1. Department of Medicine Second Medical Clinic, Aristotle University of Thessaloniki, Ippokration Hospital Thessaloniki Macedonia Greece
2. Pancreaticobiliary Medicine Unit University College London Hospitals (UCLH) London UK
3. First Laboratory of Pharmacology School of Medicine, Aristotle University of Thessaloniki Thessaloniki Macedonia Greece
4. Midwifery Department School of Healthcare Sciences, University of West Macedonia Kozani Macedonia Greece
5. Gastroenterology Department Theageneio Hospital Thessaloniki Macedonia Greece
6. Department of Gastroenterology General Military Hospital of Athens Attiki Greece
7. Gastroklinik, Private Gastroenterological Practice Horgen Switzerland
8. Department of Gastroenterology and Hepatology University of Zurich Zurich Switzerland