Ecotoxicological Risk Assessment of Polychlorinated Biphenyls (PCBs) in Bank Sediments from along the Yamuna River in Delhi,India

The River Yamuna originates from the Yamunotri glacier of the Himalayas and travels 22 km in the Delhi region. The river is used for various purposes in Delhi including drinking water supply. Twenty-eight polychlorinated biphenyls (PCBs) congeners were measured in bank sediments along the river, and their ecotoxicological risk was evaluated. Concentrations of ∑28PCBs varied from 0.20–21.16 ng g^?1 (dry wt.) with mean and median values of 6.63 ng g^?1 and 5.84 ng g^?1 (±0.69 ng g^?1), respectively. The concentration of 12 dl-PCBs concentrations varied from 0.04–2.86 ng g^?1 with a mean of 1.04 ± 0.11 ng g^?1, and their toxic equivalency ranged between <0.01–28.67 pg WHO-TEQ g^?1 with a mean of 10.77 ± 1.06 pg WHO-TEQ g^?1. CB-37, CB-44, CB-114, and CB-118 congeners were dominant among all PCBs congeners. The tri-PCBs (49%) were the main contributors to the PCB homolog followed by tetra-PCBs (35%), and penta-PCB (14%). Because there are no environmental guidelines in India for PCBs in river and marine sediments, concentrations of PCBs and their toxic equivalents were compared in a screening-level assessment with established freshwater sediment quality guidelines and found lower than those guideline values, which suggests no adverse ecotoxicological effect.     

Molecular assessment of the potential for in situ bioremediation of PCBs from aquatic sediments

Polychlorinated biphenyls (PCBs) are a family of xenobiotic compounds that are ubiquitous and oftentimes persistent environmental pollutants. As such, PCBs are a common target of sediment remediation efforts. Microbial degradation of sediment pollutants such as PCBs offers an environmentally sound and economically favorable alternative to conventional means of remediation such as dredging. This project describes the development of a PCR-based assay to determine the potential for PCB bioremediation by the resident microbial consortium in contaminated sediments. Using PCR and RT-PCR of DNA and RNA, respectively, extracted from aquatic sediments collected from the western basin of Lake Erie and one of its tributaries, we were able to amplify the bphA1 gene that encodes the large subunit of biphenyl dioxygenase. Since other studies have determined that the BphA1 gene product dictates PCB congener specificity, this assay may prove to be a useful screen for endemic catabolic activities for PCB mixtures in aquatic sediments.     

Polychlorinated biphenyls in vegetable soils from Changchun,Northeast China: Concentrations,distribution, sources and human health risks

To investigate the occurrences of polychlorinated biphenyls (PCBs) in suburban vegetable soils of Changchun area, Northeast China, 106 urban vegetable soil samples were collected from Changchun City, Nongan County, Dehui City, Yushu City, Jiutai City, Shuangyang District. We analyzed the concentrations, compositions and sources of 7 PCBs in top soils of Changchun area, and evaluated the non-carcinogenic and carcinogenic risk of PCBs pollution to exposed population. The total concentrations of 7 PCBs ranged from 1.31 to 148 ng/g dry weight (dw) with a mean value of 42.0 ng/g and dominated by Hepta-CBs and Penta-CBs. Principal component analysis (PCA) revealed that PCB pollution in soils of Changchun area mainly related to transportation, vehicle emissions, paints and other industries. Human health risk assessment showed that the cumulative non-carcinogenic and the cumulative carcinogenic risk in children and adults in the industrial land and residential land were acceptable, considering only 7 PCBs homologues were analyzed in this study, the actual risk could be higher.     

利用雨养泥炭沼泽及湖泊沉积物重建多氯联苯污染时空变化趋势

为了重建不同历史时期多氯联苯(PCBs)的沉降速率以研究其污染的时空变化趋势,本研究分析了PCBs在泥炭芯和湖泊沉积柱芯中浓度和沉降速率的变化规律,并评估了泥炭芯和湖泊沉积柱芯用于PCBs沉降变化研究的适用性.对采集柱芯进行定年分析发现,泥炭沼泽可以很好地记录PCBs历史沉降变化,并且泥炭中的PCBs没有出现降解情况,...     

Isolation and Characterization of Acidic Peptides in Soy Sauce

A soy sauce sample was fractionated by gel filtration on a Sephadex G–15 column, then the fractions were subfractionated on the basis of acidity by ion exchange chromatography on a QAE-Sephadex A–25 column. The acidic subfractions with various acidities were further fractionated, using a preparative amino acid analyzer and by paper chromatography to separate the acidic peptide components.

