1. Gastroenterology and Endoscopy Unit, University Hospital of Parma, University of Parma, 43126 Parma, Italy
2. Department of Medicine and Surgery, University of Parma, 43125 Parma, Italy
3. Department of Biochemical Sciences, Pomeranian Medical University, 70204 Szczecin, Poland
4. University Division of Gastroenterology, City of Health and Science University Hospital, University of Turin, 10126 Turin, Italy
5. Department of Clinical Research, University of Southern Denmark, 5230 Odense, Denmark
6. Department of Gastroenterology, OUH Svendborg Sygehus, 5700 Svendborg, Denmark
7. Surgical Research Unit, Odense University Hospital, 5000 Odense, Denmark
8. Department of Social Medicine and Public Health, Pomeranian Medical University, 70204 Szczecin, Poland