Effects of Heavy Metal Ions (Cu^(2+), Pb^(2+) and Cd^(2+)) on DNA Damage of the Gills, Hemocytes and Hepatopancreas of Marine Crab, Charybdis japonica

There are rising concerns about the hazardous effects of heavy metals on the environment. In this study, comet assay and DNA alkaline unwinding assay were conducted on the tissues (gills, hepatopancreas, and hemocytes) of Charybdis japonica in order to illustrate genotoxicity of three heavy metal ions (Cu2+, Pb2+, and Cd2+) on the marine crabs C. japonica. The crabs were exposed to Cu2+ (10, 50, and 100 ?g.L?1), Pb2+ (50, 250, and 500 ?g L?1) and Cd2+ (5, 25, and 50 ?g L?1), and the tissues were sampled at days 0.5, 1, 3, 6, 9, and 15. DNA alkaline unwinding assay was used for testing the DNA single strand break in gills and hepatopancreas and comet assay was employed for testing the DNA damage in hemocytes. The results showed that the DNA damage (F-value) of gills in the crabs exposed to the three heavy metals was decreased gradually during the exposure periods and there was a dose-time response relationship in certain time, suggesting that the levels of DNA single strand break in all the experimental groups increased significantly compared to the controls. Changes of F-value in hepatopancreas of the crabs exposed to the three heavy metals were similar to those in gills except that the peak values were found in the 500 ?g L?1 Pb2+ treatment group at day 3 and the 50 ?g L?1 Cd2+ treatment group at day 9. The ranks of DNA damage in gills and hepatopancreas induced by the three heavy metal ions (50 ?g L?1, day 15) were Cd2+ >Pb2+ >Cu2+ and Pb2+ >Cu2+ >Cd2+. The levels of DNA damage in gills were higher than those in hepatopancreas in the same experimental group. It can be concluded that indices of DNA damage can be used as the potential biomarkers of heavy metal pollution in marine environment.

Adsorption of Pb, Cd to Fe, Mn oxides in natural freshwater surface coatings developed in different seasons

Metal oxides(Fe, Mn oxides) in natural surface coatings(biofilms and associated minerals) are believed to play a significant role in the fate and transport of trace metal in aquatic environments. Seasonal variation of Fe, Mn oxides and organic materials in surface coatings, which were developed periodically on glass slides in Nanhu Lake, Jilin Province, China over the time frame of three seasons, was investigated in order to understand the influence of metal oxides on Pb and Cd adsorption to heterogeneous surface coating materials(biofilm). Pb and Cd adsorption was measured under controlled laboratory conditions(mineral salts solution with defined speciation, ionic strength 0 05 mol/L, 25℃ and pH 6 0). The classical Langmuir adsorption isotherm was applied to estimate equilibrium coefficients of Pb and Cd adsorption to the surface coatings. In general, components in the surface coatings varied greatly with seasons altering and obtained higher concentrations in summer while the content of iron oxides always exceeded that of manganese oxides. Correlation analyses between the maximum adsorption of Pb and Cd and components in the surface coatings developed periodically indicated that Pb phase association with Mn oxides and Cd phase association with Fe oxides as well as Mn oxides were statistically significant. Effect of Mn oxides on Cd adsorption was confirmed in view of its higher content in the surface coatings. The importance of ferromanganese oxides for Pb and Cd adsorption to the natural surface coatings developed in different seasons was evidenced.

Identification of CD13,CD107a,and CD164 as novel basophil-activation markers and dissection of two response patterns in time kinetics of IgE-de-pendent upregulation

Using two-colour flow cytometry>200 antibodies submitted to the 8^(th) International Workshop of Human Leukocyte Differentiation Antigens(HLDA8)have been analyzed for their reactivity with resting and activated CD203c^(+)basophils.Four antibodies either non-reactive or weakly reactive with resting basophils exhibited an increased reactivity with basophils activated by anti-IgE-mediated cross-linking of the high affinity IgE receptor(FcεRI).These include antibod-ies against CD164(WS-80160,clone N6B6 and WS-80162,clone 67D2),as well as two reagents with previously unknown specificities that were identified as CD13(WS-80274,clone A8)and CD107a(WS-80280,clone E63-880).The activation patterns followed either the“CD203c-like”or“CD63-like”activation profile.The CD203c profile is characterized by a rapid and significant upregulation(of CD13,CD164,and CD203c),reaching maximum levels after 5-15 min of stimulation.The phosphoinositide-3-kinase(PI3K)-specific inhibitor wortmannin inhibited the upregulation of these markers whereas 12-O-tetradecanoyl-phorbol-13-acetate(TPA)induced a rapid and FcεRI-independent upregulation within 1-2 min.In the CD63 profile,maximum upregulation(of CD63 and CD107a)was detected only after 20-40 min,and upregulation by TPA reached maximum levels after 60 min.In summary,our data identify CD13,CD107a,and CD164 as novel basophil-activation antigens.Based on time kinetics of upregulation,we hypothesize that molecules of the“CD203c group”and the“CD63 group”are linked to two different mechanisms of basophil activation.

