微粒体环氧化物水解酶基因多态性与煤工尘肺易感性

目的 探讨微粒体环氧化物水解酶(EPHX1)基因单核苷酸多态性(SNPs)与煤工尘肺易感性的关系.方法 应用病例-对照的研究方法,以697例煤工尘肺患者为病例组,694例同单位、同工种、无尘肺的煤尘接触者为对照组;采用高千伏胸部x射线和体格检查确定病例和对照;采取外周静脉血,苯酚-氯仿萃取分离蛋白质,乙醇沉淀法提取DNA;根据中国人群HapMap database数据库查找SNP位点,采用ABI 7900实时PCR系统(Applied Biosystems,Foster City,CA,USA)对3个SNP位点进行基因型分型,用SDS等位基因分型软件来处理基因分型的结果.结果 3个SNP位点的基因型分布频率中,仅EPHX1 (rs2234922)病例组和对照组在共显性模型(OR=0.22,95％CI=0.06-0.79,P=0.020)、隐性模型(OR=0.23,95％CI=0.06-0.82,P=0.023)及相加模型(OR =0.75,95％CI=0.58-0.96,P=0.022)中的差异有统计学意义;对工龄和吸烟进行进一步的分层分析,发现不吸烟者携带EPHX1 (rs2234922)GG基因型发生煤工尘肺的危险性明显降低(OR=0.10,95％CI=0.01-0.83,P=0.033).结论 EPHX1 (rs2234922)位点GG基因型降低了尘肺的易感性,在尘肺的发生发展中可作为一个保护性因素.     

烟雾吸入性损伤修复中IL-1βmRNA和COX-2mRNA的表达变化及意义

目的:探讨IL-1β和COX-2在新西兰白兔烟雾吸入性损伤修复中表达的变化及其作用。方法:将新西兰白兔36只随机分为正常对照组、烟雾吸入性损伤后第1天,第4天,第7天,第14天,第21天,共6组,应用RT-PCR方法检测各组IL-1βmRNA和COX-2mRNA的表达。建立烟雾吸入性损伤修复模型,光镜下观察烟雾吸入对新西兰白兔气管、肺组织的病理变化。结果:(1)病理变化表明烟雾吸入性损伤第1、4、7天组以损伤后炎症反应为主(损伤期),第14、21天组以损伤后修复为主(修复期),这表明烟雾吸入性损伤修复模型成功建立;(2)RT-PCR结果表明:IL-1βmRNA表达在烟雾吸入性损伤后第1天立即升高,与正常对照组比较有极显著性差异(P<0.01),损伤期第1、4天组IL-1βmRNA表达明显高于修复期第14、21天组,第4天组(1.75±0.31)与第14天组(0.75±0.33)比较有极显著性差异(P<0.01);COX-2mRNA表达在烟雾吸入性损伤后第1天升高,与正常对照组比较有显著性差异(P<0.05),在第21天达到最高,修复期第14、21天组COX-2mRNA表达明显高于损伤期第1、4天组,第14天组(1.86±0.31)与第1天组(1.03±0.26)比较有极显著性差异(P<0.01)。结论:通过建立烟雾吸入性损伤修复模型,检测IL-1βmRNA与COX-2mRNA表达变化,发现IL-1βmRNA在损伤期表达上调,而COX-2mRNA在修复期表达升高,表明IL-1β和COX-2在烟雾吸入性损伤修复过程中可能具有重要作用。     

Mammalian epoxide hydrolases in xenobiotic metabolism and signalling

Epoxide hydrolases catalyse the hydrolysis of electrophilic—and therefore potentially genotoxic—epoxides to the corresponding less reactive vicinal diols, which explains the classification of epoxide hydrolases as typical detoxifying enzymes. The best example is mammalian microsomal epoxide hydrolase (mEH)—an enzyme prone to detoxification—due to a high expression level in the liver, a broad substrate selectivity, as well as inducibility by foreign compounds. The mEH is capable of inactivating a large number of structurally different, highly reactive epoxides and hence is an important part of the enzymatic defence of our organism against adverse effects of foreign compounds. Furthermore, evidence is accumulating that mammalian epoxide hydrolases play physiological roles other than detoxification, particularly through involvement in signalling processes. This certainly holds true for soluble epoxide hydrolase (sEH) whose main function seems to be the turnover of lipid derived epoxides, which are signalling lipids with diverse functions in regulatory processes, such as control of blood pressure, inflammatory processes, cell proliferation and nociception. In recent years, the sEH has attracted attention as a promising target for pharmacological inhibition to treat hypertension and possibly other diseases. Recently, new hitherto uncharacterised epoxide hydrolases could be identified in mammals by genome analysis. The expression pattern and substrate selectivity of these new epoxide hydrolases suggests their participation in signalling processes rather than a role in detoxification. Taken together, epoxide hydrolases (1) play a central role in the detoxification of genotoxic epoxides and (2) have an important function in the regulation of physiological processes by the control of signalling molecules with an epoxide structure.

Jab1基因沉默对裸鼠人喉癌移植瘤生长影响的研究

目的 探讨Jab1重组质粒对人喉鳞状细胞癌(简称鳞癌)Hep-2细胞裸鼠移植瘤生长的影响.方法 利用喉鳞癌Hep-2细胞裸鼠皮下移植瘤模型,通过向瘤体内注射pJab1、阴性对照质粒和生理盐水,观察瘤体增长情况,通过免疫组化方法、反转录聚合酶链反应( RT-PCR)观察瘤体内Jab1、p27的mRNA及蛋白表达水平的变化.结果 pJab1质粒组的肿瘤体积为(267.60±88.19)mm3((x)±s,以下同),与阴性对照组的(832.20±140.39) mm3及生理盐水组的( 895.40±145.93) mm3相比,差异有统计学意义(F=36.73,P＜0.001);免疫组化结果显示pJab1质粒组瘤内的Jab1蛋白的表达率降低为32.40％±5.59％,p27蛋白的表达率增高到76.80％±6.30％(P＜0.001),与阴性对照组及生理盐水组比较,差异有统计学意义;RT-PCR结果显示实验组瘤内Jab1的mRNA相对表达水平降低至0.65±0.03(F=558.00,P＜0.001),p27的mRNA无明显变化,为0.80±0.02(F=1.52,P＞0.05).结论 pJab1干扰质粒可明显降低裸鼠肿瘤组织内Jab1基因的表达并抑制瘤体的生长;pJab1质粒能有效抑制Jab1基因的表达,有望成为临床治疗喉癌的新途径.     

Impact of VKORC1 gene polymorphism on interindividual and interethnic warfarin dosage requirement— A systematic review and meta analysis

Introduction

Warfarin is the most widely used oral anticoagulant. It has been suggested that anticoagulation effect of warfarin is significantly associated with the polymorphism of certain genes, including Cytochrome P450 complex subunit 2C9 (CYP2C9), Vitamin K Epoxide Reductase Complex Subunit 1 (VKORC1), Gamma-Glutamyl Carboxylase (GGCX) and Apolipoprotein E (APOE) etc. The purpose of the present study was to conduct a systemic review and meta-analysis to investigate the relationship between mean daily warfarin dose (MDWD) and VKORC1 single nucleotide polymorphisms (SNPs).

Materials and Methods

Inclusion and exclusion criteria were made, and the studies between 2004 and present were searched. References were examined, and experts were consulted for additional information. Data were extracted. Revman 4.2.10 software was applied to analyze the relationship between MDWD and VKORC1 SNPs.

Results

Total 19 studies were included in the meta-analysis. The frequencies of 1173TT and − 1639 AA in Asian patients were higher than those in Caucasian and African populations. Patients with VKORC1 1173 CT and 1173 CC required 44% [95% Confidence Interval (CI); 32%, 56%] and 97% [73%, 122%] higher MDWD than 1173 TT carriers, − 1639GA and − 1639GG carriers required 52% [41%, 64%] and 102% [85%, 118%] higher MDWD than − 1639AA carriers, 3730GA and 3730AA carriers required 27% [3%, 58%] and 52% [3%, 109%] higher MDWD than 3730GG carriers. In addition, 1173C, − 1639 G and 3730 A carriers required 63% [44%, 82%], 61% [49%, 73%] and 32% [4%, 59%] higher MDWD than 1173TT, − 1639 AA and 3730GG, respectively. Sensitive analyses demonstrated that the impacts of gene polymorphism on warfarin dosage requirement were significantly different between Caucasian and Asian population, and the results of meta-analyses were stable and reliable.

Conclusion

This is the first meta-analysis about the impact of VKORC1 gene polymorphism on warfarin dose requirement. Our studies showed that gene polymorphisms of VKORC1 significantly associated with the variation of interindividual warfarin dose requirement variation, and the effects are different in ethnicities.     

