1. Department of Medicine; St. Elizabeth Medical Center; Brighton MA USA
2. Liver Center; Department of Medicine; Beth Israel Deaconess Medical Center; Harvard Medical School; Boston MA USA
3. Department of Gastroenterology; University of Michigan; Ann Arbor MI USA
4. GI/Liver Unit; Institute of Digestive Diseases and Metabolism; University of Barcelona; Hospital Clinic and Institut d'Investigacions Biomèdiques August Pi-Sunyer (IDIBAPS); Barcelona Spain