维生素E琥珀酸酯诱导人胃腺癌细胞凋亡途径

目的　探讨维生素E琥珀酸酯 (VES)诱导人胃腺癌SGC -790 1细胞凋亡的死亡受体 (Fas)信号转导途径。方法　人胃腺癌SGC -790 1细胞经不同剂量VES(5,10 ,2 0 μg/ml)处理 ,同时做琥珀酸、维生素E和空白对照 ,采用DAPI(4,6-贰脒基 -2 -苯基吲哚 )荧光染色法观察细胞凋亡情况 ,用WesternBlot法检测Fas、带有死亡结构域的Fas相关蛋白 (FADD)和天冬氨酸特异性半胱氨酸蛋白酶 (caspase -8)蛋白表达情况 ,Fas和FADD反义寡聚核苷分别转染SGC -790 1细胞后 ,用荧光法检测caspase -8活性。 结果　经VES处理后的细胞DAPI染色可见凋亡的形态学改变 ,2 0 μg/mlVES处理 48h后的细胞凋亡率为 89.6% ;VES处理 48h后Fas、FADD和caspase -8蛋白表达明显增加 ,且呈剂量 -效应关系 ;阻断Fas可明显抑制FADD蛋白表达 ,Fas和FADD反义寡聚核苷转染细胞后caspase -8活性明显降低 (P <0 .0 1) ,其中阻断Fas的效果高于阻断FADD。结论　维生素E琥珀酸酯诱导人胃腺癌SGC -790 1细胞凋亡过程中启动了Fas信号转导途径 ,VES启动Fas后 ,FADD将Fas和caspase -8联接起来 ,活化caspases级联反应 ,从而构成Fas/FADD/caspase -8的凋亡信号途径     

老年轻度认知功能损害患者血清维生素E、超氧化物歧化酶和丙二醛的测定及临床意义

目的　了解轻度认知功能损害 (MCI)患者血清维生素E(VitE)、超氧化物歧化酶 (SOD)和丙二醛(MDA)的水平 ,探讨其变化的临床意义。方法　采用 1∶1配对病例对照设计 ,受试者均于晨 7时空腹抽静脉血 ,应用紫外分光光度法测定了 4 5例老年MCI患者和 4 5例健康老年人血清VitE ,SOD和MDA的含量。结果　老年MCI患者血清VitE含量及SOD活性显著低于健康老年人 (P <0 .0 1) ,血清MDA含量显著高于健康老年人 (P <0 .0 1)。结论　以MDA为代表的自由基代谢产物参与了MCI的病理生理过程 ;临床上应给予外源性VitE以进行早期干预治疗。     

O-GlcNAc糖基转移酶在原核和真核细胞中的表达和提纯

目的 :本文为进一步研究蛋白 O- Glc NAc糖基化修饰提供重要资源。方法 :为了探索制备纯化具有生物学活性的重组 OGT的有效方法 ,本文用大肠杆菌和 Hi5昆虫细胞表达并纯化具有活性的重组 OGT。携带人 OGTc DNA的 PET32 a质粒在大肠杆菌中表达出带有 1个 S- Tag的重组人 OGT融合蛋白 ,然后用与 S-蛋白质偶联的琼脂糖凝胶颗粒从细菌裂解液中亲和纯化 OGT融合蛋白。结果 :其纯化的 OGT在电泳中显现单一条带并具有生物活性 ,但其活性在洗脱后丧失。在 Hi5昆虫细胞中表达的鼠肝 OGT带有一 His6 tag,经镍离子螯合柱纯化后 ,其比活性达到 0 .88nmol· min- 1 · mg- 1 OGT。结论 :在这两个表达系统中制备重组 OGT各有利弊。     

高脂血清对人内皮细胞前列环素、脂质过氧化物的影响及维生素E的保护作用

实验比较了高脂兔血清（ＨＲＳ）和正常兔血清（ＮＲＳ）对培养的人脐静脉内皮细胞（ＥＣ）脂质过氧化物（ＬＰＯ）的形成和ＥＣ利用外源性花生四烯酸（ＡＡ）合成前列环素（ＰＧＩ２）能力的影响；同时观察了抗氧化剂ＶｉｔＥ对ＥＣ的保护作用。结果表明，ＨＲＳ对ＥＣ合成ＰＧＩ２的影响有一时间和浓度相关的反应过程。用ＨＲＳ孵育培养呈融合状的ＥＣ，在４８ｈ前刺激ＰＧＩ２的产生，４８ｈ达最高值，然后急骤下降；而ＬＰＯ含量随着孵育时间的延长呈直线上升（ｒ＝０．９８７）。随着ＨＲＳ浓度的增加，ＬＰＯ含量逐渐升高，ＥＣ合成ＰＧＩ２能力呈下降趋势。ＶｉｔＥ可阻止ＨＲＳ引起的ＥＣ中ＬＰＯ含量的增加和ＰＧＩ２合成能力的下降。     

Inhibitory Effect of Cryptoporic Acid E, a Product from Fungus Cryptoporus volvatus, on Colon Carcinogenesis Induced with N-Methyl-N-Nitrosourea in Rats and with 1,2-Dimethylhydrazine in Mice

