**6. Acknowledgment**

These works were financially sponsored by the National Natural Science Foundation of China (No. 50973070, 51073105 and 30900691), and State Education Ministry of China (Doctoral Program for High Education, No. JS 20100181110031). We should also thank our laboratory members for their generous help, and gratefully acknowledge the help of Ms. H. Wang, of the Analytical and Testing Center at Sichuan University, for the SEM, and Ms Liang, of the Department of Nephrology at West China Hospital, for the human fresh blood collection.
