1. Department of Clinical and Experimental Medicine "F. Magrassi & A. Lanzara,", Second University of Naples, Naples. Italy.
2. Division of Medicine, Hospital of Ciriè, Turin, Italy.
3. Department of Clinical Pathology, Second University of Naples, Naples. Italy.
4. Section of Endocrinology, Diabetes, and Nutrition, Boston Medical Center, Boston University School of Medicine, Boston, Massachusetts.
5. Institute of Endocrinology, University of Milan, Milan, Italy.