Four dipeptides and sugar derivatives of ten dipeptides and two tripeptides were isolated and characterized as the major acidic peptides in soy sauce. However, it was difficult to anticipate any direct contribution of these peptides to the flavor construction in soy sauce on the basis of their contents and taste intensities.     

Newer Classification and Regression Tree Techniques: Bagging and Random Forests for Ecological Prediction

The task of modeling the distribution of a large number of tree species under future climate scenarios presents unique challenges. First, the model must be robust enough to handle climate data outside the current range without producing unacceptable instability in the output. In addition, the technique should have automatic search mechanisms built in to select the most appropriate values for input model parameters for each species so that minimal effort is required when these parameters are fine-tuned for individual tree species. We evaluated four statistical models—Regression Tree Analysis (RTA), Bagging Trees (BT), Random Forests (RF), and Multivariate Adaptive Regression Splines (MARS)—for predictive vegetation mapping under current and future climate scenarios according to the Canadian Climate Centre global circulation model. To test, we applied these techniques to four tree species common in the eastern United States: loblolly pine (Pinus taeda), sugar maple (Acer saccharum), American beech (Fagus grandifolia), and white oak (Quercus alba). When the four techniques were assessed with Kappa and fuzzy Kappa statistics, RF and BT were superior in reproducing current importance value (a measure of basal area in addition to abundance) distributions for the four tree species, as derived from approximately 100,000 USDA Forest Service’s Forest Inventory and Analysis plots. Future estimates of suitable habitat after climate change were visually more reasonable with BT and RF, with slightly better performance by RF as assessed by Kappa statistics, correlation estimates, and spatial distribution of importance values. Although RTA did not perform as well as BT and RF, it provided interpretive models for species whose distributions were captured well by our current set of predictors. MARS was adequate for predicting current distributions but unacceptable for future climate. We consider RTA, BT, and RF modeling approaches, especially when used together to take advantage of their individual strengths, to be robust for predictive mapping and recommend their inclusion in the ecological toolbox.     

秦岭山地天然次生林群落MRT数量分类、CCA排序及多样性垂直格局

采用多元回归树(MRT)对秦岭山地天然次生林群落进行数量分类,采用典范对应分析(CCA)进行排序,分析了秦岭山地天然次生林群落物种多样性沿海拔梯度的变化规律。结果表明:(1) 275个样方共有种子植物195种,隶属61科128属。乔、灌、草3个层次物种多样性变化沿海拔梯度的变化趋势基本一致,呈单峰模型;(2)经交叉验证认为秦岭山地天然次生林群落可分为2类,Ⅰ冬瓜杨(Populus purdomii)+陇东海棠(Malus kansuensis)+蛇莓(Duchesnea indica)群落,Ⅱ锐齿槲栎(Quercus aliena var. acuteserrata)+黄栌(Cotinus coggygria)+茜草(Rubia cordifolia)群落;(3) CCA排序结果揭示了群落生境的分布范围,反映出生态轴的排序意义,较好地反映秦岭山地天然次生林群落与环境因子的关系,其结果表明,海拔、坡向、凋落层厚度和干扰情况4个变量对该地区次生林群落的分布有较大的影响。     

Issues Related to Chemical Analysis,Data Reporting,and Use: Implications for Human Health Risk Assessment of PCBs and PBDEs in Fish Tissue

Recent reports in the scientific literature and the media, related to elevated levels of polychlorinated biphenyls (PCBs) and polybrominated diethyl ethers (PBDEs) in farmed and wild salmon have had significant impacts on public opinion and consumer behavior, influencing the sales of farmed salmon in North America and Europe. The assessment of contaminants in fatty fish, an important source of omega-3 fatty acids, is therefore an exercise in balancing risks and benefits. Human health risk assessors and risk managers will benefit from an understanding of the level of uncertainty that is integrated into all aspects of evaluating risk in this context. Significant variability exists in the way in which analyses are conducted, how data are reported, and how they are used in risk assessments. We conducted an analytical review of PCB and PBDE data in farmed and wild salmon, and identified critical issues having implications on human health risk assessment from fish consumption. These issues include: analytical methodologies used, quantification issues, reporting of QA/QC information, tissue sampling, nature of tissue analyzed, and laboratory competence. This article reviews and outlines these issues, discusses their implications for human health risk assessment, and recommends the consistent application of analytical fish tissue data in human health risk assessment.     

