一个未知的特异结合雌激素效应元件编码链的单链结合蛋白

本文介绍一个不是雌激素受体（ＥＲ）却能专一地结合雌激素效应元件（ＥＲＥ）编码单链的单链结合蛋白,对此蛋白在细胞中的定位、组织中的分布、热稳定性、同二价金属离子的关系作一初步研究。发现其受雌激素负调控。此蛋白在人病理样品２９例乳癌中同ＥＲ的含量似有一定的负相关关系,讨论了上述结果的意义。     

大肠杆菌rpoH基因的克隆,表达及其产物的纯化

本文用ＰＣＲ方法获得大肠杆菌热休克蛋白转录因子σ３２的编码基因ｒｐｏＨ,并克隆在含有ｔａｃ启动子的表达载体ｐＵＨＥ中,经ＩＰＴＧ诱导,在大肠杆菌中表达了Ｃ端融合有６个寡聚组氨酸的σ３２。表达产物经金属螯合层析一步纯化,达到ＳＤＳ－ＰＡＧＥ银染一条带纯度,氨基酸组成分析及Ｎ端序列分析结果与文献报道一致。３５Ｓ细胞内参入实验表明：即使在较低的温度下,表达产物σ３２（Ｈｉｓ）６也能导致热休克蛋白如ＧｒｏＥｌ、ＤｎａＫ、Ｈｔｐ的大量合成．     

广东滩涂经济鱼类寄生吸虫──Ⅳ．独睾科─新属─新种记述（复殖目）

本文对广东滩涂经济鱼类寄生复殖吸虫独睾科ＭｏｎｏｒｃｈｉｉｄａｅＯｄｈｎｅｒ,１９１１中一新属新种;椭囊吸虫属。Ｅｌｌｉｐｔｏｂｕｒｓａｇｅｎ．ｎｏｖ．、单睾椭囊吸虫Ｅｌｌｉｐｔｏｂｕｒｓａｓｉｎｇｌｏｒｃｈｉｓｓｐ．ｎｏｖ．进行了记述。     

Distribution and Significance of Nitric Oxide Synthase in Brain Tissues of Rats Exposed to Deltamethrin Insecticide

The distribution of nitric oxide synthase(NOS)in brain tissues of rats exposed to deltamethrininsecticide has been examined by histochemical NADPH-diaphorase staining techniques on frozen sec-tions.After injection of deltamethrin(12.5mg/kg,i.p.),a reproducible sequence of toxic signs ofhyperexcitability were elicited.The observation and image analysis showed that,within brain sec-tions of rats exposed to deltamethrin,the numbers and the total staining areas of the NOS positiveneurons were greatly increased,especially in cerebral cortex,hippocampal formation and paraventric-ular nucleus.In addition,the density of single neuron and the processes were also increased.The re-sults suggested that deltamethrin may induce the NOS expression or activate the NOS activity.TheNOS activation may involve in the chains responsible for the excitatory neurotoxicities induced bydeltamethrin.     

光亲和标记鉴定玉米根脱落酸结合蛋白

光亲和标记鉴定玉米根脱落酸结合蛋白吴忠义,陈珈,朱美君（北京农业大学生物学院,１０００９４）关键词结合蛋白;光亲和标记;ＡＢＡ;受体;微粒体脱落酸（ＡＢＡ）作为一大类植物激素,在高等植物的生长发育以及对逆境的适应过程中发挥着重要作用。在探讨激素作用的...     

Tumor Necrosis Factor-α and Basic Fibroblast Growth Factor Decrease Glial Fibrillary Acidic Protein and Its Encoding mRNA in Astrocyte Cultures and Glioblastoma Cells

Abstract: Tumor necrosis factor-α is a pluripotent cytokine that is reportedly mitogenic to astrocytes. We examined expression of the astrocyte intermediate filament component glial fibrillary acidic protein in astrocyte cultures and the U373 glioblastoma cell line after treatment with tumor necrosis factor-α. Treatment with tumor necrosis factor-α for 72 h resulted in a decrease in content of glial fibrillary acidic protein and its encoding mRNA. At the same time, tumor necrosis factor-α treatment increased the expression of the cytokine interleukin-6 by astrocytes. The decrease in glial fibrillary acidic protein expression was greater when cells were subconfluent than when they were confluent. Thymidine uptake studies demonstrated that U373 cells proliferated in response to tumor necrosis factor-α, but primary neonatal astrocytes did not. However, in both U373 cells and primary astrocytes tumor necrosis factor-α induced an increase in total cellular protein content. Treatment of astrocytes and U373 cells for 72 h with the mitogenic cytokine basic fibroblast growth factor also induced a decrease in glial fibrillary acidic protein content and an increase in total protein level, demonstrating that this effect is not specific for tumor necrosis factor-α. The decrease in content of glial fibrillary acidic protein detected after tumor necrosis factor-α treatment is most likely due to dilution by other proteins that are synthesized rapidly in response to cytokine stimulation.     

