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Charles J. Homcy and Simeon G. Margolis Professorship

School of Medicine

Established in 2016 by Charles Homcy in honor of Simeon Margolis


SIMEON G. MARGOLIS, MD, PhD, received his bachelors, medical, and doctorate degrees from The Johns Hopkins University. After completing his internship and residency at Johns Hopkins Hospital in 1965, he was appointed as an Assistant Professor in Medicine. He is currently Professor Emeritus of Medicine and Biological Chemistry at the Johns Hopkins University School of Medicine. Dr. Margolis’ research has centered in the laboratory on the control of cholesterol metabolism as well as in clinical studies in regulation of blood glucose levels. He was the Director of the Division of Endocrinology and Metabolism in the Department of Medicine from 1968 to 1981 and from 1985 to 1990. He served as the Associate Dean for Academic Affairs at Johns Hopkins from 1984 to 1990 and subsequently was Associate Dean for Faculty Affairs for 18 months.

Dr. Margolis has been a member of various committees for the Department of Health, Education, and Welfare, including the Metabolism Study Section, General Clinical Research Centers, National Diabetes Advisory Board, and the Arteriosclerosis Specialized Centers of Research Review Committees. In addition, he has acted as a member of the Endocrinology and Metabolism Panel of the US Food and Drug Administration.

A former weekly columnist for The Baltimore Sun, Dr. Margolis has served for more than 20 years as Medical Editor of The Johns Hopkins Medical Letter: Health After 50. Dr. Margolis has lectured to medical students, physicians, and the general public on a wide variety of topics, such as the prevention of coronary heart disease, the control of cholesterol levels, the treatment of diabetes, and “alternative medicine.” He has also written numerous white papers for Johns Hopkins on a wide variety of medical topics. For the past four years, Dr. Margolis has had regular blogs on Yahoo! Health.

Held by Alex L. Kolodkin

Brian Institute

Dr. ALEX L. KOLODKIN is a professor in the Department of Neuroscience at the Johns Hopkins University School of Medicine. He received his PhD in molecular biology from the University of Oregon at Eugene in 1987, under the mentorship of Dr. Franklin W. Stahl, and completed a postdoctoral fellowship at The University of California at Berkeley, working with Dr. Corey S. Goodman. He came to the Johns Hopkins University School of Medicine in 1995 and was promoted to full professor in 2004. Since 2005, he has been an investigator of the Howard Hughes Medical Institute. He was elected to the American Association for the Advancement of Science in 2014, and elected to the American Academy of Arts and Sciences in 2016. He also received the Pradel research Award of the National Academy of Sciences in 2016.

Dr. Kolodkin studies how neurons in the brain are wired up during development. He and his colleagues have identified molecular cues that guide neurons to their appropriate targets and that also promote the formation of synaptic connections critical for normal circuit function. Dr. Kolodkin led in the discovery of one of the largest family of phylogenetically conserved neuronal guidance cues, the semaphorins, and here at Hopkins he identified the first neuronal semaphorin receptor. His team has shown how semaphorins and their receptors direct neuronal connectivity in multiple neural systems. They have also shown that classical guidance cues and their receptors function to regulate excitatory synaptogenesis in the mammalian brain. Recent work in his laboratory identifies key guidance cues and receptors that orchestrate connectivity in the mammalian retina and that regulate for formation of retinal neuron axon connections to the brain. Together, his work provides a framework for understanding how a limited number of guidance molecules is capable of sculpting, maintaining, and refining complex neural circuitry.