Effect of Pb and Cd Stress on the Growth of Potato and Its Antioxidase System

With the potato variety Xishu 1 as the test materials, this paper adopted tissue culture to study the effect of Pb and Cd stress with different mass fractions on potato growth and the antioxidase system. The results showed that under the stress of Pb （200 mg/kg） and Cd （20 mg/kg）, growth of potato had no obvious difference with that in control group; under the stress of Pb （ 〉200 mg/kg） and Cd （ 〉20 mg/kg）, potato growth suspended, and its physiological indexes such as dry weight, plant height, root number, root length were inhibited obviously. With the increasing mass fraction of Pb, relative electrical conductivity, MDA and proline of potato leaves showed the tendency of increase, and the results in high mass fraction treatments showed significant difference with those in the control group （P 〈 0.05 ）, CAT, POD and SOD activity of leaves increased greatly with the increasing mass fraction. In the Pb stress treatment （200 mg/kg）, relative electrical conductivity, MDA and proline of potato leaves showed no obvious difference with those in the control group, and the results in high mass fraction treatments were significantly higher than those in the control group （ P 〈 O. 05 ）, CAT and SOD activity increased greatly with the increasing mass fraction （ P 〈 0.05 ）. Under the stress of Pb and Cd, synthesis of soluble protein in potato leaves was strongly inhibited. The results showed that potato was tolerant to Pb and Cd of lower mass fraction, and damage of potato caused by Pb and Cd stress could be relieved by improving activity of antioxidase and reducing peroxidation of membrane lipid, and the tolerance reduced with the increase of stress.

Removal of Pb^(2+) and Cd^(2+) by adsorption on clay-solidified grouting curtain for waste landfills

Pb2+ and Cd2+ in leachate were adsorbed on clay-solidified grouting curtain for waste landfills with equilibrium experiment. The cation exchange capacity was determined with ammonium acetate. And the concentration of heavy metal cations in leachate was determined with atomic absorption spectrophotometer. Their equilibrium isotherms were measured, and the experimental isotherm data were analyzed by using Freundlich and Langmuir models. The results show that the adsorption capacities of the heavy metal cations are closely related to the compositions of clay-solidified grouting curtain, and the maximum adsorption appears at the ratio of cement to clay of 2∶4 in the experimental conditions. At their maximum adsorption and pH 5.0, the adsorption capacities of Pb 2+ and Cd 2+ are 16.19mg/g and 1.21mg/g. The competitive adsorption coefficients indicate that the adsorption of clay-solidified grouting curtain for Pb2+ is stronger than that for Cd 2+ . The adsorption process conforms to Freundlich’s model with related coefficient higher than 0.996.

Effects of Combined Pollution of Pb and Cd on Growth and Yield of Rice

[Objective] The aim was to study the damage and the mechanism of combined pollution of Pb and Cd on rice growth,yield and quality of rice. [Method]Effects of combined pollution of Pb and Cd on the growth and yield of rice were studied by pot experiment with cultivating rice. [Result] Pb and Cd could promote rice growth at low concentration while inhibit plant height at high concentration; Pb and Cd stress reduced the number of rice tillers significantly,with the increasing of stress concentration,the decrease amplitude of the number of tillers was greater; the panicle per pot,seed setting rate,1 000-grain weight and yield of rice were reduced significantly by Pb and Cd stress,the grain number per panicle decreased significantly under low concentration of Pb and Cd but increased significantly under high concentration; the brown rice rate and milled rice rate increased significantly under low concentration of Pb and Cd while at high concentration of Pb and Cd,the both two reduced significantly,the head milled rice rate reduced significantly with the decreasing of concentration; The Pb and Cd content of grains were significantly positively related to the concentrations of Pb and Cd content in soil,it had excessively exceeded hygienic standard when the concentrations of Pb and Cd in soil were medium-high and the unqualified rate reached 333% and 122%. [Conclusion]The study had provided basis for the establishment of rice cultivation system in pollution areas.

