Objective:To explore the influencing factors of postoperative graft stenosis in patients undergoing left internal mammary artery-left anterior descending branch (LIMA-LAD) coronary artery bypass graft (CABG) surgery.Methods:A retrospective analysis of the clinical data of 86 patients who were admitted to the Second Affiliated Hospital of Hainan Medical College and received coronary angiography after CABG surgery from July 2019 to December 2020 due to recurrent chest tightness, chest pain and other symptoms. According to the degree of stenosis of the LIMA-LAD graft, the patients were divided into stenosis group ( n=25) and non-stenosis group ( n=61). The graft stenosis of patients in the stenosis group was ≥50%, and the graft stenosis of patients in the non-stenotic group was less than 50%. The general information, past medical history, CABG intraoperative data, current visit data and biochemical indicators of the two groups were compared. Measurement data were expressed as mean±standard deviation ( Mean± SD), comparison between groups was by t-test; count data comparison between groups was by Chi-square test. Logistic regression analysis was used to screen out the influencing factors of graft stenosis after CABG. Use the rms package in the R 4.0.2 software to build a nomogram prediction model. Using receiver operating characteristic (ROC) curve to evaluate the discriminative degree of the model. Use the calibration curve and deviation correction C-index to evaluate the nomogram prediction model. Use X-tile software to obtain the cutoff value of the nomogram model integral, use Kaplan-Meier method to draw the survival curve, and use Log-rank to test. Results:Logistic regression analysis showed that smoking, hypertension, pre-CABG left anterior descending branch (LAD) stenosis <75%, pre-CABG left internal mammary artery (LIMA) blood flow, and coronary angiography diffuse lesions are independent risk factors that affect LIMA-LAD graft stenosis after CABG ( P<0.05). The C-index value predicted by the nomogram model was 0.879 (95% CI: 0.818-0.955, P<0.001). The area under the ROC curve was 0.712 (95% CI: 0.594-0.801, P<0.001), with good discrimination. The calibration curve shows that the accuracy of the model prediction was good. Through the X-tile software screening to obtain the model score cutoff value, the patients were divided into low-risk group (≤54 points), medium-risk group (>54 points and ≤112 points), and high-risk group (>112 points). The results of survival analysis showed that the incidence of postoperative graft stenosis in the three groups was 20.9%, 50.0% and 80.0%, respectively. Conclusions:Smoking, hypertension, LAD stenosis before CABG <75%, LIMA blood flow before CABG, and coronary angiography diffuse lessions are independent risk factors that affect LIMA-LAD graft stenosis after CABG. The construction of a nomogram prediction model can provide a reference for evaluating the patency of the LIMA-LAD graft vessel before CABG operation, and reduce the probability of LIMA-LAD graft vessel stenosis after CABG operation.

OBJECTIVE To investigate the role of gonadotropin-releasing hormone (GnRH) in es-tradiol(E2 ) induced advance of puberty onset in rats. METHODS Postnatal day 18 SD rats were given a daily intragastric administration of corn oil or E2(50 μg.kg-1 ) for consecutive 5 d. The day of vaginal opening (VO), pathological changes in ovary and protein expression levels of GnRH, G protein-coupled receptor 54 ( GPR54) and phospholipase C ( PLC) in hypothalamus were observed. RESULTS As compared to corn oil controll group, VO was advanced by about 12.2 d, corpus luteum was observed in the ovary section, and the protein expression levels of GnRH,GPR54 and PLC in hypothalamus were significantly increased by 47%, 55% and 56% in E2 group, respectively. CONCLUSION E2 induced onset of puberty advance may be closely related to regulation of the expression of GnRH, GPR54 and PLC in hypothalamus.

The injury of vascular endothelial cell function is the beginning of the pathological process of atherosclerosis. Mitochondrial oxidative stress is closely related to vascular endothelial cell function, which causes the dysfunction of vascular endothelial cell by inducing mitophagy, reducing nitric oxide production, inflammation, cellular metabolic imbalance and apoptosis. Meanwhile, vascular endothelial cell could also maintain their homeostasis by regulating mitochondrial oxidative stress. The molecular signaling pathways of the vascular endothelial cell injury caused by mitochondrial oxidative stress in the pathological process of atherosclerosis were outlined in this review, which provided reference for further research on the molecular mechanism between mitochondrial oxidative stress and endothelial damage.

Objective:This study was performed to assess the effect of glycemic control on atrial fibrillation recurrence rates after heart surgery concomitant with Cox-Maze Ⅳ ablation.Methods:A retrospective analysis was performed on 317 diabetic patients with atrial fibrillation who underwent cardiac surgery combined with Cox-Maze Ⅳ ablation in our hospital from May 2016 to February 2020. The patients were followed up for(37.7±27.7) months, and the data of atrial fibrillation recurrence and clinical outcome were collected and compared. The limited cubic spline model was used to analyze the dose-relationship between HbA1c level and the recurrence of atrial fibrillation. The univariate and multivariate Cox proportional regression analysis was used to explore the risk factors of recurrent atrial fibrillation after Cox-Maze Ⅳ ablation. Results:Higher glycated hemoglobin(HbA1c) at the time of ablation was associated with higher post-ablation recurrence rates. The cumulative survival freedom from atrial fibrillation recurrence for patients with HbA1c ≥7.4% at time of operation at 12, 24, 36 and 48 months were 96.3%、75.8%、52.7% and 35.7%, respectively( P<0.001). Besides, the rates of all-cause mortality, cardiac mortality and rehospitalization were significantly lower in patients with HbA1c<7.4%(1.7% vs. 6.3%, P=0.03; 1.1% vs. 5.6%, P=0.02 and 5.7% vs. 20.4%, P=0.01). The multivariate Cox regression model showed that HbA1c was an independent risk factor for atrial fibrillation recurrence( P<0.05). Conclusion:Higher preoperative HbA1c levels were associated with increased recurrence of atrial fibrillation and adverse clinical outcomes in patients undergoing cardiac surgery combined with Cox-Maze Ⅳ ablation.