微小隐孢子虫20K亲环蛋白基因克隆及分析

目的 克隆微小隐孢子虫(Cp)南京株(NJ)的20K亲环蛋白(CyP)基因,并对其核苷酸和氨基酸序列进行分析.方法 采用昆明种小鼠建立微小隐孢子虫NJ株感染模型,根据微小隐孢子虫Iowa Ⅱ株20K CyP基因序列设计合成2对引物,应用巢式PCR技术从微小隐孢子虫NJ株基因组DNA中扩增20K CyP基因,并将其克隆到pMD18-T载体上,将阳性克隆重组质粒进行菌落PCR及双酶切鉴定;应用生物信息学方法分析微小隐孢子虫NJ株20K CyP基因与其他虫株核苷酸和氨基酸序列差异,并分析该基因蛋白结构域.结果 巢式PCR扩增得到特异的20K CyP基因,经PCR及双酶切鉴定获得了正确的pMD18-T-20K CyP重组质粒;测序结果显示,微小隐孢子虫NJ株20K CyP基因全长519 bp,编码173个氨基酸,该基因已登录GenBank,登录号为JQ284431;氨基酸序列分析表明,微小隐孢子虫NJ株与Iowa Ⅱ株20K CyP基因编码的氨基酸序列具有100％同源性;对20K Cyp基因进行蛋白结构域分析,显示该基因序列所编码的蛋白具有特异性类亲环蛋白A、B、H的肽脯氨酰顺反异构酶(PPIase)区域,该区域与人的亲环蛋白A、B、H具有相似性.结论 成功克隆微小隐孢子虫NJ株20K CyP基因,该基因具有高度保守性.     

腰果主要过敏原Anao2基因克隆及原核表达

目的 克隆腰果主要过敏原Anao2基因,并利用pMAL-c表达载体表达该蛋白.方法 提取腰果总RNA,设计特异性引物,反转录-聚合酶链反应(RT-PCR)克隆腰果Anao2基因,将其反转录基因连入pMD18Tsimple vector,提取质粒、双酶切、鉴定并测序;将测序正确的片段连入原核表达载体pMAL-c,将重组质粒转入BL21宿主表达菌中,丙基-β-D-硫代吡喃半乳糖苷诱导表达目的蛋白Anao2.结果 测序结果表明克隆腰果Anao2基因片段全长为1 332 bp,编码443个氨基酸,与GenBank中蛋白序列完全相同;对获得的重组蛋白进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳鉴定,目的蛋白大小与理论值相符.结论 成功克隆并表达了腰果过敏原Anao2.     

牛带绦虫ATE基因功能预测及原核表达

目的 分析和预测牛带绦虫成虫精氨酰-Trna转移酶(arginyl-Trna-protein transferase,ATE)基因及其编码蛋白的结构域特性,并进行原核表达.方法 利用在线生物信息学网站及工具对牛带绦虫精氨酰-Trna转移酶基因的功能进行预测并将其编码区序列克隆到原核表达载体Pet-28a(+)上,测序鉴定重组质粒.结果 该基因全长1 476 bp,编码区为141～1 617 bp,编码491个氨基酸;该基因为全长基因,无跨膜区,具有多个磷酸化位点,蛋白的理化性质稳定,理论分子量为56 436.3Da;没有质体、线粒体定位序列;十二烷基一聚丙烯酰胺凝胶电泳(SDS-PAGE)结果表明,目的基因在大肠埃希菌BL21-DE3中表达成功.结论 筛选出牛带绦虫成虫精氨酰-Trna转移酶基因,成功构建重组原核表达质粒.     

