Müller细胞在视网膜绿光损伤模型中的激活反应

目的研究Müller细胞在大鼠视网膜绿光损伤模型中的激活反应。方法 72只出生后8周(约230～280g)的成年雄性Sprague-Dawley大鼠随机分9组。一组作为正常对照,另8组暗适应24 h后置于波长为(530±10)nm的LED灯光箱中照射3 h,并分别于暗恢复3、6、12 h及1、2、3、7、15 d取眼球,光学显微镜下观察同一定位处视网膜组织形态、检测(TUNEL)凋亡细胞、免疫组织化学染色及蛋白免疫印迹分析。结果光损伤后光感受器内外节变短,外核层变薄,细胞排列紊乱;细胞凋亡出现在外核层,暗恢复3 h出现,3 d时达到高峰,7 d时消失;胶质细胞纤维酸性蛋白(glial fibrillary acidic protein,GFAP)表达量于暗恢复12 h开始升高,随暗恢复时间延长逐渐升高;谷氨酰胺合成酶(glutaminesynthetase,GS)总表达量未见明显改变,但可见蛋白一过性重分布,表达部位由内核层移至外核层。pSTAT3蛋白表达量于损伤后12 h出现一过性升高。结论绿光损伤视网膜激活Müller细胞,pSTAT3可能参与了此激活过程。     

Very early and transient vegetal-plate expression of SpKrox1, a Krüppel/Krox gene from Strongylocentrotus purpuratus

All endodermal and mesenchymal cells of the sea urchin embryo descend from the vegetal plate, a thickened epithelium of approximately 50 cells arising at the early blastula stage. Cell types that derive from the vegetal plate are specified conditionally by inductive interactions with underlying micromeres, but the molecular details of vegetal-plate specification remain unresolved. In a search for regulatory proteins that have roles in vegetal-plate specification, a screen was performed to clone Krüppel/Krox-related genes from a Strongylocentrotus purpuratus embryo cDNA library. One newly identified clone, named SpKrox1, contained four zinc fingers and a leucine zipper domain. SpKrox1 expression was low in unfertilized eggs, increased severalfold to the early blastula stage and decreased between the early gastrula and pluteus stages. SpKrox1 mRNA was first seen in macromeres of 16-cell stage embryos and was restricted to cells of the developing vegetal plate thereafter. Vegetal-plate expression corresponded to a ring of cells around the blastopore and overlapped the expression patterns of other genes with potential roles in vegetal plate-specification. As the vegetal-plate cells invaginated into the blastopore, SpKrox1 expression was lost, suggesting that its role was not in endoderm differentiation per se but rather in the initial establishment of the vegetal plate.     

Biomass allocation and leaf stoichiometric characteristics in four desert herbaceous plants during different growth periods in the Gurbantünggüt Desert,China

荒漠草本植物是荒漠生态系统物种多样性的主体, 对其生物量分配及叶片化学计量特征随植物生长的变化规律的研究有助于深入了解荒漠草本植物生存策略和功能特征。该文选择古尔班通古特沙漠4种优势草本(2种短命植物, 2种一年生长营养期植物)为研究对象, 通过野外原位多时段取样, 对比研究了四者生物量分配、叶片N-P化学计量学随植物生长的变化特征, 以及二者之间的关系。结果表明, 在生物量累积过程中, 4种植物根冠比逐渐减小, 地上与地下生物量间的相关生长关系也发生变化, 其中琉苞菊(Hyalea pulchella)和角果藜(Ceratocarpus arenarius)的相关生长指数先增加后减小, 并趋于稳定, 而尖喙牻牛儿苗(Erodium oxyrrhynchum)和沙蓬(Agriophyllum squarrosum)的相关生长指数由小到大并趋于等速生长。琉苞菊叶片N、P含量呈逐渐增长趋势, 而另外3种植物呈下降趋势, 表明所研究的荒漠植物在生长过程中, 叶片N-P化学计量发生改变, 叶片化学计量特征与生物量指标的相关性较弱。     

Detection of QTLs for crossability in wheat using a doubled-haploid population

 An intervarietal molecular-marker map was used for the detection of genomic regions influencing crossability between wheat (Triticum aestivum L. em Thell) and rye (Secale cereale L.). Analysis of deviance and logistic marker-regression methods were conducted on data from doubled haploid lines from a cross between “Courtot” and “Chinese Spring”. A major quantitative trait locus (QTL) involved in crossability, associated with the marker Xfba367-5B, was detected on the short arm of chromosome 5B. An additional locus, Xwg583-5B, was indicated on the long arm of chromosome 5B. This minor QTL might correspond to Kr1 which was presumed to be the major gene controlling crossability. Another locus of the genome, Xtam51-7A on chromosome 7A, was significantly associated with this trait. Alleles of “non-crossability” were contributed by the non-crossable cultivar “Courtot”. The three-marker model explains 65% of the difference in crossability between the two parents. The present results are discussed in relation to those previously carried out to locate the Kr genes by using the telocentric mapping technique. Received: 27 February 1998 / Accepted: 15 May 1998     

New Materials of Navicula ( Naviculaceae) from Anhui,China

In this paper, a new species, a new variety and a new record for china of Navicula from Anhui Province are reported. They are Navicula anhuinsis sp. nov. and N. muticaKütz. var. sinica var. nov. and N. mutica var. stigma Patrick.     

中红侧沟茧蜂寄主——二龄棉铃虫幼虫血淋巴成分的初步分析

对二龄棉铃虫Ｈｅｌｉｏｔｈｉｓａｒｍｉｇｅｒａ（Ｈüｂｎｅｒ）幼虫血淋巴的二种样品（去血细胞和未去血细胞）中的干物重、含水量、灰分、蛋白质、总糖、还原糖、总脂、胆固醇、维生素Ｃ的含量,分别进行了定量分析,对未去血细胞的血淋巴进行了氨基酸测定;同时,对蛋白质组份、脂类组份也进行了定性分析