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1.
Abstract: The importance of the bioactivation of 1-naphthylisothiocyanate was studied. Forty minutes after 1-naphthylisothiocyanate administration to rats, bile was collected over a 2.5-h period; the liver was then excised and homogenized. 1-naphthylisothiocyanate and its metabolites in bile and liver of rats were identified and quantified using coupled gas chromatography-mass spectrometry. Three main compounds were found in all 1-naphthylisothiocyanate-treated animals. They were identified as 1-naphthyl isocyanate, 1-naphthylamine and the parent compound, 1-naphthylisothiocyanate. When rats were given cycloheximide, which attenuates 1-naphthylisothiocyanate toxicity, 30 min before 1-naphthylisothiocyanate (300 mg/kg), 1-naphthyl isocyanate concentration was significantly lower than in rats receiving only 1-naphthylisothiocyanate. The appearance of 1-naphthylamine was also inhibited by cycloheximide, although not to the same extent as 1-naphthyl isocyanate. On the other hand, phenobarbital, which potentiates 1-naphthylisothiocyanate hepatotoxicity, enhanced 1-naphthyl isocyanate and 1-naphthylamine formation. It is suggested that 1-naphthyl isocyanate, 1-naphthylamine and the highly reactive sulfur released from 1-naphthylisothiocyanate might be involved in the hepatotoxic effect of 1-naphthylisothiocyanate.  相似文献   

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Amodiaquine (AQ) is a 4‐aminoquinoline widely used in the treatment of malaria as part of the artemisinin combination therapy (ACT). AQ is metabolised towards its main metabolite desethylamodiaquine mainly by cytochrome P450 2C8 (CYP2C8). CYP1A1 and CYP1B1 play a minor role in the metabolism but they seem to be significantly involved in the formation of the short‐lived quinine‐imine. To complete the genetic variation picture of the main genes involved in AQ metabolism in the Zanzibar population, previously characterised for CYP2C8, we analysed in this study CYP1A1 and CYP1B1 main genetic polymorphisms. The results obtained show a low frequency of the CYP1A1*2B/C allele (2.4%) and a high frequency of CYP1B1*6 (approximately 42%) followed by CYP1B1*2 (approximately 27%) in Zanzibar islands. Genotype data for CYP1A1 and CYP1B1 show a low incidence of fast metabolisers, revealing a relatively safe genetic background in Zanzibar’s population regarding the appearance of adverse effects.  相似文献   

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Aims and background: Hyperbilirubinemia is often observed in chronic hemolysis and results in the formation of pigment cholelithiasis that could be increased by the presence of defected enzymes involved in the bilirubin metabolism. Indeed, this is the first report that interested in the study of polymorphisms in genes encoded for enzymes involved in the bilirubin metabolism: rs 4149056 of SLCO1B1 and rs4149000 of SLCO1A2 in combination with rs8175347 and rs887829 of UGT1A1 in order to find a correlation between the polymorphisms studied and the presence of gallstones in a population of sickle cell anemia (SCA) pediatric Tunisians.

Material and methods: Our study involved 102 unrelated Tunisian subjects. All SCA patients are children (less than 16 years old) and were characterized by hyperbilirubinemia and 52 of them have cholelithiasis. The polymorphisms of the candidate genes were analyzed for all subjects by PCR/sequencing. Genotype and allele frequencies between cases and controls were compared using Pearson's chi-square test with a significance threshold of P?<?0.05 (compare 2, version 1.02).

Results: The novelty of this report is that children carrying the combined genotype of the rs studied: (TA7TA7)/TT/TC/GA have a higher risk to develop gallstones (P?=?0.0027, RR?=?18.27 (20.0061–915.28)).

Conclusion: Altogether our data provide the implication of UGT1A1 and SLCO1A2 in sickle cell anemia-related cholelithiasis.  相似文献   

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The 2009 H1N1 influenza A virus that has targeted not only those with chronic medical illness, the very young and old, but also a large segment of the patient population that has previously been afforded relative protection - those who are young, generally healthy, and immune naive. The illness is mild in most, but results in hospitalization and severe ARDS in an important minority. Among those who become critically ill, 20-40% will die, predominantly of severe hypoxic respiratory failure. However, and potentially in part due to the young age of those affected, intensive care with aggressive oxygenation support will allow most people to recover. The volume of patients infected and with critical illness placed substantial strain on the capacity of the health care system and critical care most specifically. Despite this, the 2009 pandemic has engaged our specialty and highlighted its importance like no other. Thus far, the national and global critical care response has been brisk, collaborative and helpful - not only for this pandemic, but for subsequent challenges in years ahead.  相似文献   

6.
PD-1(CD279)是一种负性协同刺激分子,属于CD28超家族成员,呈诱导性表达于活化的T、B和自然杀伤细胞表面.PD-L1(B7-H1,CD274)和PD-L2(B7-DC,CD273)是PD-1的两个配体.PD-1和PD-L1相互作用可以使活化的自身反应性T细胞获得负性信号,抑制其对自身抗原持续的免疫应答.若PD...  相似文献   

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目的分析泰安市2008~2009年度季节性流感与2009年度甲型H1N1流感病原学检测结果 ,比较季节性H1N1与甲型H1N1血凝素基因变异情况。方法选择国家级流感监测哨点医院以及暴发疫情的疫点,采集流感样病例的鼻咽拭子标本,通过RealtimePCR进行病毒检测,用MDCK细胞进行病毒分离,通过RT-PCR扩增血凝素HA1片段的基因并测序,利用生物信息学进行序列分析。结果 2008~2009年共检测鼻咽拭子标本283份,分离出流感病毒33株,分离阳性率为11.67%,其中季节性H1N1亚型31株。2009年5月1日~12月31日,检测鼻咽拭子标本996份,流感核酸检测阳性417份,阳性率为41.86%,其中甲型H1N1337份,季节性H1N1亚型1份。6株季节性H1N1病毒均在多个氨基酸位点上发生变异,与疫苗株A/Brisbane/59/2007(H1N1)比较,有11个位点发生了突变,其中5个位点位于抗原决定簇上;测序成功的6株甲型H1N1病毒在多个氨基酸位点发生变异,与疫苗株A/California/07/2009(H1N1)比较,有6个位点发生突变,其中1个位点位于抗原决定簇的B区。结论 2008~2009年度季节性H1N1为优势株,甲流暴发后,甲型H1N1成为绝对优势毒株。季节性H1N1分离株有多处氨基酸替换,抗原决定簇B区变异频繁;甲型H1N1病毒分离株的基因有变异,但关键位点第222位仍为D(天冬氨酸),与疫苗株相比抗原决定簇的关键位点变化不大。  相似文献   

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Abstract:  Administration of melatonin to rodents decreases the incidence of tumorigenesis initiated by benzo[ a ]pyrene or 7,12-dimethylbenz[ a ]anthracene, which requires bioactivation by cytochrome P450 enzymes, such as CYP1A1, CYP1A2 and CYP1B1, to produce carcinogenic metabolites. The present study tested the hypothesis that melatonin is a modulator of human CYP1 catalytic activity and gene expression. As a comparison, we also investigated the effect of melatonin on the catalytic activity of CYP2A6, which is also a procarcinogen-bioactivating enzyme. Melatonin (3–300 μ m ) decreased 7-ethoxyresorufin O -dealkylation catalyzed by human hepatic microsomes and recombinant CYP1A1, CYP1A2 and CYP1B1, whereas it did not affect coumarin 7-hydroxylation catalyzed by hepatic microsomes or recombinant CYP2A6. Melatonin inhibited CYP1 enzymes by mixed inhibition, with apparent K i values (mean ± S.E.M.) of 59 ± 1 (CYP1A1), 12 ± 1 (CYP1A2), 14 ± 2 (CYP1B1) and 46 ± 8 μ m (hepatic microsomes). Additional experiments indicated that melatonin decreased benzo[ a ]pyrene hydroxylation catalyzed by hepatic microsomes and CYP1A2 but not by CYP1A1 or CYP1B1. Treatment of MCF-10A human mammary epithelial cells with melatonin (up to 300 μ m ) did not affect basal or benzo[ a ]pyrene-inducible CYP1A1 or CYP1B1 gene expression. Consistent with this finding, melatonin did not influence reporter activity in aryl hydrocarbon receptor-dependent pGudluc6.1-transfected MCF-10A cells treated with or without benzo[ a ]pyrene, as assessed in an in vitro cell-based luciferase reporter gene assay. Overall, melatonin is an in vitro inhibitor of human CYP1 catalytic activity, and it may be useful to develop potent analogues of melatonin as potential cancer chemopreventive agents that block CYP1-mediated chemical carcinogenesis.  相似文献   

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目的通过对甲型H1N1流感合并肺炎的临床特点的分析。方法分析2009年月10月-2010年3月在我院入住的29例甲型H1N1流感合并肺炎患者的临床表现、实验室检查及胸部CT等资料。结果本组病例男性16例,女性13例。3例妊娠,13例合并有基础疾病。所有病例均有流感样前驱症状,呼吸道主要症状为发热、干咳少痰,严重者气短、呼吸困难、咯血。合并细菌感染时咯脓痰。肺部听诊无啰音或少啰音,合并哮喘时有哮鸣音,合并细菌感染时可有湿啰音。实验室检查65%白细胞不高或降低,41%心肌酶升高,58.6%存在低氧血症,35%呼吸衰竭。影像学表现多种多样:65.5%主要为单侧或双侧棉团样、团片样边界模糊高密度渗出影伴肺实变,其内见充气支气管征,病变沿支气管血管束分布。轻症及早期较局限,重症者及晚期病变融合呈双肺多发弥漫性改变。少数呈大叶及小叶性肺炎表现。预后大多良好,病死率6.9%。主要死亡原因为呼吸衰竭及大咯血。结论甲型H1N1流感合并肺炎是以甲型H1N1流感病毒肺炎为主要疾病的多种肺炎构成。甲型H1N1流感病毒肺炎临床表现具有流感病毒肺炎共性特点,其影像学表现有一定特征性。  相似文献   

11.
Acute leukemias (ALs) are heterogeneous diseases. Functional polymorphisms in the genes encoding detoxification enzymes cause inter-individual differences, which contribute to leukemia susceptibility. The CYP2D6, CYP1A1, CYP2E1, GSTT1, and GSTM1 polymorphisms in ALL (n = 156) and AML (n = 94) patients and 140 healthy controls were genotyped by PCR and/or PCR-RFLP using blood or bone marrow samples. No association was observed between the GSTT1 gene deletion and patients (OR = 0.8, 95% CI = 0.4-1.7 for AMLs and OR = 0.9, 95% CI = 0.5-1.6 for ALLs). Patients with ALL and AML had a higher prevalence of the GSTM1 deletions compared to controls but only the difference among adult AML patients (OR = 2.1, 95% CI = 1.0-4.2) was statistically significant. The CYP2D6*3 variant allele frequency was lower in the overall acute leukemia patients (0.6%) compared to controls (P = 0.03). CYP2D6*1/*3 genotype frequency also showed a protective association in AML patients (OR = 0.09, 95% CI = 0.01-1.7; P = 0.04). We also found a risk association for CYP2E1*5 in ALL and AML (OR = 3.6, 95% CI = 1.4-9.4 and OR = 3.9, 95% CI = 1.4-10.5, respectively). No association was found for the studied CYP2D6*4, CYP1A1*2A, and GSTT1"null" variants and the risk of acute leuke-mia (ALL or AML). This case-control study suggests a contribution of CYP2E1, CYP2D6, and GSTM1 "null" variants to the development of acute leukemias.  相似文献   

12.
We recently demonstrated that Niemann-Pick C1 (NPC1), a ubiquitous 13-pass cellular membrane protein involved in lysosomal cholesterol transport, is a critical entry receptor for filoviruses. Here we show that Niemann-Pick C1-like1 (NPC1L1), an NPC1 paralog and hepatitis C virus entry factor, lacks filovirus receptor activity. We exploited the structural similarity between NPC1 and NPC1L1 to construct and analyze a panel of chimeras in which NPC1L1 sequences were replaced with cognate sequences from NPC1. Only one chimera, NPC1L1 containing the second luminal domain (C) of NPC1 in place of its own, bound to the viral glycoprotein, GP. This engineered protein mediated authentic filovirus infection nearly as well as wild-type NPC1, and more efficiently than did a minimal NPC1 domain C-based receptor recently described by us. A reciprocal chimera, NPC1 containing NPC1L1’s domain C, was completely inactive. Remarkably, an intra-domain NPC1L1-NPC1 chimera bearing only a ~130-amino acid N–terminal region of NPC1 domain C could confer substantial viral receptor activity on NPC1L1. Taken together, these findings account for the failure of NPC1L1 to serve as a filovirus receptor, highlight the central role of the luminal domain C of NPC1 in filovirus entry, and reveal the direct involvement of N–terminal domain C sequences in NPC1’s function as a filovirus receptor.  相似文献   