猪带绦虫成虫EF-1基因生物信息分析及原核表达

目的 分析和预测牛带绦虫成虫精氨酰-Trna转移酶(arginyl-Trna-protein transferase,ATE)基因及其编码蛋白的结构域特性,并进行原核表达.方法 利用在线生物信息学网站及工具对牛带绦虫精氨酰-Trna转移酶基因的功能进行预测并将其编码区序列克隆到原核表达载体Pet-28a(+)上,测序鉴定重组质粒.结果 该基因全长1 476 bp,编码区为141～1 617 bp,编码491个氨基酸;该基因为全长基因,无跨膜区,具有多个磷酸化位点,蛋白的理化性质稳定,理论分子量为56 436.3Da;没有质体、线粒体定位序列;十二烷基一聚丙烯酰胺凝胶电泳(SDS-PAGE)结果表明,目的基因在大肠埃希菌BL21-DE3中表达成功.结论 筛选出牛带绦虫成虫精氨酰-Trna转移酶基因,成功构建重组原核表达质粒.     

基于克隆表达的芳香烃受体系统的二噁(口英)生物检测方法研究

目的 研究人工克隆表达的芳香烃受体核转位蛋白(ARNT)与天然芳香烃受体(AhR)特异性结合及其对制备的多克隆抗体识别的情况,通过两者结合与二噁(口英)(TCDD)的剂量反应关系,探索TCDD生物检测方法.方法 (1)以小鼠肝组织总RNA为模板,通过RT-PCR扩增目的 基因AhR-PAS[periodicity(Per)/Aryl hydrocarbon nuclear translocatar(ARNT)/single-minded(Sim)]端、AhR羧基末端(AhR-C端)、ARNT-PAS端,构建含有目的 基因的pGEX-5X1重组表达质粒,并采用大肠杆菌原核系统进行克隆表达.(2)用上述克隆表达的AhR片段蛋白(AhR-PAS、AhR-C)作为抗原免疫家兔,制备多克隆抗体.(3)从C57BL/6J纯系小鼠肝组织中提取具有结合活性的天然AhR复合物,将天然AhR复合物与结合在谷胱甘肽硫转移酶(GST)上面的融合蛋白GST-ARNT-PAS,分别在0.25、0.50、1.00、2.00 pmol TCDD存在的条件下进行结合,通过亲和吸附和免疫印迹观察所形成的蛋白复合物的量.结果 (1)成功构建含有目的 基因AhR-PAS、AhR-C和ARNT-PAS的重组质粒,并通过大肠杆菌原核系统表达出具有结合活性的目的 蛋白;(2)免疫家兔制得的多克隆抗体AhR-PAS、AhR-C的检测下限分别为5、1 ng;(3)测得该法制备的小鼠肝脏匀浆中总蛋白质的浓度为60.5 mg/ml;在TCDD存在的条件下,克隆得到的融合蛋白GST-ARNT-PAS能够与天然AhR复合物特异性地结合,并测得检测下限为0.25 pmol,约80 Pg TCDD.结论 成功地建立了基于克隆表达的芳香烃受体系统的TCDD生物检测方法,且检测下限达到pg级别.     

猪囊尾蚴排泄分泌抗原LRRC15蛋白的原核表达及多克隆抗体制备

目的构建猪带绦虫重组质粒pET30a-富含亮氨酸重复序列(LRR)结构域15(LRRC15), 原核表达纯化的LRRC15重组蛋白, 制备兔多克隆抗体。方法采用全基因合成方法, 获得猪带绦虫LRRC15蛋白编码基因;将其克隆至pET30a载体, 构建重组质粒pET30a-LRRC15, 并进行双酶切PCR鉴定;将重组质粒转化至大肠埃希菌BL21(DE3)感受态细胞, 用异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达LRRC15重组蛋白, 十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)分析鉴定表达产物;用Ni-IDA亲和层析柱纯化LRRC15重组蛋白, SDS-PAGE进行分析鉴定;蛋白质印迹法(Western blot, WB)鉴定纯化重组蛋白特异性;用纯化的LRRC15重组蛋白免疫新西兰兔, 制备LRRC15多克隆抗体, 用间接酶联免疫吸附试验(ELISA)测定纯化多克隆抗体的效价。结果经PCR鉴定, 扩增出长度为1 506 bp的条带, 与LRRC15基因相符;经SDS-PAGE和WB鉴定, 获得相对分子质量(Mr)约为55.36 × 103的LRRC15目的蛋白;用LR...     

