1. Magna Graecia University, Nephrology and Dialysis Unit , Catanzaro , Italy
2. Magna Graecia University, Department of Health Sciences , Catanzaro , Italy
3. Department of Nephrology, School of Medicine, University of Ioannina , Ioannina , Greece
4. Hemodialysis Unit, General Hospital of Filiates , Filiates , Greece
5. Second Department of Cardiology, University Hospital of Ioannina , Ioannina , Greece
6. Magna Graecia University, Experimental and Clinical Medicine , Catanzaro , Italy