Tag: biomedical engineering

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BE Seminar: “Reaction-Coupled Solid-State Nanopore Digital Counting: Towards Sensitive, Selective and Fast Nucleic Acid Testing” (Weihua Guan)

Weihua Guan, PhD

Speaker: Weihua Guan, Ph.D.
Assistant Professor
Department of Electrical Engineering & Department of Biomedical Engineering (courtesy)
Pennsylvania State University, University Park

Date: Thursday, April 8, 2021
Time: 3:00-4:00 PM EDT
Zoom – check email for link or contact ksas@seas.upenn.edu

Abstract:

Due to their conceptual simplicity, the nanopore sensors have attracted intense research interest in electronic single molecule detection. While considerable success has been achieved, the solid-state nanopores still face three significant challenges, including repeatable nanopore size control, introduction sensing specificity, and prolonged sensor response time at low concentrations. In this talk, I will discuss a calibration-free solid-state nanopore counting method and two representative applications in nucleic acid testing. One is an isothermal amplification-coupled nanopore counting for malaria analysis. The other is the CRISPR-cas12a-coupled nanopore counting for HIV analysis. Finally, I will also discuss how we can develop a fully integrated ‘sample-to-result’ nucleic acid testing device using the solid-state counting strategy. I believe the reaction-coupled solid-state nanopore digital counting could open a new avenue towards compact, robust, low-cost electronic nucleic acid testing at the point of care.

Weihua Guan Bio:

Weihua Guan received his Ph.D. degree in Electrical Engineering from Yale University in 2013 and did his postdoctoral training at Johns Hopkins University from 2013 to 2014. He joined the Department of Electrical Engineering at Pennsylvania State University in Jan 2015. He also held a courtesy appointment in the Department of Biomedical Engineering at Penn State. Dr. Guan’s research interests are in the multidisciplinary areas of micro- and nanotechnology, micro/nanofluidics, bioMEMS, lab-on-a-chip devices, and point-of-care devices. Dr. Guan’s research group at Penn State focuses on developing micro and nanoscale devices as well as novel sensing principles towards advanced medical diagnostics and testing. Dr. Guan is a member of IEEE, Engineering in Medicine and Biology Society, Biophysical Society, and American Physics Society. Among other honors, Dr. Guan is a recipient of the HHMI International Research Fellowship and NSF CAREER award.

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Penn, CHOP and Yale Researchers’ Molecular Simulations Uncover How Kinase Mutations Lead to Cancer Progression

by Evan Lerner

A computer model of a mutated anaplastic lymphoma kinase (ALK), a known oncogenic driver in pediatric neuroblastoma.

Kinases are a class of enzymes that are responsible for transferring the main chemical energy source used by the body’s cells. As such, they play important roles in diverse cellular processes, including signaling, differentiation, proliferation and metabolism. But since they are so ubiquitous, mutated versions of kinases are frequently found in cancers. Many cancer treatments involve targeting these mutant kinases with specific inhibitors.

Understanding the exact genetic mutations that lead to these aberrant kinases can therefore be critical in predicting the progression of a given patient’s cancer and tailoring the appropriate response.

To achieve this understanding on a more fundamental level, a team of researchers from the University of Pennsylvania’s School of Engineering and Applied Science and Perelman School of Medicine, the Children’s Hospital of Philadelphia (CHOP) and researchers at the Yale School of Medicine’s Cancer Biology Institute, have constructed molecular simulations of a mutant kinase implicated in pediatric neuroblastoma, a childhood cancer impacting the central nervous system.

Using their computational model to study the relationship between single-point changes in the kinase’s underlying gene and the altered structure of the protein it ultimately produces, the researchers revealed useful commonalities in the mutations that result in tumor formation and growth. Their findings suggest that such computational approaches could outperform existing profiling methods for other cancers and lead to more personalized treatments.

