John L. Zenk

American Medical Association engages in promoting the art and science of medicine and the betterment of public health. It offers services to physicians, residents, medical students, and patients. The company was founded by Nathan Smith Davis in 1847 and is headquartered in Chicago, IL.

The American Academy of Anti-Aging Medicine, Inc. operates as a nonprofit organization that promotes the field of anti-aging medicine and trains and certifies physicians in this specialty. It engages in the advancement of technology to detect, prevent, and treat aging related disease and to promote research into methods to retard and optimize the human aging process. The company was founded by Ronald M. Klatz and Robert M. Goldman in 1992 and is headquartered in Boca Raton, FL.

American College of Physicians, Inc. operates as a medical-specialty organization. It is a national organization of internists and physician specialists who apply scientific knowledge and clinical expertise to the diagnosis, treatment, and care of adults from health to complex illness. Its members include internists, internal medicine subspecialists, medical students, residents, and fellows. The company was founded in 1915 and is headquartered Philadelphia, PA.

Humanetics Corp. engages in development and commercialization of bioactive compounds. Its products include radiation modulators, mechanism of action, safety and toxicology, and pharmacokinetics. It focuses on oncology, medical imaging, and medical countermeasures. The company was founded by Ronald J. Zenk in 1988 and is headquartered in Edina, MN.