Testing the validity of a Cd soil quality standard in representative Mediterranean agricultural soils under an accumulator crop

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Recatala, L., E-mail: luis.recatala@uv.es [Departamento de Planificacion Territorial, Centro de Investigaciones sobre Desertificacion-CIDE (CSIC-Universitat de Valencia-Generalitat Valenciana), Cami de la Marjal S/N, 46470 Albal (Valencia) (Spain); Sanchez, J. [Departamento de Planificacion Territorial, Centro de Investigaciones sobre Desertificacion-CIDE (CSIC-Universitat de Valencia-Generalitat Valenciana), Cami de la Marjal S/N, 46470 Albal (Valencia) (Spain); Arbelo, C. [Departamento de Edafologia y Geologia, Facultad de Biologia, Universidad de La Laguna, 38206 La Laguna (Tenerife), Islas Canarias (Spain); Sacristan, D. [Departamento de Planificacion Territorial, Centro de Investigaciones sobre Desertificacion-CIDE (CSIC-Universitat de Valencia-Generalitat Valenciana), Cami de la Marjal S/N, 46470 Albal (Valencia) (Spain)

2010-12-01

The validity of a quality standard for cadmium (Cd) in representative agricultural Mediterranean soils under an accumulator crop (Lactuca sativa L.) is evaluated in this work considering both its effect on the crop growth (biomass production) and the metal accumulation in the edible part of the plant. Four soils with different properties relevant to regulate the behaviour of heavy metals were selected from the Valencian Region, a representative area of the European Mediterranean Region. For all soils, the effective concentration of added Cd causing 50% inhibition (EC{sub 50}) on the biomass production was much higher than the minimum legal concentration used to declare soils as contaminated by cadmium, i.e. 100 times the baseline value for Cd, in Spain (Spanish Royal Decree 9/2005). As expected, Cd toxicity in the crop was higher in the soils having less carbonate content. On the other hand, for all soils, from the second dose on, which represents 10-times the baseline value for Cd, the metal content in crops exceeded the maximum level established for leaf crops by the European legislation (Regulation EC no. 466/2001). Soil salinity and coarse textures make the accumulation of Cd in the edible part of the plant easier. Therefore, the legal baseline soil cadmium content established by the Spanish legislation seems not valid neither from the point of view of the effect on the crop growth nor from the point of view of the metal accumulation in the edible part of the plant. In order to realistically declare contaminated soils by heavy metals, soil quality standards should be proposed taking into account the soil properties. Further research in other agricultural areas of the region would improve the basis for proposing adequate soil quality standards for heavy metals as highlighted by the European Thematic Strategy for Soil Protection.

Effects of Interaction between Cadmium (Cd) and Selenium (Se) on Grain Yield and Cd and Se Accumulation in a Hybrid Rice (Oryza sativa) System.

Science.gov (United States)

Huang, Baifei; Xin, Junliang; Dai, Hongwen; Zhou, Wenjing

2017-11-01

A pot experiment was conducted to investigate the interactive effects of cadmium (Cd) and selenium (Se) on their accumulation in three rice cultivars, which remains unclear. The results showed that Se reduced Cd-induced growth inhibition, and increased and decreased Se and Cd concentrations in brown rice, respectively. Cadmium concentrations in all tissues of the hybrid were similar to those in its male parent yet significantly lower than those in its female parent. Selenium reduced Cd accumulation in rice when Cd concentration exceeded 2.0 mg kg -1 ; however Se accumulation depended on the levels of Cd exposure. Finally, Cd had minimal effect on Se translocation within the three cultivars. We concluded that Cd concentration in brown rice is a heritable trait, making crossbreeding a feasible method for cultivating high-yield, low-Cd rice cultivars. Selenium effectively decreased the toxicity and accumulation of Cd, and Cd affected Se uptake but not translocation.

Comparison Of Cd And Zn Accumulation In Tissues Of Different Vascular Plants: A Radiometric Study

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Dürešová Zuzana

2015-12-01

Full Text Available The aim of the present work was to compare the accumulation and translocation of Cd and Zn in plants of tobacco (Nicotiana tabacum L., celery (Apium graveolens L., maize (Zea mays L., giant reed (Arundo donax L., and alpine pennycress (Noccaea caerulescens L. under conditions of short-term hydroponic experiments using nutrient solutions spiked with radionuclides 109Cd or 65Zn, and direct gamma-spectrometry. It was found that the time-course of metals accumulation in studied plants was not different in terms of target metal, but it was significantly different on the level of plant species. The highest values of Cd accumulation showed plants of giant reed, whereby the accumulation decreased in the order: giant reed > tobacco > alpine pennycress >> maize and celery. On the basis of concentration ratios (CR [Me]shoot / [Me]root calculation for both metals, it was found that Cd and Zn were in prevailing part accumulated in the root tissues and only partially accumulated in the shoots, where the amount of accumulated Cd and Zn increased from the oldest developed leaves to the youngest developed leaves. The CR values corresponding to these facts were calculated in the range 0.06 – 0.27 for Cd and for Zn 0.06 – 0.48. In terms of plant species, the CR values obtained for Cd decreased in the order: maize > celery > tobacco and giant reed > alpine pennycress. The similarity between studied objects – individual plant species on the basis of the obtained variables defining Cd or Zn accumulation at different conditions of the experiments as well as the relationships between obtained variables and conditions of the experiments were subjected to multivariate analysis method – cluster analysis (CA. According to the findings and this analysis, it can be expected that plants of tobacco and giant reed will dispose with similar characteristics as plants of alpine pennycress, which are classified as Zn/Cd hyperaccumulators, in terms of Cd or Zn accumulation

Cadmium accumulation, gill Cd binding, acclimation, and physiological effects during long term sublethal Cd exposure in rainbow trout

Energy Technology Data Exchange (ETDEWEB)

Hollis, L.; McGeer, J.C.; McDonald, D.G.; Wood, C.M. [Department of Biology, McMaster University, Hamilton, Ontario (Canada)

1999-07-01

Juvenile rainbow trout, on 3% of body weight daily ration, were exposed to 0 (control), 3, and 10 {mu}g l{sup -1} Cd (as Cd(NO{sub 3}){sub 2} {center_dot} 4H{sub 2}O) in moderately hard (140 mg l{sup -1} as CaCO{sub 3}), alkaline (95 mg l{sup -1} as CaCO{sub 3}, pH 8.0) water for 30 days. Particular attention focused on acclimation, and on whether a gill surface binding model, originally developed in dilute softwater, could be applied in this water quality to fish chronically exposed to Cd. Only the higher Cd concentration caused mortality (30%, in the first few days). The costs of acclimation, if any, in our study were subtle since no significant effects of chronic Cd exposure were seen in growth rate, swimming performance (stamina and U{sub Crit}), routine O{sub 2} consumption, or whole body ion levels. Substantial acclimation occurred in both exposure groups, manifested as 11- to 13-fold increases in 96-h LC{sub 50} values. In water quality regulations, which are based on toxicity tests with non-acclimated fish only, this remarkable protective effect of acclimation is not taken into account. Cd accumulated in a time- and concentration-dependent fashion to 60-120x (gills), 8-20x (liver), 2-7x (carcass), and 5-12x (whole bodies) control levels by 30 days. Chronically accumulated gill Cd could not be removed by ethylenediaminetetraacetic acid (EDTA) challenge. These gill Cd concentrations were 20- to 40-fold greater than levels predicted by the gill-binding model to cause mortality during acute exposure. In short-term gill Cd-binding experiments (up to 70 {mu}g l{sup -1} exposures for 3 h), gill Cd burden increased as predicted in control fish, but was not detectable against the high background concentrations in acclimated fish. In light of these results, Cd uptake/turnover tests were performed using radioactive {sup 109}Cd to improve sensitivity. With this approach, a small saturable binding component was seen, but could not be related to toxic response in

Cadmium accumulation, gill Cd binding, acclimation, and physiological effects during long term sublethal Cd exposure in rainbow trout

International Nuclear Information System (INIS)

Hollis, L.; McGeer, J.C.; McDonald, D.G.; Wood, C.M.

1999-01-01

Juvenile rainbow trout, on 3% of body weight daily ration, were exposed to 0 (control), 3, and 10 μg l -1 Cd (as Cd(NO 3 ) 2 · 4H 2 O) in moderately hard (140 mg l -1 as CaCO 3 ), alkaline (95 mg l -1 as CaCO 3 , pH 8.0) water for 30 days. Particular attention focused on acclimation, and on whether a gill surface binding model, originally developed in dilute softwater, could be applied in this water quality to fish chronically exposed to Cd. Only the higher Cd concentration caused mortality (30%, in the first few days). The costs of acclimation, if any, in our study were subtle since no significant effects of chronic Cd exposure were seen in growth rate, swimming performance (stamina and U Crit ), routine O 2 consumption, or whole body ion levels. Substantial acclimation occurred in both exposure groups, manifested as 11- to 13-fold increases in 96-h LC 50 values. In water quality regulations, which are based on toxicity tests with non-acclimated fish only, this remarkable protective effect of acclimation is not taken into account. Cd accumulated in a time- and concentration-dependent fashion to 60-120x (gills), 8-20x (liver), 2-7x (carcass), and 5-12x (whole bodies) control levels by 30 days. Chronically accumulated gill Cd could not be removed by ethylenediaminetetraacetic acid (EDTA) challenge. These gill Cd concentrations were 20- to 40-fold greater than levels predicted by the gill-binding model to cause mortality during acute exposure. In short-term gill Cd-binding experiments (up to 70 μg l -1 exposures for 3 h), gill Cd burden increased as predicted in control fish, but was not detectable against the high background concentrations in acclimated fish. In light of these results, Cd uptake/turnover tests were performed using radioactive 109 Cd to improve sensitivity. With this approach, a small saturable binding component was seen, but could not be related to toxic response in acclimated fish. Acclimated trout internalized less 109 Cd than control fish, but

Variations in cadmium accumulation among Chinese cabbage cultivars and screening for Cd-safe cultivars

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Liu Weitao; Zhou Qixing; An Jing; Sun Yuebing; Liu Rui

2010-01-01

Variations in cadmium accumulation and translocation among 40 Chinese cabbage cultivars were studied to identify and screen out Cd-safe cultivars (CSCs), i.e. cultivars with low enough accumulation of Cd in their edible parts even when grown in contaminated soils. It was observed in the pot-culture experiment that there was a significant difference (p < 0.05) in shoot Cd concentrations under three Cd treatments (1.0, 2.5 and 5.0 mg/kg), with corresponding average values 0.88, 4.45 and 7.76 mg/kg, respectively. Shoot Cd concentrations in 16 cabbage cultivars were lower than 0.50 mg/kg. The translocation factors (TFs) and the extraction factors (EFs) in five cabbage cultivars were lower than 1.0 in the pot-culture experiment. The field-culture experiment further validated that New Beijing 3 and Fengyuanxin 3 could be considered as CSCs. In particular, the two cultivars can be cultivated in low to moderate Cd-contaminated soils (Cd concentration <1.25 mg/kg) to minimize the Cd accumulation in the food.

Root anatomy and element distribution vary between two Salix caprea isolates with different Cd accumulation capacities

International Nuclear Information System (INIS)

Vaculík, Marek; Konlechner, Cornelia; Langer, Ingrid; Adlassnig, Wolfram; Puschenreiter, Markus; Lux, Alexander; Hauser, Marie-Theres

2012-01-01

The understanding of the influence of toxic elements on root anatomy and element distribution is still limited. This study describes anatomical responses, metal accumulation and element distribution of rooted cuttings of Salix caprea after exposure to Cd and/or Zn. Differences in the development of apoplastic barriers and tissue organization in roots between two distinct S. caprea isolates with divergent Cd uptake and accumulation capacities in leaves might reflect an adaptive predisposition based on different natural origins. Energy-dispersive X-ray spectroscopy (EDX) revealed that Cd and Zn interfered with the distribution of elements in a tissue- and isolate-specific manner. Zinc, Ca, Mg, Na and Si were enriched in the peripheral bark, K and S in the phloem and Cd in both vascular tissues. Si levels were lower in the superior Cd translocator. Since the cuttings originated from stocks isolated from polluted and unpolluted sites we probably uncovered different strategies against toxic elements. - Highlights: ► We describe responses in roots of S. caprea exposed to Cd and Zn. ► Apoplastic barrier development varied among isolates from differently polluted sites. ► EDX analyses revealed variations of element distributions in root tissues. ► Si weight% was lower in the isolate with a higher Cd translocation capacity. ► S. caprea isolates possessed different strategies to respond to Cd and Zn. - S. caprea altered element distribution and translocation, apoplastic barrier development and root anatomy upon Cd and/or Zn exposure.

Engineering metal-binding sites of bacterial CusF to enhance Zn/Cd accumulation and resistance by subcellular targeting

International Nuclear Information System (INIS)

Yu, Pengli; Yuan, Jinhong; Zhang, Hui; Deng, Xin; Ma, Mi; Zhang, Haiyan

2016-01-01

Highlights: • mCusF is specifically targeted to different subcellular compartments in Arabidopsis. • Plants expressing vacuole-targeted mCusF exhibit strongest Zn resistance. • All transgenic lines accumulate more Zn under Zn exposure. • All transgenic lines enhance root-to-shoot translocation of Cd. • Metal homeostasis is improved in mCusF plants under Cd exposure. - Abstract: The periplasmic protein CusF acts as a metallochaperone to mediate Cu resistance in Escherichia coli. CusF does not contain cysteine residues and barely binds to divalent cations. Here, we addressed effects of cysteine-substitution mutant (named as mCusF) of CusF on zinc/cadmium (Zn/Cd) accumulation and resistance. We targeted mCusF to different subcellular compartments in Arabidopsis. We found that plants expressing vacuole-targeted mCusF were more resistant to excess Zn than WT and plants with cell wall-targeted or cytoplasmic mCusF. Under long-term exposure to excess Zn, all transgenic lines accumulated more Zn (up to 2.3-fold) in shoots than the untransformed plants. Importantly, plants with cytoplasmic mCusF showed higher efficiency of Zn translocation from root to shoot than plants with secretory pathway-targeted-mCusF. Furthermore, the transgenic lines exhibited enhanced resistance to Cd and significant increase in root-to-shoot Cd translocation. We also found all transgenic plants greatly improved manganese (Mn) and iron (Fe) homeostasis under Cd exposure. Our results demonstrate heterologous expression of mCusF could be used to engineer a new phytoremediation strategy for Zn/Cd and our finding also deepen our insights into mechanistic basis for relieving Cd toxicity in plants through proper root/shoot partitioning mechanism and homeostatic accumulation of Mn and Fe.

Engineering metal-binding sites of bacterial CusF to enhance Zn/Cd accumulation and resistance by subcellular targeting

Energy Technology Data Exchange (ETDEWEB)

Yu, Pengli; Yuan, Jinhong [Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China); Zhang, Hui [Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China); Deng, Xin [Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637 (United States); Ma, Mi [Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China); Zhang, Haiyan, E-mail: hyz@ibcas.ac.cn [Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China)

2016-01-25

Highlights: • mCusF is specifically targeted to different subcellular compartments in Arabidopsis. • Plants expressing vacuole-targeted mCusF exhibit strongest Zn resistance. • All transgenic lines accumulate more Zn under Zn exposure. • All transgenic lines enhance root-to-shoot translocation of Cd. • Metal homeostasis is improved in mCusF plants under Cd exposure. - Abstract: The periplasmic protein CusF acts as a metallochaperone to mediate Cu resistance in Escherichia coli. CusF does not contain cysteine residues and barely binds to divalent cations. Here, we addressed effects of cysteine-substitution mutant (named as mCusF) of CusF on zinc/cadmium (Zn/Cd) accumulation and resistance. We targeted mCusF to different subcellular compartments in Arabidopsis. We found that plants expressing vacuole-targeted mCusF were more resistant to excess Zn than WT and plants with cell wall-targeted or cytoplasmic mCusF. Under long-term exposure to excess Zn, all transgenic lines accumulated more Zn (up to 2.3-fold) in shoots than the untransformed plants. Importantly, plants with cytoplasmic mCusF showed higher efficiency of Zn translocation from root to shoot than plants with secretory pathway-targeted-mCusF. Furthermore, the transgenic lines exhibited enhanced resistance to Cd and significant increase in root-to-shoot Cd translocation. We also found all transgenic plants greatly improved manganese (Mn) and iron (Fe) homeostasis under Cd exposure. Our results demonstrate heterologous expression of mCusF could be used to engineer a new phytoremediation strategy for Zn/Cd and our finding also deepen our insights into mechanistic basis for relieving Cd toxicity in plants through proper root/shoot partitioning mechanism and homeostatic accumulation of Mn and Fe.

Comparison of sup(115m)Cd accumulation from sediments and sea water by polychaete worms

International Nuclear Information System (INIS)

Ueda, Taishi; Nakamura, Ryoichi; Suzuki, Yuzuru

1976-01-01

To know the role played by marine sediments in influencing the fate of discharged metals, (1) the interaction of metals between sediments and deposit-feeder marine worms (Nereis japonica), and (2) uptake and excretion of metals by worms were examined by laboratory experiments using sup(115m)Cd. Worms directly in contact with sup(115m)Cd-sediments accumulated sup(115m)Cd six times more than worms that were not in contact with the sup(115m)Cd sediments during the 8 days of experimentation and 12% of sup(115m)Cd in sediments were noted to be transfered to worms per unit. Comparing the concentration factor of 22 (from sea water) with accumulation from sediments, it was assumed that sup(115m)Cd in sediments would give the effect of 1/200 to the accumulation of sup(115m)Cd by worms in sea water to the accumulation of sup(115m)Cd. Further, to simulate these results close to that occuring in the natural ecosystem, the distribution of sup(115m)Cd in sea water, sediments and alga were also examined by means of a curve analysis of the distribution pattern by a three compartment model. It proved that the activity ratios of sup(115m)Cd were 9 for sediments and 21 for alga, which was similar to 22 for worms. (auth.)

Cd Toxicity and Accumulation in Rice Plants Vary with Soil Nitrogen Status and Their Genotypic Difference can be Partly Attributed to Nitrogen Uptake Capacity

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Qin DU

2009-12-01

Full Text Available Two indica rice genotypes, viz. Milyang 46 and Zhenshan 97B differing in Cd accumulation and tolerance were used as materials in a hydroponic system consisting of four Cd levels (0, 0.1, 1.0 and 5.0 µmol/L and three N levels (23.2, 116.0 and 232.0 mg/L to study the effects of nitrogen status and nitrogen uptake capacity on Cd accumulation and tolerance in rice plants. N-efficient rice genotype, Zhenshan 97B, accumulated less Cd and showed higher Cd tolerance than N-inefficient rice genotype, Milyang 46. There was consistency between nitrogen uptake capacity and Cd tolerance in rice plants. Increase of N level in solution slightly increased Cd concentration in shoots but significantly increased in roots of both genotypes. Compared with the control at low N level, Cd tolerance in both rice genotypes could be significantly enhanced under normal N level, but no significant difference was observed between the Cd tolerances under normal N (116.0 mg/L and high N (232.0 mg/L conditions. The result proved that genotypic differences in Cd accumulation and toxicity could be, at least in part, attributed to N uptake capacity in rice plants.

Accumulation of Cd in Indian mustard and sunflower for phytoremediation

International Nuclear Information System (INIS)

Okada, Satoshi; Fukutani, Satoshi; Takahashi, Tomoyuki; Fukui, Masami

2004-01-01

Phytoremediation is a new method that uses plants to remove contaminants from soil without affecting soil fertility. It can therefore be used for contaminated agricultural land. Indian mustard (Brassica juncea) and sunflower (Helianthus annuus L.) are used in phytoremediation to remove Cadmium (Cd), which they can accumulate in large quantities. It is important to know when plants have accumulated significant Cd, so that we can decide when the plants should be harvested and synthetic chelates applied. Brassica juncea seeds and Helianthus annuus L. seeds were planted in a field in Kyoto University Research Reactor Institute (KUR). Brassica juncea and Helianthus annuus L. were collected at time intervals ranging from 1 to 6 months and 2 to 7 weeks, respectively, after seedling emergence and the concentration of Cd in the plants was analyzed. These results indicated that Brassica juncea should be harvested before beginning flowering and Helianthus annuus L. should be harvested after it becomes old enough. The solubility of Cd in soil is enhanced when the soil is heated or dried, and black vinyl mulch was therefore used to absorb the heat from sunlight. The difference in the Cd uptake of Brassica juncea between mulching cultivation and non-mulching cultivation was investigated in a field, and this indicated that there is no probability that mulching enhances Cd uptake in plants. The solubility of Cd in soil decreases over time. Repeated pot experiments were done. We planted Brassica juncea in pots, and investigated the uptake of Cd and the solid phase fractions in which Cd was present in each pot experiment. These did not change considerably over time, indicating that age has a negligible effect on Cd uptake in plants. (author)

A newly found cadmium accumulator-Taraxacum mongolicum

International Nuclear Information System (INIS)

Wei Shuhe; Zhou Qixing; Mathews, Shiny

2008-01-01

Identification of hyperaccumulator and accumulator is still key step of phytoextracting-contaminated soils by heavy metals. In a former published experiment, Taraxacum mongolicum showed basic characteristics of hyperaccumulators. In order to confirm if this plant was a Cd-hyperaccumulator, concentration gradient experiment and sample-analyzing experiments were designed and performed. The results showed that Cd enrichment factor and Cd transformation factor of T. mongolicum were all higher than 1 in concentration gradient experiment. The shoot biomasses did not reduced significantly (p -1 Cd spiked into soil. However, Cd concentration in shoot of T. mongolicum was not higher than 100 mg kg -1 the minimum a Cd-hyperaccumulator should have under the conditions of any concentration level of Cd spiked. Thus, T. mongolicum should be a Cd-accumulator. In the sample-analyzing experiments settled in a Pb-Zn mine area and Shenyang wastewater irrigation region, T. mongolicum also showed that Cd-accumulator characteristics. Based on these results, T. mongolicum could be identified as a Cd-accumulator, which may have important implication in plant physiology and gene engineering

Screening for Cd-Safe Cultivars of Chinese Cabbage and a Preliminary Study on the Mechanisms of Cd Accumulation

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Jingjie Wang

2017-04-01

Full Text Available With the rapid progress of industrialization, the effects of environmental contamination on plant toxicity, and subsequently on human health, is a growing concern. For example, the heavy metal pollution of soil such as that caused by cadmium (Cd is a serious threat. Therefore, screening for pollution-safe edible plants is an essential approach for growing plants under heavy metal-contaminated soils. In the current study, 35 Chinese cabbage (Brassica pekinensis L. cultivars were selected with the aim of screening for Cd-safe cultivars (CSCs, analyzing their safety, and exploring the mechanism of Cd accumulation. Our field-culture experiments revealed that the Cd content in the edible parts of the cultivars were varied and were determined to possibly be CSCs. Hydroponics experiments were used to simulate six different degrees of soil contamination (high and low Cd concentrations on possible CSCs. The results indicated a significant difference (p < 0.05 in Cd concentration in the cultivars, and verified the safety of these possible CSCs. The analyses of the transport coefficient and expression levels showed that the differences in Cd accumulation among the Chinese cabbage cultivars were related to the expression of genes involved in absorption and transport rather than a root-to-shoot translocation limitation.

Responses of different water spinach cultivars and their hybrid to Cd, Pb and Cd-Pb exposures.

Science.gov (United States)

Xin, Junliang; Huang, Baifei; Yang, Zhongyi; Yuan, Jiangang; Dai, Hongwen; Qiu, Qiu

2010-03-15

A pot experiment was conducted to investigate the stability of Cd and/or Pb accumulation in shoot of Cd and Pb pollution-safe cultivars (PSCs), the hereditary pattern of shoot Cd accumulation, and the transfer potentials of Cd and Pb in water spinach (Ipomoea aquatica Forsk.). A typical Cd-PSC, a typical non-Cd-PSC (Cd accumulative cultivar), a hybrid from the former two cultivars, and two typical Cd+Pb-PSCs were grown in seven soils with different concentrations of Cd and Pb. The results showed that concentrations of Cd and Pb in shoot of the PSCs were always lower than the non-PSC and the highest Cd and Pb transfer factors were also always observed in the non-PSC, indicating the stability of the PSCs in Cd and Pb accumulation. Shoot Cd concentration seemed to be controlled by high Cd dominant gene(s) and thus crossbreeding might not minimize Cd accumulation in water spinach. Interaction between Cd and Pb in soils affected the accumulations of the metals in shoot of water spinach. Under middle Cd and Pb treatments, the presence of higher Pb promoted the accumulation of Cd. However, under high Pb treatment, accumulations of Cd and Pb were both restricted. (c) 2009 Elsevier B.V. All rights reserved.

Mitigation of Cd accumulation in paddy rice (Oryza sativa L.) by Fe fertilization.

Science.gov (United States)

Chen, Zhe; Tang, Ye-Tao; Yao, Ai-Jun; Cao, Jian; Wu, Zhuo-Hao; Peng, Zhe-Ran; Wang, Shi-Zhong; Xiao, Shi; Baker, Alan J M; Qiu, Rong-Liang

2017-12-01

Cadmium uptake in rice is believed to be mediated by the Fe transport system. Phyto-available Cd can be changed by Fe fertilization of substrates. This work investigated whether and how Fe fertilization affects mitigation of Cd accumulation in paddy rice. A 90-d soil column experiment was conducted to study the change of Cd and Fe availability in soil after Fe fertilization (ionic and chelated Fe). A low-Cd accumulating cultivar (TY116) and a high-Cd accumulating cultivar (JY841) were grown in two Cd-polluted paddy soils amended with chelated Fe fertilizers. Additionally, both cultivars were grown in hydroponics to compare Fe-related gene expression in EDDHAFe-deficient and EDDHAFe-sufficient roots. The column experiment showed that EDTANa 2 Fe(II) and EDDHAFe(III) fertilization had a better mitigation effect on soil Cd availability compared to FeSO 4 ·7H 2 O. Moreover, the field experiment demonstrated that these two chelated fertilizations could reduce Cd concentrations in brown rice by up to 80%. Iron concentrations in the brown rice were elevated by Fe chelates. Compared to EDDHAFe(III), EDTANa 2 Fe(II) fertilization had a stronger mitigation effect by generating more EDTANa 2 Cd(II) in the soil solution to decrease phyto-available Cd in the soil. While EDDHAFe(III) fertilization could increase soil pH and decrease soil Eh which contributed to decreasing phyto-available Cd in a contaminated soil. In the hydroponic experiment, Fe sufficiency significantly reduced Cd concentrations in above-ground organs. In some cases, the expression of OsIRT1, OsNRAMP1 and OsNRAMP5 was inhibited under Fe sufficiency relative to Fe deficiency conditions. These results suggest that mitigation of rice Cd by Fe chelate fertilization results from a decrease in available Cd in substrates and the inhibition of the expression of several Fe-related genes in the IRT and NRAMP families. Copyright © 2017 Elsevier Ltd. All rights reserved.

β-Amyloid promotes accumulation of lipid peroxides by inhibiting CD36-mediated clearance of oxidized lipoproteins

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Khan Tayeba

2004-11-01

Full Text Available Abstract Background Recent studies suggest that hypercholesterolemia, an established risk factor for atherosclerosis, is also a risk factor for Alzheimer's disease. The myeloid scavenger receptor CD36 binds oxidized lipoproteins that accumulate with hypercholesterolemia and mediates their clearance from the circulation and peripheral tissues. Recently, we demonstrated that CD36 also binds fibrillar β-amyloid and initiates a signaling cascade that regulates microglial recruitment and activation. As increased lipoprotein oxidation and accumulation of lipid peroxidation products have been reported in Alzheimer's disease, we investigated whether β-amyloid altered oxidized lipoprotein clearance via CD36. Methods The availability of mice genetically deficient in class A (SRAI & II and class B (CD36 scavenger receptors has facilitated studies to discriminate their individual actions. Using primary microglia and macrophages, we assessed the impact of Aβ on: (a cholesterol ester accumulation by GC-MS and neutral lipid staining, (b binding, uptake and degradation of 125I-labeled oxidized lipoproteins via CD36, SR-A and CD36/SR-A-independent pathways, (c expression of SR-A and CD36. In addition, using mice with targeted deletions in essential kinases in the CD36-signaling cascade, we investigated whether Aβ-CD36 signaling altered metabolism of oxidized lipoproteins. Results In primary microglia and macrophages, Aβ inhibited binding, uptake and degradation of oxidized low density lipoprotein (oxLDL in a dose-dependent manner. While untreated cells accumulated abundant cholesterol ester in the presence of oxLDL, cells treated with Aβ were devoid of cholesterol ester. Pretreatment of cells with Aβ did not affect subsequent degradation of oxidized lipoproteins, indicating that lysosomal accumulation of Aβ did not disrupt this degradation pathway. Using mice with targeted deletions of the scavenger receptors, we demonstrated that Aβ inhibited oxidized

Zinc and cadmium accumulation and tolerance in populations of Sedum alfredii

International Nuclear Information System (INIS)

Deng, D.M.; Shu, W.S.; Zhang, J.; Zou, H.L.; Lin, Z.; Ye, Z.H.; Wong, M.H.

2007-01-01

To investigate the variation of Zn and Cd accumulation and tolerance of Sedum alfredii (a newly reported Zn/Cd hyperaccumulator), field surveys and hydroponic experiments were conducted among three populations of this species: two originating from old Pb/Zn mines in Zhejiang (ZJ) and Hunan (HN) Provinces and one from a 'clean' site in Guangdong (GD) Province, China. Under field conditions, up to 12,524 and 12,253 mg kg -1 Zn, and 1400 and 97 mg kg -1 Cd in shoots of ZJ and HN plants were recorded respectively. Under hydroponic conditions, ZJ and HN plants accumulated significantly higher Zn and Cd in their leaves and stems, and possessed significantly higher Zn and Cd tolerance than GD plants. Among the two contaminated populations, ZJ plants showed higher Cd tolerance and accumulation (in leaves) than HN plants. The present results indicate that significant differences in Zn and Cd accumulation and tolerance exist in populations of S. alfredii. - Marked variation of Zn and Cd tolerance and accumulation exist in populations of Sedum alfredii, a Zn/Cd hyperaccumulator

Ageing combines CD4 T cell lymphopenia in secondary lymphoid organs and T cell accumulation in gut associated lymphoid tissue.

Science.gov (United States)

Martinet, Kim Zita; Bloquet, Stéphane; Bourgeois, Christine

2014-01-01

CD4 T cell lymphopenia is an important T cell defect associated to ageing. Higher susceptibility to infections, cancer, or autoimmune pathologies described in aged individuals is thought to partly rely on T cell lymphopenia. We hypothesize that such diverse effects may reflect anatomical heterogeneity of age related T cell lymphopenia. Indeed, no data are currently available on the impact of ageing on T cell pool recovered from gut associated lymphoid tissue (GALT), a crucial site of CD4 T cell accumulation. Primary, secondary and tertiary lymphoid organs of C57BL/6 animals were analysed at three intervals of ages: 2 to 6 months (young), 10 to 14 months (middle-aged) and 22 to 26 months (old). We confirmed that ageing preferentially impacted CD4 T cell compartment in secondary lymphoid organs. Importantly, a different picture emerged from gut associated mucosal sites: during ageing, CD4 T cell accumulation was progressively developing in colon and small intestine lamina propria and Peyer's patches. Similar trend was also observed in middle-aged SJL/B6 F1 mice. Interestingly, an inverse correlation was detected between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria of C57BL/6 mice whereas no increase in proliferation rate of GALT CD4 T cells was detected. In contrast to GALT, no CD4 T cell accumulation was detected in lungs and liver in middle-aged animals. Finally, the concomitant accumulation of CD4 T cell in GALT and depletion in secondary lymphoid organs during ageing was detected both in male and female animals. Our data thus demonstrate that T cell lymphopenia in secondary lymphoid organs currently associated to ageing is not sustained in gut or lung mucosa associated lymphoid tissues or non-lymphoid sites such as the liver. The inverse correlation between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria and the absence of overt proliferation in GALT suggest that marked CD4 T cell decay in secondary

Investigation of Cd Adsorption and Accumulation from Contaminated Soil in Different Parts of Root Crops

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Bahman Yargholi

2010-01-01

    Environmental pollution with heavy metals and their absorption by plants form a universal problem around the world. Numerous investigations have been conducted to put wastewaters containing heavy metals to agricultural reuse. Little is known, however, about the absorption of cadmium in the root zone and its accumulation in the different organs of crops, particularly in root crops. This study was carried out to investigate the influence of different levels of Cd concentration in the root zone on the accumulation rate in various parts of four different types of common root crops in karaj Iran. The experiment was performed in a factorial testing plan in random blocks and in four treatments with three replicates. The treatments included four levels of Cd concentration in soil (50 mg/kg, 100 mg/kg, 50 mg/kg, control without Cd addition and water with 0.5 molar of EDTA. The soil used in this study was prepared by passing through a sieve with a 2mm mesh and adding Nitrate Cadmium (Cd(NO32. Cylinder plastic vases 40 Cm in diameter and 60 cm high were employed to cultivate vegetables. Water demandwas estimated via the Penman-Mantith method, in which Kc was calculated by means of recorded data at Meshgin-Abad synoptic station in Karaj. At the end of the growing season, samples were taken from different organs of the plants to measure Cadmium accumulation. The SPSS software was used for the variance analysis of the collected data. The Dunkan test (at 0.01 and 0.05 levels was then used to evaluate averages of the specifications in the factorial testing levels. The results indicate a direct relationship between Cd concentration in the root zone and Cd accumulation in plant organs. Adding 0.5 molar of EDTA to the irrigation water caused Cd accumulation in plant organs to exceed 60 percent. The results also show that Cd concentration, except for the control, was in excess of the limit for human consumption and that its accumulation levels in the different species tested

Cd and Ni transport and accumulation in the halophyte Sesuvium portulacastrum: implication of organic acids in these processes

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Tahar eGhnaya

2015-03-01

Full Text Available The implication of organic acids in Cd and Ni translocation was studied in the halophyte species Sesuvium portulacastrum. Citric, fumaric, malic and ascorbic acids were separated and quantified by HPLC technique in shoots, roots and xylem saps of plants grown on nutrient solutions added with 50 µM Cd, 100 µM Ni and the combination of 50 µM Cd + 100 µM Ni. Results showed that Cd had no significant impact on biomass production while Ni and the combination of both metals drastically affected plant development. Cadmium and Ni concentrations in tissues and xylem sap were higher in plants individually exposed to heavy metal application than in those subjected to the combined treatment Cd + Ni, suggesting a possible competition between these metals for absorption. Both metals applied separately or in combination induced an increase in citrate concentration in shoots and xylem sap but a decrease of this concentration in the roots. However a minor relationship was observed between metal application and fumaric, malic and ascorbic acids. Both observations suggest the implication of citric acid in Cd, Ni translocation and shoot accumulation in S. portulacastrum. The relatively high accumulation of citric acid in xylem sap and shoot of S. portulacastrum could be involved in metal chelation and thus contributes to heavy metal tolerance in this species.

[Hypertrophic cardiomyopathy showing no 123I-BMIPP myocardial accumulation with type I CD36 deficiency].

Science.gov (United States)

Watanabe, K; Miyajima, S; Kusano, Y; Tanabe, N; Hirokawa, Y

1997-07-01

A 57 years old male consulted our hospital in complaining chest oppression and short of breath. Familial and dilated phase hypertrophic cardiomyopathy (HCM) was detected by ECG, echocardiography, left ventriculography and left ventricular endomyocardial biopsy. 201T1 SPECT showed regional increased accumulation in the ventricular septum, however, no myocardial accumulation of 123I-beta-methyl-p-iodophenylpentadecanoic acid (123I-BMIPP) was observed. We analyzed CD36 in this patient, and found he had type 1 CD36 deficiency. Myocardial uptake of long-chain fatty acids occurs via a specific transporter, which is homologous with human CD36. We hypothesize that CD36 deficiency, especially type 1 CD36 deficiency, might be one factor of no myocardial 123I-BMIPP uptake.

Micro-PIXE studies of elemental distribution in Cd-accumulating Brassica juncea L

International Nuclear Information System (INIS)

Schneider, Thorsten; Haag-Kerwer, Angela; Maetz, Mischa; Niecke, Manfred; Povh, Bogdan; Rausch, Thomas; Schuessler, Arthur

1999-01-01

Brassica juncea L. is a high biomass producing crop plant, being able to accumulate Cd and other heavy metals in their roots and shoots. It is a good candidate for efficient phytoextraction of heavy metals - such as Cd - from polluted soils. PIXE and STIM analyses were applied to investigate Cd-uptake in roots and the resulting effects on the elemental distribution of Cd stressed plants. The axial distribution of trace elements as a function of distance from the root tip as well as the radial distribution within cross-sections were analysed. The results are compared with the elemental distribution in control plants

Micro-PIXE studies of elemental distribution in Cd-accumulating Brassica juncea L.

Science.gov (United States)

Schneider, Thorsten; Haag-Kerwer, Angela; Maetz, Mischa; Niecke, Manfred; Povh, Bogdan; Rausch, Thomas; Schüßler, Arthur

1999-10-01

Brassica juncea L. is a high biomass producing crop plant, being able to accumulate Cd and other heavy metals in their roots and shoots. It is a good candidate for efficient phytoextraction of heavy metals - such as Cd - from polluted soils. PIXE and STIM analyses were applied to investigate Cd-uptake in roots and the resulting effects on the elemental distribution of Cd stressed plants. The axial distribution of trace elements as a function of distance from the root tip as well as the radial distribution within cross-sections were analysed. The results are compared with the elemental distribution in control plants.

Micro-PIXE studies of elemental distribution in Cd-accumulating Brassica juncea L

Energy Technology Data Exchange (ETDEWEB)

Schneider, Thorsten E-mail: thorsten.schneider@mpi-hd.mpg.de; Haag-Kerwer, Angela; Maetz, Mischa; Niecke, Manfred; Povh, Bogdan; Rausch, Thomas; Schuessler, Arthur

1999-09-02

Brassica juncea L. is a high biomass producing crop plant, being able to accumulate Cd and other heavy metals in their roots and shoots. It is a good candidate for efficient phytoextraction of heavy metals - such as Cd - from polluted soils. PIXE and STIM analyses were applied to investigate Cd-uptake in roots and the resulting effects on the elemental distribution of Cd stressed plants. The axial distribution of trace elements as a function of distance from the root tip as well as the radial distribution within cross-sections were analysed. The results are compared with the elemental distribution in control plants.

Accumulation of Heavy Metals (Pb, Cd, V) in Sediment, roots and ...

African Journals Online (AJOL)

Michael Horsfall

info and www.bioline.org.br/ja. Accumulation of Heavy Metals (Pb, Cd, V) in Sediment, roots and leaves of ... ABSTRACT: Sirik mangrove forests harbour two species, Avicennia marina and .... Based on the soil critical concentration value of Pb.

Activation of AMPK by berberine induces hepatic lipid accumulation by upregulation of fatty acid translocase CD36 in mice

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Choi, You-Jin; Lee, Kang-Yo; Jung, Seung-Hwan; Kim, Hyung Sik; Shim, Gayong; Kim, Mi-Gyeong; Oh, Yu-Kyoung; Oh, Seon-Hee; Jun, Dae Won; Lee, Byung-Hoon

2017-01-01

Emerging evidence has shown that berberine has a protective effect against metabolic syndrome such as obesity and type II diabetes mellitus by activating AMP-activated protein kinase (AMPK). AMPK induces CD36 trafficking to the sarcolemma for fatty acid uptake and oxidation in contracting muscle. However, little is known about the effects of AMPK on CD36 regulation in the liver. We investigated whether AMPK activation by berberine affects CD36 expression and fatty acid uptake in hepatocytes and whether it is linked to hepatic lipid accumulation. Activation of AMPK by berberine or transduction with adenoviral vectors encoding constitutively active AMPK in HepG2 and mouse primary hepatocytes increased the expression and membrane translocation of CD36, resulting in enhanced fatty acid uptake and lipid accumulation as determined by BODIPY-C16 and Nile red fluorescence, respectively. Activation of AMPK by berberine induced the phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2) and subsequently induced CCAAT/enhancer-binding protein β (C/EBPβ) binding to the C/EBP-response element in the CD36 promoter in hepatocytes. In addition, hepatic CD36 expression and triglyceride levels were increased in normal diet-fed mice treated with berberine, but completely prevented when hepatic CD36 was silenced with adenovirus containing CD36-specific shRNA. Taken together, prolonged activation of AMPK by berberine increased CD36 expression in hepatocytes, resulting in fatty acid uptake via processes linked to hepatocellular lipid accumulation and fatty liver. - Highlights: • Berberine increases the expression and membrane translocation of CD36 in hepatocytes. • The increase of CD36 results in enhanced fatty acid uptake and lipid accumulation. • Berberine-induced fatty liver is mediated by AMPK-ERK-C/EBPβ pathway. • CD36-specific shRNA inhibited berberine-induced lipid accumulation in liver.

