Objective To study the effect of exsomes in SH-SY5Y cells after hypoxic ischemia/reperfusion injury.Methods Human umbilical vein endothelial cell hypoxic ischemia/reperfusion (HUVEC I/R) injury models were established,and the exosomes derived from HUVEC I/R were extracted and identified.SH-SY5Y cell hypoxic ischemia/reperfusion injury models (SH-SY5Y I/R) were established,and cells from SH-SY5Y I/R were divided into control group and exosomes-treatedgroup.The proliferation of SH-SY5Y cells was evaluated by CCK-8 assay 24,48and 72 h after cell inoculation.Transwell assay and wound-healing assay were used to examine the invasion and migration.Hochest33258 staining and Flow cytometry were used to monitor the changes of cell cycle and apoptosis.Expressions of Caspase-3,Bax and Bcl-2 were measured by real-time fluorescence quantificative-PCR and Western blotting.Results As compared with those in the control group,the proliferation abilities of SH-SY5Y cells in exosomes-treated group were significantly promoted (48 h:0.70±0.05 vs.0.94±0.08;72 h:0.83±0.05 vs.1.02±0.06),the cell cycle rate of S phase was significantly increased (14.39％±4.11％ vs.20.54％±3.46％),and G0/G1 phase was statistically decreased (71.26％± 5.24％ vs.66.87％±4.23％,P＜0.05).What's more,cell invasive was significantly promoted (44.00±6.56 vs.70.67±6.11),and relative wound injury area was significantly reduced in the exosomes treated group (0.61±0.07 vs.0.52±0.10);significant differences were noted between the two groups (P＜0.05).The mRNA expressions of Bax and Caspase-3 were significantly decreased and the mRNA expressions of Bcl-2 was significantly increased in the exosomes-treated group as compared with those in the control group (P＜0.05).Conclusion HUVEC I/R-derived exosomes play neuro-protective role in human SH-SY5Y cells after hypoxic I/R injury.

Rapid palatal expansion (RPE) is commonly used to correct transverse maxillary deficiencies and recognized as a reliable orthopedic procedure in children and adolescents. For adults, however, conventional RPE has been considered rarely successful and can produce undesirable dental effects. Along with the development of digital techniques and mini-implant anchorage, a novel method called miniscrew-assisted RPE (MARPE) has become available for the treatment of maxillary transverse deficiency in older patients recently. In this article, the biomechanical principles and indications of MARPE, the advances in device design, the clinical effects, the matters needing attention and limitations of this method, and the stability after expansion are discussed.