Synthesis of three NH2-terminally extended arginine-vasopressins with prolonged biological activities

The synthesis of three novel AVP-analogues, extended by 1-3 amino acids at their NH2-2-termini in accordance with the sequence of the bovine arginine-vasopressin neurophysin II precursor, is reported. The compounds were assayed for their antidiuretic and vasopressor activities with particular attention to the duration of the effects. All compounds showed high potency, based on the intensity, and prolonged effects in both test systems compared with AVP.     

Peptides related to vasopressin in invertebrates

Summary Compounds chemically related to the vertebrate neurohypophysial peptides, vasopressin and neurophysin, have been detected in recent years in the brain and in ganglia of invertebrates. Most data acquired so far have been obtained in insects and in molluscs. Evidence suggesting that these compounds might exert neurohormonal and neurotransmitter functions in these species is reviewed.Work by the authors is supported in part by Swiss NSF grant 3.560.083.     

Localisation par immunofluorescence de peptides analogues à l'α-endorphine dans les ganglions infra-œsophagiens du lombricideDendrobaena subrubicunda Eisen

Summary Using an -endorphin antiserum in brain and infra-sophageal ganglions ofDendrobaena (Lumbricidae), positive immunoreaction was found in 4 cells of the infra-oesophageal ganglions: a pair of conic perikarya in the anterior region and a pair of pear-shaped elements close to the origin of the last nerve of the ganglion. No reaction was observed with -endorphin, or neurophysin or vasopressin antisera.     

Das Verhalten des Quotienten Harnstoff-N:Rest-N bei normalen und nephrektomierten,urämischen Ratten

Summary (1) The quotient urea nitrogen: non-protein nitrogen was determined in nephrectomized uremic rats and compared with the quotient in control animals. The quotient in nephrectomized uremic animals was 0.74, in control animals 0.35. The elevation of the quotient is of hepatic origin.(2) The desamination was increased in the liver of nephrectomized uremic animals in comparison to controls; the urea production was unchanged.     

超临界CO2萃取法提取库尔勒香梨精油及其成分分析研究

采用超临界CO2萃取法提取库尔勒香梨精油,用气相色谱-串联质谱技术对其成分进行分析,并对几种提取方法进行综合比较。结果表明,与水蒸气蒸馏法、固相微萃取法相比,超临界CO2萃取法具有香梨精油提取率最高,为0．0549％。感官分析的结果表明,超临界CO2萃取法所得的库尔勒香梨精油颜色为橙色透明液体,而且风味好。气相色谱-质谱联用（GC-MS）分析结果表明：超临界CO2萃取法所得的香梨精油中共鉴定出28种成分。丁酸乙酯、顺-7-十四烯-1-醇和乙酸己酯的含量最高,含量分别为5．19％、4．85％和4．37％。     

Novel and sensitive noncompetitive enzyme immunoassay for kassinin in rat plasma

A novel and sensitive noncompetitive enzyme immunoassay for kassinin is described. Kassinin was biotinylated using sulfosuccinimidyl-6-(biotinamido)hexanoate. The biotinylated kassinin was trapped on anti-kassinin IgG-coated polystyrene balls and, after washing to eliminate other biotinylated substances, was eluted with HCl. The biotinylated kassinin eluted was reacted with anti-kassinin Fab'-peroxidase conjugate and trapped onto streptavidin-coated polystyrene balls. Peroxidase activity bound to the polystyrene balls was assayed by fluorimetry. The detection limit of kassinin was 0.13 pg (0.1 fmol)/tube or 0.065 microgram/l of rat plasma, which was 750-fold or 15-fold lower than that for competitive radioimmunoassay.     

Über den Einfluss von Natriumsulfit,Natriumtellurit und Natriumselenit auf die Retention von Zink,Kadmium und Quecksilber im Organismus

Summary The influence of sodium sulfite, sodium tellurite and sodium selenite on the retention of zinc, cadmium and mercury in mice was studied. The retention of mercury was increased by sodium selenite and by sodium tellurite. The retention of cadmium was increased only by sodium selenite. Sodium sulfite did not influence the retention of metals studied. The retention of zinc was not influenced by any compounds used.     

