1. Northwestern University—The Feinberg School of Medicine Chicago Illinois USA
2. Arbor Research Collaborative for Health Ann Arbor Michigan USA
3. National Institute of Diabetes and Digestive and Kidney Diseases Bethesda Maryland USA
4. Duke University Medical Center Durham North Carolina USA
5. Departments of Surgery and Anesthesiology, Division of Urologic Surgery Washington University School of Medicine St Louis Missouri USA
6. University of Washington Medical Center Seattle Washington USA
7. University of Michigan Ann Arbor Michigan USA