甘蔗节间蔗糖含量与和蔗糖代谢相关的4种酶活性之间的关系剖析

测定和分析2个品种甘蔗节间蔗糖含量与和蔗糖代谢相关的4种酶活性之间关系的结果表明:节间蔗糖含量与酸性转化酶活性成极显著负相关,与蔗糖磷酸合成酶活性呈显著正相关。从通径分析结果可知,4种关键酶中可溶性酸性转化酶和蔗糖磷酸合成酶是对蔗糖含量贡献程度最大的2个酶.     

桂林岩溶石山青冈群落数量分类与排序

植物群落的数量分类和排序可以客观地揭示植物群落与环境之间的关系,从而能为植被恢复与重建、森林经营与管理和生物多样性保护等提供理论依据。基于群落学调查和环境因子测定数据,采用Ward聚类、双向指示种分析(TWINSPAN)和多元回归树(MRT)对桂林岩溶石山青冈群落进行数量分类,选用冗余分析(RDA)进行排序,分析其与环境因子之间的关系。结果表明:(1)3种分类方法所得结果基本一致,可将桂林岩溶石山青冈群落划分为3个群丛类型,分别为青冈-粗糠柴+龙须藤+红背山麻杆-三穗薹草群丛(Ass.Cyclobalanopsis glauca-Mallotus philippensis+Bauhinia championi+Alchornea trewioides-Carex tristachya)、青冈-龙须藤+红背山麻杆+干花豆-宽叶沿阶草+三穗薹草群丛(Ass.Cyclobalanopsis glauca-Bauhinia championi+Alchornea trewioides+Fordia cauliflora-Ophiopogon platyphyllus+Carex tristachya)、青冈-粗糠柴+干花豆-三穗薹草群丛(Ass.Cyclobalanopsis glauca-Mallotus philippensis+Fordia cauliflora-Carex tristachya);(2)冗余分析结果较好地反映出各群丛类型的分布格局及其与环境梯度的相互关系,在10个环境因子中,岩石裸露率、土壤含水量、pH值、全氮、全磷、全钾、速效钾这7个环境因子对群落的分布影响显著。土壤含水量和全钾含量可能是影响该植物群落物种组成与分布的重要生态因子。     

Role of the Brainstem Reticular Formation in the Mechanisms of Cortical Electrogenesis

In rats, we studied peculiarities of the electrocorticogram (ECoG) and its segments characterized by synchronization and desynchronization phenomena; these periods were differentiated using a segmentation procedure. The electrocorticogram was recorded under conditions of the intact brain (IB) and in animals with the isolated forebrain (IFB) using intercollicular transection. When ECoG was recorded from IFB preparations, it differed from ECoG of the IB in decreased amplitudes of the rhythms and their reorganization with shifts of the frequency characteristics toward lower values, as well as in greater amplitudes of ECoG rhythms in the left hemisphere (lateralization of the ECoG activity toward this hemisphere). Significant differences of the indices of functional asymmetry were observed in the two examined experimental situations. Using calculations of multiple linear regression and subsequent visualization of the results using polycyclic multigraphs, we found a clear specificity in the formation of correlation links between the amplitudes of different ECoG rhythms under conditions of the IB and IFB preparation. We discuss the role of the brainstem structures, in particular that of the reticular formation, in the organization of integral ECoG activity and the possible importance of mutual influences between hypothetical generators of the ECoG rhythmus for this organization.Neirofiziologiya/Neurophysiology, Vol. 37, No. 1, pp. 39–51, January–February, 2005.     

Serum C‐reactive protein in the prediction of cardiovascular diseases: Overview of the latest clinical studies and public health practice

Cardiovascular disease is the most common cause of morbidity and mortality globally. Epidemiological studies using high‐sensitivity assays for serum C‐reactive protein have shown a consistent association between cardiovascular disease risk and serum C‐reactive protein concentrations. C‐reactive protein is a biomarker for inflammation, and has been established in clinical practice as an independent risk factor for cardiovascular disease events. There is evidence that serum C‐reactive protein is an excellent biomarker of cardiovascular disease and is also an independent and strong predictor of adverse cardiovascular events. Further characterization of the impact and influence of lifestyle exposures and genetic variation on the C‐reactive protein response to cardiovascular disease events may have implications for the therapeutic approaches to reduce cardiovascular disease events. This review summarizes the studies that have examined the association between serum C‐reactive protein and the risk of cardiovascular disease. We also discuss the impact of independent factors and C‐reactive protein genetic polymorphisms on baseline plasma C‐reactive protein levels.     

