重庆市煤矸山周边农用地土壤重金属污染评价和定量溯源解析

以重庆市南川区某煤矸山周边农用地土壤为研究对象,运用内梅罗指数法、地累积指数法和GIS地统计分析土壤重金属污染水平和分布特征,并采用相关性分析、主成分分析（PCA）和绝对因子得分-多元线性回归分析（APCS-MLR）,探析研究区土壤重金属来源及其贡献率.结果表明,煤矸山周边旱地土壤中8项重金属含量均显著高于水田（P<0.05）,Cd、Hg、As、Pb和Cr含量显著高于园地（P<0.05）;园地土壤中Cu、Ni和Zn含量显著高于水田（P<0.05）.内梅罗综合污染指数表现为旱地（2.77）>园地（1.04）>水田（0.59）,重金属污染程度由大到小表现为：Cd>Cu>Ni>Zn>Hg、As、Cr和Pb.污染累积程度由大到小表现为：Cd>Hg>Cu>Ni>Zn>As>Cr>Pb.污染源解析表明,Cd和Hg存在显著正相关关系（r=0.756,P<0.01）,主要受到煤矸山长期堆存等矿业活动影响,贡献率分别为51.6%和52.9%.Cu、Ni和Zn之间存在显著正相关关系（r为0.755~0.955,P<0.01）,主要受到施肥等农业活动影响,贡献率分别为72.3%、63.3%和59.2%.As和Pb主要受到土壤母质等自然因素影响,贡献率分别为60.8%和86.9%.Cr主要受到施肥等农业活动和土壤母质等自然因素共同影响,贡献率分别为38.9%和40.9%.应重点加强对Cd的来源管控和污染防治.     

典型酚类污染物内分泌干扰效应研究——对斑马鱼发育及核受体介导基因调控的分子影响

以斑马鱼为研究对象,观察2,4,6-三氯酚（2,4,6-trichlorophenol）、4-氯-3-甲酚（4-chloro-3-methylphenol）和4-硝基苯酚（4-nitrophenol）3种酚类污染物对斑马鱼胚胎发育早期阶段形态学指标的影响,借助q-RT-PCR方法对斑马鱼胚胎分别暴露于0.1,0.5和2.5mg/L至120hpf幼鱼8个重要受体（雄激素受体（AR）、甲状腺激素受体（TR）、芳香烃受体（AhR）、雌激素受体（ER）、糖皮质激素受体（GR）、孕烷X受体（PXR）、盐皮质激素受体（MR）、过氧化物酶体增殖物激活受体（PPAR））相关基因的转录水平进行了研究;进一步采用分子对接和分子动力学模拟的方法研究污染物与筛选出的影响受体（ER、AhR、PXR、GR以及MR）之间的相互作用过程.结果表明,在5和10mg/L的浓度下3种酚类污染物都显著影响斑马鱼的发育,造成脊柱弯曲、心包水肿等不良影响;基因结果显示2,4,6-三氯酚暴露导致ER的基因下调,雌激素受体α（er1）基因在2.5mg/L浓度下下调2.1倍.4-氯-3-甲酚显著影响ER、AhR以及PXR的相关基因,表现为在0.5和2.5mg/L暴露er1基因显著下调1.8和2.2倍,ahr2和pxr基因在0.1和2.5mg/L的浓度下分别下调1.7和1.8倍和上调3.5和3.2倍.4-硝基苯酚暴露使GR、MR核心受体基因发生调控变化,糖皮质激素受体基因（gr）在低中浓度下分别显著上调2.0和2.1倍,最高浓度下下调1.9倍.盐皮质激素受体基因（mr）在中高浓度下分别下调1.9和2.1倍,在最低浓度下显著上调1.7倍;分子计算结果显示它们与相关受体通过疏水和氢键等相互作用而稳定结合,且均方根偏差（RMSD）在5ns后稳定.这3个典型酚类污染物主要通过斑马鱼ER、AhR、PXR、GR、MR受体介导产生内分泌干扰效应并影响其早期生长发育.     

基于多通道分布式VOCs在线监测质谱系统精准识别企业污染源

建立一套适用于工业园区VOCs无组织排放的监管溯源系统,该系统通过多通道分布式质谱在企业内部和厂界进行多个在线监测点位连续监测,实现对VOCs的无组织排放污染源的初步识别.监测数据结合正交矩阵因子分解(PMF)模型和二元条件概率函数(CBPF)方法精准识别园区内不同范围尺度的污染源.该系统成功应用于台州市化工园区内某医...     

