A case-control study of risk factors for severe hand-foot-mouth disease in Yuxi,China, 2010–2012

正Dear Editor,Here,we report the risk factors for severe hand-foot-mouth disease(HFMD)determined by our case-controlstudy.Our findings could help disease prevention and in-tervention initiatives.Patients with severe HFMD displayfatal clinical manifestations with sequelae,requiring≥7days of hospitalization.A tota1 of 249 severe cases treat-ed at Yuxi Children’s Hospital were included in the case     

TGFα对肝癌细胞SMMC-7721增殖和ERK蛋白的影响

目的观察TGFα诱导肝癌细胞增殖和对信号传导因子ERK蛋白表达的影响.方法应用MTT比色法观察不同浓度TGFα对肝癌细胞SMMC-7721的增殖作用.用流式细胞术检测TGFα对肝癌细胞凋亡和细胞周期的影响.用免疫组化方法检测TGFα对ERK蛋白表达影响.结果 1μg/L TGFα作用24h SMMC-7721细胞增殖率为3%(P>0.05);作用48h后增殖率达16%(P<0.05).5μg/L TGFα作用24h增殖率达18%(P<0.05);作用48h增殖率达24%(P<0.01),增殖效应呈时间、剂量依赖性.5μg/L TGFα作用肝癌细胞48h能抑制肝癌细胞凋亡,使细胞滞留于G2M期,增加PI.5μg/L TGFα能促进ERK蛋白在细胞核中的表达.结论 TGFα能促进肝癌细胞增殖,增加ERK蛋白在细胞核中的表达.     

MAPK和JAK—STAT途径中酪氨酸蛋白激酶在肝癌组织中的表达及意义

目的观察MAPK途径和JAK—STAT途径中重要酪氨酸蛋白激酶ERK、P38、C-Jun、JAK、STAT3、STAT5在肝癌组织中的表达及其相互关系,探讨蛋白激酶表达与肝癌患者临床病理特征之间的关系。方法收集原发性肝癌手术切除标本30例,制作组织芯片,酪氨酸蛋白激酶在不同组织中的表达检测采用免疫组化SP法。结果ERK、P38、C-Jun、JAK、STAT3、STAT5在肝癌组织中的表达平均光密度值显著高于肝硬化组（P〈0．01）。ERK与C-Jun、JAK、STAT3、STAT5在肝癌组织中的表达呈显著正相关,与P38呈显著负相关。JAK的过度表达与肝癌组织的分化程度有关,在低分化肝癌组织中表达率显著高于高中分化肝癌组织。结论MAPK和JAK—STAT通路的过度活化在肝癌发生发展过程中起重要作用,细胞信号转导系统失去正常的协调平衡可能是导致肿瘤发生的重要原因。     

α-1,4-Glucan lyase,a new class of starch/glycogen-degrading enzyme

Antibodies have been raised against an -1,4-glucan lyase purified from the red alga Gracilariopsis lemaneiformis (Bory) Dawson, Acleto et Foldvik. Localization of -1,4-glucan lyase in ultra-thin sections of the red alga was performed using immunogold/transmission electron microscopy. The enzyme was found exclusively in the stroma of the chloroplasts of the algal cells, not in the cell wall, cytosol or around the cytosolic starch granules. Partial amino-acid sequences of the algal lyase, with a total length of 100 amino-acid residues, were obtained. No sequence homology was found with proteins and peptides of known sequences.This work was supported by grants from the Swedish Council for Planning and Coordination of Research (FRN), Carl Tryggers Foundation, and Hierta-Retzius Fund. We thank Ms Katrin Österlund and Anette Axén for their expert technical assistance with this work.     

珍珠粉治疗兔眼角膜烫伤作用的实验研究

本文将淡水珍珠粉治疗兔眼角腹烫伤的实验研究所采用的料材、方法、结果进行了总结。实验结果表明:珍珠粉治疗实验性烫伤的兔眼与不用珍珠粉的对照组比较,疗效有显著性差异;从病理切片也见到治疗组组织结趋构向于正常;停药三个月后,治疗组所形成的角膜翳小。     

Intense visible multicolored luminescence from lanthanide ion‐pair codoped NaGdF4 nanocrystals

Lanthanide ion‐pair (Eu³⁺/Tb³⁺, Dy³⁺/Tb³⁺, Sm³⁺/Tb³⁺ and Eu³⁺/Dy³⁺) codoped NaGdF₄ nanocrystals using Ce³⁺ as the sensitizer were prepared via the polyol method. The nanocrystals with different codoped lanthanide ion‐pairs retain their individual optical properties and the combined spectra can be detected using single‐wavelength excitation at about 251 nm. The combined spectra intensity ratios can be adjusted through control of the doping ions molar ratios. Excited with a UV lamp at 254 nm, the as‐prepared nanocrystals in aqueous solution emit intense visible emissions of different colors. The nanocrystals were coated with SiO₂, to make them biocompatible. Copyright © 2009 John Wiley & Sons, Ltd.     

Components of human complement system. Testing and isolation of C4

A modified reagent for testing the hemolytic activity of human complement component C4 has been obtained. Reagent R4 was obtained by treatment of human blood serum pools with 0.075 M solution of hydrazine hydrate. This reagent was found to be rich in the serum fraction obtained by chromatography on DEAE-cellulose DE-52 and containing an active complement C3 component. To test the sensitivity and specificity of the reagent, component C4 was subjected to purification. This procedure resulted in a hemolytically active, electrophoretically and immunoelectrophoretically homogeneous component C4. DEAE-cellulose DE-52, DEAE-Sephacel, Ultragel AcA-34 and, again, DEAE-Sephacel were used consecutively as purification agents. The activity yield of component C4 with regard to the initial serum level was 20%.     

多重实时荧光PCR检测牛、山羊和绵羊源性成分

根据牛、山羊和绵羊线粒体细胞色素b基因序列, 设计特异性引物和以不同荧光素标记的Taqman探针。通过对PCR反应体系和反应条件的优化筛选, 建立能同时鉴别牛、山羊和绵羊源性成分的多重实时荧光PCR方法。采用本文方法与国标GB/T 20190-2006方法分别对17种不同源性动物DNA和200份不同来源样品DNA进行牛羊源性成分检测, 数据显示两者检测结果符合率达100%, 特异性相当。与国标方法相比, 本试验方法不需电泳、酶切和测序, 即可在一个PCR反应中同时鉴别检测牛、山羊和绵羊3种源性成分, 检测效率提高近3倍; 灵敏度更高, 比国标方法灵敏10倍; 适用性更广, 除了饲料, 还适用于肉品、奶品、生皮和动物油脂等动物产品的牛羊源性成分检测。     

Catabolism of 1,5-anhydro-D-fructose in Sinorhizobium morelense S-30.7.5: discovery, characterization, and overexpression of a new 1,5-anhydro-D-fructose reductase and its application in sugar analysis and rare sugar synthesis

The bacterium Sinorhizobium morelense S-30.7.5 was isolated by a microbial screening using the sugar 1,5-anhydro-D-fructose (AF) as the sole carbon source. This strain metabolized AF by a novel pathway involving its reduction to 1,5-anhydro-D-mannitol (AM) and the further conversion of AM to D-mannose by C-1 oxygenation. Growth studies showed that the AF metabolizing capability is not confined to S. morelense S-30.7.5 but is a more common feature among the Rhizobiaceae. The AF reducing enzyme was purified and characterized as a new NADPH-dependent monomeric reductase (AFR, EC 1.1.1.-) of 35.1 kDa. It catalyzed the stereoselective reduction of AF to AM and also the conversion of a number of 2-keto aldoses (osones) to the corresponding manno-configurated aldoses. In contrast, common aldoses and ketoses, as well as nonsugar aldehydes and ketones, were not reduced. A database search using the N-terminal AFR sequence retrieved a putative 35-kDa oxidoreductase encoded by the open reading frame Smc04400 localized on the chromosome of Sinorhizobium meliloti 1021. Based on sequence information for this locus, the afr gene was cloned from S. morelense S-30.7.5 and overexpressed in Escherichia coli. In addition to the oxidoreductase of S. meliloti 1021, AFR showed high sequence similarities to putative oxidoreductases of Mesorhizobium loti, Brucella suis, and B. melitensis but not to any oxidoreductase with known functions. AFR could be assigned to the GFO/IDH/MocA family on the basis of highly conserved common structural features. His6-tagged AFR was used to demonstrate the utility of this enzyme for AF analysis and synthesis of AM, as well as related derivatives.     

Production of enzymatically active recombinant full-length barley high pI alpha-glucosidase of glycoside family 31 by high cell-density fermentation of Pichia pastoris and affinity purification

Recombinant barley high pI alpha-glucosidase was produced by high cell-density fermentation of Pichia pastoris expressing the cloned full-length gene. The gene was amplified from a genomic clone and exons (coding regions) were assembled by overlap PCR. The resulting cDNA was expressed under control of the alcohol oxidase 1 promoter using methanol induction of P. pastoris fermentation in a Biostat B 5 L reactor. Forty-two milligrams alpha-glucosidase was purified from 3.5 L culture in four steps applying an N-terminal hexa-histidine tag. The apparent molecular mass of the recombinant alpha-glucosidase was 100 kDa compared to 92 kDa of the native barley enzyme. The secreted recombinant enzyme was highly stabile during the 5-day fermentation and had significantly superior specific activity of the enzyme purified previously from barley malt. The kinetic parameters Km, Vmax, and kcat were determined to 1.7 mM, 139 nM x s(-1), and 85 s(-1) using maltose as substrate. This work presents the first production of fully active recombinant alpha-glucosidase of glycoside hydrolase family 31 from higher plants.