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361.
pVVP3和pVHN核酸疫苗的构建、表达及对肿瘤细胞的作用 总被引:5,自引:0,他引:5
用pVAX1载体构建抗肿瘤核酸疫苗 .将鸡贫血病病毒 (CAV)的VP3基因和鸡新城疫病毒(NDV)HN基因插入载体pVAX1的多克隆位点 ,构建了 2个重组基因疫苗pVVP3和pVHN .转染OS732细胞 ,Western印迹及血凝试验检测HN基因表达状况及表达产物的活性 .RT PCR、DNALadder、TUNNEL染色检测VP3基因的表达及表达产物诱导OS732细胞凋亡作用 .酶切鉴定证实成功地构建了两个核酸疫苗 ,并能在真核细胞内表达 .含HN的核酸疫苗pVHN表达后具有血凝活性并致肿瘤细胞表面唾液酸含量降低 (P <0 0 5 ) .pVVP3的转染能导致OS732细胞凋亡 ,凋亡率可达87% .试验结果表明 ,pVVP3和pVHN两个核酸疫苗体外应用后能诱导肿瘤细胞凋亡并显著降低肿瘤细胞表面唾液酸含量 相似文献
362.
马传染性贫血病毒弱毒株感染驴胎皮肤细胞(FDD)的前病毒DNA整合动态 总被引:4,自引:0,他引:4
马传染性贫血病毒弱毒株,经驴胎皮肤细胞培养,斑点杂交及PCR检测,在感染后2-10天的细胞染色体中的检出前病毒DNA,证明EIAV弱毒株对感染细胞具有整合作用,在感染后第6天,整合的前病毒的量达到高峰,其含量与病毒的致细胞病变作用相对应。前病毒的存在形式为整合形式,未检出非整合形式的前病毒,在健康的FDD细胞中未检出的前病毒,说明EIAV属于外源性病毒。 相似文献
363.
Recruitment and positioning determine the specific role of the XPF‐ERCC1 endonuclease in interstrand crosslink repair
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Daisy Klein Douwel Wouter S Hoogenboom Rick ACM Boonen Puck Knipscheer 《The EMBO journal》2017,36(14):2034-2046
XPF‐ERCC1 is a structure‐specific endonuclease pivotal for several DNA repair pathways and, when mutated, can cause multiple diseases. Although the disease‐specific mutations are thought to affect different DNA repair pathways, the molecular basis for this is unknown. Here we examine the function of XPF‐ERCC1 in DNA interstrand crosslink (ICL) repair. We used Xenopus egg extracts to measure both ICL and nucleotide excision repair, and we identified mutations that are specifically defective in ICL repair. One of these separation‐of‐function mutations resides in the helicase‐like domain of XPF and disrupts binding to SLX4 and recruitment to the ICL. A small deletion in the same domain supports recruitment of XPF to the ICL, but inhibited the unhooking incisions most likely by disrupting a second, transient interaction with SLX4. Finally, mutation of residues in the nuclease domain did not affect localization of XPF‐ERCC1 to the ICL but did prevent incisions on the ICL substrate. Our data support a model in which the ICL repair‐specific function of XPF‐ERCC1 is dependent on recruitment, positioning and substrate recognition. 相似文献
364.
Kazuhiro Nakayama Shinichi Saito Kazuhisa Watanabe Hiroshi Miyashita Fuyuhiko Nishijima Yoshie Kamo 《Bioscience, biotechnology, and biochemistry》2017,81(6):1120-1124
The function of aryl hydrocarbon receptor repressor (AHRR) in the kidney is unclear. The present study investigated associations between AHRR Pro189Ala polymorphism and estimated glomerular filtration rates (eGFR), serum creatinine, and hemoglobin levels in 2775 Japanese adults without diabetes. In addition, we examined whether AHRR expression levels in the kidney of control and chronic kidney disease (CKD) rats were changed. Multiple linear regression analyses showed that carriers of the Ala allele had increased eGFR and lower concentrations of serum creatinine and hemoglobin (p < 0.05). Immunohistochemical analysis showed that the expression of AHRR was upregulated in the kidneys of rats with CKD. These findings suggest that AHRR plays distinct roles in kidney functions and hemoglobin values. The effects of the AHRR polymorphism might be intensified in the kidneys of patients with CKD. 相似文献
365.
范可尼贫血(Fanconi anemia, FA)是一种罕见的常染色体或X染色体连锁的隐性遗传病,其发生源于范可尼贫血基因(FA基因)突变。FA基因是一组在DNA交联损伤中起同源重组修复作用的基因。FA女性患者常见早发性卵巢功能衰退(premature ovarian insufficient, POI)的特征,而FA小鼠也表现出生殖细胞严重缺乏,这些结果提示FA基因在哺乳动物卵泡发育中起重要作用。研究显示FA基因在促进原始生殖细胞增生,维持正常卵母细胞减数分裂,参与卵泡发育的促性腺激素调节以及卵母细胞与颗粒细胞生长过程中的相互调节等方面调节卵泡发育。本文综述了FA基因在卵泡发育中的作用和分子机制方面的研究进展,为POI的病因学解析提供遗传基础。 相似文献
366.
367.
