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991.
目的:分析p53基因单核苷酸多态性(SNPs)位点的多态性,探究云南汉族非综合征性唇腭裂与p53基因的相关性。方法:选取2016年1月-2018年12月于笔者医院就诊的非综合征性唇腭裂患儿100例为试验组,选取医院同期无先天性畸形正常患儿100例为对照组。采用Taqman探针荧光定量PCR法对p53基因的SNPs位点rs12947788和rs1042522进行基因分型,并用χ^2检验和Logistic回归分析多态位点与非综合征性唇腭裂的相关性。结果:p53的基因SNPs位点rs12947788的等位基因变体A携带者(AA+GA vs GG)发生非综合征性唇腭裂的风险增加(OR=1.393,95%CI 1.030~1.884,P=0.032)。rs1042522(CC vs CG+GG)增加吸烟者母亲生下NSCL/P患儿的风险(OR=2.561,95%CI=1.146~5.721,P=0.022)。rs12947788(AA+GA vs GG)可明显增加有饮酒史母亲(OR=3.235,95%CI=1.158~9.040,P=0.025)生下NSCL/P患儿的风险。结论:云南汉族人群非综合征性唇腭裂与p53基因rs1042522、rs12947788多态具有一定的相关性。 相似文献
992.
目的:探讨蓝萼乙素对三阴性乳腺癌MDA-MB-231细胞增殖、迁移及侵袭的影响及其作用机制。方法:体外培养人乳腺癌细胞MDA-MB-231,加入不同浓度(0、2、4、8μmol/L)蓝萼乙素干预处理,采用MTT法检测细胞增殖能力;划痕实验考察细胞迁移能力;Transwell小室法考察细胞侵袭能力;Western blotting法检测细胞内p38MAPK、p-p38MAPK、FOXO3a及上皮-间质转化(EMT)相关标志物(E-cadherin、Vimentin及N-cadherin)的表达水平。结果:蓝萼乙素浓度为2、4、8μmol/L时,细胞增殖率分别为(83.2±6.90)%、(70.72±6.53)%、(45.43±7.51)%,较空白对照组[(100.00±7.84)%]降低;细胞侵袭数量分别为(300.54±24.91)、(255.44±23.59)、(208.66±36.18),较空白对照组(368.44±28.32)降低;细胞迁移距离分别为(487.11±53.00)μm、(394.93±61.91)μm、(312.88±35.42)μm,较空白对照组[(559.37±75.77)μm]降低;p-p38MAPK表达量分别为(1.38±0.11)、(1.69±0.13)、(2.23±0.19),较空白对照组(1.00±0.09)增加;FOXO3α表达量分别为(1.40±0.16)、(1.97±0.31)、(2.44±0.26),较空白对照组(1.00±0.18)增加;E-cadherin表达量分别为(1.15±0.11)、(1.77±0.22)、(1.86±0.15),较空白对照组(1.00±0.11)增加;Vimentin表达量分别为(0.86±0.04)、(0.49±0.05)、(0.54±0.04),较空白对照组(1.00±0.04)减少;N-cadherin表达量分别为(0.66±0.07)、(0.58±0.08)、(0.42±0.04),较空白对照组(1.00±0.12)减少,差异均有统计学意义(P 0.05)。结论:蓝萼乙素可通过介导p38MAPK/FOXO3a信号传导有效干扰肿瘤细胞EMT进程,发挥其抑制三阴性乳腺癌细胞增殖、迁移及侵袭的作用。 相似文献
993.
994.
M. CATTANEO 《Journal of thrombosis and haemostasis》2007,5(S1):230-237
Summary. The definition 'resistance to antiplatelet drugs' should be limited to situations in which failure of the drug to hit its pharmacological target has been documented by specific laboratory tests. Aspirin resistance, as determined by specific tests (e.g. serum thromboxane B2 ), appears to be rare (1–2%) and, in most instances, is caused by poor compliance. In contrast to aspirin, studies that used specific tests to measure the pharmacological effect of thienopyridines [e.g. vasodilator-stimulated phosphoprotein (VASP)] showed a wide variability of responses to these drugs, with significant proportions of subjects (15–30%) who are very poor responders. Inter-individual differences in the extent of metabolism of thienopyridines to their active metabolites is the most plausible mechanism for the observed inter-individual variability in platelet inhibition. The demonstration that some patients may be 'resistant' or 'poor responders' to the pharmacological effect of antiplatelet drugs, has prompted the need of laboratory monitoring of antiplatelet therapy. However, many published studies have been performed using unspecific tests of platelet function, which identify patients on antiplatelet treatment with high residual platelet reactivity, which is not necessarily because of resistance to antiplatelet drugs. Despite this drawback, identification of patients with high residual platelet reactivity may be useful to predict their risk of atherothrombotic events. However, many studies still need to be carried out to identify the ideal laboratory test and to answer basic questions on its clinical utility and cost-effectiveness, before monitoring antiplatelet therapy can be recommended in the clinical practise. Until then, monitoring of antiplatelet therapy should be considered for investigational purposes only. 相似文献
995.