正常和OVX大鼠体外骨髓破骨细胞样细胞培养方法的建立

目的 建立正常和ＯＶＸ大鼠体外髓破骨细胞样细胞（ＯＣＬ）培养方法。方法 取不同时间大鼠骨髓，用αＭＥＭ和１，２５（ＯＨ）２Ｄ３在２４孔培养板上培养７天后观察ＯＬＣ形成。结果 体外ＯＬＣ细胞ＴＲＡＣＰ阳性，电镜下骨片有骨吸收现象。不同时间ＯＶＸ大鼠ＯＬＣ数明显高于正常大鼠（Ｐ〈０．０５）。结论 ＯＶＸ大鼠因雌激素明显降低，破骨细胞形成增多，骨吸收增加，导致骨质疏松发生。     

羧基酯酶多态和有机磷农药接触者的易感性

目的　研究参与有机磷农药代谢的羧基酯酶的多态与有机磷接触者易感性的关系。方法　用聚合酶链反应-限制性片段长度多态性法(PCR RFLP)确定75例长期接触有机磷农药工人的丁酰胆碱酯酶(BChE)和对氧磷酶(PonE)的基因型,以症状积分和乙酰胆碱酯酶(AChE)活力(mmol·h-1·ml-1)作为反映其健康状况的指标。分析单基因位点多态工人的健康状况,确定其易感基因型,进行多基因综合分析,考虑年龄、性别以及接触时间的影响,建立多元线性回归方程。结果　BChE基因K位点(BChE K)正常纯合子(6 1例)、杂合子(12例)和异常纯合子(2例)的AChE活力为10 5 .0±2 3.0、84 .4±16 .4和79.0±9.9,症状积分为3.7±3.8、9.2±3.0和12 .5±0 .7;PonE 192位(PON 192 )正常纯合子(37例)、杂合子(2 7例)和异常纯合子(11例)的AChE活力为116 .8±15 .1、91.2±15 .6和72 .3±2 1.4 ,症状积分为2 .0±3.2、6 .7±3.3和9.7±1.8;PonE 5 5位(PON 5 5 )正常纯合子(70例)、杂合子(5例)的AChE活力为10 2 .4±2 3.0、82 .8±2 2 .0 ,症状积分为4 .5±4 .2、9.2±3.6。3个位点的杂合子和(或)异常纯合子与正常纯合子的症状积分差异都有统计学意义(P <0 .0 5 ) ;异常纯合子的症状积分最高、健康状况最差。3个基因位点没有交互作用;单个基因位点对症     

Chemopreventive effects of 2-(Allylthio)pyrazine

A series of organosulfur compounds were synthesized with the aim of developing chemopreventive compounds active against hepatotoxicity and chemical carcinogenesis. 2-(Allylthio) pyrazine (2-AP) was effective in inhibiting cytochrome P450 2E1-mediated catalytic activities and protein expression, and in inducing microsomal expoxide hydrolase and major glutathione S-transferases. 2-AP reduced the hepatotoxicity caused by toxicants and elevated cellular GSH content. Development of skin tumors, pulmonary adenoma and aberrant crypt foci in colon by various chemical carcinogens was inhibited by 2-AP pretreatment. Anticarcinogenic effects of 2-AP at the stage of initiation of tumors were also observed in the aflatoxin B₁ (AFB₁)-induced three-step medium-term hepatocarcinogenesis model. Reduction of AFB₁-DNA adduct by 2-AP appeared to result from the decreased formation of AFB₁-8,9-epoxide via suppression of cytochrome P450, while induction of GST by 2-AP increases the excretion of glutathione-conjugated AFB₁. 2-AP was a radioprotective agent effective against the lethal dose of total body irradiation and reduced radiation-induced injury in association with the elevation of detoxifying gene expression. 2-AP produces reactive oxygen speciesin vivo, which is not mediated with the thiol-dependent production of oxidants and that NF-κB activation is not involved in the induction of the detoxifying enzymes. The mechanism of chemoprotection by 2-AP may involve inhibition of the P450-mediated metabolic activation of chemical carcinogens and enhancement of electrophilic detoxification through induction of phase II detoxification enzymes which would facilitate the clearance of activated metabolites through conjugation reaction.     

Inhibition of Angiogenesis by Rhizoxin, a Microbial Metabolite Containing Two Epoxide Groups

Previous studies by our and other groups have shown that microbial products containing more than one epoxide group, including eponemycin, radicicol, depudecin and AGM-1470, exhibit anti-angio-genic activity in an in vivo assay system involving chorioallantoic membranes (CAMs) of growing chick embryos. Based on these findings, rhizoxin, a microbial metabolite that contains two epoxide groups and exhibits anti-tubulin activity, was tested for anti-angiogenic activity in a CAM assay system. Rhizoxin caused dose-dependent inhibition of embryonic angiogenesis, the ID_S(1 value being 2 ng (3.2 pmol) per egg. In addition, this compound (2 nig/kg i.p.) significantly suppressed neovascnlarizatlou induced by M5076 mouse tumor cells in a mouse dorsal air sac assay system, compared to the vehicle alone (P<0.05). These results indicate that rhizoxin is a novel inhibitor of angiogenesis, and that it has potential as a new therapeutic agent for cancer.