芳香化合物受体报道基因检测环境二噁英污染

以建立环境二噁英类污染物的筛查方法为目的,考察酵母基因报告系统方法在水、土壤和动物血清样品检测中的准确性和灵敏性。利用该系统,对TCDD标准品和已知毒性当量的环境污染二英标准品进行测试,建立和标准化测定的方法;对各种水样、土壤和动物TCDD暴露模型血清样品进行测定。结果显示报道系统能够较为准确地反映标准样品的毒性当量浓度,可检测到TCDD污染物的下限浓度为0.01 ng/L;可疑河涌水的二噁英类TEQ污染水平在可检测范围内,经过治理后污染程度下降;土壤检测到最高污染水平为(23.06±1.75)ng/kg;TCDD模型小鼠血清含量明显高出正常对照组(p<0.05,p<0.01和p<0.01)。结论:实验证明该报道系统可用于多种实际环境污染样品二噁英类TEQ检测,灵敏度可达ng级。由于方法具有简单、快速的特点,特别适合于环境可疑较高二噁英类污染物的快速筛查,在实际中有一定的应用价值。     

2,3,7,8-Tetrachlorodibenzo-p-dioxin promotes migration ability of primary cultured rat astrocytes via aryl hydrocarbon receptor

Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms are still unclear. During the process of astrocyte reactivation, migration is a critical cellular event. In the present study, we employed wound-healing assay and Transwell® motility assay to explore the effects of TCDD on cell migration in primary cultured rat cortical astrocytes. We found that upon TCDD treatments at relative low concentrations (10^? 10 and/or 10^? 9?mol/L), the ability of primary astrocytes to migrate horizontally and vertically was promoted. In line with this cellular effect, the mRNA expression of two pro-migratory genes, including cell division cycle 42 (CDC42) and matrix metalloproteinase 2 (MMP2) was induced by TCDD treatment. Dioxin exerts its toxic effects mainly through aryl hydrocarbon receptor (AhR) pathway. So the role of AhR pathway in the pro-migratory effects of TCDD was examined using an AhR antagonist, CH223191. We found that application of CH223191 significantly reversed the pro-migratory effects of TCDD. Interestingly, the basal ability of horizontal migration as well as basal levels of CDC42 and MMP2 expression were dramatically reduced suggesting a possible physiological role of AhR in maintaining the endogenous migration ability of the primary astrocytes. These findings support the notion that dioxin promotes astrocyte reactivation at molecular and cellular levels.     

环境毒物——氯化二噁英(TCDD)

氯化二(口恶)英,一般指2,3,7,8-四氯二苯并对二(口恶)英(2,3,7,8-TCDD)。其70余种异构体中,2,3,7,8-TCDD 的毒性最强。TCDD 最初是在除草剂2,4,5-T 中发现,最高量可达2,117±9μg/g(ppm),含量低的也达到 ppb 的数量级。其后在五氯酚钠和2,4-D 中,也发现有微量存在。业已确认,TCDD 是各种商品氯酚     

火星水文地质

空间科学的最新进展,使人们现在已有可能构筑一些关于火星这颗行星的地下水的存在、体积和水循环的模式。 水蒸气的去气模式表明,火星表面理应为厚达10～100m(1.4×10~(15)～1.4×10~(16)m~3)的水所覆盖。地貌证据暗示,火星的大部分表面应当有至少500m深的水(7×10~(16)m~3),但它今天除了在其两极存在冰川冰(2.3×10~(15)—9×10~(15)m~3)外,没有地表水。火星的引力虽然只是地球的40％,但照理应当能使水不逸离该行星。对表面和大气水的体积测量结果表明,火星的大部分水(1.2×10~(16)—6×10~(16)m~3)是作为地下水隐藏起来了。 水循环模式表明,火星有一个活跃、但又近于静态的水循环,这种水循环受沙漠低地中的出水量和两极覆盖的冰川水的补给量所控制。在这个系统中,地下水流起主要作用。     

Enhanced hepatotoxicity induced by repeated exposure to polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin in combination in male rats

2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) and polychlorinated biphenyls(PCBs) are among persistent polyhalogenated aromatic hydrocarbons that exist as complex mixtures in the environment worldwide.The present study was attempted to investigate the hepatotoxicity following repeated exposure to TCDD and PCBs in combination in male rats,and to reveal the involvement of potential mechanisms.Male Sprague-Dawley rats were exposed to TCDD(10 μg/kg) and Aroclor 1254(10 mg/kg,a representative mixture of PCBs) alone ...     

