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51.
目的:探讨二氮嗪对离体自发性高血压大鼠心脏缺血/再灌注心功能及心肌组织ERK和JNK表达的影响及可能机制。方法:雄性自发性高血压大鼠取心行Langendorff灌流。实验分为5组(n=6/组):对照组(Con)在平衡后继续灌流40min,全心缺血25min,复灌30min。其余各组除全心缺血前处理不同外,余均同对照组。缺血预处理组(IP)2次给予5min缺血+10min复灌,二氮嗪预处理组(DP)给予2次含50μmol·L-1二氮嗪的K-H液10min后给不含二氮嗪的K-H液5min,5-HD、5-HD+DP组则在平衡后给予10min150μmol·L-1线粒体KATP阻断剂5-HD,余同Con及DP组。结果:IP组及DP组复灌末左室发展压、+dP/dtmax和-dP/dtmax的恢复率均高于Con组(P<0.01),但两组左室舒张末期压恢复率低于Con组(P<0.01);5-HD能拮抗二氮嗪引起的心功能指标的改善。复灌末IP、DP及5-HD+DP组ERK表达增加。IP组及DP组心肌的JNK表达低于Con组(P<0.05),5-HD+DP组JNK表达显著高于DP组。结论:二氮嗪预处理对离体自发性高血压大鼠心肌缺血/再灌注损伤有保护作用,此保护作用可能与ERK的表达增加及JNK表达减少有关。 相似文献
52.
Ling Jiang Hong Weng Ming-Yue Chen Chao Zhang Xian-Tao Zeng 《Molecular biology reports》2014,41(7):4795-4801
There ?765G > C, ?1195G > A, and 8473T > C polymorphisms in cyclooxygenase-2 (COX-2) gene polymorphisms and periodontitis risk were investigated based on published studies; however, their results could not give a conclusive result. Hence, we performed this meta-analysis of six published studies with eight case–control studies including these three polymorphisms which searched from PubMed and Web of Science up to October 15th, 2013. Odds ratios (ORs) with corresponding 95 % confidence intervals (CIs) were calculated to evaluate the association between the three polymorphisms of COX-2 and periodontitis risk. The results from 2,580 periodontitis patients and 3,073 healthy controls showed that none of ?765G > C, ?1195G > A, or 8473T > C polymorphism was not associated with periodontitis susceptibility [Take ?765G > C for example: OR = 0.94, 95 % CI = (0.57–1.53) for C vs. G; OR = 2.34, 95 % CI = (0.72–7.62) for CC vs. GG; OR = 0.68, 95 % CI = (0.46–1.01) for CG vs. GG; OR = 0.81, 95 % CI = (0.52–1.27) for (CG+GG) vs. GG; OR = 2.57, 95 % CI = (0.80–8.29) for CC vs. (GG+CG)]. In subgroup analyses according to the type of periodontitis and ethnicity for ?765G > C and ?1195G > A, and deviations in Hardy–Weinberg equilibrium for ?765G > C, we only observe a boundary association between ?1195G > A polymorphism and Asian population. However, due to limitations of this meta-analysis, the results should treat with caution and we suggest the further researches should be carried out to verify our results. 相似文献
53.
Introduction
In response to the ongoing debate over the relationship between the use of statins and the risk of Parkinson''s disease (PD), we performed a systematic review and meta-analysis of observational studies to examine their association.Methods
We conducted a review of the literature using electronic databases supplemented by a manual search to identify potentially relevant case-control or cohort studies. Summary relative risk (RRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Sensitivity and subgroup analyses were also conducted.Results
Eleven studies (five case-control and six cohort) with a total of 3,513,209 participants and 21,011 PD cases were included. Statin use was associated with a lower risk of PD, with a summary RR of 0.81 (95% CI 0.71–0.92). Sensitivity analysis demonstrated the robustness of results. Subgroup analyses showed that neither study design nor study region significantly influenced the effect estimates. However, subgroup studies adjusted for age or sex had a greater inverse association than did unadjusted analyses (age-adjusted RR 0.75, 95% CI 0.60–0.95; age-unadjusted RR 0.86, 95% CI 0.75–0.99 and sex-adjusted RR 0.76, 95% CI 0.59–0.98; sex-unadjusted RR 0.85, 95% CI 0.79–0.92).Conclusions
Results of this systematic review suggest that statin use is associated with a reduced PD risk. However, randomized controlled trials and more observational studies should be performed before strong conclusions are drawn. 相似文献54.
Pushpamali WA De Zoysa M Kang HS Oh CH Whang I Kim SJ Lee J 《Fish & shellfish immunology》2008,24(3):294-307
Thioredoxin peroxidase (TPx), also named peroxiredoxin (Prx), is an important peroxidase, which can protect organisms against various oxidative stresses. Two TPxs were isolated from a disk abalone (Haliotis discus discus) cDNA library, named as AbTPx1 and AbTPx2, respectively. AbTPx1 and AbTPx2 consist of 1315 and 1045 bp full-length cDNA with 753 and 597 bp open reading frames encoding 251 and 199 amino acids, respectively. The TPx signature motif 1 (FYPLDFTFVCPTEI) and motif 2 (GEVCPA) were conserved in both AbTPx1 and AbTPx2 amino acid sequences. Purified recombinant abalone TPx fusion proteins catalyzed the reduction of H2O2 and butyl hydroperoxide in peroxidase assays. Furthermore, both AbTPx fusion proteins were shown to protect super-coiled DNA from damage by metal-catalyzed oxidation (MCO) in vitro. Escherichia coli cells transformed with AbTPx1 and AbTPx2 coding sequences in pMAL-c2x showed resistance to H2O2 at 0.8 mM concentration by in vivo H2O2 tolerance assay. AbTPx1 and AbTPx2 mRNA were constitutively expressed in gill, mantle, abductor muscle and digestive tract in a tissue specific manner. Additionally, both TPxs mRNA were up-regulated in gill and digestive tract tissues against H2O2 at 3h post injection. The results indicate that AbTPx1 and AbTPx2 gene expressions are induced by oxidative stress and their respective proteins function in the detoxification of different ROS molecules to maintain efficient antioxidant defense in disk abalone. 相似文献
55.
Freeman MM Seaman MS Rits-Volloch S Hong X Kao CY Ho DD Chen B 《Structure (London, England : 1993)》2010,18(12):1632-1641
Ibalizumab is a humanized, anti-CD4 monoclonal antibody. It potently blocks HIV-1 infection and targets an epitope in the second domain of CD4 without interfering with immune functions mediated by interaction of CD4 with major histocompatibility complex (MHC) class II molecules. We report here the crystal structure of ibalizumab Fab fragment in complex with the first two domains (D1-D2) of CD4 at 2.2?? resolution. Ibalizumab grips CD4 primarily by the BC-loop (residues 121-125) of D2, sitting on the opposite side of gp120 and MHC-II binding sites. No major conformational change in CD4 accompanies binding to ibalizumab. Both monovalent and bivalent forms of ibalizumab effectively block viral infection, suggesting that it does not need to crosslink CD4 to exert antiviral activity. While gp120-induced structural rearrangements in CD4 are probably minimal, CD4 structural rigidity is dispensable for ibalizumab inhibition. These results could guide CD4-based immunogen design and lead to a better understanding of HIV-1 entry. 相似文献
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