鳄蜥对熟悉和陌生个体气味的辨别

个体辨别对于减少同种争斗以及配偶选择具有重要意义。我们用棉棒粘取鳄蜥(Shinisaurus crocodilurus)尿液作为气味源,以香水作为对照,测定鳄蜥对熟悉个体气味、陌生个体气味以及香水的舔舌次数和舔舌潜伏期,来探讨鳄蜥通过化学信息辨别熟悉和陌生个体的能力。结果显示,不论是雌性还是雄性,对不同个体尿液的舔舌次数均显著高于对香水的,舔舌潜伏期显著短于香水的;尽管雄性对陌生同性个体气味与熟悉同性个体气味的舔舌次数无显著差异,但对前者的舔舌潜伏期显著短于后者;雄性对陌生雌性气味的舔舌次数显著多于熟悉雌性气味的,对前者的舔舌潜伏期显著短于后者;雌性对陌生雄性气味的舔舌潜伏期显著短于对熟悉雄性气味的;雄鳄蜥对陌生雌性气味的舔舌次数显著多于雌鳄蜥对陌生雄性的。结果表明,鳄蜥能辨别同种个体的化学信息,并能通过化学信息来辨别熟悉和陌生个体,推测鳄蜥的这种辨别能力对其领域分配以及繁殖交配有重要作用。     

象山港日本对虾增殖放流的效果评价

日本对虾是中国近海重要的增殖品种,2010年象山港分两批次放流日本对虾苗种约1.67亿尾。通过对放流苗种存活状况、洄游分布、生长特性及回捕情况的跟踪调查,对象山港日本对虾的增殖效果做出初步评价。结果表明:(1)日本对虾放流苗种在8月中旬成为补充群体,集中于港区底部进行索饵育肥;9月中旬,第1、2批放流苗种的平均体长分别达到95.4 mm和71.4 mm,成活率分别约为0.79%和1.06%;10月上旬,随着港区水温降低,增殖苗种资源量锐减。(2)协方差分析表明:日本对虾增殖群体和自然群体的体长-体重关系存在显著性差异,增殖群体的体征状况明显优于自然群体。(3)日本对虾放流苗种在港区主要为桁杆拖虾和地笼网渔业所利用,在港区滞留期间,回捕率约为0.25%。总结发现:栖息地破坏及放流苗种的过早利用是制约象山港日本对虾增殖效果的重要因素,优化增殖策略、保护港区生态环境应是今后港区增殖工作的重点。     

2D differential in-gel electrophoresis for the identification of esophageal scans cell cancer-specific protein markers

The reproducibility of conventional two-dimensional (2D) gel electrophoresis can be improved using differential in-gel electrophoresis (DIGE), a new emerging technology for proteomic analysis. In DIGE, two pools of proteins are labeled with 1-(5-carboxypentyl)-1'-propylindocarbocyanine halide (Cy3) N-hydroxy-succinimidyl ester and 1-(5-carboxypentyl)-1'-methylindodi-carbocyanine halide (Cy5) N-hydroxysuccinimidyl ester fluorescent dyes, respectively. The labeled proteins are mixed and separated in the same 2D gel. 2D DIGE was applied to quantify the differences in protein expression between laser capture microdissection-procured esophageal carcinoma cells and normal epithelial cells and to define cancer-specific and normal-specific protein markers. Analysis of the 2D images from protein lysates of approximately 250,000 cancer cells and normal cells identified 1038 protein spots in cancer cell lysates and 1088 protein spots in normal cell lysates. Of the detected proteins, 58 spots were up-regulated by >3-fold and 107 were down-regulated by >3-fold in cancer cells. In addition to previously identified down-regulated protein annexin I, tumor rejection antigen (gp96) was found up-regulated in esophageal squamous cell cancer. Global quantification of protein expression between laser capture-microdissected patient-matched cancer cells and normal cells using 2D DIGE in combination with mass spectrometry is a powerful tool for the molecular characterization of cancer progression and identification of cancer-specific protein markers.     

尖吻蝮咬伤与心脏损害：附20例分析

本文报告尖吻蝮咬伤并心脏受累20例。经中西医结合治愈19例(95％),死亡1例(5％),并对其发病机理及治疗进行了讨论。     

也门铁的组织培养技术研究

以4品种也门铁的茎段为外植体进行组织培养技术研究。结果表明,控制普通也门铁茎段褐化效果最理想的培养基为MS + 0.25 g·L-1 VC + 0.50 g·L-1 Na2S2O3;诱导也门铁不定芽萌动的最佳培养基为MS + 3.0 mg·L-1 6-BA + 0.2 mg·L-1 NAA + 0.1 mg·L-1 KT;诱导也门铁不定芽增殖的最佳培养基,因品种不同而异,普通也门铁和金心也门铁为MS + 2.0 mg·L-1 6-BA + 1.0 mg·L-1 NAA + 0.1 mg·L-1 GA3,扭纹铁和金心扭纹铁为MS + 1.0 mg·L-1 6-BA + 0.5 mg·L-1 NAA + 0.1 mg·L-1 GA3;也门铁壮苗的最佳培养基为MS + 0.05 mg·L-1 6-BA + 0.05 mg·L-1 NAA + l g·L-1AC;也门铁生根最优培养基为1/2MS + 0.5 mg·L-1 IBA。     

