1. Department of Nephrology and Endocrinology/Diabetology, Klinikum Ernst von Bergmann, Potsdam, Germany
2. Institute of Physiology, University of Zurich, Zurich, Switzerland
3. Helios-Klinikum, Berlin-Buch, Germany
4. Division of Nephrology, University Hospital Zurich, Zurich, Switzerland
5. Institute of Pathology, Charite Berlin, Germany