McCormick School of Engineering, Northwestern University

Abstract:

Work in our laboratory aims to understand how tactile information is encoded and processed in the early stages of the nervous system. We use the rat whisker system as a model because the neural processing pathways are analogous to human tactile pathways through the spinal cord and because whiskers are relatively easy to observe and manipulate.

Rats are nocturnal, burrowing animals with poor vision. To tactually explore the world, rats brush their whiskers rhythmically against objects between 5 and 25 times per second. Using only its whiskers, a rat can determine an object's size, shape, orientation, and texture. About 30 whiskers are arranged in a regular array on each side of the rat’s face. The base of each whisker is embedded within a densely innervated follicle where mechanoreceptors transduce deformations to electrical signals and provide input to the brain.

This talk will consist of two parts. In the first, I will describe recent advances our laboratory has made in understanding how rats explore objects with their whiskers, and steps we are taking to understand how the nervous system processes this tactile information. In the second, I will describe some possible applications of tactile sensing with whiskers.

Instead of presenting "conclusions" of the talk, I will raise a series of questions to inspire brainstorming and discussion with the audience, with the aim of finding new - possibly clinically relevant - applications. It will be particularly interesting to work with the audience to determine whether there may be clinical applications based on ideas our laboratory has about how the nervous system processes information.

Biosketch:

Prof. Mitra J. Hartmann received a Bachelor of Science in Applied and Engineering Physics from Cornell University, and a PhD in Integrative Neuroscience from the California Institute of Technology. From 2000 - 2003 she was a postdoctoral scholar in the Bio-Inspired Technology and Systems group at the Jet Propulsion Laboratory in Pasadena, California. Prof. Hartmann joined the faculty at Northwestern University in 2003 and is presently an Associate Professor with a 50-50 joint appointment between the departments of Biomedical Engineering and Mechanical Engineering. She is also a member of Northwestern's Interdepartmental Neuroscience Program (NUIN).

Abstract:

As Americans age and the acute mortality from cardiovascular disease-otherwise known as heart disease- decreases, a large group of patients is emerging who have chronic cardiovascular disease. Many of these patients remain severely symptomatic and cannot be helped by traditional medical treatments such as angioplasty, bypass surgery, and stents. Currently, no treatments exist that directly address the needs of these patients.

Dr. Losordo’s lecture, the second in the “Dean’s Grand Challenges in Medicine and Engineering” series, will discuss a promising new approach to therapy for this group using stem cells for ischemic tissue repair.

Mounting evidence suggests microvascular insufficiency, that is, disease of the very small vessels, plays a significant role in the overall loss of blood supply to tissues. This lack of blood supply is called “ischemia.” Early studies indicate that a variety of growth factors and stem/progenitor cells may be used for repair of ischemic tissue.

Dr. Losordo’s lecture will share results from early studies documenting a potentially potent treatment using endothelial progenitor cells(EPC) which show ischemic tissue repair appears feasible for testing in human clinical trials.

He will also share the results of his own phase II randomized controlled trial that reveal injection of a patient’s own stem cells-EPCs- directly into areas of decreased blood supply in the heart muscle led to reduced chest pain, improved exercise capacity and a reduction in adverse safety outcomes.

The evolution of the strategy of ischemic tissue repair will require an ongoing dialogue between clinicians, scientists, regulators, and industry to take full advantage of advances in our understanding of the biology of these processes and their appropriate application to patients. Dr. Losordo’s lecture is one step further in opening the dialogue.

Bio:

Douglas W. Losordo, MD is the director of the Feinberg Cardiovascular Research Institute and the Eileen M. Foell Professor of Heart Research at Northwestern University's Feinberg School of Medicine and director of the Program in Cardiovascular Regenerative Medicine at Northwestern Memorial Hospital. He is board-certified in internal medicine, cardiovascular disease, and interventional cardiology and is a fellow of the American College of Cardiology, the American Heart Association, the American Association for the Advancement of Science, the American College of Physicians, the American College of Chest Physicians, and the Society for Cardiac Angiography and Interventions.

Dr. Losordo‘s major research interests encompass angiogenesis/ vasculogenesis, progenitor/adult stem cells, tissue repair/regeneration, and vascular biology. A native of New York City, he received his medical degree from the University of Vermont. Dr. Losordo completed an internship, residency and fellowship at St. Elizabeth’s Medical, Boston, Massachusetts where he subsequently joined the faculty, working with the late Jeff Isner to develop a program in therapeutic angiogenesis and cell based tissue repair. Dr. Losordo‘s group has executed the full “translational medicine” paradigm, identifying novel therapeutics in the laboratory, developing these strategies in small and large animal models and designing and executing first in human clinical trials. Examples include VEGF gene therapy for myocardial ischemia and diabetic neuropathy, and CD34+ cell therapy for refractory angina and severe claudication. Dr. Losordo has also trained numerous scientists and physician scientists from around the world.

Abstract:

Many biological organisms rely on adhesion to surfaces for their very survival, often implementing elegant and creative solutions that are finely tuned to local environments. Marine mussels, for example, have evolved sophisticated protein glues that robustly attach to rocks and man-made structures such as piers and ship hulls. The proteins found in these glues have very specialized amino acid compositions, undoubtedly related to the particular challenges of achieving permanent adhesion in the wet marine environment. In stark contrast, geckos exploit temporary adhesion for the purposes of locomotion in largely dry environments. Although adhesion in this case is also mediated by protein in the form of dense arrays of very fine foot hairs, the proteins are of rather ordinary composition (keratin) and adhesive forces arise from weak transient chemical forces between the tips of foot-hairs and opposing surfaces. This approach only works in dry environments.

In this talk I will focus on these two remarkable but contrasting adhesive strategies, and the opportunities that exist for exploiting key features of these approaches to solve medical problems. Basic biophysical and chemical studies are enhancing our understanding of the molecular aspects of biological adhesion and inform the design of novel medical materials useful as surgical adhesives and sealants, and as coatings of medical devices.

Bio:

Phillip B. Messersmith, PhD, is a professor of Biomedical Engineering, Materials Science and Engineering and Chemical and Biological Engineering at Northwestern University. He earned his B.S. degree in life sciences in 1985 and his Ph.D. degree in materials science and engineering in 1993, both from the University of Illinois at Urbana. Before coming to Northwestern University, Dr. Messersmith was a postdoctoral fellow at Cornell University, and was a faculty member at the University of Illinois at Chicago (1994-1997). His research interests include biological adhesion, bioinspired synthesis of materials, polymeric biomaterials, regenerative medicine, biomineralization, self-assembly and nanostructured materials. Current research projects include studies of biological adhesives, including mussel adhesive proteins and gecko adhesives, the design of biomimetic adhesive polymers and polymer composites, development of novel biomaterials for regenerative medicine, and antifouling polymer surfaces. His awards and honors include a young investigator award from the Whitaker Foundation, a MERIT award from the NIH, and the Langmuir Lecture Award from the American Chemical Society. Dr. Messersmith is a fellow of the American Institute for Medical and Biological Engineering and a member of the editorial boards of Soft Matter, Nanomedicine, Biointerphases and Biomedical Materials.