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miR-10b介导NKG2D调节脑胶质瘤细胞免疫效应的实验研究
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作者 袁岗 巨虎 +3 位作者 肖宗宇 李文辉 曹立新 惠超杰 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第3期507-512,共6页
目的:观察微小核糖核酸-10b(miR-10b)对脑胶质瘤细胞免疫效应的调节作用并探讨其作用机制。方法:取人脑胶质瘤细胞U251进行培养和传代,获得处于对数生长期的细胞。按照1.0×105个/ml浓度制备细胞悬液,并设置对照组、过表达组、低表... 目的:观察微小核糖核酸-10b(miR-10b)对脑胶质瘤细胞免疫效应的调节作用并探讨其作用机制。方法:取人脑胶质瘤细胞U251进行培养和传代,获得处于对数生长期的细胞。按照1.0×105个/ml浓度制备细胞悬液,并设置对照组、过表达组、低表达组、空白组,每组6个复孔。对照组、过表达组、低表达组分别采用脂质体转染法转染阴性对照、miR-10b模拟物、miR-10b抑制剂,空白组予以等量无菌生理盐水。分离和培养1例健康志愿者外周血自然杀伤(NK)细胞。MTT法检测不同效靶比时NK细胞的杀伤活性;流式细胞仪检测各组NK细胞表面NK细胞激活受体(NKG2D)表达,并检测各组人脑胶质瘤细胞U251表面主要组织相容性复合物Ⅰ链相关基因A(MICA)、UL16结合蛋白2(ULBP2)、UL16结合蛋白3(ULBP3)表达。结果:对照组、过表达组、低表达组转染效率分别为(93.55±2.05)%、(95.67±3.14)%、(94.18±3.26)%;与对照组和空白组相比,过表达组miR-10b表达升高,低表达组miR-10b表达降低,差异均有统计学意义(P<0.05),且对照组和空白组miR-10b表达差异无统计学意义(P>0.05);与对照组和空白组相比,过表达组NK细胞不同效靶比杀伤活性均降低、NKG2D表达降低,低表达组NK细胞不同效靶比杀伤活性均增高、NKG2D表达增高,差异均有统计学意义(P<0.05),各组NK细胞杀伤活性均随效靶比增加而增高,差异均有统计学意义(P<0.05),且对照组与空白组相比,相同效靶比NK细胞杀伤活性、NKG2D表达差异均无统计学意义(P>0.05);与对照组和空白组相比,过表达组人脑胶质瘤细胞U251表面MICA、ULBP2、ULBP3表达均降低,低表达组人脑胶质瘤细胞U251表面MICA、ULBP2、ULBP3表达均增高,差异均有统计学意义(P<0.05),且对照组与空白组人脑胶质瘤细胞U251表面MICA、ULBP2、ULBP3表达差异均无统计学意义(P>0.05)。结论:抑制miR-10b表达能够增加NK细胞表面NKG2D和人脑胶质瘤细胞U251表面MICA、ULBP2、ULBP3表达,增强NK细胞对人脑胶质瘤细胞U251的杀伤活性。 展开更多
关键词 微小核糖核酸-10b 脑胶质瘤 NK细胞激活受体 主要组织相容性复合物Ⅰ链相关基因A ul16结合蛋白2 ul16结合蛋白3
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地震统计区地震活动性参数b值和ν_(4)计算分析−以华北地区为例
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作者 沈得秀 王庆民 +2 位作者 许洪泰 葛孚刚 蒋其峰 《震灾防御技术》 CSCD 北大核心 2024年第2期241-252,共12页
本文通过收集最新现代地震资料,采用历史地震与现代地震联合求取地震活动性参数的方法,按不同地震统计时段和震级段,基于Matlab程序中给定函数计算并拟合了华北平原地震统计区、郯庐地震统计区、长江下游-南黄海地震统计区、汾渭地震统... 本文通过收集最新现代地震资料,采用历史地震与现代地震联合求取地震活动性参数的方法,按不同地震统计时段和震级段,基于Matlab程序中给定函数计算并拟合了华北平原地震统计区、郯庐地震统计区、长江下游-南黄海地震统计区、汾渭地震统计区的b值和ν_(4),并将结果与五代图推荐的b值和ν_(4)进行地震危险性分析对比,进而分析最新现代地震资料对b值和ν_(4)的影响。研究结果对地震统计区确定b值和ν_(4)有一定参考意义,对地震区划、工程场地地震安全性评价、省级地震危险性区划编制工作具有实际意义。 展开更多
关键词 地震活动性参数 b ν_(4) 华北地区
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唐山老震区M≥4.0地震前b值变化异常特征研究
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作者 岳晓媛 李艳娥 +3 位作者 钟世军 王薇 王燕 马梁 《地震》 CSCD 北大核心 2024年第1期94-108,共15页
选取2009年1月至2022年12月唐山老震区的地震目录资料计算b值,利用格点搜索法确定b值下降幅度较大(≥20%)的区域作为异常区,分析该区域b值的时间变化特征,结合b值的时空变化研究该区域发生M4.0以上地震的危险性。研究发现,唐山老震区7次... 选取2009年1月至2022年12月唐山老震区的地震目录资料计算b值,利用格点搜索法确定b值下降幅度较大(≥20%)的区域作为异常区,分析该区域b值的时间变化特征,结合b值的时空变化研究该区域发生M4.0以上地震的危险性。研究发现,唐山老震区7次(组)M4.0以上地震均发生在b值下降幅度较大的区域边缘或附近,表明应力较高的区域是地震危险区。异常区域内b值的时间变化显示,7次(组)M4.0以上地震多在震前半年至一年出现b值下降的变化过程,也反映了异常区域应力逐渐积累的过程。总体来说,b值的时空下降变化对唐山老震区M4.0以上地震的研判具有指示意义。 展开更多
关键词 唐山老震区 异常特征 b 格点搜索
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Detection of hyper-conserved regions in hepatitis B virus X gene potentially useful for gene therapy 被引量:7
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作者 Carolina González David Tabernero +12 位作者 Maria Francesca Cortese Josep Gregori Rosario Casillas Mar Riveiro-Barciela Cristina Godoy Sara Sopena Ariadna Rando Marcal Yll Rosa Lopez-Martinez Josep Quer Rafael Esteban Maria Buti Francisco Rodríguez-Frías 《World Journal of Gastroenterology》 SCIE CAS 2018年第19期2095-2107,共13页
