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Zang GQ Zhou XQ Yu H Xie Q Zhao GM Wang B Guo Q Xiang YQ Liao D 《World journal of gastroenterology : WJG》2000,6(5):688-692
AIM:To study the effect of hepatocyte apoptosis and necrosis induced by TNF-alpha on the pathogenesis of acute severe hepatitis (ASH).METHODS:The model of ASH was prepared in D-galactosamine (GalN) sensitized BALB/c mice by injection of either endotoxin (ET) or tumor necrosis factor-alpha(TNF-alpha. Morphological changes of apoptotic hepatocytes were studied by both light and electron microscope and in site end labeling method (ISEL). Molecular biological changes of DNA ladder were observed by electrophoresis of extract from liver tissues. Biochemical changes were measured by alanine aminotransferase (ALT), aspartic aminotransferase (AST) and TNF-alpha. The relation between apoptosis and necrosis was evaluated simultaneously.RESULTS:The sequence of hepatocyte apoptosis, necrosis, and final death from ASH was observed both in GalN/ET and GalN/TNF-alpha group. Apoptosis was prominent at 3.5h and 6h after injection of inducer, while necrosis became dominant at 9h after challenge. The appearance of apoptosis was earlier in GalN/TNF-alpha group than that in GalN/ET group. Pretreatment of mice with antiTNF IgG1 may completely prevent the liver injury induced by GalN/ET.CONCLUSION:TNF-alpha can cause liver amage by inducing hepatic apoptosis and necrosis in mice with endotoxemia. 相似文献
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《Journal of the American College of Cardiology》2019,73(25):3295-3308
BackgroundAdvanced liver disease is known to increase the risk for bleeding and affects the hepatic clearance and metabolism of drugs. Subjects with active liver disease were excluded from pivotal clinical trials of direct oral anticoagulants (DOACs), so the evidence regarding the efficacy and safety of DOACs in patients with liver disease is lacking.ObjectivesThe aim of this study was to compare DOACs with warfarin in patients with nonvalvular atrial fibrillation and liver disease.MethodsUsing the Korean National Health Insurance Service database, subjects with atrial fibrillation and active liver disease treated with oral anticoagulation were included (12,778 with warfarin and 24,575 with DOACs), and analyzed ischemic stroke, intracranial hemorrhage, gastrointestinal bleeding, major bleeding, all-cause death, and the composite outcome. Propensity score weighting was used to balance covariates between the 2 groups.ResultsDOACs were associated with lower risks for ischemic stroke (hazard ratio [HR]: 0.548; 95% confidence interval [CI]: 0.485 to 0.618), intracranial hemorrhage (HR: 0.479; 95% CI 0.394 to 0.581), gastrointestinal bleeding (HR: 0.819; 95% CI: 0.619 to 0.949), major bleeding (HR: 0.650; 95% CI: 0.575 to 0.736), all-cause death (HR: 0.698; 95% CI: 0.636 to 0.765), and the composite outcome (HR: 0.610; 95% CI: 0.567 to 0.656) than warfarin. Among the total study population, 13% of patients (n = 4,942) were identified as having significant active liver disease. A consistent benefit was observed in patients with significant active liver disease (HR for the composite outcome: 0.691; 95% CI: 0.577 to 0.827).ConclusionsIn this large Asian population with atrial fibrillation and liver disease, DOACs showed better effectiveness and safety than warfarin, which was consistent in those with significant active liver disease. 相似文献
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目的观察分析南京市某有机磷农药生产企业人员外周血象(包括WBC、PLT、RBC和Hb)、丙氨酸转氨酶(ALT)和胆碱酯酶(CHE)结果的变化情况,探讨不同工种、不同工龄、不同性别与研究指标之间的关系,为减少职业危害提供科学依据。方法对2013年某有机磷农药生产企业1 138名人员和某外厂692名未接触有机磷农药的工人进行外周血象、ALT和CHE检测分析。结果有机磷组的WBC为(6.0±1.47)×10^9/L,PLT为(158.2±52.29)×10^9/L,RBC为(4.59±0.49)×10^12/L,Hb为(137.3±15.93)g/L,ALT为(24.9±19.78)U/L,CHE为(248.3±85.43)U/L,均在正常参考范围内;但WBC、PLT、RBC、Hb和CHE均低于对照组,差异有统计学意义(均P〈0.01)。不同工种间,PLT、Hb、RBC、ALT和CHE的差异有统计学意义(P〈0.01),操作工的WBC为(5.97±1.47)×10^9/L,PLT为(155.7±51.55)×10^9/L,RBC为(4.58±0.49)×10^12/L,Hb为(137.1±16.0)g/L,ALT为(24.1±17.33)U/L,CHE为(236.3±86.06)U/L,均低于管理人员,差异均有统计学意义。随着接害工龄的增加,血液检查的各项指标有逐渐降低的趋势,其中,5-15 a组的CHE为(213.6±83.85)U/L,RBC(4.49±0.52)×10^12/L,Hb为(133.9±16.99)g/L,显著低于〈5 a组,差异有统计学意义。CHE的异常率在性别间差异有统计学意义。结论长期接触有机磷农药对生产工人的外周血象,ALT和CHE有一定的负面影响,对工龄5-15年的影响尤为明显。 相似文献
