Carboxylesterase1/Esterase-x Regulates Chylomicron Production in Mice

Elevated postprandial plasma triacylglycerol (TG) concentrations are commonly associated with obesity and the risk of cardiovascular disease. Dietary fat contributes to this condition through the production of chylomicrons. Carboxylesterases have been mainly studied for their role in drug metabolism, but recently they have been shown to participate in lipid metabolism; however, their role in intestinal lipid metabolism is unknown. Carboxylesterase1/esterase-x (Ces1/Es-x) deficient mice become obese, hyperlipidemic and develop hepatic steatosis even on standard chow diet. Here, we aimed to explore the role of Ces1/Es-x in intestinal lipid metabolism. Six-month old wild-type and Ces1/Es-x deficient mice were maintained on chow diet and intestinal lipid metabolism and plasma chylomicron clearance were analyzed. Along the intestine Ces1/Es-x protein is expressed only in proximal jejunum. Ablation of Ces1/Es-x expression results in postprandial hyperlipidemia due to increased secretion of chylomicrons. The secreted chylomicrons have aberrant protein composition, which results in their reduced clearance. In conclusion, Ces1/Es-x participates in the regulation of chylomicron assembly and secretion. Ces1/Es-x might act as a lipid sensor in enterocytes regulating chylomicron secretion rate. Ces1/Es-x might represent an attractive pharmacological target for the treatment of lipid abnormalities associated with obesity, insulin resistance and fatty liver disease.     

329株深部真菌感染菌种分布及药敏试验分析

近年来临床上随着广谱抗生素、化疗药物和免疫抑制剂大量应用、艾滋病的流行以及放射治疗和器官移植的广泛进行,深部真菌病发病率大幅上升;唑类药物作为当前临床抗真菌治疗的主要药物,其使用量的增加导致临床深部真菌分离株耐药性增强、感染菌种发生变化^[1]。为了解近年来临床深部真菌感染的分布与耐药状况、分析真菌感染的流行趋势,对我院2004～2008年5年间临床深部真菌感染的病原学资料进行回顾性分析。     

高效除藻真菌云芝F21a遗传转化体系的建立

以蓝藻高效降解菌云芝F21a (Trametes versicolor)为出发菌株,对其原生质体的制备、再生条件及限制性内切酶介导的遗传转化进行研究。结果表明：在PDA培养基上,28 ℃培养4 d的菌丝最适于原生质体制备; 0.6 mol/L KCl为最适等渗条件;30 ℃混合酶液（2% cellulase+2% snailase+2% lywallzyme）酶解4 h,原生质体产量达到2.375×10⁷个/mL,此时再生率达0.74%。采用限制性内切酶介导技术可将质粒pAN7-1导入云芝F21a的原生质体,在含有150 μg/mL 潮霉素的RM培养基中能够获得再生菌株,PCR验证初步表明该质粒已经转入云芝F21a原生质体。连续传代转接显示,阳性转基因菌株外源基因可以稳定表达,本结果为研究真菌高效消除蓝藻的分子机制奠定基础。     

杭州稻麦菜轮作地区大气氮湿沉降

通过雨水中NH+4-N/NO-3-N比率和铵态氮自然丰度值(δ15NH+4)的变化探讨大气氮湿沉降与农作施肥活动的关联性. 2003年6月至2005年7月,采用自行设计定制的雨水收集器在浙江杭州稻-麦-蔬菜轮作地区进行了为期2a的全天候连续雨水采样分析.结果显示,杭州稻-麦-蔬菜轮作地区雨水中NH+4-N/NO-3-N比率和δ15NH+4值呈现相似的季节性变化,雨水中NH+4-N/NO-3-N的峰值出现在6月底～9月上旬,而后逐渐下降,秋冬季(10～11月份)降到最低;来春麦菜集中施肥期(2～3月份),又呈现多个小高峰;5～6月份为单季稻和蔬菜基肥和追肥集中施用期,故而峰值也达4以上;入冬后仅在麦田施肥期出现一个小高峰而后明显下降,大都降到1以下;频繁施肥期雨水中的NH+4-N/NO-3-N比率值是农闲期的2～4倍,显示雨水NH+4-N/NO-3-N比率与农田施肥活动有密切关联与同步性,但与气温无直接关联(R2=0.0129).雨水中δ15NH+4值的变化,与雨水中NH+4-N/NO-3-N比率相似,呈现明显的季节性变化:稻麦生育后期与种前空闲期为正值,麦稻蔬菜集中施肥期转为负值.雨水中NH+4-N/NO-3-N比率与δ15NH+4值对大气湿沉降中氮的来源、形态及地面NH3排放源的强度有一定的表征意义.     

The GG Genotype of Telomerase Reverse Transcriptase at Genetic Locus rs2736100 Is Associated with Human Atherosclerosis Risk in the Han Chinese Population

A single nucleotide polymorphism (SNP) in the second intron of human TERT (hTERT), rs2736100, acts as a critical factor in hTERT synthesis and activation. The rs2736100 SNP was found to be associated with susceptibility to many cancers. Recently, inhibition of telomerase and marked telomere shortening were determined to be closely associated with the increasing severity of atherosclerosis. The association between the SNP of rs2736100 and the presence of atherosclerosis was evaluated in 84 atherosclerosis patients and 257 healthy controls using multivariate logistic regression analyses. The proportion of the GG genotype in atherosclerosis patients (17.9%) was significantly higher than in the control group (9.7%). Eight variables, including age, gender, cholesterol, high density lipoprotein, homocysteine, total bilirubin, indirect bilirubin, and rs2736100 GG genotype, were associated with atherosclerosis with odds ratios of 1.88, 2.11, 1.66, 0.23, 1.27, 1.29, 1.53, and 1.74, respectively, using multivariate logistic regression analyses. Homozygous GG was demonstrated to be associated with the presence of atherosclerosis in our population.     

