1. First Department of Surgery, Laikon General Hospital, National and Kapodistrian University of Athens, Athens, Greece
2. School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
3. Department of Gastroenterology, Hygeia Hospital, Athens, Greece
4. Department of Immunology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
5. Second Department of Propaedeutic Surgery, National and Kapodistrian University of Athens, Athens, Greece
6. Hepatogastroenterology Unit, Second Department of Internal Medicine and Research Unit, “Attikon” University General Hospital and National and Kapodistrian University of Athens, Haidari, Greece