1. Clinic of Nephrology and Renal Transplantation, Laiko General Hospital, Medical School of Athens, National and Kapodistrian University of Athens, Athens, Greece
2. Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
3. Cardiovascular Prevention & Research Unit, Clinic & Laboratory of Pathophysiology, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece