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991.
The Hermansky-Pudlak syndrome (HPS) protein is part of a high molecular weight complex involved in biogenesis of early melanosomes 总被引:6,自引:0,他引:6
Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder in which oculocutaneous albinism, bleeding tendency and a ceroid-lipofuscin lysosomal storage disease result from defects of multiple cytoplasmic organelles: melanosomes, platelet dense granules and lysosomes. The HPS polypeptide, a 700 amino acid protein which is unrelated to any known proteins, is likely to be involved in the biogenesis of these different organelles. Here, we show that HPS is a non-glycosylated, non-membrane protein which is a component of two distinct high molecular weight complexes. In non-melanotic cells the HPS protein is contained almost entirely in an approximately 200 kDa complex that is widely distributed throughout the cytosol. In melanotic cells the HPS protein is partitioned between this cytosolic complex and a >500 kDa complex that appears to consist of the approximately 200 kDa complex in association with membranous components. Subcellular fractionation, immunofluorescence and immunoelectron microscopy studies indicate that the membrane-associated HPS complex of melanotic cells is associated with tubulovesicular structures, small non-coated vesicles, and nascent and early-stage melanosomes. These findings suggest that the HPS complex is involved in the biogenesis of early melanosomes. 相似文献
992.
Di Y Li J Fang J Xu Z He X Zhang F Ling J Li X Xu D Li L Li YY Huo K 《Journal of human genetics》2003,48(6):315-321
NTKL is an evolutionarily conserved kinase-like protein. The cell-cycle-dependent centrosomal localization of NTKL suggested
that it was involved in centrosome-related cellular function. The mouse NTKL protein is highly homologous with human NTKL.
A novel mouse protein was identified as an NTKL-binding protein (NTKL-BP1) by yeast two-hybrid screening, and the full-length
cDNA was amplified based on the result of a sequence data analysis cloning strategy. The full-length cDNA sequence of the NTKL-BP1 gene consists of 2,537 bp, which encode 368 amino acids. A database search revealed that homologues of NTKL-BP1 exist in
different organisms, including Arabidopsis thaliana, Drosophila melanogaster, Plasmodium falciparum, Geobacter metallireducens, Anopheles gambiae and human. It suggests that NTKL-BP1 is an evolutionarily conserved protein. The expression of NTKL-BP1 was observed in multiple normal mouse tissues. The interaction of the two proteins was confirmed by co-immunoprecipitation.
Moreover, immunofluorescent staining indicated that NTKL and NTKL-BP1 were all localized in the cytoplasm. 相似文献
993.
目的:研究血清中血管内皮生长因子(VEGF)和一氧化氮(NO)表达水平及其与大肠癌恶变程度的关系。方法:分别采用酶联免疫吸附法(ELISA)测定和分光光度法检测46例大肠癌患者术前和30例健康人血清中VEGF和NO的含量。结果:大肠癌患者血清VEGF和NO表达水平均较健康人明显增高(P<0.01),且随着大肠癌浸润深度增加、有淋巴结转移以及Dukes分期愈晚者而显著增高(P<0.01)。血清VEGF与NO含量呈明显正相关(r=0.8152,P<0.01)。结论:VEGF和NO与大肠癌的发生、发展及转移调控过程有关,术前检测血清VEGF和NO含量对判断大肠癌的浸润转移以及Dukes分期具有重要价值。 相似文献
994.
Lei C Dongqing Z Yeqing S Oaks MK Lishan C Jianzhong J Jie Q Fang D Ningli L Xinghai H Daming R 《European journal of human genetics : EJHG》2005,13(7):823-828
Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is important for downregulation of T-cell activation, and CTLA-4 gene polymorphisms have been implicated as risk factors for rheumatoid arthritis (RA). Previous studies of the association between the +49 polymorphism of the CTLA-4 gene in RA have provided conflicting results. In order to determine association of the CTLA-4 gene with RA in Chinese Han population, we used denaturing gradient gel electrophoresis (DGGE) to genotype polymorphisms of four SNPs (MH30, +49, CT60 and JO31) of the CTLA-4 gene in 326 RA patients and 250 healthy controls. Furthermore, meta-analysis of all available studies relating +49 polymorphism to the risk of RA was performed to confirm the disease association. Among the SNPs examined, the genotype frequencies of CTLA-4 +49 and CT60 in RA patients differed significantly from controls (P=0.028 and 0.007). In addition, the distribution of four haplotypes constructed by these two SNPs was significantly different between patients and controls (chi(2)=10.58, d.f. =3, P=0.014). The meta-analysis also revealed that in both European and Asian populations, the CLTA-4 +49 G allele was associated with the risk of RA. These results suggested that the CTLA-4 gene might be involved in the susceptibility to RA in the Chinese Han population and both +49 and CT60 of CTLA-4 gene might be the causal variants in RA disease. 相似文献
995.
