1. Division of Gastroenterology (E.B., E.V., E.G., M.R.) and Department of Internal Medicine (M.C.), Ospedale San Giovanni Battista, University of Turin, Turin, Italy;
2. Endocrine Unit (U.P., R.d.I., R.P.), Bologna, Italy;
3. Center for Applied Biomedical Research and Unit of Metabolic Diseases (R.M., S.N., G.M.), Department of Internal Medicine and Gastroenterology, University of Bologna, Bologna, Italy;
4. Metabolism Unit (A.G.), National Research Council Institute of Clinical Physiology and Department of Internal Medicine, University of Pisa, Pisa, Italy