Objective To investigate the role of p38 mitogen-activated protein kinase (p38MAPK) signaling pathway in reduction of myocardial ischemia-reperfusion (I/R) injury by morphine preconditioning in the rats with chronic heart failure in vitro.Methods Adult male Sprague-Dawley rats,weighing 200-230 g,aged 6-7 weeks,in which doxorubicin 2 mg/kg was injected via the tail vein once a week for 6 consecutive weeks to induce chronic heart failure,were studied.At the end of 8th week,30 rats with chronic heart failure were randomly divided into 5 groups (n =6 each) using a random number table:sham operation group (group Sham),I/R group,morphine preconditioning group (group MPC),SB203580 (p38MAPK inhibitor) + morphine preconditioning group (group SBM),and SB203580 group (group SB).The hearts were quickly excised and passively perfused in a Langendorff apparatus and subjected to 30 min of occlusion of the anterior descending branch of the left coronary artery followed by 120 min of reperfusion to establish the model of myocardial I/R injury.After equilibration,the hearts were subjected to 3 cycles of 5 min perfusion with K-H solution containing morphine 1 μmol/L at 5-min intervals before ischemia in group MPC.In group SBM,the hearts were perfused with K-H solution containing SB203580 (5 μmol/L) for 45 min starting from l0 min before morphine preconditioning until 5 min of ischemia.In group SB,morphine preconditioning was not performed,and the hearts were only perfused with K-H solution containing SB203580 (5 μmol/L) starting from 40 min before ischemia until 5 min of ischemia.At 15 min of equilibration (baseline),5 and 10 min of reperfusion,the coronary effluent was collected to detect the activity of lactate dehydrogenase (LDH) using the chemical colorimetry.At 10 min of reperfusion,the expression of phosphor-p38MAPK (p-p38MAPK) in the myocardium was determined by Western blot in Sham,I/R and MPC groups.At 120 min of reperfusion,the area at risk (AAR),total areas of right and left ventricles (LV+RV),and infarct size (IS) were measured,and the IS/AAR ratio was calculated.Results Compared with group Sham,the LDH activity in coronary effluent during reperfusion and IS/AAR ratio were significantly increased in the other groups,and the expression of p-p38MAPK was significantly up-regulated in I/R and MPC groups (P＜0.05).Compared with group I/R,the LDH activity in coronary effluent during reperfusion was significantly decreased,the expression of p-p38MAPK was significantly up-regulated,and the IS and IS/AAR ratio were significantly decreased in group MPC (P＜0.05),and no significant change was found in the LDH activity in coronary effluent,IS and IS/AAR ratio in SBM and SB groups (P＞0.05).Compared with group MPC,the LDH activity in coronary effluent during reperfusion was significantly increased,and the IS and IS/AAR ratio were significantly increased in group SBM (P＜0.05).Conclusion The mechanism by which morphine preconditioning reduces myocardial I/R injury is related to activation of p38MAPK signaling pathway in the rats with chronic heart failure in vitro.

Objective To investigate the association of single nucleotide polymorphism (SNP) in micro RNA-122 (miRNA-122) with genetic predisposition and early recurrence after resection for hepatocellular carcinoma(HCC).Methods This is a case-control study involving 173 HCC patients.DNA were exacted from cancer tissues embedded in paraffin and were amplified by PCR.The study aimed to explore SNP in gene sequence of miRNA-122 (357 base pair including extron.The outcomes of genetic predisposition were analyzed with early recurrence after resection for HCC.Results Only rs17669 was found in miRNA-122.The genetype frequence of C/C,T/T and C/T at rs17669 gene locus were 7(4.0％),110(63.6％)and 56(32.4％),respectively.When compared to T/T genetype,C/C genetype was a protective factor of risk of HCC (OR =0.213,95％ CI:0.062-0.732).Genetypes had no relationship with early recurrence after resection.Conclusion For HCC recurrence,rs17669 may be associated with genetic predisposition of HCC in Hans in Jiangxi infected with HBV.

Aim To screen the differentially expressed microRNAs ( miRNAs ) induced by hypoxia precondi-tioning ( HPC ) in adult rat cardiomyocytes, and pre-dict miRNAs-regulated target genes and their func-tions. Methods Cardiomyocytes were isolated from a-dult rat ventricular myocardium and cultured ( in vitro) . The cells were divided into 2 groups: control group ( CON ) and hypoxia preconditioning group ( HPC) . The cardiomyocytes in HPC group were sub-jected to 10 min hypoxia followed by 30 min reoxygen-ation, while the cells in CON group were cultured un-der normal condition. After that, total RNA was ex-tracted and then subjected to miRNA microarray to screen differentially expressed miRNAs. The microar-ray results were further validated by quantitative RT-PCR ( qRT-PCR ) . Bioinformatics analysis was per-formed to predict the miRNAs-regulated target genes and analyze the enriched gene ontology ( GO) and sig-naling pathway ( Pathway) . Results HPC caused sig-nificant changes in miRNAs expression in cardiomyo-cytes as compared to CON group. A total of 12 miR-NAs were up-regulated and 14 miRNAs were down-reg-ulated ( P <0. 01 , FDR <0 . 05 ) . The differentially expressed 7 miRNAs with a fluorescent signal intensity>500 were selected for further bioinformatics analysis. The expression of miR-133b-5p, miR-664-1-5p and miR-6216 detected by qRT-PCR exhibited the similar patterns of up or down regulation to those shown in mi-croarray results. Bioinformatics analysis revealed that miRNAs-regulated target genes were significantly en-riched in 27 GOs and 6 signal pathways. Conclusion
The expression profile of miRNAs in rat cardiomyo-cytes is significantly affected by HPC. These differenti-ally expressed miRNAs might participate in HPC-in-duced cardioprotection by regulating their target genes in rat cardiomyocytes.

