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Sample records for benzopyrenes

  1. P-glycoprotein in adriamycin-resistant cells functions as an efflux pump for benzopyrene, a chemical carcinogen

    Energy Technology Data Exchange (ETDEWEB)

    Chao Yeh, G.; Poore, C.M.; Lopaczynska, J.; Phang, J.M. (NCI-FCRDC, Frederick, MD (United States))

    1991-03-15

    The physiological function of multidrug resistant gene (MDR 1) coded P-glycoprotein 170 (P-gp) in normal tissues remains unknown. The authors propose that P-gp functions as an efflux pump in normal tissues for benzopyrene and other xenobiotic substances. To examine their hypothesis the authors used a series of MDR human breast cancer MCF-7 cells with increasing degrees of drug resistance, expression of MDR and levels of P-gp. First, they found the IC{sub 50} for benzopyrene is linearly correlated with the levels of P-gp at different stages of adriamycin resistant MCF-7 cells. Using P-gp ({sup 3}H)azidopine labeling as a measurement of P-gp they found benzopyrene competes for labeling of P-gp. Finally, they directly measured cellular efflux of benzopyrene with adherent cell laser cytometry and found that resistant cells expressing high levels of P-gp showed rapid efflux of benzopyrene. By contrast, drug sensitive wild type cells with undetectable P-gp showed negligible efflux. They conclude that P-gp can function as an efflux pump for benzopyrene and suggest that P-gp may be a cellular mechanism for resistance to carcinogens.

  2. The Curative Activity of Isolated Fraction from Spathodea campanulata Beauv Stem Bark on Rat’s Exposed to Benzopyrene

    Directory of Open Access Journals (Sweden)

    Masruri Masruri

    2014-11-01

    Full Text Available This paper reports a screening results of the secondary metabolites composed in Spathodea campanulata Beauv stem bark, evaluate inhibiting activity of malondialdehyde (MDA on rat’s cancer model exposed with benzopyrene, and the histology of its lung. The secondary metabolite of the stem bark fraction consisted of alkaloids, flavonoids-phenolic, terpenoid and steroid compounds. The isolated fraction contained of these metabolites significantly indicate bioactivity by reducting of malondialdehyde (MDA level, and also histology appearance of the lung tissue prepared from the benzopyrene-exposed rat indicated a curative activity.

  3. Role of bacteria in the removal of benzopyrene from waste water in the coke by-products industry

    Energy Technology Data Exchange (ETDEWEB)

    Yurovskaya, E.M.

    1985-12-01

    Role of specific microflora is studied (the phenol destroying pseudomonad Pseudomonas aeruginosa and a rare strain of thionic bacteria Thiobacillus thiocyanoxidans which breaks down thiocyanates), in biochemical purification installations for removing benzopyrene from coal-tar effluent. Tests are described made in synthetic media with phenol and thiocyanate concentrations of 200 mg/l and 50 mg/l respectively, in waste water from coking plants and in ordinary industrial effluent, in order to study their resistance to benzopyrene and the capacity for intracellular accumulation and biochemical transformation as well as distribution in the biocenosis of purifying installations. The tests were also carried out in elective synthetic media with benzopyrene concentrations varying from 10-200 ..mu..g/l to discover a possible role of phenol destroying pseudomonad and thionic bacteria in decarcinogenization of waste water. The data obtained make it possible to assume that the widely used microbiological method for removing dangerous ingredients (phenols, thiocyanates, cyanide) from waste water will also help to reduce the amount of benzopyrene carcinogenic compound by approximately 49.4-56.04%. 11 references.

  4. Prevention of chinese green tea on 3,4-benzopyrene-induced lung cancer and its mechanism in animal model

    Directory of Open Access Journals (Sweden)

    Qihua GU

    2008-08-01

    Full Text Available Background and objective Chinese green tea is one of the daily consumption beverages in the world and is considered a promising cancer chemopreventive agent. In the present study, we investigate the role of lung cancer prevention by green tea and its mechanism. Methods Three groups of female SD rats were kept with the same feed. Rats in group A were administrated with 1% green tea drinking, while in group B and group C with water only. Animals in group A and group B were given 3,4-benzopyrene-corn oil mixture pulmonary injection fortnightly for 4 times, while in group C corn oil only. Rats were sacrificed 1 year after the first injection under narcotism. Lung tumors and lung tissues were performed H&E staining for cancer identification. Each case of lung cancer was examined for expression of p53 and Bcl-2 with in situ hybridization analysis and immunohistochemistry staining. Results No cancer was found in rats in group C. However, in group B, 15 out of 20 rats were found generating lung cancer, and in group A, 6 out of 20 rats inducing lung cancer were recorded. The rate of lung carcinogenesis in rats was decreased from 75% to 30% by 1% chinese green tea oral administration (χ2=8.12, P0.05. However, significantly lower level of Bcl-2 expression was found in lung cancer tissues of group A than that of group B (P<0.05. Conclusion The results indicate that chinese green tea inhibits lung carcinogenesis. Chinese green tea can slightly upregulate expression of p53, but significantly downregulate expression of Bcl-2 in lung cancer, and this may be related to the mechanism of lung cancer prevention.

  5. Macrophages promote benzopyrene-induced tumor transformation of human bronchial epithelial cells by activation of NF-κB and STAT3 signaling in a bionic airway chip culture and in animal models

    OpenAIRE

    Li, Encheng; Xu, Zhiyun; Zhao, Hui; Sun, Zhao; Wang, Lei; Guo, Zhe; Zhao, Yang; GAO, ZHANCHENG; Wang, Qi

    2015-01-01

    We investigated the role of macrophages in promoting benzopyrene (BaP)-induced malignant transformation of human bronchial epithelial cells using a BaP-induced tumor transformation model with a bionic airway chip in vitro and in animal models. The bionic airway chip culture data showed that macrophages promoted BaP-induced malignant transformation of human bronchial epithelial cells, which was mediated by nuclear factor (NF)-κB and STAT3 pathways to induce cell proliferation, colony formation...

  6. 苯并芘对鱼类免疫毒性作用的研究进展%Advances in Studies of Toxicological Effects of Benzopyrene on Fish Immune System

    Institute of Scientific and Technical Information of China (English)

    贾旭淑; 宋超; 陈家长

    2013-01-01

    [目的]综述了苯并芘对鱼类免疫毒性作用的研究进展.[方法]以主要免疫因子为切入点,综述了苯并芘对鱼类免疫毒性的作用机制及途径,以及环境中其他有机污染物对鱼类免疫毒性的作用机理.[结果]鱼类的免疫系统处于进化的特殊阶段,研究苯并芘对鱼类免疫功能的影响具有重要意义.[结论胲研究为应对在鱼类养殖过程中有机污染物及其他环境因子引起的免疫损伤,加强鱼类自身的免疫力提供了基础.%[Objective] The paper was to summarize the advances in studies of toxicological effects of benzopyrene on fish immune system.[Method] With the main immune factors as the breakthrough points,the paper summarized the toxicity mechanism and pathway of benzopyrene on fish immune system,as well as the toxicity mechanism of other environmental organic pollutants on fish immune toxicity.[Result] Fish immune system was in the special stage of evolution,the study on effect of benzopyrene on fish immune system has great significance.[Conclusion] The paper provided basis for dealing with the immune toxicity caused by organic pollutants and other environmental factors in aquaculture so as to strengthen fish immunity.

  7. Removal of 3,4-Benzopyrene in Coal Tar Pitch and Mechanism Research%脱除煤沥青中3,4-苯并芘及其机理研究

    Institute of Scientific and Technical Information of China (English)

    宋健伟; 李其祥; 王红亮; 王智勇; 伍林

    2014-01-01

    Using polyethylene glycol and s-trioxane (proportion 4∶6)as complex modifier,carcinogenic pol-ycyclic aromatic hydrocarbon 3,4-benzopyrene in coal tar pitch was removed by polymer modified method with removal rate of 7 6.0%.The elemental analysis results showed that in modified coal tar pitch,C,S element con-tents decreased,H element content increased,C/H value and aromaticity (fa)decreased,indicated that the sof-tening point of modified coal tar pitch and the stability of the system decreased.IR Spectra analysis indicated that reaction between polyethylene glycol and 3,4-benzopyrene belonged to O-alkylation reaction,reaction be-tween s-trioxane and 3,4-benzopyrene belonged to C-alkylation reaction.%以聚乙二醇和三聚甲醛为复合改性剂,采用聚合物改性法脱除煤沥青中致癌多环芳烃3,4-苯并芘,在复合改性剂比例(聚乙二醇与三聚甲醛的比)为4∶6时脱除率可达76.0%。元素分析结果表明,改性煤沥青的 C、S元素含量降低,H元素含量升高,C/H值和芳香度(fa )降低,说明改性煤沥青的软化点降低、体系的稳定性下降。红外光谱分析结果表明,聚乙二醇与3,4-苯并芘的反应属于 O-烷基化反应,三聚甲醛与3,4-苯并芘的反应属于C-烷基化反应。

  8. 苯并芘对鱼类免疫毒性作用的研究进展%Advances in the Study of Toxicological Effects of Benzopyrene on Fish Immune System

    Institute of Scientific and Technical Information of China (English)

    贾旭淑; 宋超; 陈家长

    2012-01-01

    As a representative of polycyclic aromatic hydrocarbons, Benzopyrene was widespread in the natural environment. It could be metabolized by cytochrome P450 monooxygenase such as CYP1A1. The ultimate metabolite BaP-7,8-dihydrodiol-9,10-epoxide thought to be critical for its immunotoxic activity. Fish immune system was in the special stage of evolution. This paper overviewed the toxicity mechanisms and channels of Benzopyrene on fish immune system from mainly immune factors. And the main immunostimulants used in aquaculture to deal with the immune toxicity caused by organic pollutants and other environmental factors were also briefly discussed.%苯并芘作为多环芳烃类化合物的代表,在自然环境中广泛存在.其主要毒性作用机制是经细胞色素P450单加氧酶代谢活化的产物7,8-二羟基-9,10-环氧苯并芘,这也是产生免疫毒性的关键物质.鱼类的免疫系统处于进化的特殊阶段,本研究以主要免疫因子为切入点,综述了苯并芘对鱼类免疫毒性的作用机制及途径.指出:环境中存在的其他有机污染物对鱼类免疫毒性的作用机理,并就鱼类养殖过程中为应对有机污染物及其他环境因子引起的免疫毒性所使用的免疫增强剂做了简单的介绍.

  9. 高效液相色谱法快速测定植物油中苯并(а)芘残留量%Determination of Benzopyrene in Vegetable Oil by High Performance Liquid Chromatography

    Institute of Scientific and Technical Information of China (English)

    陈佩玲

    2015-01-01

    A method for determination of benzopyrene in vegetable oil by High Performance Liquid Chromatography was established. Using C18 reversed-phase column, with acetonitrile and H2O (88∶12,v/v) as mobile phase,flow rate was 1.0 ml/min, and excitation wavelength was 384nm and emission wavelength was 406 nm, and column temperature was 35℃, and injection volume was 10μl. Results: The detection limit was 0.5μg/kg, and the recovery rate arange from 95% to 103%, and RSD was≤ 2.7%.%采用C18反相色谱柱,在流动相为乙腈∶水(88∶12,v/v),流速为1.0 ml/min,激发波长384 nm,发射波长406 nm,柱温35℃,进样量10μl 的条件下,建立高效液相色谱法快速测定植物油中苯并芘残留量的方法。结果:本法检出限为0.5μg/kg,加标回收率95%~103%,RSD≤2.7%。

  10. Macrophages promote benzopyrene-induced tumor transformation of human bronchial epithelial cells by activation of NF-κB and STAT3 signaling in a bionic airway chip culture and in animal models.

    Science.gov (United States)

    Li, Encheng; Xu, Zhiyun; Zhao, Hui; Sun, Zhao; Wang, Lei; Guo, Zhe; Zhao, Yang; Gao, Zhancheng; Wang, Qi

    2015-04-20

    We investigated the role of macrophages in promoting benzopyrene (BaP)-induced malignant transformation of human bronchial epithelial cells using a BaP-induced tumor transformation model with a bionic airway chip in vitro and in animal models. The bionic airway chip culture data showed that macrophages promoted BaP-induced malignant transformation of human bronchial epithelial cells, which was mediated by nuclear factor (NF)-κB and STAT3 pathways to induce cell proliferation, colony formation in chip culture, and tumorigenicity in nude mice. Blockage of interleukin (IL)-6 or tumor necrosis factor (TNF)-α signaling or inhibition of NF-κB, STAT3, or cyclinD1 expression abrogated the effect of macrophages on malignant transformation in the bionic airway chip culture. In vivo, macrophages promoted lung tumorigenesis in a carcinogen-induced animal model. Similarly, blockage of NF-κB, STAT3, or cyclinD1 using siRNA transfection decreased the carcinogen-induced tumorigenesis in rats. We demonstrated that macrophages are critical in promoting lung tumorigenesis and that the macrophage-initiated TNF-α/NF-κB/cyclinD1 and IL-6/STAT3/cyclinD1 pathways are primarily responsible for promoting lung tumorigenesis.

  11. 固相萃取-超高效液相色谱荧光法测定植物油中苯并(a)芘%Determination of Benzopyrene in Cooking Oil by Solid-Phase Extraction Coupled with Ultra Performance Liquid Chromatograph-Fluorescence Detection

    Institute of Scientific and Technical Information of China (English)

    王红青; 韩里明; 屠海云; 林伟杰

    2012-01-01

    采用中性氧化铝小柱净化样品,建立固相萃取一超高效液相色谱荧光法测定植物油中苯并(a)芘的方法。样品以正己烷为提取剂,净化、蒸发浓缩后正己烷溶解,荧光检测器检测。流动相为乙腈.水(75:25,wy),流速0.5mL/min,外标法定量。苯并(a)芘在0.10~50.0μg/L质量浓度范围内线性关系良好,相关系数Rz为0.9998;在空白样品中添加3个水平的标准品,回收率在91.7%~97.5%之间,相对标准偏差均小于2%(n=3);最低检出限为0.01ug/kg,定量限为0.03ug/kg。方法操作简便、分析时间短、稳定性好、选择性好、灵敏度高,为植物油中苯并(a)芘的测定提供参考。%A method was developed for the determination of benzopyrene by solid-phase extraction on a neutral A1203 cartridge coupled with ultra performance liquid chromatography (UPLC). Benzopyrene in samples were extracted into n-hexane, cleaned up, and concentrated by rotary evaporation and dissolved in n-hexane again before chromatographic separation and fluorescence detection. The mobile phase was acetonitrile-water (75:25, V/V) at a flow rate of 0.5 mL/min. Benzopyrene was quantified by external standard method. A good linear relationship between peak area and benzopyrene concentration was achieved in the range of 0.10--50.0 μg/L (R2- 0.9998). The mean spike recovery rates of benzopyrene at three concentration levels were in the range of 91.7% -- 97.5%, with relative standard deviation (RSD) of less than 2%. The limits of detection (LOD) and quantification (LOQ) were 0.01 g/kg and 0.03 vtg/kg, respectively. The developed method is characteristics of simple operation, good reproducibility, high sensitivity, and rapid, reliable and suitable determination for benzopyrene in cooking oil.

  12. Experimental Study on Lung Cancer Model Induced by Bronchial Perfusion of 3, 4-benzopyrene in Pigs%3,4-苯并芘支气管灌注构建猪肺癌模型的实验研究

    Institute of Scientific and Technical Information of China (English)

    陈锦润; 杨立民; 张震; 王维; 赵珍

    2013-01-01

    目的:探讨3,4-苯并芘经气管导管支气管灌注构建猪肺癌模型的可行性.方法购置24头实验猪,随机分为模型组、对照组,每组12头.实验猪麻醉满意后行气管插管,经气管导管向模型组支气管内注入3,4-苯并芘-玉米油混合液,对照组注入等量玉米油.每周灌注1次,连续16周.于第16周、32周、48周对全部实验猪行肺部CT扫描,观察肺部有无病灶.第48周解剖实验猪肺、食管、胃肠道、肝及脑等脏器,观察有无肿瘤形成,并对肿块及实验猪的肺组织切片进行苏木素伊红( hematoxylin and eosin, HE)染色分析.结果对照组肺部CT及解剖均未发现肺部肿瘤.模型组中,8头肺部CT显示有不同部位、大小不等的占位性病变,病理学均证实为恶性肿瘤,其中3头中分化腺癌,2头高分化鳞癌,1头肺泡细胞癌,2头腺鳞癌.4头肺部CT无异常,其中一头食管距声门2 cm处有一2 cm×1.5 cm×1.0 cm肿块,标本送病理检查证实为食管磷癌.另外3头及对照组肺部CT及解剖均未发现肿瘤.模型组实验猪1 a内成功诱发恶性肿瘤,总成瘤率75%,肺部成瘤率为66.66%.结论经气管导管支气管内灌注3,4-苯并芘是一种简便、安全可靠的肺癌动物模型的构建方法.%Objective To investigate the feasibility of pig lung cancer model induced by bronchial perfusion of 3,4-benzopyrene. Methods 24 experimental pig were randomly divided into model group and control group, each containing 12 cases. Experimental pigs were under the anaesthetic state, pigs in the model group were given endobronchial infusion of 3,4 - benzopyrene - corn oil mixture, pigs in control group were injected with equal capacity of corn oil.Perfusion 1 times a week for 16 weeks.In week 16,32 and 48,all experimental pig were given lung CT scans, then the lung lesions were observed.After 48 weeks, the pig lung, esophagus, and gastrointestinal tract

  13. DNA methylation analysis using CpG microarrays is impaired in benzopyrene exposed cells

    International Nuclear Information System (INIS)

    Epigenetic alterations have emerged as a key mechanism involved in tumorigenesis. These disruptions are partly due to environmental factors that change normal DNA methylation patterns necessary for transcriptional regulation and chromatin compaction. Microarray technologies are allowing environmentally susceptible epigenetic patterns to be mapped and the precise targets of environmentally induced alterations to be identified. Previously, we observed BaP-induced epigenetic events and cell cycle disruptions in breast cancer cell lines that included time- and concentration-dependent loss of proliferation as well as sequence-specific hypo- and hypermethylation events. In this present report, we further characterized epigenetic changes in BaP-exposed MCF-7 cells. We analyzed DNA methylation on a CpG island microarray platform with over 5400 unique genomic regions. Depleted and enriched microarray targets, representative of putative DNA methylation changes, were identified across the genome; however, subsequent sodium bisulfite analyses revealed no changes in DNA methylation at a number of these loci. Instead, we found that the identification of DNA methylation changes using this restriction enzyme-based microarray approach corresponded with the regions of DNA bound by the BaP derived DNA adducts. This DNA adduct formation occurs at both methylated and unmethylated CpG dinucleotides and affects PCR amplification during sample preparation. Our data suggest that caution should be exercised when interpreting data from comparative microarray experiments that rely on enzymatic reactions. These results are relevant to genome screening approaches involving environmental exposures in which DNA adduct formation at specific nucleotide sites may bias target acquisition and compromise the correct identification of epigenetically responsive genes

  14. Studies on air and water pollution. I. Polychlorinated biphenyls and benzopyrene status report July 1977 - June 1978

    International Nuclear Information System (INIS)

    An analytical methodology developed for trace amounts of polychlorinated biphenyls (PCB's) in water was described. The water sample was extracted with hexane and the extract passes through a florisil column. The cleaned extract was concentrated and then analyzed by gas chromatography using an electron capture detector. The methodology has an efficiency of 85% recovery for PCB spiked at a concentration level of 1 ppm. Minimum detection limit obtained was 0.5 ppm PCB in water. A total of 27 water samples were collected and analyzed during the period January - June 1978. No PCB's were detected in the samples. (author)

  15. Effects of chemical carcinogens of hemopoiesis, immunopoiesis and viral oncogenesis. Technical progress report, December 1, 1977--September 30, 1978. [Mechanisms of potentiation of viral leukemogenesis by MMS, benzopyrene, and DMBA

    Energy Technology Data Exchange (ETDEWEB)

    OKunewick, J.P.; Raikow, R.B.; Meredith, R.F.

