污染黑土中重金属的形态分布与生物活性研究

通过对污染和清洁黑土的耕层、非耕层分层采样分析,比较了Cd,Pb,Cu和Zn等在同一土壤耕层和非耕层以及不同采样点土壤中的形态分布和生物活性.结果表明,无污染黑土中这些重金属的形态分布一般为:残渣态>有机结合态>铁锰结合态>碳酸盐结合态>可交换态,外源污染则使可交换态重金属的含量增加.以生物有效性系数和迁移系数进行重金属生物活性评价,其在黑土中生物活性大小的顺序为:Cd>Cu>Zn>Pb.污染愈严重的土壤,重金属的生物活性和自身的淋溶能力相对较强,在非耕层中也表现出较高的生物活性.综合重金属在土壤中的含量和生物活性,发现2个污染点的黑土中Cd和Pb对当地农业生产和地下水安全已构成潜在的威胁.

植烟土壤有效态微量元素的空间变异及分布特征

以辽宁昌图烟区为例,采用GIS和地统计学相结合的方法,研究了县级区域植烟土壤有效态微量元素的空间变异及分布特征。结果表明:土壤有效态Fe、Mn、Cu、Zn、B、Mo含量的空间变异函数分别为高斯、高斯、球状、指数、指数、指数模型。其中,有效态Cu、Zn、B具有中等的空间相关性,其变异受母质、地形、土壤类型等结构因素和施肥、管理水平等随机因素的共同影响;有效态Fe、Mn、Mo的空间相关性微弱,其变异受随机因素影响较大。点克里格(Kriging)法插值图显示,Fe、Mn、Cu、Zn、B、Mo有效含量均总体呈现南高北低的分布趋势,其中Cu、Zn、B的分布格局相对更加复杂,在北部烟区表现为从西南向东北逐渐增加,在南部烟区表现为自中偏北部向四周逐渐降低。

中国东北北部黑土重金属污染趋势分析

对中国东北北部 2 2个县市黑土可能发生重金属污染的污染源进行了系统调查 ;对土壤样品中Cd、Pb、Cu、Zn进行检测分析 ,4种重金属的检出范围依次为 0 0 1 3— 2 31mg kg ,1 0 5 2— 5 7 48mg kg ,42 1 3— 2 2 7 1 0mg kg和 9 95— 46 1 8mg kg .结合单污染指数评价法和表底土比较 2种方法进行污染评判 ,结果表明 ,土壤样品中重金属Cd的污染最为明显 ,其污染多集中在中度和重度水平 .对于重金属Pb、Zn和Cu的污染用单污染指数评判没有准确反映污染的真实情况 ,同时说明不同评判方法的精确性有较大的差距 .用表底土比较法对Pb、Cu、Zn 3种重金属进行评判 ,发现其在采样区域的污染水平仍非常明显 ,依次有 5 7 1 %,2 1 0 %和 5 3 3%的表土样品受到这 3种重金属不同程度的污染 .大部分受到污染的土壤样点大多集中在市内工业区附近土壤和城乡结合部菜地

虎眼万年青和其他3种抗癌中草药的微量元素含量及其溶出特性

目的对虎眼万年青和其他3种抗癌中草药(白花蛇舌草、半枝莲和山豆根)中16种常量和微量元素及溶出率进行比较,为阐明虎眼万年青抗癌作用提供依据。方法采用等离子体原子发射光谱法,辅以原子吸收光谱法和原子荧光光谱法进行有关检测。结果1)虎眼万年青含有多种人体必需的常量和微量元素,特别是Ca、Mg、Fe、Zn含量较高;2)虎眼万年青和其他3种中草药水煎液中Cu/Zn比值比较低;3)4种中草药水煎液中Se含量较低,差异无统计学意义。Ge在4种中草药的原生药或水煎液中的含量均较低。结论虎眼万年青可能通过调节肿瘤患者体内Cu、Zn及Ca等元素的平衡发挥其抗癌、抗炎性反应作用。

Synthesis, characterization and fabrication on a glassy carbon electrode of a tetra-iron substituted sandwich-type pentadecatungstodiarsenate heteropolyanion

