1. Department of Medicine and Surgery, University of Parma , via Gramsci 14, 43126 Parma , Italy
2. Gastrointestinal Unit , Department of Medical and Surgical Sciences, , via Montericco 4, 40026 Imola (BO) , Italy
3. Hospital of Imola, University of Bologna , Department of Medical and Surgical Sciences, , via Montericco 4, 40026 Imola (BO) , Italy
4. Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa , via Savi 10, 56126 Pisa , Italy
5. Museum of Human Anatomy “Filippo Civinini”, University of Pisa , via Roma 55, 56126 Pisa , Italy