New lectins and other putative adhesins in Aeromonas hydrophila

The ability of strains of Aeromonas hydrophila to bind 125I-labelled collagen types I and IV, fibronectin, laminin, lactoferrin, and immobilized mucins and orosomucoid on latex beads was found to be a property common to all the isolated strains. The binding was specific, was inhibited by homologous unlabelled glycoproteins, and was protease sensitive. The nature of the binding is discussed.     

An insect acetylcholinesterase inhibitor from compound eyes of Triatoma infestans (Hemiptera)

The presence of an acetylcholinesterase inhibitor in the compound eyes of adult Triatoma infestans was demonstrated. The inhibitory activity was localized in the ocular pigments separated by disc gel electrophoresis. The inhibitor was selective against insect acetylcholinesterase, reversible, noncompetitive and heart stable.     

Kinetic analysis of lactate dehydrogenase using integrated rate equations

The reaction catalyzed by lactate dehydrogenase was analyzed under fully second-order conditions using integrated rate equations. A two-step regression analysis was utilized to fit twenty-one progress curves repeated in sextuplicate to the general mechanism second-order integrated rate equation with additional terms for substrate inhibition. The fitting error was less than one percent. The resulting kinetic constants support a ternary complex mechanism; in no case were constants supporting another mechanism predicted. The inhibition constant for oxamate was also determined.     

纤维素分解混合菌群的筛选及腐解稻草研究Ⅱ纤维素分解混合菌群对稻草的腐解

对富集筛选的纤维素分解混合菌群进行了稻草腐解试验,结果表明：施用该纤维素分解混合菌群后能够减少氨态氮素的挥发,纤维素分解混合菌群在15d内对稻草的腐解效果明显,外观分散度明显比对照要好,对照的失重率为45．80％,而处理的失重率为57．85％,比对照提高了12．05个百分点。Duncan新复极差法分析表明,失重率在1％水平差异极显著,而还原糖量、纤维素酶活以及pH值的差异均不显著,说明还原糖量、纤维素酶活以及pH值不能作为判断稻草腐解程度的指标。得到了一个稻草腐解效果较好的混合菌群,能够在外界菌群存在的条件下较好腐解稻草。     

加替沙星-壳聚糖纳米粒胶联羊膜药膜的制备及体外实验研究

目的制备一种新型生物多功能复合材料——加替沙星．壳聚糖纳米粒胶联羊膜药膜,并观察其体外缓释性能及抑菌作用。方法采用离子胶联法制备加替沙星－壳聚糖纳米粒并检测其表征,然后将栽药纳米粒加入到纤维蛋白胶中,混匀后再与羊膜胶联制成加替沙星－壳聚糖纳米粒胶联羊膜药膜,光镜及扫描电镜下观察其形态学特征,高效液相色谱法测定其中加替沙星的浓度,微量肉汤稀释法检测其体外抑菌活性。结果加替沙星纳米粒的粒径为291±33nm,载药量为10．46％,包封率为61．32％。载有纳米药物的纤维蛋白胶与羊膜基底面粘合紧密,呈圆形的加替沙星纳米粒附着在胶原纤维的网状结构上。在体外,加替沙星－壳聚糖纳米粒胶联羊膜药膜可持续释药达15天,对金黄色葡萄球菌和铜绿假单胞菌的最低抑菌浓度分别为0．05μg／ml和0．42μg／ml。结论加替沙星－壳聚糖纳米粒胶联羊膜药膜在体外具有良好的缓释性能及抑茵作用。     

Distribution of glycerophosphorylcholine diesterase in rat brain.

The distribution of glycerylphosphorylcholine diesterase in the rat brain has been examined. The enzyme was evenly distributed throughout the brain but was localized in the synaptosome (nerve ending) fraction which was prepared by ultracentrifugation.     