    1978-10-01

    During the past year we have concentrated on defining the circumstances under which methyl methanesulfonate (MMS), benzo(a) pyrene (BP), and 7,12-dimethylbenz(a)anthracene (DMBA) interact with Friend virus (FLV) to produce leukemia. The optimum scheduling for each and also the effective dose levels of the chemicals have been partially determined. There are at least three critical factors which govern whether or not a leukemogenic interaction can be shown between the chemical agents and the virus. These are chemical dose, virus dose, and their relative time of administration. The most critical of these is virus dose. The optimum virus dose is that which results in between 25 and 40% incidence of leukemia within 40 days after virus infection when virus is given alone. The chemical carcinogens have a lower dose threshold, below which no significant potentiating effect can be observed. The only upper limit would appear to be acute drug toxicity. The third element, timing, is equally critical and varies according to the chemical. This variation may reflect different mechanisms of action by the chemical agents and/or different pharmacology. Data on the effects of MMS, BP, and DMBA on the immune system have indicated that the viral enhancement is probably not dependent on this function. Further enhancement of the potentiation of viral leukemogenesis was observed using benzo(a)pyrene and caffeine, indicating that the inhibition by caffeine of DNA repair may be an important factor in virus potentiation. (ERB)

  16. 苯并[a]芘和镉暴露对食蚊鱼求偶行为的影响%Effects on the courtship behavior of mosquitofish(Gambusia affinis) exposed to 3,4-benzopyrene (BaP) and cadmium (Cd2+)

    Institute of Scientific and Technical Information of China (English)

    苏方; 谢勇平; 方展强

    2013-01-01

    研究苯并[a]芘(BaP)和镉(Cd2+)暴露对雄性食蚊鱼(Gambusia affinis)求偶行为的影响.设对照组和实验组,BaP暴露浓度为0、0.1、100 μg/L;Cd2+暴露浓度为0、5、500 nmol/L;分别暴露6和8周.暴露实验结束后,观察雄鱼与雌鱼配对(1∶1)的求偶行为,并作录像记录分析.结果显示,雄鱼在0.1和100 μg/L的BaP分别暴露6周后其对雌鱼的求偶行为开始明显降低,并随着暴露浓度的升高和时间的延长而呈现下降趋势;BaP高浓度组(100 μg/L)暴露8周后对雄鱼有严重的致死效应.暴露在5和500 nmol/L的Cd2+至8周后雄鱼求偶行为明显降低;雌鱼暴露在低浓度BaP和Cd2+中其对雄鱼的求偶行为无明显影响(P>0.05);但分别在高浓度100 μg/L BaP和500 nmol/L Cd2+中暴露后,雄鱼对雌鱼的求偶行为显著减少.结果表明,BaP和Cd2+暴露均可降低雄性食蚊鱼的求偶行为.

  17. Phytoplankton growth, dissipation, and succession in estuarine environments. Renewal proposal and annual summary report, August 1, 1977--July 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Seliger, H H

    1978-01-01

    The directions of the research program in understanding the dynamics of the natural phytoplankton populations of the Chesapeake Bay, the methodology, the statistical analysis, and the description of the system are parallel to the requirements for environmental impact studies. Results are reported for the following studies: development of instrumentation and the synoptic isopleth methodology for relating the dynamic distributions of natural phytoplankton populations to water circulation patterns; phytoplankton cage experiments for assessment of nutrient dynamics; sub-lethal concentrations and effects of polycyclic aromatic hydrocarbons; and studies on concentration and time kinetics of induction of liver aryl hydrocarbon hydroxylase system in Fundulus heteroclitus by benzopyrene and 3-methyl cholanthrene. (HLW)

  18. Profiling of Biomarkers for the Exposure of Polycyclic Aromatic Hydrocarbons: Lamin-A/C Isoform 3, Poly[ADP-ribose] Polymerase 1, and Mitochondria Copy Number Are Identified as Universal Biomarkers

    Directory of Open Access Journals (Sweden)

    Hwan-Young Kim

    2014-01-01

    Full Text Available This study investigated the profiling of polycyclic aromatic hydrocarbon- (PAH- induced genotoxicity in cell lines and zebrafish. Each type of cells displayed different proportionality of apoptosis. Mitochondrial DNA (mtDNA copy number was dramatically elevated after 5-day treatment of fluoranthene and pyrene. The notable deregulated proteins for PAHs exposure were displayed as follows: lamin-A/C isoform 3 and annexin A1 for benzopyrene; lamin-A/C isoform 3 and DNA topoisomerase 2-alpha for pentacene; poly[ADP-ribose] polymerase 1 (PARP-1 for fluoranthene; and talin-1 and DNA topoisomerase 2-alpha for pyrene. Among them, lamin-A/C isoform 3 and PARP-1 were further confirmed using mRNA and protein expression study. Obvious morphological abnormalities including curved backbone and cardiomegaly in zebrafish were observed in the 54 hpf with more than 400 nM of benzopyrene. In conclusion, the change of mitochondrial genome (increased mtDNA copy number was closely associated with PAH exposure in cell lines and mesenchymal stem cells. Lamin-A/C isoform 3, talin-1, and annexin A1 were identified as universal biomarkers for PAHs exposure. Zebrafish, specifically at embryo stage, showed suitable in vivo model for monitoring PAHs exposure to hematopoietic tissue and other organs.

  19. Efficient laser desorption ionization mass spectrometry of polycyclic aromatic hydrocarbons using excitation energy transfer from anthracene

    International Nuclear Information System (INIS)

    Highlights: ► Femtomolar detection of PAHs such as perylene and benzopyrene was achieved. ► Photoexcited anthracene molecules transferred their energy to PAHs. ► Electronically excited PAHs were then excited to be ions. ► Two-photon ionization process was necessary to complete the ionization process. ► The number of defect sites could be reduced by the annealing procedure. - Abstract: Polycyclic aromatic hydrocarbons (PAHs), such as perylene and benzopyrene, doped at amounts on the order of femtomol (∼10−15 mol) in anthracene crystals could be detected by laser desorption ionization mass spectrometry. Sensitivity was roughly 103 times higher than that of LDI method in our experimental conditions. It was revealed from the excitation power dependence of the peak intensity of PAHs on the mass spectra that two-photon excitation in one UV pulse was necessary to complete the ionization process. It was also clarified that the number of defect sites that trap excitons generated in anthracene crystals could be reduced by the annealing procedure, by which an efficient energy transfer between anthracene and PAHs became possible

  20. Cotinine and polycyclic aromatic hydrocarbons levels in the amniotic fluid and fetal cord at birth and in the urine from pregnant smokers.

    Directory of Open Access Journals (Sweden)

    Julia de Barros Machado

    Full Text Available Cigarette smoking during pregnancy has several impacts on fetal development, including teratogenic effects. The objective of this study was to assess whether the toxic substances (cotinine and polycyclic aromatic hydrocarbons found in pregnant smokers are transmitted to their fetuses. The outcomes were analyzed measuring cotinine and 1-hydroxypyrene in the amniotic fluid and maternal urine, benzopyrene and cotinine in the umbilical cord blood. Through a controlled cross-sectional design, 125 pregnant women were selected and classified according to their smoking status: 37 current smokers, 25 passive smokers and 63 non-smokers (controls. We performed high-performance liquid chromatography to measure substances' concentrations. A post-hoc Tukey's test was used to analyze the differences between the groups. All variables were significantly different between controls and smokers. The mean ratios between the concentration of cotinine in smokers compared to controls were as follows: 5.9 [2.5-13.5], p<0.001 in the urine; 25 [11.9-52.9], p<0.001 in the amniotic fluid; and 2.6 [1.0-6.8], p = 0.044 in the umbilical cord blood. The mean ratios of 1-hydroxypyrene concentration between smokers and controls were 7.3 [1.6-29.6], p = 0.003 in the urine and 1.3 [1.0-1.7], p = 0.012 in the amniotic fluid, and of benzopyrene in umbilical cord blood was 2.9 [1.7-4.7], p<0.001. There were no significant differences between controls and passive smokers. When comparing the three groups together, there were statistical differences between all variables. Thus, the fetuses of pregnant smokers are exposed to toxic and carcinogens substances. To our knowledge, this is the first study to measure 1-hydroxypyrene in the amniotic fluid and benzopyrene in umbilical cord blood by high-performance liquid chromatography when considering pregnant women in relation to smoking exposure only.

