新型甲型H1N1流感病毒神经氨酸酶抑制剂细胞水平评价体系的建立

本文旨在建立以2009新型甲型H1N1流感病毒神经氨酸酶 (neuraminidase, NA) 为靶点的神经氨酸酶抑制剂 (neuraminidase inhibitors, NAIs) 细胞水平评价体系。NA有促进流感病毒释放的作用, 本研究应用重组病毒技术, 通过将表达NA [A/California/04/2009 (H1N1)] 的质粒、表达流感病毒血凝素蛋白HA (hemagglutinin) 的质粒以及表达敲除外壳基因并带有荧光素酶报告基因的HIV-1基因组共转染至病毒生成细胞, 产生以HA、NA为外壳蛋白包裹HIV-1核心的重组病毒。在病毒释放前加入不同浓度的化合物, 收集病毒上清液感染细胞, 通过测定感染率来反映化合物对重组病毒NA的抑制作用。经用阳性对照药物奥司他韦及其羧酸盐证实本模型能够反映化合物对病毒NA的抑制作用; 在此基础上, 本研究还建立了奥司他韦耐药株评价模型。本研究所建立的体系可用于针对新型甲型H1N1流感病毒及其临床耐药株神经氨酸酶抑制剂的寻找和评价。     

一种新型流感病毒神经氨酸酶抑制剂的设计、合成及活性研究

本研究以H5N1亚型流感病毒神经氨酸酶(NA)活性位点旁的150-空穴为靶标,采用半柔性分子对接计算机模拟技术,设计并合成了一种绿原酸的结构类似物——4-(咖啡酰基)氨基丁酸,计算机模拟结果显示该化合物能够插入到N1150-空穴中并和Arg156侧链以氢键的方式结合,与N1的最佳结合自由能为-7.70 kcal.mol-1,与奥司他韦相当。同时,利用以H5N1假病毒体系为基础建立的NA抑制剂筛选模型,测定了奥司他韦、绿原酸和4-(咖啡酰基)氨基丁酸对NA的抑制作用,发现与绿原酸相比,4-(咖啡酰基)氨基丁酸显著增强了对N1型神经氨酸酶的抑制作用,但与奥司他韦仍有一定的差距。本实验初步探索了150-空穴作为新型神经氨酸酶抑制剂靶标的可能性,为开发新型神经氨酸酶抑制剂提供了新的思路。     

表达甲型H5N1禽流感病毒结构蛋白的重组痘苗病毒的构建与鉴定

目的  构建表达甲型H5N1禽流感病毒（H5N1 avian influenza A virus,H5N1 AIAV）NIBRG14株结构蛋白的重组痘苗病毒,为研制新型人用流感疫苗奠定基础。方法  通过反转录PCR扩增H5N1 AIAV NIBRG14株的血凝素（hemagglutinin,HA）和神经氨酸酶（neuraminidase,NA）编码基因,并将改造的HA、NA基因克隆至痘苗病毒穿梭质粒 pSCCK。在重组质粒与痘苗病毒天坛株（vaccinia virus Tiantan,VTT）于Vero细胞中发生同源重组后,筛选同时表达HA和NA的重组痘苗病毒（rVTT-HA/NA）,并对其进行鉴定。结果  反转录PCR扩增的HA和NA基因大小约分别为1 700和1 400 bp,与预期相同。DNA测序证实,改造的HA和NA序列正确。对获得的rVTT-HA/NA进行PCR及测序表明,HA和NA基因正确插入VTT。蛋白质印迹显示,rVTT-HA/NA感染的Vero细胞表达的HA和NA能与相应的抗体发生反应。表达的HA具有血凝活性,血凝滴度为1∶32。结论  重组痘苗病毒rVTT-HA/NA可稳定表达H5N1 AIAV NIBRG14株的HA和NA。     