The study, published in the Proceedings of the National Academy of Sciences, was led by Ravi Radhakrishnan, Professor and chair of Penn Engineering’s Department of Bioengineering and professor in its Department of Chemical and Biomolecular Engineering, and Mark A. Lemmon, Professor of Pharmacology at Yale and co-director of Yale’s Cancer Biology Institute. The study’s first authors were Keshav Patil, a graduate student in Penn Engineering’s Department of Chemical and Biomolecular Engineering, along with Earl Joseph Jordan and Jin H. Park, then members of the Graduate Group in Biochemistry and Molecular Biology in Penn’s Perelman School of Medicine. Krishna Suresh, an undergraduate student in Radhakrishnan’s lab, Courtney M. Smith, a graduate student in Lemmon’s lab, and Abigail A. Lemmon, an undergraduate in Lemmon’s lab, contributed to the study. They collaborated with Yaël P. Mossé, Associate Professor of Pediatrics at Penn Medicine and in the division of oncology at CHOP.

“Some cancers rely on the aberrant activation of a single gene product for tumor initiation and progression,” says Radhakrishnan. “This unique mutational signature may hold the key to understanding which patients suffer from aggressive forms of the disease or for whom a given therapeutic drug may yield short- or long-term benefits. Yet, outside of a few commonly occurring ‘hotspot’ mutations, experimental studies of clinically observed mutations are not commonly pursued.”

Read the full post in Penn Engineering Today.

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BE Seminar: “Deciphering the Dynamics of the Unconscious Brain Under General Anesthesia” (Emery Brown)

Emery Brown, MD, PhD

Speaker: Emery N. Brown, MD, PhD
Edward Hood Taplin Professor of Medical Engineering and of Computational Neuroscience, MIT
Warren M. Zapol Professor of Anaesthesia, Harvard Medical School
Massachusetts General Hospital

Date: Thursday, April 1, 2021
Time: 3:00-4:00 PM EDT
Zoom – check email for link or contact ksas@seas.upenn.edu

Title: “Deciphering the Dynamics of the Unconscious Brain Under General Anesthesia”

Abstract:

General anesthesia is a drug induced state that is critical for safely and humanely allowing a patient to undergo surgery or an invasive diagnostic procedure. During the last 10 years the study of the neuroscience of anesthetic drugs has been an active area of research. In this lecture we show how anesthetics create altered states of arousal by creating oscillation that impede how the various parts of the brain communicate. These oscillations, which are readily visible on the electroencephalogram (EEG), change systematically with anesthetic dose, anesthetic class and patient age. We will show how the EEG oscillations can be used to monitor the brain states of patients receiving general anesthesia, manage anesthetic delivery and learn about fundamental brain physiology.

EMERY BROWN BIO:

Emery N. Brown is the Edward Hood Taplin Professor of Medical Engineering and Professor of Computational Neuroscience at Massachusetts Institute of Technology. He is the Warren M. Zapol Professor of Anaesthesia at Harvard Medical School and Massachusetts General Hospital (MGH), and an anesthesiologist at MGH.

Dr. Brown received his BA (magna cum laude) in Applied Mathematics from Harvard College, his MA and PhD in statistics from Harvard University, and his MD (magna cum laude) from Harvard Medical School. He completed his internship in internal medicine at the Brigham and Women’s Hospital and his residency in anesthesiology at MGH. He joined the staff at MGH, the faculty at Harvard Medical School in 1992 and the faculty at MIT in 2005.

Dr. Brown is an anesthesiologist-statistician recognized for developing signal processing algorithms for neuroscience data analysis and for defining the neurophysiological mechanisms of general anesthesia.

Dr. Brown was a member of the NIH BRAIN Initiative Working Group. He is a fellow of the IEEE, the AAAS, the American Academy of Arts and Sciences and the National Academy of Inventors. Dr. Brown is a member of the National Academy of Medicine, the National Academy of Sciences and the National Academy of Engineering. He received an NIH Director’s Pioneer Award, the National Institute of Statistical Sciences Sacks Award, the American Society of Anesthesiologists Excellence in Research Award, the Dickson Prize in Science, the Swartz Prize for Theoretical and Computational Neuroscience and a Doctor of Science (honoris causa) from the University of Southern California.

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Hao Huang Named AIMBE Fellow

Hao Huang, Ph.D.