Activation of AMPK by berberine induces hepatic lipid accumulation by upregulation of fatty acid translocase CD36 in mice

Energy Technology Data Exchange (ETDEWEB)

Choi, You-Jin; Lee, Kang-Yo; Jung, Seung-Hwan [College of Pharmacy, Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, Hyung Sik [School of Pharmacy, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Shim, Gayong; Kim, Mi-Gyeong; Oh, Yu-Kyoung [College of Pharmacy, Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 151-742 (Korea, Republic of); Oh, Seon-Hee [The Division of Natural Medical Sciences, College of Health Science, Chosun University, Gwangju 501-759 (Korea, Republic of); Jun, Dae Won [Internal Medicine, Hanyang University School of Medicine, Seoul 133-791 (Korea, Republic of); Lee, Byung-Hoon, E-mail: lee@snu.ac.kr [College of Pharmacy, Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 151-742 (Korea, Republic of)

2017-02-01

Emerging evidence has shown that berberine has a protective effect against metabolic syndrome such as obesity and type II diabetes mellitus by activating AMP-activated protein kinase (AMPK). AMPK induces CD36 trafficking to the sarcolemma for fatty acid uptake and oxidation in contracting muscle. However, little is known about the effects of AMPK on CD36 regulation in the liver. We investigated whether AMPK activation by berberine affects CD36 expression and fatty acid uptake in hepatocytes and whether it is linked to hepatic lipid accumulation. Activation of AMPK by berberine or transduction with adenoviral vectors encoding constitutively active AMPK in HepG2 and mouse primary hepatocytes increased the expression and membrane translocation of CD36, resulting in enhanced fatty acid uptake and lipid accumulation as determined by BODIPY-C16 and Nile red fluorescence, respectively. Activation of AMPK by berberine induced the phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2) and subsequently induced CCAAT/enhancer-binding protein β (C/EBPβ) binding to the C/EBP-response element in the CD36 promoter in hepatocytes. In addition, hepatic CD36 expression and triglyceride levels were increased in normal diet-fed mice treated with berberine, but completely prevented when hepatic CD36 was silenced with adenovirus containing CD36-specific shRNA. Taken together, prolonged activation of AMPK by berberine increased CD36 expression in hepatocytes, resulting in fatty acid uptake via processes linked to hepatocellular lipid accumulation and fatty liver. - Highlights: • Berberine increases the expression and membrane translocation of CD36 in hepatocytes. • The increase of CD36 results in enhanced fatty acid uptake and lipid accumulation. • Berberine-induced fatty liver is mediated by AMPK-ERK-C/EBPβ pathway. • CD36-specific shRNA inhibited berberine-induced lipid accumulation in liver.

Phytochelatin and cadmium accumulation in wheat.

NARCIS (Netherlands)

Stolt, J.P.; Sneller, F.E.C.; Bryngelson, T.; Lundborg, T.; Schat, H.

2003-01-01

Cadmium (Cd) is a nonessential heavy metal that can be harmful at low concentrations in organisms. Therefore, it is necessary to decrease Cd accumulation in the grains of wheats aimed for human consumption. In response to Cd, higher plants synthesize sulphur-rich peptides, phytochelatins (PCs).

Herpes simplex virus-1 evasion of CD8+ T cell accumulation contributes to viral encephalitis.

Science.gov (United States)

Koyanagi, Naoto; Imai, Takahiko; Shindo, Keiko; Sato, Ayuko; Fujii, Wataru; Ichinohe, Takeshi; Takemura, Naoki; Kakuta, Shigeru; Uematsu, Satoshi; Kiyono, Hiroshi; Maruzuru, Yuhei; Arii, Jun; Kato, Akihisa; Kawaguchi, Yasushi

2017-10-02

Herpes simplex virus-1 (HSV-1) is the most common cause of sporadic viral encephalitis, which can be lethal or result in severe neurological defects even with antiviral therapy. While HSV-1 causes encephalitis in spite of HSV-1-specific humoral and cellular immunity, the mechanism by which HSV-1 evades the immune system in the central nervous system (CNS) remains unknown. Here we describe a strategy by which HSV-1 avoids immune targeting in the CNS. The HSV-1 UL13 kinase promotes evasion of HSV-1-specific CD8+ T cell accumulation in infection sites by downregulating expression of the CD8+ T cell attractant chemokine CXCL9 in the CNS of infected mice, leading to increased HSV-1 mortality due to encephalitis. Direct injection of CXCL9 into the CNS infection site enhanced HSV-1-specific CD8+ T cell accumulation, leading to marked improvements in the survival of infected mice. This previously uncharacterized strategy for HSV-1 evasion of CD8+ T cell accumulation in the CNS has important implications for understanding the pathogenesis and clinical treatment of HSV-1 encephalitis.

Cadmium accumulation in the rootless macrophyte Wolffia globosa and its potential for phytoremediation.

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Xie, Wan-Ying; Huang, Qing; Li, Gang; Rensing, Christopher; Zhu, Yong-Guan

2013-01-01

Cadmium (Cd) pollution around the world is a serious issue demanding acceptable solutions, one of which is phytoremediation that is both cost-effective and eco-friendly. Removal of Cd from contaminated water using plants with high growth rates and sufficient Cd accumulation abilities could be an appropriate choice. Here, we investigated a potential Cd accumulator, Wolffia, a rootless duckweed with high growth rate. Cd uptake, accumulation, tolerance, and phytofiltration ability by Wolffia globosa were examined. Furthermore, the effects of arsenic (As) on Cd uptake and phytofiltration by W. globosa were also studied. Cd uptake kinetics showed a linear pattern and a hyperbolic pattern without a plateau in lower (0-2 microM) and higher (0-200 microM) Cd concentration ranges, respectively, suggesting rapid Cd uptake by W. globosa Cd accumulation ability by W. globosa was higher at Cd concentrations 10 microM. All the five species of Wolffia exposed to I microM Cd for 5 days accumulated > 500 mg Cd kg(-1) DW. Ten gram fresh W. globosa could diminish almost all the Cd (2 microM) in a 200 mL solution. This enormous accumulation ability was mostly due to passive adsorption of Cd by the apoplast. Arsenic had no significant effect on Cd uptake and phytofiltration. The fresh fronds also showed a great As extracting ability. The results indicated that Wolffia is a strong Cd accumulator and has great Cd phytoremediation potential. Therefore, this plant can be used in fresh aquatic environments co-contaminated by low-levels of Cd and As.

Cadmium accumulation in sunflower plants influenced by arbuscular mycorrhiza.

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de Andrade, Sara Adrián López; da Silveira, Adriana Parada Dias; Jorge, Renato Atílio; de Abreu, Mônica Ferreira

2008-01-01

In order to investigate the cadmium (Cd) accumulation patterns and possible alleviation of Cd stress by mycorrhization, sunflower plants (Helianthus annuus L.) were grown in the presence or absence of Cd (20 micromol L(-1)) and inoculated or not inoculated with the arbuscular mycorrhizal fungus (AMF) Glomus intraradices. No visual symptoms of Cd phytotoxicity were observed; nevertheless, in non-mycorrhizal plants the presence of Cd decreased plant growth. The addition of Cd had no significant effect on either mycorrhizal colonization or the amount of extra-radical mycelia that was produced by the AMF. Cd accumulated mainly in roots; only 22% of the total Cd absorbed was translocated to the shoots, where it accumulated to an average of 228 mg Cd kg(-1). Although the shoot-to-root ratio of Cd was similar in both the AMF inoculated and non-inoculated plants, the total absorbed Cd was 23% higher in mycorrhizal plants. Cd concentration in AMF extra-radical mycelium was 728 microg g(-1) dry weight. Despite the greater absorption of Cd, mycorrhizal plants showed higher photosynthetic pigment concentrations and shoot P contents. Cd also influenced mineral nutrition, leading to decreased Ca and Cu shoot concentrations; N, Fe and Cu shoot contents; and increased S and K shoot concentrations. Cd induced guaiacol peroxidase activity in roots in both mycorrhizal and non-mycorrhizal plants, but this increase was much more accentuated in non-mycorrhizal roots. In conclusion, sunflower plants associated with G. intraradices were less sensitive to Cd stress than non-mycorrhizal plants. Mycorrhizal sunflowers showed enhanced Cd accumulation and some tolerance to excessive Cd concentrations in plant tissues.

Cadmium toxicity in Maize (Zea mays L.): consequences on antioxidative systems, reactive oxygen species and cadmium accumulation.

Science.gov (United States)

Anjum, Shakeel Ahmad; Tanveer, Mohsin; Hussain, Saddam; Bao, Mingchen; Wang, Longchang; Khan, Imran; Ullah, Ehsan; Tung, Shahbaz Atta; Samad, Rana Abdul; Shahzad, Babar

2015-11-01

Increased cadmium (Cd) accumulation in soils has led to tremendous environmental problems, with pronounced effects on agricultural productivity. Present study investigated the effects of Cd stress imposed at various concentrations (0, 75, 150, 225, 300, 375 μM) on antioxidant activities, reactive oxygen species (ROS), Cd accumulation, and productivity of two maize (Zea mays L.) cultivars viz., Run Nong 35 and Wan Dan 13. Considerable variations in Cd accumulation and in behavior of antioxidants and ROS were observed under Cd stress in both maize cultivars, and such variations governed by Cd were concentration dependent. Exposure of plant to Cd stress considerably increased Cd concentration in all plant parts particularly in roots. Wan Dan 13 accumulated relatively higher Cd in root, stem, and leaves than Run Nong 35; however, in seeds, Run Nong 35 recorded higher Cd accumulation. All the Cd toxicity levels starting from 75 μM enhanced H2O2 and MDA concentrations and triggered electrolyte leakage in leaves of both cultivars, and such an increment was more in Run Nong 35. The ROS were scavenged by the enhanced activities of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, and glutathione peroxidase in response to Cd stress, and these antioxidant activities were higher in Wan Dan 13 compared with Run Nong 35 at all Cd toxicity levels. The grain yield of maize was considerably reduced particularly for Run Nong 35 under different Cd toxicity levels as compared with control. The Wan Dan 13 was better able to alleviate Cd-induced oxidative damage which was attributed to more Cd accumulation in roots and higher antioxidant activities in this cultivar, suggesting that manipulation of these antioxidants and enhancing Cd accumulation in roots may lead to improvement in Cd stress tolerance.

Uptake and translocation of 109Cd and stable Cd within tobacco plants (Nicotiana sylvestris)

International Nuclear Information System (INIS)

Rosén, K.; Eriksson, J.; Vinichuk, M.

2012-01-01

The availability, uptake, and translocation of recently added ( 109 Cd) and naturally occurring (stable) soil Cd within tobacco plants were compared. 109 Cd was added to soil in two treatments, A (0.25 MBq kg soil −1 DW) and B (eight-fold dose): stable Cd was measured in both treatments. Both the added and the stable Cd were higher in leaves and reproductive structures of the plant than in stalks and roots. The uptake of 109 Cd was 5.3 kBq plant −1 for treatment A and 36.7 kBq plant −1 for treatment B, and about 26 μg plant −1 for stable Cd. Leaves of the tobacco plants accumulated 40–45% of the total 109 Cd and about 50% of total stable Cd taken up by the plant. Cadmium concentration in the plant was three times higher than in roots and two times higher than the concentration in soil: the concentration in roots was lower than in the soil. - Capsule: The availability, uptake, and translocation of recently added ( 109 Cd) and naturally occurring (stable) soil Cd within tobacco plants (Nicotiana sylvestris) were investigated. - Highlights: ► We compared uptake recently added and naturally occurring soil Cd by tobacco plant. ► Both added and stable Cd display similar uptake and translocation within the plant. ► Leaves of tobacco plants accumulate half of the total Cd taken up by the plant. ► Recently added 109 Cd to soil is more available than naturally occurring cadmium.

A patient with type I CD36 deficiency whose myocardium accumulated 123I-BMIPP after 4 years.

Science.gov (United States)

Ito, K; Sugihara, H; Tanabe, T; Zen, K; Hikosaka, T; Adachi, Y; Katoh, S; Azuma, A; Nakagawa, M

2001-06-01

A 73-year-old man with aortic regurgitation was examined by 123I-alpha-methyl-p-iodophenylpentadecanoic acid (BMIPP) myocardial single photon emission computed tomography (SPECT) in 1995. Myocardial accumulation was not evident on either the early or the delayed image obtained 15 minutes and 3 hours, respectively, after injecting 123I-BMIPP. Flow cytometric analysis of CD36 expression in monocytes and platelets identified a type I CD36 deficiency. The patient was hospitalized for severe heart failure in 1999. Upon admission, the cardiothoracic ratio on chest X-rays was 73%, and the left ventricular end-diastolic diameter on echocardiograms was enlarged to 77 mm. On the second day, we performed 123I-BMIPP myocardial SPECT. Myocardial accumulation was evident in the delayed, but not in the early image. We repeated 123I-BMIPP myocardial SPECT on the 10th day after admission. Myocardial accumulation was evident on both early and delayed images. 99mTc-tetrofosmin myocardial SPECT was immediately performed after 123I-BMIPP myocardial SPECT to distinguish myocardial from pooling images in the left ventricle, but, because the images from both 99Tc-tetrofosmin and 123I-BMIPP myocardial SPECT were idential, we considered that the 123I-BMIPP myocardial SPECT images reflected the actual myocardial condition. The CD36 molecule transports long-chain fatty acid (LCFA) on the myocardial membrane, but 123I-BMIPP scintigraphy does not show any myocardial accumulation in patients with type I CD36 deficiency, indicating that myocardial LCFA uptake occurs through CD36 on the human myocardial membrane. Even though our patient had type I CD36 deficiency, BMIPP was uptaken by the myocardium during heart failure, suggesting a variant pathway on the human myocardial membrane for LCFA uptake.

Mechanisms of Fe biofortification and mitigation of Cd accumulation in rice (Oryza sativa L.) grown hydroponically with Fe chelate fertilization.

Science.gov (United States)

Chen, Zhe; Tang, Ye-Tao; Zhou, Can; Xie, Shu-Ting; Xiao, Shi; Baker, Alan J M; Qiu, Rong-Liang

2017-05-01

Cadmium contaminated rice from China has become a global food safety issue. Some research has suggested that chelate addition to substrates can affect metal speciation and plant metal content. We investigated the mitigation of Cd accumulation in hydroponically-grown rice supplied with EDTANa 2 Fe(II) or EDDHAFe(III). A japonica rice variety (Nipponbare) was grown in modified Kimura B solution containing three concentrations (0, 10, 100 μΜ) of the iron chelates EDTANa 2 Fe(II) or EDDHAFe(III) and 1 μΜ Cd. Metal speciation in solution was simulated by Geochem-EZ; growth and photosynthetic efficiency of rice were evaluated, and accumulation of Cd and Fe in plant parts was determined. Net Cd fluxes in the meristematic zone, growth zone, and maturation zone of roots were monitored by a non-invasive micro-test technology. Expression of Fe- and Cd-related genes in Fe-sufficient or Fe-deficient roots and leaves were studied by QRT-PCR. Compared to Fe deficiency, a sufficient or excess supply of Fe chelates significantly enhanced rice growth by elevating photosynthetic efficiency. Both Fe chelates increased the Fe content and decreased the Cd content of rice organs, except for the Cd content of roots treated with excess EDDHAFe(III). Compared to EDDHAFe(III), EDTANa 2 Fe(II) exhibited better mitigation of Cd accumulation in rice by generating the EDTANa 2 Cd complex in solution, decreasing net Cd influx and increasing net Cd efflux in root micro-zones. Application of EDTANa 2 Fe(II) and EDDHAFe(III) also reduced Cd accumulation in rice by inhibiting expression of genes involved in transport of Fe and Cd in the xylem and phloem. The 'win-win' situation of Fe biofortification and Cd mitigation in rice was achieved by application of Fe chelates. Root-to-stem xylem transport of Cd and redistribution of Cd in leaves by phloem transport can be regulated in rice through the use of Fe chelates that influence Fe availability and Fe-related gene expression. Fe fertilization

Differences in grain ultrastructure, phytochemical and proteomic profiles between the two contrasting grain Cd-accumulation barley genotypes.

Directory of Open Access Journals (Sweden)

Hongyan Sun

Full Text Available To reveal grain physio-chemical and proteomic differences between two barley genotypes, Zhenong8 and W6nk2 of high- and low-grain-Cd-accumulation, grain profiles of ultrastructure, amino acid and proteins were compared. Results showed that W6nk2 possesses significantly lower protein content, with hordein depicting the greatest genotypic difference, compared with Zhenong8, and lower amino acid contents with especially lower proportion of Glu, Tyr, Phe and Pro. Both scanning and transmission electron microscopy observation declared that the size of A-type starch molecule in W6nk2 was considerably larger than that of Zhenong8. Grains of Zhenong8 exhibited more protein-rich deposits around starch granules, with some A-type granules having surface pits. Seventeen proteins were identified in grains, using 2-DE coupled with mass spectrometry, with higher expression in Zhenong8 than that in W6nk2; including z-type serpin, serpin-Z7 and alpha-amylase/trypsin inhibitor CM, carbohydrate metabolism, protein synthesis and signal transduction related proteins. Twelve proteins were less expressed in Zhenong8 than that in W6nk2; including barley trypsin inhibitor chloroform/methanol-soluble protein (BTI-CMe2.1, BTI-CMe2.2, trypsin inhibitor, dehydroascorbate reductase (DHAR, pericentrin, dynein heavy chain and some antiviral related proteins. The data extend our understanding of mechanisms underlying Cd accumulation/tolerance and provides possible utilization of elite genetic resources in developing low-grain-Cd barley cultivars.

Water management practices affect arsenic and cadmium accumulation in rice grains.

Science.gov (United States)

Sun, Liming; Zheng, Manman; Liu, Hongyan; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Nie, Lixiao

2014-01-01

Cadmium (Cd) and arsenic (As) accumulation in rice grains is a great threat to its productivity, grain quality, and thus human health. Pot and field studies were carried out to unravel the effect of different water management practices (aerobic, aerobic-flooded, and flooded) on Cd and As accumulation in rice grains of two different varieties. In pot experiment, Cd or As was also added into the soil as treatment. Pots without Cd or As addition were maintained as control. Results indicated that water management practices significantly influenced the Cd and As concentration in rice grains and aerobic cultivation of rice furnished less As concentration in its grains. Nonetheless, Cd concentration in this treatment was higher than the grains of flooded rice. Likewise, in field study, aerobic and flooded rice cultivation recorded higher Cd and As concentration, respectively. However, growing of rice in aerobic-flooded conditions decreased the Cd concentration by 9.38 times on average basis as compared to aerobic rice. Furthermore, this treatment showed 28% less As concentration than that recorded in flooded rice cultivation. The results suggested that aerobic-flooded cultivation may be a promising strategy to reduce the Cd and As accumulations in rice grains simultaneously.

Immunosenescent CD57+CD4+ T-cells Accumulate and Contribute to Interferon-γ Responses in HIV Patients Responding Stably to ART

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Sonia Fernandez

2011-01-01

Full Text Available HIV-infected individuals responding to antiretroviral therapy (ART after severe CD4+ T-cell depletion may retain low responses to recall antigens [eg: cytomegalovirus (CMV] and altered expression of T-cell co-stimulatory molecules consistent with immunosenescence. We investigated the capacity of phenotypically senescent cells to generate cytokines in HIV patients receiving long-term ART (n = 18 and in healthy controls (n = 10. Memory T-cells were assessed by interferon (IFN-γ ELISpot assay and flow cytometrically via IFN-γ or IL-2. Proportions of CD57brightCD28null CD4+ T-cells correlated with IFN-γ responses to CMV (p = 0.009 and anti-CD3 (p = 0.002 in HIV patients only. Proportions of CD57brightCD28null CD8+ T-cells and CD8+ T-cell IFN-γ responses to CMV peptides correlated in controls but not HIV patients. IL-2 was predominantly produced by CD28+T-cells from all donors, whereas IFN-γ was mostly produced by CD57+ T-cells. The findings provide evidence of an accumulation of immunosenescent T-cells able to make IFN-γ. This may influence the pathogenesis of secondary viral infections in HIV patients receiving ART.

Genotypic variations in the accumulation of Cd, Cu, Pb and Zn exhibited by six commonly grown vegetables

International Nuclear Information System (INIS)

Alexander, P.D.; Alloway, B.J.; Dourado, A.M.

2006-01-01

Metal contaminants in garden and allotment soils could possibly affect human health through a variety of pathways. This study focused on the potential pathway of consumption of vegetables grown on contaminated soil. Five cultivars each of six common vegetables were grown in a control and in a soil spiked with Cd, Cu, Pb and Zn. Highly significant differences in metal content were evident between cultivars of a number of vegetables for several of the contaminants. Carrot and pea cultivars exhibited significant differences in accumulated concentrations of Cd and Cu with carrot cultivars also exhibiting significant differences in Zn. Distinctive differences were also identified when comparing one vegetable to another, legumes (Leguminosae) tending to be low accumulators, root vegetables (Umbelliferae and Liliaceae) tending to be moderate accumulators and leafy vegetables (Compositae and Chenopodiaceae) being high accumulators. - Genotypic differences between cultivars of vegetable species can be important in determining the extent of accumulation of metals from contaminated soil

Cadmium Accumulation and Its Toxicity in Brittle Culm 1 (bc1, a Fragile Rice Mutant

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Guo-sheng SHAO

2007-09-01

Full Text Available Cadmium (Cd accumulation and toxicity in rice plants were characterized and identified by using brittle culm 1 (bc1, a fragile rice mutant and its wild type (Shuangkezao, an indica rice as materials by hydroponics. The low Cd level didn't obviously affect the growth parameters in both rice genotypes, but under high Cd levels (1.0 and 5.0 μmol/L, the growth of both rice plants were substantially inhibited. Moreover, bc1 tended to suffer more seriously from Cd toxicity than Shuangkezao. Cd accumulation in both rice plants increased with the increase of Cd levels. There was a significant difference in Cd accumulation between the two rice genotypes with constantly higher Cd concentration in bc1, which also accumulated more Cd at 0, 0.1, and 1.0 μmol/L Cd levels. The same case was found in the two rice plants grown on Cd-contaminated soil. This suggested that cell wall might play an important role in Cd accumulation in rice plants by the physiological mechanisms. The malondialdehyde (MDA content, superoxide dismutase (SOD and peroxidase (POD activities in rice plants were affected differently under Cd treatments, and which implied that POD might play the main role in detoxifying active oxygen free radical. A significant difference in antioxidative system between the two rice genotypes was found with constantly higher MDA content, SOD and POD activities in bc1. In summary, bc1 accumulated more Cd and appeared to be more sensitive to Cd stress compared with its wild type.

Foliar application with nano-silicon alleviates Cd toxicity in rice seedlings.

Science.gov (United States)

Wang, Shihua; Wang, Fayuan; Gao, Shuangcheng

2015-02-01

Nanofertilizers may be more effective than regular fertilizers in improving plant nutrition, enhancing nutrition use efficiency, and protecting plants from environmental stress. A hydroponic pot experiment was conducted to study the role of foliar application with 2.5 mM nano-silicon in alleviating Cd stress in rice seedlings (Oryza sativa L. cv Youyou 128) grown in solution added with or without 20 μM CdCl2. The results showed that Cd treatment decreased the growth and the contents of Mg, Fe, Zn, chlorophyll a, and glutathione (GSH), accompanied by a significant increase in Cd accumulation. However, foliar application with nano-Si improved the growth, Mg, Fe, and Zn nutrition, and the contents of chlorophyll a of the rice seedlings under Cd stress and decreased Cd accumulation and translocation of Cd from root to shoot. Cd treatment produced oxidative stress to rice seedlings indicated by a higher lipid peroxidation level (as malondialdehyde (MDA)) and higher activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and a lower GSH content. However, those nano-Si-treated plants had lower MDA but higher GSH content and different antioxidant enzyme activities, indicating a higher Cd tolerance in them. The results suggested that nano-Si application alleviated Cd toxicity in rice by decreasing Cd accumulation, Cd partitioning in shoot and MDA level and by increasing content of some mineral elements (Mg, Fe, and Zn) and antioxidant capacity.

Gomphrena claussenii, the first South American metallophyte species with indicator-like Zn and Cd accumulation and extreme metal tolerance

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Mina eT. Villafort Carvalho

2013-06-01

Full Text Available Plant species with the capacity to tolerate heavy metals are potentially useful for phytoremediation since they have adapted to survive and reproduce under toxic conditions and to accumulate high metal concentrations. Gomphrena claussenii Moq., a South-American species belonging to the Amaranthaceae, is found at a zinc (Zn mining area in the state of Minas Gerais, Brazil. Through soil and hydroponic experiments, the metal tolerance and accumulation capacities of G. claussenii were assessed and the effects on physiological characteristics were compared with a closely-related non-tolerant species, Gomphrena elegans Mart. Gomphrena. claussenii plants grown in soil sampled at the Zn smelting area accumulated up to 5318 µg g-1 of Zn and 287 µg g-1 of Cd in shoot dry biomass after 30 days of exposure. Plants were grown in hydroponics containing up to 3000 µM of Zn and 100 µM of Cd for G. claussenii and 100 µM of Zn and 5 µM of Cd for G. elegans. Gomphrena claussenii proved to be an extremely tolerant species to both Zn and Cd, showing only slight metal toxicity symptoms at the highest treatment levels, without significant decrease in biomass and no effects on root growth, whereas the non-tolerant species G. elegans showed significant toxicity effects at the highest exposure levels. Both species accumulated more Zn and Cd in roots than in shoots. In G. elegans over 90% of the Cd remained in the roots, but G. claussenii showed a root:shoot concentration ratio of around 2, with shoots reaching 0.93 % Zn and 0.13 % Cd on dry matter base. In G. claussenii shoots, the concentrations of other minerals, such as Fe and Mn, were only affected by the highest Zn treatment while in G. elegans the Fe and Mn concentrations in shoots decreased drastically at both Zn and Cd treatments. Taking together, these results indicate that G. claussenii is a novel metallophyte, extremely tolerant of high Zn and Cd exposure and an interesting species for further

Differential effects of citric acid on cadmium uptake and accumulation between tall fescue and Kentucky bluegrass.

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Wang, ShuTing; Dong, Qin; Wang, ZhaoLong

2017-11-01

Organic acids play an important role in cadmium availability, uptake, translocation, and detoxification. A sand culture experiment was designed to investigate the effects of citric acid on Cd uptake, translocation, and accumulation in tall fescue and Kentucky bluegrass. The results showed that two grass species presented different Cd chemical forms, organic acid components and amount in roots. The dormant Cd accumulated in roots of tall fescue was the pectate- and protein- integrated form, which contributed by 84.85%. However, in Kentucky bluegrass, the pectate- and protein- integrated Cd was only contributed by 35.78%, and the higher proportion of Cd form was the water soluble Cd-organic acid complexes. In tall fescue, citric acid dramatically enhanced 2.8 fold of Cd uptake, 3 fold of root Cd accumulation, and 2.3 fold of shoot Cd accumulation. In Kentucky bluegrass, citric acid promoted Cd accumulation in roots, but significantly decreased Cd accumulation in shoots. These results suggested that the enhancements of citric acid on Cd uptake, translocation, and accumulation in tall fescue was associated with its promotion of organic acids and the water soluble Cd-organic acid complexes in roots. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of waterborne Cu and Cd on anti-oxidative response, lipid peroxidation and heavy metals accumulation in abalone Haliotis discus hannai ino

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Lei, Yanju; Zhang, Wenbing; Xu, Wei; Zhang, Yanjiao; Zhou, Huihui; Mai, Kangsen

2015-06-01

The aim of this study was to compare the effects of waterborne copper (Cu) and cadmium (Cd) on survival, anti-oxidative response, lipid peroxidation and metal accumulation in abalone Haliotis discus hannai. Experimental animals (initial weight: 7.49 g ± 0.01 g) were exposed to graded concentrations of waterborne Cu (0.02, 0.04, 0.06, 0.08 mg L-1) or Cd (0.025, 0.05, 0.25, 0.5 mg L-1) for 28 days, respectively. Activities of the anti-oxidative enzymes (catalase, CAT; superoxide dismutase, SOD; glutathione peroxidases, GPx; glutathione S-transferase, GST), contents of the reduced glutathione (GSH) and malondiadehyde (MDA) in the hepatopancreas, and metal accumulation in hepatopancreas and muscles were analyzed after 0, 1, 3, 6, 10, 15, 21, 28 days of metal exposure, respectively. Results showed that 0.04 mg L-1, 0.06 mg L--1 and 0.08 mg L-1 Cu caused 100% death of abalone on the 21st, 10th and 6th day, respectively. However, no dead abalone was found during the 28-day waterborne Cd exposure at all experimental concentrations. Generally, activities of SOD and GST in hepatopancreas under all Cu concentrations followed a decrease trend as the exposure time prolonged. However, these activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Activities of CAT in all Cu exposure treatments were higher than those in the control. These activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Contents of MDA in hepatopancreas in all Cu treatments significantly increased first and then decreased to the control level. However, the MDA contents in hepatopancreas were not significantly changed during the 28-day Cd exposure. The metals accumulation in both hepatopancreas and muscles of abalone significantly increased with the increase of waterborne metals concentration and exposure time. These results indicated that H. discus hannai has a positive anti-oxidative defense

Metals Accumulation and Leaf Surface Anatomy of Murdannia spectabilis Growing in Zn/Cd Contaminated Soil

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Ladawan Rattanapolsan

2013-07-01

Full Text Available Murdannia spectabilis (Kurz Faden was identified as a Zn/Cd hyperaccumulative plant. Leaf surface anatomy of the plant growing in non-contaminated soil (control and Zn/Cd contaminated soil,was studied and compared by a light microscopy and scanning electron microscopy combined with Energy-dispersive X-ray spectroscopy(SEM/EDS. The similarities were reticulate cuticle on epidermises, uniform polygonal cell, stomatal arrangement in six surrounding subsidiary cells, and submarginal sclerenchyma. The dissimilarities were uniserate trichomes spreading on both adaxial and abaxial epidermis of the plants growing in non-contaminated soil, whereas the uniserate trichomes were only on the submarginal-adaxial epidermis of the control plants. The trichomes on leaves of the plants growing in non-contaminated soil were found to have both uniseriate non-glandular and uniseriate glandular trichomes;whereas, leaves of the plants growing in the contaminated soil were merely non-glandular trichomes. The different shape and location of trichomes, the number of stomata and trichome indicated the effect of Zn and Cd on M. spectabilis. The higher percentages of Zn and Cd in the vascular bundle than in the cross section and epidermis areas showed both solutes could move along each route, with diffusion through the symplast and apoplast. The increase of Ca in M. spectabilis growing in Zn/Cd contaminated soil corresponded to the Zn and Cd distributed in the leaves. Zn K-edge and S K-edge XANES spectra proposed that Zn2+ ions were accumulated and/or adsorbed on the epidermis of the tuber, and then absorbed into the root and transport to the xylem. The double peaks of Zn-cysteine in the leaf samples proposed the metal sequestration was by sulphur proteins.

Ocean acidification increases cadmium accumulation in marine bivalves: a potential threat to seafood safety.

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Shi, Wei; Zhao, Xinguo; Han, Yu; Che, Zhumei; Chai, Xueliang; Liu, Guangxu

2016-01-21

To date, the effects of ocean acidification on toxic metals accumulation and the underlying molecular mechanism remains unknown in marine bivalve species. In the present study, the effects of the realistic future ocean pCO2 levels on the cadmium (Cd) accumulation in the gills, mantle and adductor muscles of three bivalve species, Mytilus edulis, Tegillarca granosa, and Meretrix meretrix, were investigated. The results obtained suggested that all species tested accumulated significantly higher Cd (p ocean acidification-induced increase in Cd accumulation may have occurred due to (i) the ocean acidification increased the concentration of Cd and the Cd(2+)/Ca(2+) in the seawater, which in turn increased the Cd influx through Ca channel; (ii) the acidified seawater may have brought about epithelia damage, resulting in easier Cd penetration; and (iii) ocean acidification hampered Cd exclusion.

Soil geochemical factors regulate Cd accumulation by metal hyperaccumulating Noccaea caerulescens (J. Presl & C. Presl) F.K. Mey in field-contaminated soils.

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Rosenfeld, Carla E; Chaney, Rufus L; Martínez, Carmen E

2018-03-01

Cadmium contamination in soil is a substantial global problem, and of significant concern due to high food-chain transfer. Cadmium hyperaccumulators are of particular interest because of their ability to tolerate and take up significant amounts of heavy metal pollution from soils. One particular plant, Noccaea caerulescens (formerly, Thlaspi caerulescens), has been extensively studied in terms of its capacity to accumulate heavy metals (specifically Zn and Cd), though these studies have primarily utilized hydroponic and metal-spiked model soil systems. We studied Cd and nutrient uptake by two N. caerulescens ecotypes, Prayon (Zn-only hyperaccumulator) and Ganges (Zn- and Cd-hyperaccumulator) in four long-term field-contaminated soils. Our data suggest that individual soil properties such as total soil Cd, Zn:Cd molar ratio, or soil pH do not accurately predict Cd uptake by hyperaccumulating plants. Additionally, total Cd uptake by the hyperaccumulating Ganges ecotype was substantially less than its physiological capacity, which is likely due to Cd-containing solid phases (primarily iron oxides) and pH that play an important role in regulating and limiting Cd solubility. Increased P accumulation in the Ganges leaves, and greater plant Fe accumulation from Cd-containing soils suggests that rhizosphere alterations via proton, and potentially organic acid, secretion may also play a role in nutrient and Cd acquisition by the plant roots. The current study highlights the role that soil geochemical factors play in influencing Cd uptake by hyperaccumulating plants. While these plants may have high physiological potential to accumulate metals from contaminated soils, individual soil geochemical factors and the plant-soil interactions in that soil will dictate the actual amount of phytoextractable metal. This underlines the need for site-specific understanding of metal-containing solid phases and geochemical properties of soils before undertaking phytoextraction efforts

Cadmium tolerance and accumulation characteristics of Bidens pilosa L. as a potential Cd-hyperaccumulator

International Nuclear Information System (INIS)

Sun Yuebing; Zhou Qixing; Wang Lin; Liu Weitao

2009-01-01

Recently, researchers are becoming interested in using hyperaccumulators for decontamination of heavy metal polluted soils, whereas few species that hyperaccumulate cadmium (Cd) has been identified in the plant kingdom. In this study, the physiological mechanisms at the seedling stage and growth responses and Cd uptake and accumulation at flowering and mature stages of Bidens pilosa L. under Cd treatments were investigated. At the seedling stage, when soil Cd was lower than 16 mg kg -1 , the plant did not show obvious symptom of phytoxicity, and the alterations of chlorophyll (CHL), superoxide dismutase (SOD), peroxidase (POD), malondialdehyde (MDA), and soluble protein (SP) did not have significant differences when compared with the control. At the flowering and mature stages, under low Cd treatments (≤16 mg kg -1 ), the application of Cd could facilitate plant growth, resulting in 3.9-11.0% and 5.9-13.8%, respectively, increase in shoots dry biomass compared with the control. The Cd concentrations in stems, leaves and shoots exceeded 100 mg kg -1 when soil Cd was at 8 mg kg -1 , and they were positively correlated with Cd concentration in soils, the bioaccumulation factor (BF) and translocation factor (TF) values were all greater than 1.0. Thus, it is clear that B. pilosa has the basic characteristics of a Cd-hyperaccumulator. All the results elementarily indicated that B. pilosa is a potential Cd-hyperaccumulating plant

Remediation and Safe Production of cd Contaminated Soil Via Multiple Cropping Hyperaccumulator Solanum nigrum L. and Low Accumulation Chinese Cabbage.

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Niu, Mingfen; Wei, Shuhe; Bai, Jiayi; Wang, Siqi; Ji, Dandan

2015-01-01

Multiple crop experiment of hyperaccumulator Solanum nigrum L. with low accumulation Chinese cabbage Fenyuanxin 3 were conducted in a cadmium (Cd) contaminated vegetable field. In the first round, the average removal rate of S. nigrum to Cd was about 10% without assisted phytoextraction reagent addition for the top soil (0-20 cm) with Cd concentration at 0.53-0.97 mg kg(-1) after its grew 90 days. As for assisted phytoextraction reagent added plots, efficiency of Cd remediation might reach at 20%. However, in the second round, Cd concentration in Chinese cabbage was edible, even in the plots with assisted phytoextraction reagent added. Thus, multiple cropping hyperaccumulator with low accumulation crop could normally remediate contaminated soil and produce crop (obtain economic benefit) in one year, which may be one practical pathway of phytoremediating heavy metal contaminated soil in the future.

Thorax irradiation triggers a local and systemic accumulation of immunosuppressive CD4+ FoxP3+ regulatory T cells

International Nuclear Information System (INIS)

Wirsdörfer, Florian; Cappuccini, Federica; Niazman, Muska; Leve, Simone de; Westendorf, Astrid M; Lüdemann, Lutz; Stuschke, Martin; Jendrossek, Verena

2014-01-01

Lymphocyte infiltration is a common feature of radiation-induced pneumonitis and fibrosis, but their contribution to the pathogenic processes is still unclear. Here, we addressed the impact of thorax irradiation on the T cell compartment with a focus on immunosuppressive regulatory T cells (Treg). C57BL/6 wild type mice (WT) received anesthesia only (sham controls, 0 Gy) or were exposed to a single dose of whole thorax irradiation (15 Gy). Immune cells from lung tissue, spleen, and cervical lymph nodes were collected 10 to 84 days post-irradiation and phenotypically characterized by flow cytometry. Whole thorax irradiation provoked an increased influx of CD3+ T cells at 42 and 84 days post-irradiation. In contrast, local irradiation caused a sustained reduction in CD3+ T cells in peripheral lymphoid tissues. Interestingly, we observed a significant local and systemic increase in the fraction of CD4+ T cells expressing the transcription factor forkhead box P3 (FoxP3), the phenotypic marker for murine Treg, at day 21 post-irradiation. The accumulation of Treg was associated with increased levels of T cells expressing surface proteins characteristic for recruitment and immunosuppressive activity, e.g. CD103, CTLA-4 and CD73. Importantly, Treg isolated at this time point were able to suppress CD4+ effector T cells to a similar extent as Treg isolated from control mice. The response of the adaptive immune system to whole thorax irradiation is characterized by local immunoactivation and systemic immunosuppression. The transient accumulation of immunosuppressive CD4+ FoxP3+ Treg may be required to protect the lung against excessive inflammation-induced tissue damage. Further investigations shall define the mechanisms underlying the accumulation of Treg and their role for the pathogenesis of radiation-induced lung disease

Species- and age-related variation in metal exposure and accumulation of two passerine bird species

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Berglund, A.M.M., E-mail: asa.berglund@emg.umu.se [Section of Ecology, 20014 University of Turku (Finland); Koivula, M.J.; Eeva, T. [Section of Ecology, 20014 University of Turku (Finland)

2011-10-15

We measured the concentration of several elements (arsenic [As], calcium [Ca], cadmium [Cd], copper [Cu], nickel [Ni], lead [Pb], selenium [Se] and zinc [Zn]) in adult and nestling pied flycatchers (Ficedula hypoleuca) and great tits (Parus major) at different distances to a Cu-Ni smelter in 2009. Feces of nestlings generally failed to correspond with internal element concentrations but reflected the pollution exposure, indicating an increased stress by removal of excess metals. The uptake of Cu and Ni were regulated, but As, Cd, Pb and Se accumulated in liver tissue. Pied flycatchers had generally higher element concentrations than great tits. The higher accumulation of As and Pb in pied flycatcher livers was explained by a more efficient absorption, whereas the higher Cd concentration was primarily due to different intake of food items. Age-related differences occurred between the two species, though both Cd and Se accumulated with age. - Highlights: > We measured metal concentrations in feces and livers of two passerine species. > We examined species- and age-related differences in polluted environments. > Feces was evaluated as a useful non-destructive measure of increased stress. > Generally pied flycatchers accumulated higher concentrations than great tits. > Cadmium and selenium accumulated with age in both species. - Accumulation of metals in liver of two insectivorous passerines reflects inter-specific differences in diet, absorption rate and physiological requirements.

Species- and age-related variation in metal exposure and accumulation of two passerine bird species

International Nuclear Information System (INIS)

Berglund, A.M.M.; Koivula, M.J.; Eeva, T.

2011-01-01

We measured the concentration of several elements (arsenic [As], calcium [Ca], cadmium [Cd], copper [Cu], nickel [Ni], lead [Pb], selenium [Se] and zinc [Zn]) in adult and nestling pied flycatchers (Ficedula hypoleuca) and great tits (Parus major) at different distances to a Cu-Ni smelter in 2009. Feces of nestlings generally failed to correspond with internal element concentrations but reflected the pollution exposure, indicating an increased stress by removal of excess metals. The uptake of Cu and Ni were regulated, but As, Cd, Pb and Se accumulated in liver tissue. Pied flycatchers had generally higher element concentrations than great tits. The higher accumulation of As and Pb in pied flycatcher livers was explained by a more efficient absorption, whereas the higher Cd concentration was primarily due to different intake of food items. Age-related differences occurred between the two species, though both Cd and Se accumulated with age. - Highlights: → We measured metal concentrations in feces and livers of two passerine species. → We examined species- and age-related differences in polluted environments. → Feces was evaluated as a useful non-destructive measure of increased stress. → Generally pied flycatchers accumulated higher concentrations than great tits. → Cadmium and selenium accumulated with age in both species. - Accumulation of metals in liver of two insectivorous passerines reflects inter-specific differences in diet, absorption rate and physiological requirements.

Comparative accumulation of 109Cd and 75Se from water and food by an estuarine fish (Tetractenos glaber)

International Nuclear Information System (INIS)

Alquezar, Ralph; Markich, Scott J.; Twining, John R.