AIM To detect hyper-conserved regions in the hepatitis B virus(HBV) X gene(HBX) 5' region that could be candidates for gene therapy.METHODS The study included 27 chronic hepatitis B treatmentnaive patients in vari... AIM To detect hyper-conserved regions in the hepatitis B virus(HBV) X gene(HBX) 5' region that could be candidates for gene therapy.METHODS The study included 27 chronic hepatitis B treatmentnaive patients in various clinical stages(from chronic infection to cirrhosis and hepatocellular carcinoma, both HBeA g-negative and HBeA g-positive), and infected with HBV genotypes A-F and H. In a serum sample from each patient with viremia > 3.5 log IU/m L, the HBX 5' end region [nucleotide(nt) 1255-1611] was PCRamplified and submitted to next-generation sequencing(NGS). We assessed genotype variants by phylogenetic analysis, and evaluated conservation of this region by calculating the information content of each nucleotide position in a multiple alignment of all unique sequences(haplotypes) obtained by NGS. Conservation at the HBx protein amino acid(aa) level was also analyzed.RESULTS NGS yielded 1333069 sequences from the 27 samples, with a median of 4578 sequences/sample(2487-9279, IQR 2817). In 14/27 patients(51.8%), phylogenetic analysis of viral nucleotide haplotypes showed a complex mixture of genotypic variants. Analysis of the information content in the haplotype multiple alignments detected 2 hyper-conserved nucleotide regions, one in the HBX upstream non-coding region(nt 1255-1286) and the other in the 5' end coding region(nt 1519-1603). This last region coded for a conserved amino acid region(aa 63-76) that partially overlaps a Kunitz-like domain.CONCLUSION Two hyper-conserved regions detected in the HBX 5' end may be of value for targeted gene therapy, regardless of the patients' clinical stage or HBV genotype. 展开更多
关键词 HEPATITIS b virus HEPATITIS b X GENE HEPATITIS b X protein GENE therapy Next-generation sequencing HbV CONSERVED regions Small interference RNA
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Mutations in hepatitis B virus core regions correlate with hepatocellular injury in Chinese patients with chronic hepatitis B 被引量:3
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作者 Hiroto Tanaka Hiroki Ueda +9 位作者 Hiroko Hamagami Susumu Yukawa Masakazu Ichinose Motoshige Miyano Keiji Mimura Iwao Nishide Bo-Xin Zhang Su-Wen Wang Shi-Oing Zhou Bei-Hai Li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第30期4693-4696,共4页
AIM: To elucidate the relationship between the frequency of core mutations and the clinical activity of hepatitis B virus (HBV)-related liver disease and to characterize the amino acid changes in the core region of HB... AIM: To elucidate the relationship between the frequency of core mutations and the clinical activity of hepatitis B virus (HBV)-related liver disease and to characterize the amino acid changes in the core region of HBV.METHODS: We studied 17 Chinese patients with chronic hepatitis B according to their clinical courses and patterns of the entire core region of HBV.RESULTS: Amino acid changes often appeared in the HBV core region of the HBV gene in patients with high values of alanine aminotransferase (ALT) or with the seroconversion from HbeAg to anti-HBe. The HBV core region with amino acid changes had high frequency sites that corresponded to HLA Ⅰ/Ⅱ restricted recognition epitopes reported by some investigators.CONCLUSION: The core amino acid changes of this study occur due to influence of host immune system. The presence of mutations in the HBV core region seems to be important for predicting the clinical activity of hepatitis B in Chinese patients. 展开更多
关键词 基因突变 乙肝病毒 中心区域 肝细胞损伤 中国 慢性肝炎
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Assessment of Climate Variability and Agricultural Activities in the Area of Tadla Plain
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作者 Yousra El Baki Khalid Boutoial Abdelouahid Medaghri-Alaoui 《Journal of Geoscience and Environment Protection》 2023年第11期1-26,共26页
The variations in both precipitation and temperature have far-reaching effects on agricultural activities and the accessibility of water resources. These climatic parameters are pivotal in determining the availability... The variations in both precipitation and temperature have far-reaching effects on agricultural activities and the accessibility of water resources. These climatic parameters are pivotal in determining the availability of both groundwater and surface water for agricultural use. The aim of this study was to evaluate the variations in climate parameters, focusing on precipitation and temperature, alongside changes in cultivated land area and crop yields in the Tadla area (Béni Mellal Khénifra region, Morocco);additionally, our research looks at the changes in water inflow into two dams and four aquifers. Trends were assessed over the period of 2010-2020 using the standardized precipitation index (SPI) method, as well as the parametric regression method and nonparametric Mann-Kendall and Sen’s slope test. This analysis can be a preliminary step in demonstrating the effects of climate variability on water resource availability and its adverse impacts on agriculture in the region. The results showed a decreasing trend for some yield crops despite the increase in the cultivated area. The results of the groundwater levels and inflow dams showed a significant upward evolution. The analysis of the obtained SPI values and temperatures has revealed a notable and consistent upward trendencies. This upward trajectory indicates that both the SPI values, which reflect precipitation patterns and the temperatures, have been on the rise over the examined period. These results prompt reflection on the effects of climate variability on water resources in the region and economic activities, particularly agriculture. 展开更多
关键词 béni Mellal Khénifra region GROUNDWATER Mann Kendal Method Regression Groundwater Levels Standardized Precipitation Index
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基于线粒体Cyt b基因和D-loop区分析元江鲤和杞麓鲤群体遗传结构
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作者 张铭枭 赵玉姣 +6 位作者 姚创 刘霄 黄松茂 李红涛 代忠礼 武祥伟 孔令富 《水产学杂志》 CAS 2024年第3期13-21,共9页
本文利用线粒体Cyt b基因和D-loop区部分序列,分析元江鲤(Cyprinus carpio yuankiang)和杞麓鲤(Cyprinus carpio chilia)群体的遗传结构。结果表明,在两个鲤群体中均获得929 bp的Cyt b基因序列和650 bp的D-Loop区序列。两个群体间平均... 本文利用线粒体Cyt b基因和D-loop区部分序列,分析元江鲤(Cyprinus carpio yuankiang)和杞麓鲤(Cyprinus carpio chilia)群体的遗传结构。结果表明,在两个鲤群体中均获得929 bp的Cyt b基因序列和650 bp的D-Loop区序列。两个群体间平均遗传距离为0.00595(Cyt b)、0.00852(D-loop)。Cyt b基因共检测出元江鲤3种、杞麓鲤15种单倍型,两个群体共享两个单倍型(C-Hap1和C-Hap3);D-loop区序列共检测出元江鲤3种、杞麓鲤6种单倍型,两个群体共享两个单倍型(D-Hap1和D-Hap2)。元江鲤和杞麓鲤群体单倍型多样性(Hd)分别为0.30±0.10(Cyt b)、0.25±0.10(D-loop)和0.89±0.04(Cyt b)、0.73±0.05(D-loop)。元江鲤和杞麓鲤群体核苷酸多样性(π)分别为0.12±0.04(Cyt b)、0.12±0.09(D-loop)和0.77±0.09(Cyt b)、0.87±0.07(D-loop),杞麓鲤遗传多样性水平明显高于元江鲤群体。分子方差分析(AMOVA)显示,两个群体间有明显的遗传分化,且遗传变异主要来源于群体间。系统发育分析显示,元江鲤群体单倍型较少,类型较单一,与杞麓鲤群体差异大,多数元江鲤样本单倍型属于华南鲤(Cyprinus carpio rubrofuscus)类型;多数杞麓鲤样本具特有单倍型,部分属于华南鲤、远东鲤(Cyprinus carpio haematopterus)类型。结果表明,杞麓鲤与元江鲤群体遗传分化明显,元江鲤线粒体遗传多样性较低。 展开更多
关键词 元江鲤 杞麓鲤 Cyt b基因 D-LOOP区 群体遗传结构 遗传多样性
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左束支区域起搏对心室起搏患者心脏功能、血浆BNP水平及心律失常发生率的影响
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作者 胡钦 韩卫卫 +3 位作者 梁洁 周峰 计承 刘金波 《中国心血管病研究》 CAS 2024年第6期549-553,共5页
目的 探讨左束支区域起搏(LBBP)对心室起搏患者心脏功能、血浆B型脑钠肽(BNP)水平及心律失常发生率的影响。方法 回顾性分析2021年5月至2023年5月就诊于石家庄市人民医院的62例需心室起搏的患者,按心脏起搏电极植入部位不同分为LBBP组(3... 目的 探讨左束支区域起搏(LBBP)对心室起搏患者心脏功能、血浆B型脑钠肽(BNP)水平及心律失常发生率的影响。方法 回顾性分析2021年5月至2023年5月就诊于石家庄市人民医院的62例需心室起搏的患者,按心脏起搏电极植入部位不同分为LBBP组(32例)和右心室间隔部起搏(RVSP)组(30例),比较两组心脏功能[左心室射血分数(LVEF)、左心房容积指数(LAVI)、三尖瓣环收缩期位移(TAPSE)、二尖瓣环处舒张早期峰值流速(Ea)、二尖瓣口舒张早期的血流峰值速度(E)与二尖瓣环舒张早期峰值速度(Ea)的比值(E/Ea)]、起搏参数及QRS波时限、血浆BNP和6 min步行试验(6-MWT)和心律失常发生率。结果 术后6个月,RVSP组LVEF、TAPSE相比术前RVSP组和术后6个月LBBP组均降低(P<0.05),术后6个月RVSP组LAVI、E/Ea相比术前RVSP组和术后6个月LBBP组均升高(P<0.05)。术后1周、术后1个月、术后6个月LBBP组和RVSP组起搏参数(阈值、感知、阻抗)比较均无明显差异(P>0.05)。术后1周、术后1个月、术后6个月LBBP组QRS波时限均低于RVSP组(P<0.05)。两组术后心律失常发生率比较差异不明显(P>0.05)。结论 与RVSP相比,LBBP应用于心室起搏患者可有效降低术后血浆BNP水平和QRS波时限,有助于心脏功能的改善。 展开更多
关键词 心室起搏 左束支区域起搏 心脏功能 血浆b型脑钠肽 心律失常
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鸭肠炎病毒UL6基因B细胞表位的预测及其主要抗原域的原核表达 被引量:6
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作者 孙涛 程安春 +3 位作者 汪铭书 郭宇飞 贾仁勇 沈婵娟 《中国兽医科学》 CAS CSCD 北大核心 2008年第11期939-945,共7页
采用DNAStar Protean程序,综合运用二级结构、亲水性、可塑性和抗原性指数等参数,对鸭肠炎病毒(DEV)CHv毒株UL6基因(GenBank登录号EF055890)的氨基酸序列进行了B细胞表位预测。结果显示,UL6蛋白羧基端第Thr507~Gln515、Thr521~... 采用DNAStar Protean程序,综合运用二级结构、亲水性、可塑性和抗原性指数等参数,对鸭肠炎病毒(DEV)CHv毒株UL6基因(GenBank登录号EF055890)的氨基酸序列进行了B细胞表位预测。结果显示,UL6蛋白羧基端第Thr507~Gln515、Thr521~Met529、Asp531~Phe539、Gly544~Asn562、Thr568~Gln585、Lys592~Val604、A1a681~Ala778和Tyr780~Lys790区域内含有优势B细胞表位。以DEV CHv毒株基因组作为PCR模板,利用Oligo6.0软件设计了1对引物,整体扩增涵盖上述具有优势表位的基因片段,将其亚克隆到原核表达载体pET-32a(+)中,获得表达载体pET-32a—UL6M,再将其转化至E.coli Rosetta(DE3),经IPTG诱导,外源基因获得了良好表达。以免抗DEV多克隆血清进行Western blot分析,抗血清可与该融合蛋白发生特异性反应。提示,该氨基酸片段可能含有软件预测的线性表位区。 展开更多
关键词 鸭肠炎病毒 ul6基因 b细胞表位预测 抗原域 原核表达
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人巨细胞病毒UL/b’区基因多态性
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作者 阮强 《临床儿科杂志》 CAS CSCD 北大核心 2007年第7期524-527,共4页
人巨细胞病毒(human cytomegalovirus,HCMV)在人群中普遍感染,在新生儿中,HCMV先天感染可引起黄疸性肝炎、先天性巨结肠、小头畸形等各种消化系统和神经系统畸形。导致HCMV不同致病性的发病机制还不十分清楚,一方面与宿主免疫功能,即有... 人巨细胞病毒(human cytomegalovirus,HCMV)在人群中普遍感染,在新生儿中,HCMV先天感染可引起黄疸性肝炎、先天性巨结肠、小头畸形等各种消化系统和神经系统畸形。导致HCMV不同致病性的发病机制还不十分清楚,一方面与宿主免疫功能,即有效的细胞及体液免疫应答有关;另一方面与病毒的数量、入侵部位及病毒自身的基因结构相关,尤其是与病毒毒力、组织嗜性和病毒逃避机体免疫攻击能力密切相关的基因关系密切。对于HCMV基因多态性的研究可以在基因层面揭示不同来源临床株的结构特点,对全面认识HCMV基因组和进一步深入研究基因组功能具有重要意义,成为HCMV研究的热点领域之一。近年来,国际多个研究小组对HCMV临床株广泛存在而旧有实验室株缺失的UL/b’区基因进行了较系统的研究,取得了较快的进展。此专题对这方面的研究进展进行概要介绍,以供同行了解与深入研究。 展开更多
关键词 巨细胞病毒 基因多态性 ul/b’区基因
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多参数预测人巨细胞病毒临床病毒株UL145基因B细胞表位
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作者 伍苑宾 胡兢晶 +2 位作者 王波 苏海浩 谭琪琪 《中国现代医生》 2020年第35期27-30,共4页
目的应用多参数预测及分析人巨细胞病毒(Human cytomegalovirus,HCMV)临床病毒株UL145基因B细胞表位。方法根据人巨细胞病毒UL145基因氨基酸序列预测其二级结构,结合跨膜结构、亲水性、可及性及抗原性方案等参数综合预测UL145基因B细胞... 目的应用多参数预测及分析人巨细胞病毒(Human cytomegalovirus,HCMV)临床病毒株UL145基因B细胞表位。方法根据人巨细胞病毒UL145基因氨基酸序列预测其二级结构,结合跨膜结构、亲水性、可及性及抗原性方案等参数综合预测UL145基因B细胞表位。结果HCMV pUL145氨基酸等电点为6.64,二级结构以无规则卷为主,1~130位氨基酸均为膜外区域,结合多种预测方法分析提示,88~99位氨基酸序列内可作为HCMV UL145基因的B细胞候选表位。结论多参数预测提示88~99位氨基酸序列为HCMV UL145基因B细胞表位预测序列,为进一步制备相应的抗体提供了重要依据。 展开更多
关键词 人巨细胞病毒 ul145 b细胞表位 生物信息学分析
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Interleukin-10 promoter polymorphisms in patients with hepatitis B virus infection or hepatocellular carcinoma in Chinese Han ethnic population 被引量:9
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作者 Juan Wang, Hong Ni, Li Chen and Wen-Qin Song College of Life Sciences, Nankai Umversity, Tianjin 300071. China and College of Life Sciences, Shenzhen University, Shenzhen 518060, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2006年第1期60-64,共5页
