1. Department of Cardiology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, People's Republic of China.
2. Department of Geriatrics, No. 411 Hospital of People's Liberation Army, Shanghai, People's Republic of China.
3. Department of Nephrology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, People's Republic of China.
4. Department of Research, Center for Stem Cell Biology, Roger Williams Medical Center, Boston University School of Medicine, Providence, Rhode Island.