1. VA Greater Los Angeles Healthcare System and Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, UCLA David Geffen School of Medicine, 900 Veteran Avenue, 24-130 Warren Hall, Los Angeles, CA 90095, USA
2. Department of Medicine, Veterans Affairs Greater Los Angeles Healthcare System and Division of Endocrinology, Departments of Medicine and Physiology, UCLA David Geffen School of Medicine, 11301 Wilshire Boulevard, Los Angeles, CA 90073, USA