PI分解酶

札幌酿酒有限公司和名古屋大学药学系池泽教授共同研制出世界上第一种磷脂酶C商品制剂。此酶可分解细胞膜的主要成分磷脂酰肌醇(PI)或甘油酸磷脂。这一新产品将用作研究活体膜的试剂。公司已通过日本主要的生化试剂研制企业,Funakoshi制药公司向国内外     

PI (α1) polymorphism in the Japanese: Confirmation of PI*M4 and description of new PI variants

PI phenotyping by separator isoelectric focusing (SIEF) was performed on a total of 1000 unrelated Japanese individuals from two different areas of Western Japan. The PI M1M4 subtype was observed together with the six common PI M subtypes. PI*M4 was confirmed to be present but rare in the Japanese. Several new PI variants were identified by comparison runs of each variant with previously reported genetic variants. The significance of treatment of serum with dithiothreitol (DTT) followed by iodacetic acid (IAC) in determination of PI variants is also described.     

曹天钦学术基金会评选出本刊 2 0 0 0年优秀论文

曹天钦学术基金会最近对本刊 2 0 0 0年发表的优秀论文进行了评选。根据基金会评选细则 (见本刊 1998年第 6期 6 17页 ) ,由《生物化学与生物物理学报》编辑部根据论文的质量 (至少有一位审稿专家评为甲级 ) ,从 2 0 0 0年已发表的 137篇论文中推荐 9篇参加优秀学术论文的评选 ,然后由基金会聘请专家对所推荐论文进行了评选 ,结果公布如下 :优秀论文奖 :杨运桂 ,徐京宁 ,胡泰山 ,钱友存 ,杨胜利 ,龚　毅。信号肽疏水性的提高促进青毒素Ｇ酰化酶分泌。生物化学与生物物理学报 ,2 0 0 0 ,32 (2 ) :16 3— 16 8(专家点评 :这是一篇有关人工信号…     

中国昆虫科学 2 0 0 0年第 8卷 总目次

第 1期南极三种弹尾目昆虫记述岳巧云　田村浩志 (1)……………………………中国福建省金小蜂科三新种 (膜翅目 )肖　晖　黄大卫 (8)…………………中国姬蜂茧蜂属 (膜翅目 :茧蜂科 )记述并附一新种描述陈学新　何俊华　马　云 (13)……………………………………………………………………中国泊卡小蜂属 (膜翅目 :小蜂科 )及一新种和一新纪录种记述刘长明 (19…中国姬蜂科 (膜翅目 )二新种盛茂领　潘宏阳 (2 5)……………………………家蝇抗性和敏感品系中的乙酰胆碱酯酶动力学研究施明安　袁建忠　吴　峻　庄佩君　唐振华 (30 )………………     

δ-Opioid receptor-stimulated Akt signaling in neuroblastoma × glioma (NG108-15) hybrid cells involves receptor tyrosine kinase-mediated PI3K activation

δ-Opioid receptor (DOR) agonists possess cytoprotective properties, an effect associated with activation of the “pro-survival” kinase Akt. Here we delineate the signal transduction pathway by which opioids induce Akt activation in neuroblastoma × glioma (NG108-15) hybrid cells. Exposure of the cells to both [D-Pen^2,5]enkephalin and etorphine resulted in a time- and dose-dependent increase in Akt activity, as measured by means of an activation-specific antibody recognizing phosphoserine-473. DOR-mediated Akt signaling is blocked by the opioid antagonist naloxone and involves inhibitory G_i/o proteins, because pre-treatment with pertussis toxin, but not over-expression of the G_q/11 scavengers EBP50 and GRK2-K220R, prevented this effect. Further studies with Wortmannin and LY294002 revealed that phophoinositol-3-kinase (PI3K) plays a central role in opioid-induced Akt activation. Opioids stimulate Akt activity through transactivation of receptor tyrosine kinases (RTK), because pre-treatment of the cells with inhibitors for neurotrophin receptor tyrosine kinases (AG879) and the insulin-like growth factor receptor IGF-1 (AG1024), but not over-expression of the Gβγ scavenger phosducin, abolished this effect. Activated Akt translocates to the nuclear membrane, where it promotes GSK3 phosphorylation and prevents caspase-3 cleavage, two key events mediating inhibition of cell apoptosis and enhancement of cell survival. Taken together, these results demonstrate that in NG108-15 hybrid cells DOR agonists possess cytoprotective properties mediated by activation of the RTK/PI3K/Akt signaling pathway.     

