High efficient expression of human endostatin in E.coli and its antiangiogensis activity

AIM: To examine the expression of human endostatin in E.coli, produce its fusion protein antibody and observe its biological activity. METHODS: Endostatin gene was amplified by polymerase chain reaction,recombined with plasmid vector pGEX-2T and induced expression with IPTG.The protein activity was tested by endothelial cell proliferation inhibitory assay.Inclusion body crudely purified was used to generate polyclonal antibody to detect its expression at mouse's liver and kidney etc. RESULTS: The protein expressed was 20kD after digestion by thrombin,it appeared the anti-angiogenesis activity and Western blotting indicated the expression of endostatin in liver and kidney of mouse. CONCLUSION: The successful expression of human endostatin and the preparation of polycolonal antibody indicated its potential application in anti-angiogenesis therapy and diagnosis tumors.     

不同引物对植原体的检测灵敏度比较研究

用常规PCR和巢式PCR对目前常用的各种植原体引物(fPl/rP7、fU5/rP7、fU5／rU3、fAY/rEY和fFD9/rFD9)的检测灵敏度进行了比较研究。研究发现，它们的检测灵敏度并不相同。最灵敏的引物(fAY/rEY)要比最不灵敏的引物(fFD9/rFD9)的灵敏度至少高出数千倍。因此，按照不同的检测目的选择所用的检测引物是明智的，特别是当待测样品中的植原体浓度极低时，比如葡萄组织样品中植原体的检测。据此提出了用于不同检测目的时的最佳引物。     

琯溪蜜柚光合特性的研究

 利用Li-6400 光合作用仪对田间条件下7 年生琯溪蜜柚的光合特性进行了系统研究。结果表明: (1) 琯溪蜜柚外围叶片晴天的净光合速率(P_n) 日变化为双峰曲线, 首峰出现在8～10 时, 次峰值小于首峰值, 出现在14 时以后; 阴天呈单峰曲线; 内膛叶片P_n 日变化有双峰、单峰和锯齿形3 种类型。(2)观测期内P_n季节变化近似双峰曲线。(3) 不同月份和不同枝条叶片Pn 对光和CO₂ 响应有较大差别, 光补偿点和饱和点分别为16～46 和1 026～1 656μmol·m^-2·s^-1 , 表观量子效率0.01725～0.05431 ; CO₂ 补偿点和饱和点分别为51～80 和822～926μmol·mol ^-1 , 羧化效率0.01769～0.05191 ;P_n对CO₂ 的响应进程近似双曲线。(4) P_n与气孔导度、蒸腾速率、光照强度正相关, 与胞间CO₂ 浓度负相关, 与温度、湿度和叶面水气压亏缺的相关性比较复杂。(5) P_n 与叶片的叶绿素含量和比叶重之间没有明显相关性。(6) 光合适温为24～34 ℃。     

Variability amongst strains of Fusarium poae assessed by vegetative compatibility and RAPD polymorphism

Vegetative compatibility tests and random amplification of polymorphic DNA (RAPD) were used to assess genetic relationships amongst 54 strains of Fusarium poae obtained from various geographical regions. Twenty-seven strains were assigned to eight multiple member vegetative compatibility groups (VCGs), while the other 27 isolates were found to form single-member VCGs. There was a partial correlation between VCG and geographical origin, but the relationship was not always clear. However, no correlation was observed between the VCG and the host plant of origin. RAPD patterns were closely associated with VCGs in all cases. Members of VCGs that were interconnected by bridging isolates formed common branches in the phenogram constructed on the basis of the RAPD patterns, while strains that belonged to single-member VCGs were scattered throughout the phenogram. These data demonstrate that the combination of traditional and molecular methodologies allows reliable intraspecific subdivisions in an asexual fungus, which is a secondary invader of a wide range of host plants, and so has never been subject to the intense selection pressure of a single host species and lacks pathogenic subgroups.     

Biological control in Hungary: present situation and possibilities1

Biological control has already achieved certain results in Hungary, especially against soil-borne fungi and glasshouse pests. Nevertheless, experience has shown that locally found biological agents, however effective, could not be developed into registered, ready-for-sale plant protection products because of the lack of companies willing to invest. Biological control in Hungary is therefore limited to the conservation of natural antagonistic flora and fauna and to the application of imported biopesticides and bioagents, which are subject in Hungary to a registration procedure similar to that for chemical plant protection products. Current work includes the development of an anti-nematode product from a local strain of Arthrobotrys oligospora, application techniques for a local mirid Dicyphus hyalinipennis against insect pests, studies with native and imported strains of the nematodes Steinernema and Heterorhabditis against soil-borne insect pests, and introduction techniques for the chrysomelid Zygogramma sutularis against the weed Ambrosia elatior.     

