1. Gastroklinik, Private Gastroenterological Practice, 8810 Horgen, Switzerland
2. Gastroenterology Section, Hirslanden Klinik im Park, 8027 Zurich, Switzerland
3. Division of Gastroenterology and Hepatology, Medical University Department, Kantonsspital Aarau, 5001 Aarau, Switzerland
4. Department of Internal Medicine, Second Medical Clinic, Ippokration Hospital, Aristotle University of Thessaloniki, 54642 Thessaloniki, Greece
5. First Laboratory of Pharmacology, School of Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
6. Pancreaticobiliary Medicine Unit, University College London Hospitals (UCLH), London W1W 6DN, UK