苯丙酮尿症(PKU)患者血清的氨基酸定量分析(英文)

目的 PKU患者血清中游离氨基酸组成及定量分析。方法 应用日立835-50型氨基酸自动分析仪进行测定。结果 七例PKU患者血清中Phe患者血清中Phe (1.5480.080) 和Glu (0.4680.098) 的含量分别为正常组Phe (0.1070.014) 和Glu (0.1330.046) 的15倍和3.5倍,差异非常显著 (p<0.001)。Arg (0.0330.046) 为正常组 (0.1130.025) 的1/4 (p<0.001)。但患者血清中Tyr (0.0500.016) 与正常值 (0.0470.008) 相比则无显著性差异 (p>0.05)。结论 用氨基酸分析方法可准确测定PKU血清中各种氨基酸含量,为PKU诊断提供了可靠的数据: 并发现除Phe外,还有Arg的异常降低及Glu的异常升高,其发生机理及临床意义有待进一步研究。     

The past,present and future of thermophilous Cyperus polystachyos Rottb. (Cyperaceae) on the island of Ischia (southern Italy)

Cyperus polystachyos is a hygrophilous, thermophilous and heliophilous plant with a punctiform distribution in southern Italy, where it is almost exclusively found on Ischia, an island in the Bay of Naples characterized by widespread volcanic hydrothermal activity. This species is a native of tropical and subtropical areas and there is evidence for ancient isolation events in the creation of its current distribution pattern. We have studied the historical literature available for this plant since 1800 and collected temporal and spatial presence data of this species in order to develop a habitat suitability map based on a GIS approach and using a multiple linear regression model. Moreover, we have used univariate and multivariate statistical analysis. The results show the importance of the environmental mosaic around fumaroles to preserve the species; urbanization and geothermal energy use of fumaroles in the past and the combination of abandonment of the typical agricultural system and the natural occurrence of reforestation in the present are the main causes of the decline in the number of populations.     

Sensitive biomarker of polycyclic aromatic hydrocarbons (PAHs): urinary 1-hydroxyprene glucuronide in relation to smoking and low ambient levels of exposure

The lysosomal neutral red retention time (NRRT) assay, a biomarker for lysosomal membrane stability, and the total immune activity (TIA) assay, a measure of non-specific immune system activity, were used in laboratory studies to assess the toxic effects of 2,4,6-trinitrotoluene (TNT) on earthworms (Eisenia andrei) in vivo. The results were compared with the concentration of TNT and its metabolites in earthworm tissue, as well as standard sublethal toxicity endpoints including growth (i.e. weight change) and reproduction effects from previously published studies. Filter paper experiments indicated a significant decrease in NRRT at ≥1.8 μg TNT cm^-2, whereas sublethal (weight loss) and lethal effects to earthworms were detected at ≥3.5 and 7.1 μg TNT cm^-2, respectively. Experiments in artificial soil showed that NRRT effects could be detected at lower TNT concentrations (≥55 mg TNT kg^-1 soil dry weight) compared with other sublethal endpoints (effects on growth and reproduction). The TIA biomarker did not significantly respond to TNT. Copper (as CuSO₄, filter paper contact tests) and 2-chloroacetamide (soil tests), which were used as reference toxicants, also decreased the NRRT. The use of the NRRT assay linked with tissue concentrations of TNT metabolites in earthworms was identified as a potentially appropriate biomarker approach for TNT exposure assessment under laboratory conditions and a novel tool for effects-based risk assessment.     

太白山自然保护区典型森林群落数量分类、排序及多样性格局

通过多元回归树（MRT,multivariate regression trees）对太白山自然保护区典型森林群落进行数量分类,采用典范对应分析（CCA,canonical correspondence analysis）进行排序,并对分类得到的森林群落总体多样性进行分析。研究表明：（1）对30个样地进行MRT分类,经交叉验证得出太白山自然保护区典型森林群落可以分为6类。（2）CCA排序揭示了群落的生境分布范围,并反映了太白山森林群落与环境因子的关系,研究表明,海拔、坡度、枯落物厚度和干扰情况4个变量对本研究区群落分布有显著影响。（3）位于中海拔区域森林群落的3种总体多样性指数均较高,而位于高海拔和低海拔区域森林群落的3种总体多样性指数相对较低。     

The Use of Multiple Outcomes Analysis in Neurotoxicity: An Example from the New Zealand Study of Offspring of Mothers Exposed to Methyl Mercury