长期施肥条件下菜田—蔬菜生态系统变化的研究( Ⅳ) 蔬菜生态系统的变化

 以2002 年设施番茄栽培为代表计算其N、P、K投入量与携出量之间的表观平衡状态, 其结果基本上和14.5 年后的土壤实测值与设施栽培本底值之间纵向比较的增长关系一致, 前者只能说明系统养分变化的趋势, 后者才是实际的养分盈亏状态, 养分盈亏主要取决于有机肥的施用与养分元素的供给。5个代表性处理模拟了蔬菜施肥的不同现状, 从土壤肥力及产量等方面的变化真实反映出各自的系统变化及发展趋势, 在本试验条件下以ANK施肥下的系统最优。对有机肥施用、化学肥料的配施以及测土施肥等问题进行了探讨。     

Visualization of the effect of a surfactant on the uptake of xenobiotics into plant foliage by confocal laser scanning microscopy

A radiolabelling method is generally used to determine the foliar uptake of xenobiotics. This technique cannot provide any information on the localization of chemicals inside leaf tissues. The influence of an alcohol ethoxylate surfactant on the uptake of three fluorescent dyes, difluorofluorescein (hydrophilic), rhodamine B (moderately lipophilic) and a naphthalimide dye (lipophilic), into the leaves of three contrasting species, bean (Vicia faba), wheat (Triticum aestivum) and cabbage (Brassica oleracea), at 16 h after treatment was measured using a conventional wash‐off method and also visualized in vivo by confocal laser scanning microscopy (CLSM). Whereas the lipophilic dyes showed greater intrinsic uptake than the hydrophilic one, the enhancing effect of the surfactant on uptake was more pronounced for the latter. CLSM revealed that the presence of the surfactant increased the transport of difluorofluorescein into the epidermal cells of bean and wheat leaves, but not cabbage leaves. Rhodamine B showed greatest transcuticular diffusion in all three species, but most of the dye moved into the vacuole of the epidermal cells. The naphthalimide dye was strongly retained by the wax–cuticle layer of all species, even in the presence of the surfactant. CLSM has proven to be an attractive tool for studying xenobiotic diffusion. The results obtained using fluorescent dyes are believed to be applicable to the foliar uptake of herbicides.     

Effectiveness of the resistance inducer prohexadione‐Ca against fireblight in shoots of apple trees inoculated with Erwinia amylovora1

Due to the lack of effective, non‐phytotoxic and publicly acceptable materials for controlling fireblight in pome fruit trees, novel strategies against Erwinia amylovora are being sought. Resistance‐inducing compounds, such as prohexadione‐Ca, represent promising alternatives. Prohexadione‐Ca is the active substance of the bioregulator Regalis, currently being introduced in several European countries and overseas. Prohexadione‐Ca reduces shoot elongation due to inhibition of gibberellin biosynthesis. Furthermore, it leads to significant changes in the spectrum of flavonoids and their phenolic precursors in pome fruits, which causes reduced susceptibility to fireblight and other pathogens. In 2002 and 2003, container‐grown apple trees of the cultivars ‘Idared’ and ‘Freedom’ were treated with different dosages of prohexadione‐Ca two weeks before inoculation with E. amylovora. The effect of prohexadione‐Ca against shoot blight was determined by measuring the lengths of necrotic lesions and symptoms on vascular bundles caused by the pathogen. Treatments with prohexadione‐Ca turned out to be much superior to the ones with streptomycin, kasugamycin and a bacterial antagonist, which were used for comparison. Acibenzolar‐S‐methyl (Bion), another resistance‐inducing compound, was included in some of the experiments and gave intermediate results. The simultaneous control of excessive shoot growth and shoot infections by fireblight is seen as a major advantage of using prohexadione‐Ca in pome fruit trees.     

Long-term study (2005–2010) on the vaccination with BoHV-1 glycoprotein E-deleted marker vaccine in selected two dairy herds in Turkey

A follow-up study from 2005 to 2010 was carried out in two herds where eradication programme for the bovine herpes virus-1 (BoHV-1) infection depends on the vaccination with inactivated glycoprotein E-deleted vaccine that was started in 2001 following the vaccination with inactivated conventional vaccine between 1999 and 2001. For serological screening, a total of 12,976 sera sampled over several sampling times approximately 6 months of interval during 5 years (2005–2010) were tested for glycoprotein E (gE)- and glycoprotein B-specific antibodies using ELISA. According to the serological evidence, the long-term persistence of BoHV-1 antibodies, success of marker vaccine, first vaccination time of the calves in herds regularly vaccinated, etc. were discussed in this paper. In conclusion, the vaccination programme using gE (?) marker vaccines, with making efforts to prevent the other factors about transmission of infection, was suggested for the eradication of BoHV-1 infection in Turkey as many EU countries. This is the first report on the BoHV-1 eradication programme in some dairy cattle in Turkey.