Our Physicians

Renee R. Lefland, M.D.

Dr. Renee Lefland has been practicing Internal Medicine for over 25 years. She graduated from Cornell University with a B.S. in Microbiology in 1984. She attended the University of Vermont College of Medicine where she obtained her M.D. in 1988. She completed her medical residency at Winthrop University Hospital and started her own practice in 1991. She is a board certified physician and is a Clinical Assistant Professor of Medicine at Stony Brook University School of Medicine. Dr. Lefland is an attending physician at Winthrop University Hospital, North Shore University Hospital in Manhasset and Mount Sinai Hospital in Manhattan. She has been named TOP INTERNAL MEDICINE DOCTOR by Castle Connolly and Newsday. Dr. Lefland was recently awarded a certificate of recognition for her work in teaching medical students and medical residents at Winthrop Hospital and Stony Brook University School of Medicine. Dr. Lefland is married and has 3 daughters.

Monisha Sen, M.D.

Monisha Sen MD graduated cum laude from Princeton University. She then attended Mount Sinai School of Medicine in NYC. She completed her internship and residency in Internal Medicine at Long Island Jewish Medical Center. She has been working with Dr. Lefland for over 15 years in their busy Internal Medicine practice. Dr. Sen has an interest in travel medicine and preventive health care. Dr. Sen is married and has two children.

Pamela Stimler, M.D.

Pamela Stimler MD is a board certified internist with a strong interest in women’s health and preventive medicine. Her education includes a B.S. degree from The Sophie Davis School for Biomedical Education at City College of New York – Magna Cum Laude, and M.D. from Stonybrook Medical School. Dr. Stimler completed her internal medicine residency, including an appointment as chief medical resident, at Nassau County Medical Center in East Meadow. She is affiliated with Northwell – Long Island Jewish Medical Center, Maimonides Medical Center and NY Methodist Hospital.

Dr. Stimler is married, lives in Queens and has two children.

Xia Chen, M.D.

Dr. Xia Chen graduated cum laude from Columbia University where she obtained a B.S. in biomedical engineering. She then attended Stony Brook University where she obtained her M.D. She completed her internship and residency in internal medicine at Albert Einstein-Montefiore. Prior to joining the practice, Dr. Chen worked at Elmhurst Hospital, an affiliate of Mount Sinai Hospital, where she taught residents of the program. Dr. Chen is board certified in internal medicine.

Dr. Chen is married and has 2 children.

Greg S. Kaufman, M.D.

Dr. Greg Kaufman has been a member of the practice since 2006. He is a native New Yorker and currently lives in Queens with his wife and 3 children.

Dr. Kaufman received his M.D. from Hahnemann University/Drexel University School of Medicine in Philadelphia, where he was elected into medicine’s honor society (Alpha Omega Alpha). He completed his internship and residency in Internal Medicine at Mount Sinai Medical Center N.Y, N.Y and completed fellowship training in Cardiovascular Disease at Beth Israel Medical Center N.Y, N.Y.

Dr. Kaufman is board certified in Cardiovascular Disease, Nuclear Cardiology, and Adult Echocardiography.

Dr. Kaufman runs an office-based consultative practice which offers a full suite of diagnostic cardiovascular imaging and he has a particular interest in developing and fostering a patient centered approach to the primary prevention and treatment of cardiovascular disease.

Dr. Kaufman is affiliated with Winthrop University Medical Center and he has close working relationships with leading sub-specialists at North Shore University Medical Center, St. Francis Medical Center, and Mount Sinai Medical Center.

Michael C. Barth, M.D. F.A.C.G.

Dr. Michael C. Barth was trained in Internal Medicine with a Gastroenterology Fellowship at Beth Israel Medical Center in New York City; he is a former teaching staff member at the Albert Einstein College of Medicine in the Bronx, New York. He is a Fellow of the American College of Gastroenterology (ACG) and a member of the American Society for Gastrointestinal Endoscopy (ASGE), American Gastroenterological Association (AGA) and the American College of Physicians.

As a Gastroenterologist, Dr. Barth specializes in digestive disease and disorders, endoscopy, colonoscopy, capsule endoscopy, and Bravo PH studies. Dr. Barth has extensive experience in the field of Gastroenterology, is highly skilled, and works continuously to update his medical knowledge. He has been in private practice since 1995. He and his staff strive to offer the highest quality of health care possible. Dr. Barth is affiliated with Winthrop University Hospital in Mineola, Mercy Medical Center in Rockville Centre, South Nassau Communities Hospital in Oceanside, and he is the Medical Director of Meadowbrook Endoscopy Center in Westbury.

Dr. Barth’s commitment to health care extends beyond his own practice. His concern for the uninsured and underserved in the community led him to work with other physicians at Meadowbrook Endoscopy Center to provide free colorectal cancer screening and education to the uninsured individuals in the surrounding community.

Jordan Rush, M.D.

Dr. Jordan Rush is a Board Certified Gastroenterologist specializing in digestive diseases. He graduated from Emory University before he went on to the University at Buffalo School of Medicine where he graduated with honors and was elected into the medical honor society, Alpha Omega Alpha. He then completed Internal Medicine training at The Mount Sinai Medical Center in Manhattan followed by fellowship training in Gastroenterology and Hepatology at Winthrop University Hospital. Dr. Rush had additional training in liver disease and transplant hepatology at Columbia Presbyterian and completed an Inflammatory Bowel Disease Fellowship, through the Crohn’s and Colitis Foundation, at The Mount Sinai Medical Center.

Dr. Rush is a member of the American College of Gastroenterology and American Gastroenterological Association. He is affiliated with Winthrop University Hospital in Mineola, South Nassau Communities Hospital in Oceanside, and Mercy Medical Center in Rockville Centre. Dr. Rush was born and raised on Long Island, he is married with 2 children.