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Donald Muir, MD

President GMP Network

Dr. Muir graduated from the University of Michigan Medical School in 1985. He works in Clinton Township, MI and specializes in Family Medicine and is certified by the American Board of Family Medicine, Dr. Muir is affiliated with Henry Ford Macomb Hospital.

Ronald Barnett, DO, FACOI

Vice President GMP Network, Treasurer

Dr. Barnett graduated from Michigan State University, College of Osteopathic Medicine in 1986. Dr. Barnett specializes in Internal Medicine and Geriatrics. He is board certified in Internal Medicine with a sub-specialty in Geriatric Medicine. He provides comprehensive care to patients in all clinical settings including office, hospital, home and long-term care facilities. Dr. Barnett’s practice in St. Clair Shores and he is affiliated with Henry Ford Macomb Hospital and St. John Macomb Oakland and McLaren Macomb Medical Center.

Carolann Kinner, DO

Secretary GMP Network

Dr. Kinner attended medical school at Michigan State University in East Lansing, Michigan. She is board certified by the American Osteopathic Board of Internal Medicine. Dr. Kinner has an emphasis on comprehensive and preventative care as part of Diab and Kinner Internal Medicine, PC., in Warren, MI.

Omokayode Osobamiro, MD

Dr. Omokayode Osobamiro, MD is a nephrology specialist in Clinton Township, MI and has been practicing for 35 years. He graduated from University of Ibadan / College of Medicine in 1983 and specializes in nephrology and critical care medicine.

Dr. Osobamiro is Board Certified by the American Board of Internal Medicine - Critical Care Medicine, American Board of Internal Medicine – Nephrology, American Board of Internal Medicine - Internal Medicine. Henry Ford Macomb Hospital, Internal Medicine, MI, 1995. Dr. Osobamiro completed his residency at Henry Ford Detroit, Internal Med. In 1995.

Jixian Wu, MD

Jixian Wu, MD is a practicing Internist in Troy, MI. Dr. Wu graduated from Shanghai School of Medicine in 1990 and has been in practice for 28 years. He completed a residency at St John Hospital. Dr. Wu also specializes in Hospitalist. He currently practices at IPC The Hospitalist Company and is affiliated with DMC Harper University Hospital, DMC Sinai-Grace Hospital and Henry Ford Macomb Hospital Clinton Township. Dr. Wu is board certified in Internal Medicine.

Rajika Lasitha Munasinghe, MD, MS, MBA, FACP

President, Academic Internal Medicine Specialists, Site Director

Dr. Rajika Munasinghe is board certified in internal medicine, with a masters degree is biostatistics and epidemiology from the Medical College of Wisconsin and a MBA from the Broad College of Business at Michigan State University. Dr. Munasinghe completed his residency at Wayne State University, and now serves as a clinical associate professor at the school. He has been associate program director of the Internal Medicine Residency Program at Sinai-Grace since 2000. At AIMS, Dr. Munasinghe oversees the financial operations, information systems and strategic planning of the organization as well as providing inpatient hospital care. He recently earned his master's in business administration (MBA) from Michigan State University's Executive MBA Program.

James C. Martin, D.O

Medical Director

Graduated from Des Moines University Osteopathic Medical School in 2002. Joined GMPN in 2012 as Medical Director in charge of the Blue Care Network contract. Dr. James Martin is board certified in Family Medicine and practices in Shelby Township. He has experience being an employed physician for ten years as part of the Henry Ford Health System and as a private practice physician since 2016.

Thomas J. Neuner, DC, JD

Dr. Neuner is past administrator of Michigan Spine and Joint Center, an integrated group of spine care specialists collectively providing services which include chiropractic, physiatry, interventional pain management and physical therapy. Dr. Neuner was also an allied chiropractic physician with Michigan Head and Spine Institute, one of our nation’s largest neurosurgical groups. Currently retired from direct patient care spanning 1984 to 2020 , Dr. Neuner now maximizes his keen interest and expertise in the integration, collaboration and coordination of varied health care practitioners within the field of spine care continuum through Spine Care Partners, LLC. consulting group. Implementation and support of value-based care delivery and reimbursement strategies within this space is of prime focus. Dr. Neuner is a 1984 graduate of National University of Health Sciences. Dr. Neuner is also a medical attorney of 22 years holding a J.D. degree from Detroit College of Law, Michigan State University, admitted to the Michigan Bar in 1996. He is a member of the Michigan Health Lawyers Association and American Bar Association.

Marcus Koss, MD

Dr. Koss is a family medicine physician who graduated from Wayne State University School of Medicine in 1999. He is board certified by the American Board of Family Medicine. After being an employed physician in Roseville, MI for 9 years, Dr. Koss opened a private practice in 2022 in Saint Clair Shores, MI. He focuses on outpatient care and is affiliated with Henry Ford Macomb and Beaumont Grosse Pointe hospitals.

Angela Vanker

Executive Director, GMP Network

Angela Vanker has over 15 years of experience working with and advocating for physician practices. She served as the Director of Practice Transformation at Alliance Health, where she designed and implemented integrated care teams in primary care, including care management and behavioral health. She also served as a Director of Quality Initiatives at MPRO, a quality improvement service provider for the State of Michigan.