多拷贝水蛭素基因在毕赤酵母中的分泌型表达

目的:通过多拷贝克隆技术实现水蛭素(Hirudin)基因在巴斯德毕赤酵母中的高效分泌表达.方法:利用基因重组技术,从pPIC9-Hirudin中扩增α-facor-Hirudin插入到载体pA0815中,并构建pA0815-(α-Hirudin)n多拷贝重组质粒,转化毕赤酵母GS115后进行诱导表达,并鉴定表达产物活性.结果:PCR证实成功构建了水蛭素多拷贝毕赤酵母表达载体pA0815-(α-Hirudin)n,经SDS-聚丙烯酰胺凝胶电泳证实能成功高效分泌重组水蛭素,活性测定表明表达的水蛭素有良好的抗凝血活性.结论:成功构建了分泌型水蛭素多拷贝质粒,筛选出多拷贝稳定整合表达菌株,成功表达出具有抗凝血活性的1 600 ATU/mL重组水蛭素,为大规模表达纯化水蛭素蛋白及其临床应用奠定了基础.     

Peramivir获准紧急用于H1N1的治疗

FDA已于近期批准BioCryst制药公司开发的神经氨酸酶抑制剂peramivir用于H1N1流感的紧急治疗,并已将其列入与H1N1流感爆发有关的突发公共卫生事件的应急措施清单,与H1N1疫苗及已批准的抗病毒药--罗氏公司的达菲(奥塞米韦)和葛兰素史克公司的Relenza(扎那米韦)共同用于H1N1的防治.     

抑制血管内皮生长因子表达的pSUPER-H1 RNA干扰系统的构建

目的构建抑制血管内皮生长因子（VEGF）活性的小干扰RNA表达载体。方法构建含有PolⅢH1启动子的pSUPER-H1质粒,化学合成3对编码短发夹RNA的寡核苷酸序列,各64个碱基,退火、克隆到经BglⅢ、HindⅢ酶切处理的pSUPER-H1质粒PolⅢH1启动子下游,获得重组pSUPER-H1-VEGF质粒,转化感受态大肠杆菌,挑选阳性克隆,抽取重组质粒,EcoRⅠ、HindⅢ双酶切电泳、测序鉴定。结果重组质粒经EcoRⅢ、HindⅢ双酶切琼脂糖凝胶电泳分析,表明64个碱基的核苷酸序列成功插入到预计位点,经测序鉴定,序列完全一致。结论重组pSUPER-H1-VEGF载体成功构建,开展了质粒介导在体内表达siRNA的方法。     

Tipα基因原核表达质粒的构建及其诱导条件的优化

目的 构建肿瘤坏死因子α诱导蛋白(Tipα)基因的原核表达载体,并优化诱导实验条件使其在大肠杆菌中表达.方法 提取幽门螺杆菌(H pylori) 26695菌株总DNA,用PCR方法扩增位于H.pylori 0596的Tipα基因编码序列.将Tipα基因与pET29a载体同时经BamH Ⅰ和XhoⅠ双酶切、纯化及连接后,构建pET29a-Tipα原核表达质粒,转化至宿主菌Top10F'中.优化实验条件使pET29a-Tipα原核质粒表达蛋白,采用SDS-PAGE和Western blot方法进行鉴定.结果 pET29a-Tipα原核表达质粒经双酶切证实插入片段分子量为519 bp DNA条带,测序结果与H.pylori 0596的Tipα基因编码序列相一致.当诱导剂异丙基-β-D-硫代吡喃半乳糖苷(IPTG)浓度为1.0 mmol/L,30℃诱导培养4h时,诱导目的蛋白表达量最高.Western blot结果证实,表达的重组蛋白可与Tipα抗体产生分子量约为21.8 KD的特异性条带.结论 成功构建了pET29a-Tipα原核表达质粒,并优化实验条件使其在大肠杆菌中表达了Tipα重组蛋白.     

甲型H1N1流感治疗新药扎那米韦

世界卫生组织(WHO)专家警示,2009年秋冬季可能出现甲型H1N1流感大规模暴发.葛兰素史克公司研发生产的神经氨酸酶抑制剂--扎那米韦吸入粉雾剂(zanamivir,依乐韦,Relenza)能有效治疗甲型和乙型流感,是WHO和美国疾病控制与预防中心(CDC)指南推荐的抗流感病毒药物,目前分离自临床的甲型H1N1流感病毒尚未见对该药耐药者.其在国内的成功上市,将进一步完善我国应对流感的防控措施.     

人感染H7N9禽流感的治疗与用药

目的探讨人感染H7N9禽流感的治疗与用药。方法采用文献检索和网络查询方法,收集H7N9禽流感最新研究动态,发病初期及轻重症患者的治疗与用药原则,重症患者的治疗措施与用药。结果 H7N9禽流感发病初期和轻症患者及早发现和治疗,重症患者采用＂四抗二平衡＂方法和人工肝技术清除体内堆积的炎症因子,合理使用神经氨酸酶抑制剂等,临床治疗效果显著。结论新型重组人感染H7N9禽流感及早发现和正确治疗,正确使用神经氨酸酶抑制剂和对症联用中药治疗效果良好。     

甲型H1N1流感重组病毒模型的建立及应用北大核心CSCD

目的:针对流感病毒感染宿主机体的作用机制,建立以甲型H1N1流感A/California/04/2009(H1N1)为靶点的重组病毒模型,并对其应用进行探索。方法:通过将表达流感病毒血凝素蛋白HA、神经氨酸酶NA及敲除外壳基因、复制基因并带有荧光素酶报告基因的HIV^(-1)质粒共转染至293T包装细胞,产生以HA[A/California/04/2009(H1N1)]和NA[A/California/04/2009(H1N1)]为膜蛋白,HIV^(-1)(p NL4-3.Luc.R-E-)为核心的重组病毒。通过该重组流感病毒模型评价阳性对照化合物(奥斯他韦、奥斯他韦酸)、中和血清以及板蓝根药材提取液对重组病毒活性的抑制作用。结果:奥司他韦、奥司他韦酸抑制重组病毒p NL+HA04+NA04的IC50为1.07×10-8 mol·L^(-1)和1.82×10-9 mol·L^(-1);中和血清的IC50为1∶320~1∶640;中药板蓝根提取液的IC50为1.91×10-5 g·m L^(-1)。结论:奥斯他韦、奥斯他韦酸、中和血清及板蓝根提取液对于重组病毒的活性有抑制作用,提示所构建的重组病毒模型可用于上述作用机制药物的筛选和评价。     

有机阴离子转运多肽1B1的遗传药理学进展

人体存在多种类型的药物转运体,对于药物的吸收、分布和排泄起重要作用。参与药物跨膜转运的转运体功能受影响,将可能导致诸多临床药物的疗效、毒副作用甚至药物相互作用的发生。在各种影响因素中,遗传多态性所起的作用最为重要,可导致基因表达和蛋白功能发生改变。目前,阐明转运体基因的多态性以及基因型与表型之间的相互关系已成为应用遗传信息指导临床个体化用药的必要步骤。本文就肝脏有机阴离子转运多肽1B1（OATP1B1[OATP-C],编码基因SLCO1B1）基因多态性对药代动力学和药效动力学的影响及其临床意义等方面的进展作一综述。     

Preferential induction of CYP1A1 and CYP1B1 in CCSP-positive cells.

Both benzo[a]pyrene (BaP) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) are potent ligands of aryl hydrocarbon receptors (AhR). Although animal studies indicate that both compounds induce pathological changes in the peripheral lung, the specific cell type involved remains unclear. Clara cells, expressing Clara cell specific protein (CCSP) and abundant in cytochrome P450, are nonciliated bronchiolar epithelial cells in the peripheral lung. Here we explore the hypothesis that CCSP-positive Clara cells are highly responsive to AhR ligands and are the primary cell type involved in BaP- and TCDD-induced toxicities. The responsiveness to AhR ligands was evaluated by measuring the respective mRNA and protein levels of cytochrome P450 1A1 (CYP1A1) and 1B1 (CYP1B1) using real-time RT-PCR and immunocytochemistry assays. Two in vitro models were used: primary cultures of human small airway epithelial (SAE) cells and rat lung slice cultures. In the presence of calcium, human SAE cells differentiated into CCSP-positive cells. BaP- and TCDD-induced mRNA and protein levels of CYP1A1 and CYP1B1 levels were significantly elevated in CCSP-positive cell cultures. Similarly, AhR mRNA and protein levels were increased in CCSP-positive cell cultures, as determined by real-time RT-PCR and Western blot analysis. When rat lung slice cultures were treated with BaP or TCDD for 24 h, CYP1A1 and CYP1B1 proteins were strongly induced in Clara cells. These results indicate that, in the peripheral lung of both rats and humans, CCSP-positive cells (Clara cells) may be more sensitive to AhR ligands than other cell types.     

