1. Fresenius Medical Care; Cegléd Hungary
2. Department of Internal Medicine; Semmelweis University; Budapest Hungary
3. Medical Services; Ralph H. Johnson VA Medical Center; Charleston South Carolina United States of America
4. Division of Nephrology, Department of Medicine; Medical University of South Carolina; Charleston South Carolina United States of America
5. Department of Internal Medicine; Louisiana State University Health Sciences Center; Shreveport Louisiana United States of America
6. Overton Brooks VA Medical Center; Shreveport Louisiana United States of America
7. Institute of Pathophysiology, Semmelweis University; Budapest Hungary
8. Fresenius Medical Care; Hatvan Hungary