铁矿酸性排水的人工湿地处理

在排放酸性重金属废水的铁矿排土场建设人工湿地处理系统,面积130m~2,废水流量0.5m~3/h,经过两个月的运行测试结果表明:人工湿地系统能有效地处理酸水.酸水pH值由2.6升高到6.1;铜离子由25.79×10~(-6)减少到0.099×10~(-6),去除率为99.7%;铁离子由36.50×10~(-6)降到0.031×10~(-6),去除率为99.8%;锰离子从393.6×10~(-6)降低到107.20×10~(-6),去除率为70.9%.     

2,3,7,8,-四氯苯噁英对NIH小鼠早期妊娠和生殖激素的影响

用不同剂量的2,3,7,8 四氯苯二英(2,3,7,8 tetrachlorodibenzopdioxin,TCDD)对小鼠胚胎附植数量和生长发育情况进行剂量反应评估,分析TCDD对假孕小鼠子宫蜕膜生长状况的影响以及比较胚胎种植前后染毒效果.所有样本采集血液,测定母体血清雌二醇和孕酮的浓度变化.结果表明,50和100ng·(kg·d)-1TCDD处理的孕鼠,胚胎附植数量明显减少(P<0 05),着床后胚胎出现发育迟缓,质量减轻(P<0 05);同等剂量TCDD处理的假孕小鼠,子宫蜕膜生长受到了极显著的抑制(P<0 01);种植前后染毒效果比较发现种植前期染毒的小鼠胚胎对TCDD更为敏感.母体血清雌二醇浓度随剂量和染毒时段有不同程度的升高,而孕酮浓度则极显著下降(P<0 01).由此表明低剂量TCDD可能通过对生殖激素的干扰,强烈影响NIH小鼠妊娠早期生殖生理状态和着床后胚胎的发育.实验同时证明小鼠也可作为早期妊娠毒物研究的供试动物,用以筛选动物和人类早期妊娠的有害化合物.     

甲基丙烯基醛和甲基乙烯基酮水相臭氧化反应

利用实验室模拟的方法研究了甲基丙烯基醛(MAC)和甲基乙烯基酮(MVK)在大气水相中的臭氧化反应,测定了250℃±0.1℃温度和1.0×10⁵Pa空气压力条件下生成过氧化物和二次羰基物的种类和产率.结果表明,MAC水相臭氧化生成2种羰基物(甲醛和丙酮醛)和2种过氧化物,即过氧化氢(H₂O₂)和羟甲基过氧化氢(HOCH₂OOH ,HMHP) ,它们的产率(%)分别为49.9±2.9、26.6±3.9、4.6±0.4和10.0±0.8;同MAC类似,MVK水相臭氧化也生成甲醛、丙酮醛、H₂O₂和HMHP ,它们的产率(%)分别为40.8±2.2、40.7±35、6.8±0.5和10.4±0.8.对MAC和MVK水相臭氧化反应机理进行了推测,解释了各产物的生成.     

沉积物-水系统中氮磷变化与上覆水对藻类生长的影响

研究了灭菌、抑制剂添加和磷添加对沉积物-水模拟系统中氮磷转化的影响,并利用试验后的上覆水培养四尾栅藻.结果表明,灭菌增大了系统平衡时上覆水的总磷(TP)浓度,对系统中氮的影响不大; 添加抑制剂组与对照组沉积物-水模拟系统的TP、溶解性总磷(DTP)和总氮(TN)的浓度接近,但抑制剂组的NO^-₃-N含量为19.2 mg·L^-1,明显高于对照组;沉积物对添加的磷有强烈的吸附作用,导致系统平衡时上覆水TP的浓度降低.灭菌组上覆水的藻类生物量高于对照组,主要是因为灭菌导致上覆水TP浓度高于对照组;抑制剂组的最高藻类生物量(224.5×10⁴个·L^-1)远远超过对照组(26×10⁴个·L^-1),且为其它2组试验(灭菌组22.5×10⁴个·L^-1和磷添加组38.5×10⁴个·L^-1)的5～10倍,抑制剂的添加抑制了沉积物-水模拟系统中微生物对某些元素的利用,而这些元素对藻类生长起重要作用;磷添加对试验初藻类生长无明显影响,随着试验进行,磷添加组的藻类适应生长环境,迅速增长,生物量远远超过对照组.灭菌和添加抑制剂组生物可利用磷的增加是由于藻类生物量的增加,而导致了不稳定态的有机磷的增加.     

