Hybridization kinetics on microarray surfaces

Kinetic hybridization data are compared to a number of different models. A first-order Langmuir model provides the best fit to the data.     

Cardiomyocyte apoptosis in autoimmune cardiomyopathy: mediated via endoplasmic reticulum stress and exaggerated by norepinephrine

Evidence suggests that the autoimmune cardiomyopathy produced by a peptide corresponding to the sequence of the second extracellular loop of the beta(1)-adrenergic receptor (beta(1)-EC(II)) is mediated via a biologically active anti-beta(1)-EC(II) antibody, but the mechanism linking the antibody to myocyte apoptosis and cardiac dysfunction has not been well elucidated. Since the beta(1)-EC(II) autoantibody is a partial beta(1)-agonist, we speculate that the cardiomyopathy is produced by the beta(1)-receptor-mediated stimulation of the CaMKII-p38 MAPK-ATF6 signaling pathway and endoplasmic reticulum (ER) stress, and that excess norepinephrine (NE) exaggerates the cardiomyopathy. Rabbits were randomized to receive beta(1)-EC(II) immunization, sham immunization, NE pellet, or beta(1)-EC(II) immunization plus NE pellet for 6 mo. Heart function was measured by echocardiography and catheterization. Myocyte apoptosis was determined by terminal deoxytransferase-mediated dUTP nick-end labeling and caspase-3 activity, whereas CaMKII, MAPK family (JNK, p38, ERK), and ER stress signals (ATF6, GRP78, CHOP, caspase-12) were measured by Western blot, immunohistochemistry, and kinase activity assay. beta(1)-EC(II) immunization produced progressive LV dilation, systolic dysfunction, and myocyte apoptosis. These changes were associated with activation of GRP78 and CHOP and increased cleavage of caspase-12, as well as increased CaMKII activity, increased phosphorylation of p38 MAPK, and nucleus translocation of cleaved ATF6. NE pellet produced additive effects. In addition, KN-93 and SB 203580 abolished the induction of ER stress and cell apoptosis produced by the beta(1)-EC(II) antibody in cultured neonatal cardiomyocytes. Thus ER stress occurs in autoimmune cardiomyopathy induced by beta(1)-EC(II) peptide, and this is enhanced by increased NE and caused by activation of the beta(1)-adrenergic receptor-coupled CaMKII, p38 MAPK, and ATF6 pathway.     

云南傣族、汉族HLA-G基因14bp插入/缺失多态性研究

14bp插入/缺失多态性是指存在于HLA-G基因第8外显子3′非翻译区(3′UTR)的一个插入/缺失多态,因其能影响HLA-GmRNA的稳定性,并进一步影响HLA-G蛋白的翻译而受到广泛关注。文章采用PCR和电泳技术对云南傣族和汉族两个人群进行了HLA-G基因14bp插入/缺失多态性的检测分析,结果显示傣族和汉族人群+14bp等位基因频率分别为31.97%和40.87%,+14bp/+14bp基因型频率分别为8.20%和17.31%,+14bp/-14bp基因型频率分别为47.54%和47.11%。与国内外已报道的其他人群的数据比较表明:云南汉族群体中HLA-G基因14bp插入/缺失的分布与其他群体相似;傣族则有自己独特的基因型和等位基因分布特点,推测其可能受到了遗传漂变的作用,但不排除自然选择作用的影响。     

海水浸泡开放性犬颅脑爆震伤影像学模型的建立

目的:建立海水浸泡开放性犬颅脑爆震伤影像学模型。方法:本实验采用新型球形爆炸源。狗颅中线向左(右)1cm,眶上缘向上1cm交界处为爆炸中心位置。爆炸距离(爆炸源最低点距爆炸点的距离)分别为3mm,3.5mm,4mm。比较各个距离的爆炸效果,选出最适的爆炸距离。在动物最适爆炸距离致伤后用吊瓶装满海水(秋季福建沿海距岸边200米深部海水),用皮管固定于伤口空洞中,使受伤脑组织始终浸泡于海水环境中。分别于3h,5h,8h行颅脑CT检查。观察海水浸泡开放性颅脑爆震伤的CT动态变化。结果:爆炸距离3.5mm为最适爆炸距离,此距离爆炸致伤后犬存活率高,能够炸开颅骨,使脑组织暴露,海水浸泡爆震伤口8小时,脑水肿逐渐出现。结论:本实验所建立的动物模型可模拟真实海战下冲击波致伤,且重复性和稳定性好,易操作,适用于海战情况下颅脑爆震伤的实验研究。     