Increased potency of vanadium using organic ligands

Thein vivo glucose lowering effect of orally administered inorganic vanadium compounds in diabetes was first reported in our laboratory in 1985. While both vanadate and vanadyl forms of vanadium are orally active, they are still not well absorbed. We have synthesized several organic vanadium compounds and one compound, bis(maltolato)oxovanadium(IV) or BMOV, has been extensively investigated. BMOV proved effective in lowering plasma glucose and lipids in STZ-diabetic rats when administered in drinking water over a 25 week period. The maintenance dose (0.18 mmol/kg/day) was approximately 50% of that required for vanadyl sulfate (VS). Secondary complications of diabetes were prevented by BMOV and no marked toxicity was noted. Oral gavage of STZ-diabetic rats with BMOV also reduced blood glucose levels. The ED₅₀ for BMOV was 0.5 mmol/kg, while for VS the estimated ED₅₀ was 0.9 mmol/kg. BMOV was also effective by the intraperitoneal route in STZ-diabetic rats. The ED₅₀ was 0.08 mmol/kg compared to 0.22 mmol/kg for VS. Some animals treated p.o. or i.p. remained euglycemic for up to 14 weeks. An i.v. infusion of BMOV of 0.05 mmol/kg over a 30 min period reduced plasma glucose levels by 50% while VS was not effective.     

Nonreductive release of O-linked oligosaccharides from mucin glycoproteins for structure/function assignments as neoglycolipids: application in the detection of novel ligands for E-selectin

The neoglycolipid technology comprises several microproceduresinvolving the generation of lipid-linked oligosaccharide probesfor carbohydrate recognition studies in conjunction with oligosaccharidesequence determination by mass spectrometry. Although applicableto any desired oilgosaccharides, procedures are greatly facilitatedif the ohgosaccharides are nonreduced, as conjugation is byreductive amination of a reducing end aldehyde to a phosphatidylethanolamine.Using bovine submaxillary mucin as a model for release of O-glycansin the reducing state, and based on yields of neoglycolipidsand side-products from "peeling" reactions and degradation,aqueous ethylamine 70% w/v at 22°C for 48 h has been selectedin preference to other conditions, triethylainine, sodium hydroxide,and bydrazine. The integrity of the main acidic and neutraloligosaccharides released under these conditions, di- to octasaccharides,was established by analyses of free oligosaccharides by liquidsecondary ion mass spectrometry (LSIMS) and of the derived neoglycolipidsby TLCLSIMS; the repertoire compared favorably with that ofthe oligosaccharide alditols generated by conventional reductivealkaline borohydride treatment. More forcing conditions of ethylamine70% w/v at 65°C for 6 h were required to release oligosaccharidesfrom porcine gastric mucin; di- to nonasaccharides were obtainedof which about one-third had an intact core GalNAc. Relativeto yields after reductive alkaline hydrolysis, the overall yieldsfor these two glycoproteins were 20% and 40–50% for acidicand neutral oligosaccharides, respectively. Among O-glycansreleased from an ovarian cystadenoma glycoprotein using ethylamine,three variants of the sulfated Le^a/x sequences were identifiedas ligands for the endothelial adhesion molecule E-selectin,one of which is based on the unusual backbone Gal-3/4GlcNAc-3Gal-3Gal. mucins O-linked oligosaccharides TLC-LSIMS neoglycolipids E-selectin     

枯草杆菌蛋白酶E的156和165位突变

应用定点突变方法,在M222A突变的枯草杆菌蛋白酶E基因上进行E156S和V165I定点突变. 将突变基因插入大肠杆菌-枯草杆菌穿梭质粒pBE-2中,在碱性和中性蛋白酶缺陷型的枯草杆菌DB104中进行表达,得到突变种(M222A,E156S)和(M222A,E156S,V165I)蛋白酶E. 性质测定表明,E156S突变使蛋白酶比活力增加90%,并不影响酶的热稳定性和抗氧化性. 而V165I突变使蛋白酶比活力降低.     

FK-506结合蛋白对钙释放通道的调控

细胞内自由钙作为一种重要的细胞信使广泛地参与细胞生理功能调控.胞内钙库(内质网系和肌浆网系)对调节细胞内自由钙水平起着重要的作用.钙库膜上的钙释放通道(ryanodine受体和三磷酸肌醇受体)受许多因素调控,其中之一就是新近研究得相当多的FK506结合蛋白.免疫抑制剂FK506能特异地结合钙库上一种分子质量为12 ku左右的蛋白,这种FK506结合蛋白与钙释放通道形成一种紧密连接的复合体,在正常生理情况下对钙释放通道起着十分重要的调控作用.