Author contributions
The authors’ responsibilities were as follows—XP, SC, LuZ, YL, CW and ST contributed to the conception and design of this study. XP, SC, LuZ, YL, CW, LiZ, WC, JZ and JY were involved in the acquisition and analysis of the data. XP, LiZ and LuZ interpreted the results. XP, SC and ST drafted the manuscript. All authors read and approved the final manuscript.