Hepatoprotective and antioxidant effects of dietary Glycyrrhiza polysaccharide against TCDD-induced hepatic injury and RT-PCR quantification of AHR2, ARNT2, CYP1A mRNA in Jian Carp (Cyprinus carpio var. Jian)

To evaluate the protective effects of Glycyrrhiza polysaccharide (GPS) against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced hepatotoxicity in Jian carp, the fish were fed diets containing GPS at doses of 0.1, 0.5 and 1.0 g/kg for 60 days before an intraperitoneal injection of 0.6 μg/kg TCDD at a volume of 0.05 mL/10 g body weight. At 72 hr post-injection, blood and liver samples were taken for biochemical analysis and the fish liver samples were used for the preparation of pathological slices. The results showed that increases in alanine aminotransferase (GPT), aspartate aminotransferase (GOT), lactate dehydrogenase (LDH), and alkaline phosphatase (AKP) in serum induced by TCDD were significantly inhibited by pre-treatment with 1.0 g/kg GPS. Following the 1.0 g/kg GPS pre-treatment, total protein (TP), albumin (Alb), catalase (CAT), glutathione peroxidase (GPx), total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activities in liver tissue increased significantly, malondialdehyde (MDA) formation (P < 0.05 or P < 0.01) was significantly inhibited, and the expression of cytochrome P4501A (CYP1A), aryl hydrocarbon receptor 2 (AHR2) and aryl hydrocarbon receptor nuclear translocator 2 (ARNT2) mRNA (P < 0.05) was significantly enhanced. Histological observations on fish liver were obtained by preparing paraffin tissue sections via HE staining, and the results showed that histological changes were obviously reduced by 0.5 and 1.0 g/kg GPS. GPS significantly reduced liver tissue damage caused by TCDD. Overall, these results proved the hepatoprotective effect of GPS in protecting against fish liver injury induced by TCDD, and supported the use of GPS (1.0 g/kg) as a hepatoprotective and antioxidant agent in fish.     

TCDD对乳腺癌细胞端粒酶活性的影响

探讨了2,3,7,8-四氯二苯并-ρ-二噁英(TCDD)在体外对雌激素依赖性乳腺癌细胞MCF-7端粒酶活性的影响.用0.5μmol·L-1的2,3,7,8-四氯二苯并-ρ二噁英(TCDD)作用于MCF-7细胞,裂解后提取MCF.7细胞端粒酶.采用BCA方法定量蛋白、重复序列扩增-银染法检测端粒酶活性.结果表明.TCDD作用MCF-7细胞后,细胞端粒酶活性增强,且随作用时间端粒酶活性减弱,但明显高于对照组(P<0.05).结果表明:TCDD有显著增强MCF-7细胞端粒酶活性的作用.     

雾与人体健康

一、雾的成分及雾天气条件下大气污染情况 1.雾的成分雾是悬浮于近地面层大量的水滴或冰晶,水平能见度小于1公里的现象。纯净的雾是由凝结核和水组成,凝结核是形成雾的必要条件对雾的形成起着重要作用,形成雾的凝结核主要是爱根核(R:2×10~(-7)～2×10~(-5)cm),大核(R:2×10~(-5)～10~(-4)cm)凝结核有可溶性盐和不溶性物质如烟、土壤粒子、尘埃等(主要凝结核如表1)。     