CD3ε of a pan T cell marker involved in mouse Aspergillus fumigatus keratitis

AIM:To explore whether CD3ε is involved in the adaptive immunity of Aspergillus fumigatus(A.fumigatus)keratitis in mice and the role of innate and adaptive immunity in it.METHODS:Mice models of A.fumigatus keratitis were established by intra-stromal injection and corneal epithelial scratching.Subconjunctival injections of natamycin,wedelolactone,LOX-1 inhibitor(poly I)or Dectin-1 inhibitor(laminarin)were used to treat mice with A.fumigatus keratitis.Mice were pretreated by intraperitoneal injection of anti-mouse CD3ε.We observed the corneal infection of mice under the slit lamp microscope and made a clinical score.The protein expression of CD3ε and interleukin-10(IL-10)was determined by Western blotting.RESULTS:With the disease progresses,the degree of corneal opacity and edema augmented.In the intrastromal injection models,CD3εprotein expression began to increase significantly on the 2^(nd) day.However,in the scraping epithelial method models,CD3ε only began to increase on the 3^(rd) day.After natamycin treatment,the degree of corneal inflammation in mice was significantly attenuated on the 3^(rd) day.After wedelolactone treatment,the severity of keratitis worsened.And the amount of CD3ε protein was also reduced,compared with the control group.By inhibiting LOX-1 and Dectin-1,there was no significant difference in CD3ε production compared with the control group.After inhibiting CD3ε,corneal ulcer area and clinical score increased,and IL-10 expression was downregulated.CONCLUSION:As a pan T cell marker,CD3ε participate in the adaptive immunity of A.fumigatus keratitis in mice.In our mice models,the corneas will enter the adaptive immune stage faster.By regulating IL-10,CD3ε exerts antiinflammatory and repairs effects in the adaptive immune stage.

Therapeutic polypeptides based on HBV core 18-27 epitope can induce CD_8^+ CTL-mediated cytotoxicity in HLA-A2^+ human PBMCs

AIM: To explore how to improve the immunogenicity of HBcAg CTL epitope based polypeptides and to trigger an HBV-specific HLA I-restricted CD8^+ T cell response in vitro.METHODS: A new panel of mimetic therapeutic peptides based on the immunodominant B cell epitope of HBV PreS2 18-24 region, the CTL epitope of HBcAg18-27 and the universal T helper epitope of tetanus toxoid (TT) 830-843 was designed using computerized molecular design method and synthesized by Merrifield's solid-phase peptide synthesis.Their immunological properties of stimulating activation and proliferation of lymphocytes, of inducing TN1 polarization,CD8^+ T cell magnification and HBV-specific CD8^+ CTL mediated cytotoxicity were investigated in vitro using HLA-A2^+ human peripheral blood mononuclear cells (PBMCs) from healthy donors and chronic hepatitis B patients.RESULTS: Results demonstrated that the therapeutic polypeptides based on immunodominant HBcAg18-27 CTL,PreS2 B- and universal TN epitopes could stimulate the activation and proliferation of lymphocytes, induce specifically and effectively CD8+ T cell expansion and vigorous HBVspecific CTL-mediated cytotoxicity in human PBMCs.CONCLUSION: It indicated that the introduction of immunodominant T helper plus B-epitopes with short and flexible linkers could dramatically improve the immunogenicity of short CTL epitopes in vitro.

GAS-LIQUID EQUILIBRIUM OF Pb-Cd-Zn SYSTEM UNDER VACUUM

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Compound pollution of Cd,Pb,Cu,Zn,and As on lowland rice

Cd,Pb,Cu,Zn,and As are typical pollutantsoriginated from Pb-Zn mine,smelting wastewater discharge/irrigation and gas emission,and they were distributed widely in China.Westudied the compound pollution of Cd,Pb,Cu,Zn,and As on rice. Pot culture and field plots test were bothused in the experiment.The treatments were:1)low dose:Cd 0.5,Pb 100,Cu 33,Zn 66,and As 10mg·kg;2)high dose:Cd 1.5,Pb 300,Cu 100,Zn 200,and As 30mg·kg,and 3)CK:no heavy metal was applied.Soil tested was meadow burozen(pH6.3-6.7)and the dosage of heavy metal added to the soilwas close to the soil environmental standard.Results were as follows:

Serum CD 4 4 Variant 6 as an Indicator of Tumor Burden and Metastasis in Patients with Gastric Car cinoma

