1. Biomedical Department of Internal Medicine and Medical Specialties, University of Palermo, Palermo, Italy
2. Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
3. Section of Clinical Biochemistry, University of Verona, Verona, Italy
4. CGH Medical Center, Sterling, Illinois; Ciccarone Center for the Prevention of Cardiovascular Disease, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
5. Department of Hypertension, Chair of Nephrology and Hypertension, Medical University of Lodz, Lodz, Poland