苯酚及苯二酚类催化氧化的色谱电化学法测定及研究

研究了1:12磷钼杂多酸(PMo_(12))修饰电极对苯酚及苯二酚类(对苯二酚、间苯二酚和邻苯二酚)的催化氧化作用,以及苯酚和苯二酚类在涂敷十二烷基磺酸钠(SDS)的C_(18)键合固定相上的分离方法,采用修饰电极色谱电化学法对其进行分离检测。对苯二酚、邻苯二酚、间苯二酚及苯酚的线性范围依次为4.0×10~(-11)mol/l-2.0×10~(-8)mol/l、4.0×10~(-11)mol/l-2.0×10~(-8)mol/l、8.0×10~(-11)mol/l-2.0×10~(-8)mol/l、8.0×10~(-11)mol/l-2.0×10~(-8)mol/l;检测限依次为2.10×10~(-11)mol/l、2.0×10~(-11)mol/l、4.0×10~(-11)mol/l和4.0×10~(-11)mol/l。平行测定8次,相对标准偏差依次为1.7％、3.3％、2.9％和4.4％。方法可用于化工厂废水中苯酚及苯二酚类的测定。     

黑柱石和水之间氢同位素平衡分馏的实验研究

在750-250℃温度范围内,对黑柱石-水之间的氢同位素平衡分馏进行了实验研究。研究中改进了氢同位素交换实验方法,从而保证了精度。研究结果表明,750-550℃温度范围内,黑柱石一水的分馏系数10~3lnα°_(黑柱石-水)=-30.51 10~6/T~2-59.86,550-350℃温度范围内,10~3lnα°_(黑柱石-水)与温度1/T~2间无依赖关系,其值为-105.0±0.7,.250℃时,交换率太低。文中讨论了黑柱石-水之间氢同位素分馏系数与温度、矿物晶体结构、矿物化学组成的关系及其地质意义。     

酚水及煤气化废水的湿式氧化处理

在二升高压釜中研究了酚水(3540mg酚/L、9278mgCOD/L)和煤气化废水(7866mg酚/L、22928mgCOD/L)的湿式氧化处理,反应温度控制在180—250℃,氧分压为9.8×10~5—34.3×10~5Pa。煤气化废水在温度为190—250℃、氧分压为9.8×10~5Pa,反应90min酚去除60—90％及COD降低35—55％。 酚水和煤气化废水的表观动力学研究表现出快速及慢速反应段,反应速率与COD值呈一次方关系,当温度一定时,反应速率与氧分压为0.25级关系,影响程度明显低于温度。     

溴虫腈在甘蓝及土壤中的残留检测及降解动态

建立了用高效液相色谱法检测甘蓝和土壤中溴虫腈残留的分析方法.土壤和甘蓝样品经丙酮/水混合液(体积比为8∶2)提取,用装有无水硫酸钠和中性氧化铝的层析柱净化,用C18柱作为分析柱,甲醇与水混合液(体积比为80∶20)作为流动相,在260nm的检测波长下,用高效液相色谱法定量测定甘蓝和土壤中残留的溴虫腈.在溴虫腈添加质量比为0·1~1·0mg·kg-1范围内,甘蓝和土壤样品的平均回收率为90·6%~93·3%,变异系数为1·9%~11·6%,在上述条件下,甘蓝和土壤中的最低检出限为0·0162mg·kg-1.应用上述方法,测定了10%溴虫腈纳米功能化制剂和10%溴虫腈悬浮剂在甘蓝和土壤中的降解动态.结果表明,10%溴虫腈纳米功能化制剂和10%悬浮剂在甘蓝中的降解动态方程分别为C=4·0431e-0·3103t(R2=0·9528)和C=6·9611e-0·2686t(R2=0·9272),半衰期分别为t0·5=2·2d和2·6d;在土壤中的降解动态方程分别为C=0·2538e-0·1612t(R2=0·9281)和C=0·537e-0·1754t(R2=0·9845),半衰期分别为t0·5=4·3d和3·9d.按推荐剂量的加倍量施药,在甘蓝中的最终残留低于美国国家环保署规定之蔬菜最大允许残留量(1mg·kg-1).10%溴虫腈纳米功能化制剂在甘蓝和土壤中的降解都比10%溴虫腈悬浮剂快,且作物的最终残留量也比较少,所以,溴虫腈纳米功能化制剂能较好地减少其在作物和土壤中的残留.     

