Greensboro-based Proficient Health, an information technology company specializing in secure exchanges between health care entities, has merged with Raleigh company MD Interconnect Inc. The Triangle-rooted firm operates a mobile communication platform for health care providers. The two companies will operate as Proficient Health and have 31 employees after the merger. MDI co-founders Dr. David Hoover and Karen Hohenstein will join Proficient Health. Hoover, a pediatric surgeon at WakeMed, will...