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目的目前ALT持续正常(PNALT)以及持续或间断升高(PIEALT)的慢性乙型肝炎(CHB)患者肝脏硬度值(LSM)的数据十分有限。本研究对该组患者LSM范围及其影响因素进行了探讨,以供临床应用参考。方法将在2012年9月-2013年3月于本院就诊的208例初治CHB患者纳入研究,均接受瞬时弹性扫描仪(FS)检查。PNALT组:在最近1 a随访至少3次,每次间隔2个月以上,ALT水平均正常,入组时ALT正常;PIEALT组进一步分为ALT轻度升高(过去1 a随访中ALT水平至少有1次升高但2×ULN)以及ALT明显升高(过去1 a随访中ALT水平至少有1次升高2×ULN),入组时ALT2×ULN。根据现有的研究结果,当ALT2×ULN时,用于诊断以及排除进展性肝纤维化的标准分别为LSM≥10.6 kPa和LSM7.4 kPa。计量资料分析采用t检验、方差分析和秩和检验,计数资料采用χ2检验,相关因素采用双变量相关分析及Logistic回归分析。结果受试人群平均LSM为(6.2±2.9)kPa。在PNALT患者中,LSM≥7.4 kPa占14.3%(18/126),LSM≥10.6 kPa占2.4%(3/126)。在总体PIEALT患者中,这个比例分别是35.4%(29/82)以及13.4%(11/82)。多元回归分析中,ALT1×ULN(OR=2.63,P=0.037)、男性(OR=5.29,P=0.012)是LSM≥7.4 kPa的独立影响因素;HBV DNA定量5 log10拷贝/ml是LSM≥10.6 kPa唯一的独立影响因素(OR=13.84,P=0.046)。结论在PIEALT和PNALT的CHB患者中,分别有35%及14%的患者不能排除进展性肝纤维化的可能;大约13%的PIEALT患者根据LSM结果可判断为进展性肝纤维化。对于ALT1×ULN、HBV DNA拷贝数的对数值大于5的男性CHB患者,建议对其进行密切随访。 相似文献
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Mitchell L. Jones Christopher J. Martoni Sandeep Tamber Mathieu Parent Satya Prakash 《Food and chemical toxicology》2012
Probiotic organisms have shown promise in treating diseases. Previously, we have reported on the efficacy of microencapsulated Lactobacillus reuteri NCIMB 30242 in a yogurt formulation at lowering serum cholesterol levels in otherwise healthy hypercholesterolemic adults. This study investigates the safety and toxicology of oral ingestion of microencapsulated L. reuteri NCIMB 30242 in a yogurt formulation. A randomized group of 120 subjects received a dose of 5 × 1010 CFU microencapsulated L. reuteri NCIMB 30242 in yogurt (n = 59) or placebo yogurt (n = 61) twice/day for 6 weeks. Clinical chemistry and hematological parameters of safety were analyzed. Fecal samples were collected at these time points for the analysis of deconjugated bile acids. The frequency, duration and intensity of adverse events (AEs) and clinical significance of safety parameters were recorded for both groups. No clinically significant differences between the probiotic yogurt and placebo yogurt treated groups were detected in either the blood clinical chemistry or hematology results and there was no significant increase in fecal deconjugated bile acids (P > 0.05) between treated and control groups. The frequency and intensity of AEs was similar in the two groups. These results demonstrate the safe use of this formulation in food. 相似文献
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Selective impairment of drug-metabolizing enzymes in pig liver during subchronic dietary exposure to aflatoxin B1. 总被引:1,自引:0,他引:1
Guylaine M Meissonnier Joelle Laffitte Nicolas Loiseau Etienne Benoit Isabelle Raymond Philippe Pinton Anne-Marie Cossalter Gérard Bertin Isabelle P Oswald Pierre Galtier 《Food and chemical toxicology》2007,45(11):2145-2154
Consequences of subchronic exposure to aflatoxin B1 (AFB1) on liver monooxygenase and transferase enzymes were compared in control pigs and pigs given 385, 867 or 1,807 microg AFB1/kg of feed for 4 weeks. Animals exposed to the highest dose of toxin developed clinical signs of aflatoxicosis, like liver fibrosis, hepatic dysfunction and decreased weight gain. This group had significantly lower levels of liver cytochrome P450, ethoxyresorufin O-deethylase (EROD) activity, testosterone metabolism, P450 1A and P450 3A protein expression. By comparison, mild degenerative hepatic changes, no hepatic dysfunction but a similar pattern of liver P450 enzymes activity without changes in P450 3A expression were observed in pigs exposed to 867 microg AFB1/kg of feed. Benzphetamine and aminopyrine N-demethylase activities were increased in pigs exposed to 867 or 1,807microg AFB1/kg of feed. Pigs exposed to 385 microg AFB1/kg of feed had low levels of EROD activity and all other biotransformation and clinical parameters remained at control levels. Aniline hydroxylase activity, P450 2C protein expression, UDP-glucuronosyl and glutathione S-transferase activities were unaffected at all doses of AFB1. In conclusion, P450 1A and P450 3A appear to be specific targets of AFB1 even if pig did not display clinical sign of liver toxicosis. 相似文献