目的研究细胞色素P450(CYP)2D6*10多态性对患者手术后应用曲马多止痛后体内曲马多药动学特征的影响。方法45例患者于手术后首次静脉注射曲马多100mg,随后采用LC—Ms法测定曲马多及其代谢物O-去甲基曲马多(M1)的血浆浓度,采用非房室模型法计算曲马多和M1的主要药动学参数(AUC、CL、t1/2、MRT、ρmax和tmax)。采用聚合酶链反应一限制性片段长度多态性(PCR.RFLP)技术检测患者的CYP2D6*10基因型,即野生型、杂合子和突变型。结果45例患者中CYP2D6*10等位基因的发生频率为51%。与野生型比较,突变型患者体内曲马多的t1/2、MRT延长,AUC增大,CL减少(P均〈0.05)。结论CYP2D6*10基因多态性对术后患者体内曲马多的药动学特征有显著影响。 相似文献
996.
目的:考察CYP2C19、P2Y12受体的基因多态性与氯吡格雷抵抗的相关性研究.方法:96例中国缺血性脑卒中患者持续服用氯吡格雷75 mg,收集全血提取DNA,采用Sequenom MassARRAY iPLEX(R)基因型分析技术进行CYP2C19* 2(681G>A,rs4244285)、CYP2C19*3(636 G>A,rs4986893)及P2Y12受体(52G>T,rs6809699) (744T>C,rs2046934)4个SNPs的基因型分析.采用二磷酸腺苷(ADP)诱导光比浊法测定血小板聚集功能.采用Chi-square检验或Fisher确切概率法分析相关性.结果:患者分为氯吡格雷抵抗(CR)组与非抵抗组,CYP2C19* 2(rs4244285)及P2Y12受体(rs2046934)基因型分布在两组间的差异有统计学意义(P=0.027,P=0.034).其中,CYP2C19*2 GA+ AA基因型为CR发生的风险因素(OR=2.607,95%CI:1.062~6.399).CYP2C19*3(rs4986893)及P2Y12受体(rs6809699)基因型分布在两组比较中差异无统计学意义(P>0.05).结论:在中国缺血性脑卒中患者中,CYP2C19*2(rs4244285) GA+ AA型与氯吡格雷抵抗的发生密切相关,该基因型检测将有助于指导氯吡格雷的临床合理应用. 相似文献
997.
目的探讨氯吡格雷干预对血小板聚集及脓毒症心肌损伤的影响及脓毒症时心肌损伤与血小板的聚集的关系。方法取Wistar雄性大鼠72只,随机分成3组:正常对照组(NC组),内毒素组(ET组),氯吡格雷+内毒素组(CL+ET组)。CL+ET组预先给予氯吡格雷3 d后,腹腔注射LPS(10 mg·kg-1)建立急性脓毒症心肌损伤模型。在0、6、12 h采血检测血小板聚集率、心肌肌钙蛋白I(cTnI);酶联免疫吸附测定法(ELISA)检测血清、心肌中TNF-α的表达水平;检测心脏干湿重比;取心肌标本,行HE染色,光镜观察大鼠心肌结构改变。结果与NC组相比,注射LPS后ET组血小板聚集率更高(P〈0.05),且随时间延长而增加[(27.78±1.01)、(32.41±3.04)、(50.99±14.35)ohm];CL+ET组预先给予氯吡格雷处理后,血小板聚集率处于抑制状态(P〈0.05)。CL+ET组较ET组,在相应时点对内毒素诱导的cTnI、血清及心肌TNF-α水平升高有明显的抑制作用(P〈0.05);心肌干湿重比有差异(P〈0.05)。ET组LPS注射6 h后心肌出现炎症细胞浸润、纤维肿胀、排列紊乱,12 h最显著;与ET组比较,CL+ET组在相应时点对心肌炎症细胞浸润和心肌纤维肿胀程度减轻。结论 LPS引起的心肌损伤过程中血小板聚集明显,氯吡格雷阻断血小板P2Y12受体,抑制血小板聚集,对LPS引起的心肌损伤具有一定的抑制作用。 相似文献
998.
