‘For Neurodegeneration, a Different Way to Slice the Pie’

Danielle Bassett, Ph.D.

Danielle Bassett, J. Peter Skirkanich Professor in the departments of Bioengineering and Electrical and Systems Engineering, has been called the “doyenne of network neuroscience.” The burgeoning field applies insights from the field of network science, which studies how the structure of networks relate to their performance, to the billions of neuronal connections that make up the brain.

Much of Basset’s research draws on mathematical and engineering principles to better understand how mental traits arise, but also applies them more broadly to other challenges in neuroscience.

In her latest paper, “Defining and predicting transdiagnostic categories of neurodegenerative disease,” published in the journal Nature Biomedical Engineering, Bassett collaborated with the Perelman School of Medicine’s Virginia Man-Yee Lee and John Trojanowski to provide a new perspective on the misfolded proteins associated with those diseases.

The researchers used machine learning techniques to create a new classification system for neurodegenerative diseases, one which may redraw the boundaries between them and help explain clinical differences in patients who received the same diagnoses.

BioWorld’s Anette Breindl spoke with Bassett about the team’s findings.

Now, investigators have developed a new approach to classifying neurodegenerative disorders that used the overall patterns of protein aggregation, rather than specific proteins, to define six clusters of patients that crossed traditional diagnostic categories.

“We find that perhaps the way that clinicians have been diagnosing these disorders… is not necessarily the way these disorders work,” Danielle Bassett told BioWorld. “The way we’ve been trying to carve nature at joints is not the way that nature has joints. The joints are elsewhere.”

Continue reading Breindl’s article, “For neurodegeneration, a different way to slice the pie,” at BioWorld.

Originally posted on the Penn Engineering blog. Media contact Evan Lerner.

Week in BioE (June 28, 2019)

by Sophie Burkholder

Innovations in Vascularization Could Lead to a New Future in Bioprinting

We may be one step closer to 3D-printing organs for transplants thanks to innovations in vascularization from researchers at Rice University and Washington University. Jordan Miller, Ph.D., a Penn Bioengineering alumnus, now an assistant professor of bioengineering at Rice, worked with his colleague Kelly Stevens, Ph.D., an assistant professor of the bioengineering department at Washington, to develop 3D-printed networks that mimicked the vascularized pathways for the transport of blood, lymph, and other fluids in the body. Their work appeared on a recent cover of Science, featuring a visual representation of the 3D-printed vessels in vasculature meant to mirror that of the human lung.

Relying heavily on open source 3D-printing, Miller and Stevens, along with collaborators from a handful of other institutions and start-ups, found ways to model dynamic vasculature systems similar to heart valves, airways systems, and bile ducts to keep 3D-printed tissue viable. The video below demonstrates the way the team successfully modeled vasculature in a small portion of the lung by designing a net-like structure around a sack of air. But Miller, a long-time supporter of open source printing and bioprinting, hopes that this is merely one step closer to what he sees as the ultimate goal of allowing for all organs to be bioprinted. Having that sort of power would reduce the complex issues that come with organ transplants, from organ availability to compatibility, and bring an end to a health issue that affects the over 100,000 people on the organ transplant waiting list.

A Combination of Protein Synthesis and Spectrometry Improve Cell Engineering

One goal of modern medicine is to create individualized therapeutics by figuring out a way to control cell function to perform specific tasks for the body without disrupting normal cell function. Balancing these two goals often proves to be one of the greatest difficulties of this endeavor in the lab, but researchers at Northwestern University found a way to combine the two functions at once in methods they’re calling cell-free protein synthesis and self-assembled monolayer desorption ionization (SAMDI) mass spectrometry. This innovation in the combination of the two methods accelerates the trial and error process that comes with engineering cells for a specific need, allowing researchers to cover a lot more ground in determining what works best in a smaller amount of time.

Leading the study are Milan Mrksich, Ph.D., a Henry Wade Rogers Professor of Biomedical Engineering at Northwestern, and Michael Jewett, Ph.D., a Charles Deering McCormick Professor of Teaching Excellence and co-director of the Center for Synthetic Biology at Northwestern. Together, they hope to continue to take advantage of the factory-like qualities of cell operations in order to use cells from any organisms to our advantage as needed. By helping to reduce the amount of time spent on trial and error, this study brings us one step closer to a world of efficient and individualized medicine.