BACKGROUND: Since single nucleotide polymorphisms (SNPs) can serve as gene markers, polymorphism profiles may help scientists to identify the full collection of genes that contribute to the development of complex dise... BACKGROUND: Since single nucleotide polymorphisms (SNPs) can serve as gene markers, polymorphism profiles may help scientists to identify the full collection of genes that contribute to the development of complex diseases such as cancer. The distribution of interleukin-10 (IL-10) promoter polymorphisms in Chinese Han ethnic patients with hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC) was investigated in this study. METHODS: The polymorphisms of IL-10 promoter region were detected by pulymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and sequencing. Sixty-six health controls, 42 patients with HBV infection, 30 HCC patients, and cell line SMMC-7721 were examined this way. RESULTS: Polyrnorphisms of T/C or T/N on-872 site occurred frequently in Han ethnic population. Pulyrnorphisms were detected in HBV and HCC patients and cell line SMMC-7721. The hotspot among the pulymorphisms was inserting base A between-1058 and-1057. CONCLUSION: Polymorphisms of IL-10 promoter in HBV and HCC patients may be associated with HBV infection and HCC development. 展开更多
关键词 INTERLEUKIN-10 polymorphisms on promoter region polymerase chain reaction-single strand conformation polymorphism hepatitis b virus carcinoma hepatocellular
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人巨细胞病毒UL23基因编码蛋白的B细胞表位预测
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作者 朱峰 李弘剑 +4 位作者 李月琴 何智强 李实骞 张欣 周天鸿 《中国现代医学杂志》 CAS CSCD 北大核心 2009年第21期3231-3234,共4页
目的预测人巨细胞病毒UL23基因编码蛋白的B细胞表位。方法应用互联网软件分析Hopp&Woods亲水性(Hydrophilicity)、可及性(Accessibility)、极性(Polarity)及柔韧性(Flexibility)、Welling抗原性(Antigenicity)和二级结构(Secondary ... 目的预测人巨细胞病毒UL23基因编码蛋白的B细胞表位。方法应用互联网软件分析Hopp&Woods亲水性(Hydrophilicity)、可及性(Accessibility)、极性(Polarity)及柔韧性(Flexibility)、Welling抗原性(Antigenicity)和二级结构(Secondary structures)等参数,用吴玉章等建立的B细胞表位预测法综合评价。结果多种预测法重复了人巨细胞病毒UL23开放阅读框编码蛋白的N端第27~43、104~119、125~160位氨基酸区域内或附近,该区域含有β转角和无规卷曲结构,极可能是B细胞识别表位。结论为应用合成肽或原核表达大片断蛋白制备抗人巨细胞病毒UL23基因编码蛋白的抗体提供了依据。 展开更多
关键词 人巨细胞病毒 ul23 b细胞表位 预测
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Analysis of hepatitis B virus preS1 variability and prevalence of the rs2296651 polymorphism in a Spanish population 被引量:5
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作者 Rosario Casillas David Tabernero +9 位作者 Josep Gregori Irene Belmonte Maria Francesca Cortese Carolina González Mar Riveiro-Barciela Rosa Maria López Josep Quer Rafael Esteban Maria Buti Francisco Rodríguez-Frías 《World Journal of Gastroenterology》 SCIE CAS 2018年第6期680-692,共13页
AIM To determine the variability/conservation of the domain of hepatitis B virus(HBV) pre S1 region that interacts with sodium-taurocholate cotransporting polypeptide(hereafter, NTCP-interacting domain) and the preval... AIM To determine the variability/conservation of the domain of hepatitis B virus(HBV) pre S1 region that interacts with sodium-taurocholate cotransporting polypeptide(hereafter, NTCP-interacting domain) and the prevalence of the rs2296651 polymorphism(S267 F, NTCP variant) in a Spanish population. METHODS Serum samples from 246 individuals were included and divided into 3 groups: patients with chronic HBV infection(CHB)(n = 41, 73% Caucasians), patients with resolved HBV infection(n = 100, 100% Caucasians) and an HBV-uninfected control group(n = 105, 100% Caucasians). Variability/conservation of the amino acid(aa) sequences of the NTCPinteracting domain,(aa 2-48 in viral genotype D) and a highly conserved pre S1 domain associated with virion morphogenesis(aa 92-103 in viral genotype D) were analyzed by next-generation sequencing and compared in 18 CHB patients with viremia > 4 log IU/mL. The rs2296651 polymorphism was determined in all individuals in all 3 groups using an in-house real-time PCR melting curve analysis.RESULTS The HBV pre S1 NTCP-interacting domain showed a high degree of conservation among the examined viral genomes especially between aa 9 and 21(in the genotype D consensus sequence). As