1. Department of Molecular Biology, Universidad Panamericana, School of Medicine, Campus México, Mexico City
2. Department of Gastroenterology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
3. PECEM, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
4. Department of Medicine, Universidad Veracruzana, Veracruz, Mexico
5. Department of Gastroenterology and Hepatology, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, Sichuan Province, China
6. Department of Surgery, University of Colorado Anschutz Medical Campus, Denver, Colorado