2008-01-01

Few data are available on the comparative accumulation of metal(loid)s from water and food in estuarine/marine fish. Smooth toadfish (Tetractenos glaber), commonly found in estuaries in south-eastern Australia, were separately exposed to radio-labelled seawater (14 kBq L -1 of 109 Cd and 24 kBq L -1 of 75 Se) and food (ghost shrimps; Trypaea australiensis: 875 Bq g -1109 Cd and 1130 Bq g -175 Se) for 25 days (uptake phase), followed by exposure to radionuclide-free water or food for 30 days (loss phase). Toadfish accumulated 109 Cd predominantly from water (85%) and 75 Se predominantly from food (62%), although the latter was lower than expected. For both the water and food exposures, 109 Cd was predominantly located in the gut lining (60-75%) at the end of the uptake phase, suggesting that the gut may be the primary pathway of 109 Cd uptake. This may be attributed to toadfish drinking large volumes of water to maintain osmoregulation. By the end of the loss phase, 109 Cd had predominantly shifted to the excretory organs - the liver (81%) in toadfish exposed to radio-labelled food, and in the liver, gills and kidney (82%) of toadfish exposed to radio-labelled water. In contrast, 75 Se was predominantly located in the excretory organs (gills, kidneys and liver; 66-76%) at the end of the uptake phase, irrespective of the exposure pathway, with minimal change in percentage distribution (76-83%) after the loss phase. This study emphasises the importance of differentiating accumulation pathways to better understand metal(loid) transfer dynamics and subsequent toxicity, in aquatic biota

Possible link between Hg and Cd accumulation in the brain of long-finned pilot whales (Globicephala melas)

Energy Technology Data Exchange (ETDEWEB)

Gajdosechova, Zuzana [Trace Element Speciation Laboratory, Department of Chemistry, Meston Walk, University of Aberdeen, Aberdeen AB24 3UE (United Kingdom); Brownlow, Andrew [SAC Wildlife Unit, Inverness (United Kingdom); Cottin, Nicolas T.; Fernandes, Mariana [Trace Element Speciation Laboratory, Department of Chemistry, Meston Walk, University of Aberdeen, Aberdeen AB24 3UE (United Kingdom); Read, Fiona L. [Oceanlab, University of Aberdeen, Main Street, Newburgh AB41 6AA (United Kingdom); Urgast, Dagmar S.; Raab, Andrea; Feldmann, Jörg; Krupp, Eva M. [Trace Element Speciation Laboratory, Department of Chemistry, Meston Walk, University of Aberdeen, Aberdeen AB24 3UE (United Kingdom)

2016-03-01

The bioaccumulation of metals was investigated by analysis of liver, kidney, muscle and brain tissue of a pod of 21 long-finned pilot whales (Globicephala melas) of all ages stranded in Scotland, UK. The results are the first to report cadmium (Cd) passage through the blood–brain barrier of pilot whales and provide a comprehensive study of the long-term (up to 35 years) mammalian exposure to the environmental pollutants. Additionally, linear accumulation of mercury (Hg) was observed in all studied tissues, whereas for Cd this was only observed in the liver. Total Hg concentration above the upper neurochemical threshold was found in the sub-adult and adult brains and methylmercury (MeHg) of 2.2 mg/kg was found in the brain of one individual. Inter-elemental analysis showed significant positive correlations of Hg with selenium (Se) and Cd with Se in all studied tissues. Furthermore, differences in the elemental concentrations in the liver and brain tissues were found between juvenile, sub-adult and adult groups. The highest concentrations of manganese, iron, zinc, Se, Hg and MeHg were noted in the livers, whereas Cd predominantly accumulated in the kidneys. High concentrations of Hg and Cd in the tissues of pilot whales presented in this study reflect ever increasing toxic stress on marine mammals. - Highlights: • Trace elements were measured in a pod of 21 pilot whales stranded in Scotland. • Bioaccumulation of mercury and methyl mercury was found in all studied tissues. • Cadmium age related accumulation was observed in the liver and brain tissues. • Cadmium-selenium correlations suggest formation of cadmium-selenium complexes.

Possible link between Hg and Cd accumulation in the brain of long-finned pilot whales (Globicephala melas)

International Nuclear Information System (INIS)

Gajdosechova, Zuzana; Brownlow, Andrew; Cottin, Nicolas T.; Fernandes, Mariana; Read, Fiona L.; Urgast, Dagmar S.; Raab, Andrea; Feldmann, Jörg; Krupp, Eva M.

2016-01-01

The bioaccumulation of metals was investigated by analysis of liver, kidney, muscle and brain tissue of a pod of 21 long-finned pilot whales (Globicephala melas) of all ages stranded in Scotland, UK. The results are the first to report cadmium (Cd) passage through the blood–brain barrier of pilot whales and provide a comprehensive study of the long-term (up to 35 years) mammalian exposure to the environmental pollutants. Additionally, linear accumulation of mercury (Hg) was observed in all studied tissues, whereas for Cd this was only observed in the liver. Total Hg concentration above the upper neurochemical threshold was found in the sub-adult and adult brains and methylmercury (MeHg) of 2.2 mg/kg was found in the brain of one individual. Inter-elemental analysis showed significant positive correlations of Hg with selenium (Se) and Cd with Se in all studied tissues. Furthermore, differences in the elemental concentrations in the liver and brain tissues were found between juvenile, sub-adult and adult groups. The highest concentrations of manganese, iron, zinc, Se, Hg and MeHg were noted in the livers, whereas Cd predominantly accumulated in the kidneys. High concentrations of Hg and Cd in the tissues of pilot whales presented in this study reflect ever increasing toxic stress on marine mammals. - Highlights: • Trace elements were measured in a pod of 21 pilot whales stranded in Scotland. • Bioaccumulation of mercury and methyl mercury was found in all studied tissues. • Cadmium age related accumulation was observed in the liver and brain tissues. • Cadmium-selenium correlations suggest formation of cadmium-selenium complexes.

Obesity-driven prepartal hepatic lipid accumulation in dairy cows is associated with increased CD36 and SREBP-1 expression.

Science.gov (United States)

Prodanović, Radiša; Korićanac, Goran; Vujanac, Ivan; Djordjević, Ana; Pantelić, Marija; Romić, Snježana; Stanimirović, Zoran; Kirovski, Danijela

2016-08-01

We investigated the hypothesis that obesity in dairy cows enhanced expression of proteins involved in hepatic fatty acid uptake and metabolism. Sixteen Holstein-Friesian close-up cows were divided into 2 equal groups based on their body condition score (BCS) as optimal (3.25≤BCS≤3.5) and high (4.0≤BCS≤4.25). Intravenous glucose tolerance test (GTT) and liver biopsies were carried out at day 10 before calving. Blood samples were collected before (basal) and after glucose infusion, and glucose, insulin and non-esterified fatty acid (NEFA) levels were determined at each sample point. In addition, β-hydroxybutyrate and triglycerides levels were measured in the basal samples. The liver biopsies were analyzed for total lipid content and protein expression of insulin receptor beta (IRβ), fatty acid translocase (FAT/CD36) and sterol regulatory element-binding protein-1 (SREBP-1). Basal glucose and insulin were higher in high-BCS cows, which coincided with higher circulating triglycerides and hepatic lipid content. Clearance rate and AUC for NEFA during GTT were higher in optimal-BCS cows. The development of insulin resistance and fatty liver in obese cows was paralleled by increased hepatic expression of the IRβ, CD36 and SREBP-1. These results suggest that increased expression of hepatic CD36 and SREBP-1 is relevant in the obesity-driven lipid accumulation in the liver of dairy cows during late gestation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Accumulation of Trace Metal Elements (Cu, Zn, Cd, and Pb in Surface Sediment via Decomposed Seagrass Leaves: A Mesocosm Experiment Using Zostera marina L.

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Shinya Hosokawa

Full Text Available Accumulation of Cu, Zn, Cd, and Pb in the sediment of seagrass ecosystems was examined using mesocosm experiments containing Zostera marina (eelgrass and reference pools. Lead was approximately 20-fold higher in the surface sediment in the eelgrass pool than in eelgrass leaves and epiphytes on the eelgrass leaves, whereas zinc and cadmium were significantly lower in the surface sediment than in the leaves, with intermediate concentrations in epiphytes. Copper concentrations were similar in both the surface sediment and leaves but significantly lower in epiphytes. Carbon and nitrogen contents increased significantly with increasing δ13C in surface sediments of both the eelgrass and reference pools. Copper, Zn, Cd, and Pb also increased significantly with increasing δ13C in the surface sediment in the eelgrass pool but not in the reference pool. By decomposition of eelgrass leaves with epiphytes, which was examined in the eelgrass pool, copper and lead concentrations increased more than 2-fold and approximately a 10-fold, whereas zinc and cadmium concentrations decreased. The high copper and lead concentrations in the surface sediment result from accumulation in decomposed, shed leaves, whereas zinc and cadmium remobilized from decomposed shed leaves but may remain at higher concentrations in the leaves than in the original sediments. The results of our mesocosm study demonstrate that whether the accumulation or remobilization of trace metals during the decomposition of seagrass leaves is trace metal dependent, and that the decomposed seagrass leaves can cause copper and lead accumulation in sediments in seagrass ecosystems.

Cadmium tolerance and accumulation in cultivars of a high-biomass tropical tree (Averrhoa carambola) and its potential for phytoextraction.

Science.gov (United States)

Li, J T; Liao, B; Lan, C Y; Ye, Z H; Baker, A J M; Shu, W S

2010-01-01

Averrhoa carambola is a high-biomass tropical tree that has been identified as a Cd accumulator. In the present study, field survey, pot, and hydroponic experiments were conducted to investigate the variation of Cd tolerance and accumulation in cultivars of A. carambola as well as its potential for phytoextraction. In the field survey, it was found that concentrations of Cd in aerial tissues of A. carambola varied greatly among sites and cultivars. The Cd bioconcentration factors (BCFs) and Cd removals by the field-grown A. carambola differed significantly among sites but not among cultivars. Nonetheless, all four carambola cultivars investigated were able to accumulate considerably high concentrations of Cd in their shoots, which indicated that the 4-yr-old carambola stands could remove 0.3 to 51.8% of the total Cd content in the top 20-cm soil layer. When cultured in Cd-spiked soils, the carambola cultivar Hua-Di always showed higher Cd tolerance than the other cultivars; however, this tendency was not confirmed by hydroponic experiment. The Cd BCFs of cultivar Thailand grown in soils with 6 and 12 mg Cd kg(-1) were highest among cultivars, whereas this trend was reversed at 120 mg Cd kg(-1) treatment. Nevertheless, the pot- and hydroponics-grown carambola cultivars generally showed higher capacities to tolerate and accumulate Cd, compared with the control species. The present results indicate that a strong ability to tolerate and accumulate Cd seems to be a trait at the species level in A. carambola, although some degree of variances in both Cd tolerance and accumulation exists among cultivars.

An Assessment of the Accumulation Potential of Pb, Zn and Cd by Avicennia marina (Forssk. Vierh. in Vamleshwar Mangroves, Gujarat, India

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Isaiah Nirmal KUMAR

2011-03-01

Full Text Available The study deals with the accumulation of Pb, Zn and Cd in an important mangrove species, Avicennia marina (Forssk. Vierh., in the Vamleshwar mangrove ecosystem, near Narmada estuary, West coast of Gujarat, India with height differences of 0.5, 1.5, 2.5 meters and carried out under field conditions during October, 2009. The site was located on 213011.55 N latitude and 724353.68 E longitude. Mangrove receives heavy metal pollution from upstream areas of Narmada estuary and highly populated settlements. However, little is known about the capacity of mangrove plants to take up and store heavy metals in them. Water, sediment and plant parts such as roots, stems and leaves were analyzed for finding the trace metal accumulation of different height groups by Inductive Coupled Plasma Analyser (ICPA. Amount of the content of metals found in the water, sediment and plant parts were in the order of Pb>Zn>Cd. The average contents of heavy metals in the waters were 57.83 mg l-1 for Pb, 3.89 83 mg l-1 for Zn and 0.42 mg l-1 for Cd. It was observed that the average contents of Pb (73.6 mg l-1, Zn (8.1 mg l-1 and Cd (0.73 mg l-1 in the sediments were below the critical soil concentrations. The concentrations of heavy metals in different parts of Avicennia marina were in the order Roots>stem>leaf except for Cd, but Cd found higher in leaf. The ranges of the content of heavy metals in plants were 18.5-102.2 mg l-1 for Pb, 3.5-19.5 mg l-1 for Zn and 0.2-4.1 mg l-1 for Cd. The concentrations of all heavy metals in Avicennia marina except Pb were falling within the normal range and were much more in the plants have the highest height. The present study has shown the potential of Avicennia marina as a phytoremediation species for selected heavy metals in many mangrove ecosystems.

Chemotherapeutic Effect of CD147 Antibody-labeled Micelles Encapsulating Doxorubicin Conjugate Targeting CD147-Expressing Carcinoma Cells.

Science.gov (United States)

Asakura, Tadashi; Yokoyama, Masayuki; Shiraishi, Koichi; Aoki, Katsuhiko; Ohkawa, Kiyoshi

2018-03-01

CD147 (basigin/emmprin) is expressed on the surface of carcinoma cells. For studying the efficacy of CD147-targeting medicine on CD147-expressing cells, we studied the effect of anti-CD147-labeled polymeric micelles (CD147ab micelles) that encapsulated a conjugate of doxorubicin with glutathione (GSH-DXR), with specific accumulation and cytotoxicity against CD147-expressing A431 human epidermoid carcinoma cells, Ishikawa human endometrial adenocarcinoma cells, and PC3 human prostate carcinoma cells. By treatment of each cell type with CD147ab micelles for 1 h, a specific accumulation of CD147ab micelles in CD147-expressing cells was observed. In addition, the cytotoxicity of GSH-DXR-encapsulated micelles against each cell type was measured by treatment of the micelles for 1 h. The cytotoxic effect of CD147ab micelles carrying GSH-DXR was 3- to 10-fold higher for these cells than that of micelles without GSH-DXR. These results suggest that GSH-DXR-encapsulated CD147ab micelles could serve as an effective drug delivery system to CD147-expressing carcinoma cells. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Antagonistic effects of cadmium on lead accumulation in pregnant and non-pregnant mice

International Nuclear Information System (INIS)

Smith, Euan; Gancarz, Dorota; Rofe, Allan; Kempson, Ivan M.; Weber, John; Juhasz, Albert L.

2012-01-01

Highlights: ► We investigate the exposure of pregnant and non-pregnant mice to cadmium (Cd) on lead (Pb) contaminated soil. ► We examine the changes in lead accumulation in mice due to the presence of cadmium in soil. ► Lead accumulation is higher in pregnant compared to non-pregnant mice. ► Cadmium decreases lead accumulation in all mice irrespective of status. - Abstract: People are frequently exposed to combinations of contaminants but there is a paucity of data on the effects of mixed contaminants at low doses. This study investigated the influence of cadmium (Cd) on lead (Pb) accumulation in pregnant and non-pregnant mice following exposure to contaminated soil. Exposure to Pb from contaminated soils increased Pb accumulation in both pregnant and non-pregnant mice compared to unexposed control animals (pregnant and non-pregnant). Lead accumulation in the liver and kidneys of exposure pregnant mice (40 ± 15 mg Pb kg −1 ) was significantly higher (P −1 ). The presence of Cd in contaminated soil had a major effect on the Pb and Fe accumulation in the kidneys and liver, respectively. This study shows that Pb uptake is mediated by the presence of Cd in the co-contaminated soil and demonstrates that further research is required to investigate the influence of co-contaminants on human exposure at sub-chronic concentrations.

Toxic effects of two sources of dietborne cadmium on the juvenile cobia, Rachycentron canadum L. and tissue-specific accumulation of related minerals

International Nuclear Information System (INIS)

Liu, Kang; Chi, Shuyan; Liu, Hongyu; Dong, Xiaohui; Yang, Qihui; Zhang, Shuang; Tan, Beiping

2015-01-01

Highlights: • CdCl 2 –Cd showed a higher toxicity than SVM-Cd for cobia. • Cd accumulation in cobia fed diets contaminated SVM-Cd was higher than in cobia fed diets contaminated CdCl 2 –Cd. • Cd accumulation in tissues of cobia fed both types of Cd was kidney > liver > intestine > gill muscle. • Dietborne Cd decreased the Fe concentration in kidney and liver, Ca concentrations in vertebra and scale. - Abstract: In the present study, juvenile cobia, Rachycentron canadum L. were fed diets contaminated by two different sources of cadmium: squid viscera meal (SVM-Cd, organic form) and cadmium chloride (CdCl 2 –Cd, inorganic form). The Cd concentrations in fish diet were approximate 3.0, 5.0 and 10.0 mg Cd kg −1 for both inorganic and organic forms. In the control diet (0.312 mg Cd kg −1 diet, Cd mainly come from fish meal), no cadmium was added. The experiment lasted for 16 weeks and a statistically significant inverse relationship was observed between specific growth rate (SGR) and the concentration of dietary Cd. The SGR of cobia fed a diet with SVM-Cd increased at the lowest doses and decreased with the increasing level of dietary SVM. Fish fed diet contaminated SVM-Cd had significantly higher SGR than those fed diets contaminated CdCl 2 –Cd among the high Cd level diets treatments. The dietary Cd levels also significantly affected the survival rate of the fish. Among the hematological characteristics and plasma constituents, glutamic-pyruvic transaminase activities and alkaline phosphatase activities in serum and liver increased and hepatic superoxide dismutase activity decreased with the increasing dietary Cd levels. The cobia fed diet contaminated by high level of CdCl 2 –Cd had significantly higher ALP activity than cobia fed diet contaminated by high level of SVM-Cd. The results from these studies indicate no differences in toxicity response to dietborne SVM-Cd and CdCl 2 –Cd at a low level of Cd. However, at a higher level, cobia was

Combined effects of elevated CO_2 and Cd-contaminated water on growth, photosynthetic response, Cd accumulation and thiolic components status in Lemna minor L

International Nuclear Information System (INIS)

Pietrini, F.; Bianconi, D.; Massacci, A.; Iannelli, M.A.

2016-01-01

Highlights: • Elevated CO_2 did not affect the ability of L. minor plants to accumulate Cd in their tissues. • Elevated CO_2 decreased Cd toxicity in L. minor plants by increasing photosynthesis. • Elevated CO_2 reduced Cd toxicity in duckweed by enhancing antioxidant system. - Abstract: The objective of this study was to investigate the combined effects of elevated CO_2 and cadmium (Cd) treatments on growth, photosynthetic efficiency and phytoremediation ability in Lemna minor L. Plants of L. minor were exposed to different Cd concentrations (0, 1.5, 2.5 and 5 mg L"−"1 Cd) for periods of 24, 48 and 72 h at ambient (AC) and at elevated (EC) CO_2 (350 and 700 ppm, respectively). Cadmium concentration, bioconcentration factor, enzyme activities and thiols content enhanced in plants with the increase of Cd treatments, time of exposure and at both CO_2 levels. Glutathione levels increased only at AC. Growth, photosynthetic and chlorophyll fluorescence parameters, and the reduced glutathione to oxidized glutathione ratio declined in plants with increasing exposure time, Cd treatments and at both CO_2 levels. Our results suggested that the alleviation of toxicity, at low Cd doses, observed in L. minor grown at EC is dependent on both increased photosynthesis and an enhanced antioxidant capacity.

Relationship between Pb and Cd accumulations in house crow, their habitat, and food content from Klang area, Peninsular Malaysia.

Science.gov (United States)

Janaydeh, Mohammed; Ismail, Ahmad; Omar, Hishamuddin; Zulkifli, Syaizwan Zahmir; Bejo, Mohd Hair; Aziz, Nor Azwady Abd

2017-12-27

Heavy metal pollution has become a global concern due to accumulation in tissue and transferable effects to humans via the food chain. This study focused on monitoring the accumulation of cadmium (Cd) and lead (Pb) in surface soil and body content: bone, heart, brain, liver, lung, muscle, kidney, feathers, feces, and gizzard contents of house crow Corvus splendens in the Klang region, Malaysia. The results revealed the occurrence of Pb and Cd in all biological samples from house crows, food contents, and surface soil samples. Heart and kidney accrued high amounts of Cd, while high amounts of Pb were found to accumulate in bones and feathers. Major discrepancies were also discovered in the concentrations of metals between juvenile and adults, as well as female and male bird samples. Concentrations of Pb and Cd in house crow internal tissues correlated significantly with that of bird feathers, but none could be established with that of surface soil. In addition, a significant correlation was observed between Pb concentration in the internal tissues to that of the feces, but the same was not the case when compared with the surface soil concentration. Metal accrual in the house crows feathers and feces may be through a long-term transmission via the food chain, which are eliminated from feathers via molting. This may suggest the utility of molted breast feathers of house crow in the bio-monitoring of Cd and Pb contamination, whereas feces of house crow appear only to be suitable for the bio-monitoring of Pb contamination.

Cadmium translocation and accumulation in developing barley grains

DEFF Research Database (Denmark)

Chen, Fei; Wu, Feibo; Dong, Jing

2007-01-01

 Soil cadmium (Cd) contamination has posed a serious problem for safe food production and become a potential agricultural and environmental hazard worldwide. In order to study the transport of Cd into the developing grains, detached ears of two-rowed barley cv. ZAU 3 were cultured in Cd stressed...... of detached spike showed increase Cd accumulation for 5 days, followed by sharp decrease till day 10 and increase again after 12.5 days. Awn-removal and stem-girdling markedly decreased Cd concentration in grains, and sucrose or zinc (Zn) addition to the medium and higher relative humidity (RH) also induced...

Toxic effects of two sources of dietborne cadmium on the juvenile cobia, Rachycentron canadum L. and tissue-specific accumulation of related minerals

Energy Technology Data Exchange (ETDEWEB)

Liu, Kang [Laboratory of Aquatic Animal Nutrition and Feed, College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong (China); Guangdong Yuehai Feed Group Co., Ltd., Zhanjiang, Guangdong (China); Chi, Shuyan; Liu, Hongyu; Dong, Xiaohui; Yang, Qihui; Zhang, Shuang [Laboratory of Aquatic Animal Nutrition and Feed, College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong (China); Tan, Beiping, E-mail: bptan@126.com [Laboratory of Aquatic Animal Nutrition and Feed, College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong (China)

2015-08-15

Highlights: • CdCl{sub 2}–Cd showed a higher toxicity than SVM-Cd for cobia. • Cd accumulation in cobia fed diets contaminated SVM-Cd was higher than in cobia fed diets contaminated CdCl{sub 2}–Cd. • Cd accumulation in tissues of cobia fed both types of Cd was kidney > liver > intestine > gill muscle. • Dietborne Cd decreased the Fe concentration in kidney and liver, Ca concentrations in vertebra and scale. - Abstract: In the present study, juvenile cobia, Rachycentron canadum L. were fed diets contaminated by two different sources of cadmium: squid viscera meal (SVM-Cd, organic form) and cadmium chloride (CdCl{sub 2}–Cd, inorganic form). The Cd concentrations in fish diet were approximate 3.0, 5.0 and 10.0 mg Cd kg{sup −1} for both inorganic and organic forms. In the control diet (0.312 mg Cd kg{sup −1} diet, Cd mainly come from fish meal), no cadmium was added. The experiment lasted for 16 weeks and a statistically significant inverse relationship was observed between specific growth rate (SGR) and the concentration of dietary Cd. The SGR of cobia fed a diet with SVM-Cd increased at the lowest doses and decreased with the increasing level of dietary SVM. Fish fed diet contaminated SVM-Cd had significantly higher SGR than those fed diets contaminated CdCl{sub 2}–Cd among the high Cd level diets treatments. The dietary Cd levels also significantly affected the survival rate of the fish. Among the hematological characteristics and plasma constituents, glutamic-pyruvic transaminase activities and alkaline phosphatase activities in serum and liver increased and hepatic superoxide dismutase activity decreased with the increasing dietary Cd levels. The cobia fed diet contaminated by high level of CdCl{sub 2}–Cd had significantly higher ALP activity than cobia fed diet contaminated by high level of SVM-Cd. The results from these studies indicate no differences in toxicity response to dietborne SVM-Cd and CdCl{sub 2}–Cd at a low level of Cd

Antagonistic effects of cadmium on lead accumulation in pregnant and non-pregnant mice

Energy Technology Data Exchange (ETDEWEB)

Smith, Euan, E-mail: euan.smith@unisa.edu.au [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Gancarz, Dorota; Rofe, Allan [Veterinary Services Division, Institute of Medical and Veterinary Science, Gilles Plains, SA 5086 (Australia); Kempson, Ivan M. [Institute of Physics, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan (China); Weber, John; Juhasz, Albert L. [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia)

2012-01-15

Highlights: Black-Right-Pointing-Pointer We investigate the exposure of pregnant and non-pregnant mice to cadmium (Cd) on lead (Pb) contaminated soil. Black-Right-Pointing-Pointer We examine the changes in lead accumulation in mice due to the presence of cadmium in soil. Black-Right-Pointing-Pointer Lead accumulation is higher in pregnant compared to non-pregnant mice. Black-Right-Pointing-Pointer Cadmium decreases lead accumulation in all mice irrespective of status. - Abstract: People are frequently exposed to combinations of contaminants but there is a paucity of data on the effects of mixed contaminants at low doses. This study investigated the influence of cadmium (Cd) on lead (Pb) accumulation in pregnant and non-pregnant mice following exposure to contaminated soil. Exposure to Pb from contaminated soils increased Pb accumulation in both pregnant and non-pregnant mice compared to unexposed control animals (pregnant and non-pregnant). Lead accumulation in the liver and kidneys of exposure pregnant mice (40 {+-} 15 mg Pb kg{sup -1}) was significantly higher (P < 0.05) than concentrations detected in control pregnant mice (<1 mg Pb kg{sup -1}). The presence of Cd in contaminated soil had a major effect on the Pb and Fe accumulation in the kidneys and liver, respectively. This study shows that Pb uptake is mediated by the presence of Cd in the co-contaminated soil and demonstrates that further research is required to investigate the influence of co-contaminants on human exposure at sub-chronic concentrations.

Prosopis juliflora--a green solution to decontaminate heavy metal (Cu and Cd) contaminated soils.

Science.gov (United States)

Senthilkumar, P; Prince, W S P M; Sivakumar, S; Subbhuraam, C V

2005-09-01

Soil and plant samples (root and shoot) of Prosopis juliflora were collected in the vicinity of metal based foundry units in Coimbatore and assessed for their heavy metal content (Cu and Cd) to ascertain the use of P. juliflora as a green solution to decontaminate soils contaminated with Cu and Cd. The results showed that Cu and Cd content was much higher in plant components compared to their extractable level in the soil. Furthermore, there exist a strong correlation between the distance of the sources of industrial units and accumulation of heavy metals in plants. Accumulation of Cd in roots is comparatively higher than that of shoots. However, in case of Cu no such clear trend is seen. Considering the accumulation efficiency and tolerance of P. juliflora to Cd and Cu, this plant can be explored further for the decontamination of metal polluted soils. On the other hand, in view of heavy metal accumulate the practice of providing foliage and pods as fodder for live stock should be avoided.

Influence of iron plaque on uptake and accumulation of Cd by rice (Oryza sativa L.) seedlings grown in soil.

Science.gov (United States)

Liu, Houjun; Zhang, Junling; Christie, Peter; Zhang, Fusuo

2008-05-15

Iron plaque is ubiquitously formed on the root surfaces of rice. However, little is known about the role of iron plaque in Cd movement from soil to the plant aboveground parts. A pot experiment was conducted to investigate the influence of iron plaque in Cd uptake and accumulation by rice seedlings in soil. Rice seedlings were pre-cultivated in solution culture for 16 days. Two seedlings were transplanted in a nylon bag containing no substrate but surrounded by soil amended with Fe and Cd combined at rates of 0, 1, or 2 g Fe kg(-1) and 0, 2.0, or 10 mg Cd kg(-1) soil. Fe was added to induce different amounts of iron plaque, and Cd to simulate Cd-polluted soils. Plants were grown for a further 43 days and then harvested. The length of the longest leaf and SPAD values of the newly mature leaves were measured during plant growth. Fe and Cd concentrations were determined in dithionite-citrate-bicarbonate (DCB) soil extracts and in plant roots and shoots. Shoot and root dry weights were significantly affected by Fe supply level but not by added Cd. Root dry weight declined with increasing Fe supply but shoot dry weight decreased at 2 g Fe kg(-1) and increased at 1 g Fe kg(-1) (except at 2 mg Cd kg(-1)). The length of the longest leaf and SPAD values of the newly mature leaves were significantly affected by plant growth stage and added Fe and Cd. Fe tended to diminish the negative effect of Cd on these two parameters. Cd concentrations in DCB extracts increased with increasing Cd and Fe supply. In contrast, external Fe supply markedly reduced shoot and root Cd concentrations and there was generally no significant difference between the two Fe supply levels. Shoot and root Cd concentrations increased with increasing Cd addition. Root Cd concentrations were negatively correlated with root Fe concentrations. The proportion of Cd in DCB extracts was significantly lower than in roots or shoots. The results indicate that enhanced Fe uptake by plants can diminish the negative

Cadmium speciation and accumulation in periphyton in a small stream with dynamic concentration variations

Energy Technology Data Exchange (ETDEWEB)

Bradac, Philippe [Eawag, Swiss Federal Institute of Aquatic Science and Technology, P.O. Box 611, CH-8600 Duebendorf (Switzerland); ETH, Swiss Federal Institute of Technology, Department of Environmental Sciences, CH-8092 Zurich (Switzerland); Wagner, Bettina; Kistler, David; Traber, Jacqueline; Behra, Renata [Eawag, Swiss Federal Institute of Aquatic Science and Technology, P.O. Box 611, CH-8600 Duebendorf (Switzerland); Sigg, Laura, E-mail: laura.sigg@eawag.c [Eawag, Swiss Federal Institute of Aquatic Science and Technology, P.O. Box 611, CH-8600 Duebendorf (Switzerland); ETH, Swiss Federal Institute of Technology, Department of Environmental Sciences, CH-8092 Zurich (Switzerland)

2010-03-15

Accumulation of cadmium in periphyton was investigated under field conditions while Cd concentration and speciation were dynamically varying in a small stream during rain events. Speciation in water was determined in situ by diffusion gradient in thin-films (DGT) and by modeling of complexation with fulvic acids. During the rain events, dissolved Cd concentrations increased from 0.17 nM to 0.27-0.36 nM, and 70-97% were DGT-labile. Cd content in periphyton closely followed Cd concentrations in water, despite higher concentrations of Zn and Mn, and may be controlled by either free or DGT-labile Cd concentrations. Decrease of Cd content in periphyton after the rain events was slower than the decrease of Cd concentration in water. Concentrations of Zn, Mn, Cu, Pb and Fe in periphyton also followed the dynamic variations of metal concentrations in water. Repeated exposure of periphyton to elevated dissolved Cd may lead to Cd accumulation. - Cadmium accumulation in periphyton was examined in a small stream during rain events in relation to Cd speciation.

Cadmium speciation and accumulation in periphyton in a small stream with dynamic concentration variations

International Nuclear Information System (INIS)

Bradac, Philippe; Wagner, Bettina; Kistler, David; Traber, Jacqueline; Behra, Renata; Sigg, Laura

2010-01-01

Accumulation of cadmium in periphyton was investigated under field conditions while Cd concentration and speciation were dynamically varying in a small stream during rain events. Speciation in water was determined in situ by diffusion gradient in thin-films (DGT) and by modeling of complexation with fulvic acids. During the rain events, dissolved Cd concentrations increased from 0.17 nM to 0.27-0.36 nM, and 70-97% were DGT-labile. Cd content in periphyton closely followed Cd concentrations in water, despite higher concentrations of Zn and Mn, and may be controlled by either free or DGT-labile Cd concentrations. Decrease of Cd content in periphyton after the rain events was slower than the decrease of Cd concentration in water. Concentrations of Zn, Mn, Cu, Pb and Fe in periphyton also followed the dynamic variations of metal concentrations in water. Repeated exposure of periphyton to elevated dissolved Cd may lead to Cd accumulation. - Cadmium accumulation in periphyton was examined in a small stream during rain events in relation to Cd speciation.

An Assessment of the Accumulation Potential of Pb, Zn and Cd by Avicennia marina (Forssk. Vierh. in Vamleshwar Mangroves, Gujarat, India

Directory of Open Access Journals (Sweden)

Isaiah Nirmal KUMAR

2011-03-01

Full Text Available The study deals with the accumulation of Pb, Zn and Cd in an important mangrove species, Avicennia marina (Forssk. Vierh., in the Vamleshwar mangrove ecosystem, near Narmada estuary, West coast of Gujarat, India with height differences of 0.5, 1.5, 2.5 meters and carried out under field conditions during October, 2009. The site was located on 21�30�11.55�� N latitude and 72�43�53.68�� E longitude. Mangrove receives heavy metal pollution from upstream areas of Narmada estuary and highly populated settlements. However, little is known about the capacity of mangrove plants to take up and store heavy metals in them. Water, sediment and plant parts such as roots, stems and leaves were analyzed for finding the trace metal accumulation of different height groups by Inductive Coupled Plasma Analyser (ICPA. Amount of the content of metals found in the water, sediment and plant parts were in the order of Pb>Zn>Cd. The average contents of heavy metals in the waters were 57.83 mg l-1 for Pb, 3.89 83 mg l-1 for Zn and 0.42 mg l-1 for Cd. It was observed that the average contents of Pb (73.6 mg l-1, Zn (8.1 mg l-1 and Cd (0.73 mg l-1 in the sediments were below the critical soil concentrations. The concentrations of heavy metals in different parts of Avicennia marina were in the order Roots>stem>leaf except for Cd, but Cd found higher in leaf. The ranges of the content of heavy metals in plants were 18.5-102.2 mg l-1 for Pb, 3.5-19.5 mg l-1 for Zn and 0.2-4.1 mg l-1 for Cd. The concentrations of all heavy metals in Avicennia marina except Pb were falling within the normal range and were much more in the plants have the highest height. The present study has shown the potential of Avicennia marina as a phytoremediation species for selected heavy metals in many mangrove ecosystems.

Role of P-glycoprotein on CD69+CD4+ cells in the pathogenesis of proliferative lupus nephritis and non-responsiveness to immunosuppressive therapy.

Science.gov (United States)

Tsujimura, Shizuyo; Adachi, Tomoko; Saito, Kazuyoshi; Tanaka, Yoshiya

2017-01-01

P-glycoprotein (P-gp) expression on activated lymphocytes in systemic lupus erythematosus (SLE) plays a role in active efflux of intracellular drugs, resulting in drug resistance. The role of P-gp-expressing lymphocytes in the pathogenesis of SLE remains unclear. The aim of this study was to determine the importance of P-gp + CD4 + cells in organ manifestations in refractory SLE. The proportion of P-gp + CD4 + cells was determined by flow cytometry in peripheral blood of patients with SLE (n=116) and healthy adults (n=10). Renal biopsy specimens were examined by immunohistochemistry for P-gp expression. CD69 is a marker of CD4 cell activation. The proportion of both P-gp-expressing CD4 + cells and CD69-expressing CD4 + cells in peripheral blood was higher in SLE than control. The proportion of P-gp + CD69 + CD4 + cells correlated with Systemic Lupus Erythematosus Disease Activity Index and was higher in poor responders to corticosteroids. Furthermore, the proportion of P-gp + CD69 + CD4 + cells was significantly higher in proliferative lupus nephritis (LN) with poor response to corticosteroids. The efficacy of immunosuppressive therapy depended on the regulation of the proportion of P-gp + CD69 + CD4 + cells. Marked accumulation of P-gp + CD4 + cells in renal interstitial tissue and high proportion of peripheral P-gp + CD69 + CD4 + cells were noted in patients with proliferative LN. The results showed high proportion of P-gp + CD69 + CD4 + cells in peripheral blood and their accumulation in renal tissue in patients with proliferative LN refractory to CS therapy, suggesting that P-gp expression on activated CD4 + T cells is a potentially useful marker for refractoriness to treatment and a novel target for treatment.

Percentages of CD4+CD161+ and CD4−CD8−CD161+ T Cells in the Synovial Fluid Are Correlated with Disease Activity in Rheumatoid Arthritis

Directory of Open Access Journals (Sweden)

Jinlin Miao

2015-01-01

Full Text Available Objective. CD161 has been identified as a marker of human IL-17-producing T cells that are implicated in the pathogenesis of rheumatoid arthritis (RA. This study aimed to investigate the potential link between the percentage of CD161+ T cells and disease activity in RA patients. Methods. Peripheral blood (PB from 54 RA patients and 21 healthy controls was evaluated. Paired synovial fluid (SF (n = 17 was analyzed. CD161 expression levels on CD4+, CD8+, and CD4−CD8− T cells were assessed by flow cytometry. Results. The percentage of CD4+CD161+ T cells in RA SF was higher than RA PB, and it was positively correlated with DAS28, erythrocyte sedimentation rate (ESR, and C-reactive protein (CRP. CD4−CD8−CD161+ T cell percentage was decreased in RA PB and was further reduced in RA SF, and its level in SF was inversely correlated with DAS28, ESR, and CRP. However, CD8+CD161+ T cell percentage was neither changed in RA PB and SF nor correlated with disease activity indices. Conclusion. An increased CD4+CD161+ T cell percentage and a decreased CD4−CD8−CD161+ T cell percentage are present in RA SF and are associated with disease activity, and the accumulation of CD4+CD161+ T cells in SF may contribute to the local inflammation of RA.

Functional components of the bacterial CzcCBA efflux system reduce cadmium uptake and accumulation in transgenic tobacco plants.

Science.gov (United States)

Nesler, Andrea; DalCorso, Giovanni; Fasani, Elisa; Manara, Anna; Di Sansebastiano, Gian Pietro; Argese, Emanuele; Furini, Antonella

2017-03-25

Cadmium (Cd) is a toxic trace element released into the environment by industrial and agricultural practices, threatening the health of plants and contaminating the food/feed chain. Biotechnology can be used to develop plant varieties with a higher capacity for Cd accumulation (for use in phytoremediation programs) or a lower capacity for Cd accumulation (to reduce Cd levels in food and feed). Here we generated transgenic tobacco plants expressing components of the Pseudomonas putida CzcCBA efflux system. Plants were transformed with combinations of the CzcC, CzcB and CzcA genes, and the impact on Cd mobilization was analysed. Plants expressing PpCzcC showed no differences in Cd accumulation, whereas those expressing PpCzcB or PpCzcA accumulated less Cd in the shoots, but more Cd in the roots. Plants expressing both PpCzcB and PpCzcA accumulated less Cd in the shoots and roots compared to controls, whereas plants expressing all three genes showed a significant reduction in Cd levels only in shoots. These results show that components of the CzcCBA system can be expressed in plants and may be useful for developing plants with a reduced capacity to accumulate Cd in the shoots, potentially reducing the toxicity of food/feed crops cultivated in Cd-contaminated soils. Copyright © 2016 Elsevier B.V. All rights reserved.

Accumulation of Pb, Cd and Zn from contaminated soil to various plants and evaluation of soil remediation with indicator plant (Plantago lanceolata L.)

Energy Technology Data Exchange (ETDEWEB)

Zupan, M.; Lobnik, F.; Kadunc, V. [Ljubljana Univ. (Slovenia). Agronomy Dept., Center for Soil and Environmental Science; Hudnik, V. [National Institute of Chemistry Hajdrihova 19, Ljubljana (Slovenia)

1997-12-31

The accumulation of cadmium, lead, and zinc by different major cultivated plants from soils contaminated with heavy metals, is presented. The vegetables, crops, and the indicator plant narrow leaf plantain (Plantago lanceolata L.) were used in a field experiment including 3 areas with different levels of pollution. The highest concentrations of heavy metals were observed in edible green parts of vegetables (endive, spinach, lettuce) and roots (carrot, red beet, radish). The heavy metal content in leguminous plants (pods and seeds) was very low compared to high soil concentrations. Wheat and maize showed lower concentrations in grains and kernels than in green parts. Lime and vermiculite were used for reduction of Cd availability to plants in polluted soil. The Cd concentration decreased in the narrow leaf plantain in the presence of both lime and vermiculite in acid soil. In the higher-pH soil the Cd availability to spinach was greatly reduced in the presence of vermiculite

Spatial pattern of heavy metals accumulation risk in urban soils of Beijing and its influencing factors

International Nuclear Information System (INIS)

Liu, Rui; Wang, Meie; Chen, Weiping; Peng, Chi

2016-01-01

Accumulations of heavy metals in urban soils are highly spatial heterogeneity and affected by multiple factors including soil properties, land use and pattern, population and climatic conditions. We studied accumulation risks of Cd, Cu, Pb and Zn in unban soils of Beijing and their influencing based on the regression tree analysis and a GIS-based overlay model. Result shows that Zinc causes the most extensive soil pollution and Cu result in the most acute soil pollution. The soil's organic carbon content and CEC and population growth are the most significant factors affecting heavy metal accumulation. Other influence factors in land use pattern, urban landscape, and wind speed also contributed, but less pronounced. The soils in areas with higher degree of urbanization and surrounded by intense vehicular traffics have higher accumulation risk of Cd, Cu, Pb, and Zn. - Highlights: • Zn accumulations were the most extensive and Cu accumulations were the most acute. • Accumulations of Cd, Cu, Pb and Zn in urban soils were caused by different sets of influence factors. • Soil's organic carbon content and CEC and population growth were the most significant factors. • Accumulation risks were highly related with urbanization level and human activities. - A combined approach of employing geographical information systems and regression tree analyses identify the potential risks of accumulation Cd, Cu, Pb, and Zn in urban soils according to soil properties, urban land use patterns, urban landscape, demographics, and microclimatic conditions.

