identify better methods to identify early signs of outbreak. Since diseases like Ebola can spread rapidly and aggressively, detecting the outbreak early can save thousands of lives. To this end, Tony Hu of Arizona State University’s School of Biological and Health Systems Engineering has partnered with the U.S. Army to develop a platform using porous silicone nanodisks that, coupled with a mass spectrometer, could be used to detect Ebola more quickly and less expensively. In particular, by determining the strain of the Ebola virus detected, treatment could be more specifically individualized for the patient. Dr. Hu presents the technology in a video available here.

Neurotech News

Karen Moxon, professor of biomedical and mechanical engineering at the University of California, Davis, recently showed that rats with spinal injuries recovered to a more significant extent when treated with a combination of serotonergic drugs and physical therapy. Dr. Moxon found that the treatment resulted in cortical reorganization to bypass the injury. Many consider combining two different drugs to treat a disease or injury; Moxon’s clever approach used a drug in combination with the activation of cortical circuits (electroceuticals), and approach that was not considered possible with some types of spinal cord injuries.

At Stanford, Karl Deisseroth, professor of bioengineering and of psychiatry and behavioral sciences, led a study team that recently reported in Science Translational Medicine that mice bred to have a type of autism could receive a genetic therapy that caused their brain cells to activate differently. Although the brains of the autistic mice were technically normal, the mice were unsocial and lacked curiosity. Treatment modulated expression of the CNTNAP2 gene, resulting in increased sociability and curiosity. Their findings could have tremendous implications for treating autism in humans.

Elsewhere in neurotech, Cornell announced its intention to create a neurotech research hub, using a $9 million grant from the National Science Foundation. Specializing in types of neurological imaging, the new NeuroNex Hub and Laboratory for Innovative Neurotechnology will augment the neurotech program founded at Cornell in 2015.

Academic Developments

Two important B(M)E department have developed new programs. In Montreal, McGill University has introduced a graduate certificate program in translational biomedical engineering (video here). Also at the annual meeting of the American Society for Engineering Education in Columbus, Ohio, an interdisciplinary group of scholars from Worcester Polytechnic Institute, including three professors of engineering, presented a paper entitled “The Theatre of Humanitarian Engineering.” The authors developed an experimental role-playing course in which the students developed a waste management solution for a city. According to the paper’s abstract, a core misunderstanding about engineering is the belief that it exists separately from social and political contexts. With the approach they detail, the authors believe they could address the largely unmet call for greater integration of engineering with the humanities and social sciences on the academic level.

August 3, 2017August 3, 2017

Week in BioE (August 3, 2017)

There’s news in bioengineering every week, to be sure, but the big story this past week is one that’s sure to continue appearing in headlines for days, weeks, and months — if not years — to come. This story is CRISPR-Cas9, or CRISPR for short, the gene-editing technology that many geneticists are viewing as the wave of the future in terms of the diagnosis and treatment of genetic disorders.

Standing for clustered regularly interspaced short palindromic repeats, CRISPR offers the ability to cut a cell’s genome at a predetermined location and remove and replace genes at this location. As a result, if the location is one at which the genes code for a particular disease, these genes can be edited out and replaced with healthy ones. Obviously, the impl CRISPR ications for this technology are enormous.

This week, it was reported that, for the first time, CRISPR was successfully used by scientists to edit the genomes of human embryos. As detailed in a paper published in Nature, these scientists edited the genomes of 50 single-cell embryos, which were subsequently allowed to undergo division until the three-day mark, at which point the multiple cells in the embryos were assessed to see whether the edits had been replicated in the new cells. In 72% of them, they had been.

In this particular case, the gene edited out was one for a type of congenital heart defect, and the embryos were created from the eggs of healthy women and the sperm of men carrying the gene for the defect. However, the experiments prove that the technology could now be applied in other disorders.

Needless to say, the coverage of this science story has been enormous, so here is a collection of links to coverage on the topic. Enjoy!

First Human Embryos Edited in U.S. (MIT Technology Review)
Yes, U.S. Scientists Edited an Embryo’s Genes, but Super-Babies Are a Ways Away (at Slate)
The Best Science Is Often Accidental (Baltimore Sun)
US Scientists Are Fixing Genetic Defects in Embryos. Should You Be Nervous? (PBS Newshour)

July 27, 2017July 27, 2017

Week in BioE (July 27, 2017)

The Brain in Focus

Brain At Caltech, scientists are exploiting the information generated by body movements, determining how the brain codes these movements in the anterior intraparietal cortex — a part of the brain beneath the top of the skull. In a paper published in Neuron, Richard A. Andersen, James G. Boswell Professor of Neuroscience at Caltech, and his team tested how this region coded body side, body part, and cognitive strategy, i.e., intention to move vs. actual movement. They were able determine specific neuron groups activated by different movements. With this knowledge, more effective prosthetics for people experiencing limb paralysis or other kinds of neurodegenerative conditions could benefit enormously.

