狂犬病毒核蛋白（NP）的纯化及其免疫原性的研究

对重组痘苗毒和重杆状病毒表达的狂犬病毒NP及原代地鼠肾细胞培养的狂犬病毒核衣壳蛋白（RNP）、先经Sepharose CL 4B分子筛柱初步提纯,再经抗狂犬病毒NP McAB 2C12-S-epharose 4B亲和层析柱纯化分离,经ELISA、SDS－PAGE电泳和Western-Blot分析证实,获得了高纯度和免疫反应性的NP和RNP。以相同剂量的纯化蛋白免疫小鼠,RNP和两种重组NP均可诱生特异的抗NP抗体,三种蛋白间无明显差异;狂犬病毒CVS株攻击保护实验结果显示,三种蛋白免疫的小鼠存活率约为50％;两种重组NP的免疫反应性和免疫原性与天然狂犬病毒RNP相似。     

Theoretical electrical conductivity of hydrogen-bonded benzamide-derived molecules and single DNA bases

A benzamide molecule is used as a “reader” molecule to form hydrogen bonds with five single DNA bases, i.e., four normal single DNA bases A,T,C,G and one for 5methylC. The whole molecule is then attached to the gold surface so that a meta-molecule junction is formed. We calculate the transmission function and conductance for the five metal–molecule systems, with the implementation of density functional theory-based non-equilibrium Green function method. Our results show that each DNA base exhibits a unique conductance and most of them are on the pS level. The distinguishable conductance of each DNA base provides a way for the fast sequencing of DNA. We also investigate the dependence of conductivity of such a metal–molecule system on the hydrogen bond length between the “reader” molecule and DNA base, which shows that conductance follows an exponential decay as the hydrogen bond length increases, i.e., the conductivity is highly sensitive to the change in hydrogen bond length.     

精子载体法制备转基因动物的研究进展

精子载体法是一种低成本、简单快速制备转基因动物的方法.外源基因主要通过两种方式实现基因整合,一种是直接整合到精子的基因组中;另一种是通过精子携带进入卵细胞,然后整合到受精卵的基因组中.尽管现在已经有很多利用精子载体法获得了转基因动物的研究,但是基于精子在受精过程中,结合、内化、以及转运外源基因等方面能力的差异,转染效率仍有待提高.就利用精子载体法制备转基因动物过程中,精子载体法制备转基因动物的分子机制和方法方面进行系统的阐述和分析.     

Delayed development of the whitefly (Bemisia tabaci) and increased parasitism by Encarsia bimaculata in response to sublethal doses of piperonyl butoxide

Abstract Effects of sublethal piperonyl butoxide (PB) on parasitization of Bemisia tabaci (Gennadius ) (Hemiptera: Aleyrodidae) by Encarsia bimaculata Heraty et Polaszek (Hymenoptera: Aphelinidae) were evaluated both in cage and greenhouse experiments. When first, second and third instar B. tabaci nymphs were treated with PB, all but the first instar were significantly prolonged. Data indicated that sublethal PB could improve E. bimaculata parasitism rates without influencing parasitoid eclosion rates. Prolonged development increased rates of parasitism by E. bimaculata, from 17.6% to 24.7% in cages, presumably by increasing the duration of host exposure. Sublethal PB combined with E. bimaculata as an integrated approach to control B. tabaci was evaluated using life table parameters under greenhouse conditions. Indices of population trend (I) calculated from life tables were estimated at 4.6 for B. tabaci exposed to PB and parasitoids compared to 14.1 with parasitoids alone and 23.5 in untreated controls. The results showed that after PB was sprayed and parasitoids introduced, development of B. tabaci was delayed and the peak of each stage was postponed. The older nymphal stage had highest mortality, primarily due to mortality caused by parasitism by E. bimaculata.     

山羊品种间体细胞核移植研究

萨能奶山羊是著名的奶用山羊品种,波尔山羊则是世界著名的肉用山羊品种.为了研究波尔山羊体细胞在奶山羊卵母细胞中的去分化,我们将成年波尔山羊的颗粒细胞或耳皮肤成纤维细胞作为供核细胞(试验组),移入奶山羊中Ⅱ期的去核卵母细胞透明带下,经电融合和离子霉素与6-二甲基氨基嘌呤(6-DMAP)激活,直接移入同期发情奶山羊输卵管或经体内培养,将发育的重构胚移人同期发情羊子宫内.妊娠早期作B超诊断,确立妊娠的观察至足月.同时将奶山羊的35日龄胎儿成纤维细胞作供核细胞(对照组),按试验组同样方法处理,将重构胚直接移入同期发情的奶山羊输卵管内.结果试验组,波尔羊颗粒粒细胞与耳皮肤成纤维细胞的融合率分别为78.2%(115/147)、57.4%(116/202),重构胚卵裂率为85.8%(115/134),桑椹胚、囊胚的发育率38.8%(52/134),早期妊娠三头,分别于妊娠40、60、60日龄终止妊娠.对照组,融合率为89.5%(136/152),早期妊娠率为42.9%(6/14),四头受体足月分娩,产四头公羊羔,其中三头存活,一头分娩时死于肺不扩张,并体重过大,显示胎儿过大综合症.经基因型鉴定证实,这四头克隆羔羊均源于同一胎儿成纤维细胞系.以上结果表明,波尔羊体细胞核在奶山羊卵母细胞中能够去分化,并维持一定程度的发育.     

Elevated Serum and Cerebrospinal Fluid Free Fatty Acid Levels Are Associated with Unfavorable Functional Outcome in Subjects with Acute Ischemic Stroke

The aim of this study was to evaluate the prognostic value of serum and cerebrospinal fluid (CSF) free fatty acid (FFA) levels in a cohort of patients with an acute ischemic stroke (AIS). In a prospective study, FFA levels were measured using an enzyme cycling method on admission in serum and CSF of 252 consecutive patients with AIS. The prognostic value of FFA to predict the functional outcome and mortality within 90-day was compared with the National Institutes of Health Stroke Scale score and with other known outcome predictors. Serum and CSF levels of FFA increased with increasing severity of stroke as defined by the NIHSS score (all P?<?0.001). Patients with an unfavorable outcomes and non-survivors had significantly increased FFA serum and CSF levels on admission (all P?<?0.0001). Multivariate logistic regression analysis adjusted for common risk factors showed that serum FFA ≥0.71 mmol/L (third quarters) was an independent predictor of functional outcome (odds ratios (OR)?=?4.86; 95 % confidence interval (CI) 2.26–10.48) and mortality (OR?=?7.72; 95 % CI 3.01–21.48). The area under the receiver operating characteristic curve of serum FFA was 0.79 (95 % CI, 0.72–0.86) for functional outcome and 0.86 (95 % CI, 0.78–0.94) for mortality. Similarly, CSF FFA level also was an indicator for predicting of functional outcome and mortality. FFA levels in serum and CSF may serve as independent biomarkers in addition of the traditional methods for assessing the functional outcome and mortality of AIS.     

突变级数法在厦门城市生态安全评价中的应用

针对港湾快速城市化地区存在的潜在突变特性,基于P-S-R(压力-状态-响应)框架和突变级数法,构建了评价城市生态安全的突变模型,并对1996—2006年厦门城市生态安全进行了评价.结果表明：1996—1998年,快速城市化对厦门市区域生态安全的影响不大,研究区生态安全状况呈上升趋势;1998—2001年,由于大范围高强度的填海造地、人口激增等生态干扰远远超过了生态系统自身的修复能力,导致厦门城市生态安全状况呈快速下降趋势;2001—2006年,厦门城市生态安全整体水平回升,主要受其海湾型生态城市重大战略转变的影响;2006年,研究区系统压力安全级别为Ⅲ,说明厦门市还存在着生态安全隐患.突变级数法反映了单一指标极值情况对生态系统突变的影响,弥补了现有方法在此方面的不足,它既减小了权重赋值的主观性,又避免了主观判断安全标准的不确定性,可准确地反映城市生态安全的发展趋势.     

“两广二号”家蚕抗病毒基因Bmlipase-1和BmSP-2克隆与原核表达

本研究以优良杂交品种"两广二号"家蚕为试材,克隆了该杂交品种家蚕两个抗家蚕核型多角体病毒(BmNPV)基因:脂肪酶基因Bmlipase-1和丝氨酸蛋白酶基因BmSP-2,测序并分别与不同品种蚕的同源基因序列进行比较。结果显示,"两广二号"家蚕Bmlipase-1基因ORF长度为885bp,编码294个氨基酸,BmSP-2扩增长度为855bp,编码284个氨基酸;它们的核苷酸和推导氨基酸序列同源性皆达92%以上,Bmlipase-1更保守,同源性大于99%";两广二号"家蚕的Bmlipase-1基因脂肪酶活化部位和BmSP-2基因酶催化三联体位点的氨基酸残基与不同品种蚕的完全相同。以上结果说明这两个抗病毒基因在蚕的遗传进化过程中高度保守,提示其可能在机体消化或者免疫防御方面起着重要生理作用。将这两个抗病毒基因在大肠杆菌BL21中进行融合表达,获得的融合Bmlipase-1和BmSP-2蛋白分子量分别为47kD和42kD左右。