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991.
白藜芦醇预处理小鼠应激性损伤后心功能动态观察   总被引:1,自引:0,他引:1  
目的观察白藜芦醇预处理小鼠应激性损伤后心功能的动态变化。方法正常成年雄性昆明小鼠60只分为对照组、创伤组、创伤加白藜芦醇(10μmol/L)组,每组20只。Noble-Collip创伤仪建立非致死性创伤小鼠模型,应用高分辨小动物超声成像系统分别于创伤前(0 h)及创伤后5个时间点(12 h、24 h、36 h、48 h、60 h)进行超声心动图检查。结果 (1)对照组各时间点小鼠心功能比较,差异无统计学意义(P〉0.05)。(2)与创伤前比较,创伤组小鼠回心血量显著减少;左心室舒张末期容积在创伤后12 h达最低点,较创伤前下降了46.1%(P〈0.05);创伤刺激下小鼠心脏功能出现明显的代偿性改变,创伤后12 h心率达到高峰,增加幅度达32.9%(P〈0.05);心排血量在各时间点基本处于同一水平,射血分数和短轴缩短率较创伤前分别降低了16%和20%(P〈0.05);E/A比值和E峰减速时间较创伤前减少了36.8%和29.1%(P〈0.05)。(3)创伤加白藜芦醇组小鼠回心血量亦明显减少(P〈0.05),但较创伤组要轻;创伤后12 h,左心室舒张末期容积较创伤前下降了30.8%(P〈0.05);左心室射血分数和短轴缩短率较创伤前分别降低了8.4%和17.7%(P〈0.05);E/A比值和E峰减速时间较创伤前减少了24.6%和24.1%(P〈0.05)。结论白藜芦醇预处理可以显著改善应激性损伤后小鼠心功能,增强小鼠心脏代偿能力。  相似文献   
992.
Reactive oxygen species (ROS) attack guanine bases in DNA easily and form 8-hydroxydeoxyguanosine (8-OHdG),which can bind to thymidine rather than cytosine,based on which,the level of 8-OHdG is gen-erally regarded as a biomarker of mutagenesis conse-quent to oxidative stress.For example,higher levels of 8-OHdG are noted in Helicobacter pylori-associated chronic atrophic gastritis as well as gastric cancer.However,we have found that exogenous 8-OHdG can paradoxically reduce ROS production,attenuate thenuclear factor-κB signaling pathway,and ameliorate the expression of proinflammatory mediators such as interleukin (IL)-1,IL-6,cyclo-oxygenase-2,and induc-ible nitric oxide synthase in addition to expression of nicotinamide adenine dinucleotide phosphate oxidase (NOX)-1,NOX organizer-1 and NOX activator-1 in vari-ous conditions of inflammation-based gastrointestinal (GI) diseases including gastritis,inflammatory bowel disease,pancreatitis,and even colitis-associated carci-nogenesis.Our recent finding that exogenous 8-OHdG was very effective in either inflammation-based or oxidative-stress-associated diseases of stress-related mucosal damage has inspired the hope that synthetic 8-OHdG can be a potential candidate for the treatment of inflammation-based GI diseases,as well as the pre-vention of inflammation-associated GI cancer.In this editorial review,the novel fact that exogenous 8-OHdG can be a functional molecule regulating oxidative-stress-induced gastritis through either antagonizing Rac-guanosine triphosphate binding or blocking the signals responsible for gastric inflammatory cascade is introduced.  相似文献   
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Aim: Hepatocellular carcinoma (HCC) ranks as the third leading cause of cancer deaths worldwide. Hepatic resection is the mainstay of curative treatment for early stage HCC. Although c‐Jun N‐terminal kinase (JNK) activation contributes to hepatocyte proliferation and HCC development in mice, the extent of involvement of JNK in human HCC development is unknown. The aim of this study is to assess the predictive value of JNK for postoperative recurrence in HCC. Methods: From April 2005 to March 2008, 159 patients underwent curative resection for HCC. From the 159 patients, 20 patients each matched for age, gender and etiology were registered as three groups: (i) without recurrence (no recurrence group), (ii) with recurrence within one year after surgery (early recurrence group), and (iii) with recurrence at one year or more after surgery (late recurrence group) (a cross‐sectional control study). We investigated factors contributing to postoperative early and late phase recurrence. Results: Multivariate analysis using a Logistic regression model showed that JNK activity in non‐cancerous liver tissue was correlated with postoperative late recurrence. (P = 0.02, odds ratio; 5.79, 95% confidence interval [CI]; 1.33–25.36). Conclusions: JNK activity in non‐cancerous liver tissue is considered as a reliable predictive biomarker for post‐operative recurrence in HCC.  相似文献   
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Sparganosis in humans is an incidental infection and is known to be associated with eating insufficiently cooked meat of frogs and snakes or drinking unboiled stream water. Although it can involve various internal organs, pulmonary and pleural involvement due to sparganum is rare. Because we recently experienced two cases involving lung parenchyma and pleura that were misdiagnosed as bacterial pneumonia and lung cancer, we herein intend to present them in detail.  相似文献   
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Antibodies against non-structural protein 1 (NS1) are considered to be the most reliable indicator of a present or past infection by West Nile virus (WNV) in animals. In this study, an in-house competitive enzyme-linked immunosorbent assay (NS1-cELISA) utilizing baculovirus-expressed NS1 and monoclonal antibodies against NS1 was established for the detection of antibody responses to NS1 in WNV-infected animals. The assay was validated by the simultaneous detection of early antibody responses to NS1 and the structural envelope protein in animals infected with WNV, or inoculated with inactivated WNV. NS1-cELISA detected WNV antibodies at 6 days post-infection (dpi) in a WNV-infected rabbit (percent inhibition [PI] value of 84.0), and at 10 dpi in a WNV-infected chicken (PI value of 67.0). The NS1-cELISA was able to detect WNV antibodies in sera from all WNV-infected rabbits at 10 dpi (PI value of 79.2±18.0), and from three of four WNV-infected chickens at 14 dpi (PI value of 73.7±22.8). The results of this study demonstrate that the antibody response to NS1 is similar to that against envelope protein in WNV-infected rabbits and chickens, whereas animals inoculated with inactivated WNV develop antibody responses only to the envelope protein but not to NS1. The NS1-cELISA developed here has the potential to be a useful tool for monitoring WNV circulation (i.e., the prevalence of specific antibodies against WNV NS1), by assaying serum samples from regions in which an inactivated vaccine control strategy has been implemented.  相似文献   
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