OBJECTIVE: Propylthiouracil (PTU) could induce MPO-ANCA-positive vasculitis. The aim of this study was to compare the IgG subclass distribution and avidity of MPO-ANCA in sera from patients with primary ANCA-associated vasculitis (AASV) and PTU-induced vasculitis. METHODS: Nineteen patients with primary AASV with MPO-ANCA and thirteen patients with PTU-induced vasculitis were enrolled in the current study. Sera in both active phase and remission were collected. Anti-MPO IgG subclasses were detected by antigen specific ELISAs using specific monoclonal antibodies as second antibodies, and MPO-ANCA avidity was assessed by antigen-inhibition ELISAs. RESULTS: In primary AASV, all four anti-MPO IgG subclasses could be detected in active phase with IgG1 (100%), IgG2 (73.7%), IgG3 (63.2%) and IgG4 (94.7%), and in remission, IgG1 and IgG4 subclasses in most patients remained positive. However, in PTU-induced vasculitis, anti-MPO IgG3 subclass could not be detected, the anti-MPO IgG subclasses in active phase were IgG1 (100%), IgG2 (61.5%) and IgG4 (46.2%). Furthermore, five out of the six patients (88.8%) with PTU-induced vasculitis with positive IgG4 subclass in active phase turned to negative in remission, however, only eight out of the fourteen patients (57.1%) with primary AASV turned to negative. The median avidity constant of MPO-ANCA was 56 (8.96 to >140) x 10(7) mol/l for patients with primary AASV and 0.7 (<0.28 to >140) x 10(7) mol/l for patients with PTU-induced vasculitis respectively. Furthermore, the relative levels of MPO-ANCA avidity were associated with elevation of ESR in primary AASV and were associated with BVAS scores in patients with PTU-induced vasculitis, respectively. CONCLUSION: MPO-ANCA IgG subclass distribution and avidity were different between patients with primary AASV and PTU-induced vasculitis. It was suggested that the mechanism of ANCA production in PTU-induced vasculitis was different from that in primary AASV, and the avidity of MPO-ANCA might be associated with disease activity. 相似文献
996.
997.
取不同年龄组自发性高血压鼠的胸主动脉,颈劝脉和基底动脉,用高效液相色谱-电化学检测仪测定其去甲肾上腺素含量,并取脑软膜血管作超微结构观察,结果显示:各组高血压鼠动有脉壁去甲肾上腺素含量均下降,颈内动脉更明显;脑血管内弹性膜部分断裂,平滑肌细胞有空不包变性等。 相似文献
998.
合成肽抗原抗人免疫缺陷病毒1/2型抗体酶联试剂盒… 总被引:1,自引:0,他引:1
根据人免疫缺陷病毒的基因结构和氨基酸序列,采用因相法合成了HIV-1gp41、bp120、p24和HIV-2gp36的4条多肽,混合包被酶标板做为固相抗原,采用间接酶联免疫吸附试验,建立了检测抗-HIV-1/2IgG抗体的酶联诊断试剂盒。检测卫生部药品和生物制品检定所提供的41份质控参比血清,其特异性、敏感性均为100%,变异系数小于10%。检测186份其它病种病人血清均为阴性,与华怡、巴斯德、金 相似文献
999.
A Takemura H Okuda K Oda Y R Fang H M Hsieh Y Ohta 《Kaibogaku zasshi. Journal of anatomy》1990,65(5):374-380
An anomalous case of the right subclavian artery arising from the aortic arch as the last branch, in which the first branch was the right common carotid, the second the left common carotid and the third the left subclavian artery, was found in a 10 months human fetus among 173 fetuses. The right subclavian artery arose from the posterior wall of the aortic arch at the level of the Th4 and passed obliquely between the esophagus and the thoracic vertebrae. The right and the left vertebral arteries arising from the subclavian arteries on the same side entered the transverse foramen of the C6 of each side. This case belonged to type G of Adachi's classification and as well type 5 of Holzapfel's. The present authors wish to offer a new trial classification on these variations, including the origins and numbers of the vertebral arteries, by investigating many original reports in Japanese, as follows: 1) A new classification is fixed on the basis of the type G and H of Adachi-Williams et al.-Nakagawa in the classification of the branching types of the aortic arch. The type G represents that the right common carotid, the left common carotid, the left subclavian and the right subclavian arteries arise from the aortic arch in this order. The type H represents that the bicarotid trunk, the left subclavian and the right subclavian arteries arise from the aortic arch. 2) When the left vertebral artery arising from the aortic arch is found in the type G and H, "C" is prefixed G or H, as type CG, type CH. 3) When the right vertebral artery arising from the right common carotid artery is found, a prime mark, "', is put on G or H, as type G', type H'. 4) In order to represent a compound type of the above 2) and 3), both "C" and "' are put, as type CG', type CH'. 5) When the bilateral vertebral arteries arising from the respective subclavian artery are found in the above 2), 3) and 4) "2" postfixed "C" and the prime mark "', as type G'2, type C2G, type CG'2, type C2G', type C2G'2, type H'2, type C2H, type CH'2, type C2H', type C2H'2. According to the above new classification, Adachi's type G can be arranged into 18 branching types. This classification may be helpful and sufficient to provide more than 100 cases of the type G and H reported on Japanese.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.
用杂交瘤技术建立了6株能稳定分泌抗阴道毛滴虫单克隆抗体的细胞株,选取其中3株进行了分析。3株单抗的效价分别是:ⅣA12B1和ⅣA22B1为250000ⅡB2A1为1250000。ⅣA12B1和ⅡB2A为IgG3抗体,ⅣA2281为IgGl抗体。位点分析及免疫酶染色发现,ⅣA12B1和ⅣA22B1抗同一抗原决定簇,所针对的抗原主要分布于膜上;ⅡB2A1针对的抗原主要分布于胞浆中。3株单抗针对的抗原均为糖蛋白。特异性试验发现,这3株单抗与人白细胞、阴道上皮细胞、白色念珠菌、大肠杆菌及人毛滴虫均无交叉反应。用制备的单克隆抗体,建立了试断滴虫性阴道炎的胶乳凝集试验(LAT)。研究表明,LAT是一种敏感、特异、简单和快速的方法。 相似文献