1. 1st Department of Internal Medicine, Faculty of Medicine, Semmelweis University, Budapest, Hungary;
2. Department of Surgery, Faculty of Medicine, University of Debrecen, Debrecen, Hungary;
3. Medical Services, Ralph H. Johnson VA Medical Center, Charleston, SC, USA;
4. Hemodialysis Unit, Fresenius Medical Care Hungary, Hatvan, Hungary;
5. Department of Pathophysiology, International Nephrology Research and Training Center, Semmelweis University, Budapest, Hungary