Rapid evolution of disease resistance is accompanied by functional changes in gene expression in a wild bird

Wild organisms are under increasing pressure to adapt rapidly to environmental changes. Predicting the impact of these changes on natural populations requires an understanding of the speed with which adaptive phenotypes can arise and spread, as well as of the underlying mechanisms. However, our understanding of these parameters is poor in natural populations. Here we use experimental and molecular approaches to investigate the recent emergence of resistance in eastern populations of North American house finches (Carpodacus mexicanus) to Mycoplasma galliseptum (MG), a severe conjunctivitis-causing bacterium. Two weeks following an experimental infection that took place in 2007, finches from eastern US populations with a 12-y history of exposure to MG harbored 33% lower MG loads in their conjunctivae than finches from western US populations with no prior exposure to MG. Using a cDNA microarray, we show that this phenotypic difference in resistance was associated with differences in splenic gene expression, with finches from the exposed populations up-regulating immune genes postinfection and those from the unexposed populations generally down-regulating them. The expression response of western US birds to experimental infection in 2007 was more similar to that of the eastern US birds studied in 2000, 7 y earlier in the epizootic, than to that of eastern birds in 2007. These results support the hypothesis that resistance has evolved by natural selection in the exposed populations over the 12 y of the epizootic. We hypothesize that host resistance arose and spread from standing genetic variation in the eastern US and highlight that natural selection can lead to rapid phenotypic evolution in populations when acting on such variation.     

体外培养神经干细胞CNTF、TGF-β1和IGF-1的表达

目的研究培养神经干细胞（NSC）中CNTF,TGF-β1,IGF-1基因表达情况.方法取小鼠胎鼠海马,分离纯化培养NSC,提取总RNA,RT-PCR技术检测CNTF,TGF-β1,IGF mRNA的表达情况.结果培养NSC中各因子mRNA均有表达;CNTF,TGF-β1表达较强,IGF-1表达较弱.结论体外培养的NSC表达CNTF,TGF-β1含量较高,可能是应用其治疗神经疾病的理论基础.     

Paxillin和FAK mRNA在食管癌组织中的表达及临床意义

目的 研究桩蛋白(paxillin)和黏着斑激酶(focal adhesion kinase, FAK)mRNA在食管癌组织中的表达及其与临床病理学参数的关系,并分析两者在食管癌中表达的相关性.方法 运用RT-PCR技术检测59例食管癌组织、27例不典型增生组织和36例正常食管黏膜组织中paxillin和FAK mRN...     

2008-2010年哈尔滨市889例手足口病患者EV71病毒感染情况分析

目的了解2008-2010年哈尔滨市辖区医院收治的889例手足口病患者EV71病毒感染情况。方法采用两个样本率比较的假设检验,对889例手足口病患者咽拭子、粪便、肛拭子等标本RT-PCR或Real-time PCREV71核酸鉴定结果,按不同性别、不同居住地、不同年龄和不同发病时间分类进行比较,分析2008-2010年手足口病患者EV71感染情况。结果 3年合计,男性患者EV71阳性检出率高于女性(35.82%vs28.32%),农村患者阳性检出率最高(37.60%),城市(27.42%)与乡镇(27.36%)则相近;2~岁患者阳性检出率(37.56%)最高,其次为1~岁(34.98%)、3~岁(32.77%)和4~岁患者(32.69%),0~岁(29.63%)和5~岁(20.88%)相对较低;7月阳性检出率(38.11%)最高,其次为6月(35.48%)、5月(34.07%)。3年实验室监测确证EV71感染率分别为31.40%、25.00%和41.24%,3年间患者样本阳性检出率差异与分类情况有关。结论 2008-2010年哈尔滨市辖区医院收治的手足口病患者EV71阳性检出率按不同性别、不同居住地、不同年龄...     

