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Separation of chlorinated hydrocarbons and organophosphorus, pyrethroid pesticides by silicagel fractionation chromatography and their simultaneous determination by GC-MS

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Journal of Environmental Sciences 2004年第2期16卷 268-271页

作者： WANGLi-gang JIANGXin WANGFang BIANYong-rong StephanForster DieterMartens InstituteofSoilScience ChineseAcademyofSciencesNanjing210008China. InstituteofEcologicalChemistry NationalResearchCenterforEnvironmentandHealthNeuherberg85764Germany

A silicagel fractionation procedure for environmental sample extracts, which separates chlorinated hydrocarbons(CHCs) and organophosphorus, pyrethroid pesticides into two groups for subsequent instrumental analysis, was developed in this study. This method was achieved by optimizing the fraction cut-off volume of elution and different solvents. Using fully activated silica gel and cut-off CHCs collection after 10 ml 10% dichloromethane (DCM) in n-hexane passing through the column resulted in satisfactory separation of CHCs and organophosphorus, pyrethroid pesticides. This procedure had a higher reliability for CHCs than for organophosphorus, pyrethroid pesticides, because there is a relatively reliable recovery for CHCs. This approach is less expensive due to reducing sample pre-treatment time and solvent consumption.

关键词： CHCs organophosphorus pesticides pyrethroid pesticides silicagel fractionation

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Effect of linear alkyl benzene sulfonates (LAS)on the fate of phenanthrene in a model ecosystem (water-lava-plant-air)

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Journal of Environmental Sciences 2004年第3期16卷 513-519页

作者： JIANGXia JINXiang-can YANChang-zhou AyferYediler OUZi-qing AntoniusKettrup ChineseResearchAcademyofEnvironmentalScienceBeijing100012 China GSF-nationalresearchcenterforenvironmentandhealth InstituteofEcologicalChemistry.lngolstaedterLandstraβe185764NeuherbergGermany InstituteofAppliedEeology ChineseAcademyofSciencesShenyang110015China

Advanced closed chamber system was used to study the fate of phenanthrene (3 rings PAHs) in the presence of linear alkylbenzene sulphonates(LAS). The results showed mineralization and metabolism of phenanthrene are fast in the “culture solution lava plant air' model ecological system. The distribution proportions of applied 14 C activity in this simulative ecological system were 41%—45%, 14% to 10% and 1% in plant, lava and culture solution respectively, and 18% to 29%, 11% to 8% recovered in the forms of VOCs and CO 2. Main parts of the applied 14 C activity exist in two forms, one is polar metabolites(25%) which mainly distribute in the root(23%), the other is unextractable part(23%) which have been constructed into plant root(8 98%), shoot(0 53%) or bonded to lava(13 2%). The main metabolites of phenanthrene were polar compounds(25% of applied 14 C activity), and small portion of 14 C activity was identified as non polar metabolites(6% of applied 14 C activity) and apparent phenanthrene(1 91% of applied 14 C activity). Phenanthrene and its metabolites can be taken up through plant roots and translocated to plant shoots. The presence of LAS significantly increased the the concentration of 14 C activity in the plant and production of VOCs, at the same time it decreased the phenanthrene level in the plant and the production of CO 2 at the concentration of 200 mg/L.

关键词： phenanthrene LAS plant closed chamber systems

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Maintaining cholesterol homeostasis: Sterol regulatory element-binding proteins

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World Journal of Gastroenterology 2004年第21期10卷 3081-3087页

作者： LutzW.Weber MeinradBoll AndreasStampfl 554MarinerPointDrive ClintonTN37716USA InstituteforToxicology GSF-NationalResearchCenterforEnvironmentandHealthMunichD85758NeuherbergGermany

The molecular mechanism of how hepatocytes maintain cholesterol homeostasis has become much more transparent with the discovery of sterol regulatory element binding proteins (SREBPs) in recent years. These membrane proteins aremembers of the basic helix-loop-helix-leucine zipper (bHLHZip) family of transcription factors. They activate the expression of at least 30 genes involved in the synthesis of cholesterol and lipids. SREBPs are synthesized as precursor proteins in the endoplasmic reticulum (ER), where they form a complex with another protein, SREBP cleavage activating protein (SCAP). The SCAP molecule contains a sterol sensory domain. In the presence of high cellular sterol concentrations SCAP confines SREBP to the ER. With low cellular concentrations, SCAP escorts SREBP to activation in the Golgi. There, SREBP undergoes two proteolytic cleavage steps to release the mature, biologically active transcription factor, nuclear SREBP (nSREBP). nSREBP translocates to the nucleus and binds to sterol response elements (SRE) in the promoter/enhancer regions of target genes. Additional transcription factors are required to activate transcription of these genes. Three different SREBPs are known, SREBPs-1a, -1c and -2. SREBP-1a and -1c are isoforms produced from a single gene by alternate splicing. SREBP-2 is encoded by a different gene and does not display any isoforms. It appears that SREBPs alone, in the sequence described above, can exert complete control over cholesterol synthesis, whereas many additional factors (hormones, cytokines, etc.) are required for complete control of lipid metabolism. Medicinal manipulation of the SREBP/SCAP system is expected to prove highly beneficial in the management of cholesterol-related disease.

关键词：内环境平衡胆固醇保护作用固醇调整元素粘合物蛋白 SREBPs

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昆明山海棠诱导Jurkat等3个细胞株发生细胞凋亡

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科学通报 1999年第11期44卷 1168-1173页

作者：曹佳 MichaelNusse 第三军医大学预防医学系分子毒理室重庆400038 nationalresearchcenterforenvironmentandhealth

为研究昆明山海棠 (THH)的药理和毒理作用 ,通过流式细胞仪检测发现THH对Jurkat,CHE和NIH3T3细胞均有较强的致凋亡作用 ,但Jurkat淋巴瘤细胞更为敏感 ,每皿 5 0 μLTHH作用 48h后 ,可使 93%的肿瘤细胞凋亡 .使用Annexin V Fluos检测Jur... 详细信息

为研究昆明山海棠 (THH)的药理和毒理作用 ,通过流式细胞仪检测发现THH对Jurkat,CHE和NIH3T3细胞均有较强的致凋亡作用 ,但Jurkat淋巴瘤细胞更为敏感 ,每皿 5 0 μLTHH作用 48h后 ,可使 93%的肿瘤细胞凋亡 .使用Annexin V Fluos检测Jurkat细胞 ,结果发现THH作用 0 5h后即可出现早期细胞凋亡 (细胞膜损害 ) ,4～ 6h后 15 0～ 2 0 0 μLTHH组膜损伤率可高达 85 %,证明THH首先是损伤细胞膜 ,再发展为细胞凋亡的 .

关键词：细胞凋亡昆明山海棠药理海棠 Jurkat CHE

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