compared with the virion morphogenesis domain, the NTCPinteracting domain had a smaller proportion of HBV genotype-unrelated changes comprising > 1% of the quasispecies(25.5% vs 31.8%), but a larger proportion of genotype-associated viral polymorphisms(34% vs 27.3%), according to consensus sequences from Gen Bank patterns of HBV genotypes A to H. Variation/conservation in both domains depended on viral genotype, with genotype C being the most highly conserved and genotype E the most variable(limited finding, only 2 genotype E included). Of note, proline residues were highly conserved in both domains, and serine residues showed changes only to threonine or tyrosine in the virion morphogenesis domain. The rs2296651 polymorphism was not detected in any participant.CONCLUSION In our CHB population, the NTCP-interacting domain was highly conserved, particularly the proline residues and essential amino acids related with the NTCP interaction, and the prevalence of rs2296651 was low/null. 展开更多
关键词 HEPATITIS b VIRUS HEPATITIS b VIRUS PRES1 region sodium-taurocholate co-transporting polypeptide NTCP-interacting DOMAIN VIRION morphogenesis DOMAIN SNP rs2296651 next-generation sequencing real-time PCR melting curves
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A mutation of the start codon in the X region of hepatitis B virus DNA in a patient with non-B,non-C chronic hepatitis 被引量:3
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作者 Kiyotaka Fujise Keiko Tatsuzawa +6 位作者 Midori Kono Sadayori Hoshina Akihito Tsubota Minoru Niiya Yoshihisa Namiki Norio Tada Hisao Tajiri 《World Journal of Hepatology》 CAS 2011年第2期56-60,共5页
There are cases of hepatitis involving occult hepatitis B virus(HBV)infection in which,even though the HB surface antigen(HBsAg)is negative,HBV-DNA is detected by a polymerase chain reaction(PCR).We con-ducted a seque... There are cases of hepatitis involving occult hepatitis B virus(HBV)infection in which,even though the HB surface antigen(HBsAg)is negative,HBV-DNA is detected by a polymerase chain reaction(PCR).We con-ducted a sequence analysis of the entire HBV region in a case of non-B non-C chronic hepatitis in a 46-yearold female.A diagnosis of non-B non-C chronic hepatitis was made.Although HBV markers,such as HBs antibody(anti-HBs),anti-HBc,HBeAg and anti-HBe,were negative,HBV-DNA was positive.Nested PCR was performed to amplify the precore region of HBV-DNA and all remaining regions by long nested PCR.Sequence analysis of the two obtained bands was conducted by direct sequencing.Compared with the control strains,the ATG(Methionine)start codon in the X region had mut ated to GTG(Valine).It is assumed that a mutation at the start codon in the X region may be the reason why HBV markers are negative in some cases of hepatitis that involve occult HBV infection. 展开更多
关键词 HEPATITIS b virus X region MUTATION Non-b non-C chronic HEPATITIS Occult infection
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缩骨鲫Cyt b基因和控制区序列克隆及系统进化分析
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作者 李强 郑鹏 +5 位作者 黄文炜 彭苏汉 周江伟 詹华伟 蓝昭军 桂林 《湖南农业科学》 2023年第10期7-10,25,共5页
研究通过Sanger测序法对天然雌核发育的缩骨鲫(Carassius auratus var. Suogu)线粒体DNA的Cyt b基因和控制区进行扩增和测序,并与已发表的其他鲫属鱼类的Cyt b基因进行系统进化分析,探讨缩骨鲫与其他鲫属鱼类的系统进化关系。结果表明:... 研究通过Sanger测序法对天然雌核发育的缩骨鲫(Carassius auratus var. Suogu)线粒体DNA的Cyt b基因和控制区进行扩增和测序,并与已发表的其他鲫属鱼类的Cyt b基因进行系统进化分析,探讨缩骨鲫与其他鲫属鱼类的系统进化关系。结果表明:缩骨鲫线粒体DNA中Cyt b基因和控制区全序列分别长1 141和924 bp;其中,Cyt b基因的碱基含量为29.1%(T)、27.9%(C)、28.7%(A)和14.3%(G),控制区序列的碱基含量为32.6%(T)、20.7%(C)、32.6%(A)和14.1%(G);2种序列中G+C含量均明显低于A+T含量,且G含量偏低,显示了与其他脊椎动物线粒体核苷酸碱基含量相似的特征;控制区序列可以分为终止序列区、中央保守区和保守序列区3个区域,均识别到了对应的保守序列;基于邻接法(NJ)和最大简约法(MP)构建缩骨鲫与其他鲫属鱼类Cyt b基因的系统进化树表明,缩骨鲫与红鲫和淇河鲫的亲缘关系最近,而缩骨鲫与野鲫、淇河鲫和红鲫分布在同一个姐妹支系,进一步说明缩骨鲫可能起源于野鲫,是野鲫的一个地方种群。 展开更多
