Isolation and Purification of Terminal Deoxynucleotidyl Transferase by Using Chromatofocusing and Preparation and Identification of Its Autiserum

Using a combined method of chromatofocus-ing and oligo(dT)-cellulose affinity chromato-graphy, the terminal deoxynucleotidyl transferase(TdT) isolated from the calf thymus was puri-     

Endothelial cell monolayer damaged by oxidized LDL:a promotion of platelet adhesion

Ｃｅｎｔｒａｌｔｏｔｈｅｐａｔｈｏｇｅｎｅｓｉｓｏｆａｔｈｅｒｏｓｃｌｅｒｏｓｉｓｉｓａｎａｂｎｏｒｍａｌｌｙｆｕｎｃｔｉｏｎｉｎｇｅｎｄｏｔｈｅｌｉｕｍａｎｄａｃｏｎｓｅｑｕｅｎｔｌｏｓｓｏｆｖａｓｃｕｌａｒｉｎｔｅｇｒｉｔｙ．Ｔｈｅｓｅａｂｎｏｒｍａｌｉｔｉｅｓｍａｙｂｅｉｎｄｕｃｅｄｂｙｈｅｍｏｄｙｎａｍｉｃｆａｃｔｏｒｓ，ｂｉｏｃｈｅｍｉｃａｌｓｕｂｓｔａｎｃｅｓ，ａｎｄａｌｓｏｂｙｏｘｉｄａｔｉｖｅｌｙｍｏｄｉｆｉｅｄｌｏｗｄｅｎｓｉｔｙｌｉｐｏｐｒｏｔｅｉｎ（ＬＤＬ）．Ｔｏｕｎｄｅｒ…     

The Isolation,Purification and Identification of Fumitremorgin B Produced by Aspergillus fumigatus

Twenty-six strains of Aspergillus fumigatus were screened for toxigenicity for fumitremorgins A and B.Twenty-three of 26 strains can produce fumitremorgin B in rice medium determined by TLC and HPLC,and no fumitremorgin A was detected.The strains of no.C4104 and no.3656 were inoculated onto 5 kg of rice media and incubated in a modified procedure.Finall,4.0g of fumitremorgin B was obtained after extraction and purification by modified methods,and was confirmed by TLC,HPLC,spectral analysis together with other physicochemical analysis.This is the first report of the preparation of fumitremorgin B in China.     

Regulation of ApoE Gene Expression in Mouse Peritoneal Macrophages by VLDL

Macrophageisoneofprecursors0far-terialwallfoamcellsandhasbeensuggest-edtoplayanimportantroleinthedevel0p-mentofather0sclerosis.Macr0phagescantakeupApoB-0rApoE-containinglip0pro-teinsviavariouslipoproteinreceptors,whichcauseslipidaccumulationinthecells.Inaddition,macr0phagescansecreteApoE['].Thoughthisphenomenonhasbeendiscoveredf6rmanyyears,itsimplicationremainsunclear.VLDLisoneof1ip0pr0teinscontainingApoE.ItcanbetakenupbymacrophagesviaApoEmediatedreceptors.SoVLDLcanstimulatelipidaccumu…     

Isolation and Characterization of Nickel Uptake by Nickel Resistant Bacterial Isolate （NiRBI）

INTRODUCTION Today indiscriminate and uncontrolled discharge of metal-contaminated industrial effluent in the environment has become an issue of major concern. Heavy metals are the major toxicants found in industrial waste water. Nickel toxicity is comparable to cobalt but its toxic effect on humans is better documented, up to 20% of the populations in industrially developed countries have positive results in epidermal testing[1]. Many industries such as electroplating, paint, pigments, b…     

Rapid activation of JNK and p38 by glucocorticoids in primary cultured hippocampal cells

Rapid activation of JNK and p38 and their translocation to the cell nucleus by glucocorticoids, corticosterone （Cort）, and bovine serum-conjugated corticosterone （Cort-BSA） were studied in primary cultured hippocampal cells by using immunoblotting and immunofluorescence confocal microscopy. The rapid activation occurred 5 min after stimulation and was maintained at plateau for as long as 2-4 hr; i. e. , the response persisted for 2 hr after washing out the 15-min application of Cort-BSA. The activation occurred at a minimal concentration of 10-9 M for Cort and 10-8 M for Cort-BSA. GDPbetaS blocked the activation, but RU38486, a nuclear glucocorticoid receptor antagonist, could not block the activation, indicating the involvement of the membrane-delineated receptor in this reaction. The protein kinase C （PKC） inhibitor Go6976 blocked the response, whereas the protein kinase A inhibitor H89 could not, implying the involvement of PKC in the intracellular signal transduction pathway. The nongenomic nature of the responses and the transduction pathway and the significance of persistent action and biological significance are discussed.     