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AIM To investigate the contribution of polymorphisms in the CYP1A1, CYP2E1 and EPHX1 genes on sporadic colorectal cancer(SCRC) risk. METHODS Six hundred forty-one individuals(227 patients with SCRC and 400 controls) were enrolled in the study. The variables analyzed were age, gender, tobacco and alcohol consumption, and clinical and histopathological tumor parameters. The CYP1A1 *2A, CYP1A1 *2C CYP2E1 *5B and CYP2E1 *6 polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). The EPHX1 Tyr113 His, EPHX1 His139 Arg and CYP1A1 *2C polymorphisms were detected by real-time PCR. Chisquared test and binary logistic regression were used in the statistical analysis. Haplotype analysis was conducted using the Haploview program, version 2.05.RESULTS Age over 6 2 years was a risk factor for SCRC development(OR = 7.54, 95%CI: 4.94-11.50, P 0.01). Male individuals were less susceptible to SCRC(OR = 0.55, 95%CI: 0.35-0.85, P 0.01). The CYP2E1*5B polymorphism was associated with SCRC in the codominant(heterozygous genotype: OR = 2.66, 95%CI: 1.64-4.32, P 0.01), dominant(OR = 2.82, 95%CI: 1.74-4.55, P 0.01), overdominant(OR = 2.58, 95%CI: 1.59-4.19, P 0.01), and log-additive models(OR = 2.84, 95%CI: 1.78-4.52, P 0.01). The CYP2E1*6 polymorphism was associated with an increased SCRC risk in codominant(heterozygous genotype: OR = 2.81, 95%CI: 1.84-4.28, P 0.01; homozygous polymorphic : OR = 7. 3 2, 9 5 % C I : 1.85-28.96, P 0.01), dominant(OR = 2.97, 95%CI: 1.97-4.50, P 0.01), recessive(OR = 5.26, 95%CI: 1.35-20.50, P = 0.016), overdominant(OR = 2.64, 95%CI: 1.74-4.01, P 0.01), and log-additive models(OR = 2.78, 95%CI: 1.91-4.06, P 0.01). The haplotype formed by the minor alleles of the CYP2E1*5B(C) and CYP2E1*6(A) polymorphisms was associated with SCRC(P = 0.002). However, the CYP1A1 *2A, CYP1A1 *2C, EPHX1 Tyr113 His and EPHX1 His139 Arg polymorphisms were not associated with SCRC.CONCLUSION In conclusion, the results demonstrated that CYP2E1*5B and CYP2E1*6 minor alleles play a role in the development of SCRC.  相似文献   

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目的 研究p21野生型p53活化片段1/细胞周期蛋白依赖性激酶影响蛋白1/衰老细胞衍生抑制剂1(p21WAF1/CIP1/SDI1)在大鼠肾脏中随年龄增长的表达变化规律. 方法 取3月龄、12月龄及24月龄健康雄性Wistar大鼠肾组织进行衰老相关β-半乳糖苷酶(SA-β-gal)活性染色,TUNEL法检测细胞凋亡,采用逆转录多聚酶链反应(RT-PCR)和Western印迹法(Western blot assay)分别在基因及蛋白质表达水平上检测肾脏组织中p21WAF1/CIP1/SDI1的表达变化,并用免疫组化法检测p21WAF1/CIP1/SDI1在肾脏组织中的表达与定位. 结果 大鼠肾脏组织SA-β-gal活性随年龄增长逐渐增强,凋亡细胞也随年龄增长逐渐增加(P<0.05);p21WAF1/CIP1/SDI1 mRNA表达随年龄增长逐渐增强,不同月龄比较差异有统计学意义(P<0.05).Western印迹亦显示p21WAF1/CIP1/SDI1蛋白表达随鼠龄增加逐渐增强(P<0.05).免疫组化结果显示,p21WAF1/CIP1/SDI1蛋白表达于大鼠肾小球足细胞,其在肾小管与间质细胞中也有表达,且随年龄增长表达增加(P<0.05). 结论 p21WAF1/CIP1/SDI1在大鼠肾脏组织中的表达随年龄增加而增强,可作为肾脏组织中重要的衰老指标.  相似文献   

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目的 观察8-Br-cAMP刺激下,单核细胞株THP1中ABCA1、细胞间黏附分子-1(ICAM-1)及 白介素-1β(IL-1β)mRNA和蛋白质表达的变化,阐明ABCA1基因在动脉粥样硬化(AS)形成中的可能机制.方法 复苏培养THP1单核细胞,加入8-Br-cAMP(0.5 mmol/L)刺激3、6、12、24 h,设未加刺激同时孵育24 h的细胞为阴性对照组;以荧光定量RT-PCR和Western印迹法及ELISA法检测ABCA1、ICAM-1及IL-1β mRNA和蛋白质表达量;用ABCA1的反义寡核苷酸(100 nmol/L)转染THP1细胞,给予8-Br-cAMP刺激,同样的方法观察上述指标的改变.结果 予8-Br-cAMP刺激后,THP1细胞中ABCA1、ICAM-1 mRNA和蛋白质及IL-1β蛋白质表达均增高,给予反义寡核苷酸转染后氧化低密度脂蛋白(Ox-LDL)刺激3、6 h上述指标的mRNA表达降低 (P<0.01),12、24 h蛋白质表达降低 (P<0.01).结论 THP1单核细胞中,8-Br-cAMP激活ABCA1不仅可增加细胞内胆固醇外运,还具有增加炎症因子表达的作用,在AS的发生中发挥双重作用.  相似文献   

