1. Department of Medicine, Surgery and Pharmacy, University of Sassari, 07100 Sassari, Italy
2. Department of Biomedical and Clinical Sciences Luigi Sacco, Luigi Sacco Hospital, University of Milan, 20157 Milan, Italy
3. Cardiology Unit, Azienda Ospedaliero, Universitaria di Sassari, 07100 Sassari, Italy
4. Department of Biochemical Science, University of Sassari, 07100 Sassari, Italy