小桐子愈伤组织的诱导

本文以小桐子的叶片、叶柄、茎段及下胚轴和子叶作为外植体,研究不同外植体类型对愈伤组织诱导的影响,结果表明叶柄的诱导率最高,其次为茎段的诱导率。同时以小桐子的下胚轴作为外植体,研究植物生长调节剂种类及浓度配比对愈伤组织诱导的影响,结果显示6-BA与2,4-D的组合更适宜小桐子愈伤组织的诱导,MS+6-BA0.5mg/L+2,4-D0.1mg/L为小桐子愈伤组织诱导的最佳培养基,其愈伤组织诱导率高达96.7%。本研究为小桐子愈伤组织的分化、植株再生及相关的遗传转化研究提供了参考。     

利用核糖体小亚基RNA基因序列对环须虫属,突口虫属及旋口虫属(原生动物,纤毛门,异毛纲)系统地位的探讨

在系统发育研究中,异毛纲纤毛虫普遍被认为是一个多源发生系.为进一步探讨纲中各科/属间的亲缘关系,新测定了隶属于异毛纲的2属4种的核糖体小亚基基因序列,并结合GenBank中迄今所知该类群的基因序列,利用最大似然法、贝叶斯法、最大简约法和邻接法构建了系统发生树.结果显示:1)所涉及的9个科中,赭纤虫科Blepharismidae、喇叭纤虫科Stentoridae、瓶囊虫科Folliculinidae和缘棘虫科Peritromidae为单源发生,爽口虫科Climacostomidae、旋口虫科spirostomidae和突口虫科Condylostomatidae为非单源发生;2)环须虫属Peritromus与爽口虫属Climacostomum两个属为姐妹类群;3)旋口虫属跏Spirostomum先于其它异毛类分化出去,与格鲁博虫属Gruberia亲缘关系较远;4)突喇叭虫属Condylostentor与突口虫属Condylostoma聚在一起并与夏通属Chattonidium具有更近的亲缘关系,而与喇叭虫属Stentor关系较远.     

Expression analysis of miRNAs and highly-expressed small RNAs in two rice subspecies and their reciprocal hybrids

Heterosis,or hybrid vigor,is the phenomenon whereby progeny of two inbred lines exhibit superior agronomic performance compared with either parent.We analyzed the expression of miRNAs and highly expressed small RNAs(defined according to Solexa sequencing results)in two rice(Oryza sativa)subspecies(japonica cv.Nipponbare and indica cv.93-11)and their reciprocal hybrids using microarrays.We found that of all the 1141 small RNAs tested,140(12%,140 of 1141)and 157(13%,157 of 1141)were identified being significantly differentially expressed in two reciprocal hybrids,respectively.All possible modes of action,including additive,high- and low- parent,above high- and below low-parent modes were exhibited.Both F1 hybrids showed non-additive expression patterns,with downregulation predominating.Interestingly,15 miRNAs displayed stark opposite expression trends relative to midparent in reciprocal hybrids.Computational prediction of targets of differentially expressed miRNAs showed that they participated in multifaceted developmental pathways,and were not distinguishable from the targets of non-differentially expressed miRNAs.Together,our findings reveal that small RNAs play roles in heterosis and add a new layer in the understanding and exploitation of molecular mechanisms of heterosis.     

荧光偏振技术在生命科学中的研究进展

荧光偏振技术(FP)作为一种新的检测技术已经广泛应用于生命科学的各个方面.本文对荧光偏振技术在生命科学中的研究进展做了详细的评述.介绍了荧光偏振技术的原理,评述了荧光偏振技术在生命科学中的研究热点方向.     

中国学术期刊网络出版总库节点文献新疆驴脑组织尼帕病毒N基因片段的检测

目的检测新疆伊犁草原地区放养新疆驴的脑组织样本中尼帕病毒（Nipah Virus,NiV）核蛋白（N）基因片段,调查该地区放养新疆驴NiV感染流行状况。方法采用一步法实时荧光定量逆转录聚合酶链反应（one-step Real-Time FQ RT-PCR）对采自新疆伊犁地区草原放养且未接种NiV疫苗的65例新疆驴脑组织进行NiVN基因片段检测。结果新疆驴脑组织标本中未检出NiV N基因片段。结论目前尚无证据表明我国新疆伊犁地区新疆驴中存在NiV感染,提示该地区短时间内爆发该病毒感染可能性较小。     

成釉质细胞分化机制的研究进展

牙齿的发育是由牙上皮和神经脊来源的间充质之间的连续的相互诱导产生的.上皮和间充质之间连续的相互诱导,使得上皮细胞分化为具有分泌牙釉质功能的成釉质细胞,而间充质细胞分化为具有分泌牙本质功能的成牙本质细胞.成釉质细胞的正常分化对于形成正常的牙釉质是至关重要的,本文主要对细胞信号分子、细胞黏附分子、釉质特异性基因和转录因子等在成釉质细胞分化过程中的作用做一概述.