  1. BENZO[a]PYRENE METABOLITES EXAGGERATE DNA OXIDATIVE DAMAGE UPON THE INVOLVEMENT OF FREE RADICALS%苯并[a]比代谢产物在自由基参与下加速DNA的氧化损伤

    Institute of Scientific and Technical Information of China (English)

    罗云敬; GAO Da-yuan; WEI Hua-chen

    2003-01-01

    @@ Polycyclic aromatic hydrocarbons (PAHs),which constitute a major class of environmental pollu tants are posing a threat to human health. Benzopyrene,an index of PAH levels omnipresent in the everyday environment ,becomes toxic only when being metabolically and/or photo-activated,i. e. ,in the pres ence of UV light. Free radicals such as superoxide anions ('O2),hydrogen peroxide (H2O2),hydroxyl radicals ('OH) and singlet oxygen (1O2) are involved in carcinogenesis. Wei CE etc[1] studied the effects of different scavengers of active oxygen species (superoxide dismutase,catalase,mannitol and dimethyfu ran) on promoting B[a]P mutagenicity. Bryla P ete[2] investigated the roles of several ROS scavengers in the oxidation and binding of B[a]P to calf thymus DNA using the 32p-postlabeling assay.

  2. 湖南湘西腊肉品质调查与分析研究

    Institute of Scientific and Technical Information of China (English)

    罗青雯; 周辉; 刘成国; 娄爱华; 钟茹

    2015-01-01

    为了调查腌腊肉制品的卫生状况,对湘西地区农家、小作坊和工厂生产的腊肉进行感官评价,以及水分含量、盐分含量、亚硝酸盐残留、苯并芘残留及挥发性风味物质的检验。结果表明,所检测的42份样品中,亚硝酸盐残留量检出范围为0.68~12.21 mg/kg,均未超出国家限量标准(亚硝酸盐残留量≤30 mg/kg);苯并芘残留量检出范围为0.84~8.89μg/kg,苯并芘含量合格率为92.86%,感官评价结果优良。%To investigate the quality and hygiene of smoke-cured bacons,the bacon samples are collected from peasant household,small workshops,and bacon factory. The samples are analyzed the sensory scores,water content,salt content, nitrite residue and benzopyrene residue. The results indicate that in all 42 tested samples,nitrite residue is in the range of 0.68~12.21 mg/kg,which doesn't exceed the GB(nitrite residue≤30 mg/kg),the benzopyrene residue is in the range of 0.84~8.89μg/kg,the qualified rate is 92.86%,the senior grade of freshness is highly acceptable.

  3. Applications of Fiberoptics-Based Nanosensors to Drug Discovery

    Science.gov (United States)

    Vo-Dinh, Tuan; Scaffidi, Jonathan; Gregas, Molly; Zhang, Yan; Seewaldt, Victoria

    2013-01-01

    Background Fiber-optic nanosensors are fabricated by heating and pulling optical fibers to yield sub-micron diameter tips, and have been used for in vitro analysis of individual living mammalian cells. Immobilization of bioreceptors (e.g., antibodies, peptides, DNA, etc) selective to target analyte molecules of interest provides molecular specificity. Excitation light can be launched into the fiber, and the resulting evanescent field at the tip of the nanofiber can be used to excite target molecules bound to the bioreceptor molecules. The fluorescence or surface-enhanced Raman scattering produced by the analyte molecules is detected using an ultra-sensitive photodetector. Objective This article provides an overview of the development and application of fiber-optic nanosensors for drug discovery. Conclusions The nanosensors provide minimally invasive tools to probe sub-cellular compartments inside single living cells for health effect studies (e.g., detection of benzopyrene adducts) and medical applications (e.g., monitoring of apoptosis in cells treated with anti-cancer drugs). PMID:23496274

  4. Development of a Thermoplastic Magnesia Carbon Brick——"A Cold Process Flexible System"

    Institute of Scientific and Technical Information of China (English)

    R.Mishra; S.Mukhopadhyay

    2006-01-01

    Conventional resin bonded MgO-C bricks, which are manufactured via cold mixing process, harden and attain brittleness during carbonization of resin due to the formation of isotropic glassy carbon. They do not exhibit thermo-plasticity, which can facilitate the release of huge amount of stresses generated during preheating or in operation. On the contrary, pitch bonded MgO-C bricks, show better pyro-plasticity due to formation of an anisotropic and graphitized coke structure during carbonization of pitch. Hence, pitch bonded bricks show a superior structural spalling resistance in comparison to resin-bonded bricks. One of the drawbacks of pitch-bonded bricks is that the manufacturing requires a hot mixing process and hot pressing facility. This paper describes how a combination of above two processes was optimized to make a MgO-C brick via cold process. These bricks exhibit a low Modulus of Elasticity and thereby facilitate release of stresses during operation. Normal coal tar pitch is considered as an environmental hazard due to the presence of polyaromatic hydrocarbons like benzopyrene B [ a ] P. So, a special binder with a low B [ a ] P was selected, which is eco-friendly in nature. Such bricks were made in our plant in China and supplied to an integrated steel plant in Europe for their ladle. The bricks supplied have given encouraging life.

  5. Pollution release nad transfer register as an effective tool for monitoring of ecological safety of soil in Areas of oil production

    International Nuclear Information System (INIS)

    Full text : The oil production process is accompanied by an increased level of radiation. The main sources of radiation hazard to oil and gas fields are the sludge of produced waters, radioactive salts sediments on equipment, previously buried sludge and salt. Radioactive salts and sludge are deposited in the oil and gas equipment. Experiments were carried out in the areas of oil production on the 3 main types of pollutants, which are : petroleum derivatives, particularly benzopyrene, which has high carcinogenic activity; radiation due to the increased levels of radionuclides in the sludge of produced water; heavy metals, as the oil production process is accompanied by input of large amounts of heavy metals. The scientific researche play the main role in analyzing the PRTR data. Finally it would be worth to mentionthe national legislation regulated the radiation safety in Azerbaijan. This law includes requirements for ensuring radiation safety in industrial entities and environmental norms protecting the safety of employees and populations in areas potentially affected by the use of radioactive sources

  6. Chemically induced DNA hypomethylation in breast carcinoma cells detected by the amplification of intermethylated sites

    International Nuclear Information System (INIS)

    Compromised patterns of gene expression result in genomic instability, altered patterns of gene expression and tumour formation. Specifically, aberrant DNA hypermethylation in gene promoter regions leads to gene silencing, whereas global hypomethylation events can result in chromosomal instability and oncogene activation. Potential links exist between environmental agents and DNA methylation, but the destabilizing effects of environmental exposures on the DNA methylation machinery are not understood within the context of breast cancer aetiology. We assessed genome-wide changes in methylation patterns using a unique methylation profiling technique called amplification of intermethylated sites (AIMS). This method generates easily readable fingerprints that represent the investigated cell line's methylation profile, based on the differential cleavage of DNA with methylation-specific isoschisomeric restriction endonucleases. We validated this approach by demonstrating both unique and reoccurring sites of genomic hypomethylation in four breast carcinoma cell lines treated with the cytosine analogue 5-azacytidine. Comparison of treated with control samples revealed individual bands that exhibited methylation changes, and these bands were excized and cloned, and the precise genomic location individually identified. In most cases, these regions of hypomethylation coincided with susceptible target regions previously associated with chromosome breakage, rearrangement and gene amplification. Similarly, we observed that acute benzopyrene exposure is associated with altered methylation patterns in these cell lines. These results reinforce the link between environmental exposures, DNA methylation and breast cancer, and support a role for AIMS as a rapid, affordable screening method to identify environmentally induced DNA methylation changes that occur in tumourigenesis

  7. Some carcinogenic polycyclic aromatic hydrocarbons by photoacoustic spectroscopy

    Science.gov (United States)

    Garg, R. K.; Kumar, Pardeep; Ram, R. S.; Zaidi, Zahid H.

    1999-12-01

    Polycyclic aromatic hydrocarbons (PAHs) have attracted spectroscopists, astrophysicts and environmentalist because of their importance in our day to day life. It is well known that epoxides are produced during the metabolism of PAHs and have the requisite chemical reactivity to qualify them for the role as an ultimate carcinogenic form of PAHs. Several carcinogenic PAHs such as 3.4-benzopyrene, 1.2,3.4-dibenzopyrene, 3.4,9.10- dibenzopyrene etc. are found to be present in tobacco smoke and among air pollutants. Although PAH molecules are being studied for last several years by using conventional spectroscopy but no systematic attempt has been made to study non-radiative transitions. In our laboratory, we have studied many PAH molecules by a non-destructive technique with unique capability and sensitivity, known as Photoacoustic (PA) spectroscopy. PA spectroscopy is an analytical and research tool to get information about non-radiative transitions and singlet-triplet electronic transitions, where the conventional spectroscopic technique fails. The study of electronic transitions of some carcinogenic molecules are reported using PA and optical absorption spectra in boric acid glass in the region 250 - 400 nm. The electronic transitions of these molecules observed experimentally, have been interpreted using the optimized geometries and CNDO/S-CI method. A good agreement is found between the experimental and calculated results. Assignments of observed electronic transitions are made on the basis of singlet-triplet electronic transitions. Vibrations attached to these electronic transitions are attributed to the ground state vibrational modes.