Hao Huang, Research Associate Professor of Radiology in the Perelman School of Medicine and member of the Penn Bioengineering Graduate Group, has been named an American Institute for Medical and Biological Engineering (AIMBE) Fellow.

Election to the AIMBE College of Fellows is among the highest professional distinctions accorded to a medical and biological engineer. “The College of Fellows is comprised of the top two percent of medical and biological engineers in the country. The most accomplished and distinguished engineering and medical school chairs, research directors, professors, innovators, and successful entrepreneurs comprise the College of Fellows. AIMBE Fellows are regularly recognized for their contributions in teaching, research, and innovation.”

Huang was “nominated, reviewed, and elected by peers and members of the College of Fellows for contributions to the development and applications of innovative MR methods to study the developing brain.”

A formal induction ceremony will be held during AIMBE’s virtual 2021 Annual Event on March 26. Huang will be inducted along with 174 colleagues who make up the AIMBE Fellow Class of 2021.

Read the full press release.

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Penn Alumnus Peter Huwe Appointed Assistant Professor at Mercer University

Peter Huwe, Ph.D.

Peter Huwe, a University of Pennsylvania alumnus and graduate of the Radhakrishnan lab, was appointed Assistant Professor of Biomedical Sciences at the Mercer University School of Medicine beginning this summer 2020 semester.

Huwe earned dual B.S. degrees in Biology and Chemistry in 2009 from Mississippi College, where he was inducted into the Hall of Fame. At Mississippi College, Huwe had his first exposure to computational research in the laboratory of David Magers, Professor of Chemistry and Biochemistry. He went on to earn his Ph.D. in Biochemistry and Molecular Biophysics in 2014 in the laboratory of Ravi Radhakrishnan, Chair of the Bioengineering Department at Penn. As an NSF Graduate Research Fellow in Radhakrishnan’s lab, Huwe focused his research on using computational molecular modeling and simulations to elucidate the functional consequences of protein mutations associated with human diseases. Dr. Huwe then joined the structural bioinformatics laboratory Roland Dunbrack, Jr., Professor at the Fox Chase Cancer Center as a T32 post-doctoral trainee. During his post-doctoral training, Huwe held adjunct teaching appointments at Thomas Jefferson University and at the University of Pennsylvania. In 2017, Huwe became an Assistant Professor of Biology at Temple University, where he taught medical biochemistry, medical genetics, cancer biology, and several other subjects.

During each of his appointments, Huwe became increasingly more passionate about teaching, and he decided to dedicate his career to medical education. Huwe is very excited to be joining Mercer University School of Medicine as an Assistant Professor of Biomedical Sciences this summer. There, he will serve in a medical educator track, primarily teaching first and second year medical students.

“Without Ravi Radhakrishnan and Philip Rea, Professor of Biology in Penn’s School of Arts & Sciences, giving me my first teaching opportunities as a graduate guest lecturer at Penn, I may never have discovered how much I love teaching,” says Huwe. “And without the support and guidance of each of my P.I.’s [Dr.’s Magers, Radhakrishnan, and Dunbrack], I certainly would not be where I am, doing what I love.  I am incredibly thankful for all of the people who helped me in my journey to find my dream job.”

Congratulations and best of luck from everyone in Penn Bioengineering, Dr. Huwe!

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Week in BioE (July 31, 2018)

New Data Analysis Methods

Like many other fields, biomedical research is experiencing a data explosion. Some estimates suggest that the amount of data generated from the health sciences is now doubling every eighteen months, and experts expect it to double every seventy-three days by 2020.  One challenge that researchers face is how to meaningfully analyze this data tsunami.

The challenge of interpreting data occurs at all scales, and a recent collaboration shows how new approaches can allow us to handle the volumes of data emerging at the level of individual cells to infer more about how biology “works” at this level.  Wharton Statistics Department researchers Mo Huang and Jingshu Wang (PhD Student and Postdoctoral Researcher, respectively) collaborated with Arjun Raj’s lab in Bioengineering and published their findings in recent issues of Nature Methods and Proceedings of the National Academy of Sciences.  One study focused on a de-noising technique called SAVER to provide more precise data from single cell experiments and significantly improves the ability to detect trends in a dataset, similar to how increasing sample size helps improve the ability to determine differences between experimental groups.  The second method, termed DESCEND, creates more accurate characterization of gene expression that occur in individual cells. Together these two methods will improve data collection for biologists and medical professionals working  to diagnose, monitor, and treat diseased cells.

