One of the US private practitioners who made inestimable research contributions was Vince Barranco (1937-2013) from Tulsa, Oklahoma. Vince was born in Granada, Mississippi, and trained in dermatology under Mark Allen Everett at the University of Oklahoma. In 1969 he joined Dwane Minor and Kendrick Doran at the Tulsa Dermatology Clinic.
Vince became fascinated by dapsone during his residency and decided to investigate its method of action. The clinic was in a new building that was designed with foresight to accommodate 4 physicians with 4 suites of examining rooms radiating out from a central nursing area. One wing was free; it became Vince’s laboratory. He acquired 28 rabbits and injected them with large doses of vitamin A daily, inducing upregulation of lysosomal enzymes, damage to chondroitin sulfate, and floppy ears. Vince set up a classic study: 8 rabbits received vitamin A alone; 8, vitamin A plus methylprednisolone; and 8, vitamin A plus dapsone; and 4 served as controls. The distal ear tips collapsed in the rabbits treated with vitamin A alone by day 5; systemic signs of toxic effects and hair loss appeared by day 8. Both dapsone and methylprednisolone blocked the ear changes and reduced hair loss, although systemic toxic effects were not influenced.