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91.
Zhang HC Ye H Conway BR Derian CK Addo MF Kuo GH Hecker LR Croll DR Li J Westover L Xu JZ Look R Demarest KT Andrade-Gordon P Damiano BP Maryanoff BE 《Bioorganic & medicinal chemistry letters》2004,14(12):3245-3250
A novel series of acyclic 3-(7-azaindolyl)-4-(aryl/heteroaryl)maleimides was synthesized and evaluated for activity against GSK-3beta and selectivity versus PKC-betaII, as well as a broad panel of protein kinases. Compounds 14 and 17c potently inhibited GSK-3beta (IC(50)=7 and 26 nM, respectively) and exhibited excellent selectivity over PKC-betaII (325 and >385-fold, respectively). Compound 17c was also highly selective against 68 other protein kinases. In a cell-based functional assay, both 14 and 17c effectively increased glycogen synthase activity by inhibiting GSK-3beta. 相似文献
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93.
Song MS Moon HJ Kwon HI Pascua PN Lee JH Baek YH Woo KJ Choi J Lee S Yoo H Oh I Yoon Y Rho JB Sung MH Hong SP Kim CJ Choi YK 《Journal of microbiology (Seoul, Korea)》2012,50(3):478-488
The threat of a highly pathogenic avian influenza (HPAI) H5N1 virus causing the next pandemic remains a major concern. In this study, we evaluated the immunogenicity and efficacy of an inactivated whole-virus H5N1 pre-pandemic vaccine (MG1109) formulated by Green Cross Co., Ltd containing the hemagglutinin (HA) and neuraminidase (NA) genes of the clade 1 A/Vietnam/1194/04 virus in the backbone of A/Puerto Rico/8/34 (RgVietNam/04xPR8/34). Administration of the MG1109 vaccine (2-doses) in mice and ferrets elicited high HI and SN titers in a dose-dependent manner against the homologous (RgVietNam/04xPR8/34) and various heterologous H5N1 strains, (RgKor/W149/06xPR8/34, RgCambodia/04xPR8/34, RgGuangxi/05xPR8/34), including a heterosubtypic H5N2 (A/Aquatic bird/orea/W81/05) virus. However, efficient cross-reactivity was not observed against heterosubtypic H9N2 (A/Ck/Korea/H0802/08) and H1N1 (PR/8/34) viruses. Mice immunized with 1.9 μg HA/dose of MG1109 were completely protected from lethal challenge with heterologous wild-type HPAI H5N1 A/EM/Korea/W149/06 (clade 2.2) and mouse-adapted H5N2 viruses. Furthermore, ferrets administered at least 3.8 μg HA/dose efficiently suppressed virus growth in the upper respiratory tract and lungs. Vaccinated mice and ferrets also demonstrated attenuation of clinical disease signs and limited virus spread to other organs. Thus, this vaccine provided immunogenic responses in mouse and ferret models even against challenge with heterologous HPAI H5N1 and H5N2 viruses. Since the specific strain of HPAI H5N1 virus that would potentially cause the next outbreak is unknown, pre-pandemic vaccine preparation that could provide cross-protection against various H5 strains could be a useful approach in the selection of promising candidate vaccines in the future. 相似文献
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健脾化瘀中药提高胞嘧啶脱氨酶/单纯疱疹病毒胸苷激酶基因治疗肝细胞癌的实验研究 总被引:2,自引:0,他引:2
目的:观察健脾化瘀中药提高胞嘧啶脱氨酶/单纯疱疹病毒胸苷激酶基因治疗肝细胞癌的作用。方法:脂质体lipofectamine将含有双自杀基因的腺病毒载体pAd-CD/TK导人293细胞,收集病毒上清转染人肝癌细胞BEL7402,MTT法测定BEL7402细胞存活率。裸鼠人肝癌模型转染CD/TK双自杀基因后,给予5-FC500mg/kg,GCV 100mg/kg腹腔注射,同时予健脾化瘀中药960复方灌胃。观察肿瘤生长情况。结果:给予前体药物5-FC和GCV后,CD/TK转染细胞被杀死。并表现出较强的旁观者效应。转染细胞比例达到10%即表现出较强的杀伤作用(P<0.01)。健脾化瘀中药960复方具有提高旁观者效应作用,1.67ml/kg和2.5ml/kg960复方含药血清组细胞存活率显著低于对照组(P<0.01)。转染基因组应用5-FC和GCV治疗后,裸鼠肝癌的生长明显受到抑制(P<0.05),抑瘤率39.42%,单用中药组抑瘤率18.04%,中药与CD/TK 5-FC/GCV联合运用组,较单纯CD/5-FC/HSV-tk/GCV对裸鼠肿瘤模型的生长抑制作用更加明显(P<0.05),抑瘤率55.10%。结伦:腺病毒介导CD/TK自杀基因可有效地杀死人肝癌BEL7402细胞,健脾化瘀中药960复方具有显著提高CD/TK双自杀基因对人肝癌细胞的抑杀作用。 相似文献
96.
