Sorption of metals by extracellular polymers from the cyanobacterium Microcystis aeruginosa fo. flos-aquae strain C3-40

The sorption of cadmium (II), copper (II), lead (II),manganese (II), and zinc (II) by purified capsularpolysaccharide from the cyanobacterium Microcystis aeruginosafo. flos-aquae strainC3-40 was examined by four methods: equilibriumdialysis, metal removal from solution as detected byvoltammetry, metal accumulation by capsule-containingalginate beads, and calorimetry. The polysaccharide'ssaturation binding capacities for these metals rangedfrom 1.2 to 4 mmol of metal g^-1 of capsule, whichcorresponds to 1 metal equivalent per 2 to 4saccharide subunits of the polymer. Competitionbetween paired metals was tested with simultaneous andsequential additions of metal. Cadmium (II) andlead (II), as well as lead (II) and zinc (II), competedrelatively equally and reciprocally for polymerbinding sites. In contrast, manganese (II) stronglyinhibited the binding of cadmium (II) and lead (II), butitself was not substantially inhibited by either theprior or simultaneous adsorption of cadmium (II) or lead (II).The data are interpreted with respect to overlap ofbinding sites and possibilities of altered polymerconformation or solvation. Calorimetric studies oflead (II) and cadmium (II) association reactions withthe polysaccharide suggest that the enthalpies aresmall and that the reactions may be driven by entropy.     

Distribution of actin bundles in Bowman's capsule of rat kidney

In this study we define the distribution of actin bundle arrangement in Bowman's capsule of rat renal corpuscles. Parietal cells of Bowman's capsule were examined by conventional light microscopy, electron microscopy and confocal microscopy. Within each parietal cell individual actin bundles are arranged in a parallel fashion running the length of the cell. Computer reconstructions obtained using confocal microscopy clearly show the lengths of actin bundles to be arranged, on a capsule level, end-to-end, at angles and perpendicular to bundles in adjacent cells. The bundles stain positively for non-muscle myosin and vinculin. The presence and arrangement of actin bundles in parietal cells is consistent with a role in reinforcing capsule structure.     

Selection of capsule deficient strains of Methylobacterium rhodesianum producing polyhydroxybutyrate

Methylobacterium rhodesianum was cultivated using an extended fed-batch regime. After treatments with N-nitroso-methyl-urea or X-rays, colonies showing an irregular morphology or increased heavy-metal sensitivity were selected. Electron micrographs of cells of isolated strains demonstrated the loss of the glycocalyx. Selectants and the parental strain yielded identical PHB amounts.     

鳅鮀鱼类鳔囊结构及系统发育研究(鲤形目:鲤科)

本文应用分支系统学原理对鳅(鱼它)鱼类的鳔囊、鳔及相关结构进行了特征分圻,并以(鱼句)亚科作为外类群。解剖结果表明,鳅(鱼它)鱼类的鳔分四种类型;分析结果进一步证实鳅(鱼它)鱼类是一个单源群,作为一亚科可分为异鳔鳅(鱼它)属和鳅(鱼它)属,后者又分为原鳅(鱼它)和鳅(鱼它)二个亚属。     

Adaptation of signature-tagged mutagenesis to Escherichia coli K1 and the infant-rat model of invasive disease

With the exception of the polysialic acid capsule (K1 antigen), little is known about other virulence factors needed for systemic infection by Escherichia coli K1, the leading cause of Gram-negative neonatal meningitis in humans. In this work, the functional genomics method of signature-tagged mutagenesis (STM) was adapted to E. coli K1 and the infant-rat model to identify non-capsule virulence genes. Validation of the method was demonstrated by the failure to recover a reconstructed acapsular mutant from bacterial pools used to systemically infect 5-day-old rats. Three new genes required for systemic disease were identified from a total of 192 mutants screened by STM (1.56% hit rate). Gut colonization, Southern blot hybridization, mixed-challenge infection, and DNA sequence analyses showed that the attenuating defects in the mutants were associated with transposon insertions in rfaL (O antigen ligase), dsbA (thiol:disulfide oxidoreductase), and a new gene, puvA (previously unidentified virulence gene A), with no known homologues. The results indicate the ability of STM to identify novel systemic virulence factors in E. coli K1.     