Destructive Changes in the Neuronal Structure of the FVB/N Mouse Retina

We applied a series of selective antibodies for labeling the various cell types in the mammalian retina. These were used to identify the progressive loss of neurons in the FVB/N mouse, a model of early onset retinal degeneration produced by a mutation in the pde6b gene. The immunocytochemical studies, together with electroretinogram (ERG) recordings, enabled us to examine the time course of the degenerative changes that extended from the photoreceptors to the ganglion cells at the proximal end of the retina. Our study indicates that photoreceptors in FVB/N undergo a rapid degeneration within three postnatal weeks, and that there is a concomitant loss of retinal neurons in the inner nuclear layer. Although the loss of rods was detected at an earlier age during which time M- and S-opsin molecules were translocated to the cone nuclei; by 6 months all cones had also degenerated. Neuronal remodeling was also seen in the second-order neurons with horizontal cells sprouting processes proximally and dendritic retraction in rod-driven bipolar cells. Interestingly, the morphology of cone-driven bipolar cells were affected less by the disease process. The cellular structure of inner retinal neurons, i.e., ChAT amacrine cells, ganglion cells, and melanopsin-positive ganglion cells did not exhibit any gross changes of cell densities and appeared to be relatively unaffected by the massive photoreceptor degeneration in the distal retina. However, Muller cell processes began to express GFAP at their endfeet at p14, and it climbed progressively to the cell’s distal ends by 6 months. Our study indicates that FVB/N mouse provides a useful model with which to assess possible intervention strategies to arrest photoreceptor death in related diseases.     

高通量测序技术及其在微生物学研究中的应用

20世纪70年代发明的核酸测序技术为基因组学及其相关学科的发展做出了巨大贡献,本世纪初发展的以Illumina公司的HiSeq 2000,ABI公司的SOLID,和Roche公司的454技术为代表的高通量测序技术又为基因组学的发展注入了新活力.本文在阐述这些技术的基础上,着重讨论了新一代测序技术在微生物领域中的应用.     

Identification of new human cadherin genes using a combination of protein motif search and gene finding methods

We have combined protein motif search and gene finding methods to identify genes encoding proteins containing specific domains. Particularly, we have focused on finding new human genes of the cadherin superfamily proteins, which represent a major group of cell-cell adhesion receptors contributing to embryonic neuronal morphogenesis. Models for three cadherin protein motifs were generated from over 100 already annotated cadherin domains and used to search the complete translated human genome. The genomic sequence regions containing motif "hits" were analyzed by eukaryotic GeneMark.hmm to identify the exon-intron structure of new genes. Three new genes CDH-J, PCDH-J and FAT-J were found. The predicted proteins PCDH-J and FAT-J were classified into protocadherin and FAT-like subfamilies, respectively, based on the number and organization of cadherin domains and presence of subfamily-specific conserved amino acid residues. Expression of FAT-J was shown in almost all tested tissues. The exon-intron organization of CDH-J was experimentally verified by PCR with specifically designed primers and its tissue-specific expression was demonstrated. The described methodology can be applied to discover new genes encoding proteins from families with well-characterized structural and functional domains.     

A systems-biology analysis of feedback inhibition in the Sho1 osmotic-stress-response pathway

BACKGROUND: A common property of signal transduction systems is that they rapidly lose their ability to respond to a given stimulus. For instance in yeast, the mitogen-activated protein (MAP) kinase Hog1 is activated and inactivated within minutes, even when the osmotic-stress stimulus is sustained. RESULTS: Here, we used a combination of experimental and computational analyses to investigate the dynamic behavior of Hog1 activation in vivo. Computational modeling suggested that a negative-feedback loop operates early in the pathway and leads to rapid attenuation of Hog1 signaling. Experimental analysis revealed that the membrane-bound osmosensor Sho1 is phosphorylated by Hog1 and that phosphorylation occurs on Ser-166. Moreover, Sho1 exists in a homo-oligomeric complex, and phosphorylation by Hog1 promotes a transition from the oligomeric to monomeric state. A phosphorylation-site mutation (Sho1(S166E)) diminishes the formation of Sho1-oligomers, dampens activation of the Hog1 kinase, and impairs growth in high-salt or sorbitol conditions. CONCLUSIONS: These findings reveal a novel phosphorylation-dependent feedback loop leading to diminished cellular responses to an osmotic-stress stimulus.