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人乳头瘤病毒16型是导致宫颈癌发生的主要因素,其晚期蛋白L1在体内或体外可自组装形成VLP颗粒.作者构建了DNA疫苗载体pDRVI1.0-16L1,大提质粒后免疫BalB/C小鼠制备抗体,并对抗体进行了特异性鉴定,为HPV16L1预防性疫苗的进一步研究和应用奠定了基础.  相似文献   

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Protein quality-control, especially the removal of proteins with aberrant structures, has an important role in maintaining the homeostasis of non-dividing neural cells. In addition to the ubiquitin-proteasome system, emerging evidence points to the importance of autophagy--the bulk protein degradation pathway involved in starvation-induced and constitutive protein turnover--in the protein quality-control process. However, little is known about the precise roles of autophagy in neurons. Here we report that loss of Atg7 (autophagy-related 7), a gene essential for autophagy, leads to neurodegeneration. We found that mice lacking Atg7 specifically in the central nervous system showed behavioural defects, including abnormal limb-clasping reflexes and a reduction in coordinated movement, and died within 28 weeks of birth. Atg7 deficiency caused massive neuronal loss in the cerebral and cerebellar cortices. Notably, polyubiquitinated proteins accumulated in autophagy-deficient neurons as inclusion bodies, which increased in size and number with ageing. There was, however, no obvious alteration in proteasome function. Our results indicate that autophagy is essential for the survival of neural cells, and that impairment of autophagy is implicated in the pathogenesis of neurodegenerative disorders involving ubiquitin-containing inclusion bodies.  相似文献   

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恶性肿瘤可通过多种细胞机制,产生对抗癌药物和放疗的抗性,即所谓耐药现象.细胞自噬是肿瘤细胞耐药的一个重要原因.高迁移率族蛋白B-1(HMGB1)是高度保守的非组蛋白DNA结合蛋白,在DNA结构、基因转录、基因重组、DNA损伤修复以及细胞存活等方面发挥重要的调控作用;HMGB1在细胞内的功能,与其氧化还原状态和细胞定位息...  相似文献   

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目的:探讨利用白细胞介素5作为DNA疫苗佐剂增强黏膜免疫反应,提高卵透明带DNA避孕疫苗抗生育效能的可行性。方法:用pVAX1-m IL-5和卵透明带避孕疫苗pVAX1-pZP3α壳聚糖纳米微粒口服免疫雌性小鼠,共设3组,每组6只。A组单独用50μg pVAX1-pZP3α免疫;B组用疫苗加等量的pVAX1-m IL-5质粒为佐剂共免疫;C组为空白对照组。每组动物接受3次免疫(第0、3、6周)。采用ELISA法检测小鼠血清及阴道冲洗液中抗pZP3 IgA抗体。第10周雌雄交配,统计雌鼠怀孕情况;第16周取双侧卵巢作石蜡连续切片,光镜观察卵巢病理学变化。结果:B组全部小鼠血清抗体呈阳性反应,A组只有3只小鼠血清抗体呈阳性反应,且B组小鼠的抗体滴度水平均高于A组小鼠;抗生育率B组小鼠为100%,A组小鼠为50%,C组小鼠为0%,2检验分析结果表明各组间的差异有统计学意义,抗生育效能与交配时抗pZP3 IgA抗体的强度有关;卵巢切片的组织病理学观察结果表明,有抗生育效能的小鼠卵巢组织可观察到各级形态正常的卵泡,无淋巴细胞浸润,与对照组及无抗生育效能的小鼠卵巢结构无差异。结论:利用重组质粒pVAX1-m IL-5与卵...  相似文献   

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甘氨酸对内毒素诱导单个核细胞产生IL—1和TNF …   总被引:2,自引:0,他引:2  
研究甘氨酸对内毒素诱导单个核细胞产生IL-1和TNF的影响。方法用促进小鼠胸腺细胞增殖反应法测定IL-1的含量,用ELISA法测定TNF含量。结果:ET组与ET+Gly组7个样品浓度的单个细胞培养上清液中IL-1放免活性值,通过配对资料单因素方差分析差异有非常显著的统计学意义;  相似文献   

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Ambra1 regulates autophagy and development of the nervous system   总被引:1,自引:0,他引:1  
Autophagy is a self-degradative process involved both in basal turnover of cellular components and in response to nutrient starvation or organelle damage in a wide range of eukaryotes. During autophagy, portions of the cytoplasm are sequestered by double-membraned vesicles called autophagosomes, and are degraded after fusion with lysosomes for subsequent recycling. In vertebrates, this process acts as a pro-survival or pro-death mechanism in different physiological and pathological conditions, such as neurodegeneration and cancer; however, the roles of autophagy during embryonic development are still largely uncharacterized. Beclin1 (Becn1; coiled-coil, myosin-like BCL2-interacting protein) is a principal regulator in autophagosome formation, and its deficiency results in early embryonic lethality. Here we show that Ambra1 (activating molecule in Beclin1-regulated autophagy), a large, previously unknown protein bearing a WD40 domain at its amino terminus, regulates autophagy and has a crucial role in embryogenesis. We found that Ambra1 is a positive regulator of the Becn1-dependent programme of autophagy, as revealed by its overexpression and by RNA interference experiments in vitro. Notably, Ambra1 functional deficiency in mouse embryos leads to severe neural tube defects associated with autophagy impairment, accumulation of ubiquitinated proteins, unbalanced cell proliferation and excessive apoptotic cell death. In addition to identifying a new and essential element regulating the autophagy programme, our results provide in vivo evidence supporting the existence of a complex interplay between autophagy, cell growth and cell death required for neural development in mammals.  相似文献   