Dr. Raj’s team contributed data to the cause and acted as consultants on the biological aspects of this research. Further collaboration involved Mingyao Li, PhD, Professor of Biostatistics at the Perelman School of Medicine, and Nancy Zhang, PD, Professor Statistics at the Wharton School. “We are so happy to have had the chance to work with Nancy and Mingyao on analyzing single cell data,” said Dr. Raj. “The things they were able to do with our data are pretty amazing and important for the field.”

Advancements in Biomaterials

This blog features many new biomaterials techniques and substances, and there are several exciting new developments to report this week. First, the journal of Nature Biomedical Engineering published a study announcing a new therapy to treat or even eliminate lung infections, such as those acquired while in hospital or as the result of cystic fibrosis, which are highly common and dangerous. Researchers identified and designed viruses to target and kill the bacteria which causes these infections, but the difficulty of administering them to patients has proven prohibitive. This new therapy, developed by researchers at the Georgia Institute of Technology, is administered as a dry powder directly to the lungs and bypasses many of the delivery problems appearing in past treatments. Further research on the safety of this method is required before clinical trials can begin.

A team at Harvard University published another recent study in Nature Biomedical Engineering announcing their creation of a tissue-engineered scale model of the left human heart ventricle. This model is made from degradable fibers that simulate the natural fibers of heart tissue. Lead investigator Professor Kevin Kit Parker, PhD, and his team eventually hope to build specific models culled from patient stem cells to replicate the features of that patient’s heart, complete with the patient’s unique DNA and any heart defects or diseases. This replica would allow researchers and clinicians to study and test various treatments before applying them to a specific patient.

Lastly, researchers at the Tufts University School of Engineering published in the Proceedings of the National Academy of Sciences on their creation of flexible magnetic composites that respond to light. This material is capable of macroscale motion and is extremely flexible, allowing its adaptation into a variety of substances such as sponges, film, and hydrogels. Author and graduate student Meg Li explained that this material differs from similar substances in its complexity; for example, in the ability for engineers to dictate specific movements, such as toward or away from the light source. Co-author Fiorenzo Omenetto, PhD, suggests that with further research, these movements could be controlled at even more specific and detailed levels.

CFPS: Getting Closer to “On Demand” Medicine

A recent and growing trend in medicine is the move towards personalized or “on demand” medicine, allowing for treatment customized to specific patients’ needs and situations. One leading method is Cell-Free Protein Synthesis (CFPS), a way of engineering cellular biology without using actual cells. CFPS is used to make substances such as medicine, vaccines, and chemicals in a sustainable and portable way. One instance if the rapid manufacture of insulin to treat diabetic patients. Given that many clinics most in need of such substances are found in remote and under-served locations far away from well-equipped hospitals and urban infrastructure, the ability to safely and quickly create and transport these vital substances to patients is vitally important.

The biggest limiting factor to CFPS is difficulty of replicating Glycosylation, a complex modification that most proteins undergo. Glycosylation is important for proteins to exert their biological function, and is very difficult to synthetically duplicate. Previously, achieving successful Glycosylation was a key barrier in CFPS. Fortunately, Matthew DeLisa, PhD, the Williams L. Lewis Professor of Engineering at Cornell University and Michael Jewett, PD, Associate Professor of Chemical and Biological Engineering at Northwestern University, have created a “single-pot” glycoprotein biosynthesis that allows them to make these critical molecules very quickly. The full study was recently published in Nature Communications. With this new method, medicine is one step closer to being fully “on demand.”

People and Places

The Institute of Electrical and Electronics Engineers (IEEE) interviewed our own Penn faculty member Danielle Bassett, PhD, the Edwardo D. Glandt Faculty Fellow and Associate Professor in Bioengineering, for their website. Dr. Bassett, who shares a joint appointment with Electrical Systems Engineering (ESE) at Penn, has published groundbreaking research in Network Neuroscience, Complex Systems, and more. In the video interview (below), Dr. Bassett discusses current research trends in neuroscience and their applications in medicine.