  8. Effect of Water Washing on Hydrocarbon Compositions of Petropleum Sandstone Reservoir Rocks in Tarim Basin,NW China

    Institute of Scientific and Technical Information of China (English)

    张敏; 张俊

    2000-01-01

    Gross compositions and distribution of saturated and aromatic hydrocarbons in Carboniferous sandstone reservoire rocks in oil and water zones for Tzhong-10 well of the Zhongyang Uplift in the Tarim Basin were studied in dteail by means of Rock-Eval Pyrolysis,thin-chromatograph-flame ionization detection(TLC-FID),gas chromatography,gas chromatography-mass spectrometry.The results suggest that the gross composition of reservoir hydrocarbons between the oil zone and the water zone show significant differences,Water wahing has a dramatic effect on saturated hydrocarbon blomarkers,especially drimane series compounds,Drimane series compounds in the water zone have been depleted completely.However,the contents of tricyclic iterpanes and pentacyclic triterpanes tend to decrease slightly,but the water-zone reservoir hydrocarbons contian a large amount of gammacerane.This suggests that gammacerane be more resistant to water washing than diterpanes and homohopanes.The contents of pregnane,homopregrane,diasteranes relastively decrease as a result of water washing.Water washing has a noticeable effect on polycyclic aromatic hydrocarbon compounds,especially aromatic sulfur compounds,and the contents of dibenzothiophene series compounds and benzonaplyiothipophene decrease significantly as a result of water washing.However,the conterts of bicyclic and tricyclic aromatic hydrocarbons decrase slightly and those of tetracyclic and pentacyclic aromatic hydrocarbons,especially benzofluoranthene and benzopyrenes,increase markedly owing to adecrease in light aromatie hydrocarbons as a result of water washing.

  9. Effects of cigarette smoke composition on respiratory system%香烟烟雾成分对呼吸系统的影响

    Institute of Scientific and Technical Information of China (English)

    马铮; 平芬; 曹磊; 苏力; 马坤; 梁会朋

    2015-01-01

    Cigarette smoke contains a lot of harmful substances.For the human respiratory system,the most harmful substances include nicotine,benzopyrene,hydrogen cyanide,tobacco tar,carbon monoxide,nitric,and other harmful substances such as cadmium,benzidine,vinyl chloride and so on.The effects of some cigarette smoke composition on the respiratory system are reviewed in this paper as follows.%香烟烟雾含有大量的有害物质,其中对人体呼吸系统危害最大的物质包括烟碱(尼古丁)、苯并芘、氰化氢、烟焦油、一氧化碳和一氧化氮及其他有害物质金属镉、联苯胺、氯乙烯等。本文将部分香烟烟雾成分对呼吸系统的影响综述如下。

  10. Molecular fossils and sources of Cambrian heavy oil of Well Tadong-2 in theTarim Basin, Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    TANG Youjun; ZAN Ling

    2009-01-01

    Research on the molecular fossil characteristics of heavy oil from Well Tadong-2 is of great importance to constrain the source of marine crude oils in the Tarim Basin, Xinjiang, China. The authors synthetically applied the isotope mass spectrograph, chromatography and chromatography-mass spectrography to the studies of molecular fossil characteristics of heavy oil from Well Tadong-2 in the Tarim Basin, and the results obtained revealed that heavy oil from Well Tadong-2 is characterized by high gammacerane, high C28 sterane, low rearranged sterane and high C27-triaromatic steroid, these characteristics are similar to those of Cambrian-Lower Ordovician source rocks, demonstrating that Cambrian crude oils came from Cambrian-Lower Ordovician source rocks; condensed compounds (fluoranthene, pyrene, benzo[a]anthracene, bow, benzo fluoranthene, benzopyrene) of high abundance were detected in heavy oil from Well Tadong-2, and the carbon isotopic values of whole oil are evidently heavy, all the above characteristics revealed that hydrocarbons in the crude oils became densified in response to thermal alteration.

  11. Ecological situation at the coke plant of the Nizhnii Tagil Integrated Iron and Steel Works (according to data from an expert commission of Gosstroi USSR)

    International Nuclear Information System (INIS)

    A main source of pollution is the Nizhnii Tagil Integrated Iron and Steel Works (NTMK), whose share in the total emissions of harmful substances is very significant. Thus, in 1987 the mean annual dust content in the atmosphere of the city surpassed the maximum admissible concentrations 1.3 times, phenol 2 times, ammonia 2.5 times, benzopyrene 6 times. In 1988 an even higher content of harmful substances was noted. Reconstruction of the coke plant now underway has been called upon to ensure a significant improvement in the ecological conditions together with an overall increase in its technical level. Restoration of the existing capacity of the coke batteries at domestic coke plants is being accomplished according to two variants: first - relining of the batteries with retention of the existing dimensions or with a slight very limited increase, with modernization of the designs of the ovens and chemical departments, and also machines and equipment (technical refitting); second - withdrawal from operation of the existing batteries and construction of new higher capacity coke batteries in the plant area (reconstruction). From the standpoint of ecology and economy of capital investment it would be more expedient to restore capacity at NTMK according to the first variant. However, restoration here is being carried out according to the second variant with construction of coke batteries 9 and 10 in a new area with dry coke quenching. There are plans to decommission batteries 1-4. An analysis is given of the sources of pollution from the coke plant and measures are defined to reduce pollutants

  12. Synthesis and characterization of electroactive films based on benzo(a)pyrene

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Michal; Yu Kai [Process Chemistry Centre, c/o Laboratory of Analytical Chemistry, Abo Akademi University, Biskopsgatan 8, FI-20500 Abo/Turku (Finland); Kvarnstroem, Carita, E-mail: carita.kvarnstrom@utu.f [Turku University Centre for Materials and Surfaces, c/o Laboratory of Materials Chemistry and Chemical Analysis, Department of Chemistry, University of Turku, Vatselankatu 2, FI-20014 Turku (Finland); Ivaska, Ari, E-mail: ari.ivaska@abo.f [Process Chemistry Centre, c/o Laboratory of Analytical Chemistry, Abo Akademi University, Biskopsgatan 8, FI-20500 Abo/Turku (Finland)

    2011-04-01

    The polycyclic aromatic hydrocarbons (PAHs) are a group of compounds that might have practical applications due to their graphene-like properties. Derivatized PAHs can self-assemble in liquid crystal form. The chemical synthesis of large size PAHs can however be complicated and problematic. Electrochemical synthesis of PAHs molecules was studied in this work by cyclic voltammetry. Benzo(a)pyrene was used as the monomer. The resulting electroactive films consist of different PAHs in both size and symmetry. We call this mixture poly(benzopyrene) (PBP). The synthesis conditions of PBP were optimized to obtain thick and electrochemically stable films. The best film quality was achieved by potential scanning in propylene carbonate at low scan rate resulting in continues polymer growth during 10 scans giving approx. a 1 {mu}m thick PBP film. During p- and n-doping studies the reduction and oxidation peaks were observed at 1.0 V and -1.6 V, respectively, with an electrochemical band gap of approx. 2.6 eV. The in situ UV-vis characterization of the PBP films was made by applying a constant potential with increasing steps. The optical band gap was approx. 2.5 eV and the absorption maximum was observed at ca. 420 nm. During p- and n-doping new induced bands were formed in the range 575-600 nm. UV-vis spectroscopy indicate that PBP mainly consist of units consisting of more than 40 carbon atoms and large number of {pi}-electrons.

  13. Nicotine overrides DNA damage-induced G1/S restriction in lung cells.

    Directory of Open Access Journals (Sweden)

    Takashi Nishioka

    Full Text Available As an addictive substance, nicotine has been suggested to facilitate pro-survival activities (such as anchorage-independent growth or angiogenesis and the establishment of drug resistance to anticancer therapy. Tobacco smoking consists of a variety of carcinogens [such as benzopyrene (BP and nitrosamine derivatives] that are able to cause DNA double strand breaks. However, the effect of nicotine on DNA damage-induced checkpoint response induced by genotoxins remains unknown. In this study, we investigated the events occurred during G(1 arrest induced by γ-radiation or BP in nicotine-treated murine or human lung epithelial cells. DNA synthesis was rapidly inhibited after exposure to γ-radiation or BP treatment, accompanied with the activation of DNA damage checkpoint. When these cells were co-treated with nicotine, the growth restriction was compromised, manifested by upregulation of cyclin D and A, and attenuation of Chk2 phosphorylation. Knockdown of cyclin D or Chk2 by the siRNAs blocked nicotine-mediated effect on DNA damage checkpoint activation. However, nicotine treatment appeared to play no role in nocodazole-induced mitotic checkpoint activation. Overall, our study presented a novel observation, in which nicotine is able to override DNA damage checkpoint activated by tobacco-related carcinogen BP or γ-irradiation. The results not only indicates the potentially important role of nicotine in facilitating the establishment of genetic instability to promote lung tumorigenesis, but also warrants a dismal prognosis for cancer patients who are smokers, heavily exposed second-hand smokers or nicotine users.