Rapid activation of JNK and p38 by glucocorticoids in primary cultured hippocampal cells

Rapid activation of JNK and p38 and their translocation to the cell nucleus by glucocorticoids, corticosterone （Cort）, and bovine serum-conjugated corticosterone （Cort-BSA） were studied in primary cultured hippocampal cells by using immunobloting and immunofluorescence confocal microscopy. The rapid activation occurred 5 rain after stimulation and was maintained at plateau for as long as 2 4 hr; i. e. ,     

两步超速离心法快速分离大量血浆极低密度脂蛋白及低密度脂蛋白

本法先使血浆中的脂蛋白快速富集浓缩，再将脂蛋白各组份分离纯化。即具备序列漂浮法分离样品量大的长处，又具有密度梯度法离心时间短的优点。使用ＢＥＣＫＭＡＮＬ８－８０Ｍ型超速离心机，Ｔｙｐｅ７０Ｔｉ转头，分离２８０ｍｌ血浆只需超速离心５ｈ。所得极低密度脂蛋白（ＶＬＤＬ）及低密度脂蛋白（ＬＤＬ）经琼脂糖电泳、聚丙烯酰胺电泳（ＰＡＧＥ）及载脂蛋白ＳＤＳ－聚丙烯酰胺电泳（ＳＤＳ－ＰＡＧＥ）鉴定纯度良好。本文为超速离心分离制备大量血浆ＶＬＤＬ、ＬＤＬ提供了一种快速、经济的新方法。     

血浆LDL的快速提取和脂质过氧化物含量的测定

本文报道一种用柠檬酸钠缓冲液快速沉淀提取低密度脂蛋白（ＬＤＬ）的方法，获得的ＬＤＬ可达电泳纯。同时测定血浆总的脂质过氧化物（Ｔ－ＬＰＯ）和ＬＤＬ中的脂质过氧化物（ＬＤＬ－ＬＰＯ）含量。结果表明，血浆ＬＰＯ含量的变化主要发生在ＬＤＬ组分中，提示ＬＤＬ是ＬＰＯ的主要载体，ＬＤＬ－ＬＰＯ含量更能确切反映机体的脂质过氧化速率。     

Lipoprotein receptor activity of peritoneal macrophages from insulin-deficient mice

Summary Binding, uptake and degradation of¹²⁵I-labeled normal very low density lipoprotein(¹²⁵I-n-VLDL) from normal swine plasma and¹²⁵I-labeled β-migrating VLDL (¹²⁵I-β-VLDL) from hypercholesterolemic rabbit plasma by peritoneal macrophages of mice rendered insulin-deficient by streptozotocin (250 mg/kg) were studied. It was found that the amount of binding, uptake and degradation of¹²⁵I-n-VLDL by macrophages from the diabetic mice was 2-fold or 2.5-fold higher than by macrophages from normal mice, resulting from an increase in the binding capacity of VLDL receptors on the macrophages from the insulin-deficient rodents. In contrast, the binding, uptake and degradation of¹²⁵I-β-VLDL by macrophages from diabetic mice were reduced to only about 45 % of normal levels because of a decrease in the number and affinity of the receptors for β-VLDL. These experimental results indicate that n-VLDL is more important than β-VLDL in the pathogenes is of atherosclerosis in insulin-dependent diabetes.     

Statins对VLDL受体两种亚型表达的影响

目的探讨Statins类药物对极低密度脂蛋白受体（VLDLR）两种亚型表达的影响。方法在体外,用一定浓度的Statins与中低分化胃腺癌细胞株SGC7901温育不同时间,在体内用一定剂量的他汀类药物喂饲兔不同时间后,采用RT-PCR和Western免疫印迹技术检测VLDLR两种亚型mRNA和蛋白质的表达变化。结果Statins均可上调SGC7901和脂肪组织中VLDLR两型mRNA及蛋白质的表达,心肌和骨骼肌中则未发现明显的表达变化。结论Statins可能通过上调兔脂肪组织VLDLR的表达来清除血中甘油三酯。     

巨噬细胞源性载脂蛋白E在VLDL亚组份代谢中的作用

高甘油三酯（TG）血症患者血中升高的极低密度脂蛋白（VLDL）主要是贫含载脂蛋白E（ApoE）的亚组份。为研究巨噬细胞（MΦ）分泌的ApoE在其代谢VLDL中的作用，将贫含ApoE的VLDL和富含ApoE的VLDL分别与MΦ保温24h，然后测定细胞内脂质和ApoEmRNA含量。结果显示：二种亚组份所引起的MΦ内胆固醇堆积程度相当（P＞0．05）；二种亚组份也均能引起MΦ内ApoEmRNA表达增加，尤以贫含ApoE的VLDL作用显著（P＜0．05）。提示：贫含ApoE的VLDL可能促进MΦ产生更多的ApoE，进而在局部结合更多的ApoE转变为类似富含ApoE的VLDL，通过ApoE介导的受体进入MΦ，使MΦ堆积脂质。由此推测MΦ产生ApoE的功能之一是促进自身对VLDL亚组份的摄取。     