RAGE mediates amyloid-beta peptide transport across the blood-brain barrier and accumulation in brain 总被引:21,自引:0,他引:21
Deane R Du Yan S Submamaryan RK LaRue B Jovanovic S Hogg E Welch D Manness L Lin C Yu J Zhu H Ghiso J Frangione B Stern A Schmidt AM Armstrong DL Arnold B Liliensiek B Nawroth P Hofman F Kindy M Stern D Zlokovic B 《Nature medicine》2003,9(7):907-913
Amyloid-beta peptide (Abeta) interacts with the vasculature to influence Abeta levels in the brain and cerebral blood flow, providing a means of amplifying the Abeta-induced cellular stress underlying neuronal dysfunction and dementia. Systemic Abeta infusion and studies in genetically manipulated mice show that Abeta interaction with receptor for advanced glycation end products (RAGE)-bearing cells in the vessel wall results in transport of Abeta across the blood-brain barrier (BBB) and expression of proinflammatory cytokines and endothelin-1 (ET-1), the latter mediating Abeta-induced vasoconstriction. Inhibition of RAGE-ligand interaction suppresses accumulation of Abeta in brain parenchyma in a mouse transgenic model. These findings suggest that vascular RAGE is a target for inhibiting pathogenic consequences of Abeta-vascular interactions, including development of cerebral amyloidosis. 相似文献
97.
血管紧张素转换酶纯化与性质研究 总被引:5,自引:0,他引:5
为了深入了解猪肺血管紧张素转换酶 (angiotensin converting enzyme,ACE)的性质和功能 ,对猪肺 ACE的分离纯化以及部分酶学性质进行了研究 .猪肺组织匀浆经 1 .6~ 2 .6mol/L硫酸铵分级沉淀等步骤后 ,利用亲和胶进行亲和层析分离 .2 0 0 g猪肺组织中提纯出 0 .79mg ACE,比活力 38.8U/mg,SDS- PAGE电泳鉴定为一条带 ,分子量约 1 80 k D,等电点 (p I)为 p H4.5,糖含量约 2 3.6% ,氨基酸组成分析发现猪肺 ACE分子中含有 1 346个氨基酸 ,其中酸性氨基酸含量较高 ,碘乙酸的修饰结果表明猪肺 ACE中巯基基团未参与酶的催化反应 .酶反应动力学结果显示 ,ACE催化 Fa PGG底物反应时的最适 p H大约为 p H 7.6,反应活化能 Ea=4.37× 1 0 4 J/mol,酶活性部位附近的组氨酸和具有类似 α-氨基性质的氨基酸可能参与了 ACE催化反应 .有关猪肺 ACE的基本生化性质、氨基酸组成以及酶学性质的结果 ,为今后深入研究奠定了基础 . 相似文献
98.
99.
张坚宣)史庆华)潘淑娟)张锡然)单祥年)余龙)ZHANG Jian-Xuan)SHI Qing-Hua)PAN Shu-Juan)ZHANG Xi-Ran)SHAN Xiang-Nian)YU Long) 《遗传》1999,21(1):11-15
21三体是人类最常见的先天性疾病,约95%患儿的超数21号染色体来源于母亲,且随母龄增加患儿出生率也随之增加。本文首次运用胞质分裂阻滞法(CB法)对不同年龄女性体细胞进行荧光原位杂交,对其21号染色体的分离情况进行分析。结果表明,随年龄的增加,女性体细胞中21号染色体不分离也随之增加,但21号染色体丢失无年龄效应, 且21号染色体不分离频率远高于其丢失。该结果表明,女性体细胞中21号染色体不分离与生殖细胞同样存在年龄效应。
Abstract Trisomy 21 is the most common genetic desease in human. More than 90% is derived from mother. With the advancing of mother's age, the frequency of trisomy 21 is increasing. We detected the relation between chromosome 21 missegregation and age in cytokinesis-blocked female lymphocytes by in situ hybridization with chromosome 21 specfic probe. We have found that the age effect also exists in female somatic cells as in gamets. 相似文献
100.