抗心律失常肽与溶血磷脂酸对兔室性心律失常影响的研究

目的 探讨抗心律失常肽(antiarrhythmic petide 10,AAP10)和溶血磷脂酸(lysophosphatidic acid,LPA)对兔室性心律失常的影响及其作用机制.方法 24只新西兰大白兔随机分为正常对照组、LPA组和AAP10干预组,建立兔左心室楔形心肌块模型,同步记录楔形心肌块内、外膜心肌细胞动作电位和跨室壁心电图,程序电刺激起搏,记录室性心律失常发生率.通过免疫印迹技术(Western blot)检测三组心肌去磷酸化缝隙连接蛋白43(non-phosphorylated connexin 43,NPCx43)的变化,采用免疫荧光技术观察NP-Cx43的分布.结果 LPA组QT间期、动作电位复极90%时程(90%of duration of action potential,APD90)、跨室壁复极离散度(transmural repolarization dispersion,TDR)与对照组相比均明显增加(P＜0.01),同时多形性室性心动过速的诱发率也明显增加(62.5%比0,P＜0.01),并伴随NP-Cx43含量明显增加(P＜0.01);AAP10干预组与LPA组相比,QT间期、内膜APD90、TDR均明显缩小(P＜0.01),多形性室性心动过速的诱发率也明显降低(P＜0.05),NP-Cx43含量也明显下降(P＜0.01).三组之间总Cx43含量差异无统计学意义.结论LPA有明显致心律失常作用,其机制可能与引起NP-Gx43含量增加、抑制缝隙连接通道功能有关,而AAP10可以拮抗LPA引起的NP-Cx43含量增加,同时降低LPA所致室性心律失常的发生率,具有抗心律失常的保护作用.

Abstract：

Objective To investigate the effect and potential mechanism of lysophosphatidic acid (LPA) and antiarrhythmic peptide (AAP10) on rabbit ventricular arrhythmia. Methods Twenty-four rabbits were randomly divided into three groups (n =8 each): control group, LPA group and AAP10 + LPA group. Using arterially perfused rabbit ventricular wedge preparations, transmural ECG and action potentials from both endocardium and epicardium were simultaneously recorded in the whole process of all experiments with two separate floating microeletrodes. The incidence of ventricular arrhythmia post S1S2 stimulation was recorded. Protein levels of nonphosphorylated Cx43 and total Cx43 were evaluated by Western blot. The distribution of nonphosphorylated Cx43 was observed by confocal immunofluorescence microscopy. Results Compared with the control group, the QT interval, endocardial action potential duration, transmural repolarization dispersion (TDR) and incidence of ventricular arrhythmia were significantly increased and nonphosphorylated Cx43 expression was significantly upregulated in the LPA group. Compared with the LPA group, cotreatment with AAP10 can reduce the QT interval, endocardial action potential duration, TDR and incidence of ventricular arrhythmia (25.0% vs 62. 5%, P ＜ 0. 01 ) and downregulate nonphosphorylated Cx43. Conclusions LPA could promote the arrhythmia possibly by upregulating nonphosphorylated Cx43 and subsequent gap junction transmission inhibition. Gap junction enhancer AAP10 could attenuate the proarrhythmic effect of LPA probably by downregulating myocardial nonphosphorylated Cx43 expression.     

Effects of the infant stool color card screening program on 5-year outcome of biliary atresia in Taiwan

In Taiwan, a screening system using an infant stool color card to promote the early diagnosis of biliary atresia (BA) was established in 2002. This study aimed to investigate the 5-year outcome of BA before and after using the screening program. BA patients were divided into three cohorts according to their birth dates. The patients in cohort A (n = 89) were born before the stool card screening program (1990-2000); those in cohort B (n = 28) were screened by the stool card regional screening program (2002-2003); and those in cohort C (n = 74) were screened by the stool card universal screening program (2004-2005). The relative odds ratios were computed using logistic regression to compare the different factors affecting survival time. The rate of age at Kasai operation <60 days was 49.4% and 65.7% in cohorts A and B+C, respectively (P = 0.02). The jaundice-free (total serum bilirubin <2.0 mg/dL) rate 3 months after surgery was 34.8% and 60.8% in cohorts A and B+C, respectively (P < 0.001). The 3-year jaundice-free survival rate with native liver was 31.5% in cohort A and 56.9% in cohort B+C (P < 0.001), whereas the 3-year overall survival rates were 64.0% and 89.2%, respectively (P < 0.001). The 5-year jaundice-free survival rate with native liver was 27.3% in cohort A and 64.3% in cohort B (P < 0.001), and the 5-year overall survival rates were 55.7% and 89.3%, respectively (P < 0.001). CONCLUSION: The stool color card screening program for BA allows for earlier Kasai operation, which increases the jaundice-free rate at 3 months postsurgery. With higher surgical success rates, the 3- and 5-year outcome of BA patients in Taiwan improves remarkably.     

