1. Harold Simmons Center for Kidney Disease Research and Epidemiology, School of Medicine, University of California Irvine, Orange, CA, USA
2. Division of Nephrology, Department of Internal Medicine, Ewha Medical Research Center, Ewha Womans University College of Medicine, Seoul, South Korea
3. Division of Nephrology, Department of Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, South Korea
4. Nephrology Division, Department of Internal Medicine, NHIS Ilsan Hospital, Goyang, South Korea
5. Nephrology Section, Memphis Veterans Affairs Medical Center, Memphis, TN, USA
6. Division of Nephrology, University of Tennessee Health Science Center, Memphis, TN, USA
7. Nephrology Section, Tibor Rubin VA Medical Center, Long Beach, CA, USA