Lívia Gelain Castilhos Juliana Sorraila de Oliveira Stephen Adeniyi Adefegha Luana Pereira Magni Pedro Henrique Doleski Fatima Husein Abdalla 《Redox report : communications in free radical research》2017,22(6):451-459
Objectives: This study was conducted to assess the markers of oxidative stress, myeloperoxidase (MPO), acetylcholinesterase (AChE) and xanthine oxidase (XO) activities as well as the levels of nucleotide metabolites in sickle cell anemia (SCA) patients.Methods: Fifteen SCA treated patients and 30 health subjects (control group) were selected. The markers of oxidative stress (levels of reactive oxygen species (ROS), plasma proteins, carbonyl content, lipid peroxidation (TBARS), total thiols (T-SH), glutathione and catalase activity), MPO, AChE and XO activities as well as the levels of nucleotide metabolites were measured in SCA patients.Results: ROS, thiobarbituric acid-reactive substances (TBARS) and T-SH levels as well as the activities of catalase and MPO were significantly increased while glutathione level was reduced in SCA patients. Furthermore, a significant (P?0.001) increase in hypoxanthine level was demonstrated in SCA patients. However, the serum levels for xanthine (P?0.01) and uric acid (P?0.001) were decreased in SCA patients. A significant (P?0.001) decrease in XO activity was detected in SCA patients.Discussion: The altered parameters in SCA patients suggest that the generation and impairment of oxidative stress in this disease as well as antioxidant markers are contributory factors towards cellular redox homeostasis and alteration of purine metabolites. 相似文献
368.
马传染性贫血病毒驴白细胞弱毒疫苗gag基因的序列测定及分析 总被引:2,自引:0,他引:2
以马传染性贫血病毒(ELAV)驴白细胞弱毒疫苗株(DLA)病毒基因组RNA为材料,用RT-PCR方法扩增出EIAV gag基因,以平端针其克隆到质粒载体pUC19中,由于疫苗不是克隆株,因此通过5次单独克隆与测序,推导出EIAV-DLA gag基因的优势序列。gag基因全长1458个碱基,编码一486个氨基酸残基的前体蛋白。与美国EIAV Wyoming1369株比较,核苷酸同源性为80%,氨基酸 相似文献
369.
Fred Spoor Chris Stringer Frans Zonneveld 《American journal of physical anthropology》1998,107(1):41-50
Evidence has recently accumulated that the Singa calvaria from Sudan probably dates from Oxygen Isotope Stage 6 (>130 ka). Morphological studies have indicated a mixture of archaic and more modern human traits, but such analyses are complicated by the possibility that the vault is pathologically deformed, although the exact etiology has not been established. Now computed tomography (CT) has revealed that the right temporal bone lacks the structures of the bony labyrinth. The most likely cause of this rare pathological condition appears to be labyrinthine ossification, in which newly deposited bone obliterates the inner ear spaces following an infectious disease or occlusion of the labyrinthine blood supply. A possible cause of vascular compromise could have been the presence of an expanding acoustic neuroma in the internal acoustic meatus, which is suggested by a significantly wider right meatus compared with the left side. Interestingly, labyrinthine ossification is also consistent with the controversial diagnosis that an anemia caused the characteristic diploic widening at the parietal bosses, because prime etiological factors of ossification are among the common complications of some of these blood diseases. CT examination of the vault and a review of the literature suggest that a blood disorder may well have caused the unusual parietal morphology. Given the nature of these pathological conditions, the Singa individual must have experienced a period of considerable disability. The morphological evidence from the normal bony labyrinth on the left side and from the CT evaluation of the vault is consistent with the interpretation of Singa as a late archaic hominid or an early representative of Homo sapiens drawn from a population which might be directly ancestral to modern humans. Am J Phys Anthropol 107:41–50, 1998. © 1998 Wiley-Liss, Inc. 相似文献
370.
Israel Hershkovitz Bruce M. Rothschild Bruce Latimer Olivier Dutour Georges Lonetti Charles M. Greenwald Christine Rothschild Lyman M. Jellema 《American journal of physical anthropology》1997,104(2):213-226
The present study discusses in detail the osteological changes associated with sickle cell anemia in children and their importance in differential diagnosis. Posterior calcaneal and specific articular surface disruptive metacarpal lesions are diagnostic for sickle cell anemia. Calvarial thickening, tibial and femoral cortical bone thickening, and bowing are of more limited utility in differential diagnosis. Granular osteoporosis, pelvic demineralization and rib broadening are nonspecific. Localized calvarial “ballooning,” previously not described, may have diagnostic significance. Bone marrow hyperplastic response (porotic hyperostosis) in sickle cell anemia produces minimal radiologic changes contrasted with that observed in thalassemia and blood loss/hemolytic phenomenon. Two other issues, the osteological criteria for discriminating among the anemias and the purported relationship between porotic hyperostosis and iron deficiency anemia, are also discussed. There is sufficient information to properly diagnose the four major groups of anemias, and further, to establish that iron deficiency is only indirectly associated with porotic hyperostosis. The hyperproliferative bone marrow response (manifest as porotic hyperostosis) to blood loss or hemolysis exhausts iron stores, resulting in secondary iron deficiency. Am J Phys Anthropol 104:213–226, 1997. © 1997 Wiley-Liss, Inc. 相似文献