1. Division of Endocrinology, Diabetes, & Metabolism, Department of Medicine, Keck School of Medicine, University of Southern California , Los Angeles, CA 90033 , USA
2. Department of Endocrinology, Kaiser Permanente , Panorama City, CA 91402 , USA
3. Division of Endocrinology, Lundquist Institute , Torrance, CA 90509 , USA
4. Division of Endocrinology, Diabetes and Metabolism, Harbor-UCLA Medical Center , Torrance, CA 90509 , USA
5. Endocrine Section, Medstar Washington Hospital Center , Washington, DC 20010 , USA