1. Division of Endocrinology, Diabetes, and Metabolism (H.-S.M., S.-Y.K., O.-P.H., F.M., J.P., C.S.M.), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215;
2. Department of Clinical Biochemistry (M.D.), Attikon General University Hospital, Athens University Medical School, Athens 15784, Greece;
3. Division of Endocrinology and Metabolism (S.-Y.K.), School of Medicine, Chosun University, Gwang-Ju 501-717, South Korea;
4. Second Medical Clinic (S.A.P.), Aristotle University of Thessaloniki, Ippokration Hospital, Thessaloniki 11527, Greece;
5. Division of Endocrinology, Diabetes, and Hypertension (O.-P.H.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115;
6. Section of Endocrinology (C.S.M.), Boston VA Healthcare System, Harvard Medical School, Boston, Massachusetts 02118