应用受体学说模型研究硝基苯类化合物的致毒机理

应用受体学说推出的定量结构活性相关(QSAR)模型研究了硝基苯类化合物的致毒机理,结果表明,硝基苯类化合物的主要致毒机理是化合物亲电中心与受体分子亲核活性中心发生反应．并引入硝基数目和位置指示变量I,分析表明,苯环上硝基的数目和位置的差别引起化合物的最低未占轨道能ELUMO的变化,即化合物亲电结合能的变化,从而影响了化合物的生物活性．     

基于受体作用理论的类雌激素效应测试方法

以17β雌二醇为标准参考物质,对基于受体作用理论的环境激素分析方法实验条件进行了重构和优化,建立了环境类雌激素分析方法。结果表明:用营养缺陷型培养基30℃恒温振荡66 h培养时间进行重组基因酵母的复苏与增殖,20℃～35℃水浴样品与酵母混合液培养3～6 h暴露,优先选用机溶剂处理法释放β-半乳糖苷酶,35℃恒温水浴进行酶活测试反应,采用反应终止后2.5 h 420 nm波长进行分析测试,同时实际样品的分析,加测不少于一个的稀释水样效应值,可使方法更加科学高效、准确度高,应用于各类实际样品分析。     

Screening of monoclonal antibodies recognizing oncofetal antigens for isolation of trophoblasts from maternal blood for prenatal diagnosis

Many monoclonal antibodies have been produced against tumour-associated cell surface antigens for cancer therapy. They have therefore been selected for minimal reactivity with normal tissues and in particular for lack of binding to blood cells or serum components. Many of the antigens recognized are of fetal origin. These monoclonal antibodies may therefore be ideal candidates to recognize and sort fetal trophoblasts from maternal blood for prenatal diagnosis of genetic abnormalities. A panel of 19 anti-tumour antibodies were therefore screened for reactivity with early trimester placenta and two, 340 and 154, were shown to stain trophoblasts. If MAb 340 is linked to magnetic beads, it can efficiently sort trophoblast cell lines from whole blood.     

Phenotypic analysis of fetal blood leucocytes: Potential for prenatal diagnosis of immunodeficiency disorders

Recent technological advances allow the detection and quantitation of subsets of leucocytes using monoclonal antibodies. We have taken advantage of this to study the ontogeny of fetal blood leucocytes, using very small blood samples obtained at fetoscopy. By 14 weeks gestation T cells represent 35 per cent or more of fetal leucocytes and the distribution of the helper/inducer and suppressor/cytotoxic subsets is similar to that of adults. B lymphocytes before 161/2 weeks are low (4–20 per cent), but rise to a mean of 28 per cent in 17–26 week fetuses. Granulocytic cells, many of which are phenotypically immature, represent 18–34 per cent of total leucocytes. The methodology employed is very reliable and offers the opportunity for the prenatal diagnosis of some immunodeficiency disorders, since using the same reagents we have diagnosed children with severe combined immunodeficiency shortly after birth.     

Prenatal analysis of insulin receptor autophosphorylation in a family with leprechaunism

We describe a method for the isolation and functional characterization of insulin receptors from chorionic villi and cultured amniotic fluid cells. The functionality of these receptors is assayed by measuring the insulin-induced stimulation of autophosphorylation of the receptor β-chain. The method is expected to allow the prenatal diagnosis of those forms of lep-rechaunism and related diseases which are the result of a decreased stimulation by insulin of receptor autophosphorylation. A pregnancy at risk for leprechaunism was examined and an unaffected child was correctly predicted by study of the functionality of the insulin receptor on cultured amniocytes and by echoscopic examination.     

Blood transferrin receptor expression in chromosomally abnormal fetuses

In a cross-sectional study of 13 chromosomally abnormal fetuses, umbilical venous blood was obtained by cordocentesis at 17–32 weeks' gestation. Fetal blood transferrin receptor (CD71) expression (mean=79·8 per cent, range=60–98 per cent) and nucleated red cell count (mean=10·4 × 10⁹ per 1, range=1·0–25·0 × 10⁹ per 1) were significantly higher than the appropriate normal mean for gestation (z=3·92, P<0·0001 and z=3·69, P<0·001, respectively). These haematological changes in chromosomally abnormal fetuses would facilitate their prenatal diagnosis by analysis of fetal nucleated red blood cells isolated from the maternal circulation on the basis of CD71 expression.     

Prenatal overgrowth and mosaic trisomy 15q25-qter including the IGF1 receptor gene

Overgrowth is rarely associated with chromosomal imbalances. Here, we report on a male foetus presenting with overgrowth and additional material on the short arm of one of the chromosome 15 in 12% of lymphocytes and 50% of amniotic cells. Parents' karyotypes were normal, indicating a de novo origin for this unbalanced rearrangement. Complementary studies using cytogenetic and FISH studies showed that this additional material resulted in a 15q25-qter trisomy and confirmed the presence of three copies of the insulin-like growth factor 1 receptor (IGF1R) gene, included in the trisomic region. Autopsy performed after termination of pregnancy revealed isolated overgrowth and absence of visceral malformations. The possible mechanisms and origins for the formation of this mosaic pure trisomy are complex. The present observation emphasises the hypothesis that the overgrowth phenotype, frequently reported in patients with trisomy including the 15q26 region, might be causally related to a dosage effect of the IGF1R gene, as well as the importance of chromosome analysis in patients with overgrowth. It also confirms that the overgrowth is of prenatal onset in those observations. Copyright © 2004 John Wiley & Sons, Ltd.