Objective To investigate the effects of circumferential pulmonary vein isolation (CPVI) on atrial effective refractory period (ERP) in patients with paroxysmal atrial fibrillation.Methods 30 patients who underwent radiofrequency catheter ablation for paroxysmal AF were enrolled in this study.Using FAM mode,the RA and LA anatomical models were achieved in the CARTO 3 system.SVC,MRA,RAA,LA-A,LA-R,LA-P,LAA,LSPV,LIPV,RSPV,RIPV,CSp,CSd,were respectively located in the RA or LA anatomical model.Before and after CPVI,ERPs were measured in different locations of the atrium using programmed stimulation.The ERPs of the RA (SVC,MRA,RAA,CSp),LA (LA-A,LA-R,LA-P,LAA,CSd),PVs (LSPV,RSPV,LIPV,RIPV) were compared.Bilateral CPVIs were completed in all patients,and PV-LA bidirectional conduction block was achieved.The changes of electrophysiological characteristics of atrium before and after CPVI were observed.Results (1) ERP at different locations in the atrium before CPVI:Comparisons of ERPs at different locations of atrium:RAA had the minimal ERPs[(197.4 ± 28.6) ms (P ＜ 0.01);followed by PVs measuring,respectively,LSPV (213.0 ± 47.5) ms,LIPV (208.9 ± 45.9) ms,RSPV (209.3 ± 43.6) ms,RIPV (213.5 ± 48.1) ms and LAA (218.1 ± 27.7) ms.Comparisons of ERPs in RA,LA,and PVs showed:PVs had the lowest ERPs (211.2 ± 35.2) ms versus RA ERP (227.0 ± 23.7) ms versus LA ERP (241.0 ± 21.5) ms (P ＜ 0.05).(2) Comparisons of ERPs before and after CPVI:Comparisons of ERPs at different locations of atrium showed:RAA [(197.4 ± 28.6) ms vs.(208.6 ± 32.2) ms,P=0.003],CSp [(234.7 ± 29.1) ms vs.(246.9 ± 29.7) ms,P=0.007],LA-R [(242.9 ± 28.9) ms vs.(258.3 ± 26.9) ms,P=0.003],LA-P [(252.2 ± 28.5) ms vs.(261.1 ± 30.2) ms,P=0.039]and CSd [(238.6 ± 28.3) ms vs.(250.3 ± 23.6) ms,P =0.009].ERPs were found statistically prolonged at all different locations after CPVI.Comparisons of ERPs at RAand LA after CPVI showed:RA [(227.0 ± 23.7) ms vs.(235.9 ± 21.7)ms,P=0.002]and LA [(241.0 ± 21.5) ms vs.(249.7 ± 19.9) ms,P =0.001],which were statistically increased after CPVI.(3) A total of 90 episodes of atrial arrhythmias were induced before CPVI which were found at RAA (n =17),LAA (n =12),and PVs (n =36).After CPVI,8 episodes of atrial arrhythmias were induced which were found at,RAA (n =4),LAA (n =3),and SVC (n =1).Conclusions (1) Compared with other parts of atrium,ERPs at PVs,LAA and RAA are significantly shorter in patients with paroxysmal AF.At PVs,LAA and RAA,atrial arrhythmias are easily to be induce by programmed stimulation.(2) In patients with paroxysmal Af:PVs has the shortest ERPsfollowed by RAs whereas LA ERPs is the longest.There is a large ERP gradient change between PVs and LA.(3) The ERPs at RAs,LAs,As,and LA-PV are prolonged after CPVI.(4) Atrial arrhythmia is less likely to be induced after CPVI.