Non-Invasive Sensory Stimulation as New Way of Treating Alzheimer’s

What if we could reduce the effects of Alzheimer’s disease with a non-invasive therapy comprised of only sensory inputs of light and sound? A recent study between Georgia Tech and MIT tries to make that possible. Alzheimer’s patients often have a larger than normal number of amyloid plaques in their brains, which is a naturally occurring protein that in excess can disrupt neurological function. The treatment —  designed in part by Abigail Paulson, a graduate student in the lab of Annabelle Singer, Ph.D., assistant professor of Biomedical Engineering at Georgia Tech and Emory University — uses a combination of light and sound to induce gamma oscillations in brain waves of mice with high amounts of these amyloid plaques. Another lead author of the study is Anthony Martorell, a graduate student in the Tsai Lab at MIT, where Singer was a postdoctoral researcher.

This new approach is different from other non-invasive brain therapies for memory improvement, as tests demonstrated that it had the power to not only reach the visual cortex, but that it also had an effect on the memory centers in the hippocampus. An innovation like this could bring about a more widespread form of treatment for Alzheimer’s patients, as the lack of a need for surgery makes it far more accessible. Singer hopes to continue the project in the future by looking at how these sensory stimulations affect the brain throughout a variety of processes, and more importantly, if the therapy can be successfully applied to human patients.

NIH Grant Awarded to Marquette Biomedical Engineering Professor for Metal Artifact Reduction Techniques in CT Scans

Taly Gilat-Shmidt, Ph.D., an associate professor of biomedical engineering at Marquette University, recently received a $1.4 million grant from the National Institute of Health to improve methods for radiation treatment through metal artifact reduction techniques. When patients have some sort of metal that can’t be removed, such as an orthopaedic implant like a hip or knee replacement, it can interfere with the imaging process for CT scans and lead to inaccuracies by obscuring some tissue in the final images. These inaccuracies can lead to difficulty in devising treatment plans for patients who require radiation, as CT scans are often used to assess patients and determine which line of treatment is most appropriate. Gilat-Schmidt hopes to use the grant to implement tested algorithms to help reduce this variability in imaging that comes from metal implants.

People and Places

Activities for Community Education in Science (ACES), founded by Penn chemistry graduate students in 2014, aims to inspire interest and provide a positive outlook in STEM for kids and their families. The biannual event provides students grades 3–8 with an afternoon of demonstrations, experiments, and hands-on activities focused on physics and chemistry.

After an explosive opening demonstration, more than 70 students made their way between experiments in small groups, each participating in different experiments based on their age.

Read the rest of this story on Penn Today.

The Society of Women Engineers (SWE) is a non-profit organization serving as one of the world’s largest advocates for women in engineering and technology over the past six decades. With a mission to empower women to become the next leading engineers of the world, SWE is just one of many agents hoping to bring more diversity to the field. Our chapter of SWE at Penn focuses particularly on professional development, local educational outreach, and social activities across all general body members. In a new article from SWE Magazine, the organization collected social media responses from the public on the women engineers we should all know. With a diverse list of engineers from both the past and present, the article helps bring to light just how much even a handful of women contributed to the field of engineering already.

 

Week in BioE (December 8, 2017)

Brain Implant Advance to Cure Dementia

Alzheimer's
Neurofibrillary tangles in the hippocampus of a patient with Alzheimer’s disease.

The dramatic increase in life expectancy over the past couple of generations has one unfavorable consequence: an increase in the incidence of age-related dementias that include Alzheimer’s disease. Drugs like donepezil, which inhibits hydrolization of acetylcholine and thus increases its presence at the neural synapses, is one treatment that can slow the progression of these diseases, but there is currently no cure. 

An alternative technology that directly stimulates the brain with an implantable chip holds promise to reverse the effects of Alzheimer’s. At the annual meeting of the Society for Neuroscience, held last month in Washington, D.C., Dong Song, Ph.D., Research Associate Professor of Biomedical Engineering at USC’s Viterbi School of Engineering, gave a lecture on his lab’s device, which uses an array of implantable electrodes to improve human memory.