Finally, a new partnership between Case Western Reserve University and Cleveland Clinic seeks to promote education and research in biomedical engineering in the Cleveland area. Cleveland Clinic Lerner Research Institute‘s Chair of Biomedical Engineering, Geoff Vince, PhD, sees this as an opportunity to capitalize on the renown of both institutions, building on the region’s already stellar reputation in the field of BME. Dozens of researchers from both institutions will have the opportunity to collaborate in a variety of disciplines and projects. In addition to professional academics and medical doctors, the leaders of this new partnership hope to create an atmosphere that can benefit all levels of education, all the way down to high school students.

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Week in BioE (September 1, 2017)

Overcoming CP With Robotics

robotic exoskeletonCerebral palsy (CP) remains one of the most common congenital birth defects, affecting 500,000 American newborns per year. Gait disorders from CP are common, and crouch gait — characterized by misdirection and improper bending of the feet, causing excessive knee bending and the appearance of crouching — is among the most difficult to correct.

Researchers at Northern Arizona University recently developed a new exoskeleton to treat crouch gait. In an article published in Science Translational Medicine, Zach Lerner, Ph.D., assistant professor of mechanical engineering and a faculty member with NAU’s Center for Bioengineering Innovation, tested a robotic, motorized exoskeleton in seven patients with crouch gait. Six of the seven participants using the exoskeleton show improvements on par with surgical procedures to correct crouch gait. Although commercial availability of the exoskeleton will require testing in much larger patient groups, the device is an encouraging development in the treatment of a difficult disorder.

Brain Science News

A couple of weeks ago, we discussed here how the Department of Defense supports research using electrical stimulation of the scalp to direct brain activity. At the University of Texas at Arlington (UTA), bioengineering professor Hanli Liu, Ph.D., received a NIH grant to test how infrared light, rather than electrical stimulation, can achieve similar effects on the brain. In collaboration with two other UTA professors, Professor Liu uses Transcranial Infrafred Brain Stimulation (TIBS) to project infrared light onto the forehead to enhance blood flow and oxygen supply to the underlying area of the brain. With the grant, she and her colleagues intend to develop imaging tools that will provide greater insight into how both TIBS and the brain itself work.

Even as we learn more about the brain, the devastating effects of neurodegenerative diseases show us how much we still don’t know. Certain drugs can slow the inevitable advance of the disease, but beginning treatment early is important to maintaining a sense of normalcy. At Case Western Reserve University, Anant Madabhushi, Ph.D., professor of biomedical engineering, is developing computer technology to distinguish Alzheimer’s from other disorders and to predict onset earlier and more accurately.  Reporting their outcomes in Scientific Reports from testing in nearly 150 patients, Dr. Madabhushi and his colleagues used a variety of clinical measures (blood biomarkers, imaging data, neuropsychological testing) instead of a single test and developed a much more accurate test for detecting Alzheimer’s disease. Their approach, called cascaded multiview canonical correlation (CaMCCo), used the ordered analysis of different tests to stratify different patient groups at each stage, rather than developing a single combined measure all at once. More work will be needed to determine how this approach can lead to earlier detection of Alzheimer’s, but its accuracy is very encouraging for future studies.

Causes for Congratulations

Rose-Hulman Institute of Technology has announced that Kay C. Dee, Ph.D., is among the recipients of this year’s Inspiring Leaders in STEM Award from Insight Into Diversity magazine.  Professor Dee, Associate Dean of Learning and Technology and Professor of Biology and Biomedical Engineering at Rose-Hulman, is the former head of her department. As a dean, she has focused on several issues, including easier access for students with disabilities. Congratulations to Dr. Dee!

Also, several bioengineering and biomedical engineering departments across the country are celebrating birthdays. The departments at both the University of Virginia (biomedical engineering) and the University of Michigan (bioengineering) are 50 years old, with Michigan also celebrating the 20th birthday of their biomedical engineering department. The comparative baby of the group, the Department of Biomedical Engineering at Tulane University, turns 40. Happy birthday all!