A novel sandwich-type compound, Na-12[Fe-4(H2O)(2)(As2W15O56)2].41H(2)O, has been synthesized. The compound was well-characterized by means of IR, UV-vis, W-183 NMR and elemental analyses. The compound crystallizes in the triclinic, P (1) over bar symmetry group. The structure of the compound is similar to that of Na-16[M-4(H2O)(2)(As2W15O56)(2)].nH(2)O (M = Cu, Zn, Co, Ni, Mn, Cd), and consists of an oxo-aqua tetranuclear iron core, [(Fe4O14)-O-III(H2O)(2)], sandwiched by two trivacant alpha-Wells-Dawson structural moieties, alpha-[As2W15O56]. Redoxelectrochemistry of the compound has been studied in buffer solutions at pH = 4.7 using polarography and cyclic voltammetry ( CV). The compound exhibited four one-electron couples associated with the Fe(III) center followed by three four-electron redox processes attributed to the tungsten-oxo framework. The compound-containing monolayer and multilayer films have been fabricated on a 4-aminobenzoic acid modified glassy carbon electrode surface by alternating deposition with a quaternized poly(4-vinylpyridine) partially complexed with [Os(bpy)(2)Cl](2+/-). CV, X-ray photoelectron spectroscopy (XPS), UV-vis spectroscopy and atomic force microscopy (AFM) have been used to characterize the multilayer films.

Influence of intraperitoneal injection of rare earth compounds on the activities of antioxidant enzymes and the level of lipid peroxidation in mice livers

Following intraperitoneal injection of lanthanum and terbium chloride and their complexes of diethyltriaminopentagacetic acid (DTPA) to adult mice with a dose of 0.28 mmol/kg body weight/day for three days. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and the content of lipid end product, malonaldehyde (MDA) in the mice livers have been assayed respectively. The results show that the activity of SOD was increased and the content of MDA was reduced for LaCl3 treated mice and the two targets were not changed for TbCl3, but the activity of GSH-Px was reduced markedly for both LaCl3 and TbCl3 while the above three targets were not changed for La-DTPA and Tb-DTPA complexes.

聚(苯乙烯-4-乙烯基吡啶)钕配合物的研究

含氮聚合物是一类很有意义的配位体,它在某些反应的催化过程中起载体作用。在含氮聚合物中,聚(苯乙烯-4-乙烯基吡啶)(PS4VPY)也是一种很重要的配体,因其杂环氮原子有一定的反应能力和配位能力。聚(4VPY)过渡金属(如Co、Ni、Cu和Zn)配合物已有报道。但PS4VPY的稀土配合物未见报道。本文报道NdCl_3·PS4VPY的合成和表征,及催化活性。

电感耦合等离子体发射光谱法测定大气降水中多种元素

本文研究了长白山自然保护区大气降水（雨水或雪水）中的多元素分析。采用ICP-AES法测定水中的K、Na、Ca、Mg、Mn、Fe、Sr、Ba、Cu、Zn、Ni和V等元素，用干扰系数法对光谱干扰进行修正。为该地区天气环境背景值和大气污染现状提供了富贵资料。

Influence of several non-nutrient additives on nonspecific immunity and growth of juvenile turbot, Scophthalmus maximus L.

The effects of three non-nutrient additives on nonspecific immunity and growth of juvenile turbot (Scophthalmus maximus L.) were studied in this feeding experiment. The five treatments are basal diet alone, basal diets containing three different additives [0.4 g kg(-1) of xylo-oligosaccharides (XOS), 1.3 g kg (-1) of yeast cell wall and 0.8 g kg (-1) of bile acids] individually or in combination. Two hundred and twenty-five turbots (average initial weight 151.3 +/- 11.3 g) were randomly allotted in five treatments with three replicates within each treatment in a 72-day period. Comparing with basal diet group, activities of C3, C4, phagocyte, lysozyme, specific growth rate and feed conversion rate in yeast cell wall, XOS and the combined groups was enhanced significantly (P < 0.05); however, these parameters in bile acid groups were increased slightly (P > 0.05) except for phagocyte (P < 0.05); superoxide dismutase activity in additive groups was not significantly increased (P > 0.05) except for the combined group (P < 0.05). In conclusion, supplementation of yeast cell wall and XOS enhanced the nonspecific immunity of juvenile turbot. Synergistic or additive effect of the three additives was not observed.

cDNA cloning and gene expression pattern following bacterial challenge of peroxinectin in Chinese shrimp Fenneropenaeus chinensis