Accumulation of Heavy Metals in Crayfish and Fish from Selected Czech Reservoirs

Directory of Open Access Journals (Sweden)

Iryna Kuklina

2014-01-01

Full Text Available To evaluate the accumulation of aluminium, cadmium, chromium, copper, lead, mercury, nickel, and zinc in crayfish and fish organ tissues, specimens from three drinking water reservoirs (Boskovice, Landštejn, and Nová Říše and one contaminated site (Darkovské moře in the Czech Republic were examined. Crayfish hepatopancreas was confirmed to be the primary accumulating site for the majority of metals (Cu > Zn > Ni > Cd > Cr, while Hg and Cr were concentrated in abdominal muscle, and Al and Pb were concentrated in gill. Metals found in Nová Říše specimens included Cu > Zn > Ni and those found in Boskovice included Zn > Hg > Cr. Cd concentrations were observed only in Landštejn specimens, while contaminated Darkovské moře specimens showed the highest levels of accumulation (Cu > Al > Zn > Pb. The majority of evaluated metals were found in higher concentrations in crayfish: Cu > Al > Zn > Ni > Cr > Cd > Pb, with Hg being the only metal accumulating higher in fish. Due to accumulation similarities of Al in crayfish and fish gill, differences of Hg in muscle, and features noted for the remaining metals in examined tissues, biomonitoring should incorporate both crayfish and fish to produce more relevant water quality surveys.

Cadmium accumulation and strategies to avoid its toxicity in roots of the citrus rootstock Citrumelo

International Nuclear Information System (INIS)

Podazza, Griselda; Arias, Marta; Prado, Fernando E.

2012-01-01

Highlights: ► Cd induces oxidative stress, increasing the H 2 O 2 and O 2 · − generation. ► SOD, G-POD, CAT activities are enhanced by Cd. ► G-POD activity participates in Cd-induced lignin synthesis. ► Cd mainly accumulates in exodermis and vascular cylinder. ► Cd is mostly immobilized in roots, limiting its transport to aerial parts. - Abstract: In order to assess implications of Cd-induced oxidative stress in roots of the citrus rootstock Citrumelo, seedlings were hydroponically exposed to two relatively realistic Cd concentrations during 7 days. Our results showed that increasing Cd concentrations in external solution were associated with higher Cd accumulations in roots. At 5 μM Cd the accumulation of Cd in roots was over 70-f higher than in aerial part (stem + leaves). Malondialdehyde (MDA), superoxide radical (O 2 · − ), hydrogen peroxide (H 2 O 2 ) and lipoxygenase activity (LOX) increased in Cd-exposed roots, suggesting a metal-induced oxidative stress. The Cd treatment enhanced the activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and guaiacol-type peroxidase (G-POD), as well as the content of secondary metabolites i.e. soluble phenolics (SPs) and lignin. Histochemical analyses of roots showed that Cd, H 2 O 2 , (O 2 · − ), lignin and G-POD displayed a similar location pattern. Almost all analyzed parameters showed a similar dynamic tendency with increases under 5 μM Cd followed by decreases under 10 μM Cd, suggesting that a complex coordinated Cd-defensive mechanism is operating in Citrumelo roots exposed to environmental realistic Cd concentrations.

Combined effects of elevated CO{sub 2} and Cd-contaminated water on growth, photosynthetic response, Cd accumulation and thiolic components status in Lemna minor L

Energy Technology Data Exchange (ETDEWEB)

Pietrini, F.; Bianconi, D.; Massacci, A. [Institute of Agro-Environmental and Forest Biology, National Research Council of Italy, Via Salaria Km 29,300, 00015 Monterotondo Scalo, Roma (Italy); Iannelli, M.A., E-mail: adelaide.iannelli@ibba.cnr.it [Institute of Agricultural Biology and Biotechnology, National Research Council of Italy, Via Salaria Km 29,300, 00015 Monterotondo Scalo, Roma (Italy)

2016-05-15

Highlights: • Elevated CO{sub 2} did not affect the ability of L. minor plants to accumulate Cd in their tissues. • Elevated CO{sub 2} decreased Cd toxicity in L. minor plants by increasing photosynthesis. • Elevated CO{sub 2} reduced Cd toxicity in duckweed by enhancing antioxidant system. - Abstract: The objective of this study was to investigate the combined effects of elevated CO{sub 2} and cadmium (Cd) treatments on growth, photosynthetic efficiency and phytoremediation ability in Lemna minor L. Plants of L. minor were exposed to different Cd concentrations (0, 1.5, 2.5 and 5 mg L{sup −1} Cd) for periods of 24, 48 and 72 h at ambient (AC) and at elevated (EC) CO{sub 2} (350 and 700 ppm, respectively). Cadmium concentration, bioconcentration factor, enzyme activities and thiols content enhanced in plants with the increase of Cd treatments, time of exposure and at both CO{sub 2} levels. Glutathione levels increased only at AC. Growth, photosynthetic and chlorophyll fluorescence parameters, and the reduced glutathione to oxidized glutathione ratio declined in plants with increasing exposure time, Cd treatments and at both CO{sub 2} levels. Our results suggested that the alleviation of toxicity, at low Cd doses, observed in L. minor grown at EC is dependent on both increased photosynthesis and an enhanced antioxidant capacity.

The Effect of Pollination on Cd Phytoextraction From Soil by Maize (Zea mays L.).

Science.gov (United States)

Xu, Wending; Lu, Guining; Wang, Rui; Guo, Chuling; Liao, Changjun; Yi, Xiaoyun; Dang, Zhi

2015-01-01

A pot experiment was conducted to investigate the effects of pollination on cadmium (Cd) phytoextraction from soil by mature maize plants. The results showed that the unpollinated maize plants accumulated 50% more Cd than that of the pollinated plants, even though the dry weight of the former plants was 15% less than that of the latter plants. The Cd accumulation in root and leaf of the unpollinated maize plant was 0.47 and 0.89 times higher than that of the pollinated plant, respectively. The Cd concentration in the cob was significantly decreased because of pollination. Preventing pollination is a promising approach for enhancing the effectiveness of phytoextraction in Cd-contaminated soils by maize. This study suggested that in low Cd-contaminated soil pollination should be encouraged because accumulation of Cd in maize grains is very little and maize seeds can bring farmers economic benefits, while in high Cd-contaminated soil, inhibition of pollination can be applied to enhance phytoextraction of Cd from soil by maize plant.

The preferential accumulation of cadmium in the head portion of the freshwater planarian, Dugesia japonica (Platyhelminthes: Turbellaria).

Science.gov (United States)

Wu, Jui-Pin; Chen, Hon-Cheng; Li, Mei-Hui

2011-12-01

Free-living freshwater planarians are considered to have the potential for development as an experimental model for toxicological studies on xenobiotics, including metals. However, little was known about the distribution patterns of metals in the body of treated planarians. This study was conducted to determine the tissue distribution patterns of cadmium (Cd) in different body portions of the treated planarian, Dugesia japonica. Results showed that Cd accumulated in the head of planarians at a significantly higher concentration than in the tail. After examining the level of metallothionein (MT), we suggested that the tissue distribution pattern of Cd might be related to MT induction patterns. In contrast, in planarians treated with copper (Cu), neither the tissue accumulation of Cu nor the multiples of induction of MTs significantly differed between different portions. Furthermore, a higher Cd accumulation rate in the head of planarians caused more-severe oxidative stress to appear in this portion and also a higher susceptibility to a lethal concentration of Cd. Finally, both in vitro and in vivo acetylcholinesterase activities in both body portions of planarians were inhibited by Cd. The present study provides the first report that different metals are distributed in various body portions with different patterns in the planarian.

CD3+/CD16+CD56+ cell numbers in peripheral blood are correlated with higher tumor burden in patients with diffuse large B-cell lymphoma

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Anna Twardosz

2011-04-01

Full Text Available Diffuse large B-cell lymphoma is the commonest histological type of malignant lymphoma, andremains incurable in many cases. Developing more efficient immunotherapy strategies will require betterunderstanding of the disorders of immune responses in cancer patients. NKT (natural killer-like T cells wereoriginally described as a unique population of T cells with the co-expression of NK cell markers. Apart fromtheir role in protecting against microbial pathogens and controlling autoimmune diseases, NKT cells havebeen recently revealed as one of the key players in the immune responses against tumors. The objective of thisstudy was to evaluate the frequency of CD3+/CD16+CD56+ cells in the peripheral blood of 28 diffuse largeB-cell lymphoma (DLBCL patients in correlation with clinical and laboratory parameters. Median percentagesof CD3+/CD16+CD56+ were significantly lower in patients with DLBCL compared to healthy donors(7.37% vs. 9.01%, p = 0.01; 4.60% vs. 5.81%, p = 0.03, although there were no differences in absolute counts.The frequency and the absolute numbers of CD3+/CD16+CD56+ cells were lower in advanced clinical stagesthan in earlier ones. The median percentage of CD3+/CD16+CD56+ cells in patients in Ann Arbor stages 1–2 was5.55% vs. 3.15% in stages 3–4 (p = 0.02, with median absolute counts respectively 0.26 G/L vs. 0.41 G/L (p == 0.02. The percentage and absolute numbers of CD3+/CD16+CD56+ cells were significantly higher in DL-BCL patients without B-symptoms compared to the patients with B-symptoms, (5.51% vs. 2.46%, p = 0.04;0.21 G/L vs. 0.44 G/L, p = 0.04. The percentage of CD3+/CD16+CD56+ cells correlated adversely with serumlactate dehydrogenase (R= –445; p < 0.05 which might influence NKT count. These figures suggest a relationshipbetween higher tumor burden and more aggressive disease and decreased NKT numbers. But it remains tobe explained whether low NKT cell counts in the peripheral blood of patients with DLBCL are the result

[Accumulation Characteristics and Evaluation of Heavy Metals in Soil-Crop System Affected by Wastewater Irrigation Around a Chemical Factory in Shenmu County].

Science.gov (United States)

Qi, Yan-bing; Chu, Wan-lin; Pu, Jie; Liu, Meng-yun; Chang, Qing-rui

2015-04-01

Soil heavy metals Cu, Pb, Zn, and Cd, are regarded as "chemical time bombs" because of their propensity for accumulation in the soil and uptake by crops. This ultimately causes human toxicity in both the short and long-term, making farmland ecosystems dangerous to health. In this paper, accumulation and spatial variability of Cu, Zn, Pb and Cd in soil-crop system affected by wastewater irrigation around a chemical factor in northern Shaanxi province were analyzed. Results showed that wastewater irrigation around the chemical factory induced significant accumulation in soils compared with control areas. The average concentrations of available Cu and total Cu were 4.32 mg x kg(-1) and 38.4 mg x kg(-1), which were twice and 1.35 times higher than those of the control area, respectively. Soil Zn and Pb were slightly accumulated. Whereas soil Cd was significantly accumulated and was higher than the critical level of soil environmental quality (II), the available and total Cd concentrations were 0.248 mg x kg(-1) and 1.21 mg x kg(-1), which were 10 and 6.1 times higher than those of the control areas. No significant correlations were found between available and total heavy metals except between available Cd and total Cd. All the heavy metals were mainly accumulated in the top layer (0-10 cm). Spatially, soils and plants high in heavy metal concentration were distributed within the radius of about 100 m from the waste water outlet for Cu, Zn and Cd and about 200 m for Pb, and decreased exponentially with the distance from the factory. Affected by wastewater irrigation, contents of Cu, Pb and Cd in maize were 4.74, 0.129 and 0.036 mg x kg(-1) which were slightly higher than those in the control area. The content of Zn was similar to that in the control area. Affected by the vehicle exhaust, the over standard rate of Pb was 5.7% in maize. All the heavy metals did not show significant correlation between soil and crop, except Cd. The square correlation coefficients were 0

Lesional accumulation of CD163-expressing cells in the gut of patients with inflammatory bowel disease.

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Eleonora Franzè

Full Text Available Monocytes/macrophages displaying different markers of activation/differentiation infiltrate the inflamed gut of patients with inflammatory bowel diseases (IBD, but the role that each monocyte/macrophage subpopulation plays in the pathogenesis of IBD is not fully understood. The hemoglobin scavenger receptor CD163, a specific marker of monocytes/macrophages, has been associated with either anti-inflammatory or inflammatory functions of macrophages in several pathologies. In this study we examined the tissue distribution and function of CD163-expressing monocytes/macrophages in IBD. CD163 RNA and protein expression was more pronounced in IBD in comparison to normal controls, with no significant difference between Crohn's disease and Ulcerative colitis. In IBD, over-expression of CD163 was restricted to areas with active inflammation and not influenced by current therapy. Immunohistochemical analysis confirmed the accumulation of CD163-expressing cells in IBD, mostly around and inside blood vessels, thus suggesting that these cells are partly recruited from the systemic circulation. Indeed, FACS analysis of circulating mononuclear cells showed that the fractions of CD163-positive monocytes were increased in IBD patients as compared to controls. Functionally, interleukin-6 up-regulated CD163 expression in lamina propria mononuclear cells and mucosal explants of normal subjects. In IBD blood and mucosal cell cultures, cross-linking of CD163 with a specific monoclonal anti-CD163 antibody enhanced tumor necrosis factor-α synthesis. These findings indicate that IBD mucosa is abundantly infiltrated with CD163-positive cells, which could contribute to amplify the inflammatory cytokine response.

Cadmium accumulation and strategies to avoid its toxicity in roots of the citrus rootstock Citrumelo

Energy Technology Data Exchange (ETDEWEB)

Podazza, Griselda [Instituto de Ecologia, Fundacion Miguel Lillo, Miguel Lillo 251, CP 4000, Tucuman (Argentina); Arias, Marta [Catedra de Anatomia Vegetal, Facultad de Ciencias Naturales e IML, Miguel Lillo 205, CP 4000, Tucuman (Argentina); Prado, Fernando E., E-mail: prad@arnet.com.ar [Catedra de Fisiologia Vegetal, Facultad de Ciencias Naturales e IML, Miguel Lillo 205, CP 4000, Tucuman (Argentina)

2012-05-15

Highlights: Black-Right-Pointing-Pointer Cd induces oxidative stress, increasing the H{sub 2}O{sub 2} and O{sub 2}{center_dot}{sup -} generation. Black-Right-Pointing-Pointer SOD, G-POD, CAT activities are enhanced by Cd. Black-Right-Pointing-Pointer G-POD activity participates in Cd-induced lignin synthesis. Black-Right-Pointing-Pointer Cd mainly accumulates in exodermis and vascular cylinder. Black-Right-Pointing-Pointer Cd is mostly immobilized in roots, limiting its transport to aerial parts. - Abstract: In order to assess implications of Cd-induced oxidative stress in roots of the citrus rootstock Citrumelo, seedlings were hydroponically exposed to two relatively realistic Cd concentrations during 7 days. Our results showed that increasing Cd concentrations in external solution were associated with higher Cd accumulations in roots. At 5 {mu}M Cd the accumulation of Cd in roots was over 70-f higher than in aerial part (stem + leaves). Malondialdehyde (MDA), superoxide radical (O{sub 2}{center_dot}{sup -}), hydrogen peroxide (H{sub 2}O{sub 2}) and lipoxygenase activity (LOX) increased in Cd-exposed roots, suggesting a metal-induced oxidative stress. The Cd treatment enhanced the activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and guaiacol-type peroxidase (G-POD), as well as the content of secondary metabolites i.e. soluble phenolics (SPs) and lignin. Histochemical analyses of roots showed that Cd, H{sub 2}O{sub 2}, (O{sub 2}{center_dot}{sup -}), lignin and G-POD displayed a similar location pattern. Almost all analyzed parameters showed a similar dynamic tendency with increases under 5 {mu}M Cd followed by decreases under 10 {mu}M Cd, suggesting that a complex coordinated Cd-defensive mechanism is operating in Citrumelo roots exposed to environmental realistic Cd concentrations.

Study on accumulation of Fe, Pb, Zn, Ni and Cd in Nerita lineata and Thais bitubercularis from Tanjung Harapan and Teluk Kemang, Malaysia.

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Tengku

2017-01-01

Full Text Available The presence of Cd, Cu, Zn, Ni, Fe, Al, Zn, Mn, Cr, and Sn were attributed to metal industries. Cu contamination was associated with piggery industry. Shipping activities contribute to elevated levels of Pb, Cu and As. Elevated levels of metals in the sediments are attributed to anthropogenic activities. Samples were collected in April 2012 and analysed using inductively coupled plasma mass spectrometry (ICP-MS. Fe is the most abundant metal in the tissue and shell compared to the rest of the metals. The concentrations of heavy metals in the soft tissues of Nerita lineata taken from Tanjung Harapan follow this order: Fe > Zn > Ni > Cu > Cd while in Thais bitubercularis, the metal concentrations were higher following the order of Fe > Zn > Cu > Ni > Cd. The samples taken from Teluk Kemang were higher and exhibited different trend for both organisms. Results from this study are useful for further exploration of Thais bitubercularis as accumulators of Cu, Cd, and Zn. For recommendation, more studies on monitoring the concentration level of heavy metals in marine environment should be done regularly and increase numbers of samples use to biomonitor the heavy metals in marine environment as it is important to have information or data regarding the quality of marine environment in order to control pollution such as water pollution from being contaminated with heavy metals. This is essential as the pollutants emit in the marine environment may affect marine lives as well as human’s health

Heavy metal tolerance and accumulation of Triarrhena sacchariflora, a large amphibious ornamental grass.

Science.gov (United States)

Tian, R N; Yu, S; Wang, S G; Zhang, Y; Tang, J Y; Liu, Y L; Nie, Y H

2013-01-01

In this study, we report the tolerance and accumulation of Triarrhena sacchariflora to copper (Cu) and cadmium (Cd). The results show that T. sacchariflora had strong tolerance to Cu and Cd stress. The tolerance indexes (TI) were greater than 0.5 for all treatments. The bioconcentration factors (BCFs) to Cu and Cd were both above 1.0. The accumulation ability of roots was stronger than that of shoots, and ranges of BCF to Cu and Cd in roots were 37.89-79.08 and 83.96-300.57, respectively. However, the translocation ability to Cu and Cd was weak, with more than 86% of Cu or Cd accumulated in roots, suggesting an exclusion strategy for heavy metal tolerance. The uptake efficiency (UE) and translocation efficiency (TE) to Cu and Cd increased linearly as the Cu and Cd concentration in the substrate increased. UE was higher than TE, with a maximum of 2,118.90 μg g(-1) root dry weight (DW) (50 mg L(-1) Cu) and 1,847.51 μg g(-1) root DW (20 mg L(-1)Cd), respectively. The results indicate that T. sacchariflora is a Cu- and Cd-tolerant non-hyperaccumulator plant, suggesting that T. sacchariflora could play an important role in phytoremediation in areas contaminated with Cu and Cd.

Hepatic fat accumulation and regulation of FAT/CD36: an effect of hepatic irradiation

Science.gov (United States)

Martius, Gesa; Alwahsh, Salamah Mohammad; Rave-Fränk, Margret; Hess, Clemens Friedrich; Christiansen, Hans; Ramadori, Giuliano; Malik, Ihtzaz Ahmed

2014-01-01

Irradiation is known to induce inflammation and affect fat metabolic pathways. The current study investigates hepatic fat accumulation and fatty acid transportation in a rat model of single dose liver irradiation (25-Gy). Rat livers were selectively irradiated in-vivo (25-Gy), sham-irradiated rats served as controls. Hepatic lipids were studied by colorimetric assays in liver and serum. Intracellular lipids, protein and mRNA were studied by Nile red staining, immunohistology, Western Blot analysis and RT-PCR in liver, respectively. Changes in FAT/CD36 expression were studied in-vitro in a human monocyte cell line U937 after irradiation in presence or absence of infliximab (IFX). Nile Red staining of liver cryosections showed a quick (12-48 h) increase in fat droplets. Accordingly, hepatic triglycerides (TG) and free fatty acids (FFA) were elevated. An early increase (3-6 h) in the serum level of HDL-C, TG and cholesterol was measured after single dose irradiation followed by a decrease thereafter. Furthermore, expression of the fat transporter protein FAT/CD36 was increased, immunohistochemistry revealed basolateral and cytoplasmic expression in hepatocytes. Moreover, apolipoprotein-B100, -C3 and enzymes (acetyl-CoA carboxylase, lipoprotein-lipase, carnitine-palmitoyltransferase, malonyl-CoA-decarboxylase) involved in fat metabolism were induced at 12-24 h. Early activation of the NFkβ pathway (IκBα) by TNF-α was seen, followed by a significant elevation of serum markers for liver damage (AST and GLDH). TNF-α blockage by anti-TNF-α in cell culture (U937) prevented the increase of FAT/CD36 caused by irradiation. Selective liver irradiation is a model for rapid induction of steatosis hepatis and fat accumulation could be triggered by irradiation-induced inflammatory mediators (e.g. TNF-α). PMID:25197426

Toxic effects of two sources of dietborne cadmium on the juvenile cobia, Rachycentron canadum L. and tissue-specific accumulation of related minerals.

Science.gov (United States)

Liu, Kang; Chi, Shuyan; Liu, Hongyu; Dong, Xiaohui; Yang, Qihui; Zhang, Shuang; Tan, Beiping

2015-08-01

In the present study, juvenile cobia, Rachycentron canadum L. were fed diets contaminated by two different sources of cadmium: squid viscera meal (SVM-Cd, organic form) and cadmium chloride (CdCl2-Cd, inorganic form). The Cd concentrations in fish diet were approximate 3.0, 5.0 and 10.0mg Cd kg(-1) for both inorganic and organic forms. In the control diet (0.312mg Cd kg(-1) diet, Cd mainly come from fish meal), no cadmium was added. The experiment lasted for 16 weeks and a statistically significant inverse relationship was observed between specific growth rate (SGR) and the concentration of dietary Cd. The SGR of cobia fed a diet with SVM-Cd increased at the lowest doses and decreased with the increasing level of dietary SVM. Fish fed diet contaminated SVM-Cd had significantly higher SGR than those fed diets contaminated CdCl2-Cd among the high Cd level diets treatments. The dietary Cd levels also significantly affected the survival rate of the fish. Among the hematological characteristics and plasma constituents, glutamic-pyruvic transaminase activities and alkaline phosphatase activities in serum and liver increased and hepatic superoxide dismutase activity decreased with the increasing dietary Cd levels. The cobia fed diet contaminated by high level of CdCl2-Cd had significantly higher ALP activity than cobia fed diet contaminated by high level of SVM-Cd. The results from these studies indicate no differences in toxicity response to dietborne SVM-Cd and CdCl2-Cd at a low level of Cd. However, at a higher level, cobia was more sensitive to dietborne CdCl2-Cd than SVM-Cd. Based on quadratic regression of SGR, The Cd concentrations was 3.617mg kg(-1) in the optimal diet, Cd source was SVM (126mg Cd kg(-1) in SVM) which stimulate the growth of cobia and the added level was determined to be 26.7g kg(-1) diet in the present study. Cd accumulations in the kidney of cobia fed both types of Cd were higher than other tissues, and the order of Cd accumulation in tissues

Asthma and gender impact accumulation of T cell subtypes

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Peters Stephen P

2010-07-01

Full Text Available Abstract Background The "Th2 hypothesis for asthma" asserts that an increased ratio of Th2:Th1 cytokine production plays an important pathogenic role in asthma. Although widely embraced, the hypothesis has been challenged by various empirical observations and has been described as overly simplistic. We sought to establish whether CD3+CD28-mediated and antigen-independent accumulation of type 1 and type 2 T cells differs significantly between nonasthmatic and asthmatic populations. Methods An ex vivo system was used to characterize the regulation of IFN-γ-producing (type 1 and IL-13-producing (type 2 T cell accumulation in response to CD3+CD28 and IL-2 stimulation by flow cytometry. Results IL-13-producing T cells increased in greater numbers in response to antigen-independent stimulation in peripheral blood lymphocytes from female atopic asthmatic subjects compared with male asthmatics and both male and female atopic non-asthmatic subjects. IFN-γ+ T cells increased in greater numbers in response to either antigen-independent or CD3+CD28-mediated stimulation in peripheral blood lymphocytes from atopic asthmatic subjects compared to non-asthmatic subjects, regardless of gender. Conclusions We demonstrate that T cells from asthmatics are programmed for increased accumulation of both type 2 and type 1 T cells. Gender had a profound effect on the regulation of type 2 T cells, thus providing a mechanism for the higher frequency of adult asthma in females.

Influence of earthworm mucus and amino acids on tomato seedling growth and cadmium accumulation

Energy Technology Data Exchange (ETDEWEB)

Zhang Shujie [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Hu Feng, E-mail: fenghu@njau.edu.c [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Li Huixin; Li Xiuqiang [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China)

2009-10-15

The effects on the growth of tomato seedlings and cadmium accumulation of earthworm mucus and a solution of amino acids matching those in earthworm mucus was studied through a hydroponic experiment. The experiment included four treatments: 5 mg Cd L{sup -1} (CC), 5 mg Cd L{sup -1} + 100 mL L{sup -1} earthworm mucus (CE), 5 mg Cd L{sup -1} + 100 mL L{sup -1} amino acids solution (CA) and the control (CK). Results showed that, compared with CC treatment, either earthworm mucus or amino acids significantly increased tomato seedling growth and Cd accumulation but the increase was much higher in the CE treatment compared with the CA treatment. This may be due to earthworm mucus and amino acids significantly increasing the chlorophyll content, antioxidative enzyme activities, and essential microelement uptake and transport in the tomato seedlings. The much greater increase in the effect of earthworm mucus compared with amino acid treatments may be due to IAA-like substances in earthworm mucus. - Earthworm mucus increased tomato seedlings growth and Cd accumulation through increasing chlorophyll content, antioxidative enzyme activities, and essential microelement accumulation.

Circulating CXCR5+CD4+ T cells participate in the IgE accumulation in allergic asthma.

Science.gov (United States)

Gong, Fang; Zhu, Hua-Yan; Zhu, Jie; Dong, Qiao-Jing; Huang, Xuan; Jiang, Dong-Jin

2018-05-01

The pathogenesis of allergic asthma is primarily characterized by abnormality in immunoglobin(Ig)E pathway, suggesting a possible role for follicular helper T cells (Tfh) in the genesis of excessive IgE accumulation. The blood chemokine (C-X-C motif) receptor 5 (CXCR)5 + CD4 + T cells, known as "circulating" Tfh, share common functional characteristics with Tfh cells from germinal centers. The aim of this study was to determine the phenotypes and functions of circulating CXCR5 + CD4 + T cells in allergic asthmatics. Here we found the frequency of the circulating CXCR5 + CD4 + T cells was raised in allergic asthma compared with healthy control (HC). Phenotypic assays showed that activated circulating CXCR5 + CD4 + T cells display the key features of Tfh cells, including invariably coexpressed programmed cell death (PD)-1 and inducible costimulator (ICOS). The frequency of interleukin IL-4 + -, IL-21 + -producing CXCR5 + CD4 + T cells was increased in allergic asthma patients compared with HC. Furthermore, sorted circulating CXCR5 + CD4 + T cells from allergic asthma patients boosted IgE production in coculture assay which could be inhibited by IL-4 or IL-21 blockage. Interestingly, IL-4 + -, IL-21 + -CXCR5 + CD4 + T cells positively correlated with total IgE in the blood. Our data indicated that circulating CXCR5 + CD4 + T cells may have a significant role in facilitating IgE production in allergic asthma patients. Copyright © 2018 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

The Tolerance and Accumulation of Miscanthus Sacchariflorus (maxim.) Benth., an Energy Plant Species, to Cadmium.

Science.gov (United States)

Zhang, Jie; Yang, Shiyong; Huang, Yongjie; Zhou, Shoubiao

2015-01-01

Miscanthus sacchariflorus (Maxim.) Benth. is a metallophyte suitable for the phytoremediation of mine wastes. The tolerance and accumulation of M. sacchariflorus to cadmium was studied by pot experiments. The results showed that O2·- generation rate, plasma membrane permeability and MDA content of M. sacchariflorus leaves increased with increasing Cd concentrations in soil, but significant effect was only observed when Cd concentrations were ≥50 mg·kg(-1). SOD and POD activities increased initially but decreased later on, whereas CAT activity only increased significantly at higher Cd concentrations, 50-100 mg·kg(-1). The content of photosynthetic pigment and growth of M. sacchariflorus were both not significantly affected when Cd concentration was ≤25 mg·kg(-1). In contrast, both parameters were significantly affected when Cd concentration was ≥50 mg·kg(-1). M. sacchariflorus could accumulate much Cd, but most of the Cd assimilated was retained in the belowground part, suggesting that M. sacchariflorus has poor ability to translocate Cd to the aboveground part. Our results suggested that although M. sacchariflorus was not a hyper-accumulator, it has a strong capacity to tolerate and stabilize the Cd. Therefore, M. sacchariflorus has a certain potential in the phytostabilization of Cd-contaminated soils.

Genotypic-dependent effects of N fertilizer, glutathione, silicon, zinc, and selenium on proteomic profiles, amino acid contents, and quality of rice genotypes with contrasting grain Cd accumulation.

Science.gov (United States)

Cao, Fangbin; Fu, Manman; Wang, Runfeng; Cheng, Wangda; Zhang, Guoping; Wu, Feibo

2017-07-01

Soil heavy metal (HM) contamination has posed a serious problem for safe food production. For restricting the translocation of HM into grain, many proteins were regulated to involve in the process. To identify these proteins, 2D-based proteomic analysis was carried out using different rice genotypes with distinct Cd accumulation in grains and as affected by an alleviating regulator (AR) in field experiments. AR application improved grain quality, with increased contents in Glu, Cys, His, Pro, and protein. Twenty-six low-grain HM accumulation-associated protein species were identified and categorized as physiological functions via two-dimensional gel electrophoresis (2DE) and mass spectrometry. Among these proteins, 8, 9, and 9 proteins exhibited higher accumulation, lower accumulation, and unchanged accumulation, respectively, in Xiushui817 (low accumulator) vs R8097 (high accumulator) under control conditions but showed differential accumulation patterns after AR application. These proteins included sucrose synthase 3, alanine aminotransferase, glutelin, cupin family protein, and zinc finger CCCH domain-containing protein 32. The differential expression of these protein species might contribute to decreased HM accumulation in grain via decreasing the protein accumulation which had high affinity to HM or regulating energy metabolism and signal transduction. Our findings provide valuable insights into the mechanisms of low-grain HM accumulation in rice and possible utilization of candidate protein species in developing low-grain HM accumulation genotypes.

Interference of Cd2+ in functioning of the photosynthetic apparatus of higher plants

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Tadeusz Baszyński

2014-01-01

Full Text Available The actual opinions concerning the role of Cd2+ in inhibition of photosynthesis have been reviewed. The light phase of photosynthesis, particularly the site of Cd2+ action in the photosynthetic transport chain has been given the greatest attention. Cd2+-induced inhibition of Photosystem II activity as the result of thylakoid membrane degradation has been discussed. The present studies on Cd2+-inhibited dark reactions occurring in stroma has been analysed. Attention has been drawn to the fact that the results of studies in vitro are not always compatible with the changes found in the photosynthetic apparatus of higher plants growing in a Cd2 containing medium.

Seasonal changes of metal accumulation and distribution in common club rush (Schoenoplectus lacustris) and common reed (Phragmites australis).

Science.gov (United States)

Duman, Fatih; Cicek, Mehmet; Sezen, Goksal

2007-08-01

In this study, two aquatic macrophytes Phragmites australis and Schoenoplectus lacustris and corresponding sediment samples were collected every three months from Lake Sapanca (Turkey) and analysed for their heavy-metal contents (Pb, Cr, Cu, Mn, Ni, Zn and Cd). Accumulation factor ratios of plant parts were calculated for all metals, and the two species were compared in terms of accumulation properties. The highest concentrations were measured in the root systems while relatively low concentrations were found in the rhizome and above-ground parts of the plants. The accumulation ratios of root for P. australis were usually higher than the ratios for S. lacustris. While the accumulation ratios of root were higher in winter than in the other seasons for P. australis, for S. lacustris the highest accumulation ratios were found in the autumn. Both plant species were found to be root accumulators of Pb, Cu, Mn, Ni, Zn and Cd.

Th1 differentiation drives the accumulation of intravascular, non-protective CD4 T cells during tuberculosis

Science.gov (United States)

Sallin, Michelle A.; Sakai, Shunsuke; Kauffman, Keith D.; Young, Howard A.; Zhu, Jinfang; Barber, Daniel L.

2017-01-01

SUMMARY Recent data indicate that the differentiation state of Th1 cells determines their protective capacity against tuberculosis. Therefore, we examined the role of Th1 polarizing factors in the generation of protective and non-protective subsets of Mtb-specific Th1 cells. We find IL-12/23p40 promotes Th1 cell expansion and maturation beyond the CD73+CXCR3+T-betdim stage, and T-bet prevents deviation of Th1 cells into Th17 cells. Nevertheless, IL-12/23p40 and T-bet are also essential for the production of a prominent subset of intravascular CX3CR1+KLRG1+ Th1 cells that persists poorly and can neither migrate into the lung parenchyma nor control Mtb growth. Furthermore, T-bet suppresses development of CD69+CD103+ tissue resident phenotype effectors in lung. In contrast, Th1 cell-derived IFNγ inhibits the accumulation of intravascular CX3CR1+KLRG1+ Th1 cells. Thus, although IL-12 and T-bet are essential host survival factors, they simultaneously oppose lung CD4 T cell responses at several levels, demonstrating the dual nature of Th1 polarization in tuberculosis. PMID:28355562

Enhanced Cadmium (Cd Phytoextraction from Contaminated Soil using Cd-Resistant Bacterium

Directory of Open Access Journals (Sweden)

Kunchaya Setkit

2014-01-01

Full Text Available A cadmium (Cd-resistant bacterium, Micrococcus sp. MU1, is able to produce indole-3-acetic acid and promotes root elongation and plant growth. The potential of this bacterium on enhancement of Cd uptake and bioaccumulation of Cd in Helianthus annuus L. planted in Cd-contaminated soil was evaluated in greenhouse condition. The results showed that Micrococcus sp. MU1promoted the growth of H. annuus L. by increasing the root length, stem height, dry biomass, root to shoot ratio and also significantly increased Cd accumulation in the root and above-ground tissues of H. annuus L. compared to uninoculated control. Re-inoculation with Micrococcus sp. MU1in contaminated soil helped in promoting plant growth and Cd phytoextraction throughout the cultivation period. In addition, phytoextraction coefficient and translocation factor (TF of H. annuus L. inoculated with Micrococcus sp. MU1were higher than that of uninoculated control and TF continuously increased with time. Our results suggested that Micrococcus sp. MU1 has an ability to enhance plant growth and Cd uptake in H. annuus L. Synergistic interaction between Micrococcus sp. MU1 and H. annuus L. could be further applied for Cd phytoextraction in polluted areas.

CD147-mediated chemotaxis of CD4+CD161+ T cells may contribute to local inflammation in rheumatoid arthritis.

Science.gov (United States)

Lv, Minghua; Miao, Jinlin; Zhao, Peng; Luo, Xing; Han, Qing; Wu, Zhenbiao; Zhang, Kui; Zhu, Ping

2018-01-01

CD161 is used as a surrogate marker for Th17 cells, which are implicated in the pathogenesis of rheumatoid arthritis (RA). In this study, we evaluated the percentage, clinical significance, and CD98 and CD147 expression of CD4 + CD161 + T cells. The potential role of CD147 and CD98 in cyclophilin A-induced chemotaxis of CD4 + CD161 + T cells was analyzed. Thirty-seven RA patients, 15 paired synovial fluid (SF) of RA, and 22 healthy controls were recruited. The cell populations and surface expression of CD98 and CD147 were analyzed by flow cytometry. Spearman's rank correlation coefficient and multiple linear regression were applied to calculate the correlations. Chemotaxis assay was used to investigate CD4 + CD161 + T cell migration. We found that the percentage of CD4 + CD161 + T cells and their expression of CD147 and CD98 in SF were higher than in the peripheral blood of RA patients. Percentage of SF CD4 + CD161 + T cells was positively correlated with 28-Joint Disease Activity Score (DAS28). CD147 monoclonal antibody (HAb18) attenuated the chemotactic ability of CD4 + CD161 + T cells. An increased CD4 + CD161 + T cell percentage and expression of CD147 and CD98 were shown in RA SF. Percentage of SF CD4 + CD161 + T cells can be used as a predictive marker of disease activity in RA. CD147 block significantly decreased the chemotactic index of CD4 + CD161 + cells induced by cyclophilin A (CypA). These results imply that the accumulation of CD4 + CD161 + T cells in SF and their high expression of CD147 may be associated with CypA-mediated chemotaxis and contribute to local inflammation in RA.

Excessive sulfur supply reduces cadmium accumulation in brown rice (Oryza sativa L.)

International Nuclear Information System (INIS)

Fan Jianling; Hu Zhengyi; Ziadi, Noura; Xia Xu; Wu Congyanghui

2010-01-01

Human activities have resulted in cadmium (Cd) and sulfur (S) accumulation in paddy soils in parts of southern China. A combined soil-sand pot experiment was conducted to investigate the influence of excessive S supply on iron plaque formation and Cd accumulation in rice plants, using two Cd levels (0, 1.5 mg kg -1 ) combined with three S concentrations (0, 60, 120 mg kg -1 ). The results showed that excessive S supply significantly decreased Cd accumulation in brown rice due to the decrease of Cd availability and the increase of glutathione in rice leaves. But excessive S supply obviously increased Cd accumulation in roots due to the decrease of iron plaque formation on the root surface of rice. Therefore, excessive S supply may result in loss of rice yield, but it could effectively reduce Cd accumulation in brown rice exposed to Cd contaminated soils. - Excessive sulfur reduces cadmium accumulation in brown rice.

Low uptake affinity cultivars with biochar to tackle Cd-tainted rice — A field study over four rice seasons in Hunan, China

International Nuclear Information System (INIS)

Chen, De; Guo, Hu; Li, Ruiyue; Li, Lianqing; Pan, Genxing; Chang, Andrew; Joseph, Stephen

2016-01-01

Biochar is becoming an environmentally friendly material for remediation of heavy metal contaminated soils and improving food safety. A field trial over four rice seasons was conducted to investigate the use of biochar and low Cd accumulating cultivars on Cd uptake in a heavy metal contaminated soil. Wheat straw derived biochar was applied at 0, 20 and 40 t ha"−"1. Two rice cultivars with differing Cd accumulation abilities were selected in each season. The results showed that both biochar and low Cd affinity cultivars significantly reduced rice grain Cd accumulation. Biochar had no significant effect the first season but thereafter consistently reduced rice grain Cd by a maximum of 61, 86 and 57% over the next three seasons. Zn accumulation in the rice grains was not decreased by biochar application, although available soil Zn was sharply reduced (35–91%). Indica conventional rice cultivars had much lower Cd, but higher Zn and lower Cd/Zn ratios in the grain than indica hybrid cultivars. Biochar was more effective for mitigating grain Cd accumulation in low Cd affinity cultivars than in high affinity cultivars. Soil pH was sustainably increased (up to nearly 1 unit) while available Cd significantly decreased by a maximum of 85% after biochar addition. The translocation of Cd from rice roots to shoots was reduced from 20 to 80% by biochar. Low uptake affinity cultivars combined with biochar reduced late rice grain Cd concentration and Cd/Zn ratios by 69–80% and 72–80%, respectively. It indicated that the management of combining biochar and low Cd affinity cultivars should be an efficient way to remediate Cd contaminated rice paddies and reduce health risk associated with consuming rice from these soils. - Highlights: • Biochar sustainably reduced soil Cd availability and Cd translocation in rice plant. • Indica conventional cultivars had lower Cd but higher Zn in grains than hybrid ones. • Biochar significantly reduced grain Cd and Cd/Zn ratio, though

Cadmium accumulation and tolerance of Macleaya cordata: a newly potential plant for sustainable phytoremediation in Cd-contaminated soil.

Science.gov (United States)

Nie, Jian; Liu, Yunguo; Zeng, Guangming; Zheng, Bohong; Tan, Xiaofei; Liu, Huan; Xie, Jieli; Gan, Chao; Liu, Wei

2016-05-01

Heavy metal pollution is a major concern of the public due to their threats to the safety of food chains. A 60-day pot experiment was conducted using Macleaya cordata as plant material to investigate the phytoremediation potential and anti-oxidative responses of M. cordata under different Cd stress. Significant growth inhibition phenomenon and toxic symptoms were not detected in the experiment. The high biomass of the plant provided high accumulation capacity for Cd with an average dry weight of 3.6 g. The maximum extraction amount of Cd was 393 μg·plant(-1), suggesting that this species had potential for phytoremediation of Cd-contaminated soil. A slight increase of chlorophyll (CHL) content was observed in Cd10 treatment. The plant was confirmed to have relatively high tolerance to the Cd stress on the basis of tolerance indexes (TI), relative water content, and CHLa/CHLb ratio. M. cordata could maintain high level of superoxide dismutase (SOD) activity under Cd stress, indicating strong tolerance capacity for reactive oxygen species (ROS) in plant cells. Catalase (CAT) activity show a certain range of decline in the experiment compare to the control. And peroxidase (POD) activity in leaves changed irregularly when compared to the control. The malondialdehyde (MDA) content increased as Cd concentration elevated compared to the control. In addition, as an inedible crop with relatively high economic value, M. cordata have shown the advantage of high biomass and high tolerance under Cd stress, which can provide a new plant resource for sustainable phytoremediation.

