Objective:To explore whether circular RNA HECTD1 (circ-HECTD1) is involved in oxygen-glucose deprivation (OGD)-induced neuronal cell damage by regulating the expressions of miR-98-5p/ephrin A4 (EPHA4).Methods:Mouse primary cortical neuronal cells were isolated and cultured in vitro. The targeting relations of circ-HECTD1 and miR-98-5p with EPHA4 were detected by dual luciferase reporter assay and RNA binding protein immunoprecipitation assay. These neurons were randomly divided into control group (cultured for 24 h under normal condition) and 6, 12 and 24 h OGD treatment groups (treated with OGD for 6, 12 and 24 h, respectively), OGD+Vector group and OGD+circ-HECTD1 group, OGD+small interfering RNA (siRNA) negative control (si-NC) group and OGD+siRNA circ-HECTD1 (si-circ-HECTD1) group, OGD+micro RNA (miR) negative control (miRNC) group and OGD+miR-98-5p mimic group, OGD+miRNA inhibitor negative control (anti-miRNC) group and OGD+miR-98-5p inhibitor (anti-miR-98-5p) group, OGD+miR-98-5p mimic+pcDNA group and OGD+miR-98-5p mimic+EPHA4 group, OGD+si-circ-HECTD1+anti-miR-NC group and OGD+si-circ-HECTD1+miR-98-5p inhibitor group; pCD5-ciR empty vector, pCD5-ciR-circ-HECTD1, si-NC, si-circ-HECTD1, miR-NC, miR-98-5p mimic, anti-miR-NC or anti-miR-98-5p were transfected into the neurons, and miR-98-5p mimi and pcDNA3.1 empty vector, miR-98-5p mimic and pcDNA3.1-EPHA4 overexpression vector, si-circ-HECTD1 and anti-miR-NC, or si-circ-HECTD1 and anti-miR-98-5p were co-transfected into the neurons. After 24 h of OGD treatment, the circ-HECTD1, miR-98-5p and EPHA4 mRNA expressions were detected by real-time fluorescent quantitative PCR (qRT-PCR), the EPHA4 protein expression was detected by Western blotting, the proliferation activity was detected by MTT assay, the apoptosis rate was detected by flow cytometry, the levels of interleukin (IL)-1β and tumor necrosis factor (TNF)-α in cell culture medium were detected by ELISA, and the activities of superoxide dismutase (SOD) and malondialdehyde (MDA) were detected by kit assay. Results:(1) Targeting relations between circ-HECTD1 and miR-98-5p, and EPHA4 and miR-98-5p were verified. (2) As compared with the control group, the neurons in 6, 12 and 24 h OGD treatment groups had significantly increased circ-HECTD1 and EPHA4 protein expressions and significantly decreased miR-98-5p expression ( P<0.05). (3) As compared with OGD+Vector group, OGD+circ-HECTD1 group had significantly increased circ-HECTD1 expression, and significantly decreased miR-98-5p expression ( P<0.05); as compared with OGD+si-NC group, OGD+si-circ-HECTD1 group had significantly increased miR-98-5p expression, and significantly decreased EPHA4 mRNA and protein expressions ( P<0.05); as compared with OGD+miR-NC group, OGD+miR-98-5p mimic group had significantly increased miR-98-5p expression, and significantly decreased EPHA4 protein expression ( P<0.05); as compared with OGD+anti-miR-NC group, OGD+anti-miR-98-5p group had significantly decreased miR-98-5p expression, and significantly increased EPHA4 protein expression ( P<0.05); as compared with the OGD+si-circ-HECTD1+anti-miR-NC group, OGD+si-circ-HECTD1+anti-miR-98-5p group had significantly increased EPHA4 mRNA and protein expressions ( P<0.05). (4) As compared with the control group, the OGD groups had significantly decreased cell viability and SOD activity, and significantly increased IL-1β and TNF-α levels, apoptosis rate and MDA activity ( P<0.05); as compared with the OGD+si-NC group, the OGD+si-circ-HECTD1 group had significantly decreased cell apoptosis rate, IL-1β and TNF-α levels, and MDA activity, and significantly increased cell viability and SOD activity ( P<0.05); as compared with the OGD+si-circ-HECTD1+anti-miR-NC group, the OGD+si-circ-HECTD1+anti-miR-98-5p group had significantly decreased cell viability and SOD activity, and significantly increased IL-1β and TNF-α levels, apoptosis rate and MDA activity ( P<0.05); as compared with the OGD+miR-NC group, OGD+miR-98-5p mimic group had significantly decreased cell apoptosis rate, IL-1β and TNF-α levels, and MDA activity, and significantly increased cell viability and SOD activity ( P<0.05); as compared with OGD+miR-98-5p mimic+pcDNA group, OGD+miR-98-5p mimic+EPHA4 group has significantly increased cell apoptosis rate, IL-1β and TNF-α levels, and MDA activity, and significantly increased cell viability and SOD activity ( P<0.05). Conclusion:Knockdown of circ-HECTD1 could ameliorate the OGD-induced neuronal cell damage in mice by targeting the expressions of miR-98-5p/EPHA4.