Elsewhere in brain science, findings of chronic traumatic encephalopathy in football players have raised significant controversy. Seeking to better understand head impact exposure in young football players, scientists from Wake Forest University led by biomedical engineer Joel D. Stitzel, fitted athletes with telemetric devices and collected four years of data and more than 40,000 impacts. They report in the Journal of Neurotrauma that, while all players experienced more high magnitude impacts during games compared to practices, younger football players experienced a greater number of such impacts during practices than the other groups, and older players experienced a greater number during actual games. The authors believe their data could contribute to better decision-making in the prevention of football-related head injuries.

Up in Canada, a pair of McGill University researchers in the Department of Neurology and Neurosurgery — Professor Christopher Pack and Dave Liu, a grad student in Dr. Pack’s lab — found that neuroplasticity might apply to more parts of the brain than previously thought. They report in Neuron that the middle temporal area of the brain, which contributes to motion discrimination and can be inactivated by certain drugs, could become relatively impervious to such inactivation if pretrained. Their findings could have impacts on both prevention of and cures for certain types of brain injury.

The Virtues of Shellfish

If you’ve ever had a diagnostic test performed at the doctor’s office, you’ve had your specimen submitted to bioassay, a test in which living cells or tissue is used to test the sampled material. University of Washington bioengineer Xiaohu Gao and his colleagues used polydopamine, an enzyme occurring in shellfish, to increase the sensitivity of bioassays by orders of magnitude. As reported in Nature Biomedical Engineering, they tested the technology, called enzyme-accelerated signal enhancement (EASE), in HIV detection, finding that it was able to help bioassays identify the virus in tiny amounts. This advance could lead to earlier diagnosis of HIV, as well as other conditions.

Mussels are also contributing to the development of new bioadhesives. Julie Liu, associate professor of chemical engineering at Purdue, modeled an elastin-like polypeptide after a substance produced naturally by mussels, reporting her findings in Biomaterials. With slight materials, Dr. Liu and her colleagues produced a biomaterial with moderate adhesive strength that demonstrated the greatest strength yet among these materials when tested under water. The authors hope to develop a “smart” underwater adhesive for medical and other applications.

Science in Motion

Discussions of alternative forms of energy have focused on the big picture, such as alleviating our dependence on fossil fuels with renewable forms of energy, like the sun and wind. On a much smaller level, however, engineers are finding smaller energy sources — specifically people.

Reporting in ACS Energy Letters, a research team led by Vanderbilt’s Cary Pint, assistant professor in the Department of Mechanical Engineering and head of Vanderbilt’s Nanomaterials and Energy Devices Laboratory Nanomaterials and Energy Devices Laboratory, designed a battery in the form of an ultrathin black phosphorous device that can generate electricity as it is bent. Dr. Pint describes the device in a video here. Although it can’t yet power an iPhone, the possibility isn’t far away.

Moving Up

Two BE/BME departments have named new chairs. At the University of Utah, David Grainger, who previously chaired the Department of Pharmaceutics and Pharmaceutical Chemistry, will become chair of the Department of Bioengineering. Closer to home, Michael I. Miller became the new chair of the Department of Biomedical Engineering on July 1. Congratulations to them both!

July 6, 2017July 6, 2017

This Week in BioE (July 6, 2017)

Bioengineering of Genes and DNA

Since Watson and Crick published their initial studies detailing the double helix structure of DNA in the early 1960s, what we know about genetics and the nucleic acids underlying them has grown enormously. Consequently, what bioengineering can do with DNA and genes continually expands.

One fascinating bioengineering field that emerged in the past decade was DNA origami, which uses the well-established binding across DNA elements to create three-dimensional structures out of linear DNA sequences. Recent work has utilized this feature of DNA construction to make machines, rather than just parts, out of DNA.

Yonggang Ke, Ph.D., of Georgia Tech/Emory’s Department of Biomedical Engineering, constructed machines made of DNA that consist of arrays of units that can “switch” between “settings” by changing shape. A change in shape of one unit of an array can cause the other units in the array to shift; these changes are stimulated by inserting a previously deleted strand of DNA into the array. Although it has been known for some time that DNA could be used to store and transmit information, Dr. Ke’s research team proved for the first time that these arrays could be shaped physically into machines in the shapes of rectangles and tubes.

While we learn more about how to make DNA-based devices, we are also creating new technologies to manipulate DNA more rapidly. Scientists at Rutgers and Harvard developed a process whereby thousands of genes could be cloned at one time to create enormous libraries of proteins. To achieve this goal, the authors used a technology called LASSO (long-adapter single-strand oligonucleotide) probes, which they have already used to clone a library using a human microbiome sample.

Instead of the traditional process of cloning one gene at a time, the team led by Professor Biju Parekkadan, Ph.D. at Rutgers, invented a technology to clone hundred of genes simultaneously. These cloned DNA segments are much longer than the length of DNA cloned with standard techniques, allowing us to test the functional significance of these much longer DNA segments. The technology could impact a number of scientific fields because we will finally learn how long stretches of protein function — some parts may degrade other proteins, while other parts will interact and modify other proteins (e.g., phosphorylation, a key process in epigenetics). These new discoveries can be key for discovering new ways to engineer proteins and to manufacture new drugs that mimic the function of nature’s DNA products.

