1. Gastroenterogy Unit; Versilia Hospital; Azienda USL Toscana Nord Ovest; Lido di Camaiore Italy
2. Clinical Pharmacology and Digestive Pathophysiology Unit; Department of Clinical and Experimental Medicine; University of Parma; Parma Italy
3. Department of Medical and Surgical Sciences; S. Orsola Hospital; University of Bologna; Bologna Italy
4. JB Medical Ltd; Sudbury UK
5. Gastroenterology Unit; ‘Spedali Civili’ Hospital; University of Brescia; Brescia Italy