(May 14, 2018, 10:47 AM EDT) -- PITTSBURGH — A former radiologist at the University of Pittsburgh Medical Center (UPMC) on May 3 pleaded guilty to charges of health care fraud and unlawfully prescribing Vicodin, according to documents filed in Pennsylvania federal court (United States v. Marios Papachristou, No. 18-cr-0084, W.D. Pa.)....