Peroxinectin, a cell-adhesive hemoperoxidase that binds superoxide dismutase and mediates blood cells adhesion and migration in invertebrate, is believed to play an important role in cellular immune reaction. In this study, we reported a new peroxinectin gene homologue from Chinese shrimp Fenneropenaeus chinensis. Based on expressed sequence tags (ESTs) of haemocyte cDNA library, we cloned a 2,611 bps full-length cDNA of peroxinectin gene homologue encoded 801 amino acids. Motif scanning of the predicted polypeptide revealed a peroxidase domain and an integrin binding motif (Lys-Gly-Asp, KGD). Peroxinectin gene expressed constitutively in haemocyte as determined by quantitative real-time RT-PCR, the expression level varied following bacterial challenge. These findings suggested that peroxinectin expression is susceptible to exterior stimulus and maintains at a high expression level during bacterial infection.

The immune responses in Chinese mitten crab Eriocheir sinensis challenged with double-stranded RNA

Double-stranded RNA (dsRNA) is a virus-associated molecular pattern which induces antiviral innate immune responses and RNA interference (RNAi) in mammals. In invertebrates, RNAi phenomenon has been widely studied, but dsRNA-induced innate immune response is seldom reported. In the present study, two different dsRNAs specific for green fluorescent protein (GFP) and the putative D1 protein of photosystem II (NoPSD) from Nannochloropsis oculata, were employed to challenge Chinese mitten crab Eriocheir sinensis. The temporal changes of phenoloxidase (PO), acid phosphatase (ACP), superoxide dismutase (SOD) and malondialdehyde (MDA) content, as well as the mRNA expression of some immune-related genes were examined in order to estimate the effect of dsRNAs on the innate immunity of E. sinensis. The activities of PO, ACP and SOD significantly increased after dsRNA treatment, whereas malondialdehyde (MDA) content did not change significantly. Among the examined genes, only the mRNA expression of EsALF, an antibacterial peptide in E. sinensis, was significantly up-regulated (about 5 fold, P < 0.05) at 12 h after dsRNA treatment, while no significant expression changes were observed among the other immune genes. The increase of PO, ACP and SOD activities, and mRNA expression level of EsALF after dsRNA stimulation indicate that phenoloxidase, hydrolytic enzyme, antioxidation and EsALF were involved in dsRNA-induced innate immunity, suggesting that broad-spectrum immune responses could be induced by dsRNA in E. sinensis. (C) 2009 Elsevier Ltd. All rights reserved.

Comparative proteomic profiles of the hepatopancreas in Fenneropenaeus chinensis response to hypoxic stress

Hypoxia, as one suboptimal environmental condition, can affect the physiological state of shrimp during pond aquaculture. To better understand the mechanism of response to hypoxic stress in Chinese shrimp Fenneropenaeus chinensis, proteome research approach was utilized. Differentially expressed proteins of hepatopancreas in adult Chinese shrimp between the control and hypoxia-stressed groups were screened. By 2-DE analysis, 67 spots showed obvious changes after hypoxia. Using LC-ESI-MS/MS, 51 spots representing 33 proteins were identified including preamylase, arginine kinase, phosphopyruvate hydratase, citrate synthase, ATP synthase alpha subunit, chymotrypsin BI, chitinase, ferritin, C-type lectin receptors, transketolase, formylglutathione hydrolase, formyltetrahydrofolate dehydrogenase, aldehyde dehydrogenase, glutathione peroxidase, cytosolic manganese superoxide dismutase, protein disulfide isomerase, beta-actin, oncoprotem nm23, crustacyanin-Cl and so on. These proteins could be functionally classified into several groups such as proteins related to energy production, metabolism-related proteins, immune-related proteins, antioxidant proteins, chaperones, cytoskeleton proteins and ungrouped proteins. The transcription levels of ten selected genes encode the identified proteins were analyzed by real-time PCR at different sampling times of hypoxia. This study is the first analysis of differentially expressed proteins in the hepatopancreas of shrimp after hypoxia and provides a new insight for further study in hypoxic stress response of shrimp at the protein level.

