1. Department of Internal Medicine; University of Texas Southwestern Medical Center; Dallas TX USA
2. The Charles and Jane Pak Center for Mineral Metabolism and Clinical Research; University of Texas Southwestern Medical Center; Dallas TX USA
3. Department of Clinical Sciences; University of Texas Southwestern Medical Center; Dallas TX USA
4. Department of Orthopaedic Surgery; University of Texas Southwestern Medical Center; Dallas TX USA
5. Department of Physiology; University of Texas Southwestern Medical Center; Dallas TX USA