Objective: To study the expression of CD44 correlation with the ability ofmetastasis of tumor cells in gastric carcinoma, to find the correlation of the concentration ofsoluble CD 44 Variant 6 (sCD44v6) and the histologic expression of CD44 Variant 6 (CD44v6) in tumorswith the clinico- pathologic features, and to make serum concentration of the CD44v6 and theexpression of CD44v6 may be useful an indicator as an early diagnosis, invasion, metastasis, andprognosis. Methods: Serum samples were obtained from 70 patients with primary gastric carcinomabefore surgery and 20 patients after surgery. Serum levels of CD44v6 were determined with aquantitative- enzyme- link-immuno- adsorbent assay. The expression of CD44v6 in tumors was examinedby immuno-histo-chemical staining. Results: Both the serum concentration of CD44v6 and itsexpression in tumors were positively related to the depth of invasion of the tumor, lymph nodemetastasis, clinical stage, and diffuse type gastric carcinoma, but not to the tumor size. The serumlevel of CD44v6 in patients with gastric cancer was significantly higher than that in control. Theserum concentration of CD44v6 was markedly lowered after curative surgery (F<0. 001), and the serumlevel of CD44v6 was higher in patients with gastric cancer with CD44v6 positive tumor cells than inthose with CD44v6 negative tumor cells. The serum level of CD44v6 was a prognostic indicator inpatients with diffuse type gastric carcinoma, as was the histological expression of CD44v6.Conclusion: CD44v6 of gastric cancer and serum concentration of CD44v6 seems to be correlated to theprogression of diffuse type gastric carcinoma metas- tasis and clinical stage. An elevated level ofsCD44v6 may serve as an indicator of lymph node metastasis (especially early metastasis) and badprognosis in pa tients with gastric carcinoma.

用淋洗法修复张士灌区Cd Pb污染沉积物的研究

采用淋洗法,以组成为0.5m ol·L-1C aC l2和0.1m ol·L-1H C l的复合药剂作为淋洗剂处理沈阳张士灌区C d、Pb污染沉积物(C d39m g·kg-1,Pb1250m g·kg-1),在pH=1.0、反应时间30m in、淋洗剂液固比3∶1、搅拌速度500r·m in-1、温度25℃的条件下,复合淋洗剂对C d和Pb的去除率分别达到70.8%和29.3%。粒级分析表明,沉积物中C d和Pb主要存在于细粒部分,因此,分级处理能够减少处理量,降低成本。一定酸度下C l-的络合作用可能是复合淋洗剂的主要强化淋洗机制。

不同类型钙化合物对污染土壤水稻吸收累积Cd Pb的影响及机理

以潮泥田和红黄泥为供试土壤,利用盆栽试验研究了施用不同类型钙化合物(CaO、CaCO3、CaSO4)对水稻吸收累积Cd、Pb的影响及机理。结果表明,潮泥田施用CaO和CaCO3后,土壤pH值明显升高。当CaO施用量达到0.36gCa·kg-1时土壤有效态Cd含量显著降低,水稻糙米Cd含量也随之显著下降,降幅达26.3%;施用CaCO(30.24gCa·kg-1)和CaSO(40.24gCa·kg-1)后水稻糙米Cd含量降幅分别为23.7%(P<0.05)和18.4%(P<0.05)。红黄泥施用CaO、CaCO3和CaSO4后,土壤pH值变化趋势与潮泥田相同。当CaO施用量达到0.24gCa·kg-1时土壤有效态Cd含量显著降低,但水稻糙米Cd含量反而上升,当CaO施用量达到0.36gCa·kg-1时,与对照相比水稻糙米Cd含量增加34.5%(P<0.05);当CaO施用量增至0.48gCa·kg-1时土壤有效态Pb含量明显增加,水稻糙米Pb含量也随之显著增加,增幅达41.7%。在等钙(0.24gCa·kg-1)条件下,潮泥田及红黄泥施用CaO、CaCO3和CaSO4后因pH变幅较小导致水稻糙米Cd、Pb含量无明显差异。综合分析认为,利用钙化合物控制污染土壤上水稻对Cd、Pb的吸收累积时,需要根据土壤Cd、Pb含量和pH综合考虑合理的钙化合物类型和用量。

Cd Pb污染对烤烟ATP酶活性及烟叶品质的影响

盆栽条件下研究了土壤中镉(Cd)、铅(Pb)污染对烟草ATP酶活性及烟叶品质的影响。结果表明,随着Cd浓度的增加,烟草根、叶中ATP酶活性逐渐降低;随着Pb浓度的增加,烟草根、叶中ATP酶活性均于150mg·kg-1时活性最大,以后均逐渐降低;ATPase活性与烟叶中烟碱和钾含量均呈显著或极显著正相关,与Cd、Pb浓度呈负相关。烟叶化学成分中,氮/碱比升高,化学成分组成趋于不协调,不利于烟叶香吃味的形成。