应用荧光定量RT-PCR法检测牡蛎中诺如病毒

目的建立牡蛎样品中的诺如病毒检测方法。方法优化甘氨酸缓冲液处理牡蛎匀浆液,摸索PEG沉淀浓缩病毒的浓度,提取病毒RNA,采用荧光定量RT-PCR方法进行诺如病毒检测。应用优化后的方法检测105份牡蛎样本,并用核苷酸序列测定法对阳性PCR产物进行验证。结果甘氨酸缓冲液pH值为4.5,PEG沉淀浓度为16%时的诺如病毒富集提取效果最好,该方法的诺如病毒检出限为1.17×102个质粒拷贝。应用该方法对未知样本进行检测阳性率达14.29%,所得阳性PCR产物经核苷酸序列测序证实为诺如病毒。结论本研究方法可以应用于牡蛎中的诺如病毒检测,南宁市海鲜市场上的部分牡蛎含有诺如病毒。     

简单重复序列技术鉴别恶性疟原虫单/多重感染

目的建立快速鉴别恶性疟原虫样本单/多重感染的方法。方法从我国恶性疟流行区云南和海南两省采集恶性疟确诊患者血样共40份;采用巢式/半巢氏PCR方法对样本5个微卫星中立位点进行STR分型,任一微卫星位点出现两种或以上等位基因即划归为混合感染。结果共有38份样本成功进行了5个微卫星位点的等位基因分型,其中云南地区样本多重感染样本3份（7.89%）,海南地区1例（2.63%）。结论运用STR分型技术可快速有效地鉴别恶性疟原虫样本的单/多重感染类型。     

创伤后应激障碍大鼠海马组织5-HT1受体mRNA的表达

目的探讨创伤后应激障碍(posttraumatic stress disorder,PTSD)大鼠海马组织中5-羟色胺受体1mRNA的表达。方法随机将雄性Wistar大鼠分为对照组和PTSD组,采用改良的单一连续应激(SPS&S)方法刺激大鼠建立PTSD大鼠模型,Morris水迷宫实验检测大鼠记忆功能,化学发光法检测大鼠血清皮质醇浓度。建模后1d、4d、7d、14d分离海马组织,RT-PCR方法检测5-羟色胺受体1的变化。结果 (1)对照组水迷宫实验逃避潜伏期为(5.632±1.065)s,模型组为(20.762±3.236)s(t=9.932,P<0.01);(2)对照组血清皮质醇浓度为(1.25±0.12)μg/dl,模型组为(0.58±0.09)μg/dl(t=7.340,P<0.01);(3)应激后1d、4d、7d、14d海马5-HT1A受体mRNA表达相对水平分别为0.846±0.067、0.510±0.052、1.007±0.137、1.109±0.106,与对照组1.223±0.152相比较,1d、4d、7d表达低于对照组(P<0.05);5-羟色胺1受体其他亚型未见表达。结论 PTSD大鼠海马中5-HT1A受体mRNA表达降低。     

变应性哮喘患者外周血单个核细胞Tim-1 mRNA及Tim-3 mRNA表达及意义

目的研究Tim-1mRNA及Tim-3mRNA在变应性哮喘患者外周血单个核细胞(PBMC)的表达,探讨其在变应性哮喘发病中可能的作用。方法随机收集临床变应性哮喘患者25例,以健康体检者12例作为对照。采用实时荧光定量反转录-聚合酶链反应(RT-PCR)检测两组Tim-1mRNA和Tim-3的mRNA表达,并分析他们与哮喘临床表型之间的关系。结果 Tim-1mRNA和Tim-3mRNA在变应性哮喘患者PBMC中表达明显升高,差异有统计学意义(P<0.05),且与患者血清总IgE水平和临床严重程度相关,总IgE水平和临床严重程度分级越高,Tim-1mRNA和Tim-3mRNA表达越高(P<0.05)。结论 Tim-1mRNA和Tim-3mRNA在变应性哮喘患者中表达明显升高,Tim-1mRNA和Tim-3mRNA可能参与变应性哮喘的发生和发展。     

The role of NrCAM in neural development and disorders--beyond a simple glue in the brain

NrCAM is a neuronal cell adhesion molecule of the L1 family of immunoglobulin super family. It plays a wide variety of roles in neural development, including cell proliferation and differentiation, axon growth and guidance, synapse formation, and the formation of the myelinated nerve structure. NrCAM functions in cell adhesion and modulates signaling pathways in neural development through multiple molecular interactions with guidance and other factors. Alterations in NrCAM structure/expression are associated with psychiatric disorders such as autism and drug addiction and with tumor progression. The mechanisms of NrCAM participation in development and how these might be perturbed in disorders are reviewed.