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p16基因在原发性肝癌中丢失的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
为了解抗癌基因P^16在原发性肝癌中的变异情况,采用判别技术研究34例原发性肝癌及其癌组织。结果显示、1例原发性肝癌存在P^16Exonl纯合子缺失,15例原发怀肝癌存在P^16Exon2纯合子缺失,其余的19例肝癌及所有的癌周组织无P^16基因纯合子失,研究结果表明P^16基因的缺失与原发性肝癌的发展发展密切相关,并提供了肝癌第9号染色体基因变的依据。  相似文献   

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Vasoregulation by the beta1 subunit of the calcium-activated potassium channel   总被引:20,自引:0,他引:20  
Small arteries exhibit tone, a partially contracted state that is an important determinant of blood pressure. In arterial smooth muscle cells, intracellular calcium paradoxically controls both contraction and relaxation. The mechanisms by which calcium can differentially regulate diverse physiological responses within a single cell remain unresolved. Calcium-dependent relaxation is mediated by local calcium release from the sarcoplasmic reticulum. These 'calcium sparks' activate calcium-dependent potassium (BK) channels comprised of alpha and beta1 subunits. Here we show that targeted deletion of the gene for the beta1 subunit leads to a decrease in the calcium sensitivity of BK channels, a reduction in functional coupling of calcium sparks to BK channel activation, and increases in arterial tone and blood pressure. The beta1 subunit of the BK channel, by tuning the channel's calcium sensitivity, is a key molecular component in translating calcium signals to the central physiological function of vasoregulation.  相似文献   

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Functional replacement of the HIV-1 rev protein by the HTLV-1 rex protein   总被引:52,自引:0,他引:52  
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目的: 分析广东地区人乳头瘤病毒(HPV)16型L1基因结构特点;构建广东分离株HPV16 L1毕赤酵母分泌型表达载体.方法:采用PCR技术从广东地区宫颈癌组织中扩增HPV16 L1基因,克隆入毕赤酵母表达载体pPICZαC,测序并对HPV16 L1基因进行序列分析.结果:成功扩增了广东地区HPV16 L1基因,并构建了其毕赤酵母表达载体pPICZαC-HPV16 L1.广东分离株HPV16 L1基因序列与德国标准株相比有16处不同,同源性为98.99%,其编码的氨基酸序列有8处发生改变;与中国标准株比较有9处不同,同源性为99.18%,其编码的氨基酸序列有4处发生变化;发现在HPV16 L1基因序列中nt5 649、nt5 652、nt5 654、nt5 657、nt5 692、nt5 693,6个位点存在突变.结论:广东地区HPV16 L1基因序列与德国标准株、中国标准株相比较均存在差异;成功构建广东地区HPV16 L1真核表达载体.  相似文献   

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介绍了基于avr-ATmega16L型MCU的污水检测系统,分析了系统的总体硬件和软件设计,特别指出了光敏传感器电路、实时日历芯片和RS-232软硬件的实现。  相似文献   

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在体外使用CD40L作用于B淋巴细胞使之活化,通过测定B淋巴细胞表面分子及分泌细胞因子的变化,探讨B淋巴细胞作为抗原递呈细胞在抗肿瘤免疫中的优势,为B淋巴细胞特异性活化细胞毒T淋巴细胞(cytotoxic T lymphocyte,CTL)进而发挥其肿瘤细胞杀伤效应奠定基础.取7名健康成人外周静脉血,经淋巴细胞分离液分离人外周血单个核细胞(PBMC),分为对照组和实验组,实验组培养液中加入加入CD40L和IL-4,共培养21 d.观察B淋巴细胞生长状况,并在第7 d、第14 d和第21 d,用流式细胞仪(FCAS)测定其表面分子CD80、CD86和CD19,在第21 d,使用酶联免疫吸附法(ELISA)测定培养液中的IL-12水平.结果显示,在CD40L的作用下,B淋巴细胞呈克隆样增殖,并高表达表面分子CD80/CD86和CD19,和对照组相比,B淋巴细胞分泌IL-12水平升高(P<0.05).上述实验结果说明通过CD40L的刺激,B淋巴细胞得到了活化,提示通过该途径活化的B淋巴细胞具备了作为抗原递呈细胞而发挥其抗肿瘤免疫治疗的能力.  相似文献   

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