Ginsenoside-Rg1 enhances angiogenesis and ameliorates ventricular remodeling in a rat model of myocardial infarction

Ginsenoside-Rg1 (Rg1) has been used in the traditional Chinese medicine for over 2,000?years. The present study was performed to test our hypothesis that Rg1 provides pro-angiogenic and anti-fibrotic benefits in the ischemic myocardium in a rat model of myocardial infarction. The expression of vascular endothelial growth factor (VEGF) and phosphorylation/activation of PI3K, Akt, and p38 MAPK signaling pathways were examined in human umbilical vein endothelial cells and in the myocardial samples of rats. In addition, the expression levels of TNF-?? and collagen I level, the number of newly formed blood vessels, the extent of myocardial fibrosis, and left ventricular function were measured in vivo. Our results demonstrated that administration of Rg1 increased VEGF expression levels, activated PI3K/Akt, and inhibited p38 MAPK in vitro and in vivo. Furthermore, Rg1 increased the density of newly formed vessels, decreased TNF-?? and collagen I expression levels and area of myocardial fibrosis, and improved left ventricle function in vivo. PI3K inhibitor LY294002 significantly attenuated Rg1-enhanced VEGF expression and capillary density. As well, inhibition of p38 MAPK slightly increased VEGF expression in vitro and in vivo, increased capillary density, and decreased TNF-?? and collagen I expression levels and area of myocardial fibrosis in vivo. Rg1-induced activation of PI3K/Akt also contributed to the downregulation of p38 MAPK. Thus, Rg1 is effective in promoting angiogenesis and attenuating myocardial fibrosis, resulting in ameliorated left ventricular function. The possible mechanisms may involve activation of PI3K/Akt, inhibition of p38 MAPK, and cross talk between the two signaling pathways.     

CASP3和 CASP9基因多态性与胃癌遗传易感性的关联研究

目的 探讨凋亡相关基因caspase 3 (CASP3)、caspase 9 (CASP9)单核苷酸多态性与胃癌遗传易感性的关系.方法 采用以自然人群为基础的病例对照研究设计,对278例胃癌患者和以同年龄(± 5岁)、同性别、同居住地匹配为原则获得的278名对照进行研究.CASP3 rs12108497和 CASP9 rs4646018多态位点的基因分型采用聚合酶链反应-限制性片段长度多态性的方法分析.非条件Logistic回归分析计算基因多态与胃癌风险的相关性.结果 携带 CASP3 rs12108497 TC、CC基因型者患胃癌的风险较TT基因型者分别增加45%(OR=1.45,95%CI:1.01～2.07)和117% (OR=2.17,95%CI:1.15～4.08).未发现 CASP9 rs4646018基因多态与胃癌发病风险间存在显著关联.多基因模型显示携带1个或2个风险基因型的个体胃癌易感性增高(OR=1.60,95%CI:1.12～2.30).分层分析表明,携带1个或2个风险基因型的个体罹患胃癌的危险度在男性个体(OR=1.62,95%CI:1.05～2.49)、吸烟者(OR=1.87,95%CI:1.12～3.12)、饮酒者(OR=1.92,95%CI:1.02～3.65)和无肿瘤家族史者(OR=1.78,95%CI:1.18～2.68)中尤为明显.结论 CASP3 rs12108497 多态性会增加胃癌的发病风险.CASP9 rs4646018多态性与胃癌发病风险无关.

Abstract：

Objective To investigate the association between the apoptosis genes CASP3 (rs12108497) and CASP9 (rs4646018) polymorphisms and the risk of developing stomach cancer. Methods In this population-based case-control study, 278 cases with stomach cancer and 278 age (±5 years), gender, and residential area matched controls were recruited. The genotypes were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The unconditional Logistic regression analysis was utilized to calculate the odds ratios (OR) and 95% confidence intervals (CI). Results The individuals with TC, CC genotypes of rs12108497 locus had significantly increased risk of stomach cancer in comparison to those carrying TT genotype (OR=1.45, 95% CI: 1.01-2.07 for TC; OR=2.17, 95%CI: 1.15-4.08 for CC). However, the rs4646018 locus of CASP9 gene polymorphism was not related to stomach cancer risk. Compared with the subjects carrying the both low-risk genotypes, those carrying 1 or 2 high-risk genotypes had a noteworthy increased risk of stomach cancer (OR=1.60, 95% CI: 1.12-2.30). The combined high-risk genotypes appeared to be more evident in subjects of male (OR=1.62, 95% CI: 1.05-2.49), ever-smokers (OR=1.87, 95%CI: 1.12-3.12), ever-drinkers (OR=1.92, 95%CI:1.02-3.65) and no family history of cancer (OR=1.78, 95%CI: 1.18-2.68). Conclusion The current findings suggest that the polymorphism of CASP3 rs12108497 might be associated with the risk of stomach cancer. However, the CASP9 rs4646018 polymorphism may not be related to the stomach cancer risk.     