The Effect of Exposure to Cd and Pb in the Form of a Drinking Water or Feed on the Accumulation and Distribution of These Metals in the Organs of Growing Wistar Rats.

Science.gov (United States)

Winiarska-Mieczan, Anna; Kwiecień, Małgorzata

2016-02-01

The degree of accumulation and distribution of Cd and Pb in the organs of young animals compared to the amount taken in with water or feed have not been thoroughly investigated yet. The experiment aimed to verify whether the source of toxic metals (feed, drinking water) administered to growing rats orally has an influence on the degree of accumulation of Cd and Pb in the organs (brain, spleen, lungs, heart, liver and kidneys). The rats received Cd and/or Pb respectively in the amount of 7 mg and/or 50 mg per 1 kg of feed or per 1 L of distilled water. The rats' organs accumulated in total about 0.5 % Cd and about 0.71 % Pb consumed with water and about 0.46 % Cd and about 0.63 % Pb taken in with feed. More than 60 % of Cd and more than 70 % of Pb absorbed by the studied organs was accumulated in the liver, and more than 30 % of Cd and 26-29 % of Pb in the kidneys and less than 1 % in other organs. The relationship between the distribution percentage of Cd in the studied organs can be presented as: liver > kidneys > brain > lungs > heart > spleen. The relationship between the distribution percentage of Pb can be presented as: liver > kidneys > brain > spleen > heart > lungs. Significantly (P water.

Cadmium accumulation by jack-bean and sorghum in hydroponic culture.

Science.gov (United States)

Francato Zancheta, Ariana Carramaschi; De Abreu, Cleide Aparecida; Zambrosi, Fernando César Bachiega; de Magalhães Erismann, Norma; Andrade Lagôa, Ana Maria Magalhães

2015-01-01

Among the technologies used to recuperate cadmium (Cd) contaminated soils, phytoextraction are particularly important, where the selection of suitable plants is critical to the success of the soil remediation. Thus, the objectives of this study were to evaluate the responses of jack-bean and sorghum to Cd supply and to quantify Cd accumulation by these species grown in hydroponic culture. The plants were subjected to 0, 15, 30, or 60 μmol Cd L(-1) in the nutrient solution, and gas exchange, plant growth and Cd accumulation were measured at 25 days after starting Cd treatments. The Cd supply severely reduced growth of shoots and roots in both species. In jack-bean, Cd decreased photosynthesis by 56-86%, stomatal conductance by 59-85% and transpiration by 48-80%. The concentrations and amounts of Cd accumulated in the plant tissues were proportional to the metal supply in the nutrient solution. Sorghum was more tolerant than jack-bean to Cd toxicity, but the latter showed a greater metal concentration and accumulation in the shoot. Therefore, jack-bean would be more suitable than sorghum for use in Cd phytoremediation programs based on phytoextraction.

Differential requirements of CD4(+) T-cell signals for effector cytotoxic T-lymphocyte (CTL) priming and functional memory CTL development at higher CD8(+) T-cell precursor frequency.

Science.gov (United States)

Umeshappa, Channakeshava S; Nanjundappa, Roopa H; Xie, Yufeng; Freywald, Andrew; Xu, Qingyong; Xiang, Jim

2013-04-01

Increased CD8(+) T-cell precursor frequency (PF) precludes the requirement of CD4(+) helper T (Th) cells for primary CD8(+) cytotoxic T-lymphocyte (CTL) responses. However, the key questions of whether unhelped CTLs generated at higher PF are functional effectors, and whether unhelped CTLs can differentiate into functional memory cells at higher PF are unclear. In this study, ovalbumin (OVA) -pulsed dendritic cells (DC(OVA)) derived from C57BL/6, CD40 knockout (CD40(-/-)) or CD40 ligand knockout (CD40L(-/-)) mice were used to immunize C57BL/6, Ia(b-/-), CD40(-/-) or CD40L(-/-) mice, whose PF was previously increased with transfer of 1 × 10(6) CD8(+) T cells derived from OVA-specific T-cell receptor (TCR) transgenic OTI, OTI(CD40(-/-)) or OTI(CD40L(-/-)) mice. All the immunized mice were then assessed for effector and memory CTL responses. Following DC immunization, relatively comparable CTL priming occurred without CD4(+) T-cell help and Th-provided CD40/CD40L signalling. In addition, the unhelped CTLs were functional effectors capable of inducing therapeutic immunity against established OVA-expressing tumours. In contrast, the functional memory development of CTLs was severely impaired in the absence of CD4(+) T-cell help and CD40/CD40L signalling. Finally, unhelped memory CTLs failed to protect mice against lethal tumour challenge. Taken together, these results demonstrate that CD4(+) T-cell help at higher PF, is not required for effector CTL priming, but is required for functional memory CTL development against cancer. Our data may impact the development of novel preventive and therapeutic approaches in cancer patients with compromised CD4(+) T-cell functions. © 2012 Blackwell Publishing Ltd.

Accumulation and tolerance characteristics of cadmium in a potential hyperaccumulator-Lonicera japonica Thunb

Energy Technology Data Exchange (ETDEWEB)

Liu Zhouli [Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenhe District, Shenyang 110016 (China); Graduate School, Chinese Academy of Sciences, Jia 19 Yuquan Road, Beijing 100039 (China); He Xingyuan, E-mail: hexy@iae.ac.cn [Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenhe District, Shenyang 110016 (China); Chen Wei; Yuan Fenghui [Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenhe District, Shenyang 110016 (China); Yan Kun [Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenhe District, Shenyang 110016 (China); Graduate School, Chinese Academy of Sciences, Jia 19 Yuquan Road, Beijing 100039 (China); Tao Dali [Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenhe District, Shenyang 110016 (China)

2009-09-30

Phytoremediation using hyperaccumulators is a promising technique of removing soil pollutants. In the study, growth responses, cadmium (Cd) accumulation capability and physiological mechanisms of Lonicera japonica Thunb. under Cd stress were investigated. Exposed to 5 and 10 mg L{sup -1} Cd, the plants did not show any visual symptoms, furthermore, the height, dry biomass of leaves, roots and total and the chlorophyll (CHL) content were obtained different grade increase. When the concentration of Cd was up to 50 mg L{sup -1}, the height, dry biomass of leaves and roots had not significant differences compared with the control. The indexes of tolerance (IT) were all above 0.8. The maintenance of high superoxide dismutase (SOD) and catalase (CAT) activities was observed along with the increased Cd concentration, suggesting strong internal detoxification mechanisms inside plant cells. After 21 days exposure to 25 mg L{sup -1} Cd, stem and shoot Cd concentrations reached 344.49 {+-} 0.71 and 286.12 {+-} 9.38 {mu}g g{sup -1} DW, respectively and the plant had higher bioaccumulation coefficient (BC) and translocation factor (TF). According to these results, it was shown L. japonica had strong tolerance and accumulation capability to Cd, therefore it is a potential Cd-hyperaccumulator.

Excessive sulfur supply reduces cadmium accumulation in brown rice (Oryza sativa L.).

Science.gov (United States)

Fan, Jian-Ling; Hu, Zheng-Yi; Ziadi, Noura; Xia, Xu; Wu, Cong-Yang-Hui

2010-02-01

Human activities have resulted in cadmium (Cd) and sulfur (S) accumulation in paddy soils in parts of southern China. A combined soil-sand pot experiment was conducted to investigate the influence of excessive S supply on iron plaque formation and Cd accumulation in rice plants, using two Cd levels (0, 1.5 mg kg(-1)) combined with three S concentrations (0, 60, 120 mg kg(-1)). The results showed that excessive S supply significantly decreased Cd accumulation in brown rice due to the decrease of Cd availability and the increase of glutathione in rice leaves. But excessive S supply obviously increased Cd accumulation in roots due to the decrease of iron plaque formation on the root surface of rice. Therefore, excessive S supply may result in loss of rice yield, but it could effectively reduce Cd accumulation in brown rice exposed to Cd contaminated soils. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Low uptake affinity cultivars with biochar to tackle Cd-tainted rice — A field study over four rice seasons in Hunan, China

Energy Technology Data Exchange (ETDEWEB)

Chen, De; Guo, Hu; Li, Ruiyue [Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing 210095 (China); Li, Lianqing, E-mail: lqli@njau.edu.cn [Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing 210095 (China); Pan, Genxing [Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing 210095 (China); Chang, Andrew [Department of Environmental Sciences, University of California, Riverside, CA 92521 (United States); Joseph, Stephen [Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing 210095 (China); School of Materials Science and Engineering, University of New South Wales, Sydney, NSW 2052 (Australia)

2016-01-15

Biochar is becoming an environmentally friendly material for remediation of heavy metal contaminated soils and improving food safety. A field trial over four rice seasons was conducted to investigate the use of biochar and low Cd accumulating cultivars on Cd uptake in a heavy metal contaminated soil. Wheat straw derived biochar was applied at 0, 20 and 40 t ha{sup −1}. Two rice cultivars with differing Cd accumulation abilities were selected in each season. The results showed that both biochar and low Cd affinity cultivars significantly reduced rice grain Cd accumulation. Biochar had no significant effect the first season but thereafter consistently reduced rice grain Cd by a maximum of 61, 86 and 57% over the next three seasons. Zn accumulation in the rice grains was not decreased by biochar application, although available soil Zn was sharply reduced (35–91%). Indica conventional rice cultivars had much lower Cd, but higher Zn and lower Cd/Zn ratios in the grain than indica hybrid cultivars. Biochar was more effective for mitigating grain Cd accumulation in low Cd affinity cultivars than in high affinity cultivars. Soil pH was sustainably increased (up to nearly 1 unit) while available Cd significantly decreased by a maximum of 85% after biochar addition. The translocation of Cd from rice roots to shoots was reduced from 20 to 80% by biochar. Low uptake affinity cultivars combined with biochar reduced late rice grain Cd concentration and Cd/Zn ratios by 69–80% and 72–80%, respectively. It indicated that the management of combining biochar and low Cd affinity cultivars should be an efficient way to remediate Cd contaminated rice paddies and reduce health risk associated with consuming rice from these soils. - Highlights: • Biochar sustainably reduced soil Cd availability and Cd translocation in rice plant. • Indica conventional cultivars had lower Cd but higher Zn in grains than hybrid ones. • Biochar significantly reduced grain Cd and Cd/Zn ratio

Th1 Differentiation Drives the Accumulation of Intravascular, Non-protective CD4 T Cells during Tuberculosis.

Science.gov (United States)

Sallin, Michelle A; Sakai, Shunsuke; Kauffman, Keith D; Young, Howard A; Zhu, Jinfang; Barber, Daniel L

2017-03-28

Recent data indicate that the differentiation state of Th1 cells determines their protective capacity against tuberculosis. Therefore, we examined the role of Th1-polarizing factors in the generation of protective and non-protective subsets of Mtb-specific Th1 cells. We find that IL-12/23p40 promotes Th1 cell expansion and maturation beyond the CD73 + CXCR3 + T-bet dim stage, and T-bet prevents deviation of Th1 cells into Th17 cells. Nevertheless, IL- 12/23p40 and T-bet are also essential for the production of a prominent subset of intravascular CX3CR1 + KLRG1 + Th1 cells that persists poorly and can neither migrate into the lung parenchyma nor control Mtb growth. Furthermore, T-bet suppresses development of CD69 + CD103 + tissue resident phenotype effectors in lung. In contrast, Th1-cell-derived IFN-γ inhibits the accumulation of intravascular CX3CR1 + KLRG1 + Th1 cells. Thus, although IL-12 and T-bet are essential host survival factors, they simultaneously oppose lung CD4 T cell responses at several levels, demonstrating the dual nature of Th1 polarization in tuberculosis. Published by Elsevier Inc.

Th1 Differentiation Drives the Accumulation of Intravascular, Non-protective CD4 T Cells during Tuberculosis

Directory of Open Access Journals (Sweden)

Michelle A. Sallin

2017-03-01

Full Text Available Recent data indicate that the differentiation state of Th1 cells determines their protective capacity against tuberculosis. Therefore, we examined the role of Th1-polarizing factors in the generation of protective and non-protective subsets of Mtb-specific Th1 cells. We find that IL-12/23p40 promotes Th1 cell expansion and maturation beyond the CD73+CXCR3+T-betdim stage, and T-bet prevents deviation of Th1 cells into Th17 cells. Nevertheless, IL- 12/23p40 and T-bet are also essential for the production of a prominent subset of intravascular CX3CR1+KLRG1+ Th1 cells that persists poorly and can neither migrate into the lung parenchyma nor control Mtb growth. Furthermore, T-bet suppresses development of CD69+CD103+ tissue resident phenotype effectors in lung. In contrast, Th1-cell-derived IFN-γ inhibits the accumulation of intravascular CX3CR1+KLRG1+ Th1 cells. Thus, although IL-12 and T-bet are essential host survival factors, they simultaneously oppose lung CD4 T cell responses at several levels, demonstrating the dual nature of Th1 polarization in tuberculosis.

Accumulation and effects of metal mixtures in two seaweed species.

Science.gov (United States)

Jarvis, Tayler A; Bielmyer-Fraser, Gretchen K

2015-05-01

Metal pollution, due to various anthropogenic sources, may pose a threat to marine ecosystems. Metals can be introduced into food chains via bioaccumulation in primary producers, and may potentially lead to toxic effects. Macroalgae are used as food by a wide variety of organisms, and are therefore extremely important in aquatic systems. This study investigated the accumulation and effects of metals in two macroalgae species. The green seaweed, Ulva lactuca and the red seaweed, Agardhiella subulata were each concurrently exposed to five metals (Cu, Ni, Pb, Cd, and Zn) and U. lactuca was also exposed to each metal individually for 48 h. Metal accumulation in the seaweed was measured, and various photosynthetic parameters were assessed, using imaging pulse amplitude modulated (PAM) fluorometry. Increased metal accumulation occurred in both seaweed species after 48 h exposure to metal mixtures and each metal individually. The distribution of metals in both seaweed species changed with increasing metal exposure concentrations, resulting in higher proportions of Cu and Zn in the metal-exposed groups, as compared to respective controls. Further, U. lactuca accumulated higher concentrations of metals when exposed to each metal individually rather than in metal mixtures, suggesting interactions among metals for uptake and/or bioaccumulation. Significant impairment of photosynthetic parameters in U. lactuca was observed after exposure to 100 and 1000 μg/L metal mixtures, as well as 100 μg/L of either Cd or Cu. These results demonstrate metal bioaccumulation and toxic effects in important primary producers, and may have implications for higher trophic levels. Published by Elsevier Inc.

A newly found cadmium accumulator-Malva sinensis Cavan

International Nuclear Information System (INIS)

Zhang Shirong; Chen Mingying; Li Ting; Xu Xiaoxun; Deng Liangji

2010-01-01

Screening hyperaccumulators and accumulators is a key step in the phytoremediation of soils contaminated by heavy metals. A pot experiment was conducted involving a soil Cd concentration gradient (0, 50, 75, 100, 125, 150, 175, and 200 mg kg -1 ) to determine if Malva sinensis Cavan. from two lead-zinc mines in Kangding and Yajiang in western Sichuan, China, is a Cd-hyperaccumulator. The highest Cd concentrations in plant shoots from Kangding and Yajiang were 154.30 and 122.77 mg kg -1 , respectively, at a soil Cd concentration of 200 mg kg -1 . The largest amounts of accumulation in plant shoots from Kangding and Yajiang were 700.5 and 1403.2 μg pot -1 , respectively. The bioconcentration factors in shoots were 0.53-1.03 for Kangding and 0.69-1.25 for Yajiang. Moreover, all translocation factors of plants from the two sites were over 1.0. Therefore, M. sinensis can be classified as a Cd-accumulator or non-standard Cd-hyperaccumulator.

The uptake and accumulation of phosphorous and nitrates and the activity of nitrate reductase in cucumber seedlings treated with PbCl2 or CdCl2

Directory of Open Access Journals (Sweden)

Marek Burzyński

2014-01-01

Full Text Available Treatment of 4-day-old cucumber (Cucumis sativus L. seedlings with PbCl2 or CdCl2 caused a significant increase in the accumulation of heavy metals by the plants, especially in the roots. The accumulated Pb initially enhanced the uptake of phosphorous after the plants had been transferred to a nutrient medium (6, 24 hrs, but after only 48 Ins the uptake had dropped to below control level. The plants treated with Cd exhibited a constant decreased phosphorous uptake level. The accumulated lead and cadmium also inhibited nitrate uptake and the activity of nitrate reductase. It is suggested that the reason for the decreased nitrate reductase activity lay rather in the lower nitrate uptake than in a direct effect of the heavy metals on the enzyme.

Expression of TpNRAMP5, a metal transporter from Polish wheat (Triticum polonicum L.), enhances the accumulation of Cd, Co and Mn in transgenic Arabidopsis plants.

Science.gov (United States)

Peng, Fan; Wang, Chao; Zhu, Jianshu; Zeng, Jian; Kang, Houyang; Fan, Xing; Sha, Lina; Zhang, Haiqin; Zhou, Yonghong; Wang, Yi

2018-06-01

TpRNAMP5 is mainly expressed in the plasma membrane of roots and basal stems. It functions as a metal transporter for Cd, Mn and Co accumulation. Numerous natural resistance-associated macrophage proteins (NRAMPs) have been functionally identified in various plant species, including Arabidopsis, rice, soybean and tobacco, but no information is available on NRAMP genes in wheat. In this study, we isolated a TpNRAMP5 from dwarf Polish wheat (DPW, Triticum polonicum L.), a species with high tolerance to Cd and Zn. Expression pattern analysis revealed that TpNRAMP5 is mainly expressed in roots and basal stems of DPW. TpNRAMP5 was localized at the plasma membrane of Arabidopsis leaf protoplast. Expression of TpNRAMP5 in yeast significantly increased yeast sensitivity to Cd and Co, but not Zn, and enhanced Cd and Co concentrations. Expression of TpNRAMP5 in Arabidopsis significantly increased Cd, Co and Mn concentrations in roots, shoots and whole plants, but had no effect on Fe and Zn concentrations. These results indicate that TpNRAMP5 is a metal transporter enhancing the accumulation of Cd, Co and Mn, but not Zn and Fe. Genetic manipulation of TpNRAMP5 can be applied in the future to limit the transfer of Cd from soil to wheat grains, thereby protecting human health.

Cadmium stress in wheat seedlings: growth, cadmium accumulation and photosynthesis

DEFF Research Database (Denmark)

Ci, Dunwei; Jiang, Dong; Wollenweber, Bernd

2010-01-01

parameters were generally depressed by Cd stress, especially under the high Cd concentrations. Cd concentration and accumulation in both shoots and roots increased with increasing external Cd concentrations. Relationships between corrected parameters of growth, photosynthesis and fluorescence and corrected......Seedlings of wheat (Triticum aestivum L.) cultivars Jing 411, Jinmai 30 and Yangmai 10 were exposed to 0, 10, 20, 30, 40 or 50 μM of CdCl2 in a solution culture experiment. The effects of cadmium (Cd) stress on wheat growth, leaf photon energy conversion, gas exchange, and Cd accumulation in wheat...

Root morphological responses of three hot pepper cultivars to Cd exposure and their correlations with Cd accumulation.

Science.gov (United States)

Huang, Baifei; Xin, Junliang; Dai, Hongwen; Liu, Aiqun; Zhou, Wenjing; Yi, Yumei; Liao, Kebing

2015-01-01

Cultivars of hot pepper (Capsicum annuum L.) differ widely in their fruit cadmium (Cd) concentrations. Previously, we suggested that low-Cd cultivars are better able to prevent the translocation of Cd from roots to aboveground parts, but the corresponding mechanisms are still unknown. In this study, we aimed to improve understanding of the root morphological characteristics of the mechanisms involved in two low-Cd and a high-Cd cultivar. Seedlings were grown in nutrient solutions containing 0 (control), 2, and 10 μM Cd for 20 days, and Cd contents for the three cultivars were compared with changes in root morphology. The total root length (RL), root surface area (SA), number of root tips (RT), and specific root length (SRL) of all cultivars were decreased significantly by the 10 μM Cd treatment with the exception of the SA in JFZ, which showed no obvious change. For each cultivar, the 10 μM Cd treatment decreased significantly RL and SA specifically in roots with diameters (RD) of RD ≤ 0.2 mm or 0.2 mm roots with diameters of 0.6 mm root morphology. In the 10 μM Cd treatment, root volume (RV), SA, and RT of all cultivars were negatively correlated with Cd concentration and amount in roots. However, RL, SA, RV, and RT of all cultivars were positively correlated with Cd concentration and amount in shoots, and translocation rate of Cd. The two low-Cd cultivars of hot pepper had less root tips, shorter root length, and smaller root surface area than the high-Cd cultivar in 10 μM Cd treatment, which may play a vital role in reducing root-to-shoot Cd translocation.

Holm Oak (Quercus ilex L.) canopy as interceptor of airborne trace elements and their accumulation in the litter and topsoil

International Nuclear Information System (INIS)

Fantozzi, Federica; Monaci, Fabrizio; Blanusa, Tijana; Bargagli, Roberto

2013-01-01

We investigated the role of urban Holm Oak (Quercus ilex L.) trees as an airborne metal accumulators and metals' environmental fate. Analyses confirmed Pb, Cd, Cu and Zn as a main contaminants in Siena's urban environment; only Pb concentrations decreased significantly compared to earlier surveys. Additionally, we determined chemical composition of tree leaves, litter and topsoil (underneath/outside tree crown) in urban and extra-urban oak stands. Most notably, litter in urban samples collected outside the canopy had significantly lower concentrations of organic matter and higher concentrations of Pb, Cu, Cd and Zn than litter collected underneath the canopy. There was a greater metals' accumulation in topsoil, in samples collected under the tree canopy and especially near the trunk (‘stemflow area’). Thus, in urban ecosystems the Holm Oak stands likely increase the soil capability to bind metals. -- Highlights: ► Of the main metal contaminants only leaf Pb concentrations decreased in the period 1994–2011. ► Leaf Cd, Cr, Cu, Pb and Zn concentrations were higher in urban than in extra urban park. ► In urban park litter, Cu, Cd, Pb and Zn concentrations were higher outside than underneath the tree crown. ► Conversely, in urban park soil, Cu, Cd, Pb and Zn concentrations were lower outside the crown. ► Soil therefore behaves as a sink for metal contaminants such as Cu, Pb and Cd. -- Quercus ilex leaves are efficient interceptors of airborne trace elements in urban environments and we found an increased accumulation of metals in topsoil under the tree canopy

Model optimization of cadmium and accumulation in switchgrass (Panicum virgatum L.): potential use for ecological phytoremediation in Cd-contaminated soils.

Science.gov (United States)

Wang, Quanzhen; Gu, Muyu; Ma, Xiaomin; Zhang, Hongjuan; Wang, Yafang; Cui, Jian; Gao, Wei; Gui, Jing

2015-11-01

Soil pollution with heavy metals is an increasingly serious threat to the environment, food security, and human health. Therefore, it is urgent to develop economic and highly efficient soil restoration technology for environmental improvement; phytoremediation is an option that is safe, has low cost, and is environmentally friendly. However, in selecting hyperaccumulators or tolerant plants, theories and operation technologies for optimal restoration should be satisfied. In this study, the switchgrass growth response and performance of phytoextraction under the coupling effect of Cd and pH were investigated by evaluating seed germination, seedling growth, and the Cd content in the plant to evaluate the potential use of switchgrass as a phytoremediation plant in cadmium contaminated soil. This study conducted three sets of independent experiments with five levels of Cd concentrations, including two orthogonal matrix designs of combining Cd with pH values. The results showed that switchgrass was germinated well under all treatments (Cd concentration of 0-500 μM), but the seedling growth was significantly affected by Cd and pH, as shown by multivariate regression analyses. Hormesis was found during the growth of switchgrass plants exposed to low Cd concentrations under hydroponic conditions, and switchgrass plants were capable of developing with a Cd concentration of 100-175 μM and pH of 4.1-5.9. Mild acidic conditions can enhance the ability of Cd to accumulate in switchgrass. Switchgrass was moderately tolerant to Cd and may be used as a phytoremediation plant for Cd-contaminated soils in the future. Our results also suggest that hormetic effects should be taken into consideration in the phytoremediation of Cd-contaminated soils. We discuss the physiological and biochemical mechanisms contributing to the effective application of the plant for the phytoremediation of Cd-contaminated soils.

Assessment of macro and microelement accumulation capability of two aquatic plants

International Nuclear Information System (INIS)

Baldantoni, Daniela; Alfani, Anna; Di Tommasi, Paul; Bartoli, Giovanni; De Santo, Amalia Virzo

2004-01-01

The concentrations of four macroelements (C, N, P, S) and eight trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) were measured in the leaves and roots of the emergent plant, Phragmites communis Trin., and in the shoots and roots of the submersed Najas marina L., taken from Lake Averno (Naples, Italy). Phragmites communis leaves showed higher concentrations of carbon, nitrogen and phosphorus than roots, while the roots exhibited significantly higher concentrations of sulphur and trace metals. Najas marina roots also showed higher concentrations of sulphur and trace metals than shoots, but these differences were less marked than in Phragmites communis except for sulphur. Sulphur was the only macronutrient to show the highest concentrations in the roots. Phragmites communis roots had higher values of Cr, Cu, Fe, Mn and Ni than Najas marina roots. By contrast, Cd, Cr, Fe, Ni, Pb and Zn concentrations were higher in Najas marina shoots than in Phragmites communis leaves. Phragmites communis, available through the year, showing high capability to accumulate trace metals in the roots, appears a good monitor of lake contamination, better than Najas marina. - Element accumulation in roots and shoots of aquatic plants was used as a criteria for selecting useful biomonitors

Kinetics of cadmium accumulation and elimination in carp Cyprinus carpio tissues

International Nuclear Information System (INIS)

Conto Cinier, C. de; Petit-Ramel, M.; Faure, R.; Garin, D.; Bouvet, Y.

1999-01-01

Carp (Cyprinus carpio) were tested for cadmium accumulation and elimination during and after a simulated pollution exposure. Fish were distributed in two 1000-l indoor concrete aquaria supplied with a continuous flow (8 l min -1 ) of well water. The cadmium concentration was maintained at 53 μg l -1 in one aquarium and 443 μg l -1 in the other aquarium for 127 days. The exposure phase was followed by a 43-day depuration period. The cadmium accumulation in liver, kidney and muscle was measured by means of ICP-MS. The data showed that cadmium exposure produces significant cadmium uptake in tissues. Cadmium concentrations increased sharply in kidney and liver, whereas the pollutant level in muscle was only significant after 106 days. After 127 days of Cd exposure (53 μg l -1 ), the cadmium concentration in kidney was 4-fold higher than in liver and 50-fold higher than in muscle for a toxic level of 53 μg l -1 . At a Cd of 443 μg l -1 , kidney cadmium content was 2-fold higher than in liver and 100-fold higher than in muscle. In kidney and liver, the toxic concentration increased as the concentration of pollutant in water increased. During the 43 depuration days, the loss of accumulated cadmium was rapid and immediate in muscle. Conversely, no loss of cadmium was observed in kidney and liver. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Tissue-specific Bio-accumulation of Metals in Fish during Chronic Waterborne and Dietary Exposures

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M. Javed

2012-10-01

Full Text Available Juvenile (120-day three fish species viz. Catla catla, Labeo rohita and Cirrhina mrigala were exposed to chronic sub-lethal concentrations (1/3rd of LC50/LD50 of waterborne and dietary copper (Cu, cadmium (Cd, zinc (Zn, nickel (Ni and cobalt (Co, separately, in glass aquaria under constant water temperature (29oC, pH (7.5 and hardness (225 mgL-1 for 12 weeks. Waterborne and dietary exposures caused significantly variable accumulation of metals in three fish species that followed Zn>Ni>Cd>Co>Cu. Fish liver showed significantly higher tendency to accumulate Cu (69.64±25.35 µg g-1, Cd (68.93±21.65 µg g-1, Zn (91.46±29.53 µg g-1, Ni (74.64±18.61 µg g-1 and Co (22.65±20.56 µg g-1, followed by that of kidney and gills, with significant differences while muscle and bones exhibited significantly least tendency to accumulate all metals. Labeo rohita (31.63±2.43 µg g-1 and C. mrigala (31.43±13.70 µg g-1 exhibited significantly higher ability to amass metals than that of C. catla (27.96±10.28 µg g-1. Waterborne exposure caused significantly higher accumulation of metals in fish liver (72.69±27.91 µg g-1, followed by that in kidney, gills, skin, muscle, fins and bones with the average concentrations of 45.14±18.70, 39.47±21.13, 30.81±12.64, 22.65±17.34, 22.23±11.74 and 12.14±6.25 µg g-1, respectively. Dietary exposure resulted into significant escalation of metals in fish liver (58.23±32.44 µg g-1 while it was lowest in bones. Waterborne exposure caused significantly higher accumulation of all metals in fish body than that of dietary treatments.

Cadmium accumulation in zebrafish (Danio rerio) eggs is modulated by dissolved organic matter (DOM)

International Nuclear Information System (INIS)

Burnison, B. Kent; Meinelt, Thomas; Playle, Richard; Pietrock, Michael; Wienke, Andreas; Steinberg, Christian E.W.

2006-01-01

Experiments were conducted to investigate factors influencing the accumulation of cadmium (Cd 2+ ) into zebrafish (Danio rerio) eggs. The accumulation of 109 Cd was affected by: (1) concentration, (2) time, (3) presence of dissolved organic material (DOM), (4) different origin of DOM and (5) different parts of fish eggs. Over a 5-h exposure, zebrafish eggs showed a steady increase in Cd-accumulation. DOM-concentrations over 15 ppm carbon (C) decreased Cd-uptake significantly. Both samples of DOM, brown water marsh (LM) and a eutrophic pond (SP), at 16.9 ppm C, reduced the Cd-accumulation in the chorion, perivitelline liquid and the embryo. Cd was mainly accumulated in the egg's outer shell chorion (61%) and only small amounts passed through the chorion into the perivitelline liquid (38%) and embryo (1%). In the presence of LM-DOM, the accumulation of Cd into the egg components was decreased by 43% (chorion), 52% (perivitelline liquid) and 52% (embryo), respectively, compared with the control group. Similarly, the presence of SP-DOM reduced the Cd-accumulation by 29% (chorion), 61% (perivitelline liquid) and 60% (embryo), respectively, compared with the controls. DOM-concentration should be taken into consideration when determining ecotoxicological effects of Cd on fish populations

A newly found cadmium accumulator-Malva sinensis Cavan

Energy Technology Data Exchange (ETDEWEB)

Zhang Shirong, E-mail: rsz01@163.com [College of Resources and Environment, Sichuan Agricultural University, 46 Xinkang Road, Yaan 625014 (China); Chen Mingying; Li Ting; Xu Xiaoxun; Deng Liangji [College of Resources and Environment, Sichuan Agricultural University, 46 Xinkang Road, Yaan 625014 (China)

2010-01-15

Screening hyperaccumulators and accumulators is a key step in the phytoremediation of soils contaminated by heavy metals. A pot experiment was conducted involving a soil Cd concentration gradient (0, 50, 75, 100, 125, 150, 175, and 200 mg kg{sup -1}) to determine if Malva sinensis Cavan. from two lead-zinc mines in Kangding and Yajiang in western Sichuan, China, is a Cd-hyperaccumulator. The highest Cd concentrations in plant shoots from Kangding and Yajiang were 154.30 and 122.77 mg kg{sup -1}, respectively, at a soil Cd concentration of 200 mg kg{sup -1}. The largest amounts of accumulation in plant shoots from Kangding and Yajiang were 700.5 and 1403.2 {mu}g pot{sup -1}, respectively. The bioconcentration factors in shoots were 0.53-1.03 for Kangding and 0.69-1.25 for Yajiang. Moreover, all translocation factors of plants from the two sites were over 1.0. Therefore, M. sinensis can be classified as a Cd-accumulator or non-standard Cd-hyperaccumulator.

The potential of wild vegetation species of Eleusine indica L., and Sonchus arvensis L. for phytoremediation of Cd-contaminated soil

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Amir Hamzah

2017-04-01

Full Text Available Phytoremediation has been intensively studied due its costs effectiveness and environmentally sound. Studies of heavy metal pollution phytoremediation has been done in develop countries, but still limited in Indonesia. This study aims to explore the potential of wild plant species Eleusine indica L. and Sonchus arvensis L. as an agent of phytoremediation on Cd-contaminated soil. This study was done descriptively in Pujon, Malang, Indonesia, to test the ability of two species of wild plants E. indica and S. arvensis in absorbing Cd. Along this research, plant growth and the concentration of Cd in roots, stems and leaves, was monitored. Plant growth was measured every week for three months. The plant roots, stems, and leaves collected separately, then analyzed its Cd levels. The results showed that both of two species of wild plants grew well on soil contaminated Cd. Plant roots can accumulate higher Cd than the stem part. In addition, E indica has the ability to accumulate Cd higher than S. arvensis, i.e. 57.11% and 35.84%, respectively

Heavy metal accumulation in arctic hares (Lepus arcticus) in Nunavut, Canada

Energy Technology Data Exchange (ETDEWEB)

Pedersen, Simen [Department of Biology, University of Tromso, N-9037 Tromso (Norway)]. E-mail: simenpeders1@gmail.com; Lierhagen, Syverin [Norwegian Institute for Nature Research, Tungasletta 2, N-7485 Trondheim (Norway)

2006-09-15

Accumulation of cadmium, mercury, lead, copper and zinc was studied in muscle, liver and kidney of 9 adult and 7 juvenile arctic hares (Lepus arcticus), collected in 2003 in the southwestern part of Nunavut, Canada. Our objective was to determine the level of heavy metal accumulation, and distribution among age groups and tissue. Concentrations of all metals varied among tissues, and concentrations of Cd, Hg and Zn were higher in adults compared to juveniles. We found correlations in metal content among tissues, and among metals in kidneys. We also found the hares to have low concentration of most heavy metals except cadmium. We suggest that the high cadmium levels might be caused by the local geology, and the hares being adapted to these levels. The low levels of the other metals are probably due to low input of atmospheric contaminants. Only one of the individuals had Cd content slightly above the maximum contaminant levels recommended for human consumption of meat. There were no levels in meat above the recommended maximum for the rest of the metals surveyed. However the Cd levels in liver and kidney are orders of magnitude higher than the recommended maximum, and consumption of these organs should be avoided.

Relationship between heavy metal accumulation and morphometric parameters in European hare (Lepus europaeus) inhabiting various types of landscapes in southern Poland.

Science.gov (United States)

Wajdzik, Marek; Halecki, Wiktor; Kalarus, Konrad; Gąsiorek, Michał; Pająk, Marek

2017-11-01

To evaluate the influence of hazardous substances in the environment, studies of pollutant accumulation in wild living animals are needed. Studies dealing with heavy metal contamination in mammals usually focus on a single organ. We investigated accumulation of heavy metals as well as iron in European hare (Lepus europaeus) living in southern Poland, Małopolska Province. Hares were captured during the hunting season. We tested metal accumulation in 14 organs and tissues using 35 individuals with known body weight and sex inhabiting agricultural, industrial and other types of landscapes. To obtain deeper insight into contamination patterns, we used accumulation data from the liver since it is the most frequently investigated organ and prone to pollution accumulation. Based on the data obtained for the liver, we tested the impact of metal pollution on hare morphology, including body length and several skull cranimetric parameters. Metals content differed between organs. Moreover, individuals from industrial areas had higher Cd content in their body. We distinguished two groups of elements: the first group, Cd, Fe and Zn, revealed the highest toxic effect in the liver and kidneys; the second group, Cr, Ni, and Pb, accumulated primarily in the brain. Hares inhabiting industrial areas had higher concentration of Cd and Pb, and lower levels of Cr and Fe in their liver in comparison with those from agricultural and forest habitats. Heavy metals had an effect on body length that was negatively associated with Cr levels. Skull diastema length was associated positively with accumulation of Cd and Pb. We showed that hare organs and tissues could be used as bioindicators of environmental pollution by heavy metals. Copyright © 2017 Elsevier Inc. All rights reserved.

Free-ranging European bisons accumulate more cadmium in the liver and kidneys than domestic cattle in north-eastern Poland

International Nuclear Information System (INIS)

Wlostowski, Tadeusz; Bonda, Elzbieta; Krasowska, Alicja

2006-01-01

It has been shown that free-ranging big game animals accumulate several-fold more cadmium (Cd) in the liver and kidneys than domestic animals. To examine possible reasons for this difference, in the present work we determined the concentrations of Cd in the liver and kidney cortex of European bisons (n = 23) from Bialowieza Forest (north-eastern Poland) and domestic cattle (n = 15) from the same region; in addition, analyses of Cd in the grasses and soil as well as of soil pH were carried out. The accumulation of Cd in liver and kidney cortex of the female bisons correlated significantly with the age up to 7 years, but stabilized thereafter. The 7-12-year-old bisons had 2.14- and 2.25-fold higher concentrations of Cd in the liver and kidney cortex, respectively, than the age-matched domestic cattle. Notably, the Cd levels in the liver and kidneys of the 8-12-year-old cattle were comparable to those found in the 2-year-old and 4-6-year-old bisons, respectively. The content of Cd in the grasses from Bialowieza Forest appeared to be 2.1-fold higher than that in the plants from the pastures. Similarly, the concentration of water-extractable Cd in the soil was 2.7-fold greater in Bialowieza Forest than in the pastures, despite the fact that nitric acid-extractable Cd (total Cd) was similar in the soils from the two sites. The concentration of water-extractable Cd in the soil as well as the content of Cd in the grasses inversely correlated with soil pH, which appeared to be significantly lower in Bialowieza Forest. These data indicate that soil pH is probably responsible for the higher concentrations of Cd in the feed and tissues of bisons as compared with those of domestic cattle

Arbuscular mycorrhizal fungi enhance both absorption and stabilization of Cd by Alfred stonecrop (Sedum alfredii Hance) and perennial ryegrass (Lolium perenne L.) in a Cd-contaminated acidic soil.

Science.gov (United States)

Hu, Junli; Wu, Shengchun; Wu, Fuyong; Leung, Ho Man; Lin, Xiangui; Wong, Ming Hung

2013-10-01

A greenhouse pot experiment was conducted to compare the phytoextraction efficiencies of Cd by hyper-accumulating Alfred stonecrop (Sedum alfredii Hance) and fast-growing perennial ryegrass (Lolium perenne L.) from a Cd-contaminated (1.6 mg kg(-1)) acidic soil, and their responses to the inoculations of two arbuscular mycorrhizal (AM) fungal strains, Glomus caledonium 90036 (Gc) and Glomus mosseae M47V (Gm). Ryegrass and stonecrop were harvested after growing for 9 and 27 wk, respectively. Without AM fungal inoculation, the weekly Cd extraction by stonecrop (8.0 μg pot(-1)) was 4.3 times higher than that by ryegrass (1.5 μg pot(-1)). Both Gc and Gm significantly increased (P soil acid phosphatase activities, and available P concentrations, and thereby plant P absorptions (except for Gm-inoculated ryegrass), shoot biomasses, and Cd absorptions (except for Gm-inoculated stonecrop), while only Gc-inoculated stonecrop significantly accelerated (P soil pH. The results suggested the potential application of hyper-accumulating Alfred stonecrop associated with AM fungi (notably Gc) for both extraction and stabilization of Cd in the in situ treatment of Cd-contaminated acidic soil. Copyright © 2013 Elsevier Ltd. All rights reserved.

Accumulation and distribution of iron, cadmium, lead and nickel in cucumber plants grown in hydroponics containing two different chelated iron supplies.

Science.gov (United States)

Csog, Árpád; Mihucz, Victor G; Tatár, Eniko; Fodor, Ferenc; Virág, István; Majdik, Cornelia; Záray, Gyula

2011-07-01

Cucumber plants grown in hydroponics containing 10 μM Cd(II), Ni(II) and Pb(II), and iron supplied as Fe(III) EDTA or Fe(III) citrate in identical concentrations, were investigated by total-reflection X-ray fluorescence spectrometry with special emphasis on the determination of iron accumulation and distribution within the different plant compartments (root, stem, cotyledon and leaves). The extent of Cd, Ni and Pb accumulation and distribution were also determined. Generally, iron and heavy-metal contaminant accumulation was higher when Fe(III) citrate was used. The accumulation of nickel and lead was higher by about 20% and 100%, respectively, if the iron supply was Fe(III) citrate. The accumulation of Cd was similar. In the case of Fe(III) citrate, the total amounts of Fe taken up were similar in the control and heavy-metal-treated plants (27-31 μmol/plant). Further, the amounts of iron transported from the root towards the shoot of the control, lead- and nickel-contaminated plants were independent of the iron(III) form. Although Fe mobility could be characterized as being low, its distribution within the shoot was not significantly affected by the heavy metals investigated. Copyright © 2011 Elsevier GmbH. All rights reserved.