金黄色葡萄球菌类肠毒素W的超抗原活性位点预测与克隆表达

目的预测金黄色葡萄球菌类肠毒素W(SElW)与T细胞受体(TCR)的对接和超抗原活性位点, 并对SElW进行克隆表达和纯化。方法利用AlphaFold对SElW蛋白单体进行三维结构预测, 借助SAVES在线服务器使用ERRAT、拉氏图和Verify₃D等软件对蛋白模型进行评估。用ZDOCK服务器模拟SElW与TCR的对接构象, 并对SElW与其他肠毒素的氨基酸序列进行比对。设计引物扩增selw基因, 将该片段重组于pMD18-T载体中并进行测序;经限制性内切酶BamHⅠ和Hind Ⅲ双酶切后将目的片段重组于表达质粒pET-28a(+)中, 重组质粒鉴定后用IPTG诱导表达;用亲和层析法对表达于上清中的SElW蛋白进行纯化, 用BCA法对蛋白进行定量。结果三维结构预测结果显示, SElW蛋白由氨基末端和羧基末端两个结构域组成, 其中氨基末端结构域由3个α-螺旋和6个β-片层组成, 羧基末端结构域由2个α-螺旋和7个反向平行的β-片层组成。SElW蛋白模型的整体质量因素得分为98.08, 其中93.24%的氨基酸Verify₃D得分≥0.2, 且...     

家蝇热休克蛋白HSP20基因克隆、表达和序列分析

目的对家蝇热休克蛋白20(HSP20)基因进行生物信息学分析,并进行克隆、表达研究。方法利用美国国家生物技术信息中心和瑞士生物信息学研究所的蛋白分析专家系统中有关基因和蛋白序列的分析工具,结合其他生物信息学分析软件包,从Gen Bank上家蝇基因组序列识别出编码HSP20的基因,分析预测该蛋白质的结构功能;设计引物PCR扩增HSP20基因,将其克隆到原核表达质粒PEASY-E1中,重组质粒在大肠杆菌Origmi B/DE3中经用异丙硫代-β-D半乳糖苷(IPTG)诱导表达,表达产物用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDSPAGE)鉴定。结果 HSP20基因序列全长865bp,最大开放阅读框(ORF)为567bp,编码188个氨基酸,理论分子量为21443.2 Da,等电点为5.96;所构建的重组质粒经PCR、双酶切及测序鉴定成功;SDS-PAGE分析结果显示,重组质粒在Origmi B/DE3中表达并纯化,得到的融合蛋白相对分子质量约为21443.2 Da,诱导12 h蛋白表达量最高,SDS-PAGE法得到的蛋白条带与目的蛋白大小相符。结论成功构建PEASY-E1-HSP20重组原核表达质粒并表达出融合HSP20蛋白,为进一步研究该蛋白的功能奠定基础。     

亚洲牛带绦虫TaCRISP基因克隆、表达和序列分析

目的 通过筛选亚洲牛带绦虫(Taenia saginata asiatica)成虫cDNA质粒文库,识别半胱氨酸分泌蛋白(Ta CRISP),并进行克隆表达,为进一步研究其功能提供基础依据.方法 用生物信息学方法从亚洲牛带绦虫成虫全长cDNA质粒文库中识别TaCRISP的全长编码基因并预测编码蛋白质的各种结构与功能;将其编码区序列克隆到原核表达载体pET-30a(+)上,测序鉴定重组质粒,之后进行诱导表达,表达产物经十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)鉴定.结果 该基因全长1 090bp,编码239个氨基酸,1aa-16aa位为分泌信号肽,理论分子量为26 973.8,等电点为5.96.生物信息分析揭示,Ta CRISP与中殖孔绦虫CRISP一致性为38%,相似性为54%;所构建的重组体经PCR、双酶切及测序鉴定与目标基因相符.SDS-PAGE结果表明,目的 基因在大肠埃希菌BL-21/DE3中表达成功.结论 发现亚洲牛带绦虫Ta CRISP基因,成功构建重组原核表达质粒并表达出融合蛋白.     