Neurotoxicity has become an important area in the study of the risk to children of noncarcinogens. Many of the tests used to evaluate neurotoxic effects in neurotoxic studies are psychometric tests to assess cognitive, motor, and perceptual performance in individuals in order to determine the presence of psychological problems, impaired educational achievement, or neurological abnormalities. The underlying assumption of these procedures are that a test performance deficit is indicative of a neurological disability, and that such disability derives from the prenatal exposure to an offending substance. The usual analytic paradigm for discerning environmental impacts is to analyze the scores of a particular subtest in a battery taken separately as the dependent variable with regression analysis, which adjusts for cultural background, educational level, and socioeconomic status. The impact of this analysis is to determine the correlation of each of the psychometric test results to exposure. We show a statistical method to simultaneously analyze the multiple outcomes of many tests using General Estimating Equations (GEE) to determine if a correlation exists between the global measure of all these tests and exposure adjusted for covariates of interest and the correlation among the dependent psychometric variables. We show the application of this method to the results of children whose mothers were exposed to mercury during pregnancy.     

太行山南段连翘群落结构及其影响因子研究

连翘（Forsythia suspensa）不仅是一种常用大宗木本药用植物类型,而且也是重要的绿化植物类型。以太行山南段陵川境内广泛生长的连翘为研究对象,通过样方调查方法,解析连翘群落结构及影响因子,探讨海拔、坡向主要地形因子和土壤因子对群落格局的影响,以期有助于连翘的规模化种植。结果表明：（1）该区连翘群落可分为5类群丛：Ⅰ连翘（Forsythia suspensa）＋三裂绣线菊（Spiraea trilobata）-披针叶苔草（Carex lanceolata）群丛;Ⅱ连翘（Forsythia suspensa）＋白刺花（Sophora davidii）-披针叶苔草（Carex lanceolata）＋铁杆蒿（Tripolium vulgare）群丛;Ⅲ辽东栎（Quercus wutaishanica）-连翘（Forsythia suspensa）＋三裂绣线菊（Spiraea trilobata）-披针叶苔草（Carex lanceolata）+白头翁（Pulsatilla chinensis）群丛;Ⅳ油松（Pinus tabuliformis）-连翘（Forsythia suspensa）-披针叶苔草（Carex lanceolata）群丛;Ⅴ连翘（Forsythia suspensa）＋黄刺玫（Rosa xanthina）-披针叶苔草（Carex lanceolata）群丛。（2）海拔高度（H）、全钾（TK）和坡向（TRP）是影响该区连翘分布状况的3个主要环境因子。3个因子在4个层级水平上构成群落分型的主导因子。第一级主导因子是海拔高度（H=1330 m）;第二级是土壤总钾量（TK=19.07 mg/kg）和海拔（H>1330 m）;第三级是坡向（TRP=0.2775）、海拔（H>1330 m）和总钾量（TK<19.07 mg/kg）;第四级是总钾（TK=18.47 mg/kg）、海拔（H>1330 m）、和坡向（TRP>0.2775）。海拔高度和土壤肥力是影响太行山南段生境内连翘群落结构和规模化种植的要重环境因子。     

孕早中期血清脂联素、抵抗素、铁蛋白水平及与妊娠期糖尿病的相关性分析

目的:研究孕早中期血清抵抗素、脂联素及铁蛋白水平与妊娠期糖尿病的相关性。方法:选取孕早期(11-13周)、孕中期(24-28周)诊断为GDM的孕妇46例作为试验组(GDM组),及同期糖代谢正常的孕妇46例作为对照组(NGT组),检测和比较两组孕早、中期血清脂联素、抵抗素、铁蛋白水平,计算各期胰岛素稳态模型抵抗指数(HOMA-IR),并对孕早中期血清抵抗素、脂联素及铁蛋白(SF)水平与HOMA-IR进行相关性分析。结果:与NGT组比较,GDM组孕早、中期血清脂联素水平均显著降低,且孕早期血清脂联素水平与HOMR-IR呈负相关(r=-0.21,P0.05);孕早、中期血清SF水平均显著升高,且孕早期血清SF水平与IR呈正相关(r=0.238,P0.05);孕早期血清抵抗素水平无明显变化(P0.05),但孕中期血清抵抗素水平显著降低(P0.05)。多元线性回归分析结果显示孕早期血清铁蛋白水平对HOMA-IR的影响更显著,孕早期SF每升高1μg/l,HOMA-IR提高0.179。孕早期SF水平作为预测GDM发病的血清学阈值为≥23.2μg/L。结论:孕早期血清脂联素及SF水平变化均与GDM的发病相关,孕早期血清SF水平可能作为早期诊断和预防GDM的血清学指标。