  14. CHARACTERIZATION OF HEXANE SOLUBLE OILS FROM LIQUEFACTION OF TWO BITUMINOUS COALS%两种烟煤的液化及液化油的组成特征研究

    Institute of Scientific and Technical Information of China (English)

    朱继升; LawrenceP.Norcio

    2001-01-01

    Two high-volatile subbituminous coals, DECS-6 of US and Yanzhou coal of China, were liquefied or co-liquefied with HDPE or PVC at 400?℃, 30?min under 7?MPa hydrogen. The results show that Yanzhou coal is easier to be liquefied or co-liquefied than DECS-6 coal under the experimental conditions used and the hexane-soluble oil from Yanzhou coal has more low boiling point fractions than that from DECS-6 coal. The aromatics in hexane soluble oils mainly consist of alkylbeneze, alkylnaphthalene, phenanthrene-,pyrene-, chrysene-, and benzopyrene- compounds, the polars mainly compose of compounds containing O, S and N etc.%在400 ℃、30 min、7 MPa冷氢压条件下两种煤液化结果表明,兖州煤比DECS-6(美国煤)煤更容易液化或共液化,这可能与兖州煤硫含量比较高有关,但DECS-6煤的油收率要高于兖州煤,表明EDCS-6煤容易裂解生成小分子化合物。同种煤液化油的沸点分布特征基本一致。UV(紫外光谱)特征表明,液化油中单环芳烃主要为烷基取代苯类化合物,二环芳烃组分主要是烷基取代萘类化合物,三环芳烃主要为渺位缩合的菲类化合物,四环芳烃主要为芘、屈艹类化合物,五环芳烃以苯并芘类化合物为主,而极性化合物可归属为含O、S、N的极性芳香化合物。

  15. Genistein, isoflavonoids in soybeans, prevents the formation of excess radiation-induced centrosomes via p21 up-regulation

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, Mikio; Kato, Akihiro [Department of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Yoshida-konoe, Sakyo, Kyoto 606-8501 (Japan); Habu, Toshiyuki [Department of Radiation System Biology, Radiation Biology Center, Kyoto University, Kyoto 606-8501 (Japan); Komatsu, Kenshi, E-mail: komatsu@house.rbc.kyoto-u.ac.jp [Department of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Yoshida-konoe, Sakyo, Kyoto 606-8501 (Japan)

    2011-11-01

    The centrosome is a cytoplasmic organelle which duplicates once during each cell cycle, and the presence of excess centrosomes promote chromosome instability through chromosome missegregation following cytokinesis. Ionizing radiation (IR) can induce extra centrosomes by permitting the continuation of CDK2/Cyclin-A/E-mediated centrosome duplication when cells are arrested in the cell cycle after irradiation. The work described here shows that, in addition to IR, extra centrosomes were induced in human U2OS and mouse NIH3T3 cells after treatment with agents which include DNA adduct-forming chemicals: benzopyrene (BP), 4-nitroquinoline 1-oxide (4NQO), a DNA cross linker: cis-diamminedichloro-platinum (cisplatin), topoisomerase inhibitors: camptothecin, etoposide, genistein, and ultra-violet light (UV). These agents were divided into two categories with respect to the regulation of p21, which is an inhibitor of CDK2/Cyclin-A/E: specifically, p21 was up-regulated by an IR exposure and treatment with topoisomerase inhibitors. However, UV, BP, 4NQO and cisplatin down-regulated p21 below basal levels. When cells were irradiated with IR in combination with all of these agents, except genistein, enhanced induction of extra centrosomes was observed, regardless of the nature of p21 expression. Genistein significantly suppressed the frequency of IR-induced extra centrosomes in a dose-dependent manner, and 20 {mu}g/ml of genistein reduced this frequency to 66%. Consistent with this, genistein substantially up-regulated p21 expression over the induction caused by IR alone, while other agents down-regulated or marginally affected this. This suggests the inhibitory effect of genistein on the induction of extra centrosomes occurs through the inactivation of CDK2/Cyclin-A/E via p21 up-regulation. This hypothesis is supported by the observation that p21 knockdown with siRNA reduced the activity of CDK2/Cyclin-A/E and restored the enhanced effect of a combined treatment with genistein

  16. 煤的基本化工过程与污染特征分析%Basic coal chemical processes and their pollution characteristics

    Institute of Scientific and Technical Information of China (English)

    韦朝海; 廖建波; 胡芸

    2016-01-01

    main pollutants produced by coal chemical process were introduced from the coal properties,the process requirements,and the technology features. The source and composition of the “three wastes” were selectively analyzed from the processes of coal-to-coke and coal-to-gas. Among them,the waste gas came from the incompletely carbonized pulverized coal in the chemical conversion process,the precipitated matters including volatile matter,tar fog and fly ash,the leaked raw gas,as well as CO,CO2 and NO2 generated by burning coke on contact with air. The wastewater included dedusting wastewater,surplus aqueous ammonia,phenol and cyanogens wastewater,desulfurization liquid and the water sealing gas. The waste residue included dust,coal dust,acid tar,tar slag and sludge. The gas phase pollutants from coal chemical process mainly included oxycarbide,oxysulphide,ammonia gas,volatile phenol,benzene,benzopyrene,CO,CH4 and small molecule hydrocarbons. The liquid phase pollutants contained not only ammonia,cyanide,sulphide, benzene,phenol and oil,but also a lot of benzopyrene,naphthalene and other PAHs,and heterocyclic aromatic hydrocarbons including pyridine,carbazole,biphenyl,terphenyl,etc. The pollution characteristics showed wide distribution,complex components,high concentration,coexistence of multiphase mediums with high environment risk. The typical characteristics of the coal chemical wastewater were high concentration/salinity,high pollution (multicomponent),toxic and refractory. The clarification of the relationship between the coal chemical process and pollution characteristics needed researchers to deepen the comprehensive understanding for the basic coal properties,the principles of conversion,purification and application. Therefore,the control technology and strategy should be based on the deep understanding for the chain of resource- product-economy-environment- society and the effective integration system,and the strategic design and logic innovation should be

  17. Relationship between Appearance Quanlity and Deliveres of Main Harmful Compounds in Mainstream Smoke from Flue-cured Tobacco Leaves%初烤烟叶外观质量与其主流烟气有害成分释放量关系研究

    Institute of Scientific and Technical Information of China (English)

    付秋娟; 刘加红; 张怀宝; 张忠锋; 侯小东; 郑成鹏; 杜咏梅; 赵友根

    2015-01-01

    218 samples of flue-cured tobacco leaves of representative area in China were collected to investigate relationship between major appearance characteristic and deliveries of harmful compounds in mainstream smoke of flue-cured tobacco leaves.Variance analysis was used to study the difference of deliveries of tar,nicotine and seven harmful ingredients (carbon monoxide,benzopyrene,phenol,hydrogen cyanide,NNK,ammonia,crotonaldehyde) in mainstream smoke between different characteristic of maturity,color,body,oil,leaf structure,color intensity of flue-cured tobacco leaves.Results showed that color,body,leaf structure of tobacco leaves had significant influence on deliveries of harmful compounds in mainstream smoke,but that of the maturity,oil and color intensity had a little influence .The deliveries of tar,nicotine,phenol,ammonia,hydrogen cyanide in mainstream smoke of orange tobacco leaves were greater than that of lemon tobacco leaves.In general,the deliveries of nicotine,phenol in mainstream smoke of fleshy tobacco leaves were larger than that of less thin tobacco leaves.With the tobacco leaves structure tending to be loose,The deliveries of tar,nicotine and phenol in mainstream smoke were significant decrease,and the deliveries of crotonaldehyde were significant increase.%为明确初烤烟叶主要外观质量与其主流烟气有害成分释放量的关系,收集我国代表产地初烤烟叶样品218份,应用方差分析,研究了不同成熟度、颜色、身份、油分、叶片结构、色度特征的初烤烟叶主流烟气烟碱、焦油及7项有害成分(一氧化碳、苯并芘、苯酚、氰化氢、NNK、氨、巴豆醛)释放量的差异.结果表明,烟叶颜色、身份、叶片结构对主流烟气有害成分释放量的影响较大,成熟度、油分、色度对主流烟气有害成分释放量的影响较小;橘黄烟叶主流烟气焦油、烟碱、苯酚、氨、氰化氢释放量显著或极显著大于柠檬黄烟叶;身份较厚的烟叶

  18. Distribution and source apportionment of polycyclic aromatic hydrocarbons in surface soils in Shanghai%上海市表层土壤中多环芳烃的分布特征与源解析

    Institute of Scientific and Technical Information of China (English)

    杜芳芳; 杨毅; 刘敏; 陆敏; 于英鹏; 郑鑫; 刘营

    2014-01-01

    应用气相色谱-质谱联用仪(GC-MS)对上海市80个表层土壤样品中16种优控多环芳烃的浓度进行了测定,分析了上海市土壤中PAHs的含量分布特征,并利用同分异构体比值、主成分分析方法对表层土壤中的PAHs进行了源解析.结果表明,80个样点PAHs的含量在0.12~24.5μg/g之间,呈现出郊区>市区>农村的梯度变化,市区内不同功能区采样点呈现出交通区>文教区>公园绿地>商业区>住宅区的梯度变化. PAHs组成以4环和5环为主,平均含量分别占∑PAHs的49.2%和27.0%,其次为3环和6环,分别占∑PAHs的14.8%和6.6%,最低为2环PAHs,仅占2.4%,单体PAHs化合物以荧蒽、芘、苯并芘为主.源解析表明,表层土壤中PAHs的主要来源是燃烧源,主要是石油燃烧.%The concentrations of sixteen priority polycyclic aromatic hydrocarbons in 80 topsoil samples in Shanghai were determined by GC-MS. The distribution pattern was discussed, and source apportionment of PAHs in surface soil was conducted by the isomer ratio and principal component analysis. Results showed that the concentrations of PAHs ranged between 0.12μg/gand 24.5μg/g, presenting gradient changes of suburb>urban> rural and traffic area>cultural and educational area>park greenbelt>business district>residential in different functional areas in the city. Dominant compounds were 4rings and 5rings PAHs, which accounted for 49.2% and 27.0%, followed by 3and 6rings, which accounted for 14.8% and 6.6% of the total PAH concentrations, respectively. The lowest was the 2rings PAHs, which only accounted for 2.4% of the total PAH concentrations. In addition, fluoranthene, pyrene and benzopyrene were dominant PAH compounds. Source apportionment indicated that the PAHs originated mainly from burning, mainly oil burning.

