Kazuhiro Shiizaki serves as an Instructor in the Department of Pathology in University of Texas Southwestern Medical Center at Dallas, TX, USA. He earned an M.D. degree from Jichi Medical University Shimotsuke, Japan, in 1995 and a Ph.D. degree from Wakayama Medical University Wakayama, Japan, in 2005. He has investigated the cell and molecular biology on parathyroid, bone, and vitamin D signaling for more than 10 years. The current interests are aging, bone and mineral metabolism, and chronic kidney disease.