1. Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas
2. Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas
3. Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas
4. Division of Nephrology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
5. Division of Mineral Metabolism, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas