乙型肝炎病人尿细胞中HBV的实验研究

本文采用间接免疫荧光法（ＩＦ）,ＲＰＨＡ法,ＥＬＩＳＡ法及斑点杂交技术检测１０例无症状ＨＢ－ｓＡｇ携带者及８９例乙肝病人尿细胞中的ＨＢｓＡｇ、ＨＢｅＡｇ及ＨＢＶＤＮＡ,发现尿细胞中有ＨＢｓＡｇ、ＨＢｅＡｇ、ＨＢＶＤＮＡ存在。结果提示：乙肝无症状携带者及乙肝病人尿细胞中具有ＨＢｓＡｇ、ＨＢｅＡｇ、ＨＢＶＤＮＡ,因此更进一步证实尿液具有传染性。     

浅谈转基因克隆动物技术

根据现有理论和技术发展趋势,提出了转基因克隆动物的概念,即将克隆动物与转基因克隆动物技术有机地结合起来,认为转基因克隆动物制作 技术将有望成为下一世纪创建遗传工程动物的主导性技术。     

利用雨生红球藻表达系统高通量筛选活力提高的阿特拉津氯水解酶突变子

阿特拉津氯水解酶定向改造的关键是开发一种廉价的、表型改变明显的高通量筛选方法。利用高错误倾向PCR和DNA洗牌相结合的突变方法,对来源于假单胞菌ADP和节杆菌AD1的阿特拉津氯水解酶基因进行随机突变,以雨生红球藻为受体、以阿特拉津为选择压力对突变文库进行高通量筛选。筛选到的12个突变子序列分析显示,突变均为点替换,位点分散在全基因上,是在高错误倾向PCR及DNA洗牌过程中逐渐累积形成的。酶活力分析显示,突变子的酶活力均高于野生株,在添加1.0 mg/L阿特拉津培养液中的活力是野生株的1.9~3.6倍,在添     

Meta‐barcoding insights into the spatial and temporal dietary patterns of the threatened Asian Great Bustard (Otis tarda dybowskii) with potential implications for diverging migratory strategies

Food resources are often not sufficient to satisfy the nutritional and energetic requirements during winter conditions at high latitudes. Dietary analysis is a prerequisite to fully understanding the feeding ecology of a species and the nature of trophic interactions. Previous dietary studies of Asian Great Bustard (Otis tarda dybowskii) relied on behavioral observations, resulting in categorization of diet limited to broad taxonomic groupings. Here, we applied a high‐throughput sequencing meta‐barcoding approach to quantify the diet of resident and migratory Asian Great Bustard in three wintering sites during early winter and late winter. We detected 57 unique plant taxa in the bustard diet, among which 15 species were confirmed by a local plant database we generated. Both agricultural and natural foods were detected, indicating a relatively broad dietary niche. Spatiotemporal dietary changes were discovered, revealing diet differences among wintering sites and a general shift toward lower plant diversity later in winter. For the nonmigratory population, we detected a significantly more diverse array of plant species in their diet. We hypothesize that dietary variation between resident and migratory populations could be involved in the recent transition to partial migration in this species, although climate change can not be excluded. Collectively, these results support protecting unharvested grain fields and naturally unplowed lands to help conserve and promote population growth of Asian Great Bustard.     

Behavioral and physiological responses of forest musk deer (<Emphasis Type="Italic">Moschus berezovskii</Emphasis>) to experimental fawn manipulation

High stress response is an important factor impeding the breeding of wild animals in captivity. Experimental fawn manipulation is considered a suitable approach to reduce the negative effects of behavioral and physiological stress. The forest musk deer (Moschus berezovskii) is classified as “endangered” by the IUCN Red List due to over-exploitation for musk production. Musk is highly valued for its cosmetic and alleged pharmaceutical properties and has stimulated the enthusiasm of captive musk deer breeding in recent years. This study attempts to reduce behavioral and physiological stress responses in juvenile musk deer using experimental fawn manipulation. Habituation started 5 days after birth and lasted until weaning age (90 days). We determined the behavioral stress response at the age of 30, 60, 90, 150, and 360 days by measuring acceptance or rejection of three treatment intensities (i.e., stroking, embracement) and quantified behavioral responses (urination, approaching the investigator). At the same time, physiological stress parameters were established, measuring the fecal glucocorticosteroid metabolite (FGM) concentration. Our results indicate that fawn manipulation initially reduced the behavioral stress, but after termination of treatments, stress symptoms reoccurred. We detected no difference in the FGM concentrations between treatment and control groups, suggesting that the experimental fawn manipulation did not decrease the physiological stress response. This implies that behavioral stress reduction cannot be sustained if the physiological stress remains unaltered. We argue that the socio-positive reactions of musk deer fawns to humans could be phenotypic and that the physiological stress response rather reflects their intrinsic characteristics than a successful manipulation.     

重组马铃薯X病毒注射番茄果实高效表达胸腺素a1

植物病毒载体表达外源蛋白表达水平高、表达速度快、宿主范围广。本研究用马铃薯X病毒(PVX)载体在番茄果实中表达胸腺素α1(Tα1),是一种快速高效生产医用蛋白的新方法。将pGEM-T-Easy-Tα1质粒酶切,获得大约100bp大小的Tα1基因片段,并将该片段与PVX载体(pGR-107)连接,用SalI和ClaI酶切鉴定,筛选出阳性重组体。进一步将重组质粒转化根癌农杆菌GV3101,用农杆菌注射法(Agroinjection)侵染不同生长阶段的番茄果实,用ELISA检测外源蛋白Tα1的表达水平。结果表明已成功构建了pGR107-Tα1表达载体,在农杆菌的菌液密度(OD600值)为1.0、番茄植株开花后2周半到3周时侵染番茄果实,Tα1的表达量最大。     

石油污染土壤的微生物治理研究进展

采用微生物治理土壤石油污染以效率高、成本低、无二次污染、易于管理等特点而受到重视,作为一种有效的治污手段具有广阔市场和发展前景。本文结合了国内外最新研究成果,对石油污染土壤微生物治理技术、影响因素、强化措施和最新发展进行了概述,以期综合全面反映该领域的研究概况,并对这一治理方法在我国的发展前景进行了展望。     

Transgenic tobacco plants expressing atzA exhibit resistance and strong ability to degrade atrazine

Atrazine chlorohydrolase (AtzA) catalyzes hydrolytic dechlorination and can be used in detoxification of atrazine, a herbicide widely employed in the control of broadleaf weeds. In this study, to investigate the potential use of transgenic tobacco plants for phytoremediation of atrazine, atzA genes from Pseudomonas sp. strain ADP and Arthrobacter strain AD1 were transferred into tobacco. Three and four transgenic lines, expressing atzA-ADP and atzA-AD1, respectively, were produced by Agrobacterium-mediated transformation. Molecular characterization including PCR, RT-PCR and Southern blot revealed that atzA was inserted into the tobacco genome and stably inherited by and expressed in the progenies. Seeds of the T₁ transgenic lines had a higher germination percentage and longer roots than the untransformed plants in the presence of 40–150 mg/l atrazine. The T₂ transgenic lines grew taller, gained more dry biomass, and had higher total chlorophyll content than the untransformed plants after growing in soil containing 1 or 2 mg/kg atrazine for 90 days. No atrazine residue remained in the soil in which the T₂ transgenic lines were grown (except 401), while, in the case of the untransformed plants, 0.91 mg (81.3%) and 1.66 mg (74.1%) of the atrazine still remained in the soil containing 1 and 2 mg/kg of atrazine, respectively, indicating that the transgenic lines could degrade atrazine effectively. The transgenic tobacco lines developed could be useful for phytoremediation of atrazine-contaminated soil and water.     

A preliminary study of trace elements in plasma protein by gel chromatography combined with SXRF

Fractions of plasma protein of male Kunming mice (body weight 24.2±0.3g), treated with Cisplatin i.p. injection in dose of 10mg/kg, were obtained by separation on Sephadex-G-50 columns, buffered with ammonium acetate to pH 5.7. The SXRF experiments were performed at the BEPC (Beijing Electron Positron Collider) synchrotron radiation facility. The elements (Pt, S, Ca, Fe, Ni, Cu, Zn, Se, Br and Sr) in the fraction of the plasma proteins (< 22KD) were assayed using highly sensitive SXRF. The relative concentrations of elements were calculated by a normalization of Compton scattering intensity around 22 keV, after the normalization for collecting time of X-ray spectrum and the counting of the ion chamber, and subtracting the contribution of the polycarbonate film used for supporting the samples. The determination could prove that the element Pt in plasma was bound with macro-molecularprotein. Cu and S were present in the fraction of the protein in mice treated with Cisplatin and exhibited an increase, the ratio of treated/control were 1.66±0.06 and 1.78±0.33 respectively, whereas Zn decreased to a ratio of 0.78±0.09. Our results are in agreement with others which showed that Cisplatin exposure leads to a marked loss of kidney copper, and a moderate rise in kidney zinc. However, this work mainly focussed on the implementation of this analytical procedure, but not on the results of the investigations of the effect of Cisplatin on trace elements in plasma protein.