The antitumorigenic effect of cryptoporic acid E (CPA-E), a dimeric drimane sesquiterpenoid isolated from the fungus Cryptoporus volvatus , on colon carcinogenesis was investigated. Female F344 rats given an intrarectal instillation of 2 mg of N-methyl-N-nitrosourea 3 times weekly in weeks 1 and 2 were fed diet containing 0.2% CPA-E from week 3. Femal ICR mice given 15 weekly intraperitoneal injections of 10 mg of 1,2-dimethylhydrazine/kg body weight during weeks 1 to 15 were fed diet containing 0.06% CPA-E from week 1. The experiment was terminated at week 35 for rats and at week 25 for mice. The incidence and the number of tumors per animal were reduced in CPA-E-fed animals compared to the controls: 31% vs. 75% (P<0.05) and 0.4±0.2 (SEM) vs. 0.9 ± 0.2 (0.1> P >0.05) in rats, and 31% vs. 63% (0.1>P>0.05) and 0.4±0.2 vs. 2.4 ± 0.8 (P<0.05) in mice (16 animals in each group). Intrarectal deoxycholic acid-induced colonic mucosal ornithine decarboxylase activity was significantly lowered in CPA-E-fed animals compared to controls. This shows an antipromoting activity of CPA-E against colon carcinogenesis. Thus, it was concluded that CPA-E inhibits colon cancer development in both rats and mice treated with 2 different colon carcinogens.     

E1 Tor Vibio Cholerae Strain SM_6 and Jiangsu 1d Strain

Ｅ１ＴｏｒＶｉｂｉｏＣｈｏｌｅｒａｅＳｔｒａｉｎＳＭ_６ａｎｄＪｉａｎｇｓｕ１ｄＳｔｒａｉｎ￥ＪｉａｎｇＸｉａｏｗａｎ，ｅｔａｌ．ＡＣＴＡＡＣＡＤＥＭＩＡＥＭＥＤＩＣＩＮＡＥＮＡＮＪＩＮＧ，１９９４，１４（２）：１６３－１６４ＡｂｓｔｒａｃｔＥ１Ｔｏ?..     

Natural history of atopic dermatitis and its relationship to serum total immunoglobulin E in a population-based birth cohort study

We investigated the natural history of atopic dermatitis (AD) in a population-based birth cohort and assessed whether children at risk of visible eczema at 5 years of age can be identified from total immunoglobulin E (IgE) levels measured at 8, 12 and 18 months. AD data collected included a whole body examination for visible eczema at 49 months (4 years) and 61 months (5 years) of age and parent completed questionnaire data throughout their early lives. Children were divided into four groups based on their natural history of early AD: persistent (AD at 1, 6, 18, 30 and 42 months, n  = 34), intermittent early onset (before 18  months of age, n  = 495), intermittent late onset (18–42 months of age, n  = 273) and unaffected ( n  = 429). Visible eczema at 5 years of age was present in 12.2% (117/957) (95% confidence interval [CI] 10.1–14.3%) of the children. Levels of total IgE at 8, 12 and 18 months of age were associated with early onset of AD, but not with AD of later onset. For all four natural history groups, the geometric mean total IgE at 12 months was higher in those who subsequently had visible eczema than those who did not. However, the degree of overlap was such that total IgE at 12 months of age was a poor predictor of eczema at age five. A cutoff point of 78 kU/l had the highest positive predictive value for visible eczema at 5 years of age of 28.6%, with a sensitivity of 12% and specificity of 95%.     

eIF4E在乳腺癌中表达的研究进展

真核细胞翻译起始因子是调节蛋白质翻译的关键因素,作为mRNA帽结合磷蛋白,过度表达能使一些肿瘤相关恶性基因的蛋白质表达量发生变化,引起致癌性改变。笔者就eIF4E在乳腺癌中的表达、作用以及治疗研究的最新研究进展作一综述。     

前列腺素E1抑制血吸虫病家兔肝脏Ⅰ，Ⅲ型胶原生成的研究

目的:探讨前列腺素E1对血吸虫病家兔肝脏Ⅰ，Ⅲ型胶原的生成及分子伴侣Grp78/BiP基因表达的影响。 方法:用血吸虫尾蚴皮肤敷贴法感染14只家兔，构建血吸虫病肝纤维化动物模型。其中7只兔于感染后60d开始静脉注射PGE1［2.5μg/（kg.d）］至120d。用RT-PCR检测肝组织Ⅰ，Ⅲ型胶原和Grp78/BiP基因mRNA的表达水平。 结果:血吸虫病家兔肝纤维化形成过程中Ⅰ，Ⅲ型胶原基因表达水平明显增加，分别为(14.81±3.57)%和(12.9±3.25) %;Grp78/BiP mRNA表达显著上调(P<0.05)。外源性PGE1与模型组比较显著降低胶原Ⅰ，ⅢmRNA，分别为(5.79±1.26)%和(5.34±1.08) % （P<0.01)。分子伴侣Grp78/BiP mRNA水平显著下调，分别为(0.43±0.07)%和(0.29±0.02) % （P<0.05)。结论:PGE1可通过抑制基因表达和阻遏胶原成熟而有效地降低血吸虫病家兔肝脏胶原纤维的生成。