Hepatoprotective and antioxidant effects of dietary Glycyrrhiza polysaccharide against TCDD-induced hepatic injury and RT-PCR quantification of AHR2,ARNT2,CYPIA mRNA in Jian Carp(Cyprinus carpio var.Jian)

To evaluate the protective effects of Glycyrrhiza polysaccharide(GPS) against 2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD)-induced hepatotoxicity in Jian carp,the fish were fed diets containing GPS at doses of 0.1,0.5 and 1.0 g/kg for 60 days before an intraperitoneal injection of 0.6 μg/kg TCDD at a volume of 0.05 mL/10 g body weight.At 72 hr post-injection,blood and liver samples were taken for biochemical analysis and the fish liver samples were used for the preparation of pathological slices.The results showed that increases in alanine aminotransferase(GPT),aspartate aminotransferase(GOT),lactate dehydrogenase(LDH),and alkaline phosphatase(AKP) in serum induced by TCDD were significantly inhibited by pre-treatment with 1.0 g/kg GPS.Following the 1.0 g/kg GPS pre-treatment,total protein(TP),albumin(Alb),catalase(CAT),glutathione peroxidase(GPx),total antioxidant capacity(T-AOC) and superoxide dismutase(SOD) activities in liver tissue increased significantly,malondialdehyde(MDA) formation(P 0.05 or P 0.01) was significantly inhibited,and the expression of cytochrome P4501A(CYP1A),aryl hydrocarbon receptor 2(AHR2) and aryl hydrocarbon receptor nuclear translocator 2(ARNT2) mRNA(P 0.05) was significantly enhanced.Histological observations on fish liver were obtained by preparing paraffin tissue sections via HE staining,and the results showed that histological changes were obviously reduced by 0.5 and 1.0 g/kg GPS.GPS significantly reduced liver tissue damage caused by TCDD.Overall,these results proved the hepatoprotective effect of GPS in protecting against fish liver injury induced by TCDD,and supported the use of GPS(1.0 g/kg) as a hepatoprotective and antioxidant agent in fish.     

汞的胶束增溶分光光度法——以镉试剂或镉试剂2B作显色剂

Popa等曾报告Hg(Ⅱ)与镉试剂(Cadion)和镉试剂2B(Cadion 2B)在中性或微酸性介质中形成1:2(Hg:R)的络合物,用苯萃取测定汞。我们利用非离子表面活性剂的增溶作用,研究了这两种试剂在水相中直接测定汞的胶束增溶分光光度法。结果表明其灵敏度比苯萃取法提高3倍。Popa等报告镉试剂测汞的摩尔吸光系数为4.01×10~4,镉试剂2B为3.01×10~4;我们测得镉试剂和镉试剂2B在Triton X-100存在下,对汞的摩尔吸光系数分别为1.20×10~5和     

气相色谱-离子选择电极检测器测定有机氯

用氯离子选择电极作为气相色谱检测器,测定了γ-BHC、三氯甲烷和四氯化碳,其检测下限分别为2.6×10~(-?),1.8×10~(-10)和1.0×10~(-10)mol.以γ-BHC为测定物的相对标准偏差为3.4％,线性范围为2.6×10~(-10)-9.8×10~(-7)mol.     

苯及其衍生物在Pluronic嵌段共聚物胶束水溶液中的增溶

用紫外光谱方法考察 35℃时苯、甲苯、二甲苯和氯苯在Pluronic嵌段共聚物F12 7和P12 3胶束中的增溶 .实验发现 ,当Pluronic嵌段共聚物胶束内核成分固定时 ,增溶量随内核体积 (对苯与氯苯系统 ,还包括栅栏层 )增大而线性增加 ,苯、甲苯、二甲苯和氯苯在每个胶束的最大增溶分子数分别为 4.4× 10 3、2 .3× 10 3、1.4× 10 3 和 7.1× 10 3 个 (F12 7)以及 11× 10 3、6 .8×10 3、4.2× 10 3 和 18× 10 3 个 (P12 3) ,这表明F12 7和P12 3是优良的芳香烃化合物增溶载体 .当苯环上增加甲基时 ,头一个甲基(甲苯 )对增溶量的影响比第二个甲基 (二甲苯 )的影响剧烈