Investigation of Cd Uptake and Transfer in Different Parts of Wheat, Spinach, Cucumber and Carrot Crops

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Bahman Yargholi

2016-01-01

Full Text Available Environmental pollution due to the accumulation of heavy metals in soil and their subsequent transfer to crops is a global concern that arises from improper application of industrial wastewaters. This study was conducted to investigate the effects of different levels of soil Cd on its accumulation rate in the various organs of four common crops in Iran (namely, wheat, spinach, cucumber, and carrot. The experiment was performed in a factorial design with random blocks including 3 treatments with 0 (control, 50, and 100 mg/kg.soil in 4 replicates. Soil was collected from the farm belonging to the Research Institute for Plant and Seed Breeding (Karaj and filtered twice using 2-mm sieves before Cadmium Nitrate (Cd(NO32 was added and completely mixed. Crops were planted in plastic pots 40 cm in diameter and 60 cm in height. The water demand was determined using the Jenman Mantite method. At the end of the growing season, samples were taken from various organs of the crops and their Cd concentrations were measured. The results revealed a direct relationship between Cd accumulation and Cd concentration in the root region. All the treatments other than the control exhibited Cd concentrations higher than the standard limits for human consumption. Cadmium accumulation in the different organs of the crops exhibited the following orders: Root: Cucumber

Plasmacytoid dendritic cells accumulate and secrete interferon alpha in lymph nodes of HIV-1 patients.

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Clara Lehmann

2010-06-01

Full Text Available Circulating plasmacytoid dendritic cells (pDC decline during HIV-1 infection, but at the same time they express markedly higher levels of interferon alpha (IFNalpha, which is associated with HIV-1 disease progression. Here we show an accumulation of pDC in lymph nodes (LN of treatment-naïve HIV-1 patients. This phenomenon was associated with elevated expression of the LN homing marker, CCR7, on pDC in peripheral blood of HIV-1 patients, which conferred increased migratory capacity in response to CCR7 ligands in ex vivo functional assays. LN-homed pDC of HIV-1 patients presented higher CD40 and lower BDCA2 levels, but unchanged CD83 and CD86 expression. In addition, these cells expressed markedly higher amounts of IFNalpha compared to uninfected individuals, and were undergoing faster rates of cell death. These results demonstrate for the first time that in asymptomatic, untreated HIV-1 patients circulating pDC up-regulate CCR7 expression, accumulate in lymph nodes, and express high amounts of IFNalpha before undergoing cell death. Since IFNalpha inhibits cell proliferation and modulates immune responses, chronically high levels of this cytokine in LN of HIV-1 patients may impair differentiation and immune function of bystander CD4(+ T cells, thus playing into the mechanisms of AIDS immunopathogenesis.

Assessment of potential soybean cadmium excluder cultivars at different concentrations of Cd in soils.

Science.gov (United States)

Zhi, Yang; He, Kangxin; Sun, Ting; Zhu, Yongqiang; Zhou, Qixing

2015-09-01

The selection of cadmium-excluding cultivars has been used to minimize the transfer of cadmium into the human food chain. In this experiment, five Chinese soybean plants were grown in three soils with different concentrations of Cd (0.15, 0.75 and 1.12mg/kg). Variations in uptake, enrichment, and translocation of Cd among these soybean cultivars were studied. The results indicated that the concentration of Cd in seeds that grew at 1.12mg/kg Cd in soils exceeded the permitted maximum levels in soybeans. Therefore, our results indicated that even some soybean cultivars grown on soils with permitted levels of Cd might accumulate higher concentrations of Cd in seeds that are hazardous to human health. The seeds of these five cultivars were further assessed for interactions between Cd and other mineral nutrient elements such as Ca, Cu, Fe, Mg, Mn and Zn. High Cd concentration in soil was found to inhibit the uptake of Mn. Furthermore, Fe and Zn accumulations were found to be enhanced in the seeds of all of the five soybean cultivars in response to high Cd concentration. Cultivar Tiefeng 31 was found to fit the criteria for a Cd-excluding cultivar under different concentrations of Cd in soils. Copyright © 2015. Published by Elsevier B.V.

Seasonal effects of cadmium accumulation in periphytic diatom communities of freshwater biofilms

International Nuclear Information System (INIS)

Thi Thuy Duong; Morin, Soizic; Herlory, Olivier; Feurtet-Mazel, Agnes; Coste, Michel; Boudou, Alain

2008-01-01

The relationships between diatom species and cadmium (Cd) accumulated in biofilms of the Riou-Mort River (SW, France) were studied in July 2004 and March 2005. Biofilms were sampled from artificial substrates immersed along a metallic pollution gradient during 20 days. Dynamics of diatom communities and cadmium accumulation were followed by collecting samples after 4, 7, 14 and 20 days of biofilm colonization. Cd accumulation in biofilms during experiment was significantly higher in Cd polluted station (Joanis) than in reference station (Firmi) for both seasons. Periphytic diatom composition varied between sites and seasons. At Firmi station, seasonal dynamics of diatom communities were stable with the dominance of Cyclotella meneghiniana and Melosira varians in July and Surirellabrebissonnii and Navicula gregaria in March. At Joanis station, diatom communities mainly responded to high levels of metal by a high proportion of small, adnate species. Positive correlations between Eolimna minima, Nitzschia palea, Encyonema minutum, Surirella angusta, and Gomphonema parvulum and cadmium accumulation were observed, indicating that these species are tolerant to high levels of cadmium. On the other hand, negative correlations of C. meneghiniana, N. gregaria, Navicula lanceolata, M. varians and Nitzschia dissipata with cadmium qualify them as sensitive diatom species. Periphytic diatom composition through the presence of specific species highlight metal tolerant indicator diatom groups which will be meaningful for biomonitoring pollution in natural aquatic systems

Seasonal effects of cadmium accumulation in periphytic diatom communities of freshwater biofilms

Energy Technology Data Exchange (ETDEWEB)

Thi Thuy Duong [Institute of Environmental Technology, Vietnamese Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay, Hanoi (Viet Nam); Universite de Bordeaux 1, CNRS, UMR 5805 EPOC, Place du Dr Peyneau, 33120 Arcachon (France)], E-mail: duongthuy0712@yahoo.com; Morin, Soizic [Cemagref, UR REBX, 50 avenue de Verdun, F-33612 Cestas cedex (France); Herlory, Olivier [Universite de Bordeaux 1, CNRS, UMR 5805 EPOC, Place du Dr Peyneau, 33120 Arcachon (France); Feurtet-Mazel, Agnes [Universite de Bordeaux 1, CNRS, UMR 5805 EPOC, Place du Dr Peyneau, 33120 Arcachon (France)], E-mail: a.feurtet-mazel@epoc.u-bordeaux1.fr; Coste, Michel [Cemagref, UR REBX, 50 avenue de Verdun, F-33612 Cestas cedex (France); Boudou, Alain [Universite de Bordeaux 1, CNRS, UMR 5805 EPOC, Place du Dr Peyneau, 33120 Arcachon (France)

2008-10-20

The relationships between diatom species and cadmium (Cd) accumulated in biofilms of the Riou-Mort River (SW, France) were studied in July 2004 and March 2005. Biofilms were sampled from artificial substrates immersed along a metallic pollution gradient during 20 days. Dynamics of diatom communities and cadmium accumulation were followed by collecting samples after 4, 7, 14 and 20 days of biofilm colonization. Cd accumulation in biofilms during experiment was significantly higher in Cd polluted station (Joanis) than in reference station (Firmi) for both seasons. Periphytic diatom composition varied between sites and seasons. At Firmi station, seasonal dynamics of diatom communities were stable with the dominance of Cyclotella meneghiniana and Melosira varians in July and Surirellabrebissonnii and Navicula gregaria in March. At Joanis station, diatom communities mainly responded to high levels of metal by a high proportion of small, adnate species. Positive correlations between Eolimna minima, Nitzschia palea, Encyonema minutum, Surirella angusta, and Gomphonema parvulum and cadmium accumulation were observed, indicating that these species are tolerant to high levels of cadmium. On the other hand, negative correlations of C. meneghiniana, N. gregaria, Navicula lanceolata, M. varians and Nitzschia dissipata with cadmium qualify them as sensitive diatom species. Periphytic diatom composition through the presence of specific species highlight metal tolerant indicator diatom groups which will be meaningful for biomonitoring pollution in natural aquatic systems.

Heavy metal accumulation in trees growing on contaminated sites in Central Europe

International Nuclear Information System (INIS)

Unterbrunner, R.; Puschenreiter, M.; Sommer, P.; Wieshammer, G.; Tlustos, P.; Zupan, M.; Wenzel, W.W.

2007-01-01

Metal-accumulating woody species have been considered for phytoextraction of metal-contaminated sites. We investigated Zn and Cd accumulation in tissues of adult trees and associated herbaceous species collected from contaminated areas in Central Europe. We found considerable Cd and Zn accumulation in various willow, poplar and birch species with up to 116 mg Cd kg -1 and 4680 mg Zn kg -1 in leaves of Salix caprea. Annual variation of Cd and Zn concentrations in leaves of Salix caprea were small, indicating that data obtained in different years can be compared. Metal concentrations in leaves were not related to total (aqua regia) or labile (1 M NH 4 NO 3 extract) concentrations in soil but the accumulation factors (leaf concentration: soil concentration) for Cd and Zn followed an inverse log type function. Metal partitioning between tissues showed a minimum in the wood, with increasing concentrations of Cd and Zn towards the leaves and fine roots. - Adult field-grown Salix caprea, Populus tremula and other tree species accumulate up to 4680 mg Zn kg -1 and 116 mg Cd kg -1 in their leaves

Heavy metal accumulation in trees growing on contaminated sites in Central Europe

Energy Technology Data Exchange (ETDEWEB)

Unterbrunner, R. [University of Natural Resources and Applied Life Sciences, Vienna - BOKU, Department of Forest and Soil Sciences, Peter Jordan Strasse 82, A-1190 Vienna (Austria); Puschenreiter, M. [University of Natural Resources and Applied Life Sciences, Vienna - BOKU, Department of Forest and Soil Sciences, Peter Jordan Strasse 82, A-1190 Vienna (Austria)]. E-mail: markus.puschenreiter@boku.ac.at; Sommer, P. [University of Natural Resources and Applied Life Sciences, Vienna - BOKU, Department of Forest and Soil Sciences, Peter Jordan Strasse 82, A-1190 Vienna (Austria); Wieshammer, G. [University of Natural Resources and Applied Life Sciences, Vienna - BOKU, Department of Forest and Soil Sciences, Peter Jordan Strasse 82, A-1190 Vienna (Austria); Tlustos, P. [Czech University of Agriculture Prague, 165 21 Praha 6-Suchdol (Czech Republic); Zupan, M. [University of Ljubljana, Biotechnical Faculty, Agronomy department, Jamnikarjeva 101, 1000 Ljubljana (Slovenia); Wenzel, W.W. [University of Natural Resources and Applied Life Sciences, Vienna - BOKU, Department of Forest and Soil Sciences, Peter Jordan Strasse 82, A-1190 Vienna (Austria)

2007-07-15

Metal-accumulating woody species have been considered for phytoextraction of metal-contaminated sites. We investigated Zn and Cd accumulation in tissues of adult trees and associated herbaceous species collected from contaminated areas in Central Europe. We found considerable Cd and Zn accumulation in various willow, poplar and birch species with up to 116 mg Cd kg{sup -1} and 4680 mg Zn kg{sup -1} in leaves of Salix caprea. Annual variation of Cd and Zn concentrations in leaves of Salix caprea were small, indicating that data obtained in different years can be compared. Metal concentrations in leaves were not related to total (aqua regia) or labile (1 M NH{sub 4}NO{sub 3} extract) concentrations in soil but the accumulation factors (leaf concentration: soil concentration) for Cd and Zn followed an inverse log type function. Metal partitioning between tissues showed a minimum in the wood, with increasing concentrations of Cd and Zn towards the leaves and fine roots. - Adult field-grown Salix caprea, Populus tremula and other tree species accumulate up to 4680 mg Zn kg{sup -1} and 116 mg Cd kg{sup -1} in their leaves.

Anergic CD4+ T cells form mature immunological synapses with enhanced accumulation of c-Cbl and Cbl-b1

Science.gov (United States)

Doherty, Melissa; Osborne, Douglas G.; Browning, Diana L.; Parker, David C.; Wetzel, Scott A.

2010-01-01

CD4+ T cell recognition of MHC:peptide complexes in the context of a costimulatory signal results in the large-scale redistribution of molecules at the T-APC interface to form the immunological synapse. The immunological synapse is the location of sustained TCR signaling and delivery of a subset of effector functions. T cells activated in the absence of costimulation are rendered anergic and are hyporesponsive when presented with antigen in the presence of optimal costimulation. Several previous studies have looked at aspects of immunological synapses formed by anergic T cells, but it remains unclear whether there are differences in the formation or composition of anergic immunological synapses. In this study we anergized primary murine CD4+ T cells by incubation of costimulation-deficient, transfected fibroblast APC. Using a combination of TCR, MHC:peptide, and ICAM-1 staining, we found that anergic T cells make mature immunological synapses with characteristic cSMAC and pSMAC domains that were indistinguishable from control synapses. There were small increases in total phosphotyrosine at the anergic synapse along with significant decreases in phosphorylated ERK 1/2 accumulation. Most striking, there was specific accumulation of c-Cbl and Cbl-b to the anergic synapses. Cbl-b, previously shown to be essential in anergy induction, was found in both the pSMAC and the cSMAC of the anergic synapse. This Cbl-b (and c-Cbl) accumulation at the anergic synapse may play an important role in anergy maintenance and/or induction. PMID:20207996

Metal accumulation in the polychaete Hediste japonica with emphasis on interaction between heavy metals and petroleum hydrocarbons

International Nuclear Information System (INIS)

Sun Fuhong; Zhou Qixing

2007-01-01

The accumulation of cadmium (Cd) and copper (Cu) in the polychaete Hediste japonica exposed to the mixture of Cd (or Cu) and petroleum hydrocarbons (PHCs) was investigated and compared with that exposed to single Cd (or Cu). The increased bioavailability of Cd or Cu with exposure concentrations resulted in an increase in the accumulation and net accumulation rate of Cd or Cu during single metal exposure. The net accumulation rate of Cd increased, but the net accumulation rate of Cu decreased with exposure time during single metal exposure, suggesting that H. japonica could actively regulate Cu burden in their body by inhibition of absolute uptake or promotion of excretion. The interactions between Cd (or Cu) and PHCs had complicated influences on the net accumulation rate of Cd and Cu in H. japonica under the condition of the binary mixture, which are dependent on their concentration combinations and exposure time. - The influences of petroleum hydrocarbons on Cd and Cu accumulation in H. japonica depend on their concentration combinations and exposure time

Hemoglobin induces monocyte recruitment and CD163-macrophage polarization in abdominal aortic aneurysm

DEFF Research Database (Denmark)

Rubio-Navarro, Alfonso; Amaro Villalobos, Juan Manuel; Lindholt, Jes S

2015-01-01

BACKGROUND: Increased hemoglobin (Hb) accumulation was reported in abdominal aortic aneurysms (AAAs). CD163 is a macrophage receptor involved in tissue Hb clearance, however its role in AAA has not been reported. We investigated the role of Hb on monocyte recruitment and differentiation towards CD......163 expressing macrophages ex vivo, in vitro and in human AAA. METHODS AND RESULTS: CD163 mRNA and protein expression was significantly higher in human AAA (n=7) vs. healthy wall (n=6). CD163 was predominantly found in adventitia of AAA, coinciding with areas rich in hemosiderin and adjacent...

Influence of cadmium stress on root exudates of high cadmium accumulating rice line (Oryza sativa L.).

Science.gov (United States)

Fu, Huijie; Yu, Haiying; Li, Tingxuan; Zhang, Xizhou

2018-04-15

A hydroponic experiment with two different cadmium (Cd) accumulating rice lines of Lu527-8 (the high Cd accumulating rice line) and Lu527-4 (the normal rice line) was carried out to explore the links among Cd stress, root exudates and Cd accumulation. The results showed that (1) Cd stress increased quantities of organic acids, but had no effect on composition in root exudates of the two rice lines. In Cd treatments, the contents of every detected organic acid in root exudates of Lu527-8 were 1.76-2.43 times higher than those of Lu527-4. Significant positive correlations between organic acids contents and Cd contents in plants were observed in both rice lines, except that malic acid was only highly relevant to Lu527-8, but not to Lu527-4. (2) Both composition and quantities of amino acids in root exudates changed a lot under Cd stress and this change differed in two rice lines. In control, four amino acids (glutamic acid, glycine, tyrosine and histidine) were detected in two rice lines. Under Cd stress, eight amino acids in Lu527-8 and seven amino acids in Lu527-4 could be detected, among which phenylalanine was only secreted by Lu527-8 and alanine, methionine and lysine were secreted by both rice lines. The contents of those four newly secreted amino acids from Lu527-8 increased significantly with the increase of Cd dose and each had a high-positive correlation with Cd contents, but the same change did not appear in Lu527-4. The difference between two rice lines in secretion of organic acids and amino acids may be related to their different Cd uptake properties. Copyright © 2017 Elsevier Inc. All rights reserved.

Is oxidative stress related to cadmium accumulation in the Mollusc Crassostrea angulata?

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Macías-Mayorga, Dayanara, E-mail: dayanara.macias@uleam.edu.ec [Instituto de Ciencias Marinas de Andalucía (CSIC), Campus Río San Pedro, S/N, 11510 Puerto Real, Cádiz (Spain); Departamento Central De Investigación (DCI), Universidad Laica Eloy Alfaro de Manabí, Vía San Mateo, Manta (Ecuador); Laiz, Irene [Departamento de Física Aplicada, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, Campus Río San Pedro, S/N, 11510 Puerto Real, Cádiz (Spain); Moreno-Garrido, Ignacio; Blasco, Julián [Instituto de Ciencias Marinas de Andalucía (CSIC), Campus Río San Pedro, S/N, 11510 Puerto Real, Cádiz (Spain)

2015-04-15

Highlights: • The cadmium accumulation in C. angulata tended toward a stationary state. • Metallothionein-like protein (MTLP) is clearly induced by Cd accumulation. • The MTLP detoxification mechanism is affected at high Cd concentrations. • Cadmium toxicity causes GSH levels to decrease and inhibits antioxidant enzymes. - Abstract: The kinetics of cadmium (Cd) accumulation in the gills and digestive gland of Crassotrea angulata at three concentrations of cadmium (0.088 μM, 0.44 μM and 2.22 μM) was monitored for 28 days. The relationship between accumulation and toxicity was studied using metallothionein-like protein (MTLP) concentration and reduced glutathione levels (GSH) as biochemical endpoints. The activity of enzymes which form part of the antioxidant defense system, in particular glutathione reductase (GR), total glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT), as enzymatic endpoints, was also assessed. A first order kinetic model demonstrated that the accumulation process does not take place linearly, as the Cd concentration in gills and digestive gland tended toward a stationary state. Metallothionein-like protein is clearly induced by Cd accumulation; however, at high Cd concentrations the detoxification mechanism of this protein is affected. High Cd concentrations (2.22 μM) lead to a decrease in GSH levels, and also inhibit antioxidant enzyme activities, demonstrating the adverse effect of this metal on the antioxidant balance system.

Is oxidative stress related to cadmium accumulation in the Mollusc Crassostrea angulata?

International Nuclear Information System (INIS)

Macías-Mayorga, Dayanara; Laiz, Irene; Moreno-Garrido, Ignacio; Blasco, Julián

2015-01-01

Highlights: • The cadmium accumulation in C. angulata tended toward a stationary state. • Metallothionein-like protein (MTLP) is clearly induced by Cd accumulation. • The MTLP detoxification mechanism is affected at high Cd concentrations. • Cadmium toxicity causes GSH levels to decrease and inhibits antioxidant enzymes. - Abstract: The kinetics of cadmium (Cd) accumulation in the gills and digestive gland of Crassotrea angulata at three concentrations of cadmium (0.088 μM, 0.44 μM and 2.22 μM) was monitored for 28 days. The relationship between accumulation and toxicity was studied using metallothionein-like protein (MTLP) concentration and reduced glutathione levels (GSH) as biochemical endpoints. The activity of enzymes which form part of the antioxidant defense system, in particular glutathione reductase (GR), total glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT), as enzymatic endpoints, was also assessed. A first order kinetic model demonstrated that the accumulation process does not take place linearly, as the Cd concentration in gills and digestive gland tended toward a stationary state. Metallothionein-like protein is clearly induced by Cd accumulation; however, at high Cd concentrations the detoxification mechanism of this protein is affected. High Cd concentrations (2.22 μM) lead to a decrease in GSH levels, and also inhibit antioxidant enzyme activities, demonstrating the adverse effect of this metal on the antioxidant balance system

Accumulation of heavy metal in scalp hair of people exposed in Beijing sewage discharge channel sewage irrigation area in Tianjin, China.

Science.gov (United States)

Wang, Zuwei; Yu, Xiaoman; Geng, Mingshuo; Wang, Zilu; Wang, Qianqian; Zeng, Xiangfeng

2017-05-01

Heavy metal concentrations in soil, wheat, and scalp hair exposed to Beijing sewage discharge channel sewage irrigation area (BSIA) in Tianjin were studied to evaluate the influence of sewage irrigation. Results showed that the continuous application of wastewater has led to an accumulation of heavy metals in the soil, with 55.2 and 8.62% of soil samples accumulating Cd and Zn, respectively, at concentrations exceeding the permissible limits in China. Concentrations of heavy metals in wheat grain from BSIA were higher than these from the clean water irrigation area by 63.2% for Cd, 3.8% for Cu, 100% for Pb, 6.6% for Zn, and 326.7% for Cr. The heavy metal bioaccumulation factor (BAF) of wheat/soil in BSIA showed the following order: Zn > Cd > Cu > Pb > Cr. Interestingly, these accumulation of heavy metals in soil after sewage irrigation could increase the migration ability of heavy metals (particularly Zn and Cd) from soil to wheat. Mean concentrations of heavy metals in the hair of residents followed the decreasing trend of Zn > Cu > Pb > Cr > Cd, which were higher than the control area by 110.0% for Cd, 20.0% for Cu, 55.9% for Zn, 36.6% for Pb, and 64.6% for Cr. Concentrations of heavy metals in male human hair in BSIA were higher than those of females. And the concentrations of heavy metals except for Pb in human hair increased with their increasing ages. The heavy metal BAF values of wheat/soil in BSIA showed the trend of Zn (98.0057) > Pb (7.0162) > Cr (5.5788) > Cu (5.4853) > Cd (3.5584); heavy metals had obvious biological amplification from wheat to human hair. These results indicated that local population health was potentially exposed to the heavy metal risk via wheat consumption.

Accumulation of uranium in plant roots absorbed from aqueous solutions

International Nuclear Information System (INIS)

Dohi, Terumi; Haga, Nobuhiko; Nakashima, Satoru; Tagai, Tokuhei

2007-01-01

In order to study accumulation mechanisms of uranium (U) in terrestrial plants, uptake experiments for U have been carried out by using Indian mustard (Brassica juncea). This plant is edible and known as a heavy metal accumulator, especially for cadmium (Cd). About 30 rootsstocks of Indian mustard grown hydroponically in laboratory dishes were kept in uranyl (UO 2 2+ ) nitrate solutions (initially 0.5 mmol/l) at 25degC for 24, 48 and 72 hours (h). The average U concentrations in leaves increased until 48 h up to about 0.6 mg/g and then decreased slightly. Those in roots showed similar trends, but with much higher maximum U concentrations of about 30 mg/g. Backscattered electron images under SEM of the roots showed that U was accumulated on the cell edges. EPMA elemental mapping indicated that phosphorus (P) distribution had a very strong correlation with that of U. The distribution of sulfur (S) appeared to be somewhat different form these U and P distributions. These results suggest that U can be absorbed into plant roots as uranyl (UO 2 2+ ) and might be fixed at the phospholipid rich cell membranes. This U accumulation mechanism appeared to be different from that for Cd which has a close association with S. (author)

Higher percentage of CD133+ cells is associated with poor prognosis in colon carcinoma patients with stage IIIB

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Zhang Xin

2009-07-01

Full Text Available Abstract Background Cancer stem cell model suggested that tumor progression is driven by the overpopulation of cancer stem cells and eradicating or inhibiting the symmetric division of cancer stem cells would become the most important therapeutic strategy. However, clinical evidence for this hypothesis is still scarce. To evaluate the overpopulation hypothesis of cancer stem cells the association of percentage of CD133+ tumor cells with clinicopathological parameters in colon cancer was investigated since CD133 is a putative cancer stem cell marker shared by multiple solid tumors. Patients and methods Tumor tissues matched with adjacent normal tissues were collected from 104 stage IIIB colon cancer patients who were subject to radical resection between January, 1999 to July, 2003 in this center. The CD133 expression was examined with immunohistochemical staining. The correlation of the percentage of CD133+ cell with clinicopathological parameters and patients' 5-year survival was analyzed. Results The CD133+ cells were infrequent and heterogeneous distribution in the cancer tissue. Staining of CD133 was localized not only on the glandular-luminal surface of cancer cells but also on the invasive budding and the poorly differentiated tumors with ductal structures. Both univariate and multivariate survival analysis revealed that the percentage of CD133+ cancer cells and the invasive depth of tumor were independently prognostic. The patients with a lower percentage of CD133+ cancer cells (less than 5% were strongly associated with a higher 5-year survival rate than those with a higher percentage of CD133+ cancer cells (greater than or equal to 55%. Additionally, no correlation was obtained between the percentage of CD133+ cancer cells and the other clinicopathological parameters including gender, age, site of primary mass, pathologic types, grades, and invasive depth. Conclusion The fact that a higher percentage CD133+ cells were strongly associated

PROFIL LOGAM BERAT Cd, Cr (VI DAN Pb PADA LOKASI BERBEDA DI PROVINSI LAMPUNG SERTA BIOAKUMULASINYA PADA TANAMAN PANGAN

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Hening Widowati

2015-11-01

Full Text Available The heavy metal profile analysis of Cd, Cr(VI and Pb in the different location in Lampung Province and their bioaccumulation to crops has been conducted. The aims were finding out the difference of metal accumulation in the different pollutant area and determining how it happened to the vegetables surrounding, which were kangkoong and spinach. The research methods were purposive sampling in the different location in Lampung Province, namely 1 highlands, 2 paddy fields, 3 road sides and 4industrial areas. Based on the results, it is found that the highest metal concentration of Cd, Cr(VI and Pb are in the industrial area. Commonly, the value of BCFo-w (0,12-2,00 is higher than BCF¬o-s (0,01-0,18 which shows that there is low metal accumulation of Cd, Cr(VI and Pb in kangkoong and spinach. Furthermore, the BCF value of Cd and Cr(VI are higher compared to Pb.  Keywords: Logam berat, Cd, Cr(VI, Pb,bioakumulasi.

Specific accumulation of 20 trace elements in great cormorants (Phalacrocorax carbo) from Japan

International Nuclear Information System (INIS)

Nam, Dong-Ha; Anan, Yasumi; Ikemoto, Tokutaka; Okabe, Yuko; Kim, Eun-Young; Subramanian, Annamalai; Saeki, Kazutoshi; Tanabe, Shinsuke

2005-01-01

This study is to elucidate the specific accumulation of 20 trace elements in tissues/organs of great cormorants from two different colonies (Lake Biwa and Mie) in Japan. In the body distribution of trace elements, some elements revealed tissue-specific accumulation such as most of the burden of Mo, Ag and Cd in liver, Tl and Cd in kidney, Cu, Rb and Cs in muscle, and V, Sr and Ba in bone. Gender-related variation was not observed in both populations for most of the trace elements, except for higher hepatic Sr in males from Lake Biwa. Hepatic V, muscular Hg and Tl, and Cd in liver, kidney and muscle increased with growth. Comparison of trace element levels in tissues between the two colonies showed that Cr, Rb, Sr, Cd, Cs, Ba and Tl levels were higher in Lake Biwa than in Mie, whereas Zn, Co and Hg in Mie samples were greater than Lake Biwa. Variations of elemental levels in stomach contents also showed similar patterns, thus, showing that dietary sources tended to be the main factor for these regional variations. Toxic Hg and Cd concentrations in the liver of cormorants from the two colonies were lower than those from other areas, implying relatively low exposure to these metals in the present study sites. Concentrations of V, Co, Ag, Cd, Cs, Hg, Tl, Pb and Bi in liver remained more or less at the same level between 1993 and 2003, while hepatic Cr, Mn, Cu, Zn, Se, Rb, Sr and Ba showed apparent decrease, which might be related to the biological factors. - Dietary sources seemed to be the main reason for variable results

Cadmium accumulation and elimination in tissues of juvenile olive flounder, Paralichthys olivaceus after sub-chronic cadmium exposure

International Nuclear Information System (INIS)

Kim, Seong-Gil; Jee, Jung-Hoon; Kang, Ju-Chan

2004-01-01

Cd accumulation and elimination in tissue of olive flounder. - Experiments were carried out to investigate the accumulation and elimination of cadmium (Cd) in tissues (gill, intestine, kidney, liver and muscle) of juvenile olive flounder, Paralichthys olivaceus, exposed to sub-chronic concentrations (0, 10, 50, 100 μg l -1 ) of Cd. Cd exposure resulted in an increased Cd accumulation in tissues of flounder with exposure periods and concentration, and Cd accumulation in gill and liver increased linearly with the exposure time. At 20 days of Cd exposure, the order of Cd accumulation in organs was gill > intestine > liver > kidney > muscle and after 30 days of exposure, those were intestine > gill > liver > kidney > muscle. An inverse relationship was observed between the accumulation factor (AF) and the exposure level, but AF showed an increase with exposure time. During the depuration periods, Cd concentration in the gill, intestine and liver decreased immediately following the end of the exposure periods. No significant difference was found Cd in concentration in the kidney and muscle during depuration periods. The order of Cd elimination rate in organs were decreased intestine > liver > gill during depuration periods

Adaptive response of arbuscular mycorrhizal symbiosis to accumulation of elements and translocation in Phragmites australis affected by cadmium stress.

Science.gov (United States)

Huang, Xiaochen; Ho, Shih-Hsin; Zhu, Shishu; Ma, Fang; Wu, Jieting; Yang, Jixian; Wang, Li

2017-07-15

Arbuscular mycorrhizal (AM) fungi have been reported to play a central role in improving plant tolerance to cadmium (Cd)-contaminated sites. This is achieved by enhancing both the growth of host plants and the nutritive elements in plants. This study assessed potential regulatory effects of AM symbiosis with regard to nutrient uptake and transport, and revealed different response strategies to various Cd concentrations. Phragmites australis was inoculated with Rhizophagus irregularis in the greenhouse cultivation system, where it was treated with 0-20 mg L -1 of Cd for 21days to investigate growth parameters, as well as Cd and nutritive element distribution in response to AM fungus inoculation. Mycorrhizal plants showed a higher tolerance, particularly under high Cd-level stress in the substrate. Moreover, our results determined the roots as dominant Cd reservoirs in plants. The AM fungus improved Cd accumulation and saturated concentration in the roots, thus inhibiting Cd uptake to shoots. The observed distributions of nutritive elements and the interactions among these indicated the highest microelement contribution to roots, Ca contributed maximally in leaves, and K and P contributed similarly under Cd stress. In addition, AM fungus inoculation effectively impacted Mn and P uptake and accumulation while coping with Cd toxicity. This study also demonstrated translocation factor from metal concentration (TF) could be a good parameter to evaluate different transportation strategies induced by various Cd stresses in contrast to the bioconcentration factor (BCF) and translocation factor from metal accumulation (TF'). Copyright © 2017 Elsevier Ltd. All rights reserved.

Cadmium tolerance and accumulation of Elsholtzia argyi origining from a zinc/lead mining site - a hydroponics experiment.

Science.gov (United States)

Li, Siliang; Wang, Fengping; Ru, Mei; Ni, Wuzhong

2014-01-01

In this study, a hydroponics experiment was conducted to investigate the characteristics of Cd tolerance and accumulation of Elsholtzia argyi natively growing on the soil with high levels of heavy metals in a Zn/Pb mining site. Seedlings of E. argyi grown for 4 weeks and then were treated with 0(CK), 5,10,15, 20, 25, 30, 40, 50,100 umM Cd for 21 days. Each treatment had three replications. No visual toxic symptoms on shoots of E. argyi were observed at Cd level < or = 50 muM. The results indicated that the dry biomass of each tissue and the whole plants of the treatments with < or =40 umM cadmium were similar to that of the control, implying that E. argyi was a cadmium tolerant plant. The results also showed that the shoot Cd concentration significantly (P < 0.05) increased with the increase in the Cd level in nutrient solution. The shoot Cd concentration of the treatment with 40 umM Cd was as high as 237.9 mg kg(-1), which was higher than 100 mg kg(-1), normally used as the threshold concentration for identifying the Cd hyperaccumulating plant. It could be concluded that E. argyi was a Cd tolerant and accumulating plant species.

Trace element accumulation and distribution in sunflower plants at the stages of flower bud and maturity

Directory of Open Access Journals (Sweden)

Susanna De Maria

2013-02-01

Full Text Available The aim of this study was to analyze the accumulation and distribution of cadmium (Cd, zinc (Zn and copper (Cu in different portions of plants of sunflower (Helianthus annuus L., cv. Oleko grown in soil with contaminants (5, 300, 400 mg kg–1 of Cd, Zn and Cu, respectively and without (untreated soil as a control from the emergence of cotyledon leaves until to two phenological stages: flower bud (R-1 and maturity (R- 9. Sunflower accumulated considerable amounts of heavy metals in both phenological stages showing slight reductions of dry matter production. At R-1 stage, Cd, Zn and Cu were accumulated mainly in the roots with concentrations respectively up to 5.4, 233 and 160 mg kg–1 of dry matter with a low translocation from roots to the aerial part. Yet at the R-1 stage, the bioconcentration factor (BCF of Cd showed a significantly higher value in the Cd-Zn-Cu treatment (0.27 with respect to the untreated control (0.02, vice versa was observed for Cu, whereas no significant difference between treatments was observed for Zn (0.12 on average. However among metals, Cd showed the highest value of BCF. Referring only to the epigeous portion, differences in the accumulation and distribution of the three metals in the treated plants were found in both phenological stages; indeed passing from flower bud to the maturity stage, Cd, Zn and Cu concentrations increased in the stems and leaves, particularly in the old ones, whereas decreased in the heads. Metal accumulation in the achenes was very low and never exceed the toxicity threshold value considered for livestock. The high storage of heavy metals in roots and the probable re-translocation of the three metals along the plant during the growing cycle could be considered as a strategy of sunflower to preserve young metabolically-active leaves and reproductive organs from toxic metal concentrations.

Effects of water management on arsenic and cadmium speciation and accumulation in an upland rice cultivar.

Science.gov (United States)

Hu, Pengjie; Ouyang, Younan; Wu, Longhua; Shen, Libo; Luo, Yongming; Christie, Peter

2015-01-01

Pot and field experiments were conducted to investigate the effects of water regimes on the speciation and accumulation of arsenic (As) and cadmium (Cd) in Brazilian upland rice growing in soils polluted with both As and Cd. In the pot experiment constant and intermittent flooding treatments gave 3-16 times higher As concentrations in soil solution than did aerobic conditions but Cd showed the opposite trend. Compared to arsenate, there were more marked changes in the arsenite concentrations in the soil solution as water management shifted, and therefore arsenite concentrations dominated the As speciation and bioavailability in the soil. In the field experiment As concentrations in the rice grains increased from 0.14 to 0.21 mg/kg while Cd concentrations decreased from 0.21 to 0.02 mg/kg with increasing irrigation ranging from aerobic to constantly flooding conditions. Among the various water regimes the conventional irrigation treatment produced the highest rice grain yield of 6.29 tons/ha. The As speciation analysis reveals that the accumulation of dimethylarsinic acid (from 11.3% to 61.7%) made a greater contribution to the increase in total As in brown rice in the intermittent and constant flooding treatments compared to the intermittent-aerobic treatment. Thus, water management exerted opposite effects on Cd and As speciation and bioavailability in the soil and consequently on their accumulation in the upland rice. Special care is required when irrigation regime methods are employed to mitigate the accumulation of metal(loid)s in the grain of rice grown in soils polluted with both As and Cd. Copyright © 2014. Published by Elsevier B.V.

Biochemical and photochemical feedbacks of acute Cd toxicity in Juncus acutus seedlings: The role of non-functional Cd-chlorophylls

Science.gov (United States)

Santos, D.; Duarte, B.; Caçador, I.

2015-12-01

The increasing metal pollution in salt marshes and its influence on the plants that inhabit these ecosystems, has become a major concern with serious implications on the species establishment. Juncus acutus is a highly common halophyte specie in Portuguese marshes. Seeds from his specie were exposed to a range of different Cd concentrations (0.05, 0.1, 0.5 and 1 μM) in order to evaluate the effects of acute Cd stress on seed germination and growth as well as on seedling pigment composition, photosynthetic apparatus and oxidative stress biomarkers. Seedling length was higher than in control in every Cd treatment, however biomass showed a decrease. It was also observed that increasing Cd treatments, lead to a proportional increase in the Cd tissue concentration. Also the Cd-substituted chlorophylls showed an increase with increasing Cd doses that were applied. This substitution results in a non-functional chlorophyll molecule, highly unstable under moderate light intensities which inevitably reduces the efficiency of the LHC II. As consequence, there was a decrease in the use-efficiency of the harvested energy, leading to a decay in the photosynthetic capacity and energy accumulation, which was dissipated as heat. As for the antioxidant enzymes, SOD and APX presented higher activity, responding to increasing cadmium concentrations. Thus, becomes evident that Cd affects negatively, both biochemically and photochemically, the establishment by seed process of J. acutus highlighting the potential of the use of this specie seed as potential sentinel and ecotoxicity test in extreme conditions.

Metal accumulation and antioxidant defenses in the freshwater fish Carassius auratus in response to single and combined exposure to cadmium and hydroxylated multi-walled carbon nanotubes

International Nuclear Information System (INIS)

Qu, Ruijuan; Wang, Xinghao; Wang, Zunyao; Wei, Zhongbo; Wang, Liansheng

2014-01-01

Highlights: • Cd and OH-MWCNTs have a synergistic effect on Carassius auratus. • OH-MWCNTs significantly increased Cd accumulation in liver after 12 d exposure. • Co-exposure to Cd and OH-MWCNTs evoked severe hepatic oxidative stress. - Abstract: The effects of cadmium, hydroxylated multi-walled carbon nanotubes, and their mixture on metal accumulation and antioxidant defenses were studied using the goldfish Carassius auratus as the test organism. The fish were exposed to 0.1 mg/L Cd, 0.5 mg/L OH-MWCNTs, or 0.1 mg/L Cd + 0.5 mg/L OH-MWCNTs for 3 and 12 days. Then, the Cd concentration was determined in the gill, liver and muscle. Moreover, hepatic antioxidant enzyme activity (superoxide dismutase, catalase and glutathione peroxidase), glutathione level and malondialdehyde content were also measured. A continuous accumulation of Cd was observed throughout the experimental period. Cd accumulation in tissues occurred in the following order: gill > liver > muscle at 3 days and liver > gill > muscle at 12 days. The concentrations of Cd in the livers of fish exposed to the combination of Cd + OH-MWCNTs were significantly higher than those in fish exposed to either single chemical after 12 d of exposure. Meanwhile, the mixture evoked severe oxidative stress in the exposed fish, as indicated by significant inhibition of SOD, CAT and GPx activity, a remarkable decrease in GSH level, and simultaneous elevation of MDA content. These results suggested that the effect of the combined factors on metal accumulation and oxidative stress biomarkers was more obvious than that of single factors at longer exposure durations

Metal accumulation and antioxidant defenses in the freshwater fish Carassius auratus in response to single and combined exposure to cadmium and hydroxylated multi-walled carbon nanotubes

Energy Technology Data Exchange (ETDEWEB)

Qu, Ruijuan; Wang, Xinghao; Wang, Zunyao, E-mail: wangzun315cn@163.com; Wei, Zhongbo; Wang, Liansheng

2014-06-30

Highlights: • Cd and OH-MWCNTs have a synergistic effect on Carassius auratus. • OH-MWCNTs significantly increased Cd accumulation in liver after 12 d exposure. • Co-exposure to Cd and OH-MWCNTs evoked severe hepatic oxidative stress. - Abstract: The effects of cadmium, hydroxylated multi-walled carbon nanotubes, and their mixture on metal accumulation and antioxidant defenses were studied using the goldfish Carassius auratus as the test organism. The fish were exposed to 0.1 mg/L Cd, 0.5 mg/L OH-MWCNTs, or 0.1 mg/L Cd + 0.5 mg/L OH-MWCNTs for 3 and 12 days. Then, the Cd concentration was determined in the gill, liver and muscle. Moreover, hepatic antioxidant enzyme activity (superoxide dismutase, catalase and glutathione peroxidase), glutathione level and malondialdehyde content were also measured. A continuous accumulation of Cd was observed throughout the experimental period. Cd accumulation in tissues occurred in the following order: gill > liver > muscle at 3 days and liver > gill > muscle at 12 days. The concentrations of Cd in the livers of fish exposed to the combination of Cd + OH-MWCNTs were significantly higher than those in fish exposed to either single chemical after 12 d of exposure. Meanwhile, the mixture evoked severe oxidative stress in the exposed fish, as indicated by significant inhibition of SOD, CAT and GPx activity, a remarkable decrease in GSH level, and simultaneous elevation of MDA content. These results suggested that the effect of the combined factors on metal accumulation and oxidative stress biomarkers was more obvious than that of single factors at longer exposure durations.