Sulfation of resveratrol in human liver: Evidence of a major role for the sulfotransferases SULT1A1 and SULT1E1

Sulfation of resveratrol, a polyphenolic compound present in grapes and wine with anticancer and cardioprotective activities, was studied in human liver cytosol. In the presence of 3′-phosphoadenosine-5′-phosphosulfate, three metabolites (M1–3) whose structures were identified by mass spectrometry and NMR as trans-resveratrol-3-O-sulfate, trans-resveratrol-4′-O-sulfate, and trans-resveratrol-3-O-4′-O-disulfate, respectively. The kinetics of M1 formation in human liver cytosol exhibited an pattern of substrate inhibition with a K_i of 21.3?±?8.73?µM and a V_max/K_m of 1.63?±?0.41?µL?min^?1mg^?1 protein. Formation of M2 and M3 showed sigmoidal kinetics with about 56-fold higher V_max/K_m values for M3 than for M2 (2.23?±?0.14 and 0.04?±?0.01?µL?min^?1?mg^?1). Incubation in the presence of human recombinant sulfotransferases (SULTs) demonstrated that M1 is almost exclusively catalysed by SULT1A1 and only to a minor extent by SULT 1A2, 1A3 and 1E1, whereas M2 is selectively formed by SULT1A2. M3 is mainly catalysed by SULT1A2 and 1A3. In conclusion, the results elucidate the enzymatic pathways of resveratrol in human liver, which must be considered in humans following oral uptake of dietary resveratrol.     

Effect of TCDD exposure on CYP1A1 and CYP1B1 expression in explant cultures of human endometrium.

Endometriosis is a debilitating disease estimated to affect 10% of reproductive-age women and characterized by the growth of endometrial tissue outside of the uterus. The present study characterizes a human endometrial explant culture model for studying the direct effects of TCDD exposure by assessing the expression of CYP1A1 and CYP1B1 mRNA (Northern blotting), protein (Western blotting), and activity (7-ethoxyresorufin-O-deethylase; EROD) in explants cultured with and without TCDD. Explants were obtained at laparoscopy or laparotomy from women undergoing surgery for tubal ligation, endometriosis, or pelvic pain unrelated to endometriosis. The explants were cultured with 10 nM estradiol (E(2)) or 1 nM E(2) plus 500 nM progesterone (P(4)) with or without TCDD (first 24 h). The expression of CYP1A1 and CYP1B1 mRNA was greatest with 10 nM TCDD and increased up to 72 h after initial exposure. EROD activity increased up to 120 h. Explants from a secretory phase biopsy became reorganized in culture and formed a new epithelial membrane, while maintaining basic endometrial morphology and viability for up to 120 h. At 24 h, TCDD significantly increased CYP1A1 and CYP1B1 mRNA, and at 72 h, TCDD significantly increased EROD activity and CYP1B1 protein compared to explants cultured without TCDD for similar times. CYP1B1 protein also exhibited substantial constitutive expression that was similar in uncultured biopsies, where CYP1B1 protein was immunolocalized in the cytoplasm of epithelial glands, with only occasional patches of protein in the surface epithelial membrane. In explants cultured with and without TCDD exposure, CYP1B1 protein was localized in the cytoplasm of the new surface epithelial membrane and glands closest to the surface. CYP1A1 protein was not detected in uncultured biopsies or explants. Both younger age (age 30 and under) and proliferative phase were associated with higher TCDD-induced EROD activity in specimens treated with E(2):P(4). No significant endometriosis-related differences were observed for any of the biomarkers, but the detection of disease-specific change was limited by small sample size and variability in tissue-cycle phase. The human endometrial explant culture model will be useful for future studies of the effects of dioxin-like compounds on human endometrium in relationship to cycle phase and hormonal exposure.     