  19. Uncertainties under emergency conditions in Hiroshima and Nagasaki in 1945 and Bikini accident in 1954

    Energy Technology Data Exchange (ETDEWEB)

    Nishiwaki, Y. [Universitaet Wien, Institut fuer Medizinische Physik, Vienna (Austria); Kawai, H. [Atomic Energy Research Institute of Kinki Univ., Osaka (Japan); Shono, N. [Hiroshima Jogakuin Univ., Hiroshima (Japan); Fujita, S. [Radiation Effects Research Foundation, Department of Statistics, Hiroshima (Japan); Matsuoka, H. [Japan Atomic Energy Research Institute, Earth Simulator Research and Development Center, Tokyo (Japan); Fujiwara, S. [Japan Nuclear Cycle Development Institute, Ibaraki (Japan); Hosoda, T. [Chiyoda Technol Corporation, Tokyo (Japan)

    2000-05-01

    In exploding an atomic bomb, in addition to ionizing radiation, strong non-ionizing radiation, such as infrared, ultraviolet light, visible light, electromagnetic pulse radiation, as well as heat and shock waves are produced. The survivors and those who visited Hiroshima immediately after the atomic bombing could have been subjected to a number of other possible noxious effects in addition to atomic radiation. Hospitals, laboratories, drugstores, pharmaceutical works, storehouses of chemicals, factories, etc. that were situated close to the hypocenter were all completely destroyed and various mutagenic, carcinogenic or teratogenic substances must have been released, many doctors, nurses and chemists were killed. There was no medical care and no food in the region of high dose exposure and the drinking water was contaminated. There would have been various possibilities of infection. Mental stress would also have been much higher in the survivors closer to the hypocenter. It is confusing which factor played a dominant role. In addition, there would be problems in accurately identifying the position of the exposed persons at the time of the atomic bombing and also in estimating the shielding factors. There may be considerable uncertainty in human memory under such conditions. It is also possible that there could have been a large storage of gasoline to be used for transportation of the army corps in Hiroshima. Therefore there is a possibility that various toxic substances, mutagenic or carcinogenic agents such as benzopyrene and other radiomimetic substances, chemical weapons (Yperit, Lewisite, etc.) could have been released from various facilities which were destroyed at the time of the atomic bombing. After the German surrender, in May 1945, it was reported in June, in Japan, that the USA might attempt landing on Japan mainland, and that they might be planning massive use of chemical weapons all over Japan on that occasion. Preparing for such case chemical officers

  20. Uncertainties under emergency conditions in Hiroshima and Nagasaki in 1945 and Bikini accident in 1954

    International Nuclear Information System (INIS)

    In exploding an atomic bomb, in addition to ionizing radiation, strong non-ionizing radiation, such as infrared, ultraviolet light, visible light, electromagnetic pulse radiation, as well as heat and shock waves are produced. The survivors and those who visited Hiroshima immediately after the atomic bombing could have been subjected to a number of other possible noxious effects in addition to atomic radiation. Hospitals, laboratories, drugstores, pharmaceutical works, storehouses of chemicals, factories, etc. that were situated close to the hypocenter were all completely destroyed and various mutagenic, carcinogenic or teratogenic substances must have been released, many doctors, nurses and chemists were killed. There was no medical care and no food in the region of high dose exposure and the drinking water was contaminated. There would have been various possibilities of infection. Mental stress would also have been much higher in the survivors closer to the hypocenter. It is confusing which factor played a dominant role. In addition, there would be problems in accurately identifying the position of the exposed persons at the time of the atomic bombing and also in estimating the shielding factors. There may be considerable uncertainty in human memory under such conditions. It is also possible that there could have been a large storage of gasoline to be used for transportation of the army corps in Hiroshima. Therefore there is a possibility that various toxic substances, mutagenic or carcinogenic agents such as benzopyrene and other radiomimetic substances, chemical weapons (Yperit, Lewisite, etc.) could have been released from various facilities which were destroyed at the time of the atomic bombing. After the German surrender, in May 1945, it was reported in June, in Japan, that the USA might attempt landing on Japan mainland, and that they might be planning massive use of chemical weapons all over Japan on that occasion. Preparing for such case chemical officers

  1. 介孔氧化铝选择性吸附烟气中低分子醛酮化合物的研究%Study on the selective adsorption of low-molecular aldehydes and ketones from cigarette smoke using mesoporous alumina

    Institute of Scientific and Technical Information of China (English)

    冯守爱; 黄泰松; 邹克兴; 李志华; 周俊; 韦康; 白家峰

    2013-01-01

    To eliminate the low-molecular aldehydes and ketones in mainstream cigarette smoke and study the effect of mesoporous alumina on the adsorption of harmful components from smoke,mesoporous alumina particles with different microstructure was separately introduced into filter tip and the corresponding influences on the content of the low-molecular aldehydes and ketones in mainstream cigarette smoke were studied.The results showed that mesoporous alumina could effectively eliminate the low-molecular aldehydes and ketones from the mainstream cigarette smoke and the elimination efficiency was closely associated with the pore size of mesoporous alumina.The further study on the adsorption of phenol and benzopyrene from cigarette smoke using mesoporous alumina revealed that the preferential adsorption of low-molecular aldehydes and ketones was associat ed with the selective adsorption of polar molecules on mesoporous alumina and the low melting and boiling points of these aldehydes and ketones.In summary,the commendable adsorption performance of mesoporous alumina should be related to its abundant mesoporous structure,the electrostatic attraction on the interface,nanometer pore space confinement and the low melting and boiling points of low-molecular aldehydes and ketones.The analysis result about the three indicators of mainstream cigarette smoke showed that mesoporous alumina had no obvious influence on the content of tar and nicotine in smoke.%为降低卷烟烟气中有害成分低分子醛酮化合物的含量和研究介孔材料在烟气减害中的作用及其机制,将不同微结构特征的介孔氧化铝分别添加到卷烟嘴棒中,研究其对主流烟气中8种低分子醛酮化合物含量的影响.结果显示,介孔氧化铝对低分子醛酮有明显的吸附作用,而且脱除效果与介孔氧化铝的孔径密切相关,这与介孔氧化铝的纳米限域效应有关.通过进一步研究介孔氧化铝对烟气中苯酚和苯并(α)芘的吸附作

  2. On the issue of higher human sensitivity to carcinogenic substances in early childhood; Zur Frage einer hoeheren Empfindlichkeit von Kindern gegenueber krebserzeugenden Stoffen

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, K. [comp.

    1998-09-01

    Age-dependent carcinogenesis in humans has been proven with high probability for a number of substances investigated within one or several model systems. Sometimes, very high tumor incidence after short exposure time was observed. Extreme differences were found in some models. (A) Vinyl chloride, Maltoni et al.,1981: 6000 ppm, hepatic angiosarcoma incidence: - Exposure for 4 weeks, from day 1: 40.5 %, - exposure for 4 weeks, from week 13: 0%, - exposure for 52 weeks, from week 13: 22%. Hepatoma incidence: - Exposure for 4 weeks, from day 1: 47.6%, exposure for 4 weeks, from week 13: 0%, exposure for 52 weeks, from week 13: 1.7%. (B) Diethyl nitrosamine, Dyroff et al., 1986: (DEN + phenobarbital), hepatic carcinoma after exposure of rats for 6 weeks: - as from 4 weeks of age: 100% incidence, - as from 8 weeks of age: 0% incidence. (C) Benzopyrene, Vesselinovitch et al., 1975: Hepatic tumor incidence after single, parenteral administration to rats: - at day 1: males: 81%, females: 18%, - at day 42: males: 9%, females: 0%. As is shown by the study on vinyl chloride by Maltoni et al., the same exposure concentration may lead to higher tumor incidence in young animals after short exposure times than it does in long-term experiments with adult animals. Genetic toxicity was detected for all substances, except for saccharin. So it can be assumed that the mechanism of carcinogenesis has an essential influence on the age-dependence. This conclusion agrees well with mechanistic approaches. (orig./CB) [German] Fuer eine Reihe von Schadstoffen ist eine Altersabhaengigkeit der Kanzerogenese mit hoher Wahrscheinlichkeit in einem oder mehreren Modellsystemen gezeigt worden. Dabei wurden zum Teil bereits nach kurzer Expositionszeit sehr hohe Tumorausbeuten erzielt. Extreme Unterschiede wurden in folgenden Modellen beobachtet. (A) Vinylchlorid, Maltoni et al., 1981: 6000 ppm, Inzidenz Leberangiosarkome: - Exposition ueber 4 Wochen ab Tag 1: 40,5%, - Exposition ueber 4 Wochen ab 13

  3. Molecular biology of the stress response in the early embryo and its stem cells.

    Science.gov (United States)

    Puscheck, Elizabeth E; Awonuga, Awoniyi O; Yang, Yu; Jiang, Zhongliang; Rappolee, Daniel A

