1. Department of Internal Medicine III, Ludwig Maximilians University Munich, Munich, Germany
2. Department of Internal Medicine II, Klinikum rechts der Isar II, Technische Universität München, Munich, Germany
3. Divison of Digestive and Liver Disease, Columbia University Medical Center, New York, NY, USA
4. Herberg Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY, USA