20 0 0年阿尔伯特·拉斯克医学研究奖揭晓

阿尔伯特·拉斯克 (Albert Lasker)医学研究奖分设基础医学奖、临床医学奖和特别医学成就奖三项 .本年度该奖颁奖仪式于 9月 2 2日在美国纽约举行 ,6位科学家因对人类战胜疾病及死亡作出重要的理论贡献和其实际意义而获此殊荣 .获得基础医学奖是两位以色列科学家 Aaron Ciechanover与 Avram Hershko和加州理工学院Alexander Varshavsky.Ciechanover和 Hershko用了二十多年的时间研究蛋白质的降解机制及其对机体功能的影响 . 1 978年 ,他们发现了一种降解蛋白质的物质—— ATP依赖的蛋白质分解因子 ,即泛素 . 1 985年 ,他们证明细胞抽…     

Discovery of thiazolobenzoxepin PI3-kinase inhibitors that spare the PI3-kinase β isoform

A series of suitable five-membered heterocyclic alternatives to thiophenes within a thienobenzoxepin class of PI3-kinase (PI3K) inhibitors was discovered. Specific thiazolobenzoxepin 8-substitution was identified that increased selectivity over PI3Kβ. PI3Kβ-sparing compound 27 (PI3Kβ K_i,app/PI3Kα K_i,app = 57) demonstrated dose-dependent knockdown of pAKT, pPRAS40 and pS6RP in vivo as well as differential effects in an in vitro proliferation cell line screen compared to pan PI3K inhibitor GDC-0941. A new structure-based hypothesis for reducing inhibition of the PI3K β isoform while maintaining activity against α, δ and γ isoforms is presented.     

微生物生产辅酶Q

辅酶Q(CoQ)作为酶的辅助因子 ,可用于治疗多种疾病。有重要价值。作为医药产品 ,有针剂型和口服型。CoQ的结构与维生素K相近 ,能强化其他酶的作用效果 ,且是强力的抗氧化剂 ,有助于保护细胞不被破坏性的氧化作用所伤害。它对细胞中有“发动机”之称的线粒体及其正常功能也起关键性作用 ,如果线粒体中CoQ含量不足 ,则多种酶活力均明显下降。例如帕金森氏症患者的线粒体出现机能障碍即与CoQ1 0 水平有关。美国研究人员将CoQ1 0 用于该患者治疗 ,可使病症缓解 ,并能延缓4 4 % ,线粒体得到增强 ,也无副作用 ,有望成为帕金森氏症的治疗用药…     

Q热疫苗研究进展

本文对Q热疫苗的研究进行了回顾、总结。灭活疫苗能刺激机体产生较强的抗Q热特异性体液免疫和细胞免疫，免疫保护效果好且持续时间长。但是，灭活疫苗有较强的副反应，可引起局部脓肿等副反应。减毒疫苗虽然免疫保护效果好，但可能有毒力恢复的危险。亚单位疫苗主要有CMR、TCAE和LPS，其中CMR和TCAE具有与灭活疫苗相近的保护效果，副反应很小，已进入临床研究。目前研究较多的保护性抗原蛋白有27kD、30kD、34kD、热休克蛋白等主要表面抗原，它们有可能发展成为重组亚单位疫苗。多价亚单位疫苗、DNA疫苗以及以活菌为载体的重组菌苗将是有前途的新型Q热疫苗。     

Insulin-Driven PI3K-AKT Signaling in the Hepatocyte Is Mediated by Redundant PI3Kα and PI3Kβ Activities and Is Promoted by RAS

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PI (α1-antitrypsin) subtypes: Frequency of PI*M4 in several populations

Summary Sera from different populations (Dutch, Northern and Southern Italians and Spaniards) were screened for PI (₁-antitrypsin) types and subtypes. A polyacrylamide isoelectric focusing method was applied, which consisted of the combined use of an ultra-thin highly cross-linked gel, restricted pH range carrier ampholytes and a separator. This technique enabled easy typing and subtyping of all known PI phenotypes including PI*M subtypes. The frequency of the new PI*M4 allele was lowest of all PI*M alleles (0.0476 in The Netherlands, 0.0371 in Northern Italy, 0.0308 in Southern Italy and 0.0146 in Spain).     

PI3K 抑制剂抗肿瘤临床研究进展

磷脂酰肌醇-3-激酶 (PI3K) 是一种胞内磷脂酰肌醇激酶,在介导细胞生长、发育、分裂、分化和凋亡等过程中发挥重要作用,因此 PI3K 抑制剂的开发已成为当前抗癌新药研究的热点之一。目前已有多个 PI3K 抑制剂进入临床研究阶段或已上市,其单用或与其他药物联 用的疗效和安全性有待进一步临床验证。综述 PI3K 抑制剂作为抗肿瘤药物的临床研究进展,为其进一步研究与应用提供参考。     

长鼻浣熊有多Q

<正>我一出生就认识胡里奥叔叔了。虽然我今年刚满10岁,但,我们早已是老朋友了。我家住在危地马拉蒂卡尔城,距离玛雅寺庙遗址只有几千米的路程。每到周末,胡里奥叔叔就会开着他那辆破破烂烂的老爷卡车,来到我家的木屋前,从车窗探出脑袋冲我喊:"威尔,上车,去看长鼻浣熊啦!"     

论阿Q的形象

阿Q是鲁迅唯一的中篇小说《阿Q正传》中的典型人物。他是一个特定的时代中一群畸形的中国人的典型。作者在塑造这一形象中给他以喜剧的外套并寄寓了悲剧的内核。他的性格有许多矛盾和复杂性。