产单核细胞李斯特菌P60蛋白的可溶性表达

以食品中分离到的L.mXFL0605株为试验菌株,PCR扩增得到iap全基因。将iap连接到pET-28a(+)载体进行原核表达,分别采用培养温度为25℃或37℃,IPTG浓度为5μg/mL或10μg/mL优化组合进行诱导。结果显示,当采用37℃培养和10μg/mLIPTG诱导时可以获得部分可溶性表达的p60,重组p60蛋白分子质量约60 ku。     

一株无血凝性兔出血症病毒的分离鉴定及其衣壳蛋白VP60基因的克隆和序列分析

从临床病料中分离鉴定出1株无血凝性的致病性兔出血症病毒（RHDV），命名为Yaan-1。HA试验测得该毒株原代及经兔体传3代后的肝毒在25℃、37℃和4℃时均无血凝性；但在琼脂扩散试验和对流免疫电泳中均可见分离株与常规RHDV高免血清形成清晰的沉淀线；电镜观察可见30nm左右的病毒粒子。采用RT-PCR方法将Yaan-1株的衣壳蛋白VP60基因进行了克隆测序，序列分析表明VP60基因序列全长1740bp，编码579个氨基酸，测序结果提交GenBank（注册号为DQ069280），并与世界各国的常规RHDV分离株进行比较，结果表明核苷酸同源性为90．0％～98．0％，氨基酸同源性为94．1％～99．0％，氨基酸变异多发生在衣壳蛋白C、E区；同时对Yaan-1株的分子量、等电点、疏水性、跨膜区等分子结构特征进行了分析。本研究首次报道了无血凝性RHDV中国分离株，丰富了地方毒株资源，为明确我国地方株的分子流行病学，以及对VP60蛋白分子特征研究提供了新材料。     

Lethal effect of VEGFR2shRNA on HL60 cells in vitro using lentiviral vector

AIM: To look for harmfulless anti-leukemia drug with selective high performance, lethal effect of small hairpin RNA (shRNA) on VEGFR₂ gene expression of tumor cell line HL60 in vitro.METHODS: The most effective VEGFR₂ siRNA was designed and screened. The shRNA oligo was designed and pU6/VEGFR₂ entry clone was constructed. HL60 was transfected transiently and vascular endothelial growth factor receptor 2(VEGFR₂) expression was tested with MTT assay, RT-PCR and Western blotting. The expression clone was constructed and cotransfected with ViraPowerTM Packaging Mix into 293FTTM cells to produce Lentiviral vectors harboring Lenti6/shVEGFR₂. The virion supernatant was added into HL60 cells and VEGFR₂ gene inhibitory effect was determined. RESULTS: The inhibitory rates of VEGFR₂ siRNA c were high. VEGFR₂ expression in HL60 was inhibited by using pU6/VEGFR₂ entry clone constructed with shRNA and pENTRTM/U6. For HL60 cells, the inhibitory rate was 84.9%. The expression of VEGFR₂ mRNA and protein decreased significantly. 48 hours after transfection of pU6/shVEGFR₂ entry clone and transduction of Lenti6/shVEGFR₂ expression clone, the cell inhibitory rates were similar. Cell growth inhibitory rate of entry clone descended rapidly after this time point, the expression clone changed slowly, reaching the peak at 96 hours, dropped slightly, having no significance deviation. CONCLUSION: in vitro, VEGFR₂ shRNA using lentiviral vector blocks VEGF/VEGFR₂ self-secretion in HL60 cells, which inhibits leukemia development.     

60Co诱变方法选育高产多糖槐耳菌株

采用槐耳T菌株作为诱变材料,进行60Co射线的诱变试验（剂量为1000Gy,剂量率为10Gy·min^-1）,筛选出多糖含量高且适合栽培的新菌株T189,其多糖产量为37．13％,比槐耳T菌株（27．48％）提高35．1％。     

可移植的UART底层驱动构件设计

以飞思卡尔公司基于ARM Cortex-M4内核的K60系列微控制器为例,设计了一种具有较好可移植性和重用性的UART底层驱动构件．测试结果表明该构件正确而有效．     

Aerococcus viridans expression of Cpn60 is associated with virulence during infection of the American lobster, Homarus americanus Milne Edwards

The Gram-positive bacterium Aerococcus viridans var. homari is a well-documented causative agent of the lethal systemic disease gaffkemia in both the American lobster, Homarus americanus, and the European lobster, Homarus gammarus. Previous phenotypic characterization has been unsuccessful at differentiating avirulent from virulent strains without performing lethal animal infection trials. Recent genetic characterization of A. viridans strains through 16S rRNA sequencing and random amplification of polymorphic DNA fingerprinting has revealed the presence of two subtypes. However, subtype 1 contains both virulent and avirulent strains which are genetically identical. The purpose of this study was to determine the proteomic mediators of virulence in A. viridans. Quantitative proteomic mapping of these two strains has revealed 29 differentially expressed protein spots, seven of which are only expressed in the virulent strain and could act as virulence factors. One protein, chaperonin 60 (Cpn60), is uniquely expressed in the virulent strain and has been shown to act as a virulence factor in many other bacteria. The proteomic mapping strategy employed in this study is the first to show phenotypic differences between virulent and avirulent strains. Cpn60 expression represents a potentially useful tool for identifying the virulent strains of A. viridans in epidemiological studies.     

Mycobacterium salmoniphilum infection in farmed Atlantic salmon, Salmo salar L

Multiple greyish‐white visceral nodules containing abundant rapidly growing and acid‐fast bacteria, subsequently identified as Mycobacterium salmoniphilum, were detected in moribund and newly dead market‐sized fish during a period of increased mortality in an Atlantic salmon, Salmo salar, farm in western Norway. Isolates cultured from diseased fish were phenotypically consistent with Mycobacterium sp. previously isolated from Atlantic salmon [MT 1890 (= NCIMB13533), MT1892, MT1900 and MT1901] in the Shetland Isles, Scotland. Partial sequences of 16S rDNA, ribosomal RNA internal transcribed spacer (ITS1), 65‐kDa heat‐shock protein (Hsp65) and β subunit of RNA polymerase (rpoB) revealed 97‐99% similarity with M. salmoniphilum type strain ATCC 13758^T. The source of infection was not confirmed. Koch’s postulates were fulfilled following experimental challenge of Atlantic salmon with field isolate NVI6598 ( FJ616988 ). Mortality was recorded in experimentally infected fish; however, the infection remained subclinical in the majority of affected fish over the 131‐day challenge period.     

^60 Co-γ射线辐射对苋菜种子发芽率及幼苗生长的影响

用不同剂量的^60 Co-γ射线对苋菜种子进行辐射，观测其对苋菜种子发芽率和幼苗生长的影响。结果表明，在该实验设计的辐射剂量范围（20-200Gy）内，对苋菜种子有刺激生长的作用，20Gy有利于苋菜种子发芽，60～80Gy有利于苋菜幼苗的生长。     

丙氨酸-ESR剂量计用于测量产品箱内剂量分布的研究

本文用自制丙氨酸-ESR剂量计和西德辐射与环境研究中心(GSF)的丙氨酸-ESR剂量计,测量了北京市射线应用中心的~(60)Coγ辐射源(1.44×10~(16)Bq)辐照纸箱包装(913mm×555mm×460mm)产品箱时的吸收剂量分布,箱内模拟产品(报纸)的堆积密度为200ks/m~3,测量结果表明,产品箱內最大剂量D_(max)与最小剂量D_(min)之比分别为1.45(北京市辐射中心)和1.47(GSF),两者相差1.40％,在允许误差范围之内。     

HL-60 Cells Apoptosis Induced by Low-dose Cytosinearabinoside in Vitro

Cytosinearabinoside(Ara-C) is an important agent used for treatment of leukemia, but its mechanism of action at low dose is not clear, maybe is related to its effectson differentiationor apoptosis of cells. The authors investigate The relationship between bcl-2, p53 expression and apoptosis of HL-60 cells induced by low-dose cytosinearabinoside (10~(-8)M) by means of TUNEL method, flow cytometry, immunohistochemistry and in situ hybridization. The results show that low-doseAra-C could inhibit cell growth and induce apoptosis, and the effects might be related to increase of P53protein and decrease of bcl-2 mRNA expression.