Enhanced resistance to stripe rust disease in transgenic wheat expressing the rice chitinase gene RC24

Stripe rust is a devastating fungal disease of wheat worldwide which is primarily caused by Puccinia striiformis f. sp tritici. Transgenic wheat (Triticum aestivum L.) expressing rice class chitinase gene RC24 were developed by particle bombardment of immature embryos and tested for resistance to Puccinia striiformis f.sp tritici. under greenhouse and field conditions. Putative transformants were selected on kanamycin-containing media. Polymease chain reaction indicated that RC24 was transferred into 17 transformants obtained from bombardment of 1,684 immature embryos. Integration of RC24 was confirmed by Southern blot with a RC24-labeled probe and expression of RC24 was verified by RT-PCR. Nine transgenic T₁ lines exhibited enhanced resistance to stripe rust infection with lines XN8 and BF4 showing the highest level of resistance. Southern blot hybridization confirmed the stable inheritance of RC24 in transgenic T₁ plants. Resistance to stripe rust in transgenic T₂ and T₃ XN8 and BF4 plants was confirmed over two consecutive years in the field. Increased yield (27–36 %) was recorded for transgenic T₂ and T₃ XN8 and BF4 plants compared to controls. These results suggest that rice class I chitinase RC24 can be used to engineer stripe rust resistance in wheat.     

Novel inhibitors of bacterial virulence: Development of 5,6-dihydrobenzo[h]quinazolin-4(3H)-ones for the inhibition of group A streptococcal streptokinase expression

Resistance to antibiotics is an increasingly dire threat to human health that warrants the development of new modes of treating infection. We recently identified 1 (CCG-2979) as an inhibitor of the expression of streptokinase, a critical virulence factor in Group A Streptococcus that endows blood-borne bacteria with fibrinolytic capabilities. In this report, we describe the synthesis and biological evaluation of a series of novel 5,6-dihydrobenzo[h]quinazolin-4(3H)-one analogs of 1 undertaken with the goal of improving the modest potency of the lead. In addition to achieving an over 35-fold increase in potency, we identified structural modifications that improve the solubility and metabolic stability of the scaffold. The efficacy of two new compounds 12c (CCG-203592) and 12k (CCG-205363) against biofilm formation in Staphylococcus aureus represents a promising additional mode of action for this novel class of compounds.     

青藓科中国新记录种——短尖拟青藓

该文报道了短尖拟青藓［Sciuro-hypnum ornellanum (Molendo) Ignatov & Huttunen］在新疆阿尔泰山的分布,这是该种在中国的首次记录。详细介绍了拟青藓属［Sciuro-hypnum （Hampe） Hampe］的由来,讨论了短尖拟青藓的形态特征及其地理分布,对其与形态相近种进行了比较分析,并提供了中国拟青藓属分种检索表。该种的发现不仅为中国青藓科植物研究提供了新资料,同时也进一步佐证了中国新疆植物区系与俄罗斯、中亚及欧洲的密切联系。     

食指固定定位法在桡动脉采血中的应用

目的 探讨食指固定定位法在桡动脉采血中的应用效果.方法 将250例患者随机分为观察组130例和对照组120例,对照组使用传统的食指和中指固定定位法采集桡动脉血,观察组使用食指固定定位法采集桡动脉血,比较两组采血一次穿刺成功率.结果 两组桡动脉采血一次穿刺成功率比较,差异有统计学意义(P＜0.05).结论 采用食指固定定位法采集桡动脉血可以提高一次穿刺成功率.     

ERK介导的炎性反应参与肾缺血再灌注损伤

目的研究小鼠肾缺血再灌注损伤的发病机制。方法建立小鼠肾缺血再灌注损伤模型。12只雄性C57BL／6随机分为2个组（n=6）,分别为假手术组（Sham）,肾缺血再灌注损伤模型组（IRI）。IRI组血管夹夹闭左肾动脉,置于32℃温箱后1h松开血管夹,去除右肾。Sham组操作同上,但不夹闭左肾动脉。再灌注24h后处死小鼠,收集血清和肾脏标本。测定血清肌酐（Cr）和血尿素氮（BUN）。PAS染色后显微镜下观察肾脏形态学变化,Western印迹分析ERK、p-ERK的表达,PCR检测MCP-1、IFN-γ。结果与假手术组（Sham）相比,IRI组血清肌酐、血尿素氮明显升高,病理检查可见肾脏内肾小管上皮细胞明显肿胀坏死、蛋白管型形成明显,还可观察到炎性细胞浸润明显增加。ERK、p-ERKWestern印迹结果PCR显示MCP-1、TNF-α也明显上调,但ERK表达不变。结论在肾缺血再灌注中,ERK激活介导的炎性后府可能参与了肾扣伤。     

Tau蛋白高度磷酸化致阿尔茨海默病动物模型研究进展

阿尔茨海默病（Alzheimer＇sdisease,AD）是老年人中最常见的神经退行性疾病,以过度磷酸化tau蛋白为核心形成的神经原纤维缠结为AD的主要病理特征之一。近年来对tau蛋白磷酸化的研究备受关注。在AD的实验研究中,探索理想的AD动物模型对于明确AD的病因、发病机制及药物的研发等方面起关键作用。本文对Tau蛋白磷酸化致AD主要动物模型的研究进展进行了综述,包括Tau转基因动物模型、激酶和磷酸化酶系统失衡致Tau蛋白过度磷酸化损伤模型、降低Tau蛋白糖基化致Tau过度磷酸化模型等。     

不同剂量鱼藤酮对拟帕金森病模型大鼠行为学及纹状体多巴胺含量的影响

目的观察不同剂量鱼藤酮皮下注射对大鼠行为学及脑纹状体多巴胺含量的影响,探讨鱼藤酮拟帕金森病大鼠模型的适宜造模条件。方法Lewis大鼠分别给予鱼藤酮不同剂量（1．0、1．5和2．0ms／ks／d）皮下注射共28d。应用旷场实验和斜板实验分别测定大鼠的运动功能和协调性,高效液相色谱一电化学法检测大鼠纹状体内多巴胺含量。结果模型组大鼠存活率随鱼藤酮注射剂量的升高呈逐渐下降趋势。鱼藤酮2．0mg／kg组大鼠体重最先明显降低,随着注射时间的延长,各模型组大鼠均出现显著的体重降低。旷场实验结果显示,各剂量鱼藤酮组大鼠跨格次数和站立次数均明显下降。斜板实验结果显示,鱼藤酮1．5mg／kg组大鼠在斜板的停留角度较对照组显著减小。鱼藤酮I．5ms／kg组大鼠脑纹状体内多巴胺含量显著降低。结论鱼藤酮1．5ms／kg皮下注射28d,大鼠出现明显的运动功能障碍和脑内多巴胺含量减少,而死亡率相对较低,因此是建立帕金森病大鼠模型的适宜剂量。     

Long-term effects of simulated acid rain stress on a staple forest plant, Pinus massoniana Lamb: a proteomic analysis

At present, acid rain has become one of the top ten global environmental issues. Acid rain causes slower growth, injury, or decline of forests. Some dramatic effects on forests have been observed in south China since the late 1970s and the situation is deteriorating. We carried out a comparative proteomic analysis on Pinus massoniana Lamb, a staple tree species widely distributed in middle and south China to gain a better understanding of tree response to acid rain at molecular level. Two-year-old P. massoniana saplings were treated with simulated AR (SiAR) or control solution, respectively, for 8 months. The changes in total protein profile of P. massoniana leaves were studied using two-dimensional differential gel electrophoresis (2D-DIGE). Among the total protein spots reproducibly detected on each gel, 65 spots representing 28 proteins were identified to be differentially regulated. These proteins were annotated in various biological functions, such as photosynthesis and energy metabolism, secondary metabolism, protein stability, amino acid and nitrogen metabolism and defense. Down-regulation of four key enzymes in the Calvin cycle identified that biomass loss by SiAR was mainly due to the inhibition of carbon fixation. Primary energy metabolisms involved in sucrose biosynthesis, glycolytic pathway and Krebs cycle, etc., were also disturbed after SiAR treatment. Specifically, most of up-regulated proteins were related to secondary metabolism, protein stability and defense, suggesting that in response to SiAR stress, plants started a variety of metabolic pathways to prevent cells from damage. Different from the herbaceous plants suffering SiAR, it revealed that secondary metabolites in P. massoniana play pivotal roles against SiAR. Protemoic techniques were demonstrated a reliable and robust tool to expand our understanding of differentially expressed proteins associated with acid rain stress on P. massoniana. Functional analysis of these proteins further revealed biochemical and physiological basis of the plant in response to acid rain and would provide strategies for breeding new acid rain tolerant tree species. To our knowledge, it is the first proteome report on the forest plant suffering long-term acid rain stress.     

Synthesis, characterization, and DNA binding of a novel ligand and its Cu(II) complex

A novel naphthalene-2,3-diamine-2-salicylaldehyde (NS) ligand and its mononuclear copper(II) complex (CuNS) have been synthesized and structurally characterized. The UV–vis absorption and emission spectra of NS showed obvious changes on addition of Cu²⁺ solution. The interaction of the compounds with calf thymus DNA and G-quadruplex DNA were investigated by spectroscopic methods and thermal melting assay. The nucleolytic cleavage activity of the compounds was investigated on double-stranded circular pBR322 plasmid DNA and G-quadruplex DNA by electrophoretic mobility shift assay. The results show that CuNS has a greater ability to stabilize G-quadruplex DNA over calf-thymus DNA. The cytotoxicity of the compounds toward HpeG2 cancer cells was also studied, and they showed significant potential for antineoplastic effects.     

Optimization of soluble human interferon-γ production in Escherichia coli using SUMO fusion partner

Interferon-γ (IFN-γ) is a broad-spectrum antiviral glycoprotein that produced by lymphatic T cells and natural killer cells those who had stimulated by antigen. Human IFN-γ (hIFN-γ) often used in clinical research and practice because of its bioactivity, for example, antivirus, antitumor, controlling cell apoptosis, and the strict selectivity. However, due to the difficulties of Escherichia coli expression system meet in protein folding, the hIFN-γ often existed as inclusion body. The production of soluble hIFN-γ can be developed to shorten the production cycle and decrease the cost. In this study, small ubiquitin-related modifier fusion technology was used to express and purify recombinant hIFN-γ. Expression induced by adding 50 mM arginine and 1 % (w/v) glycerol into the culture at 24 °C existed as a soluble form of 70 % in total protein. Finally, about 62 mg recombinant hIFN-γ was obtained from 1 L fermentation culture with no less than 96 % purity. Determined by cytopathic effect inhibition assay, the specific activity of the recombinant hIFN-γ achieved at 7.78 × 10⁵ IU/mL.