关键词 缩骨鲫 细胞色素b基因 控制区 系统进化分析
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Role of the virion host shutoff protein in neurovirulence of monkey B virus(Macacine herpesvirus 1) 被引量:1
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作者 Darla Black Jerry Ritchey +1 位作者 Mark Payton Richard Eberle 《Virologica Sinica》 SCIE CAS CSCD 2014年第5期274-283,共10页
Monkey B virus(Macacine herpesvirus 1; BV) is noted for its extreme neurovirulence in humans. Since the vhs protein encoded by the UL41 gene has been shown to be a neurovirulence factor in the related human herpes sim... Monkey B virus(Macacine herpesvirus 1; BV) is noted for its extreme neurovirulence in humans. Since the vhs protein encoded by the UL41 gene has been shown to be a neurovirulence factor in the related human herpes simplex viruses, the role of the UL41 gene in BV neurovirulence was investigated. BV mutants were constructed that lacked the entire UL41 ORF(Δ41) or had the RNase active site mutated(Δ41A). Neither mutant shut off host protein synthesis, degraded β-actin mRNA, or prevented an IFN-β response, indicating that the vhs protein and its RNase activity are both necessary for these activities. Replication of both mutants in primary mouse cells was impaired and they exhibited a prolonged disease course in mice. Whereas Δ41 infected mice were euthanized for symptoms related to central nervous system(CNS) infection, Δ41A infected mice were euthanized primarily for symptoms of autonomic nervous system dysfunction. While neuroinvasiveness was not affected, lesions in the CNS were more limited in size, anatomical distribution, and severity than for wild-type virus. These results indicate that the vhs protein affects the general replicative efficiency of BV in vivo rather than being a specific neurovirulence factor critical for invasion of or preferential replication in the CNS. 展开更多
关键词 HERPESVIRUS MONKEY b virus ul41 VIRION HOST shutoff NEUROVIRulENCE
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Molecular Epidemiological Analysis of Echovirus 19 Isolated From an Outbreak Associated With Hand, Foot, and Mouth Disease (HFMD) in Shandong Province of China 被引量:22
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作者 ZHEN ZHU WEN-BO XU +6 位作者 AI-QIANG XU HAI-YAN WANG YONG ZHANG LI-ZHI SONG Hui-LiYANG YANLI FENGJI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第4期321-328,共8页
To elucidate the genetic characterization and molecular epidemiological features of Echovirus 19 (El9) isolates collected from an outbreak associated with hand, foot and mouth disease (HFMD) in Tai'an city of Sha... To elucidate the genetic characterization and molecular epidemiological features of Echovirus 19 (El9) isolates collected from an outbreak associated with hand, foot and mouth disease (HFMD) in Tai'an city of Shandong Province of China from July to September, 2003. Methods Thirty seven Echovirus 19 isolates were isolated from stool specimens and throat swabs collected during the outbreak, then major capsid (VP1) genomic sequence was determined, and phylogenetic tree was done based on the VP1 sequences among these 37 and other El9 viruses deposited in the Genbank. Also a representative strain named CHN-SD03-TN12 was selected for sequencing of 5′-untranslated regions (5′-UTR). Results The identity rate was about 98.9%-100% among all these 37 El9 viruses. The genetic relationships between these 37 El9 isolates and other strains reported were also depicted. The identity rate was about 78.4%-78.9% compared