甲型H1N1流感疫苗不良事件监测及评估

目的:分析甲型H1N1流感疫苗的接种情况,及时总结接种的监测与评估,为开展甲型H1N1流感防控提供参考。方法:对国内外2009年接种甲型H1N1流感疫苗的不良反应监测报告进行分析。结果:甲型H1N1流感疫苗被认为与季节性流感疫苗总体安全性近似。结论:在甲型H1N1流感大流行的背景下,接种该疫苗利大于弊。     

Potent inhibition of human cytochrome P450 1B1 by tetramethoxystilbene

Human cytochrome P450 1B1 (CYP1B1) is found mainly in extrahepatic tissues and is overexpressed in a variety of human tumors. Metabolic activation of 17β-estradiol (E2) to 4-hydroxy E2 by CYP1B1 has been postulated to be an important factor in mammary carcinogenesis. The inhibition of recombinant human CYP1B1 by 2,2′,4,6′-tetramethoxystilbene (TMS) was investigated using either the Escherichia coli membranes of recombinant human CYP1B1 coexpressed with human NADPH-P450 reductase or using purified enzyme. 2,2′,4,6′-TMS showed potent and selective inhibition of ethoxyresorufin O-deethylation (EROD) activity of CYP1B1 with IC₅₀ values of 2 nM. 2,2′,4,6′-TMS exhibited 175-fold selectivity for CYP1B1 over CYP1A1 (IC₅₀, 350 nM) and 85-fold selectivity for CYP1B1 over CYP1A2 (IC₅₀, 170 nM). However, inhibition of human NADPH-P450 reductase activity by 2,2′,4,6′-TMS was negligible. The modes of inhibition by 2,2′,4,6′-TMS were noncompetitive for CYP1A1 and CYP1B1. Moreover, 2,2′,4,6′-TMS significantly suppressed EROD activity and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced CYP1A1 or CYP1B1 gene expression in human tumor cells such as HepG2 and MCF-10A. Taken together, our results indicate that 2,2′,4,6′-TMS is a potently selective inhibitor of human CYP1B1 as well as a suppressor of CYP1B1 expression and may be a valuable tool for determining enzyme properties of human CYP1B1.     

甲流期间469例发热病例血常规分析

目的:了解发热病人的血常规特点,做好甲流期间感染性疾病的预诊断。方法:选取我门诊2009年5月～12月期间发热分诊处接诊的病例469例,分析其体温和血常规的关系。结果:血常规分析显示,甲流期间发热患者随着体温逐渐升高,中性粒细胞百分比(NC)增高的比例显著升高,白细胞计数(WBC)和淋巴细胞百分比(LC)变化无统计学意义。结论:甲流期间,发热患者体温越高,细菌感染的趋势越大,而WBC和LC变化无特异性。     

膀胱癌患者CYP1A1基因MSPI多态性的相关分析

目的探讨细胞色素CYP1A1基因MSPI多态性与膀胱癌遗传易感性的关系。方法应用聚合酶链式反应-限制性片段长度多态性(PCR-RFLP)分析技术,检测44例膀胱癌患者(病例组)和85例同期住院非膀胱癌患者(对照组),检测CYP1A1基因MSPI多态性位点的3种基因型及等位基因的分布频率。结果在病例组CYP1A1基因MSPI位点基因型分布频率为:TT(54·5%)、TC(36·4%)、CC(9·1%),等位基因分布频率为T(72·7%)、C(27·3%);在对照组CYP1A1基因MSPI位点基因型的分布频率为TT(61·2%)、TC(31·2%)、CC(7·1%),等位基因分布频率为T(77·1%)、C(22·9%)。各个基因型在两组中所占的比例差异无统计学意义(P>0·05);T、C等位基因频率两组比较差异亦无统计学意义(P>0·05)。结论CYP1A1基因MSPI位点多态性的单独存在可能与本地区膀胱癌易感性无关。