Dr. Song tested his device in epilepsy patients, who often receive implants designed to control their seizures in intractable cases. Twenty such patients volunteered to receive Dr. Song’s implant, and data from these patients showed that short-term memory increased by 15% and working memory by 25%. While additional testing is needed on more patients, it might not be long before implants like Dr. Song’s become the standard of care in treatment dementias.

Genetic Variation in the Human Microbiome

The human body is host to a veritable universe of microbes that play important roles in the organ systems and other bodily processes. E. coli, for example, is present in the large intestine and it participates in the breaking down of food for energy. Like all other forms of life, these microbes evolve. creating variations in genetic information and, ultimately, new bacteria species. Within any given species of bacteria, the number of differences in the genome sequences can vary broadly; with E. coli, some areas of the genome can vary radically between strains and cannot be explained by DNA copying errors.
   
To determine why the genome of E. coli subject to such variation, scientists at the University of Illinois, Urbana-Champaign (UIUC), led by Sergei Maslov, Ph.D., professor of bioengineering and physics at UIUC, investigated the issue by developing computational models using Multi Locus Sequence Typing (MLST). In their findings, published in Genetics, they concluded that the variation can be ascribed to the process of recombination, by which different sequences from different sources are combined into the same chromosome. When such events are frequent, they result in a sort of genetic stability in which variation in genetic information increases without speciation.

The study provides an important contribution to basic science in helping to better explain how different strains of bacteria develop, including virulent and drug-resistant strains. In addition, it sheds further light on the mechanisms underlying evolution.

A Step Closer to Water-efficient Agriculture

Drought and famine are closely related phenomena. Some plants are more resistant to drought than others, but few of these plants are fit for human consumption. Determining how plants resist drought could provide a key to engineering crops to become drought-resistant.
Investigating this topic, scientists at the Oak Ridge National Laboratory of the U.S. Department of Energy sought to understand better the process of crassulacean acid metabolism (CAM), by which drought-resistant plants keep their stomata, or pores, closed during sunlight hours to retain water and open them at night. The team reports in Nature Communications that they compared the genomes of three drought-resistant plants — orchid, pineapple, and Kalanchoë fedtschenkoi, a species of plant native to Madagascar.  Among the authors’ discoveries was a variation in a gene encoding phosphoenolpyruvate carboxylase, an enzyme that plays a role in CAM.

With this increased knowledge of the evolutionary development of drought resistance, we come a step closer to being able to expedite the evolution of plants that are typically not resistant to drought to developing the CAM mechanism and developing this resistance.

Computer Model Can Mimic Heart Attack

Heart disease remains the leading cause of death in developed countries. A major obstacle in reducing the deaths due to cardiac arrest is the inability to determine the precise mechanics unfolding in the heart when it stops suddenly. Abnormal heart rhythms (arrythmias) are a major cause of death, but the reasons how arrhythmias occur at the cellular level is poorly understood.

In a recent study published in PLOS Computational Biology,  Raimond L. Winslow, Ph.D. who is Raj and Neera Singh Professor in the Department of Biomedical Engineering at Johns Hopkins University, and his colleagues developed a computer model of calcium dynamics in cardiac cells. The model predicted a new mechanism for arrythmia that would occur when cardiac cells expelled calcium, creating an electrical charge outside the cell that could evoke an arrhythmia.

The authors believe that their research will facilitate the development of drugs to prevent cardiac arrhythmias and treatments for sudden cardiac arrest. In addition, the work shows that it could be easier to predict the statistical relationship between arrhythmias and cardiac arrest on the basis of far less data.

People and Places

Stevens Institute of Technology in Hoboken, N.J., has announced plans to divide its Department of Biomedical Engineering, Chemistry and Biological Sciences (BCB) into two new departments: the Department of Biomedical Engineering and the Department of Chemistry and Chemical Biology. Hongjun Wang, Ph.D., associate professor in the BCB department, will be the new chair of BME. Congratulations Hongjun!