《Environmental toxicology and pharmacology》2014,37(3):989-996
Benzo[a]pyrene (BaP) is a human carcinogen requiring metabolic activation prior to reaction with DNA. Cytochrome P450 (CYP) 1A1 is the most important hepatic and intestinal enzyme in both BaP activation and detoxification. CYP1A2 is also capable of oxidizing BaP, but to a lesser extent. The induction of CYP1A1/2 by BaP and/or β-naphthoflavone in liver and small intestine of rats was investigated. Both BaP and β-naphthoflavone induced CYP1A expression and increased enzyme activities in both organs. Moreover, the induction of CYP1A enzyme activities resulted in an increase in formation of BaP–DNA adducts detected by 32P-postlabeling in rat liver and in the distal part of small intestine in vivo. The increases in CYP1A enzyme activity were also associated with bioactivation of BaP and elevated BaP–DNA adduct levels in ex vivo incubations of microsomes of both organs with DNA and BaP. These findings indicate a stimulating effect of both compounds on BaP-induced carcinogenesis. 相似文献
999.
Jin-dong Qin Zhi-hong Cao Xue-feng Li Xiao-lin Kang Yan Xue Yue-ling Li 《Pharmaceutical biology》2014,52(11):1460-1466
Context: Ammonium pyrrolidine dithiocarbamate (PDTC) is a potent inhibitor of nuclear factor-κB (NF-κB). Recent studies have shown that NF-κB plays an essential role in the regulation of genes whose products are involved in the pathogenesis of immunological liver injury.Objective: To study the function of NF-κB in immunological liver injury of rat model and its effect on CYP2E1 content and metabolic activity.Materials and methods: The present study investigated the effect of passivating NF-κB activation on CYP2E1 using Bacillus calmette Guérin (BCG)-induced immunological liver injury in Sprague–Dawley rats measured in terms of enzyme levels. The degree of hepatic injury of rats was measured by using biochemical parameters, hepatic tissue pathological changes, and physiological parameters. Protein localization of liver NF-κB was detected by immunohistochemical assay. Western blot analysis was used to detect the protein expression of NF-κB, IκBα, iNOS, and CYP2E1. The content of CYP2E1 of homogenate in the rat liver was detected by ELISA assay and the enzyme kinetics of CYP2E1 probe drug chlorzoxazone was evaluated by high-performance liquid chromatography (HPLC) assay.Results: The results showed that BCG-pretreatment (125?mg/kg) significantly (p?0.01) increased the weight of liver and spleen (increased by 70% and 248%, respectively), serum levels of alanine transarninase (ALT) and aspartate aminotransferase (AST) (increased by 200% and 75.8%, respectively), the expression of NF-κB and iNOS (increased by 228% and 303%, respectively), and decreased CYP2E1 content and metabolic activity (p?0.05). Administration of PDTC (50, 100, and 200?mg/kg) reversed above hepatic injury stimulated by BCG in vivo. Moreover, PDTC (ED50: 76?mg/kg) dose dependently inhibited down-regulation of CYP2E1 (p?0.05).Conclusion: Passivation of NF-κB can inhibit the down-regulation of CYP2E1 and iNOS to induce in rat liver tissue with immunological liver injury; NF-κB may be involved in the CYP2E1 regulation through iNOS. 相似文献
1000.
Naoyuki Maeda Kanako Okumura Emi Tanaka Tomokazu Suzuki Taku Miyasho Satoko Haeno Hiromi Ueda Nobuhiko Hoshi Hiroshi Yokota 《Environmental toxicology》2014,29(12):1452-1459
Reproductive toxicities and endocrine disruptions caused by chemicals in adult males are still poorly understood. It is our objectives to understand further details of the initial adverse effects leading severe testicular toxicities of a pharmaceutical endocrine disruptor, diethylstilbestrol (DES). Downregulations of both testicular regulatory proteins, such as the steroidogenic acute regulatory protein (StAR) and the peripheral benzodiazepine receptor (PBR), which play important roles in the transport of cholesterol into the mitochondria, and cytochrome P450 mediating the cholesterol side chain cleavage reaction (P450scc), were observed in the rat orally administered DES (340 μg/kg/2 days) for 2 weeks. We found that after only 1 week treatment with DES, the blood and testicular testosterone (TS) levels were drastically decreased without abnormalities of the StAR and PBR; however, the protein and mRNA levels of P450scc were diminished. Decrease in the conversion rate of cholesterol to pregnenolone was delayed in the in vitro assay using the testicular mitochondrial fraction from the rat treated with DES for 1 week. When the precursors in TS biosynthesis containing the testis were identified and determined by liquid chromatography‐mass spectrometry analysis, decreased levels of all precursors except cholesterol were observed. In conclusion, suppressed cytochrome P450scc expression in adult male rat was identified as an initial target of DES in testicular steroidogenesis disorder leading reproductive toxicities. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1452–1459, 2014. 相似文献