1. Department of Internal Medicine/Endocrinology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8857, USA
2. Department of Internal Medicine and Diabetology, Poznan University of Medical Sciences, Poznan, Poland
3. Department of Internal Medicine/Endocrinology, Department of Population and Data Sciences, University of Texas Southwestern Medical Center, Dallas, TX, USA