The Block Center Physicians
R. Deva Nathan, M.D., has worked with the Block Medical Team for over ten years. Dr. Nathan is board certified in Internal Medicine, Hematology, and Oncology. He serves on the faculty of Midwestern University's College of Osteopathic Medicine. He completed his residency at the Medical College of Pennsylvania & Veterans Administration Hospital in Philadelphia and received fellowships in both Clinical Pathology at the Albert Einstein Medical Center in Philadelphia and in Hematology-Oncology at the University of Illinois Medical Center & Veterans Administration Hospital in Chicago. Dr. Nathan is a member of the American Society of Clinical Oncology, American Society of Hematology, Illinois Cancer Council, Eastern Cooperative Oncology Group, Chicago Medical Society, Illinois Medical Society, American Medical Association, and the American Federation for Clinical Research.
Michael De La Torre, M.D., joined the Block Center in 1997, after positions as a surgical clinician in Maryland, a multi-specialty internist for Victory Memorial Hospital in Waukegan, Illinois, and a volunteer physician helping medically underserved communities in greater Chicago. Dr. De La Torre is board certified in Internal Medicine and is a member of the American College of Physicians, American Medical Association and the Chicago Medical Society.
Physician's Assistants
Jennifer Ellis, PA-C., joined Block Center as a Physician Assistant in the summer of 2000. She is a graduate of DePauw University, as well as Midwestern University's Physician Assistant program, from which she graduated magna cum laude. She has taken coursework and completed continuing education to specialize in Oncology.  She is a fully licensed Physician Assistant in the state of Illinois and an adjunct staff member of St. Francis Hospital in Evanston, Illinois. A member of Phi Beta Kappa, she also belongs to the American Academy of Physician Assistants and the Illinois Academy of Physician Assistants.
Research Team
Charlotte Gyllenhaal, Ph.D., is an ethnobotanist with a scientific focus and experience in integrative cancer therapy, traditional herbal medications, and discovering new drugs from plants. She earned an M.S. from Ohio State University and a Ph.D. from the University of Alabama. She is Research Program Director at the Block Center and a Research Assistant Professor at the University of Illinois at Chicago’s College of Pharmacy, Department of Medicinal Chemistry and Pharmacognosy. In addition to her position as Associate Editor of the peer-reviewed journal Integrative Cancer Therapies (Sage Science Publications), she has also worked on the editorial or consultant board of The Journal of Natural Products, Economic Botany and International Traditional Medicine Newsletter.
Amanda Koch, Ph.D., received her doctorate of pharmacognosy with a specialization in medical ethnobotany from the University of Illinois at Chicago in 2005. She was awarded an American Foundation for Pharmaceutical Education pre-doctoral fellowship, as well as the Al R.Langerman scholarship, the Charles P. Bondy award, a University of Illinois at Chicago Provost Award to help fund her field research. Named a Van Doren Scholar, she currently works as a research associate in the Block Center, and holds a post-doctoral position at the University of Illinois at Chicago.