Objective:To investigate the pahtogengesis and pathology of delayed xenograft rejection (DXR) after pig to rhesus monkey heart xenotransplantation.Methods:Heterotopic xenogeneic heart transplantation in the abdominal cavity was performed using piglet as donors.4 monkeys were used as recipients.Complete complement depletion was achieve in the recipients treated with repetitive doses of a high activity cobra venom factor (Y CVF).The recipients were immunosuppressed with a combination of cyclosporine A,cyclophosphamide and steroids.Sera were analyzed for C3,C4 levels and complement activity and anti pig endotheliocyte xenoantibody.The graft were examined histopathologically and immunohistochemically for C3,C4,C5b 9,IgM,IgG,necrosis factor alpha (TNF alpha),intercellular adhesion molecule 1 (ICAM 1),CD57 (NK cells),CD68 (macrophages),CD4 and CD8.Results:The xenografts survived 8,10,13,13 days respectively and all grafts occoured DXR.Venular thrombosis was outstanding feature within DXR xenografts,complicated with interstitial edma,local hemorrhage and myocardial necrosis,with mild to moderate cellular infiltration.The serum C3 levels and complement activity almost decreased to 0 from the day of transplantation due to Y CVF,the C4 level began to decrease 2 4 days before the cardic xenografts losing their function.The anti pig endotheliocyte xenoantibody also decreased after transplantation,and slightly increased during DXR,all rejected xenografts showed C3,C4,C5b 9,IgG and IgM deposits in different degree.Large numbers of macrophages (50% of total leukocytes) were found infiltrating the entire xenograft,a few natural killer cells (8%～10%),some of CD4+T cells (15%) and CD8+T cells (25%) were detcted also,up regulation of ICAM 1 on the graft endothelial cells and TNF alpha in the interstitial were demonstrated in the rejected heart.Conclusion:Both Humor and cell mediated immunologic reaction may play an important role in pahtogengesis of DXR. [

Objective:To explore the relation among self-esteem, psychological flexibility and mental health in medical students, and to provide scientific reference for mental health education for medical students.Methods:A total of 788 medical students selected from a medical university in Chongqing City were investigated with the symptom checklist 90 (SCL-90), self-esteem scale (SES), acceptance and action questionnaire-Ⅱ (AAQ-Ⅱ), and cognitive fusion questionnaire-fusion (CFQ-F). SPSS 22.0 software was used for statistical analysis. T test, ANOVA, correlation analysis and tests for mediation effects were conducted. Results:There were significant differences in self-esteem and mental health level among medical students in gender and different grades ( t=-2.55, P<0.05; F=6.53, P<0.05). Mental health, self-esteem and psychological flexibility of medical students were correlated in pairs ( r=-0.528-0.694, P<0.01). Psychological flexibility played a partial mediation role between self-esteem and mental health of medical students, and the mediating effect accounted for 60.03% of the total effect. Conclusion:Self-esteem can directly predict the mental health of medical students, and can also indirectly affect mental health through psychological flexibility. Medical universities should carry out psychological education and promotion work with pertinence.