with El9 reference strain Burke. The substitutions in the sequence of 5′-UTR resulted in changes in the conjectural properties of 5′-UTR of El9 viruses. Condusion The genetic features of El9 viruses isolated during the outbreak in Shandong Province in 2003 may be associated with a genetic and antigenic drift that changes the virulence of the Shandong isolates, but the molecular changes in Shandong El9 viruses contributing to their phenotype remain to be further illuminated. However, the sequences described in this paper substantiate the changes taken place in capsid VPI and 5′UTR regions. These substitutions may contribute to their tropism and virulence, and play a significant role in pathogenesis and clinical manifestations of the disease. 展开更多
关键词 Enterovirus 19(E19) Hand foot and mouth disease (HFMD) Molecular epidemiology 5′ Untranslated regions(5′-UTR) b-C loop
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UL 1699B《光伏直流电弧故障保护电器》标准解析 被引量:4
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作者 钱广远 《电器与能效管理技术》 2019年第9期71-75,共5页
近年来,针对交流线路的电弧故障保护电器(AFDD)产品已经日趋成熟并广泛应用,但针对直流线路的AFDD产品才刚起步。简单介绍了UL1699B4光伏直流电弧故障保护电器》的发展历史,并对该标准中的关键试验过程进行解读分析,期望能够对光伏直流A... 近年来,针对交流线路的电弧故障保护电器(AFDD)产品已经日趋成熟并广泛应用,但针对直流线路的AFDD产品才刚起步。简单介绍了UL1699B4光伏直流电弧故障保护电器》的发展历史,并对该标准中的关键试验过程进行解读分析,期望能够对光伏直流AFDD产品的制造商提供帮助指导。 展开更多
关键词 电弧故障保护电器(AFDD) 光伏直流系统 ul 1699b 电气火灾
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Chronic hepatitis B liver disease in patients living in the Amazon region: S gene mutations and genotypes characterization 被引量:1
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作者 Deusilene Vieira Marie Gauthier +6 位作者 Larissa Deadame de Figueiredo Nicolete Alcione Oliveira dos Santos Carina Picelli Eduardo Honda Glaucia Paranhos-Baccala Guy Vernet Juan Miguel Villalobos Salcedo 《World Journal of Cardiovascular Diseases》 2013年第8期506-511,共6页
The Amazon region is considered to be a high endemic area for Hepatitis B Virus (HBV) infections, Rond&ocirc;nia state having the highest prevalence. The aim of this study was to identify molecular genotypes and m... The Amazon region is considered to be a high endemic area for Hepatitis B Virus (HBV) infections, Rond&ocirc;nia state having the highest prevalence. The aim of this study was to identify molecular genotypes and mutations in the S gene region of HBV viral genomes from 20 patients using a DNA microarray. Results: Serological tests showed that 88% of patients were HBeAg negative, 82% had anti-HBe antibodies and 33% were co-infected with Hepatitis Delta Virus. Sixteen percent of the patients were considered cirrhotic, and 11% have been transfused. The microarray technique identified the genotypes A (4 patients), D (7 patients) and F (7 patients) in 18 samples. Mutations were detected in all 3 genotypes and, overall, A159G, which has been associated with a reduced antigenicity of the virus, was detected most frequently. In genotype A, G119E was the most frequently detected mutation followed by mutations A159G, F134Y, W172C, Y161F and T143S. A159G was detected in all genotype D and F samples followed by mutations T143S, Y161F, N131T, T114S and G119E in genotype D and mutations T143S, Y161F, N131T, T114S and G119E in genotype F. Conclusion: The analysis of mutations repartition among genotypes suggests that some of them are preferentially or exclusively associated with genotype A, D or F. This type of tool is adapted for clinical and therapy monitoring of patient as well as for molecular epidemiology research on HBV. 展开更多
关键词 Hepatitis b Virus Mutant Detection DNA Microarray Amazon region
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