Dr. Barrios received his first academic appointment at the Universidad Nacional Autonoma de Mexico as Assistant Professor of Histology and Pathology in the Department of Chemistry in 1978. In 1982, he was promoted to full Professor in the Department of Cell Biology, and elected Head of the Department of Electron Microscopy at the same institution. He then became Chairman of the Department of Pathology at the Mexican Cardiology Institute and later Chairman of Pathology at the National Institute for Respiratory Diseases in Mexico City. He was visiting professor from 1990 through 1992 in Dr. Michael Lieberman’s laboratory at Baylor College of Medicine, conducting molecular biology studies. In 1992, Dr. Barrios was appointed Associate Professor in the Department of Pathology at Baylor College of Medicine, where he led numerous conferences and lectures for medical students. In 2004, he assumed his positions at Houston Methodist Hospital as Professor of Pathology and Laboratory Medicine at Weill Cornell Medical College.

Dr. Barrios has worked with experimental pathology projects for the last twenty-eight years, while at the same time his primary area of interest in diagnostic pathology has been pulmonary and renal pathology. His current projects include the study of interstitial lung diseases and pulmonary neoplasms. His collaborations in experimental pathology are related to oncogenesis and oxygen toxicity.