The enhanced immune protection of Zhikong scallop Chlamys farreri on the secondary encounter with Listonella anguillarum

It is well known that invertebrates are devoid of adaptive immune components and rely primarily on innate immunity to defend against pathogens, but recent studies have demonstrated the existence of enhanced secondary immune protection in some invertebrates. in the present study, the cumulative mortality of scallops received two successive Listonella anguillarum stimulations was recorded, and variations of immune parameters including phagocytosis (phagocytic rate and phagocytic index), phenoloxidase-like enzyme, acid phosphatase and superoxide dismutase activities were also examined. The scallops received a previous short-term L anguillarum stimulation were protected against a long-term stimulation of L. anguillarum. Significantly higher level of phagocytic activities and acid phosphatase activity were observed in the scallops received twice stimulations compared with those only received the secondary stimulation. These results indicated that a short-term immersion with L. anguillarum modulated the scallops' immune system and endowed the scallops with enhanced resistance to the secondary bacterial stimulation: phagocytosis and acid phosphatase were suspected to be involved in the protection. (C) 2008 Elsevier Inc. All rights reserved.

Relationship between differential retention of Escherichia coli and Enterococcus faecalis and variations in enzyme activity in the scallop Patinopecten yessoensis

Uptake of Escherichia coli and Enterococcus faecalis and variations of trypsin amylase activity acid phosphatase and superoxide dismutase in tissue of the scallop Patinopecten yessoensis were detected. The results showed that P. yessoensis accumulated E. faecalis in larger numbers and more rapidly than E. coli, both with the highest concentration in the digestive tract and lowest in hemolymph. Compared to E. coil, all scallops exposed to E. faecalis showed significantly higher trypsin and AMS activity. SOD activity in hemocytes and ACP activity in hemolymph was significantly higher in the treatments with 5 log(10)CFU/ml E. colt than with E. faecalis. But no significant differences in ACP activity of P. yessoensis exposed to a 3 log(10)CFU/ml inoculum of both bacteria were recorded. In conclusion, the mass retention of gut microflora in P. yessoensis is positively correlated with digestive enzymes activity and negatively correlated with ACP activity in the hemocyte. (C) 2010 Published by Elsevier Ltd.

Formation of Fe-oxyhydroxides from the East Pacific Rise near latitude 13 degrees N: Evidence from mineralogical and geochemical data

The mineralogical and geochemical characteristics of Fe-oxyhydroxide samples from one dredge station (long. 103 degrees 54.48'W, lat. 12 degrees 42.30'N, water depth 2655 m) on the East Pacific Rise near lat 13 degrees N were analyzed by XRD, ICP-AES, and ICP-MS. Most Fe-oxyhydroxides are amorphous, with a few sphalerite microlites. In comparison with Fe-oxyhydroxides from other fields, the variable ranges in the chemical composition of Fe-oxyhydroxide samples are very narrow; their Fe, Si, and Mn contents were 39.90%, 8.92%, and 1.59%, respectively; they have high Cu (0.88%-1.85%) and Co (65x10(-6)-704x10(-6)) contents, and contain Co+Cu+Zn+Ni > 1.01%. The trace-element (As, Co, Ni, Cu, Zn, Ba, Sr) and major-element (Fe, Ca, Al, Mg) contents of these samples are in the range of hydrothermal sulfide from the East Pacific Rise near 13 degrees N, reflecting that this type of Fe-oxyhydroxide constitutes a secondary oxidation product of hydrothermal sulfide. The Fe-oxyhydroxide samples from one dredge station on the East Pacific Rise near 13 degrees N are lower in Sigma REE (5.44x10(-6)-17.01x10(-6)), with a distinct negative Ce anomaly (0.12-0.28). The Fe-oxyhydroxide samples have similar chondrite-normalized rare-earth-element (REE) patterns to that of seawater, and they are very different from the REE composition characteristics of hydrothermal plume particles and hydrothermal fluids, showing that the REEs of Fe-oxyhydroxide are a major constituent of seawater and that the Fe-oxyhydroxides can become a sink of REE from seawater. The quick settling of hydrothermal plume particles resulted in the lower REE content and higher Mn content of these Fe-oxyhydroxides, which are captured in part of the V and P from seawater by adsorption. The Fe-oxyhydroxides from one dredge station on the East Pacific Rise near 13 degrees N were formed by secondary oxidation in a low temperature, oxygenated environment. In comparison with the elemental (Zn, Cd, Pb, Fe, Co, Cu) average content of hydrothermal sulfide samples from the East Pacific Rise near 13 degrees N, the Zn, Cd, and Pb contents of the Fe-oxyhydroxides are lower, and their Fe, Co, and Cu contents are higher.