Impact of different feedstocks derived biochar amendment with cadmium low uptake affinity cultivar of pak choi (Brassica rapa ssb. chinensis L.) on phytoavoidation of Cd to reduce potential dietary toxicity.

Science.gov (United States)

Yasmin Khan, Kiran; Ali, Barkat; Cui, Xiaoqiang; Feng, Ying; Yang, Xiaoe; Joseph Stoffella, Peter

2017-07-01

Biochar has become eco-friendly amendment used for phytoavoidation with low cadmium (Cd) accumulating cultivars of crops to ensure food safety in Cd contaminated soils. In this study, biochar with different waste feedstock material were evaluated for their effectiveness on essential trace metals mobility, Cd bioavailability and its accumulation in two contrasting Cd accumulating cultivars of pak choi (Brassica rapa ssp. chinensis L.) grown in Cd contaminated Mollisol soil. A greenhouse experiment was conducted with plants grown in Cd contaminated soil that had been amended with biochar derived from barley straw, tomato green waste, chicken manure, duck manure and swine manure at application rate of 0%, 2.5% and 5.0% (w/w). The results showed that soil pH was significantly increased by all treatments. Biochar increased plant dry biomass, micronutrients bioavailability with significant differences in the Cd sorption capacity, with the effectiveness higher with increasing biochar application rate. However, tomato green waste (TGW) and chicken manure (CM) derived biochar were more effective than the other biochar in reducing Cd mobilization in soil by 35-54% and 26-43% and reduced its accumulation in shoots of pak choi cultivars by 34-76% and 33-72% in low Cd accumulator cultivar and 64-85% and 55-80% in high Cd accumulator cultivar than the control. Overall, results indicate that TGW and CM biochar can efficiently immobilize Cd, thereby reducing bioavailability in Cd contaminated Mollisol soil to ensure food safety. Copyright © 2017 Elsevier Inc. All rights reserved.

La Doping of CdS for Enhanced CdS/CdSe Quantum Dot Cosensitized Solar Cells

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Xiaolei Qi

2015-01-01

Full Text Available CdS/CdSe system of quantum dot cosensitized solar cells (QDCSCs is one of the most attractive structures for high-efficiency due to its effect of level adjusting. However, the stepwise structure formed between levels of CdS and CdSe has a limitation for enhancing the efficiencies. Metal ions doping in quantum dots have emerged as a common way for changing the Fermi level, band gap, and conductance. Here we report an innovative concept for the rare earth materials La-doped of the CdS layer in the CdS/CdSe QDCSCs by means of the successive ionic layer adsorption and reaction (SILAR. Then we tested that La doped quantum dots can help more electrons accumulate in CdS film, which makes the Fermi level shift up and form a stepped structure. This method leads to enhanced absorption intensity, obviously increasing current density in CdS/CdSe QDCSCs. Our research is a new exploration for improving efficiencies of quantum dot sensitized solar cells.

Foliar application of two silica sols reduced cadmium accumulation in rice grains

International Nuclear Information System (INIS)

Liu Chuanping; Li Fangbai; Luo Chunling; Liu Xinming; Wang Shihua; Liu Tongxu; Li Xiangdong

2009-01-01

In the present study, pot experiments were conducted to investigate the effects of foliar application of two silica (Si) sols on the alleviation of cadmium (Cd) toxicity in contaminated soil to rice. Results showed that the foliar application of Si sols significantly increased the dry weight of grains (without husk) and shoots in rice grown in Cd contaminated soil, whereas the Cd concentration in the grains and shoots decreased obviously. The total accumulation of Cd in rice grains also decreased with the application of both of the Si sols, but no significant effect was found on the Cd accumulation in the shoots. For the optimal effect, Si-sol-B should be foliar applied at the tillering-stage during rice growth. The mechanism of Si foliar application to alleviate the toxicity and accumulation of Cd in grains of rice may be related to the probable Cd sequestration in the shoot cell walls

Genotype variations in cadmium and lead accumulations of leafy lettuce (Lactuca sativa L.) and screening for pollution-safe cultivars for food safety.

Science.gov (United States)

Zhang, Kun; Yuan, Jiangang; Kong, Wei; Yang, Zhongyi

2013-06-01

Heavy-metals in polluted soils can accumulate in plants and threaten crop safety. To evaluate the risk of heavy-metal pollution in leafy lettuce (Lactuca sativa L.), two pot experiments were conducted to investigate Cd and Pb accumulation and transfer potential in 28 cultivars of lettuce and to screen for low-Cd and low-Pb accumulative cultivars. In the three treatments, 5.2-fold, 4.8-fold and 4.8-fold differences in the shoot Cd concentration were observed between the cultivars with the highest and the lowest Cd concentrations, respectively. This genotype variation was sufficiently large to identify low-Cd accumulative genotypes to reduce Cd contamination in food. Cadmium accumulation in the low-Cd accumulative genotypes was significantly positively correlated with Pb accumulation. At the cultivar level, Cd and Pb accumulation in lettuce was stable and genotype-dependent. High Pb soil levels did not affect shoot Cd accumulation in lettuce. Lettuce was concluded to be at high risk for Cd pollution and low risk for Pb pollution. Among the tested cultivars, cvs. SJGT, YLGC, N518, and KR17 had the lowest Cd and Pb accumulation abilities in shoots and are thus important parental material for breeding pollution-safe cultivars to minimize Cd and Pb accumulation.

Cadmium accumulation by muskmelon under salt stress in contaminated organic soil

Energy Technology Data Exchange (ETDEWEB)

Gabrijel, Ondrasek [University of Zagreb, Faculty of Agriculture, Svetosimunska 25, 10000 Zagreb (Croatia)], E-mail: gondrasek@agr.hr; Davor, Romic [University of Zagreb, Faculty of Agriculture, Svetosimunska 25, 10000 Zagreb (Croatia); Zed, Rengel [Soil Science and Plant Nutrition, Faculty of Natural and Agricultural Sciences, University of Western Australia, Crawley WA 6009 (Australia); Marija, Romic; Monika, Zovko [University of Zagreb, Faculty of Agriculture, Svetosimunska 25, 10000 Zagreb (Croatia)

2009-03-15

Human-induced salinization and trace element contamination are widespread and increasing rapidly, but their interactions and environmental consequences are poorly understood. Phytoaccumulation, as the crucial entry pathway for biotoxic Cd into the human foodstuffs, correlates positively with rhizosphere salinity. Hypothesising that organic matter decreases the bioavailable Cd{sup 2+} pool and therefore restricts its phytoextraction, we assessed the effects of four salinity levels (0, 20, 40 and 60 mM NaCl) and three Cd levels (0.3, 5.5 and 10.4 mg kg{sup -1}) in peat soil on mineral accumulation/distribution as well as vegetative growth and fruit yield parameters of muskmelon (Cucumis melo L.) in a greenhouse. Salt stress reduced shoot biomass and fruit production, accompanied by increased Na and Cl and decreased K concentration in above-ground tissues. A 25- and 50-day exposure to salinity increased Cd accumulation in leaves up to 87% and 46%, respectively. Accumulation of Cd in the fruits was up to 43 times lower than in leaves and remained unaltered by salinity. Soil contamination by Cd enhanced its accumulation in muskmelon tissues by an order of magnitude compared with non-contaminated control. In the drainage solution, concentrations of Na and Cl slightly exceeded those in the irrigation solution, whereas Cd concentration in drainage solution was lower by 2-3 orders of magnitude than the total amount added. Chemical speciation and distribution modelling (NICA-Donnan) using Visual MINTEQ showed predominance of dissolved organic ligands in Cd chemisorption and complexation in all treatments; however, an increase in salt addition caused a decrease in organic Cd complexes from 99 to 71%, with free Cd{sup 2+} increasing up to 6% and Cd-chlorocomplexes up to 23%. This work highlights the importance of soil organic reactive surfaces in reducing trace element bioavailability and phytoaccumulation. Chloride salinity increased Cd accumulation in leaves but not in fruit

Dynamic changes in radial oxygen loss and iron plaque formation and their effects on Cd and As accumulation in rice (Oryza sativa L.).

Science.gov (United States)

Wang, Xun; Yao, Haixin; Wong, Ming Hung; Ye, Zhihong

2013-12-01

Temporal variations and correlations between radial oxygen loss (ROL), iron (Fe) plaque formation, cadmium (Cd) and arsenic (As) accumulation were investigated in two rice cultivars at four different growth stages based upon soil pot and deoxygenated solution experiments. The results showed that there were significant differences in ROL (1.1-16 μmol O(2) plant(-1) h(-1)), Fe plaque formation (4,097-36,056 mg kg(-1)), Cd and As in root tissues (Cd 77-162 mg kg(-1); As 49-199 mg kg(-1)) and Fe plaque (Cd 0.4-24 mg kg(-1); As 185-1,396 mg kg(-1)) between these growth stages. ROL and Fe plaque increased dramatically from tillering to ear emergence stages and then were much reduced at the grain-filling stage. Furthermore, significantly positive correlations were detected between ROL and concentrations of Fe, Cd and As in Fe plaque. Our study indicates that increased Fe plaque forms on rice roots at the ear emergence stage due to the increased ROL. This stage could therefore be an important period to limit the transfer and distribution of Cd and As in rice plants when growing in soils contaminated with these toxic elements.

Detection of atherosclerotic lesions and intimal macrophages using CD36-targeted nanovesicles.

Science.gov (United States)

Nie, Shufang; Zhang, Jia; Martinez-Zaguilan, Raul; Sennoune, Souad; Hossen, Md Nazir; Lichtenstein, Alice H; Cao, Jun; Meyerrose, Gary E; Paone, Ralph; Soontrapa, Suthipong; Fan, Zhaoyang; Wang, Shu

2015-12-28

Current approaches to the diagnosis and therapy of atherosclerosis cannot target lesion-determinant cells in the artery wall. Intimal macrophage infiltration promotes atherosclerotic lesion development by facilitating the accumulation of oxidized low-density lipoproteins (oxLDL) and increasing inflammatory responses. The presence of these cells is positively associated with lesion progression, severity and destabilization. Hence, they are an important diagnostic and therapeutic target. The objective of this study was to noninvasively assess the distribution and accumulation of intimal macrophages using CD36-targeted nanovesicles. Soy phosphatidylcholine was used to synthesize liposome-like nanovesicles. 1-(Palmitoyl)-2-(5-keto-6-octene-dioyl) phosphatidylcholine was incorporated on their surface to target the CD36 receptor. All in vitro data demonstrate that these targeted nanovesicles had a high binding affinity for the oxLDL binding site of the CD36 receptor and participated in CD36-mediated recognition and uptake of nanovesicles by macrophages. Intravenous administration into LDL receptor null mice of targeted compared to non-targeted nanovesicles resulted in higher uptake in aortic lesions. The nanovesicles co-localized with macrophages and their CD36 receptors in aortic lesions. This molecular target approach may facilitate the in vivo noninvasive imaging of atherosclerotic lesions in terms of intimal macrophage accumulation and distribution and disclose lesion features related to inflammation and possibly vulnerability thereby facilitate early lesion detection and targeted delivery of therapeutic compounds to intimal macrophages. Copyright © 2015 Elsevier B.V. All rights reserved.

CD49a Expression Defines Tissue-Resident CD8+ T Cells Poised for Cytotoxic Function in Human Skin

DEFF Research Database (Denmark)

Cheuk, Stanley; Schlums, Heinrich; Sérézal, Irène Gallais

2017-01-01

with vitiligo, where melanocytes are eradicated locally, CD8+CD49a+ Trm cells that constitutively expressed perforin and granzyme B accumulated both in the epidermis and dermis. Conversely, CD8+CD49a– Trm cells from psoriasis lesions predominantly generated IL-17 responses that promote local inflammation...

Heavy metal accumulation potential and medicinal property of Bacopa monnieri - a paradox

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Nabeesa Salim

2011-12-01

Full Text Available Bioaccumulation of Mercury and Cadmium in Bacopa monnieri (L. Pennell, cultivated in Hoagland medium artificially contaminated with micro quantities of HgCl2 and CdCl2 is investigated. Bioaccumulation potential of B. monnieri is more towards Cd than Hg. Absorption and translocation of Hg and Cd are proportional to the availability of the metal in the growth media and period of growth. Effect of acidic pH showed enhanced accumulation while basic pH resulted in significant reduction in the accumulation of Hg and exorbitant reduction of Cd. As a result of combined treatment of HgCl2 and CdCl2, accumulation was very low in both acidic and basic pH. In addition to pH, antagonistic effect of Ca2+ present in lime water which was added to raise the pH of the growth medium also controls the accumulation and absorption of Hg and Cd ions. Bioaccumulation of Hg and Cd in B. monnieri reveals the phytoremediation potential while the bioaccumulation is hazards to health since the plant is highly medicinal and one important ingredient of many Ayurvedic preparations.

Accumulation of Trace Metals in Anadara granosa and Anadara inaequivalvis from Pattani Bay and the Setiu Wetlands.

Science.gov (United States)

Pradit, Siriporn; Shazili, Noor Azhar Mohamed; Towatana, Prawit; Saengmanee, Wuttipong

2016-04-01

This study was undertaken to assess the levels of trace metals (As, Cd, Cu, Pb, and Zn) in two common species of cockles (Anadara granosa and Anadara inaequivalvis) from two coastal areas in Thailand (Pattani Bay) and Malaysia (the Setiu Wetlands). A total of 350 cockles were collected in February and September 2014. Trace metals were determined by Inductively Coupled Plasma Mass Spectrometry. We observed that cockles in both areas had a higher accumulation of metals in September. Notably, the biota-sediment accumulation (BSAF) of Cd was highest in both areas. A strong positive correlation of Cd with the length of the cockles at Pattani Bay (r(2) = 0.597) and the Setiu Wetlands (r(2) = 0.675) was noted. It was suggested that As could be a limiting element (BSAF Malaysia Food Regulations, mean values of As, Cd, Cu, Pb, and Zn were within acceptable limits, but the maximum values of Cd and Pb exceeded the limits for both areas. Regular monitoring of trace metals in cockles from both areas is suggested for more definitive contamination determination.

Water Management Practices Affect Arsenic and Cadmium Accumulation in Rice Grains

OpenAIRE

Sun, Liming; Zheng, Manman; Liu, Hongyan; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Nie, Lixiao

2014-01-01

Cadmium (Cd) and arsenic (As) accumulation in rice grains is a great threat to its productivity, grain quality, and thus human health. Pot and field studies were carried out to unravel the effect of different water management practices (aerobic, aerobic-flooded, and flooded) on Cd and As accumulation in rice grains of two different varieties. In pot experiment, Cd or As was also added into the soil as treatment. Pots without Cd or As addition were maintained as control. Results indicated that...

Study on accumulation mechanism for heavy metal in hyper-accumulating plants by synchrotron radiation x-ray analysis

International Nuclear Information System (INIS)

Hokura, Akiko; Kitajima, Nobuyuki; Terada, Yasuko; Nakai, Izumi

2010-01-01

Some plants accumulate heavy metal elements such as As, Cd, and Pb, etc., and these plants have been focused on from the perspective of their application to phytoremediation. In order to understand the accumulation mechanism, the distribution and the chemical form of heavy metal should be revealed at cellular level. Here, we have introduced the recent works regarding arsenic hyperaccumulating fern (Pteris vittata L.) and cadmium hyperaccumulating plant (Arabidopsis halleri ssp. gemmifera). A combination of μ-XRF and μ-XANES techniques excited by high-energy X-ray microbeam with 1 μm resolution has proved to be an indispensable tool for the study of Cd accumulation in biological samples on a cellular scale. The sample-preparation techniques were also summarized. (author)

Regulatory function of cytomegalovirus-specific CD4+CD27-CD28- T cells

International Nuclear Information System (INIS)

Tovar-Salazar, Adriana; Patterson-Bartlett, Julie; Jesser, Renee; Weinberg, Adriana

2010-01-01

CMV infection is characterized by high of frequencies of CD27 - CD28 - T cells. Here we demonstrate that CMV-specific CD4 + CD27 - CD28 - cells are regulatory T cells (T R ). CD4 + CD27 - CD28 - cells sorted from CMV-stimulated PBMC of CMV-seropositive donors inhibited de novo CMV-specific proliferation of autologous PBMC in a dose-dependent fashion. Compared with the entire CMV-stimulated CD4 + T-cell population, higher proportions of CD4 + CD27 - CD28 - T R expressed FoxP3, TGFβ, granzyme B, perforin, GITR and PD-1, lower proportions expressed CD127 and PD1-L and similar proportions expressed CD25, CTLA4, Fas-L and GITR-L. CMV-CD4 + CD27 - CD28 - T R expanded in response to IL-2, but not to CMV antigenic restimulation. The anti-proliferative effect of CMV-CD4 + CD27 - CD28 - T R significantly decreased after granzyme B or TGFβ inhibition. The CMV-CD4 + CD27 - CD28 - T R of HIV-infected and uninfected donors had similar phenotypes and anti-proliferative potency, but HIV-infected individuals had higher proportions of CMV-CD4 + CD27 - CD28 - T R . The CMV-CD4 + CD27 - CD28 - T R may contribute to the downregulation of CMV-specific and nonspecific immune responses of CMV-infected individuals.

Cadmium accumulation in and tolerance of rice (Oryza sativa L.) varieties with different rates of radial oxygen loss

International Nuclear Information System (INIS)

Wang, M.Y.; Chen, A.K.; Wong, M.H.; Qiu, R.L.; Cheng, H.; Ye, Z.H.

2011-01-01

Cadmium (Cd) uptake and tolerance were investigated among 20 rice cultivars based on a field experiment (1.2 mg Cd kg -1 in soil) and a soil pot trial (control, 100 mg Cd kg -1 ), and rates of radial oxygen loss (ROL) were measured under a deoxygenated solution. Significant differences were found among the cultivars in: (1) brown rice Cd concentrations (0.11-0.29 mg kg -1 ) in a field soil, (2) grain Cd tolerance (34-113%) and concentrations (2.1-6.5 mg kg -1 ) in a pot trial, and (3) rates of ROL (15-31 mmol O 2 kg -1 root d.w. h -1 ). Target hazard quotients were calculated for the field experiment to assess potential Cd risk. Significant negative relationships were found between rates of ROL and concentrations of Cd in brown rice or straw under field and greenhouse conditions, indicating that rice cultivars with higher rates of ROL had higher capacities for limiting the transfer of Cd to rice and straw. - Highlights: → There are significant differences in brown rice Cd concentrations and rates of ROL among the rice cultivars. → The rates of ROL are significantly correlated with concentrations of Cd in brown rice. → Rice cultivars with higher rates of ROL have higher capacities for limiting the transfer of Cd to rice and straw. - Rice cultivars with high rates of ROL tended to accumulate low Cd in grains.

[Analysis and assessment of atmospheric pollution based on accumulation characterization of heavy metals in Platanus acerifolia leaves].

Science.gov (United States)

Liu, Ling; Fang, Yan-Ming; Wang, Shun-Chang; Xie, Ying; Wang, Cheng-Run

2014-03-01

The present work was aimed to evaluate the heavy metal pollution in the atmosphere of Huainan City. We measured and clustered the accumulation of six heavy metals in Platanus acerifolia leaves in 20 sampling fields with six types of environmental conditions, and analyzed the EF value of heavy metal enrichment in the leaves. The results showed that the accumulations in Platanus acerifolia leaves varied according to different types of metals, following the order of Zn > Cu > Cr > Ni > Pb > Cd. Environmental conditions also had great influence on the accumulation of heavy metals. Cd and Cu were mostly found in cement plant and mine, respectively, and Cr, Ni, Pb and Zn were significant higher in main road, compared with other environmental conditions. The average values of EF for all the metals expect Cr in scenic and village area were over 1. The average values of EF for all the metals in mine, power plant, main road and cement plant were above 3. The overall pollution condition of heavy metals in Huainan City followed the order of Cd > Cu > Zn > Ni > Pb > Cr.

[Changes of CD34(+) and CD71(+)CD45(-) cell levels in bone marrow of MDS and AA patients].

Science.gov (United States)

Yan, Zhen-Yu; Tian, Xu; Li, Ying; Yang, Mei-Rong; Zhang, Song; Wang, Xie-Ming; Zhang, Hai-Xia; Cheng, Nai-Yao

2014-04-01

This study was aimed to investigate the changes of CD34(+) and CD71(+)CD45(-) cell levels in MDS and AA patients. A total of 25 cases MDS and 43 cases of AA (18 cases SAA and 25 cases of NSAA) from January 2010 to October 2013 in the Department of Hematology, affiliated hospital of Hebei United University were enrolled in this study. The complete blood count, bone marrow smears, bone marrow biopsy, karyotype analysis and bone marrow blood cell immune genotyping (mainly the proportion of CD34(+) cells, CD71(+)CD45(-) cells in nucleated cells) were carried out for all patients; the changes of CD34(+) and CD71(+)CD45(-) cell levels in patients with MDS and AA (SAA NSAA) were compared; the differences of white blood cell count, platelet count and hemoglobin concentration in patients with count of CD71(+)CD45(-) ≥ 15% or MDS group was higher than that in AA (NSAA and SAA) group (P MDS group was higher than that in SAA (P MDS group. In MDS group with CD71(+)CD45(-) ≥ 15%, the platelet count was significantly higher than that in NSAA group (P MDS and NSAA group with CD71(+)CD45(-) 0.05). It is concluded that the count of CD34(+) cells in MDS patients is significantly higher than that in AA and SAA patients. The count of CD71(+)CD45(-) cells in MDS group is significantly higher than that of SAA group. The platelet count in MDS patients with CD71(+)CD45(-) cells ≥ 15% is significantly higher than that of the NSAA group.

Accumulation of metal ions by pectinates

Science.gov (United States)

Deiana, S.; Deiana, L.; Palma, A.; Premoli, A.; Senette, C.

2009-04-01

The knowledge of the mechanisms which regulate the interactions of metal ions with partially methyl esterified linear polymers of α-1,4 linked D-galacturonic acid units (pectinates), well represented in the root inner and outer apoplasm, is of great relevance to understand the processes which control their accumulation at the soil-root interface as well as their mobilization by plant metabolites. Accumulation of a metal by pectinates can be affected by the presence of other metals so that competition or distribution could be expected depending on the similar or different affinity of the metal ions towards the binding sites, mainly represented by the carboxylate groups. In order to better understand the mechanism of accumulation in the apoplasm of several metal ions, the sorption of Cd(II), Zn(II), Cu(II), Pb(II) and Cr(III) by a Ca-polygalacturonate gel, used as model of the soil-root interface, with a degree of esterification of 18% (PGAE1) and 65% (PGAE2) was studied at pH 3.0, 4.0, 5.0 and 6.0 in the presence of CaCl2 2.5 mM.. The results show that sorption increases with increasing both the initial metal concentration and pH. A similar sorption trend was evidenced for Cu(II) and Pb(II) and for Zn(II) and Cd(II), indicating that the mechanism of sorption for these two ionic couples is quite different. As an example, at pH 6.0 and an initial metal concentration equal to 2.0 mM, the amount of Cu(II) and Pb(II) sorbed was about 1.98 mg-1 of PGAE1 while that of Cd(II) and Zn(II) was about 1.2 mg-1. Cr(III) showed a rather different sorption trend and a much higher amount (2.8 mg-1of PGAE1 at pH 6.0) was recorded. The higher affinity of Cr(III) for the polysaccharidic matrix is attributable to the formation of Cr(III) polynuclear species in solution, as shown by the distribution diagrams obtained through the MEDUSA software. On the basis of these findings, the following affinity towards the PGAE1 can be assessed: Cr(III) > Cu(II) ? Pb(II) > Zn (II) ? Cd

Phytoextraction of Cd-contaminated soil by carambola (Averrhoa carambola) in field trials.

Science.gov (United States)

Li, J T; Liao, B; Dai, Z Y; Zhu, R; Shu, W S

2009-08-01

Use of metal-accumulating woody species to extract metals from heavy metal contaminated soil has received more attention. While considerable studies have focused on the phytoextraction potential of willow (Salix spp.) and poplar (Populus spp.), similar information is rare for other woody species. Carambola (Averrhoa carambola) is a high-biomass tree and has been identified as a new Cd-accumulating species. The present study aimed to evaluate the Cd phytoextraction potential of carambola under field condition. After growing in a slightly Cd-contaminated site for about 170 d, the carambola stand initiated by seed-seedling with high planting density (encoded with "HD-1yr") attained a high shoot biomass yield of 18.6 t ha(-1) and extracted 213 g Cdha(-1), resulting in a 1.6-fold higher Cd removal efficiency than that of a contrasting stand established by grafted-seedling with low planting density (5.3% vs. 2%). That is, "HD-1yr" would remove 50% of the total soil Cd with 13yr, assuming that the Cd removal efficiency would not change over time. Further, one crop of "HD-1yr" significantly decreased (63-69%) the Cd uptake by subsequent vegetables. Among the four carambola stands established using grafted-seedling, the 2-yr-old stand exhibited the highest annual Cd removal efficiency (3.7%), which was yet lower than that of "HD-1yr". These results suggested that phytoextraction of Cd by carambola (especially for "HD-1yr" stand) presented a feasible option to clean up agricultural soils slightly contaminated by Cd.

Evaluating Insects as Bioindicators of Heavy Metal Contamination and Accumulation near Industrial Area of Gujrat, Pakistan

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Iqra Azam

2015-01-01

Full Text Available To study the accumulation and contamination of heavy metals (i.e., Cd, Cr, Cu, Ni, and Zn in soil, air, and water, few insect species were assayed as ecological indicators. Study area comes under industrial zone of district Gujrat of Punjab, Pakistan. Insects used as bioindicators included a libellulid dragonfly (Crocothemis servilia, an acridid grasshopper (Oxya hyla hyla, and a nymphalid butterfly (Danaus chrysippus near industrial zone of Gujrat. Accumulation of Cd was highest in insect species followed by Cu, Cr, Zn, and Ni at p<0.05. Hierarchical cluster analysis (HACA was carried out to study metal accumulation level in all insects. Correlation and regression analysis confirmed HACA observations and declared concentration of heavy metals above permissible limits. Metal concentrations in insects were significantly higher near industries and nallahs in Gujrat and relatively higher concentrations of metals were found in Orthoptera than Odonata and Lepidoptera. The total metal concentrations in insects were pointed significantly higher at sites S3 (Mid of HalsiNala, S9 (End of HalsiNala, and S1 (Start of HalsiNala, whereas lowest value was detected at site S6 (Kalra Khasa located far from industrial area. HACA indicates that these insect groups are potential indicators of metal contamination and can be used in biomonitoring.

Characterization of cadmium-resistant bacteria and their potential for reducing accumulation of cadmium in rice grains

International Nuclear Information System (INIS)

Lin, Xiaoyan; Mou, Renxiang; Cao, Zhaoyun; Xu, Ping; Wu, Xiaoliang; Zhu, Zhiwei; Chen, Mingxue

2016-01-01

Cadmium (Cd) pollution is a serious widespread environmental problem that not only destroys the microbial ecology of soil and decreases crop production, but also poses a serious risk to human health. Many methods have been used for the remediation of Cd pollution but none of these is totally satisfactory. Microbial remediation strategies have attracted increasing interest since they are environmentally friendly and cost-effective. In the present study, three Cd-resistant bacteria were isolated and evaluated for potential application in Cd bioremediation. Based on their morphological, physiological and biochemical characteristics, together with 16S rDNA gene sequence analyses, bacteria were identified as Stenotrophomonas acidaminiphila (2#), Pseudomonas aeruginosa (9#) and Delftia tsuruhatensis (12#). Pseudomonas aeruginosa showed very high tolerance to metals, especially Cd (2200 mg/L), Zn (1800 mg/L) and Pb (1200 mg/L), and is thought to be a multi-metal-resistant bacterium. Pseudomonas aeruginosa was also sensitive to 13 different antibiotics. The effects of the bacterial strains on the growth of rice plants and their ability to reduce Cd accumulation from Cd-contaminated soils in pot experiments were also evaluated. For Oryza sativa L. A grown in contaminated soil (3 mg/kg Cd), the accumulation of Cd was decreased by 31.2 and 25.5% in brown rice and polished rice, respectively, by strain 9#; Pseudomonas aeruginosa was more effective in reducing Cd accumulation in rice grains than a mixture of strains. For Oryza sativa L. B, a mixture of strains acting synergistically was more effective than a single strain in reducing Cd accumulation; treatment with mixed strains (strains + 3 mg/kg Cd) resulted in 41.3, 35.9, and 32.6% reductions in Cd accumulation in unhulled rice, brown rice and polished rice, respectively. Although different results were obtained for two rice varieties, it can still be concluded that Cd-resistant bacteria are suitable for reducing Cd

Characterization of cadmium-resistant bacteria and their potential for reducing accumulation of cadmium in rice grains

Energy Technology Data Exchange (ETDEWEB)

Lin, Xiaoyan; Mou, Renxiang; Cao, Zhaoyun; Xu, Ping; Wu, Xiaoliang; Zhu, Zhiwei; Chen, Mingxue, E-mail: cmingxue@126.com

2016-11-01

Cadmium (Cd) pollution is a serious widespread environmental problem that not only destroys the microbial ecology of soil and decreases crop production, but also poses a serious risk to human health. Many methods have been used for the remediation of Cd pollution but none of these is totally satisfactory. Microbial remediation strategies have attracted increasing interest since they are environmentally friendly and cost-effective. In the present study, three Cd-resistant bacteria were isolated and evaluated for potential application in Cd bioremediation. Based on their morphological, physiological and biochemical characteristics, together with 16S rDNA gene sequence analyses, bacteria were identified as Stenotrophomonas acidaminiphila (2#), Pseudomonas aeruginosa (9#) and Delftia tsuruhatensis (12#). Pseudomonas aeruginosa showed very high tolerance to metals, especially Cd (2200 mg/L), Zn (1800 mg/L) and Pb (1200 mg/L), and is thought to be a multi-metal-resistant bacterium. Pseudomonas aeruginosa was also sensitive to 13 different antibiotics. The effects of the bacterial strains on the growth of rice plants and their ability to reduce Cd accumulation from Cd-contaminated soils in pot experiments were also evaluated. For Oryza sativa L. A grown in contaminated soil (3 mg/kg Cd), the accumulation of Cd was decreased by 31.2 and 25.5% in brown rice and polished rice, respectively, by strain 9#; Pseudomonas aeruginosa was more effective in reducing Cd accumulation in rice grains than a mixture of strains. For Oryza sativa L. B, a mixture of strains acting synergistically was more effective than a single strain in reducing Cd accumulation; treatment with mixed strains (strains + 3 mg/kg Cd) resulted in 41.3, 35.9, and 32.6% reductions in Cd accumulation in unhulled rice, brown rice and polished rice, respectively. Although different results were obtained for two rice varieties, it can still be concluded that Cd-resistant bacteria are suitable for reducing Cd

The enhancement by arbuscular mycorrhizal fungi of the Cd remediation ability and bioenergy quality-related factors of five switchgrass cultivars in Cd-contaminated soil

Directory of Open Access Journals (Sweden)

Hong Sun

2018-03-01

Full Text Available A greenhouse experiment was carried out to investigate the effects of arbuscular mycorrhizal fungi (AMF on the growth, P and Cd concentrations and bioenergy quality-related factors of five cultivars of switchgrass, including three lowland cultivars (Alamo (Ala, Kanlow (Kan, Performer (Per and two highland cultivars (Blackwell (Bw, Summer (Sum, with 0, 1 and 10 mg/kg Cd addition levels. The results showed that AMF inoculation notably increased the biomass and P concentrations of all the cultivars. The Cd concentrations in the roots were higher than those in the shoots of all cultivars irrespective of inoculation, but the AMF had different effects on Cd accumulation in highland and lowland cultivars. AMF inoculation decreased the shoot and root concentrations in Ala and Kan, increased the shoot and root concentrations of Cd in Bw and Sum, and increased shoot Cd concentrations and decreased root Cd concentrations in Per. The highest Cd concentrations were detected in the roots of Bw and in the shoots of Sum with AMF symbiosis. Bw contained the highest total extracted Cd which was primarily in the roots. Ala had the second highest extracted Cd in the shoots, reaching 32% with 1 mg/kg of added Cd, whereas Sum had the lowest extracted Cd. AMF symbiosis had varied effects on bioenergy quality-related factors: for example, AMF decreased the ash lignin content in Ala and the C/N in Sum, increased the nitrogen, gross calorie values, and maintained the hemicellulose and cellulose contents in all cultivars with all tested concentrations of Cd. A principal component analysis (PCA showed that AMF inoculation could enhance, weaken or transform (positive-negative, PC1-PC2 the correlations of these factors with the principle components under Cd stress. Therefore, AMF symbiosis enhanced the growth of different cultivars of switchgrass, increased/decreased Cd accumulation, promoted Cd extraction, and regulated the bioenergy quality-related factors in Cd

A Diffusive Gradient-in-Thin-Film Technique for Evaluation of the Bioavailability of Cd in Soil Contaminated with Cd and Pb

Science.gov (United States)

Wang, Peifang; Wang, Teng; Yao, Yu; Wang, Chao; Liu, Cui; Yuan, Ye

2016-01-01

Management of heavy metal contamination requires accurate information about the distribution of bioavailable fractions, and about exchange between the solid and solution phases. In this study, we employed diffusive gradients in thin-films (DGT) and traditional chemical extraction methods (soil solution, HOAc, EDTA, CaCl2, and NaOAc) to determine the Cd bioavailability in Cd-contaminated soil with the addition of Pb. Two typical terrestrial species (wheat, Bainong AK58; maize, Zhengdan 958) were selected as the accumulation plants. The results showed that the added Pb may enhance the efficiency of Cd phytoextraction which is indicated by the increasing concentration of Cd accumulating in the plant tissues. The DGT-measured Cd concentrations and all the selected traditional extractants measured Cd concentrations all increased with increasing concentration of the addition Pb which were similar to the change trends of the accumulated Cd concentrations in plant tissues. Moreover, the Pearson regression coefficients between the different indicators obtained Cd concentrations and plants uptake Cd concentrations were further indicated significant correlations (p < 0.01). However, the values of Pearson regression coefficients showed the merits of DGT, CaCl2, and Csol over the other three methods. Consequently, the in situ measurement of DGT and the ex situ traditional methods could all reflect the inhibition effects between Cd and Pb. Due to the feature of dynamic measurements of DGT, it could be a robust tool to predict Cd bioavaiability in complex contaminated soil. PMID:27271644

A Diffusive Gradient-in-Thin-Film Technique for Evaluation of the Bioavailability of Cd in Soil Contaminated with Cd and Pb

Directory of Open Access Journals (Sweden)

Peifang Wang

2016-06-01

Full Text Available Management of heavy metal contamination requires accurate information about the distribution of bioavailable fractions, and about exchange between the solid and solution phases. In this study, we employed diffusive gradients in thin-films (DGT and traditional chemical extraction methods (soil solution, HOAc, EDTA, CaCl2, and NaOAc to determine the Cd bioavailability in Cd-contaminated soil with the addition of Pb. Two typical terrestrial species (wheat, Bainong AK58; maize, Zhengdan 958 were selected as the accumulation plants. The results showed that the added Pb may enhance the efficiency of Cd phytoextraction which is indicated by the increasing concentration of Cd accumulating in the plant tissues. The DGT-measured Cd concentrations and all the selected traditional extractants measured Cd concentrations all increased with increasing concentration of the addition Pb which were similar to the change trends of the accumulated Cd concentrations in plant tissues. Moreover, the Pearson regression coefficients between the different indicators obtained Cd concentrations and plants uptake Cd concentrations were further indicated significant correlations (p < 0.01. However, the values of Pearson regression coefficients showed the merits of DGT, CaCl2, and Csol over the other three methods. Consequently, the in situ measurement of DGT and the ex situ traditional methods could all reflect the inhibition effects between Cd and Pb. Due to the feature of dynamic measurements of DGT, it could be a robust tool to predict Cd bioavaiability in complex contaminated soil.

Heavy metal accumulation by carrageenan and agar producing algae

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Burdin, K.S. [Moscow State Univ. (Russian Federation). Faculty of Biology; Bird, K.T. [North Carolina Univ., Wilmington, NC (United States). Center for Marine Science Research

1994-09-01

The accumulation of six heavy metals Cu, Cd, Ni, Zn, Mn and Pb was measured in living and lzophilized algal thalli. The agar producing algae were Gracilaria tikvahiae and Gelidium pusillum. The carrageenan producing macroalgae were Agardhiella subulata and the gametophyte and tetrasporophyte phases of Chondrus crispus. These produce primarily iota, kappa and lambda carrageenans, respectively. At heavy metal concentrations of 0.5 mg L{sup -1}, living thalli of Gracilaria tikvahiae generally showed the greatest amount of accumulation of the 6 heavy metals tested. The accumulation of Pb was greater in the living thalli of all four species than in the lyophilized thalli. Except for Agardhiella subulata, lyophilized thalli showed greater accumulation of Ni, Cu and Zn. There was no difference in heavy metal accumulation between living and lyophilized thalli in the accumulation of Cd. Manganese showed no accumulation at the tested concentration. There did not appear to be a relationship between algal hydrocolloid characteristics and the amounts of heavy metals accumulated. (orig.)

Comparative studies on Pb and Cd levels in parasites of terrestrial and aquatic animals

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Sures, B.; Taraschewski, H. [Univ. Karlsruhe (Germany). Zoologisches Institut-Okologie

1995-12-31

Several fish parasites (Acanthocephala, Cestoda, Nematoda) and organs of their respective intermediate and final hosts were analyzed for heavy metals by electrothermal atomic absorption spectrometry (ET-AAS). Pb and Cd were also quantified in the liver fluke Fasciola hepatica as well as in different organs of the large intestinal roundworm Ascaris suum. The levels of these heavy metals in the parasites were compared to those of muscle, liver, kidney and intestine of the respective definitive hosts cattle and swine obtained from a slaughter house. Most parasites accumulated significantly higher levels of metals than their final hosts. This was most conspicuous in acanthocephalans which contained up to 3 {times} 10{sup 3} fold more lead than the muscle of their fish hosts and up to 1.1 {times} 10{sup 4} more lead than the water surrounding the fish. In these helminths cadmium was enriched up to 400 fold compared to the muscle of the fish and up to 2.7 {times} 10{sup 4} compared to the water. In contrast to the accumulation capacity of adult acanthocephalans their larvae contained about 30 to 180 times less Pb and Cd. Thus, the predominant accumulation of both metals appears in the adult worms. The cestodes of fish and the liver flukes of cattle accumulated the metals up to 200 fold compared to the muscle of their hosts. The nematodes did not contain higher levels of the metals than their hosts. Thus, parasites, especially acanthocephalans, seem to be sensitive bioindicators of Pb and Cd in their environments.

High-level Zn and Cd tolerance in Silene paradoxa L. from a moderately Cd- and Zn-contaminated copper mine tailing

International Nuclear Information System (INIS)

Arnetoli, Miluscia; Vooijs, Riet; Gonnelli, Cristina; Gabbrielli, Roberto; Verkleij, Jos A.C.; Schat, Henk

2008-01-01

Cadmium and zinc tolerance were examined in populations of Silene paradoxa, one from uncontaminated calcareous soil (CVD) and one from a mine tailing (FC) (Cd < 1-15 ppm, Zn 400-1300 ppm, pH 2-6). The mine population exhibited extremely high Zn and Cd tolerance levels, although the degrees of Cd and Zn enrichment relatively low at the population site. Cd and Zn hypertolerance in FC were associated with reduced rates of accumulation of these metals, both in roots and shoots (Cd), or exclusively in shoots (Zn). However, exclusion potentially explained only a minor part of the superior tolerance in FC. Cd hypertolerance in FC was associated with decreased, rather than enhanced phytochelatin accumulation. The remarkably high levels of Cd and Zn hypertolerance in FC might relate to the low soil pH, due to oxidation of sulphide minerals, and the absence of soil organic matter at the FC site. - Silene paradoxa from a copper mine exhibits extreme levels of Zn and Cd tolerance

Intraspecific variation in cadmium tolerance and accumulation of a high-biomass tropical tree Averrhoa carambola L.: implication for phytoextraction.

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Dai, Zi-yun; Shu, Wen-sheng; Liao, Bin; Wan, Cai-yun; Li, Jin-tian

2011-06-01

Averrhoa carambola L., a high-biomass tropical tree, has recently been shown to be a strong accumulator of cadmium (Cd) and has great potential for Cd phytoextraction. In the present study, field studies and a controlled-environment experiment were combined to establish the extent of variation in Cd tolerance and accumulation at the cultivar level using 14 to 19 cultivars of A. carambola. The results indicated that all cultivars tested could accumulate Cd at high but different levels, and that Cd tolerance also varied greatly between these cultivars. It is confirmed that the high Cd tolerance and accumulation capacity are species-level and constitutional traits in A. carambola. However, no correlation was detected between tolerance index and accumulation of Cd in different cultivars, suggesting that the two traits are independent in this woody Cd accumulator. More importantly, cultivar Wuchuan Sweet (WCT) was shown to have the highest Cd-extraction potential; it yielded a high shoot biomass of 30 t ha(-1) in 230 d, and extracted 330 g ha(-1) Cd in the aerial tissues grown in Cd-contaminated field soil, which accounted for 12.8% of the total soil Cd in the top 20 cm of the soil profile.

Spatial patterns of heavy metal accumulation in sediments and macrophytes of Bellandur wetland, Bangalore.