Using Sweat as a Biosensor

While the field learns more about the molecular-level control of DNA, we are also taking advantage of new micro- and nanoscale manufacturing processes to capture diagnostic information from easily accessible body fluids. Many clinical diagnostics use chemical measurements from blood to diagnose a disease or to take corrective action. This is not an ideal procedure because it requires either the collection of blood at a laboratory or the repeated collection of small blood volumes through a pinprick. Either one hurts.

Bioengineers at the University of Texas at Dallas developed a wearable diagnostic device to detect cortisol, glucose, and IL-6 in body sweat, eliminating any painful needle sticks. Its transmissions vary, but if optimized, the device could replace the painful and inconvenient practice of sticking one’s finger to obtain a drop of blood for glucose testing, which many patients with diabetes must do several times per day. Although insulin pumps have been available for some time, these are invasive devices that must be worn at all times.

June 22, 2017June 22, 2017

This Week in BioE (June 22, 2017)

Diversifying the Field

One of the ongoing issues in STEM (science, technology, engineering, and medicine) fields is a lack of diversity among students and faculty. Bioengineering stands out among other engineering fields because it enjoys terrific gender diversity. For example, about half of Penn Bioengineers are women, a feature of our class that goes back decades.

diversifying However, diversity extends well beyond gender. For example, the National Research Mentoring Network (NRMN) has been working to increase diversity, including among students with disabilities. A consortium of people and groups providing mentors for science students, the MRMN recently highlighted the American Association for the Advancement of Science’s (AAAS) Entry Point! program, which focuses on helping students with physical disabilities. Mentoring, it turns out is a big part of helping these students succeed.

Another recent development that should help to increase diversity in the field is the awarding of a $1 million grant from the National Science Foundation’s Directorate of Engineering to the University of Wisconsin, Madison, and the College of Menominee Nation (CMN), a native American college in Wisconsin, to collaborate in engineering research and education. The new grant builds on a program begun in 2010 between the colleges to build labs and facilitate the transfer of pre-engineering students from CMN to UWM.

Brain Science Developments

Speaking of education, three recent news stories discuss how we might be able to expedite the learning process, increase intelligence, and reward ourselves when we create art. In one of the stories, a company called Kernel is investing $100 million in research at the University of Southern California to determine whether using brain implants, which have been helpful in some patients with epilepsy, can be used to increase or recover memory. If successful, this may bridge one critical treatment gap in neurology. About one out of every three people with epilepsy don’t respond to drug treatment.

In the second story, scientists at the University of Texas at Dallas were awarded a $5.8 million contract from DARPA to investigate the role of vagus nerve stimulation in accelerated learning of foreign languages. Stimulating the peripheral nervous system to activate and train areas of the brain is one more example that our nervous system is connected in ways that we do not yet understand completely. The Department of Defense hopes to use the technology to more quickly train intelligence operatives and code breakers.

Finally, in a third story involving the brain, a professor at Drexel University used functional near-infrared spectroscopy to determine which parts of the brain were activated while participants were making art. Dr. Girija Kaimal’s team found that creative endeavors activate the brain’s rewards pathway, as well as elevating the participants’ self-opinion. So making art always made people feel good about themselves; now we know more of the reasons why.

May 9, 2017

Phytoplankton Research Earns Award

The Scripps Institution of Oceanography at the University of California, San Diego, announced last week that one of its faculty members, Andrew Barton, PhD, received a Simons Foundation Early Career Award to study phytoplankton — a type of algae that requires sunlight to survive and that serves as the basis for much of the marine food chain.

Dr. Barton’s research will use the Scripps Plankton Camera System, which provides real-time photographic images to monitor these phytoplankton. While not exactly offering the excitement or cuteness factor of the Golden Retriever Puppy Cam, this sort of technology is incredibly important to better understanding certain aspects of marine biology.

“This is an interesting project that brings cutting edge image-processing technology to the natural habitat to study complex organismal dynamics in the real-world setting,” says Brian Chow, PhD, assistant professor of bioengineering at the University of Pennsylvania. “Establishing the critical interplay between an organism’s form and function and the forces of its local and global environments are important problems in physical biology in general. Diatoms have long been studied by bioengineers interested in self-assembly, programmed assembly, biomineralization, and biomimicry, so the work may lead to some novel insights for our field.”

Congratulations to Dr. Barton on receiving this prestigious award.

April 25, 2017April 27, 2017

Tissue Engineering Makes Spinach Leaf Beat Like a Heart

One of the more interesting tissue engineering stories to emerge this past month was the successful finding of a team at Worcester Polytechnic Institute (WPI), which used the veins in spinach leaves as a scaffold that was then recellularized with stem cells that produce heart muscle cells. After three weeks, the transplanted cells showed the ability to contract like the heart does when it beats.

“Proper vascularization of artificial living tissues has been one of the most critical challenges of tissue engineering for decades. This is particularly problematic when the size of the engineered tissue increases.,” said Dongeun (Dan) Huh, PhD, Wilf Family Term Assistant Professor in the Department of Bioengineering at the University of Pennsylvania “This work takes an unusual yet ingenious approach to solving this long-standing problem.”

Below you can watch a short video of some of the investigators on the study talking about it.