Aim To investigate the effect of ranolazine postconditioning on myocardial apoptosis, the reperfusion injurysalvage kinase and the opening of MPTP in isolated rat hearts subjected to ischemia and reperfusion.Methods The langendorff mode was set up.Fifty-five SD rat hearts were randomly divided into 8 groups (n=7): ischema and reperfusion (I/R group),20 μmol·L~(-1) ranolazine postconditioning group(RPostC),ranolazine and the specific MPTP opener atractyloside group (RA), ranolazine and the specific ERK1/2 inhibitor PD98059 group (RP), ranolazine and the specific PI3K inhibitor PD98059 wortmannin group(RW), atractyloside group(A), PD98059 group (P) and wortmannin group (W). The isolated hearts were subjected to 30 minutes ischemia,10minutes drug postconditioning and 5 mitutes K-H buffer reperfusion.Myocardial apoptosis (TUNEL-positive cells), apoptotic index (AI), the opening of MPTP (spectrophotometry) and the The expression of p-AKT and p-ERK1/2 protein were measured at the end of reperfusion in each group.Results Compared with IR group, Myocardial AI and opening of MPTP were decreased in RPostC groups (P<0.05), the expression of p-AKT, p-ERK1/2 protein were increased in RPostC, RA, RP, and RW groups (P<0.05).There were no significant differences in other groups(P>0.05). Compared with RPostC group, Myocardial AI and opening of MPTP were increased in RA, RP, RW, A, P and W groups (P<0.05), and the expression of p-AKT、p-ERK1/2 protein were decreased in RP, RW, A, P and W groups (P<0.05). There were no significant differences of the expressions of p-AKT,p-ERK1/2 protein in RA groups (P>0.05). Compared with RA group, there were no significant differences in myocardial AI and opening of MPTP (P>0.05) and the expression of p-AKT and p-ERK1/2 protein were decreased in RP, RW, A, P and W groups (P<0.05).Conclusions Ranolazine postconditioning can attenuate myocardial apoptosis in isolated rat hearts subjected to ischemia and reperfusion via activation RISK pathway and inhibition of the opening of MPTP.

Background:Complete colonoscopy is key to the diagnosis and treatment of colorectal disease,its role in reducing the morbidity and mortality of colorectal cancer is well known.Nonetheless,there are numerous factors,not just from the endoscopist's perspective but also from the patient's,that can potentially increase the difficulty of completing a colonoscopy.Aims:To identify patient-related factors that influenced the difficulty of a colonoscopy.Methods:Through two rounds of expert consultation,the factors that might affect the difficulty of colonoscopy were selected.A total of 1621 consecutive painless colonoscopies from Jan.2021 to Jan.2022 at the endoscopy center of The Affiliated Wuxi People's Hospital of Nanjing Medical University were evaluated in a retrospective manner.Factors including demographic data,cecal insertion time,adenoma detection rate and so on were recorded.These factors were analyzed to determine their association with difficulty by using Logistic regression model.Results:A total of 29 patient-related factors affecting the difficulty of colonoscopy were selected.Through retrospective analysis,the mean age of 1621 cases was(47.45±13.27)years,of which 45.8%were male and the mean body mass index was(23.32±3.11)kg/m2.Logistic regression analysis revealed that age≥60 years(OR=2.890,95%CI:1.957-4.269,P<0.001),female gender(OR=0.324,95%CI:0.217-0.484,P<0.001),history of gynecological surgery(OR=14.895,95%CI:9.741-22.776,P<0.001),constipation for 20-30 years(OR= 1.412,95%CI:0.925-2.156,P=0.010)were independent risk factors for difficult colonoscopy.Conclusions:This retrospective study identified several patient-related factors that influence the technical difficulty of colonoscopy.These findings had implications for practice and teaching of colonoscopy.

Objective To evaluate the effect of water exchange method versus conventional methods including air insufflation and carbon dioxide insufflation method for the quality of colonoscopy.Methods We searched related randomized controlled trials published up to October 2022 from PubMed,Web of Science,the Cochrane Library,SinoMed databases,CNKI,Wanfang data.Two reviewers independently searched the literatures based on standards to extract the data and evaluate the quality.Meta-analysis was conducted by RevMan 5.4.1.Results 23 studies involving 10654 patients were included.Although cecal intubation time was prolonged in water exchange(MD=1.81,95％CI:1.28～2.35,P=0.000),but water exchange had higher adenoma detection rate(ADR)(O(R)=1.40,95％CI:1.26～1.55,P=0.000),cecal intubation rate(O(R)=1.62,95％CI:1.24～2.10,P=0.000)and scores of bowel preparation quality(MD=0.61,95％CI:0.42～0.79,P=0.000)compared with conventional colonoscopy.In addition,WE had significantly lower pain sores(MD=-1.07,95％CI:-1.39～-0.76,P=0.000),number of abdominal compression(O(R)=0.42,95％CI:0.29～0.60,P=0.000)and number of position change(O(R)=0.59,95％CI:0.42～0.82,P=0.002)than conventional colonoscopy.Conclusion Although water exchange colonoscopy prolongs cecal intubation time,but it can significantly increase ADR,cecal intubation rate and scores of bowel preparation quality.Beyond that,water exchange reduces patient pain,the proportion of abdominal compression and position change.Water exchange is a better choice for high-quality colonoscopy.