Objective To evaluate the effect of morphine preconditioning on the expression of miR-133b-Sp and Fas in rat cardiomyocytes subjected to hypoxia/reoxygenation (H/R).Methods Cardiomyocytes were isolated from healthy adult male Sprague-Dawley rats by using Langendorff perfusion.The cells were seeded into 24-well plates or 60 mm diameter dishes and randomly divided into 3 groups (n =24 each) using a random number table:control group (group C),group H/R,and morphine preconditioning group (group MPC).The cells in group C were cultured in normal culture atmosphere.In H/R and MPC groups,the cells were exposed to 95％ N2-5％ CO2 for 90 min followed by 120 min reoxygenation.In group MPC,the cells were cultured for 10 min in serum-free DMEM liquid culture medium containing morphine 1 μmol/L,and then were cultured for 30 min in morphine-free DMEM liquid culture medium before hypoxia.At 120 min of reoxygenation,the cells in 24-well plates were selected to detect the cell viability (by MTT),lactate dehydrogenase (LDH) activity in the culture medium,and cell apoptosis (by Hoechst 33234 staining).Apoptosis rate was calculated.Total RNA and protein were extracted from the cells in 60 mm dishes to detect the expression of miR-133b-5p and Fas mRNA (by quantitative real-time PCR) and Fas protein (by Western blot).Results Compared with C group,the cell viability was significantly decreased,LDH activity and apoptosis rate were increased,the expression of miR-133b-Sp was down-regulated,and the expression of Fas mRNA and protein was up-regulated in H/R group.Compared with H/R group,the cell viability was significantly increased,LDH activity and apoptosis rate were decreased,the expression of miR-133b-5p was up-regulatcd,and the expression of Fas mRNA and protein was down-regulated in MPC group.Conclusion The mechanism by which morphine preconditioning reduces H/R injury to rat cardiomyocytesis related to up-regulation of the expression of miR-133b-Sp and down-regulation of the expression of Fas.

Aim To evaluate the effects of morphine preconditioning ( MPC ) on the expression of microR-NAs ( miRNAs ) induced by hypoxia-reoxygenation (H/R) in H9c2 myocardial cells. Methods H9c2 cells were randomly divided into 3 groups ( n=4 each) as follows:control group ( CON) , hypoxia/ reoxygen-ation group ( H/R ) and morphine preconditioning group ( MPC+H/R) . The cells were cultured in nor-mal condition in CON group. The cells were subjected to 5 h hypoxia followed by 1 h reoxygenation in H/R group and MPC+H/R group. Specifically, the cells in MPC+H/R group were preconditioned with morphine with the final concentration of 1 μmol·L-1 for 10 min before H/R. After the treatment, CCK-8 was used to detect cell viability and chemical colorimetry was used to detect lactate dehydrogenase ( LDH ) activity in the culture medium. Cell apoptosis was assessed by An-nexin-V-FITC/PI flow cytometry. Relative expression of Fas protein was detected by Western blot. The ex-pression of miRNA in myocardial cells was analyzed by quantitative reverse transcription polymerase chain re-action ( qRT-PCR ) . Results Compared with CON group, the cell viability was significantly decreased, while the LDH activity, apoptotic rate and Fas protein expression were dramatically increased in group H/R (P<0. 01). However, MPC significantly increased the cell viability, whereas it decreased the LDH activity, apoptotic rate and Fas protein expression induced by H/R injury ( P < 0. 01 ) . The expressions of miR-133a-5p, miR-133b-5p, miR-664-1-5p, miR-6216 and let-7 e-5 p were markedly down-regulated by H/R as compared to CON group ( P <0. 05 ) , while MPC inhibited these miRNAs which were significantly down-regulated by H/R group ( P <0. 01 ) . Conclusion Morphine preconditioning might protect H9 c2 myocar-dial cells against H/R injury by regulating the expres-sion of miRNAs such as miR-133a-5p, miR-133b-5p, miR-664-1-5p, miR-6216 and let-7e-5p.

In view of the characteristics of the computerized system,the key points in the quality assurance (QA) of the computerized system was discussed and summarized combined with the requirements of the GLP laboratory in Europe and America.The validation of computerized system,the control during the use of computerized system,period maintenance and safety protection of computerized system,archives of electronic data was discussed,expecting to provide reference for the management of computerized system in Chinese GLP laboratory which is generally not high currently.The experiences were obtained as follow:Through repeated inspection and review,the problem was found and set as the risk point;a targeted QA inspection plan was made focusing on the risk-based inspection and the QA inspection plan was timely adjusted according to the problems,which ensures the pertinence and validity of the QA inspection.

Objective To systematically evaluate the clinical effect and safety of repaglinide and metformin for treating diabetes mellitus (MD) of secondary failure of sulfonylurea (SFS).Methods The randomized controlled trials (RCT) at home and abroad on the comparison of effect and safety of repaglinide and metformin in treating MD with SFS were retrieved.The modified Jadad scale was employed to evaluate the literature quality.The RevMan5.3.1 software was used for conducting the meta analysis.Results A total of 10 RCT were included.The meta-analysis results showed that compared with metformin for treating MA with SFS,repaglinide decreased the fasting blood glucose effectively (MD=-2.30,95 ％ CI:-2.53--2.06,P＜0.01),increased the fasting C-peptide (MD=0.06,95％CI:0.02-0.11,P=0.01),reduced the postprandial 2 h blood glucose (MD=-2.17,95 ％CI:-2.44-1.89,P＜0.01) and decreased glycosylated hemoglobin (MD=-2.60,95％CI:-3.21--2.00,P＜0.01) as well as the adverse reactions (RR=0.05,95％CI:0.02-0.09,P＜0.01).However,there was no statistical difference in fasting insulin between the repaglinide and metformin groups (MD=0.18,95％CI:-0.18-0.54,P=0.32).Conclusion Currently evidences suggest that repaglinide is superior to metformin for treating MD with SFS.