近交系小鼠H-2基因的PCR检测方法

目的建立快速、灵敏、简便的H-2基因检测方法。方法针对近交系小鼠的H-2D区和H-2K区序列,设计两对特异性引物,分别进行DNA扩增,扩增产物通过聚丙烯酰胺凝胶电泳,确定H-2基因型。结果通过PCR反应扩增小鼠H-2D区和H-2K区的基因产物,可以区分不同的近交系小鼠的H-2基因型,进而可以区分出不同品系的近交系小鼠。结论利用分子生物学方法进行近交系小鼠遗传学检测,弥补了过去各种方法的不足,并且PCR方法还具备快速、简便、成本低廉、便于普遍推广并易于和国际接轨等优点。所以通过PCR方法可以进行小鼠H-2基因型检测。     

Lettuce‐produced hepatitis C virus E1E2 heterodimer triggers immune responses in mice and antibody production after oral vaccination

The hepatitis C virus (HCV) is a major etiologic agent for severe liver diseases (e.g. cirrhosis, fibrosis and hepatocellular carcinoma). Approximately 140 million people have chronic HCV infections and about 500 000 die yearly from HCV‐related liver pathologies. To date, there is no licensed vaccine available to prevent HCV infection and production of a HCV vaccine remains a major challenge. Here, we report the successful production of the HCV E1E2 heterodimer, an important vaccine candidate, in an edible crop (lettuce, Lactuca sativa) using Agrobacterium‐mediated transient expression technology. The wild‐type dimer (E1E2) and a variant without an N‐glycosylation site in the E2 polypeptide (E1E2?N6) were expressed, and appropriate N‐glycosylation pattern and functionality of the E1E2 dimers were demonstrated. The humoral immune response induced by the HCV proteins was investigated in mice following oral administration of lettuce antigens with or without previous intramuscular prime with the mammalian HEK293T cell‐expressed HCV dimer. Immunization by oral feeding only resulted in development of weak serum levels of anti‐HCV IgM for both antigens; however, the E1E2?N6 proteins produced higher amounts of secretory IgA, suggesting improved immunogenic properties of the N‐glycosylation mutant. The mice group receiving the intramuscular injection followed by two oral boosts with the lettuce E1E2 dimer developed a systemic but also a mucosal immune response, as demonstrated by the presence of anti‐HCV secretory IgA in faeces extracts. In summary, our study demonstrates the feasibility of producing complex viral antigens in lettuce, using plant transient expression technology, with great potential for future low‐cost oral vaccine development.     

核因子 -kB 在动脉粥样硬化中的研究进展

动脉粥样硬化(atherosclerosis,AS)与心脑血管疾病及周围血管疾病等多种疾病的发病关系密切,而AS的慢性炎症性特征已被广泛认可,从早期内皮功能紊乱到最终的斑块破裂,炎性进程伴随于AS形成的各个阶段。核因子-κB(NF-κB)作为调控炎症信号的重要转录因子,通过调节细胞因子、趋化因子、粘附分子、免疫受体、氧化应激相关酶等一系列特异基因的表达而参与AS的病理过程,并在细胞凋亡和细胞增殖等方面发挥着重要的作用,是AS形成及防治相关研究中的重要靶点。本文通过概述近年来关于NF-κB通路的信号传导在AS形成中的作用,回顾本通路相关药物的研究进展,旨在探讨NF-κB在动脉粥样硬化研究中所面临的问题,为以NF-κB为靶点的抗AS药物研究提供理论参考。     

大戟内生菌的抑菌活性及其与宿主相关性研究

为了开发利用药用植物的内生菌资源,以大戟和其内生真菌作为材料,以一株乌桕来源的内生菌作为对照,研究自身具有抑菌作用的药用植物的内生菌在抑菌作用上和宿主的相关性.结果表明,大戟内生菌镰刀菌E5有抑制宿主受试病原菌的作用,并在活植物体内表现出对受试病原菌的拮抗作用;其抑菌能力受宿主成分刺激而加强,而宿主成分对受试病原菌无抑制作用,乌桕来源的内生菌链隔孢S12无抑制受试病原菌的作用.内生菌E5需要在氧气充足条件下培养才能产生抑菌作用,抑菌活性最大产生时间和生物量最大值不同时出现.内生菌E5的抑菌能力受到pH、温度、紫外线影响.大戟内生菌E以上特点,体现了其与宿主之间的互惠共生关系.     

整合素连接激酶和基质金属蛋白酶-9在非小细胞肺癌表达的研究

目的探讨整合素连接激酶(integrin-linked kinase,ILK)和基质金属蛋白酶(matrix metalloproteinase-9,MMP-9)在非小细胞肺癌(non-small cell lung cancer,NSCLC)中的表达及其与临床病理特征的关系.方法应用SP免疫组织化学方法检测74例手术切除NSCLC标本和10例正常肺组织中ILK和MMP-9蛋白的表达.结果在NSCLC组织中ILK和MMP-9蛋白的阳性表达率分别为74.5%(55/74)和71.6%(53/74),均明显高于正常肺组织(P<0.05).ILK 阳性表达率与原发灶大小,组织学类型,分化程度,淋巴结转移,临床分期均无密切关系(P>0.05);MMP-9阳性表达率与原发灶大小,组织学类型,分化程度,淋巴结转移,临床分期均有密切关系(P<0.05).结论 ILK和MMP-9蛋白过度表达可能分别在NSCLC的发生和发展过程中起重要作用.