Role of VLDL receptor in the process of foam cell formation

Summary The role of very low density lipoprotein receptor (LVLDR) in the process of foam cell formation was investigated. After the primary cultured mouse peritoneal macrophages were incubated with VLDL, β-VLDL or low density lipoprotein (LDL), respectively for 24 h and 48 h, foam cells formation was identified by oil red O staining and cellular contents of triglyceride (TG) and total cholesterol (TC) were determined. The mRNA levels of LDLR, LDLR related protein (LRP) and VLDLR were detected by semi-quantitative RT-PCR. The results demonstrated that VLDL, β-VLDL and LDL could increase the contents of TG and TC in macrophages. Cells treated with VLDL or β-VLDL showed markedly increased expression of VLDLR and decreased expression of LDLR, whereas LRP was up-regulated slightly. For identifying the effect of VLDL receptor on cellular lipid accumulation, ldl-A7-VR cells, which expresses VLDLR and trace amount of LRP without functional LDLR, was used to incubate with lipoproteins for further examination. The results elucidated that the uptake of triglyceride-rich lipoprotein mediated by VLDLR plays an important role in accumulation of lipid and the formation of foam cells. QU Shen, male, born in 1954, Professor This project was supported by a grant from National Natural Sciences Foundation of China (No. 39970307).     

Role of VLDL Receptor in the Process of Foam Cell Formation

Cholesterolhasbeenshowedtoplayanimpor tantroleindevelopmentofatherosclerosis (AS) .Re centresearchesfurtherdemonstratedthat plasmatriglyceridelevelsare positivelycorrelatedwiththecoronaryarterydisease .Increasingclinicalevidenceandepidemiologicalstudiesin…     

氧化低密度脂蛋白致血管内皮损伤机制及中药复方防治的研究进展

低密度脂蛋白经氧化修饰后主要通过凝集素样氧化低密度脂蛋白受体-1导致管内皮细胞损伤,诱导黏附分子和炎症因子的合成与释放,加重血管炎症反应,诱导内皮细胞凋亡,进而导致动脉粥样硬化等心血管疾病。中药复方通过抑制低密度脂蛋白(LDL)氧化生成氧化低密度脂蛋白（OX-LDL）,防治血管内皮损伤,进而防治动脉粥样硬化的发生与发展。综述近年来有关OX-LDL损伤血管内皮细胞功能的机制,及具有抗OX-LDL损伤作用的、脑心通、冠心合剂、血脉脂康胶囊、通心络、六味地黄方,黄连解毒汤等中药复方的研究进展。     

极低密度脂蛋白受体亚型与脂蛋白的结合效应及其摄取能力的差异

目的 探讨人极低密度脂蛋白受体（VLDLR）不同亚型与配体的结合效应及其摄取能力的差异，明确其在脂蛋白代谢和泡沫细胞形成中的作用。方法 应用基因重组技术获得分别稳定表达全长VLDLR（I型）和（Mink糖链区缺失的VLDLR（Ⅱ型）的ldlA7细胞株。核素标记VLDLR的天然配体VLDL、β-VLDL以观察配体结合能力；以VLDL温育细胞，检测细胞内脂质含量，油红O染色法观察胞内脂质堆积及泡沫细胞形成情况。结果 实验发现，稳定表达Ⅰ型VLDLR的ldl—A7细胞表面结合^125I-VLDL和^125I-β—VLDL的量与胞内甘油三酯和总胆固醇的含量均明显高于表达Ⅱ型VLDLR的ldl—A7细胞，泡沫细胞形成显著。结论Ⅰ型VLDLR与VLDL、β-VLDL的结合和摄取能力明显高于Ⅱ型VLDLR，泡沫细胞形成过程中Ⅰ型VLDLR发挥着重要作用。     

高脂膳食诱发家兔血清LPO升高及LDL、VLDL和HDL在活体内的氧化修饰

为探讨高脂膳食对家兔血清过氧化脂质（ＬＰＯ）升高和ＬＤＬ、ＶＬＤＬ，特别是ＨＤＬ氧化修饰的影响。正常对照组（ｎ＝８）喂以普通饲料，高脂实验组（ｎ＝８）用高胆固醇饲料（普通饲料加５％猪油，另每只兔加喂０．５ｇ胆固醇）喂养１２周。兔血清ＬＤＬ、ＶＬＤＬ及ＨＤＬ用密度梯度超速离心法分离得到。ＬＤＬ、ＶＬＤＬ及ＨＤＬ的氧化修饰用琼脂糖凝胶电泳、２３４ｎｍ光吸收及ＴＢＡＲＳ荧光检测进行鉴定。结果显示：高脂实验组兔血清的ＴＣ、ＴＧ和ＬＰＯ均显著高于正常对照组（Ｐ＜０．０１），而ＨＤＬ－Ｃ则显著降低（Ｐ＜０．０５）；同时，高脂实验组的ＬＤＬ、ＶＬＤＬ和ＨＤＬ的电泳迁移率增加，其２３４ｎｍ光吸收及ＬＰＯ含量均显著高于正常对照组（Ｐ＜０．０１）。表明高脂膳食在诱发家兔血清ＴＣ、ＴＧ显著增高的同时，不仅可引起血浆ＬＤＬ及ＶＬＤＬ的氧化修饰，而且还可引起ＨＤＬ在活体内的氧化修饰