疏风解毒胶囊辅以综合管理干预对慢性阻塞性肺疾病患者呼吸及运动功能的影响

摘要 目的：探讨疏风解毒胶囊辅以综合管理干预对慢性阻塞性肺疾病（COPD）患者呼吸及运动功能改善的影响。方法：选取2018年10月-2019年10月到我院进行治疗的COPD患者84例作为研究对象,随机数字表法分为两组,患者均使用疏风解毒胶囊进行治疗,对照组（n=42）予以常规干预,试验组（n=42）进行综合管理干预。对比两组患者的临床治疗有效率、肺功能改善情况、肺功能指标、呼吸困难指数（MRC）评分以及6分钟步行实验（6MWT）结果。结果：试验组的临床治疗有效率高于对照组（P<0.05）。干预后,两组动脉血二氧化碳分压（PaCO₂）和MRC评分较干预前降低（P<0.05）,动脉血氧分压（PaO₂）、动脉血氧饱和度（SaO₂）、第1秒用力呼气容器（FEV₁）、用力肺活量（FVC）、FEV₁/FVC均较干预前升高（P<0.05）,6MWT距离较干预前增加（P<0.05）,且试验组上述指标改善情况更优（P<0.05）。结论：疏风解毒胶囊辅以综合管理干预可提高COPD患者的临床治疗效果,改善其肺功能,可有效缓解呼吸困难,提升运动强度,值得在临床上应用与推广。     

天香胶囊对晕动病模型大鼠行为学与前庭核c-fos蛋白表达的影响

目的:观察中药复方天香胶囊对晕动病模型大鼠行为学与前庭核c-fos蛋白表达的影响。方法:选择雄性SD大鼠并将其随机分为正常组、模型组、阳性药组、天香胶囊低、中、高剂量组。灌胃预给药3天后,采用双轴旋转刺激法建立大鼠晕动病模型,通过晕反应指数评分、自发活动实验、异嗜高岭土实验检测各组大鼠行为学变化,Western blotting法与免疫组化法检测各组大鼠前庭核c-fos蛋白的表达。结果:与正常组大鼠相比,模型组大鼠晕反应指数和高岭土摄入量均显著增高,自发活动总路程与次数均显著减少,前庭核c-fos蛋白表达水平显著增高;与模型组相比,天香胶囊可显著降低晕动病模型大鼠晕反应指数与高岭土摄入量,提高自发活动总路程与活动次数,降低大鼠前庭核组织c-fos蛋白表达。结论:天香胶囊可有效改善晕动病模型大鼠的行为学变化,其作用机制可能与下调前庭核c-fos表达有关,提示降低前庭核兴奋性可能是天香胶囊抗晕动病的内在机制之一。     

综述:中药治疗阿尔茨海默病的作用特点

阿尔茨海默病(AD)是一种多因素相关的复杂性疾病,目前临床治疗效果不佳．仅针对单靶点或单致病途径的药物不易取得好的疗效．另一个重要原因是干预时机太晚,当诊断出痴呆时患者脑内已有大量神经元死亡．因此,应当针对多靶点、多途径治疗,同时将治疗时机提前到痴呆发生前,才有可能在AD的药物干预领域实现新的突破．本文综述了作者近十多年来在中药治疗AD方面的研究工作,包括中药新复方参乌胶囊、中药提取物何首乌二苯乙烯苷、山茱萸环烯醚萜苷、淫羊藿黄酮和淫羊藿苷对多种拟AD动物模型和细胞模型的影响及其作用机制．这些中药的特点是作用在AD复杂发病机制的多靶点和多途径,尤其是具有神经保护和神经营养/再生作用,且对线粒体和突触具有明显的保护作用,可望用于AD的早期干预或轻度认知障碍期(MCI)的治疗,从而阻止或延缓痴呆的发生与进程．     

双胶润通胶囊润肠通便功能的研究

目的:探讨双胶润通胶囊的润肠通便作用的效果及剂量.方法:实验采用动物试验,将小白鼠(雌雄各半,体重18～22 g)分成两个实验组,每组50只,实验一组进行小肠推进试验,实验二组进行排便试验,时间均为7 d.按推荐剂量每人每日5 g设计,分为低、中、高3个剂量组,另设空白对照和模型对照组.结果:在不影响小鼠体重的情况下,双胶润通胶囊高剂量组小肠推进率与模型对照组比较差异均有显著性变化(P《0.05);3个剂量组小鼠的首便时间、粪便粒数均高于便秘模型对照组,差异具有极显著性差异(P《0.01);结论:双胶润通胶囊对小鼠小肠运动有增强作用,并能缩短小鼠首便时间、增加小鼠的粪便粒数与重量,即:具有润肠通便作用.     

肺炎克雷伯菌荚膜糖蛋白ELISA检测方法的研究

以肺炎克雷伯菌荚膜糖蛋白为免疫原,获得了兔抗肺炎克雷伯菌荚膜糖蛋白抗血清,通过硫酸铵分级沉淀与吸附法相结合的方法对抗血清进行纯化,并在此基础上建立了肺炎克雷伯菌荚膜糖蛋白间接ELISA检测方法.该检测方法的检测灵敏度为0.031 mg/L,线性检测范围为2.5～30.0 mg/L,批内误差为1.04％～3.22％,批间误差为2.61％～8.35％.