1. Division of Gastroenterology; Ospedale di Acireale; Azienda Sanitaria Provinciale di Catania; Catania Italy
2. Department of Biomedical and Biotechnological Sciences; University of Catania; Catania Italy
3. The Liver Unit; Gastroenterology Department; Tel-Aviv Medical Center; Tel Aviv Israel
4. School of Public Health; University of Haifa; Haifa Israel