DL-酒石酸的诱导拆分

将(±)-酒石酸制成其钠铵盐,在27℃以下进行诱导拆分,得(+)-和(-)-酒石酸钠铵,经转化为钙盐,再处理精制可得合格的(+)-和(-)-酒石酸。总收率为91%以上。     

Immunochemical and biochemical analyses of myosin light chains from normal and denervated cardiac muscle

Rabbit antisera were prepared against the combined low molecular weight subunits (the light chains) of canine cardiac myosin. The antisera reacted specifically with the light chains and with purified myosin. There were no immunochemical reactions with the heavy myosin chains. The antisera were then used to test preparations of light chains isolated from hearts maintained in a denervated condition for 12, 4, or 2 weeks prior to killing the animals. Denervation was accomplished by mediastinal neural ablation. The light chains prepared from the denervated hearts all reacted with the antisera and showed immunological identity with the light chains from control muscle. The specific adenosine triphosphatase activity of myosin prepared from hearts denervated for 12, 4, or 2 weeks exhibited a marked deviation from control activity. We concluded that, although cardiac denervation did not affect the immunological properties of myosin light chains, the biological activity of cardiac myosin was greatly reduced after 2 weeks of denervation and recovered somewhat after 4 weeks.     

Analysis of cell-cycle kinetics and sulfur amino acid metabolism in methionine-dependent tumor cell lines; the effect of homocysteine supplementation

Methionine dependence is a feature unique to cancer cells, exhibited as inability to grow in a methionine-depleted environment supplemented with homocysteine, the immediate metabolic precursor of methionine. This study explores the effect of methionine depletion and homocysteine supplementation on the viability, sulfur amino acid metabolism and cell-cycle kinetics of normal and cancer cells, as well as their ability to recover from the treatments. An array of cells including hepatomas (HTC, Phi-1), prostate adenocarcinomas (PC-3) and transformed (3T3) and normal (HS-27) fibroblasts, has been used aiming to evaluate the importance of tissue specificity. All cell lines proliferated well in methionine-complete media (M+H-), whilst only the normal fibroblasts HS-27 grew in methionine-depleted homocysteine-supplemented media (M-H+). None of the tested cell lines were able to grow in media without methionine or homocysteine (M-H-). HTC was the only cell line that did not recover from the M-H+ treatment whilst PC-3 did not recover from the M-H- treatment. Methionine and homocysteine depletion (M-H+ and M-H-) were found to induce arrest at different phases of the cell cycle, depending on the cell line: the methionine-dependent HTC, PC-3 and 3T3 arrested at the S and G2/M phase, whilst Phi-1 and the methionine-independent HS-27 accumulated in the G1 phase. The cell-cycle kinetics showed that the observed blockades were reversible. The information resulting from these studies is important for not only the behavior of cancer cells, but also for appreciating the potential of developing cancer therapies based on methionine-depletion strategies.     

Synthesis and structure-activity relationship of di-(3, 8-diazabicyclo[3.2.1]octane) diquaternary ammonium salts as unique analgesics

Based on the structure characteristics of the lead compounds, 1, 1' octanedioyl-4, 4'-dimethyl-4, 4'-dibenzyl dipiperazinium dibromide (2) and 3, 8-disubstituted-3, 8-diazabicyclo [3.2.1]octanes (DBO), di-(3, 8-diazabicyclo [3.2.1]octane) diquaternary ammonium salts 3 a-c were designed and synthesized through a highly practical procedure. Target compounds 3 a-c and the hydrochloride salts of their precursors 10 a-c were evaluated for their in vivo analgesic and sedative activities. Interestingly, the introduction of an endoethylenic bridge in the piperazine of lead compound 2 causes loss of the analgesic activity and increases the toxicity dramatically. This result shows that the flexible conformation of piperazine in compound 2 is favorable for interaction with the receptor, and the quaternization of compounds 10 a-c is the main reason for the toxicity increase.     

Effect of zinc and benzalkonium chloride on Nitrosomonas communis and potential nitrification in soil

A bacterial contact assay is described which uses a chemoautotrophic microorganism, Nitrosomonas communis (strain Nm2) to evaluate the biological effect of contaminated soils. The effects of two toxicants on the ammonium oxidation activity of the autochthonous microbial population in the soil are compared with inhibition of the same biological response in the new monospecies bioassay. Experiments were performed using soil samples dosed with organic and inorganic contaminants (benzalkonium chloride and zinc) to demonstrate the mode of operation and the sensitivity of the bioassay. The EC50 values of zinc and benzalkonium chloride were calculated to be 171 and 221 mg kg-1 soil, respectively. The toxic response provided by the bioassay can thus predict the effect of soil pollutants on the autochthonous nitrifying bacteria.     

氟哌啶醇季铵盐衍生物的生物活性研究

目的:探讨氟哌啶醇季铵盐衍生物F8～F13的离体扩冠活性及对麻醉大鼠整体血流动力学的影响,并分析构效关系.方法:采用生物检定法,观察20 μmol/L目的化合物对KC1诱导的猪冠脉螺旋条收缩曲线的影响;麻醉正常血压SD大鼠,经右颈总动脉插管至左心室,右股动脉插管后,分别5 mg/kg静脉注射6个目的化合物,BL-420型生物机能实验系统记录观察血流动力学效应.结果:F11和F13均具强的降压作用:其中F13兼具良好的扩冠活性,同时在其降低血压的同时可能对SD大鼠具心功能抑制作用,而F11对大鼠心功能无影响.结论:苄基苯环上以对位或邻位甲基取代者更适合作为进一步研究与开发心血管药物的理想先导物.     

A Comparative Study of Direct Hemoperfusion and Hemodialysis for the Removal of Glufosinate Ammonium

Abstract

BASTA® is a herbicide containing glufosinate ammonium 18.5% and a surface-active agent. There were six fatalities in 34 cases of glufosinate ammonium poisoning reported by the Japan Poison Information Center. To evaluate efficacy in the removal of glufosinate ammonium from the blood, two bottles were prepared containing 600 mL of heparinized bovine blood with 1 mL or 3 mL of BASTA. Direct hemoperfusion or hemodialysis was performed for two hours at a flow rate of 50 mL/min. The final glufosinate ammonium concentration of the blood bottle containing 1 mL of BASTA decreased to 96.9% of the initial concentration after direct hemoperfusion and to 0.5% after hemodialysis. The final glufosinate ammonium concentration of the bottle containing 3 mL of BASTA decreased to 62.2% after direct hemoperfusion and to 0.9% after hemodialysis. Hemodialysis is more effective than direct hemoperfusion for removal of glufosinate ammonium from blood.     

氨对星形胶质细胞超微结构的影响

目的：在体外实验条件下观察氨对星状胶质细胞超微结构的影响。材料与方法：用ＮＨ４Ｃｌ造成高高ＮＨ４环境，对体外培养之星形胶质细胞的形态变化进行了超微结构观察。结果：高ＮＨ４环境下，星菜胶质细胞首先表现出损伤性变化，细胞电子密度降低，线粒体、内质网等细胞器肿胀，在胞质内形成许多单位膜包绕的电子密度降低的空泡区域，以后随着氨浓度加大或／和氨作用的时间延长，细胞内成份开始出现增生修复现象，次级溶酶体数量增