1. Department of Gastroenterology and Hepatology; Section of Nutritional Medicine; Charité - Universitätsmedizin Berlin; Berlin Germany
2. Department of Microbiology and Hygiene; Charité - Universitätsmedizin Berlin; Berlin Germany
3. Center for Clinical Studies; University Hospital Regensburg; Regensburg Germany
4. Medical University Innsbruck; Rectorate Innsbruck Austria