1. Division of Gastroenterology; Department of Internal Medicine; Santa Marta Santa Venera Hospital; Acireale (Catania)
2. Department of Drug Sciences; University of Catania; Catania Italy
3. Division of Gastro-Hepatology; Department of Internal Medicine; University of Torino; Torino
4. Department of “G.F. Ingrassia”; University of Catania; Catania Italy