不同配置模式林分中光肩星天牛空间格局的地统计研究

运用地统计学方法对光肩星天牛在新疆杨和复叶槭混交林（新复混交林）、合作杨纯林以及新疆杨与合作杨混交林（新合混交林）3种林分中的空间格局进行了研究.结果表明：刻槽、排粪孔和羽化孔在新复混交林和合作杨纯林中呈现较明显的空间聚集状态,而在新合混交林中则呈现完全的随机分布.新复混交林中,刻槽和排粪孔在林内的扩散趋势完全相反,即刻槽由林地周围向中心扩散,而排粪孔则由林地中心向四周扩散,这在一定程度上反映了光肩星天牛喜好产卵于刻槽较少,危害较轻的树上,而羽化孔在新复混交林中的分布数量较少,仅有几处聚集分布,由这些零星分布的聚集斑块向周围扩散;合作杨纯林中,由于林缘通风透光,合作杨生长状况较好,受害严重,从而导致枯死,最终失去对光肩星天牛的诱集作用,光肩星天牛刻槽、排粪孔和羽化孔由林地周围向中心扩散;而新合混交林中,刻槽、排粪孔和羽化孔在林内有多个聚集区域,并以此为中心向四周扩散,保持聚集和扩散平衡状态,从而表现为随机分布,这主要是由林内树种的配置情况所决定的.就不同配置树种的空间依赖性范围而言,刻槽和羽化孔在新复混交林内的空间依赖性范围要远远大于合作杨纯林,而排粪孔则远小于合作杨;就样方内的空间连续性强度而言,新复混交林中刻槽大于合作杨纯林,而排粪孔和羽化孔均小于合作杨纯林,这些均说明光肩星天牛危害在新复混交林内较集中,而在合作杨纯林内较分散.     

传染性法氏囊病病毒VP3抗原表位的鉴定

利用肽扫描技术对4株IBDV VP3的单克隆抗体(HRB-3F、HRB-7B、HRB-7C和HRB-10E)的抗原表位进行了研究.通过Western blot和ELISA鉴定,将HRB-3F和HRB-7B的抗原表位定位于VP3 109～119 aa(位于IB-DV聚合蛋白的864～874 aa),HRB-7C和HRB-10E的抗原表位定位于VP3 177～190 aa(位于IBDV聚合蛋白的932～945 aa).进一步检测其反应原性及免疫原性,结果表明,这两个表位均能与抗IBDV阳性血清反应.将这两个表位短肽免疫BALB/c小鼠,其血清可以和IBDV反应,具有较好的免疫原性.与D6948、HK46和UK661等多株IBDV相应区域的同源性进行了比较,结果显示,这两个表位在多种毒株中同源性为100%.通过IBDV VP3抗原表位的研究,筛出两个新的保守线性表位并进行精确定位,对进一步分析IBDV结构与功能以及建立以表位为基础的抗原抗体诊断方法具有重要的意义.     

禽呼肠孤病毒σC基因在杆状病毒表达系统中的表达及其活性鉴定

本研究利用Bac-To-Bac杆状病毒表达系统构建重组禽呼肠孤病毒(Avian reovirus,ARV)σC基因的杆状病毒,感染sf9细胞获得表达重组蛋白。首先,将ARVσC基因克隆至pFastBacHTA载体,构建重组供体载体pFσC,将其转化大肠杆菌DHl0Bac感受态细胞,使σC基因整合到Bacmid穿梭载体中,获得重组穿梭载体BacmidσC。通过脂质体介导将其转染到sf9昆虫细胞中,获得重组杆状病毒rBacσC。通过Western Blot、间接免疫荧光试验(IFA)进行检测,结果显示:σC蛋白在重组杆状病毒rBacσC感染的sf9昆虫细胞中获得正确表达,分子质量约为37kD,表达的σC蛋白具有良好的反应活性。     

在生长、功能和萎退各期,大鼠乳腺磷酸酶的研究

前言虽然乳腺在生长、功能和萎退过程中形态上的变化是很大的(姚曾序、顾国彦,1957),可是和形态变化相伴随的化学和生物化学变化却研究得少。关于碱性磷酸酶(以下简称 AKP)方面,Kay(1925),Folley 和 Kay(1935)最早证明牛、羊和豚鼠乳腺含有相当量的这种酶。以后 Folley 和 Greenbaum(1947)进一步用生化方法研究了大鼠在怀     

传染性法氏囊病病毒的自然重组

传染性法氏囊病病毒(Infectious Bursal Disease Virus,IBDV)是双RNA病毒科(Birnaviridae)的典型代表,其引起的传染性法氏囊病(Infectious Bursal Disease,IBD)是危害养禽业的一种重要免疫抑制病和致死性传染病。IBDV的自然重组给疫病防控带来了新风险。本文综述了IBDV基因组节段重组和基因内重组的主要类型,分析了其形成机制及生物学意义,提出了该类病毒遗传演化研究以及疫病综合防控的新思路。     

内蒙古乌达煤田早二叠世太原组拥挤始莲座蕨(新种) Eoangiopteris congestus sp. nov.

本文报道发现于内蒙古乌达煤田早二叠世太原组顶部火山凝灰岩层中的莲座蕨类植物一新种Eoangiopteris congestus sp. nov.,标本包含有机连生的辉木型茎干,栉羊齿型营养羽片和始莲座蕨型繁殖羽片。其中营养羽片为三次羽状复叶,末二次和末次羽片均为线形,小羽片栉羊齿型,卵圆形,中脉下延,侧脉分叉一次,属于东方栉羊齿Pecopteris orientalis (Schenk) Potonié类型。繁殖小羽片与营养小羽片同形;两侧对称的聚合囊成单列分布在中脉两侧,排列拥挤,由6–8个孢子囊组成,通过一个薄壁组织构成的聚合囊托与叶片相连;孢子囊呈纺锤形,无环带;孢子囊面向外的壁2–3层细胞厚,面向内的壁厚度仅1层细胞。原位孢子为三缝孢,椭圆形至圆形,表面具小刺状纹饰,可与分散孢子属Apiculatisporites对比。当前始莲座蕨属植物的发现代表其在华夏植物群目前最早的化石记录。此外,这些两侧对称的聚合囊明显区别于以往报道中与东方栉羊齿叶型化石连生的辐射对称聚合囊类型(星囊蕨Asterotheca),表明在古植物学研究中一种化石羽片类型可能对应多种繁殖器官类型。     

Claudins and ki-67: potential markers to differentiate low- and high-grade transitional cell carcinomas of the urinary bladder

Updated classification of urothelial cell cancer differentiates low-grade and high-grade cancers, which determines potential clinical outcome. Substantial interobserver variability necessitates new biomarkers to ensure classification. Claudins' specific expression pattern characterizes normal tissues, different tumor types, and defined grades of tumor differentiation. The aim of this study was to examine the expression pattern of claudins and proliferation marker Ki-67 in low-grade and high-grade urothelial cell cancers compared with independent control samples of non-tumorous urothelium, as well as to reveal the predictive usefulness of claudins. The expression of claudins-1, -2, -3, -4, -5, -7, and -10 and Ki-67 was studied with quantitative immunohistochemistry and real-time RT-PCR with relative quantification in 103 samples: 86 urothelial cell cancers (27 low grade, 59 high grade) and 17 non-tumorous urothelia. Results were analyzed regarding overall survival and recurrence-free period as well. High-grade tumors overall showed significantly higher claudin-4 and Ki-67 and significantly lower claudin-7 expression when compared with low-grade ones. High-grade tumors revealed significantly shorter overall survival in Kaplan-Meier analysis. Claudin-4, claudin-7, and Ki-67 might be used as potential markers to differentiate low-grade and high-grade urothelial cell cancers, thereby possibly enhancing accuracy of pathological diagnosis and adding further information to clinical outcome.     

Mature N-linked glycans facilitate UT-A1 urea transporter lipid raft compartmentalization

The UT-A1 urea transporter is a glycoprotein with two different glycosylated forms of 97 and 117 kDa. In this study, we found the 117-kDa UT-A1 preferentially resides in lipid rafts, suggesting that the glycosylation status may interfere with UT-A1 lipid raft trafficking. This was confirmed by a site-directed mutagenesis study in MDCK cells. The nonglycosylated UT-A1 showed reduced localization in lipid rafts. By using sugar-specific binding lectins, we further found that the UT-A1 in nonlipid rafts contained a high amount of mannose, as detected by concanavalin A, while the UT-A1 in lipid rafts was the mature N-acetylglucosamine-containing form, as detected by wheat germ agglutinin. In the inner medulla (IM) of diabetic rats, the more abundant 117-kDa UT-A1 in lipid rafts was the mature glycosylation form, with high amounts of N-acetylglucosamine and sialic acid. In contrast, in the IM of normal rats, the predominant 97-kDa UT-A1 was the form enriched in mannose. Functionally, inhibition of glycosylation by tunicamycin or elimination of the glycosylation sites by mutation significantly reduced UT-A1 activity in oocytes. Taken together, our study reveals a new role of N-linked glycosylation in regulating UT-A1 activity by promoting UT-A1 trafficking into membrane lipid raft subdomains.