    2015-01-01

    Stress is normal during early embryogenesis and transient, elevated stress is commonplace. Stress in the milieu of the peri-implantation embryo is a summation of maternal hormones, and other elements of the maternal milieu, that signal preparedness for development and implantation. Examples discussed here are leptin, adrenaline, cortisol, and progesterone. These hormones signal maternal nutritional status and provide energy, but also signal stress that diverts maternal and embryonic energy from an optimal embryonic developmental trajectory. These hormones communicate endocrine maternal effects and local embryonic effects although signaling mechanisms are not well understood. Other in vivo stresses affect the embryo such as local infection and inflammation, hypoxia, environmental toxins such as benzopyrene, dioxin, or metals, heat shock, and hyperosmotic stress due to dehydration or diabetes. In vitro, stresses include shear during handling, improper culture media and oxygen levels, cryopreservation, and manipulations of the embryo to introduce sperm or mitochondria. We define stress as any stimulus that slows stem cell accumulation or diminishes the ability of cells to produce normal and sufficient parenchymal products upon differentiation. Thus stress deflects downwards the normal trajectories of development, growth and differentiation. Typically stress is inversely proportional to embryonic developmental and proliferative rates, but can be proportional to induction of differentiation of stem cells in the peri-implantation embryo. When modeling stress it is most interesting to produce a 'runting model' where stress exposures slow accumulation but do not create excessive apoptosis or morbidity. Windows of stress sensitivity may occur when major new embryonic developmental programs require large amounts of energy and are exacerbated if nutritional flow decreases and removes energy from the normal developmental programs and stress responses. These windows correspond

  4. 沈阳市城郊土壤有机污染特征%Characteristics of soil organic pollution in Shenyang suburbs of Liaoning Province, Northeast China

    Institute of Scientific and Technical Information of China (English)

    崔健; 都基众; 杨泽; 马宏伟; 李霄

    2011-01-01

    对沈阳市城郊土壤中35种有机污染物进行了检测,分析了土壤有机污染检出特征和空间分布特征.沈阳市城郊土壤共检出了15种有机污染物;苯并(a)芘、六氯苯、滴滴涕和六六六的变异系数均大于l,其污染物浓度局部富集程度高,含量起伏变化大,土壤有机污染呈现“一多三少”的现象,即全区检出有机污染物的采样点多,检出的有机污染物种类较少,有机污染物含量少,且无超标点.受土壤包气带岩性影响,城郊土壤垂向上有机污染规律明显.土壤区域有机污染分布特征与城市土地利用功能一致性较高.分析了各类有机污染物含量和分布特征的主要影响因素,对防治城市土壤污染,进而保障居民的食品安全和饮水安全具有重要意义.%Based on the survey of 35 organic pollutants in the soils of Shenyang suburbs, this paper studied the detection characteristics of the pollutants and their spatial distribution characteristics. Fifteen of the 35 organic pollutants were detected, among which, benzopyrene, hexachloro-benzene, DDT, and BHC had the coefficients of variation > 1, and their local enrichment degree was high, with greater fluctuation in concentration. The soil organic pollution in the suburbs presented a pattern of "one more and three less" , I. E. , more sampling points with detected organic pollutants, less kinds of detected organic pollutants, less concentration of the organic pollutants , and no sampling points exceeded the standards. Due to the effects of the lithology of soil vadose zone, the suburb soils showed an obvious vertical stratification pattern of organic pollution. It was considered that the regional distribution of suburb soil organic pollution had higher consistency with land use function, and thus, to analyze the main factors affecting the concentrations and distribution characteristics of organic pollutants in suburb soils would be of significance in preventing and

  5. STUDY OF BIOMARKERS SELECTION OF THE SCALLOP CHLAMYS FARRERI EXPOSED TO B[A]P%栉孔扇贝在B[a]P胁迫下生物标志物筛选的研究

    Institute of Scientific and Technical Information of China (English)

    潘鲁青; 刘娜; 王静

    2012-01-01

    研究采用染毒→清除→二次染毒实验,研究了B[a]P对栉孔扇贝组织解毒代谢酶活力和DNA损伤的影响,筛选了栉孔扇贝在B[a]P胁迫下的生物标志物.结果表明:B[a]P对栉孔扇贝鳃丝、消化盲囊芳烃羟化酶(AHH)、谷胱甘肽硫转移酶(GST)活力和还原型谷胱甘肽含量(GSH)及DNA损伤影响显著(P<0.05),而对照组无明显变化.在一次染毒(0-15d)期间,除0.05 μg/L B[a]P处理组鳃丝AHH活力与对照组无明显差异外,其他处理组组织AHH活力均被显著诱导,于15d时达到最大值,GST活力和GSH含量则呈逐渐下降趋势,5d时达到最小值,之后趋于稳定;而组织DNA链断裂(F值)基本呈下降趋势,DNA-蛋白质交联(DPC值)呈逐渐升高,至15d时分别达到最小值和最大值.在清除(15-45d)阶段,各处理组组织AHH活力逐渐下降,GST活力和GSH含量则逐渐升高,在25-40d时均恢复至对照组水平;各处理组组织F值和低浓度处理组(0.05、0.5 μg/L)DPC值分别呈逐渐升高和下降趋势,于35-40d时恢复至对照组水平,而高浓度处理组(5、10 μg/L)DPC值仍显著高于对照组水平.在二次染毒(45-60d)期间,除鳃丝AHH活力在50d时达到最大值外,其他指标变化趋势与一次染毒基本一致.由此可见,栉孔扇贝在B[a]P胁迫下组织解毒代谢酶活力和DNA损伤表现出明显的时间剂量效应性和稳定性,依据相关性分析,提出以鳃丝AHH活力和消化盲囊GST活力为防御型生物标志物,鳃丝、消化盲囊DPC值为损伤型生物标志物,并将AHH、GST活力和DPC值整合作为B[a]P毒性评定的组合型生物标志物,全面评价PAHs的污染毒性.%Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants derived from incomplete combustion of carbon. As a pollutant, they are of concern because some compounds have been identified as carcinogenic, mutagenic and teratogenic. Benzopyrene (B[α]P) is a five-ring polycyclic aromatic

  6. Fifty years after Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    be used for transportation of the army corps in Hiroshima. Therefore there is a possibility that various toxic substances, mutagenic or carcinogenic agents such as benzopyrene and other radiomimetic substances could have been released from various facilities which were destroyed at the time of the atomic bombing. The enormous difference in dose rates between the atomic bombings and the radiation sources used for calibration experiments may also have some effect on some dosimetric systems or on some biological systems. Although it may be difficult to quantify some of these uncertainties, it is extremely important to keep all these uncertain factors in mind when analysing the atomic bomb effects of Hiroshima and Nagasaki. In Japan, medical X-ray examination is compulsory in schools, factories and companies. With certain diseases such as tuberculosis and some diseases of the lung and digestive systems extensive X-ray examinations may be conducted and periodically repeated. Survivors with a relatively low dose of high dose rate atomic bomb radiation must also have received some relatively low dose of low dose rate medical X-ray radiation. In other words, they must have received both high dose rate radiation and low dose rate radiation. There is a possibility of non-probabilistic uncertainties involved in estimation of the relative proportion of the two types of radiation and even greater uncertainties would be involved in the estimation of the organ doses. In these uncertainties both randomness and fuzziness may be involved.Under such situation it may be important to consider application of fuzzy theory for the analysis of cause-effect relationships. In exploding an atomic bomb, in addition to ionizing radiation, strong non-ionizing radiations, such as infrared, ultraviolet light, visible light, electromagnetic pulse radiation, as well as heat and shock waves are produced. Therefore, the possibility of the combined effects of all these direct factors and the indirect

  7. STUDY OF BIOMARKERS SELECTION OF THE SCALLOP CHLAMYS FARRERI EXPOSED TO B[A]P%栉孔扇贝在B[a]P胁迫下生物标志物筛选的研究

    Institute of Scientific and Technical Information of China (English)

    潘鲁青; 刘娜; 王静

    2012-01-01

    研究采用染毒→清除→二次染毒实验,研究了B[a]P对栉孔扇贝组织解毒代谢酶活力和DNA损伤的影响,筛选了栉孔扇贝在B[a]P胁迫下的生物标志物.结果表明:B[a]P对栉孔扇贝鳃丝、消化盲囊芳烃羟化酶(AHH)、谷胱甘肽硫转移酶(GST)活力和还原型谷胱甘肽含量(GSH)及DNA损伤影响显著(P<0.05),而对照组无明显变化.在一次染毒(0-15d)期间,除0.05 μg/L B[a]P处理组鳃丝AHH活力与对照组无明显差异外,其他处理组组织AHH活力均被显著诱导,于15d时达到最大值,GST活力和GSH含量则呈逐渐下降趋势,5d时达到最小值,之后趋于稳定;而组织DNA链断裂(F值)基本呈下降趋势,DNA-蛋白质交联(DPC值)呈逐渐升高,至15d时分别达到最小值和最大值.在清除(15-45d)阶段,各处理组组织AHH活力逐渐下降,GST活力和GSH含量则逐渐升高,在25-40d时均恢复至对照组水平;各处理组组织F值和低浓度处理组(0.05、0.5 μg/L)DPC值分别呈逐渐升高和下降趋势,于35-40d时恢复至对照组水平,而高浓度处理组(5、10 μg/L)DPC值仍显著高于对照组水平.在二次染毒(45-60d)期间,除鳃丝AHH活力在50d时达到最大值外,其他指标变化趋势与一次染毒基本一致.由此可见,栉孔扇贝在B[a]P胁迫下组织解毒代谢酶活力和DNA损伤表现出明显的时间剂量效应性和稳定性,依据相关性分析,提出以鳃丝AHH活力和消化盲囊GST活力为防御型生物标志物,鳃丝、消化盲囊DPC值为损伤型生物标志物,并将AHH、GST活力和DPC值整合作为B[a]P毒性评定的组合型生物标志物,全面评价PAHs的污染毒性.%Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants derived from incomplete combustion of carbon. As a pollutant, they are of concern because some compounds have been identified as carcinogenic, mutagenic and teratogenic. Benzopyrene (B[α]P) is a five-ring polycyclic aromatic