用于脑缺血小鼠海马SOD1表达的改进灌注固定法

常规灌注固定法多用于兔和大鼠等较大动物,并存在一些不足。改进了灌注固定法流程、灌注溶液的配方、流速、用量以及灌注装置,将其用于在显微操作下制备的缺血再灌注C57BL/6N小鼠模型,并对其海马进行H.E染色和免疫组织化学SOD1基因表达。结果显示,改进的灌注固定法使组织切片结构更加清晰,海马免疫阳性神经元定位于胞浆。缺血再灌注组(24hI/R)海马神经元SOD1表达比假手术对照组(sham-o)减少,而高压氧治疗组(24hHBO)SOD1表达有所恢复。表明改进的灌注固定法用于缺血再灌注C57BL/6N小鼠海马SOD1基因表达效果良好,结果可靠。实验结果提示,高压氧的治疗机制之一可能是通过增加SOD1基因表达而实现的。     

6—DMAP和胚胎干细胞代数对异种重构卵体外发育的影响（简报）

The development of reconstructed oocytes and the survival rate of cloned animal were affected by many factors during nuclear transfer. The genetic constitution and the genetic state of donor nucleus were proposed to be primary factors, which affected the survival rate of cloned animal. In addition, the survival rate of cloned animal might be influenced by nuclear transfer technique itself and passages of donor cells as well as the activation methods of oocytes. We reconstructed oocytes with outbreeding Kunming albino mouse ES cells and enucleated rabbit oocytes, and analyzed the effects of the passages of ES cells and 6-DMAP on the development of interspecific reconstructed oocytes. The interspecific reconstructed ES-rabbit oocytes were activated either by combined two set electric pulses and 6-DMAP or by two set electric pulses alone. The rate of cleavage was significantly higher for the group (86.2%) treated with 6-DMAP than the group (64.2%, P < 0.05) treated with electric pulses only, and the rate of blastocysts was 17.0% and 13.4% respectively, which were not significantly different between two groups. When ES cells that had been passed for 24 and 14 generations were used as donors, the cleavage rates of the reconstructed oocytes were 88.5% and 82.1%, respectively (P > 0.05), and the rates of blastolation were 16.7% and 15.4%, respectively (P > 0.05). The results show that 6-DMAP increases the cleavage rate of reconstructed oocytes derived from ES cells, and affects slightly the developmental rate of blastocysts. There are no differences when high passage and low passage ES cells are used as nuclear donors.     

无花果叶共生菌发酵的菌种富集及抑菌活性的筛选

目的从无花果叶中分离和筛选能发酵分解无花果叶及具有抑菌作用的共生菌。方法采用以无花果叶作为唯一碳源的富集培养方法,分离共生菌并分析发酵菌群的构成。同时,通过研磨法直接分离无花果叶内生菌,对分离菌株进行分子生物学鉴定,利用平板滤纸片法进行菌株的抑菌活性分析。结果无花果叶发酵菌群由11种22株细菌构成,其中优势菌为短波单胞菌(Brevundimonas naejangsanensis)、嗜温鞘氨醇杆菌(Sphingobacterium thalpophilum)和副球菌(Paracoccus sp.)。没有获得发酵无花果叶的真菌菌群,只分离出1株产黄青霉菌(Penicillium chrysogenum)。直接分离共获得无花果叶内生细菌8种14株和内生真菌3种9株。抑菌试验表明,来源于富集培养的泡囊短波单胞菌(Brevundimonas vesicularis)和产黄青霉菌以及来源于内生菌的枯草芽胞杆菌(Bacillus subtilis)对枯草芽胞杆菌、大肠埃希菌和金黄色葡萄球菌3种指示菌有不同的抑菌作用,且它们的抑菌谱各不相同。泡囊短波单胞菌只在无花果叶中培养时才表现出抑菌活性。结论短波单胞菌可能与无花果叶的发酵分解有关,泡囊短波单胞菌与无花果叶之间发生了相互作用,因此,这2株菌可以作为无花果叶发酵的候选菌种应用。     

川西亚高山不同海拔森林土壤活性氮库及净氮矿化的季节动态

研究了川西理县毕棚沟不同海拔梯度(3600 m、3300 m和3000 m)森林群落土壤活性氮库及土壤净氮矿化速率的季节动态.结果表明: 研究区森林土壤活性氮库(铵态氮、硝态氮、微生物生物量氮和可溶性有机氮)及净氮矿化速率存在明显的季节变化,但不同形态土壤活性氮库的季节动态有一定差异.4个采样时期(非生长季与生长季初期、中期及末期)各海拔土壤硝态氮浓度(8.38～89.60 mg·kg^-1)均显著高于铵态氮浓度(0.44～8.43 mg·kg^-1).生长季初期各海拔梯度的土壤净氮矿化速率均表现为负值(-0.77～-0.56 mg·kg^-1·d^-1),而非生长季、生长季中期和末期均为正值.除硝态氮外,不同海拔的土壤铵态氮、微生物生物量氮和可溶性有机氮浓度的差异极显著,海拔对它们的影响与季节变化有关.该区土壤净氮矿化以硝化为主,且氮矿化过程不受海拔梯度的影响.冬季土壤净氮矿化明显(0.42～099 mg·kg^-1·d^-1),早春高的土壤无机氮可能为植物生长提供基础养分,也可能通过淋溶方式从系统中丢失.     

Production and selected fuel properties of biodiesel from promising non-edible oils: Euphorbia lathyris L., Sapium sebiferum L. and Jatropha curcas L

A comparative study on the composition, biodiesel production and fuel properties of non-edible oils from Euphorbia lathyris L. (EL), Sapium sebiferum L. (SS), and Jatropha curcas L. (JC) was conducted. Under optimal conditions, the FAME content and yield of the three oils were greater than 97.5 wt.% and 84.0%, respectively. The best biodiesel was produced from EL due to its high monounsaturation (82.66 wt.%, Cn: 1), low polyunsaturation (6.49 wt.%, Cn: 2, 3) and appropriate proportion of saturated components (8.78 wt.%, Cn: 0). Namely, EL biodiesel possessed a cetane number of 59.6, an oxidation stability of 10.4 h and a cold filter plug point of -11 °C. However, the cetane number (40.2) and oxidative stability (0.8 h) of dewaxed SS kernel oil (DSSK) biodiesel were low due to the high polyunsaturation (72.79 wt.%). In general, the results suggest that E. lathyris L. is a promising species for biodiesel feedstock.     

大鲵蛙病毒编码96L蛋白(ADRV-96L)的腺苷三磷酸酶活性和促进细胞生长作用

【背景】腺苷三磷酸酶(ATPase,ATP酶)是控制DNA复制起始及宿主对病原微生物的应答开关。近期关于水生动物虹彩病毒基因组学的研究表明,它们共享编码ATPase的基因。【目的】大鲵蛙病毒(Andrias davidianus ranavirus,ADRV)属于虹彩病毒科,是世界现存最大两栖动物——中国大鲵的致死性病毒病原体。为了鉴定病毒基因及其表达产物对病毒复制和宿主细胞的影响,对ADRV编码ATPase的基因ADRV-96L进行了克隆、表达及功能分析,阐明这个虹彩病毒核心基因的功能。【方法】采用Predic Protein软件分析序列,构建重组原核表达质粒p ET32a/His ADRV-96L,经IPTG(Isopropylβ-D-1-thiogalactopyranoside)诱导在大肠杆菌DE3中表达蛋白,用镍树脂纯化和咪唑液洗脱。钼蓝分光光度法检测产生的无机磷(Pi)以确定纯化ADRV-96L的ATPase活性。建立表达蛋白的稳定转染细胞系并进行鉴定,再分别通过绘制病毒的一步生长曲线和评估转染细胞的生长速率来测定该蛋白对病毒复制及细胞生长的影响。【结果】多重序列比对显示ADRV-96L存在含Walker A和Walker B基序的AAA-ATPase(ATPases associated with a variety of cellular activities,与各种细胞活性相关的ATPase)结构域(20-159位氨基酸)及两个高度保守的精氨酸。重组原核质粒表达了含ADRV-96L的52 k D融合蛋白,该蛋白质具有ATPase活性(酶的比活性平均为4.68 U/mg)。结果未检出ADRV-96L对病毒的复制影响,但显示该蛋白可促细胞生长。【结论】大鲵蛙病毒96L基因(ADRV-96L)编码一个促细胞增殖和生长的ATPase。     

基于固态基底的SERS免疫检测新方法研究

目的:通过引入新型表面增强拉曼散射(SERS)检测探针(Au-DTNB-Tyr NPs)和金标银染技术,建立基于固态硅片基底的SERS免疫检测新技术。方法:羊抗人IgM-HRP作为检测抗体,在硅片基底上检测不同浓度的人IgM,HRP催化SERS检测探针沉积,利用金标银染技术增强SERS信号。结果:所建立的SERS免疫检测新方法检测人IgM的检测限为10 pg/mL,且SERS信号强度与人IgM浓度具有良好的线性关系(R2=0.993)。结论:基于硅片基底的SERS免疫检测新技术可高灵敏地定量检测人IgM,为实现固态硅片基底对多种抗原的高通量集成化检测奠定了基础。     

Genetic and alkaloid analysis of Menispermum dauricum DC. by RAPD and HPLC

The aim of the present work was to determine whether dauricine could be used as a taxonomic marker for Menispermum dauricum DC., and to explore the correlation among RAPD, ecological markers and chemical markers. To this end, the chemical and genetic differences of 173 individual samples of M. dauricum from nine different sources were studied based on the relevant ecological factors including longitude, latitude, annual precipitation, mean temperature, annual accumulated temperature and mean sea level. The contents of dauricine in the sample rhizomes were assayed by HPLC with photodiode array detection. The leaves from the same sample were assayed using randomly amplified polymorphism DNA (RAPD). The genetic distances were then compared. Hierarchical cluster analysis and multiple linear stepwise regression analysis were used in the statistical analysis. The results indicated that the contents of dauricine were respectively correlated with the genetic distance (r = 1.000), longitude (r = 0.849), latitude (r = 0.861), annual precipitation (r = 0.903), mean temperature(r = 0.912), annual accumulated temperature (r = 0.919) and mean sea level (r = 0.925). It is concluded that the content of dauricine in M. dauricum is significantly correlated with genetic distance and ecological factors, and may be used as the taxonomic marker.     

球囊菌胁迫中华蜜蜂幼虫肠道过程中病原的转录组学研究

【目的】本研究利用RNA-seq技术对球囊菌胁迫的中华蜜蜂(中蜂)幼虫肠道进行深度测序,经趋势分析得到差异表达基因(DEGs)的显著表达模式,进而对胁迫过程中的球囊菌进行转录组学分析。【方法】利用Illumina HiSeq 2500平台对球囊菌胁迫的中蜂幼虫肠道进行深度测序,并利用相关软件进行了深入分析。最后,通过RT-qPCR对RNA-seq数据进行了验证。【结果】本研究共得到球囊菌的41133932条高质量clean reads。22865个DEGs共聚类为8个基因表达模式,其中,16769个DEGs聚类为2个显著上调趋势与2个显著下调趋势。GO富集分析结果显示,显著上调与显著下调趋势中的DEGs分别富集于40与37个GO term,基因富集数最多的为细胞进程(2486 unigenes)。KEGG代谢通路(pathway)富集分析结果显示,显著上调与显著下调趋势中的DEGs分别富集于119和112个pathway,基因富集数最多的分别是氨基酸生物合成(127 unigenes)与核糖体(98 unigenes)。进一步分析表明球囊菌在胁迫中蜂幼虫肠道的过程中通过提高物质合成促进其增殖,而宿主通过抑制球囊菌的蛋白合成抵御病原入侵。富集在MAPK信号通路的11个DEGs的表达水平随着胁迫时间的延长而逐渐下降,推测中蜂幼虫通过抑制该通路而阻遏球囊菌增殖。【结论】本研究不仅为揭示白垩病过程中的球囊菌-中蜂幼虫互作提供了重要信息,也为阐明不同抗性蜂种的球囊菌抗性差异奠定了基础。     

藏猪小肠形态、消化酶及微生物多样性研究

[目的]肠道是动物的主要消化器官,同时也是机体抵抗外源病原菌的重要屏障,已有研究表明,动物的品种、饲养方式、生长阶段均会影响动物的肠道菌群结构,但对舍饲和放牧饲养条件下藏猪的肠道菌群结构,以及藏猪和长白、约克与杜洛克三元杂交猪(DLY猪)的肠道菌群结构是否有差异,尚未见报道.[方法]本研究选取6-7月龄的放牧藏猪、舍饲...