绿化植物废弃物对土壤中Cu Zn Pb和Cd形态的影响

利用自制的Cu、Zn、Pb和Cd污染的灰潮土和黄泥土,通过室内培养实验研究了不同绿化植物废弃物添加量和不同培养时间对这两种污染土壤中这4种重金属形态的影响。结果表明,绿化植物废弃物的加入抑制了Cu的活化,且添加60%绿化植物废弃物时有机结合态Cu的含量最高;绿化植物废弃物与污染土培养2～3个月时,残余态Zn的含量最高,对植物的毒害最小;绿化植物废弃物添加量为60%时灰潮土中有效态Pb含量较低,而添加量为30%时黄泥土中有效态Pb含量最低;绿化植物废弃物添加量的多少对灰潮土Cd形态的影响较小,但黄泥土中的Cd则随绿化植物废弃物量的增加活性逐渐减弱,且两种土壤均在培养2～3个月时可交换态Cd的含量最低。

辣椒对灰潮土重金属Cd Pb污染的反应与矿质元素吸收

通过盆栽试验和化学分析研究了辣椒对灰潮土重金属C d、Pb污染的反应与矿质元素吸收。结果表明:(1)重金属C d、Pb污染降低辣椒果实产量和果实中维生素C及糖含量,供试浓度下复合污染、C d处理和Pb处理的影响依次减弱;(2)重金属污染影响辣椒根茎叶鲜重,复合污染减少根茎叶鲜重的影响大于C d处理的影响,Pb处理的可增加根茎叶鲜重;(3)C d在辣椒体内的迁移性强于Pb的迁移性;复合污染中C d、Pb相互促进,增加植株各部C d、Pb吸收率;单一污染时,Pb对C d的吸收无促进作用,而C d可以增加辣椒各部对Pb的吸收;(4)各处理中辣椒各部Zn、K、C a含量变化趋势与C d含量变化趋势基本一致;(5)辣椒种植后,污染土壤残留的D TPA可提取态重金属量仍显著高于对照。

Cd Pb单一与复合污染对辣椒生物量及重金属残留的影响

通过盆栽试验和化学分析,研究了重金属Cd、Pb单一与复合污染对辣椒生物量及重金属残留的影响。结果表明:(1)重金属处理显著降低辣椒果实产量,复合污染处理大于Cd/Pb单独处理对辣椒果实重的影响。(2)单一重金属处理在一定程度上可促进辣椒根、茎、叶的生长,增加根冠比;重金属复合作用时,毒害作用逐渐增强。(3)辣椒对Cd的富集能力大于对Pb的富集能力,各部位对Cd、Pb的平均富集能力以根最高,果实最低;Pb一般集中在根部,难于向果实转移且根是受重金属影响最严重的器官。(4)Cd处理增加果实中Cd、Pb、Zn、K、Ca、Mg含量,显著降低Cu、Mn、Mo含量;Pb处理增加果实中Pb、Zn、Mg含量,降低K、Cu、Fe、Mn、Mo含量;复合污染处理对各元素的吸收作用有增有减,作用较为复杂。

Cd Pb复合处理下对植物膜的伤害初探

以黄瓜、小麦为试验材料 ,以 Cd,Pb复合浓度进行处理 .研究了在不同处理水平下两种植物叶片的质膜透性、丙二醛、超氧化物岐化酶和过氧化物酶活性的变化 .重点讨论了 Cd,Pb复合处理对植物膜系统的伤害机理 .结果表明 :不同的 Cd,Pb复合浓度处理后植物的膜脂过氧化作用加剧、质膜透性增高 ,复合处理条件下 Cd,Pb表现明显的相互作用 ,不同的植物及不同的浓度组合有着不同的影响 ,对植物膜系统有严重的伤害 。

Pb、Cd掺杂对GeTe材料热电性能和稳定性的改善

以GeTe合金为研究对象,通过掺杂Pb元素形成GeTe-PbTe固溶体合金,拓宽相变温区,提高材料长期工作稳定性的同时提升热电性能。为进一步提升材料热电性能,在GeTe-PbTe固溶体合金中掺杂Cd元素,通过熔炼、真空热压、退火结合工艺制备了(GeTe)_(0.91-x)(CdTe)_(x)(PbTe)_(0.09)合金系列样品,当x=0.04时,在773 K温度条件下获得最大热电优值(ZT)为1.72。测试了GeTe合金、(GeTe)_(0.91)(PbTe)_(0.09)合金、(GeTe)_(0.87)(CdTe)_(0.04)(PbTe)_(0.09)合金的工作稳定性,结果表明:同时掺杂Pb、Cd元素后,可显著提高GeTe合金的工作稳定性,与N型PbTe材料组成的温差电单偶最大输出功率年衰减率仅为3.11%。