Changes in glycosaminoglycan sulfation and protein kinase C subcellular distribution during differentiation of the human colon tumor cell line Caco-2

Summary During the spontaneous differentiation (day 5 to day 15 of the culture) of Caco-2 cells, the sulfation of cell layer glycosaminoglycans increased, whereas protein kinase C activity was concomitantly redistributed from the membrane to the cytosol. The protein kinase C activators, 4-phorbol 12-myristate, 13-acetate and 1,2-dioctanoyl-glycerol inhibited glycosaminoglycan sulfation. By contrast, 4-phorbol 12, 13 didecanoate was ineffective.These results suggest that membrane-bound PKC may exert a modulatory effect on glycosaminoglycan sulfation, and this effect is gradually attenuated as Caco-2 cell differentiation progresses.     

邻苯二甲酸酯对海洋藻类的致毒效应

采用评价化学药品对藻类毒性的标准方法，对邻苯二甲酸醋与海洋藻类的相互影响进行探讨．通过对邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙醋(DEP)、邻苯二甲酸二丁醋(DBP)海洋藻类的致毒试验，分别得出此3种物质对三角褐指藻、盐藻、等边金藻、中肋骨条藻48h、96h的半致死浓度，探讨了上述几种海洋藻类对DMP、DEP、DBP的忍受限度．     

土壤中邻苯二甲酸酯的净化分离方法研究

确定了土壤中邻苯二甲酸酯的高效液相色谱分析方法。用石油醚／丙酮（Ｖ／Ｖ∶３／１）超声萃取土壤样品，微型硅胶柱净化预分离，浓硫酸纯化，最后用高效液相色谱紫外检测器检测土壤中的邻苯二甲酸酯，土壤中邻苯二甲酸酯的添加回收率在８８５％～１０５０％之间，检测极限在８～１３ｎｇ／ｇ之间     

邻苯二甲酸酯类增塑剂降解研究进展

邻苯二甲酸酯(PAEs)被广泛用于增塑剂行业。近年的研究表明邻苯二甲酸酯具有环境激素的作用,由此引起的环境问题得到世界的普遍关注。在概括介绍邻苯二甲酸酯类增塑剂的种类、结构以及其对环境和人类的危害的基础上,论述了近年来在邻苯二甲酸酯类化合物的降解方面所取得的最新进展,重点讨论并比较了邻苯二甲酸酯的光解和生物降解,指出了目前邻苯二甲酸酯光解和生物降解研究的局限及今后的发展方向。     

分散液液微萃取在酸性模拟体系中塑料包装材料PAEs的溶出应用

将分散液液微萃取(DLLME)与气相色谱-氢火焰离子化检测器(GC-FID)技术相结合,建立了一种简单快速测定塑料包装材料在酸性模拟体系(体积分数为3%乙酸水溶液)中6种邻苯二甲酸酯(PAEs)溶出量的方法.采用四氯化碳作萃取荆,乙腈为分散剂,在优化条件下,6种PAEs在1.0～100.0μg/L质量浓度内呈良好的线性...     

11－脱氧甘草次酸衍生物的合成（Ⅱ）

用甘草次酸还原制得１１－脱氧甘草次酸，以此为原料分别与乙酸酐、丙酸酐、顺丁烯二酸酐、正己酸酐和邻苯二甲酸酐反应生成酯，再分别同金属化合物反应制得１２种１１－脱氧甘草次酸酯类和盐类衍生物，具有潜在的药理活性和应用前景。用ＩＲ、ＨＮＭＲ、ＭＳ和元素分析确证了它们的结构，并对其光谱性质进行了讨论．     

红外光谱法测定丙烯酸酯悬浮共聚竞聚率

本文对丙烯酸丁酯和丙烯酸乙酯的共聚合作了研究.并采用均聚共混方法制备标准样品,由红外光谱法分别测定标准样品和共聚样品中乙基和羧基的相对峰高。从而测得共聚大分子链节比(摩尔),最后用YBR法求得二元共聚竞聚率,从而判断丙烯酸丁酯和丙烯酸乙酯的共聚组成。     

相转移催化合成乙酸苄酯香料

用氯化苄和乙酸钠为原料，以相转移催化法合成乙酸苄酯香料。提出了最佳工艺条件和反应过程中催化剂、过剩反应物料循环利用的可行性。结果表明，转化率高达９９％，选择性为９８％～１００％；产品收率在９０％～９５％．工艺过程简单，副反应很少，是乙酸苄酯生产的一条高产、优质、低成本的有效途径。     

Ⅴ-Ti催化剂低氧催化氧化邻二甲苯制苯酐——Ⅱ.TiO_2晶体结构及助剂作用的影响

研究了V-Ti体系中TiO_2晶体结构与催化活性的联系,本系统中,当焙烧温度超过650℃,由于TiO_2由锐钛矿型转变为金红石型,使催化活性降低。助剂作用的ESCA、XRD、LRS研究表明,与通常V-Ti系催化剂不同,本催化剂由于助剂的作用,使V=O键减弱而利于活化;且随K助剂含量增加,V_2O_(4.33)晶胞的001面取向优化加强,更宜于催化活性的充分显示。     

Degradation of pyrene and characterization of<Emphasis Type="Italic">Saccharothrix</Emphasis> sp. PYX-6 from the oligotrophic Tianchi Lake in Xinjiang Uygur Autonomous Region,China

Bacterial strain PYX-6 that utilizes anthracene,phenanthrene, or pyrene for carbon and energy sources for growth was isolated from a non-polluted lake (Tianchi Lake) in Xinjiang Uygur Autonomous Region of China. Its morphology, physiological and biochemical properties, cell wall pattern and G C mol% content of DNA molecules were characterized. The 16S rRNA gene of strain PYX-6 was sequenced and analyzed for similarities to related bacterial species. Results indicated that strain PYX-6 is a member of the Genus Saccharothrix, and the strain was named Saccha-rothrix sp. PYX-6. When pyrene was the sole carbon source in cultural medium, the strain PYX-6 assimilated pyrene for growth and 0.005% of yeast extract stimulated pyrene degradation and assimilation. The optimal pH of cultural medium and the optimal shaking frequency during cultivation were 6-8 and 200 r/m, respectively. It was found that the disappearance of pyrene in medium occurred before significant growth of strain PYX-6 took place. Phthalic acid, benzylacetic acid, and benzylpropenoic acid were detected as catabolic intermediates during pyrene degradation with mass spectroscopy and this result indicated that Saccharothrix sp.PYX-6 adopted a pathway that is different from the pathway of the previously reported pyrene-degrading Mycobacterium sp. PYR-1.