1. Department of Gastroenterology, Hepatology and Endocrinology Medical University Hannover Hannover Germany
2. Department of Neuroscience Uppsala University Uppsala Sweden
3. Research Unit of Biomedicine & Biocenter of Oulu, Medical Research Center (MRC) University of Oulu, University Hospital Oulu Finland
4. Department of Gastroenterology and Metabolism Poznan University of Medical Sciences Poznan Poland