A selective cysteinyl leukotriene receptor 2 antagonist blocks myocardial ischemia/reperfusion injury and vascular permeability in mice

Cysteinyl leukotrienes (CysLTs) are potent inflammatory mediators that predominantly exert their effects by binding to cysteinyl leukotriene receptors of the G protein-coupled receptor family. CysLT receptor 2 (CysLT(2)R), expressed in endothelial cells of some vascular beds, has been implicated in a variety of cardiovascular functions. Endothelium-specific overexpression of human CysLT(2)R in transgenic mice (hEC-CysLT(2)R) greatly increases myocardial infarction damage. Investigation of this receptor, however, has been hindered by the lack of selective pharmacological antagonists. Here, we describe the characterization of 3-(((3-carboxycyclohexyl)amino)carbonyl)-4-(3-(4-(4-phenoxybutoxy)phenyl)-propoxy)benzoic acid (BayCysLT(2)) and explore the selective effects of this compound in attenuating myocardial ischemia/reperfusion damage and vascular leakage. Using a recently developed β-galactosidase-β-arrestin complementation assay for CysLT(2)R activity (Mol Pharmacol 79:270-278, 2011), we determined BayCysLT(2) to be ～20-fold more potent than the nonselective dual CysLT receptor 1 (CysLT(1)R)/CysLT(2)R antagonist 4-(((1R,2E,4E,6Z,9Z)-1-((1S)-4-carboxy-1-hydroxybutyl)-2,4,6,9-pentadecatetraen-1-yl)thio)benzoic acid (Bay-u9773) (IC(50) 274 nM versus 4.6 μM, respectively). Intracellular calcium mobilization in response to cysteinyl leukotriene administration showed that BayCysLT(2) was >500-fold more selective for CysLT(2)R compared with CysLT(1)R. Intraperitoneal injection of BayCysLT(2) in mice significantly attenuated leukotriene D(4)-induced Evans blue dye leakage in the murine ear vasculature. BayCysLT(2) administration either before or after ischemia/reperfusion attenuated the aforementioned increased myocardial infarction damage in hEC-CysLT(2)R mice. Finally, decreased neutrophil infiltration and leukocyte adhesion molecule mRNA expression were observed in mice treated with antagonist compared with untreated controls. In conclusion, we present the characterization of a potent and selective antagonist for CysLT(2)R that is useful for discerning biological activities of this receptor.     

Association of genetic variants in CFTR gene, IVS8 c.1210-12T[5_9] and c.1210-35_1210-12GT[8_12], with spermatogenetic failure: case-control study and meta-analysis

It has been proposed that the genetic variants of IVS8 c.1210-12T[5_9] and adjacent c.1210-35_1210-12GT[8_12] in cystic fibrosis transmembrane conductance regulator gene might contribute to the spermatogenetic failure, but numerous genetic association studies that aimed to test this hypothesis reported conflicting results. So, in order to clarify such inconsistencies, we first conducted an original case-control study in Chinese Han population that consisted of 126 non-obstructive azoospermia, 169 severe oligospermia and 213 fertile male controls, and subsequently performed a meta-analysis of the available data, including our results. Our case-control study revealed that the frequencies of the T[5] allele and the T[5]+GT[12] combination in patients with non-obstructive azoospermia were both significantly higher than those in the fertile controls (13.1 versus 2.8%, P<0.01; 97.0 versus 41.7%, P<0.01, respectively), thus indicating a high risk susceptibility to non-obstructive azoospermia for males with T[5] allele or T[5]+GT[12]. However, as for the patients with severe oligospermia, both the T[5] allele frequency and T[5]+GT[12] did not differ from that for the control subjects (4.4 versus 2.8%, P>0.01; 53.3 versus 41.7%, P>0.01, respectively). In addition, our meta-analysis showed a significant increased risk of non-obstructive azoospermia for males with T[5] allele [odds ratio (OR) 3.45, 95% confidence intervals (CI) 2.29-5.20, P=0.000] and T[5]+GT[12] (OR 7.57, 95% CI 2.53-22.65, P=0.000) compared with males carrying other alleles. By contrast, neither T[5] allele itself nor T[5]+GT[12] combination had any effects on the risk of severe oligospermia (OR 0.96, 95% CI 0.42-2.21, P=0.002; OR 1.33, 95% CI 0.64-2.76, P=0.447). On the basis of these results, it can be concluded that the T[5] allele itself, or in combination with GT[12] repeat, may increase the susceptibility risk of non-obstructive azoospermia, but not that of severe oligospermia.