An insect acetylcholinesterase inhibitor from compound eyes ofTriatoma infestans (Hemiptera)

Summary The presence of an acetylcholinesterase inhibitor in the compound eyes of adultTriatoma infestans was demonstrated. The inhibitory activity was localized in the ocular pigments separated by disc gel electrophoresis. The inhibitor was selective against insect acetylcholinesterase, reversible, noncompetitive and heat stable.This work was supported by a research grant from the Comisión de Investigaciones Cientificas de la provincia de Buenos Aires, Argentina.     

Inhibition of the NADP-linked glutamate dehydrogenase from Trypanosoma cruzi by silver nitrate.

The purified NADP-linked glutamate dehydrogenase from Trypanosoma cruzi was strongly inhibited by silver nitrate. The inhibition was reversed by reduced glutathione, and was modified by the presence of the substrates during preincubation of the enzyme with the inhibitor.     

Participation of microtubules and microfilaments in the transcellular biliary secretion of immunoglobulin A in primary cultures of rat hepatocytes

Summary The biliary secretion of immunoglobulin A (IgA) in primary hepatocyte cultures was investigated by means of immunofluorescence. The characteristic accumulation of IgA in visible bile canaliculi was found to be strongly inhibited by vinblastine and colchicine or by cytochalasin B, but its surface binding was not.The author thanks Prof. Dr D. Mecke for his support and encouragement. The excellent technical assistance of Mrs M. Behringer and Mrs A. Schneck is gratefully acknowledged. The author is grateful to the BIOTEST Serum Institut (Frankfurt) for the kind gift of human IgA. This work was supported by the Deutsche Forschungsgemeinschaft.     

Involvement of D-amino acid oxidase in elimination of D-serine in mouse brain

The physiological role of D-amino acid oxidase (EC 1. 4. 3. 3) in mouse brain is described. The presence of D-enantiomers of neutral common amino acids was surveyed in the brain. D-serine was shown to be present at high concentration only in regions where the enzyme activity was low. In normal mice whose D-amino acid oxidase activity was much higher in the cerebellum than in the cerebrum, free D-serine content was apparently lower in the cerebellum than in the cerebrum. In mice of a mutant strain lacking D-amino acid-oxidase activity, the free D-serine level was remarkably high both in the cerebrum and cerebellum. The results suggest that the enzyme is involved in the elimination of free D-serine in the cerebellum.     

Adrenaline and the electrogenic sodium pump in Rana catesbeiana sympathetic ganglion cells.

The effect of adrenaline on the Na+-pump in bullfrog (Rana catesbeiana) sympathetic ganglion cells was studied by use of electrophysiological methods. The rate of removal of excess Na+ injected into a ganglion cell was increased by adrenaline. The K+-activated hyperpolarization of cell membrane, which might be produced by an electrogenic Na+-pump, was also increased by adrenaline. These results suggested that adrenaline was able to accelerate the Na+-pump, possibly the electrogenic Na+-pump.     

家蚕体内不同部位的同步辐射成像分析

以五龄熟蚕为研究对象，对其体内不同部位进行同步辐射成像（包括同轴位相衬度成像和显微断层成像）。研究结果表明，蚕体内中部丝腺的直径范围在3．74～4．21mm之间，其始端距离蚕头部约18mm。而吐丝管则被发现于距离蚕头部顶端1．43mm处，且直径相对较细，范围在7～52μm之间。     

Novel and sensitive noncompetitive enzyme immunoassay for kassinin in rat plasma

Summary A novel and sensitive noncompetitive enzyme immunoassay for kassinin is described. Kassinin was biotinylated using sulfosuccinimidyl-6-(biotinamido)hexanoate. The biotinylated kassinin was trapped on antikassinin IgG-coated polystyrene balls and, after washing to eliminate other biotinylated substances, was eluted with HCl. The biotinylated kassinin eluted was reacted with anti-kassinin Fab'-peroxidase conjugate and trapped onto streptavidin-coated polystyrene balls. Peroxidase activity bound to the polystyrene balls was assayed by fluorimetry. The detection limit of kassinin was 0.13 pg (0.1 fmol)/tube or 0.065 g/l of rat plasma, which was 750-fold or 15-fold lower than that for competitive radioimmunoassay.