口虾蛄原肌球蛋白基因表达及变应原性鉴定

目的 克隆口虾蛄原肌球蛋白(tropomyosin)基因并表达纯化出重组蛋白,研究其变应原性.方法 提取口虾蛄总RNA,设计特异引物,通过反转录聚合酶链反应克隆出目的 基因片段,测序后将该片段克隆到原核表达载体pET-28a上,转化到E coli BL21(DE3)后,经异丙基-B-D-硫代乳糖苷(IPTG)诱导表达,用Ni2+亲和层析柱对重组变应原进行纯化.采用免疫印迹(Western-blot)检测其与对虾过敏的患者血清IgE结合活性.结果 经序列测定,该基因含有长度为855bp的开放阅读框,编码284个氨基酸(GenBank登录号为EF584510).十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)检测该重组变应原在大肠埃希菌中高效表达36kDa的目的 蛋白,且重组变应原具有良好的IgE结合活性.结论 本研究成功获得了具有变应原活性的重组口虾蛄原肌球蛋白.     

Investigation and Control of Anthrax Outbreak at the Human–Animal Interface,Bhutan, 2010

In 2010, we investigated anthrax outbreak in Bhutan. A total of 43 domestic animals died, and cutaneous anthrax developed in 9 persons, and 1 died. All affected persons had contact with the carcasses of infected animals. Comprehensive preparedness and response guidelines are needed to increase public awareness of anthrax in Bhutan.     

Dengue Virus Transmission by Blood Stem Cell Donor after Travel to Sri Lanka; Germany, 2013

Three days after donation of peripheral blood stem cells to a recipient with acute myeloblastic leukemia, dengue virus was detected in the donor, who had recently traveled to Sri Lanka. Transmission to the recipient, who died 9 days after transplant, was confirmed.     

Risk for Travel-associated Legionnaires’ Disease,Europe, 2009

Legionnaires’ disease is underreported in Europe; notification rates differ substantially among countries. Approximately 20% of reported cases are travel-associated. To assess the risk for travel-associated Legionnaires’ disease (TALD) associated with travel patterns in European countries, we retrieved TALD surveillance data for 2009 from the European Surveillance System, and tourism denominator data from the Statistical Office of the European Union. Risk (number cases reported/number nights spent) was calculated by travel country. In 2009, the network reported 607 cases among European travelers, possibly associated with 825 accommodation sites in European Union countries. The overall risk associated with travel abroad was 0.3 cases/million nights. We observed an increasing trend in risk from northwestern to southeastern Europe; Greece had the highest risk (1.7). Our findings underscore the need for countries with high TALD risks to improve prevention and control of legionellosis; and for countries with high TALD risks, but low notification rates of Legionnaires’ disease to improve diagnostics and reporting.     

Travel-associated Diseases,Indian Ocean Islands, 1997–2010

Data collected by the GeoSentinel Surveillance Network for 1,415 ill travelers returning from Indian Ocean islands during 1997–2010 were analyzed. Malaria (from Comoros and Madagascar), acute nonparasitic diarrhea, and parasitoses were the most frequently diagnosed infectious diseases. An increase in arboviral diseases reflected the 2005 outbreak of chikungunya fever.     