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Please cite this paper as: Heil et al. (2010) MChip, a low density microarray, differentiates among seasonal human H1N1, North American swine H1N1, and the 2009 pandemic H1N1. Influenza and Other Respiratory Viruses 4(6), 411–416. Background  The MChip uses data from the hybridization of amplified viral RNA to 15 distinct oligonucleotides that target the influenza A matrix (M) gene segment. An artificial neural network (ANN) automates the interpretation of subtle differences in fluorescence intensity patterns from the microarray. The complete process from clinical specimen to identification including amplification of viral RNA can be completed in <8 hours for under US$10. Objectives  The work presented here represents an effort to expand and test the capabilities of the MChip to differentiate influenza A/H1N1 of various species origin. Methods  The MChip ANN was trained to recognize fluorescence image patterns of a variety of known influenza A viruses, including examples of human H1N1, human H3N2, swine H1N1, 2009 pandemic influenza A H1N1, and a wide variety of avian, equine, canine, and swine influenza viruses. Robustness of the MChip ANN was evaluated using 296 blinded isolates. Results  Training of the ANN was expanded by the addition of 71 well‐characterized influenza A isolates and yielded relatively high accuracy (little misclassification) in distinguishing unique H1N1 strains: nine human A/H1N1 (88·9% correct), 35 human A/H3N2 (97·1% correct), 31 North American swine A/H1N1 (80·6% correct), 14 2009 pandemic A/H1N1 (87·7% correct), and 23 negative samples (91·3% correct). Genetic diversity among the swine H1N1 isolates may have contributed to the lower success rate for these viruses. Conclusions  The current study demonstrates the MChip has the capability to differentiate the genetic variations among influenza viruses with appropriate ANN training. Further selective enrichment of the ANN will improve its ability to rapidly and reliably characterize influenza viruses of unknown origin.  相似文献   

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目的 研究中胚层同源盒基因1(Meox1)在急性心肌梗死大鼠心脏微血管内皮的表达情况。方法 成年雄性SD大鼠随机分成急性心肌梗死组和假手术组,采用结扎左冠状动脉前降支结扎法构建急性心肌梗死模型,假手术组仅在左冠状动脉前降支穿线不结扎,建模后将急性心肌梗死组作为实验组,假手术组作为对照组。建模后第7天处死两组大鼠,进行免疫组化染色,分析急性心肌梗死后心脏微血管上Meox1的表达情况。结果 通过免疫组化分析发现,在心肌梗死区及梗死边缘区微血管内皮可见棕黄色颗粒沉积,提示有Meox1表达;在假手术组及梗死远离区微血管内皮上未见Meox1的表达。结论 在急性心肌梗死大鼠心脏微血管内皮上Meox1表达增多,推测其可能参与心肌梗死后的血管重塑。  相似文献   

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目的研究非酒精性脂肪肝大鼠肝细胞色素P450 1A1基因和表达变化及其意义.方法雄性Wistar大鼠40只,随机分为两组,正常对照组8只,高脂饮食组2、4、8、12各8只,紫外分光光度计法检测P450 1A1活性(7-乙氧异恶唑0-脱乙基酶,EROD);免疫组织化学和Western blot方法测定肝细胞色素P450 1A1表达变化,逆转录聚合酶链反应测定肝细胞色素P450 1A1 mRNA表达变化.结果脂肪肝2、4、8和12周EROD活性分别为325.07±59.68、345.25±49.28、468.95±55.28和548.68±43.25 nmol·mg-1·min-1,与正常对照组260.42±35.32 nmol·mg-1·min-1比较明显增高(P<0.01),肝细胞色素P450 1A1基因及蛋白表达随着脂肪肝程度的加重明显增强.结论非酒精性脂肪肝大鼠肝细胞色素P450 1A1基因和表达变化与脂肪肝引起的肝脏损害程度密切相关.  相似文献   

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