Long-Term Survival Among Histological Subtypes in Advanced Epithelial Ovarian Cancer: Population-Based Study Using the Surveillance,Epidemiology, and End Results Database

BackgroundActual long-term survival rates for advanced epithelial ovarian cancer (EOC) are rarely reported.ObjectiveThis study aimed to assess the role of histological subtypes in predicting the prognosis among long-term survivors (≥5 years) of advanced EOC.MethodsWe performed a retrospective analysis of data among patients with stage III-IV EOC diagnosed from 2000 to 2014 using the Surveillance, Epidemiology, and End Results cancer data of the United States. We used the chi-square test, Kaplan–Meier analysis, and multivariate Cox proportional hazards model for the analyses.ResultsWe included 8050 patients in this study, including 6929 (86.1%), 743 (9.2%), 237 (2.9%), and 141 (1.8%) patients with serous, endometrioid, clear cell, and mucinous tumors, respectively. With a median follow-up of 91 months, the most common cause of death was primary ovarian cancer (80.3%), followed by other cancers (8.1%), other causes of death (7.3%), cardiac-related death (3.2%), and nonmalignant pulmonary disease (3.2%). Patients with the serous subtype were more likely to die from primary ovarian cancer, and patients with the mucinous subtype were more likely to die from other cancers and cardiac-related disease. Multivariate Cox analysis showed that patients with endometrioid (hazard ratio [HR] 0.534, P<.001), mucinous (HR 0.454, P<.001), and clear cell (HR 0.563, P<.001) subtypes showed better ovarian cancer-specific survival than those with the serous subtype. Similar results were found regarding overall survival. However, ovarian cancer–specific survival and overall survival were comparable among those with endometrioid, clear cell, and mucinous tumors.ConclusionsOvarian cancer remains the primary cause of death in long-term ovarian cancer survivors. Moreover, the probability of death was significantly different among those with different histological subtypes. It is important for clinicians to individualize the surveillance program for long-term ovarian cancer survivors.     

Raccoons and skunks as sentinels for enzootic tularemia

We analyzed sera from diverse mammals of Martha's Vineyard, Massachusetts, for evidence of Francisella tularensis exposure. Skunks and raccoons were frequently seroreactive, whereas white-footed mice, cottontail rabbits, deer, rats, and dogs were not. Tularemia surveillance may be facilitated by focusing on skunks and raccoons.     

Outbreak of Panton-Valentine Leukocidin–Associated Methicillin-Susceptible Staphylococcus aureus Infection in a Rugby Team,France, 2010–2011

Staphylococcus aureus strains that produce Panton-Valentine leukocidin are known to cause community infections. We describe an outbreak of skin abscesses caused by Panton-Valentine leukocidin–producing methicillin-susceptible S. aureus (clonal complex 121) in a professional rugby team in France during July 2010–February 2011. Eight team members were carriers; 7 had skin abscesses.     

Haemophilus ducreyi Associated with Skin Ulcers among Children,Solomon Islands

During a survey of yaws prevalence in the Solomon Islands, we collected samples from skin ulcers of 41 children. Using PCR, we identified Haemophilus ducreyi infection in 13 (32%) children. PCR-positive and PCR-negative ulcers were phenotypically indistinguishable. Emergence of H. ducreyi as a cause of nongenital ulcers may affect the World Health Organization’s yaws eradication program.     

大龄单身女性寻求生育力保存的伦理问题探析

近年来,在肿瘤和卵巢相关疾病发生率逐年增加、不少大龄单身女性渴望为自己购买一份“生殖保险”等社会及个人因素催化下,人类对于生育力保存的需求急剧增加,满足这一需求正在或将成为重大挑战。对于寻求进行生育力保存的大龄单身女性来说,在合适的年龄应用玻璃化冷冻技术将其卵母细胞冻存是目前可采用的最佳生育力保存手段。而单身女性卵子冷冻将面临来自伦理道德、社会乃至法律的巨大挑战。本文概述国内外大龄单身女性卵子冷冻的现状,并对其可能涉及的相关伦理问题及解决途径进行综述,以促进理性正视单身女性卵子冷冻问题。