Science.gov (United States)

Ramachandra, T V; Sudarshan, P B; Mahesh, M K; Vinay, S

2018-01-15

Heavy metals are one among the toxic chemicals and accumulation in sediments and plants has been posing serious health impacts. Wetlands aid as kidneys of the landscape and help in remediation through uptake of nutrients, heavy metals and other contaminants. The analyses of macrophytes and sediment samples help in evaluating pollution status in aquatic environment. In this study concentration of six heavy metals (Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb) and Zinc (Zn)) were assessed in sediment and dominant macrophyte samples collected from Bellandur Lake, largest Lake of Bangalore, India. Sediment samples reveal of heavy metals in the inlet regions and shore samples. The accumulation of metals in sediments were in the order of Zn > Cu > Cr > Pb > Ni > Cd. All metals exceeded the critical limits of metals in the sediment. Concentration of different metals in the macrophyte samples ranked as: Cr > Cu > Zn > Pb > Ni > Cd. Chromium and Copper were found to be more than critical range. Typha angustata had the higher accumulation of all metals except chromium. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tolerance and accumulation characteristics of cadmium in Amaranthus hybridus L

International Nuclear Information System (INIS)

Zhang Xiaochuan; Zhang Shirong; Xu Xiaoxun; Li Ting; Gong Guoshu; Jia Yongxia; Li Yun; Deng Liangji

2010-01-01

Because of its toxicity to animals and humans, cadmium (Cd) is an environmentally important heavy metal. Consequently, researchers are interested in using hyperaccumulator and accumulator plants to decontaminate Cd polluted soils. To investigate Cd tolerance, uptake and accumulation by Amaranthus hybridus L., Cd concentration gradients were applied to a soil (at rates of 0, 30, 60, 90, 120, 150 and 180 mg kg -1 ) and hydroponics solutions (at rates of 0, 5, 10, 15, 20, 30, and 40 mg L -1 ) following a field survey. A. hybridus grew normally at added Cd concentrations ≤ 90 mg kg -1 and ≤ 20 mg L -1 in the soil culture and in the hydroponics solutions, respectively. In the hydroponics solutions, peroxidase activity showed a quadratic relationship and catalase activity changed irregularly with increasing Cd concentrations. The highest Cd concentration and accumulation in shoots were 241.56 mg kg -1 and 1006.95 μg pot -1 in the soil culture, and 354.56 mg kg -1 and 668.42 μg pot -1 in the hydroponics experiment. Bioconcentration factors in soil culture and hydroponics solutions were 0.58-1.22 and 5.18-17.55, and translocation factors were 0.64-1.50 and 0.33-0.92, respectively. A. hybridus has potential phytoremediation capability in Cd polluted soils.

Tolerance and accumulation characteristics of cadmium in Amaranthus hybridus L

Energy Technology Data Exchange (ETDEWEB)

Zhang Xiaochuan [College of Resources and Environment, Sichuan Agricultural University, 46 Xinkang Road, Yaan 625014 (China); Zhang Shirong, E-mail: rsz01@163.com [College of Resources and Environment, Sichuan Agricultural University, 46 Xinkang Road, Yaan 625014 (China); Xu Xiaoxun; Li Ting [College of Resources and Environment, Sichuan Agricultural University, 46 Xinkang Road, Yaan 625014 (China); Gong Guoshu [Agricultural College, Sichuan Agricultural University, Yaan 625014 (China); Jia Yongxia; Li Yun; Deng Liangji [College of Resources and Environment, Sichuan Agricultural University, 46 Xinkang Road, Yaan 625014 (China)

2010-08-15

Because of its toxicity to animals and humans, cadmium (Cd) is an environmentally important heavy metal. Consequently, researchers are interested in using hyperaccumulator and accumulator plants to decontaminate Cd polluted soils. To investigate Cd tolerance, uptake and accumulation by Amaranthus hybridus L., Cd concentration gradients were applied to a soil (at rates of 0, 30, 60, 90, 120, 150 and 180 mg kg{sup -1}) and hydroponics solutions (at rates of 0, 5, 10, 15, 20, 30, and 40 mg L{sup -1}) following a field survey. A. hybridus grew normally at added Cd concentrations {<=} 90 mg kg{sup -1} and {<=} 20 mg L{sup -1} in the soil culture and in the hydroponics solutions, respectively. In the hydroponics solutions, peroxidase activity showed a quadratic relationship and catalase activity changed irregularly with increasing Cd concentrations. The highest Cd concentration and accumulation in shoots were 241.56 mg kg{sup -1} and 1006.95 {mu}g pot{sup -1} in the soil culture, and 354.56 mg kg{sup -1} and 668.42 {mu}g pot{sup -1} in the hydroponics experiment. Bioconcentration factors in soil culture and hydroponics solutions were 0.58-1.22 and 5.18-17.55, and translocation factors were 0.64-1.50 and 0.33-0.92, respectively. A. hybridus has potential phytoremediation capability in Cd polluted soils.

Irradiation-induced amorphization of Cd2Nb2O7 pyrochlore

International Nuclear Information System (INIS)

Meldrum, A.; White, C. W.; Keppens, V.; Boatner, L. A.; Ewing, R. C.

2001-01-01

Several investigations have recently been undertaken in order to achieve a more complete understanding of the radiation-damage mechanisms in A 2 B 2 O 7 pyrochlore-structure compounds. The present work represents the first systematic study of the irradiation-induced amorphization of a pyrochlore with A- and B-site cation valences of +2 and +5, respectively. Relatively large single crystals of Cd 2 Nb 2 O 7 were grown for these experiments. In situ ion-irradiation experiments were carried out in a transmission electron microscope in conjunction with ex situ Rutherford backscattering measurements of ion-irradiated Cd 2 Nb 2 O 7 single crystals. Cd 2 Nb 2 O 7 can be amorphized in situ by Ne or Xe ions at temperatures up to 480 and 620 K, respectively. At room temperature, the amorphization fluence was 36 times higher for 280 keV Ne + than for 1200 keV Xe 2+ , corresponding to a displacement dose that was higher by a factor of 3. Disordering of Cd and Nb over the available cation sites occurs at intermediate ion doses prior to amorphization. The temperature dependence of the amorphization dose is modeled, and the results are compared to those of a previous model. The bulk-sample Rutherford backscattering spectroscopy (RBS) results were generally consistent with the in situ TEM measurements. Effects of crystallographic orientation and ion charge state had relatively little effect on the damage accumulation in bulk crystals. The RBS data are consistent with a defect-accumulation, cascade-overlap model of amorphization of Cd 2 Nb 2 O 7 , as are the in situ TEM observations

Cadmium accumulation characteristics of low-cadmium rice (Oryza sativa L.) line and F1 hybrids grown in cadmium-contaminated soils.

Science.gov (United States)

Li, Kun; Yu, Haiying; Li, Tingxuan; Chen, Guangdeng; Huang, Fu

2017-07-01

Cadmium (Cd) pollution has threatened severely to food safety and human health. A pot experiment and a field experiment were conducted to investigate the difference of Cd accumulation between rice (Oryza sativa L.) lines and F 1 hybrids in Cd-contaminated soils. The adverse effect on biomass of rice lines was greater than that of F 1 hybrids under Cd treatments in the pot experiment. The variations of Cd concentration among rice cultivars in different organs were smaller in stem and leaf, but larger in root and ear. Average proportion of Cd in root of F 1 hybrids was 1.39, 1.39, and 1.16 times higher than those of rice lines at the treatment of 1, 2, and 4 mg Cd kg -1 soil, respectively. Cd concentrations in ear of F 1 hybrids were significantly lower than rice lines with the reduction from 29.24 to 50.59%. Cd concentrations in brown rice of all F 1 hybrids were less than 0.2 mg kg -1 at 1 mg Cd kg -1 soil, in which Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be screened out as cadmium-safe cultivars (CSCs) for being safe even at 2 mg Cd kg -1 soil. C268A/YaHui2816 showed the lowest Cd concentration in root among F 1 hybrids, while Lu98A/YaHui2816 and 5406A/YaHui2816 showed lower capability of Cd translocation from root to shoot under Cd exposure, which eventually caused the lower Cd accumulation in brown rice. The lower level of Cd translocation contributed to reducing the accumulation of Cd in brown rice had been validated by the field experiment. Thus, Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be considered as potential CSCs to cultivate in Cd-contaminated soils (<2 mg Cd kg -1 soil).

Cadmium toxicity affects chlorophyll a and b content, antioxidant enzyme activities and mineral nutrient accumulation in strawberry

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Ferhad Muradoglu

2015-01-01

Full Text Available BACKGROUND: Cadmium (Cd is well known as one of the most toxic metals affecting the environment and can severely restrict plant growth and development. In this study, Cd toxicities were studied in strawberry cv. Camarosa using pot experiment. Chlorophyll and malondialdehyde (MDA contents, catalase (CAT, superoxide dismutase (SOD, ascorbate peroxidase (APX activities and mineral nutrient concentrations were investigated in both roots and leaves of strawberry plant after exposure Cd. RESULTS: Cd content in both roots and leaves was increased with the application of increasing concentrations of Cd. We found higher Cd concentration in roots rather than in leaves. Chlorophyll a and b was decreased in leaves but MDA significantly increased under increased Cd concentration treatments in both roots and leaves. SOD and CAT activities was also increased with the increase Cd concentrations. K, Mn and Mg concentrations were found higher in leaves than roots under Cd stress. In general, increased Cd treatments increased K, Mg, Fe, Ca, Cu and Zn concentration in both roots and leaves. Excessive Cd treatments reduced chlorophyll contents, increased antioxidant enzyme activities and changes in plant nutrition concentrations in both roots and leaves. CONCLUSION: The results presented in this work suggested that Cd treatments have negative effect on chlorophyll content and nearly decreased 30% of plant growth in strawberry. Strawberry roots accumulated higher Cd than leaves. We found that MDA and antioxidant enzyme (CAT, SOD and APX contents may have considered a good indicator in determining Cd tolerance in strawberry plant.

Cadmium-induced physiological response and antioxidant enzyme changes in the novel cadmium accumulator, Tagetes patula

Energy Technology Data Exchange (ETDEWEB)

Liu, Yu-Ting; Chen, Zueng-Sang [Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan (China); Hong, Chwan-Yang, E-mail: cyhong@ntu.edu.tw [Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan (China)

2011-05-30

The accumulation and effect of cadmium (Cd) on the growth and enzymatic activities changes of antioxidants in Tagetes patula, French marigold, were investigated to reveal the physiological mechanisms corresponding to its Cd tolerance and accumulation. Hydroponically grown T. patula plants were treated with different concentrations of Cd (0, 10, 25, 50 {mu}M CdCl{sub 2}) at various regime of times. T. patula accumulated Cd to a maximum of 450 mg Cd kg{sup -1} dry weight (DW) in shoot and 3500 mg Cd kg{sup -1} DW in root after 14 days' exposure at 10 and 50 {mu}M CdCl{sub 2}, respectively. The translocation factors of Cd were greater than 1 in plants exposed to 10 {mu}M CdCl{sub 2}. Toxic effects were gradually observed with increasing Cd concentration (25 and 50 {mu}M) accompanied with the reduction of biomass, chlorophyll content, decrease of cell viability and the increase level of lipid peroxidation. In leaves of T. patula, the activities of ascorbate peroxidase (APX), glutathione reductase (GR) and superoxide dismutase (SOD) were induced by Cd. However, in roots, activities of APX, GR, SOD and catalase (CAT) were significantly reduced by 25 and 50 {mu}M Cd treatment but not 10 {mu}M Cd. In-gel zymography analysis revealed that Cd induced the enzymatic activities of APX, MnSOD, CuZnSOD and different isozymes of GR in leaves. These results indicate that T. patula is a novel Cd accumulator and able to tolerate with Cd-induced toxicity by activation of its antioxidative defense system.

Cadmium-induced physiological response and antioxidant enzyme changes in the novel cadmium accumulator, Tagetes patula

International Nuclear Information System (INIS)

Liu, Yu-Ting; Chen, Zueng-Sang; Hong, Chwan-Yang

2011-01-01

The accumulation and effect of cadmium (Cd) on the growth and enzymatic activities changes of antioxidants in Tagetes patula, French marigold, were investigated to reveal the physiological mechanisms corresponding to its Cd tolerance and accumulation. Hydroponically grown T. patula plants were treated with different concentrations of Cd (0, 10, 25, 50 μM CdCl 2 ) at various regime of times. T. patula accumulated Cd to a maximum of 450 mg Cd kg -1 dry weight (DW) in shoot and 3500 mg Cd kg -1 DW in root after 14 days' exposure at 10 and 50 μM CdCl 2 , respectively. The translocation factors of Cd were greater than 1 in plants exposed to 10 μM CdCl 2 . Toxic effects were gradually observed with increasing Cd concentration (25 and 50 μM) accompanied with the reduction of biomass, chlorophyll content, decrease of cell viability and the increase level of lipid peroxidation. In leaves of T. patula, the activities of ascorbate peroxidase (APX), glutathione reductase (GR) and superoxide dismutase (SOD) were induced by Cd. However, in roots, activities of APX, GR, SOD and catalase (CAT) were significantly reduced by 25 and 50 μM Cd treatment but not 10 μM Cd. In-gel zymography analysis revealed that Cd induced the enzymatic activities of APX, MnSOD, CuZnSOD and different isozymes of GR in leaves. These results indicate that T. patula is a novel Cd accumulator and able to tolerate with Cd-induced toxicity by activation of its antioxidative defense system.

Characterization of cadmium-resistant bacteria and their potential for reducing accumulation of cadmium in rice grains.

Science.gov (United States)

Lin, Xiaoyan; Mou, Renxiang; Cao, Zhaoyun; Xu, Ping; Wu, Xiaoliang; Zhu, Zhiwei; Chen, Mingxue

2016-11-01

Cadmium (Cd) pollution is a serious widespread environmental problem that not only destroys the microbial ecology of soil and decreases crop production, but also poses a serious risk to human health. Many methods have been used for the remediation of Cd pollution but none of these is totally satisfactory. Microbial remediation strategies have attracted increasing interest since they are environmentally friendly and cost-effective. In the present study, three Cd-resistant bacteria were isolated and evaluated for potential application in Cd bioremediation. Based on their morphological, physiological and biochemical characteristics, together with 16S rDNA gene sequence analyses, bacteria were identified as Stenotrophomonas acidaminiphila (2#), Pseudomonas aeruginosa (9#) and Delftia tsuruhatensis (12#). Pseudomonas aeruginosa showed very high tolerance to metals, especially Cd (2200mg/L), Zn (1800mg/L) and Pb (1200mg/L), and is thought to be a multi-metal-resistant bacterium. Pseudomonas aeruginosa was also sensitive to 13 different antibiotics. The effects of the bacterial strains on the growth of rice plants and their ability to reduce Cd accumulation from Cd-contaminated soils in pot experiments were also evaluated. For Oryza sativa L. A grown in contaminated soil (3mg/kg Cd), the accumulation of Cd was decreased by 31.2 and 25.5% in brown rice and polished rice, respectively, by strain 9#; Pseudomonas aeruginosa was more effective in reducing Cd accumulation in rice grains than a mixture of strains. For Oryza sativa L. B, a mixture of strains acting synergistically was more effective than a single strain in reducing Cd accumulation; treatment with mixed strains (strains+3mg/kg Cd) resulted in 41.3, 35.9, and 32.6% reductions in Cd accumulation in unhulled rice, brown rice and polished rice, respectively. Although different results were obtained for two rice varieties, it can still be concluded that Cd-resistant bacteria are suitable for reducing Cd accumulation in

Heavy metal accumulation by poplar in calcareous soil with various degrees of multi-metal contamination: implications for phytoextraction and phytostabilization.

Science.gov (United States)

Hu, Yahu; Nan, Zhongren; Su, Jieqiong; Wang, Ning

2013-10-01

The object of this study was to assess the capacity of Populus alba L. var. pyramidalis Bunge for phytoremediation of heavy metals on calcareous soils contaminated with multiple metals. In a pot culture experiment, a multi-metal-contaminated calcareous soil was mixed at different ratios with an uncontaminated, but otherwise similar soil, to establish a gradient of soil metal contamination levels. In a field experiment, poplars with different stand ages (3, 5, and 7 years) were sampled randomly in a wastewater-irrigated field. The concentrations of cadmium (Cd), Cu, lead (Pb), and zinc (Zn) in the poplar tissues and soil were determined. The accumulation of Cd and Zn was greatest in the leaves of P. pyramidalis, while Cu and Pb mainly accumulated in the roots. In the pot experiment, the highest tissue concentrations of Cd (40.76 mg kg(-1)), Cu (8.21 mg kg(-1)), Pb (41.62 mg kg(-1)), and Zn (696 mg kg(-1)) were all noted in the multi-metal-contaminated soil. Although extremely high levels of Cd and Zn accumulated in the leaves, phytoextraction using P. pyramidalis may take at least 24 and 16 years for Cd and Zn, respectively. The foliar concentrations of Cu and Pb were always within the normal ranges and were never higher than 8 and 5 mg kg(-1), respectively. The field experiment also revealed that the concentrations of all four metals in the bark were significantly higher than that in the wood. In addition, the tissue metal concentrations, together with the NH4NO3-extractable concentrations of metals in the root zone, decreased as the stand age increased. P. pyramidalis is suitable for phytostabilization of calcareous soils contaminated with multiple metals, but collection of the litter fall would be necessary due to the relatively high foliar concentrations of Cd and Zn.

Trophic transfer of Cd from duckweed (Lemna minor L.) to tilapia (Oreochromis mossambicus).

Science.gov (United States)

Xue, Yan; Peijnenburg, Willie J G M; Huang, Jin; Wang, Dengjun; Jin, Yan

2018-05-01

The transfer of the toxic heavy metal Cd from duckweed (Lemna minor L.) to the freshwater fish tilapia (Oreochromis mossambicus) was investigated. Concentrations of Cd in different chemical forms in duckweed and in different tissues (gut, edible muscle, and remnants or residual) of tilapia (i.e., ethanol-extractable fraction [F E ], HCl-extractable fraction [F HCl ], and residual fraction [F R ]) were quantified, and the bioaccumulation factors (BAFs) of Cd in the tilapia body were calculated. Simple linear regression analysis was used to unravel the correlation and accumulation mechanisms of Cd along the short food chain. Our results showed that with increasing exposure concentrations of Cd (0-50 μM for duckweed and 0-10 μM for tilapia), the total, F E (F e,d )-, F HCl (F h,d )-, and F R (F r,d )-Cd concentrations in duckweed and different tissues of tilapia increased progressively. The Cd sources (aqueous or dietary) influenced the BAF for Cd accumulation in the whole body of tilapia. Furthermore, regression analyses yielded significant positive correlations (R 2 > 0.96) between the Cd concentration in duckweed and in both the 3 parts and the whole body of tilapia. This finding suggests that Cd transfer from duckweed to tilapia can be quantitatively evaluated when tilapia is exposed only to duckweed. In addition, the linear regression between Cd accumulation in whole tilapia and F e,d -, F h,d -, and F r,d -Cd showed that particularly the correlation with F e,d -Cd is statistically significant (p < 0.001). The accumulated Cd concentrations and chemical forms in tilapia tissues also positively correlated with Cd sources (solution or duckweed). Compared with waterborne exposure only, duckweed especially increased the accumulation of Cd in the gut of tilapia. Taken together, our findings support a strong dependence of Cd accumulation and transfer from duckweed to tilapia on its chemical forms, especially on F e,d -Cd. This knowledge may expedite more

Combined nitrogen limitation and cadmium stress stimulate total carbohydrates, lipids, protein and amino acid accumulation in Chlorella vulgaris (Trebouxiophyceae)

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Chia, Mathias Ahii, E-mail: chia28us@yahoo.com [Department of Botany, Federal University of São Carlos, Rodovia Washington Luis km 235, São Carlos, SP Cep 13565905 (Brazil); Lombardi, Ana Teresa [Department of Botany, Federal University of São Carlos, Rodovia Washington Luis km 235, São Carlos, SP Cep 13565905 (Brazil); Graça Gama Melão, Maria da [Department of Hydrobiology, Federal University of São Carlos, Rodovia Washington Luis km 235, São Carlos, SP Cep 13565905 (Brazil); Parrish, Christopher C. [Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, Newfoundland A1C 5S7 (Canada)

2015-03-15

Highlights: • Chlorella vulgaris was exposed to Cd under varying N concentrations. • Growth rate and cell density decreased with increasing Cd stress and N limitation. • Dry weight, chlorophyll a, total lipid, carbohydrate and protein were accumulated. • Amino acids like proline and glutamine were accumulated under N and Cd stress. • Changes in amino acid composition are sensitive biomarkers for Cd and N stress. - Abstract: Metals have interactive effects on the uptake and metabolism of nutrients in microalgae. However, the effect of trace metal toxicity on amino acid composition of Chlorella vulgaris as a function of varying nitrogen concentrations is not known. In this research, C. vulgaris was used to investigate the influence of cadmium (10{sup −7} and 2.0 × 10{sup −8} mol L{sup −1} Cd) under varying nitrogen (2.9 × 10{sup −6}, 1.1 × 10{sup −5} and 1.1 × 10{sup −3} mol L{sup −1} N) concentrations on its growth rate, biomass and biochemical composition. Total carbohydrates, total proteins, total lipids, as well as individual amino acid proportions were determined. The combination of Cd stress and N limitation significantly inhibited growth rate and cell density of C. vulgaris. However, increasing N limitation and Cd stress stimulated higher dry weight and chlorophyll a production per cell. Furthermore, biomolecules like total proteins, carbohydrates and lipids increased with increasing N limitation and Cd stress. Ketogenic and glucogenic amino acids were accumulated under the stress conditions investigated in the present study. Amino acids involved in metal chelation like proline, histidine and glutamine were significantly increased after exposure to combined Cd stress and N limitation. We conclude that N limitation and Cd stress affects the physiology of C. vulgaris by not only decreasing its growth but also stimulating biomolecule production.

Comparative proteomic analysis provides new insights into cadmium accumulation in rice grain under cadmium stress

Energy Technology Data Exchange (ETDEWEB)

Xue, Dawei, E-mail: dwxue@hznu.edu.cn [College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036 (China); State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006 (China); Jiang, Hua [State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Science, Hangzhou 310021 (China); Deng, Xiangxiong; Zhang, Xiaoqin [College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036 (China); Wang, Hua [State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Science, Hangzhou 310021 (China); Xu, Xiangbin [College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036 (China); Hu, Jiang; Zeng, Dali [State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006 (China); Guo, Longbiao, E-mail: guolongbiao@caas.cn [State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006 (China); Qian, Qian, E-mail: qianqian188@hotmail.com [College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036 (China); State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006 (China)

2014-09-15

Graphical abstract: - Highlights: • Cd is the most toxic heavy metal and is a major pollutant in rice grains. • The mechanism of Cd accumulation in rice grains has not been well demonstrated. • Proteomics analysis is carried out and the verification is implemented by QPCR. • Proteins associated with ROS and photosynthesis showed large variation in expression. - Abstract: Rice is one of the most important staple crops. During the growth season, rice plants are inevitably subjected to numerous stresses, among which heavy metal stress represented by cadmium contamination not only hindering the yield of rice but also affecting the food safety by Cd accumulating in rice grains. The mechanism of Cd accumulation in rice grains has not been well elucidated. In this study, we compare the proteomic difference between two genotypes with different Cd accumulation ability in grains. Verification of differentially expressed protein-encoding genes was analyzing by quantitative PCR (QPCR) and reanalysis of microarray expression data. Forty-seven proteins in total were successfully identified through proteomic screening. GO and KEGG enrichment analysis showed Cd accumulation triggered stress-related pathways in the cells, and strongly affecting metabolic pathways. Many proteins associated with nutrient reservoir and starch-related enzyme were identified in this study suggesting that a considerably damage on grain quality was caused. The results also implied stress response was initiated by the abnormal cells and the transmission of signals may mediated by reactive oxygen species (ROS). Our research will provide new insights into Cd accumulation in rice grain under Cd stress.

Identification of rice cultivar with exclusive characteristic to Cd using a field-polluted soil and its foreground application.

Science.gov (United States)

Zhan, Jie; Wei, Shuhe; Niu, Rongcheng; Li, Yunmeng; Wang, Shanshan; Zhu, Jiangong

2013-04-01

Using low-accumulative plant, especially excluder crop, to safely produce food is one of the very important technologies of phytoremediation, which is practical to safe production and long-term remediation of heavy metal-contaminated soil. A pot experiment using field cadmium (Cd)-contaminated soil (Cd concentration was 0.75 mg kg(-1)) was conducted to compare Cd accumulation differences among 39 normal rice cultivars (Japonica) in Shenyang region of China for food safety and high grain yield aim. The results showed that brown grain Cd concentration in 12 rice cultivars of a total of 39 tested cultivars was lower than 0.2 mg kg(-1) (Agricultural Trade Standard of Nonpollution Food for Rice of China, NY 5115-2008). In these 12 cultivars, Cd enrichment factors (Cd concentration ratio in shoot to that in soil) of nine cultivars were lower than 1. Likewise, Cd translocation factors (Cd concentration ratio in shoot to that in root) of eight cultivars were lower than the 0.28 average. Furthermore, grain yield per pot of seven cultivars were higher than the average 18.4 g pot(-1). Four cultivars, i.e., Shendao 5, Tianfu 1, Fuhe 90, and Yanfeng 47 showed Cd-exclusive characteristic and better foreground application.

Is oxidative stress related to cadmium accumulation in the Mollusc Crassostrea angulata?

Science.gov (United States)

Macías-Mayorga, Dayanara; Laiz, Irene; Moreno-Garrido, Ignacio; Blasco, Julián

2015-04-01

The kinetics of cadmium (Cd) accumulation in the gills and digestive gland of Crassotrea angulata at three concentrations of cadmium (0.088 μM, 0.44 μM and 2.22 μM) was monitored for 28 days. The relationship between accumulation and toxicity was studied using metallothionein-like protein (MTLP) concentration and reduced glutathione levels (GSH) as biochemical endpoints. The activity of enzymes which form part of the antioxidant defense system, in particular glutathione reductase (GR), total glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT), as enzymatic endpoints, was also assessed. A first order kinetic model demonstrated that the accumulation process does not take place linearly, as the Cd concentration in gills and digestive gland tended toward a stationary state. Metallothionein-like protein is clearly induced by Cd accumulation; however, at high Cd concentrations the detoxification mechanism of this protein is affected. High Cd concentrations (2.22 μM) lead to a decrease in GSH levels, and also inhibit antioxidant enzyme activities, demonstrating the adverse effect of this metal on the antioxidant balance system. Copyright © 2015 Elsevier B.V. All rights reserved.

Copper changes the yield and cadmium/zinc accumulation and cellular distribution in the cadmium/zinc hyperaccumulator Sedum plumbizincicola

Energy Technology Data Exchange (ETDEWEB)

Li, Zhu [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); University of the Chinese Academy of Sciences, Beijing 100049 (China); Wu, Longhua, E-mail: lhwu@issas.ac.cn [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Hu, Pengjie [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Luo, Yongming [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Yantai Institute of Coastal Zone Research, Yantai 264003 (China); Christie, Peter [Agri-Environment Branch, Agri-Food and Biosciences Institute, Newforge Lane, Belfast BT9 5PX (United Kingdom)

2013-10-15

Highlights: • Low Cu has no significant effect on Sedum plumbizincicola plant growth and Cd and Zn uptake. • Plant held Cu in unactive areas and insoluble forms as de-toxification mechanisms. • Influence of Cu on Zn and Cd uptake and translocation were different. • Cu accumulation in leaf veins may restrain Cd/Zn unloading to the leaves -- Abstract: Non-accumulated metals in mixed metal contaminated soils may affect hyperaccumulator growth and metal accumulation and thus remediation efficiency. Two hydroponics experiments were conducted to investigate the effects of copper (Cu) on cadmium (Cd) and zinc (Zn) accumulation by the Cd/Zn hyperaccumulator Sedum plumbizincicola, Cu toxicity and plant detoxification using chemical sequential extraction of metals, sub-cellular separation, micro synchrotron radiation based X-ray fluorescence, and transmission electron microscopy. Compared with the control (0.31 μM Cu), 5–50 μM Cu had no significant effect on Cd/Zn accumulation, but Cu at 200 μM induced root cell plasmolysis and disordered chloroplast structure. The plants held Cu in the roots and cell walls and complexed Cu in insoluble forms as their main detoxification mechanisms. Exposure to 200 μM Cu for 4 days inhibited plant Cd uptake and translocation but did not affect Zn concentrations in roots and stems. Moreover, unloading of Cd and Zn from stem to leaf was restrained compared to control plants, perhaps due to Cu accumulation in leaf veins. Copper may thus interfere with root Cd uptake and restrain Cd/Zn unloading to the leaves. Further investigation of how Cu affects plant metal uptake may help elucidate the Cd/Zn hyper-accumulating mechanisms of S. plumbizincicola.

Copper changes the yield and cadmium/zinc accumulation and cellular distribution in the cadmium/zinc hyperaccumulator Sedum plumbizincicola

International Nuclear Information System (INIS)

Li, Zhu; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Christie, Peter

2013-01-01

Highlights: • Low Cu has no significant effect on Sedum plumbizincicola plant growth and Cd and Zn uptake. • Plant held Cu in unactive areas and insoluble forms as de-toxification mechanisms. • Influence of Cu on Zn and Cd uptake and translocation were different. • Cu accumulation in leaf veins may restrain Cd/Zn unloading to the leaves -- Abstract: Non-accumulated metals in mixed metal contaminated soils may affect hyperaccumulator growth and metal accumulation and thus remediation efficiency. Two hydroponics experiments were conducted to investigate the effects of copper (Cu) on cadmium (Cd) and zinc (Zn) accumulation by the Cd/Zn hyperaccumulator Sedum plumbizincicola, Cu toxicity and plant detoxification using chemical sequential extraction of metals, sub-cellular separation, micro synchrotron radiation based X-ray fluorescence, and transmission electron microscopy. Compared with the control (0.31 μM Cu), 5–50 μM Cu had no significant effect on Cd/Zn accumulation, but Cu at 200 μM induced root cell plasmolysis and disordered chloroplast structure. The plants held Cu in the roots and cell walls and complexed Cu in insoluble forms as their main detoxification mechanisms. Exposure to 200 μM Cu for 4 days inhibited plant Cd uptake and translocation but did not affect Zn concentrations in roots and stems. Moreover, unloading of Cd and Zn from stem to leaf was restrained compared to control plants, perhaps due to Cu accumulation in leaf veins. Copper may thus interfere with root Cd uptake and restrain Cd/Zn unloading to the leaves. Further investigation of how Cu affects plant metal uptake may help elucidate the Cd/Zn hyper-accumulating mechanisms of S. plumbizincicola

Study of Te Inclusions in CdMnTe Crystals for Nuclear Detector Applications

International Nuclear Information System (INIS)

Babalola, O.S.; Bolotnikov, A.; Groza, M.; Hossain, A.; Egarievwe, S.; James, R.; Burger, A.

2009-01-01

The concentration, size and spatial distribution of Te inclusions in the bulk of CdMnTe crystals mined from two batches of ingots were studied. An isolated planar layer decorated with Te inclusions was identified in CdMnTe crystals from the second ingot. The internal electric field of a CMT crystal was probed by infrared (IR) imaging employing Pockels electro-optic effect. The effect of an isolated plane of Te inclusions on the internal electric-field distribution within the CdMnTe crystal was studied. Space charge accumulation around the plane of Te inclusions was observed, which was found to be higher when the detector was reverse-biased. The effects of the plane of Te inclusions on the electric-field distribution within the CdMnTe crystal, and the quality of CdMnTe crystals for nuclear detector applications are discussed.

Bioaccumulation of toxic metals (Cd and Cu) by Groenlandia densa (L.) Fourr.

Science.gov (United States)

Kara, Yesim; Zeytunluoglu, Ali

2007-12-01

In this study, Groenlandia densa (L.) Fourr. (opposite-leaved pondweed), was exposed to prepared stock solution of cadmium and copper with 1.0, 3.0, 5.0 and 7.0 mg L(-1) concentration in certain periods (24, 48, 72 and 96 h) and changing amount of accumulation of plants in depending on time and concentration was measured by atomic absorption spectrophotometer. The results show that under experimental conditions, G. densa (L.) Fourr. proved to be a good accumulator of Cd and Cu. Removal of the metals from solution was fast in the first 4 days. The accumulation of Cd and Cu increased with the initial concentration and also with time. The highest concentrations of each trace element accumulated in opposite-leaved pondweed tissues were 1,955 mug Cd g(-1), 6,135 microg Cu g(-1) after 4 days. The maximum values of bioconcentration factor (BCF) were found for Cd and Cu 724 and 1,669, respectively. BCF values for Cd and Cu increased with time.

Analysis of heavy metal accumulation in fish from the coastal waters of Terengganu, Malaysia

Science.gov (United States)

Rosli, M. N. R.; Samat, S. B.; Yasir, M. S.

2018-04-01

Bioaccumulation of toxic metals in fish causes serious threats to the human when they are consumed. Thus, the detection of toxic element concentration levels in fish is important. The accumulation of four heavy metal concentration of Cd, Cu, Mn and Zn in fish was determined. Five fish species namely Epinephelus lanceolatus, Rastrelliger, Megalaspis cordyla, Bramidae and Siganus canaliculatus were collected from the coastal waters of Terengganu, Malaysia. The analysis was done using inductive coupled plasma-mass spectrometer (ICP-MS) technique. The accumulation of the four heavy metals in muscle tissues of the fish are lower compared to liver and gill tissues. Cd concentration was higher in liver tissues except in Megalaspis cordyla. Meanwhile Cu concentration was higher in liver for all selected fishes. Mn concentration was higher in gill tissues of all fish studied while Zn concentration was higher in gill tissues except in Epinephelus lanceolatus and Rastrelliger. The highest average level of heavy metal recorded in fish is Zn (11.05 × 10-2 ± 1.44 × 10-2 mg kg-1) followed by Mn (1.81 × 10-2 ± 0.58 × 10-2 mg kg-1), Cu (0.70 × 10-2 ± 0.10 × 10-2 mg kg-1) and Cd (0.52×10-2 ± 0.27 × 10-2 mg kg-1). The metal concentration found in this study was lower than the national and international Recommended Dietary Allowance (RDA) for human consumption. Long term monitoring system of metal bioaccumulation in fishes need to be done to provide useful information for the assessment of the potential health risks of metals in Malaysia.

Higher transcription levels in ascorbic acid biosynthetic and recycling genes were associated with higher ascorbic acid accumulation in blueberry.

Science.gov (United States)

Liu, Fenghong; Wang, Lei; Gu, Liang; Zhao, Wei; Su, Hongyan; Cheng, Xianhao

2015-12-01

In our preliminary study, the ripe fruits of two highbush blueberry (Vaccinium corymbosum L.) cultivars, cv 'Berkeley' and cv 'Bluecrop', were found to contain different levels of ascorbic acid. However, factors responsible for these differences are still unknown. In the present study, ascorbic acid content in fruits was compared with expression profiles of ascorbic acid biosynthetic and recycling genes between 'Bluecrop' and 'Berkeley' cultivars. The results indicated that the l-galactose pathway was the predominant route of ascorbic acid biosynthesis in blueberry fruits. Moreover, higher expression levels of the ascorbic acid biosynthetic genes GME, GGP, and GLDH, as well as the recycling genes MDHAR and DHAR, were associated with higher ascorbic acid content in 'Bluecrop' compared with 'Berkeley', which indicated that a higher efficiency ascorbic acid biosynthesis and regeneration was likely to be responsible for the higher ascorbic acid accumulation in 'Bluecrop'. Copyright © 2015 Elsevier Ltd. All rights reserved.

Accumulation and localization of cadmium in Echinochloa polystachya grown within a hydroponic system

Energy Technology Data Exchange (ETDEWEB)

Solis-Dominguez, F.A. [CINVESTAV-IPN, Dpto. de Biotecnologia y Bioingenieria, Av. Instituto Politecnico Nacional No. 2508, 07360 Mexico, D.F. (Mexico); Gonzalez-Chavez, M.C. [Colegio de Postgraduados en Ciencias Agricolas, IRENAT, Carr. Mex-Texcoco km 36.5, Montecillo, Estado de Mexico 56230 (Mexico); Carrillo-Gonzalez, R. [Colegio de Postgraduados en Ciencias Agricolas, IRENAT, Carr. Mex-Texcoco km 36.5, Montecillo, Estado de Mexico 56230 (Mexico); Rodriguez-Vazquez, R. [CINVESTAV-IPN, Dpto. de Biotecnologia y Bioingenieria, Av. Instituto Politecnico Nacional No. 2508, 07360 Mexico, D.F. (Mexico)]. E-mail: rerovaz@yahoo.com.mx

2007-03-22

Phytoremediation is a technology for extracting or inactivating pollutants. Echinochloa polystachya [(H.B.K.) Hitchcock] (Poaceae) is a fast-growing perennial grass that is common in tropical areas and is often found in oil-polluted soils that contain high concentrations of heavy metals. However, its tolerance to heavy metals, and its ability to accumulate them, has yet to be investigated. Here we test the hypothesis that E. polystachya is able to accumulate high concentrations of cadmium (Cd). Plants were grown hydroponically with different levels of Cd{sup 2+} (0, 0.25, 1, 2, 10, 50, and 100 mg L{sup -1}), and were found to be tolerant to Cd{sup 2+} at all levels. No metal-toxicity symptoms were observed at any Cd{sup 2+} level. Root and leaves Cd concentrations were 299 {+-} 13.93 and 233 {+-} 8.77 mg kg{sup -1} (on a dry weight basis), respectively. Scanning electron microscopy showed the inclusion of Cd within the xylem; this result was confirmed by energy dispersive X-ray spectrometry. Leaf tissues also accumulated Cd, especially within the bulliform cells of the epidermis. We conclude that E. polystachya is a hyperaccumulator of Cd. While data for other metals are not yet available, E. polystachya shows promise in the phytoextraction of Cd from polluted tropical sites.

Accumulation and localization of cadmium in Echinochloa polystachya grown within a hydroponic system

International Nuclear Information System (INIS)

Solis-Dominguez, F.A.; Gonzalez-Chavez, M.C.; Carrillo-Gonzalez, R.; Rodriguez-Vazquez, R.

2007-01-01

Phytoremediation is a technology for extracting or inactivating pollutants. Echinochloa polystachya [(H.B.K.) Hitchcock] (Poaceae) is a fast-growing perennial grass that is common in tropical areas and is often found in oil-polluted soils that contain high concentrations of heavy metals. However, its tolerance to heavy metals, and its ability to accumulate them, has yet to be investigated. Here we test the hypothesis that E. polystachya is able to accumulate high concentrations of cadmium (Cd). Plants were grown hydroponically with different levels of Cd 2+ (0, 0.25, 1, 2, 10, 50, and 100 mg L -1 ), and were found to be tolerant to Cd 2+ at all levels. No metal-toxicity symptoms were observed at any Cd 2+ level. Root and leaves Cd concentrations were 299 ± 13.93 and 233 ± 8.77 mg kg -1 (on a dry weight basis), respectively. Scanning electron microscopy showed the inclusion of Cd within the xylem; this result was confirmed by energy dispersive X-ray spectrometry. Leaf tissues also accumulated Cd, especially within the bulliform cells of the epidermis. We conclude that E. polystachya is a hyperaccumulator of Cd. While data for other metals are not yet available, E. polystachya shows promise in the phytoextraction of Cd from polluted tropical sites

Cadmium (Cd) Localization in Tissues of Cotton (Gossypium hirsutum L.), and Its Phytoremediation Potential for Cd-Contaminated Soils.

Science.gov (United States)

Chen, Zhifan; Zhao, Ye; Fan, Lidong; Xing, Liteng; Yang, Yujie

2015-12-01

Phytoremediation using economically valuable, large biomass, non-edible plants is a promising method for metal-contaminated soils. This study investigated cotton's tolerance for Cd and remediation potential through analyzing Cd bioaccumulation and localization in plant organs under different soil Cd levels. Results showed cotton presents good tolerance when soil Cd concentration ≤20.26 mg kg(-1). Cotton had good Cd accumulation ability under low soil Cd levels (soil Cd, while roots and stems were the main compartments of Cd storage. Cd complexation to other organic constituents in root and stem cell sap could be a primary detoxifying strategy. Therefore, cotton is a potential candidate for phytoremediation of Cd-contaminated soils.

A higher risk of acute rejection of human kidney allografts can be predicted from the level of CD45RC expressed by the recipients' CD8 T cells.

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Laurence Ordonez

Full Text Available Although transplantation is the common treatment for end-stage renal failure, allograft rejection and marked morbidity from the use of immunosuppressive drugs remain important limitations. A major challenge in the field is to identify easy, reliable and noninvasive biomarkers allowing the prediction of deleterious alloreactive immune responses and the tailoring of immunosuppressive therapy in individuals according to the rejection risk. In this study, we first established that the expression of the RC isoform of the CD45 molecule (CD45RC on CD4 and CD8 T cells from healthy individuals identifies functionally distinct alloreactive T cell subsets that behave differently in terms of proliferation and cytokine secretion. We then investigated whether the frequency of the recipients CD45RC T cell subsets before transplantation would predict acute graft rejection in a cohort of 89 patients who had undergone their first kidney transplantation. We showed that patients exhibiting more than 54.7% of CD8 CD45RC(high T cells before transplantation had a 6 fold increased risk of acute kidney graft rejection. In contrast, the proportions of CD4 CD45RC T cells were not predictive. Thus, a higher risk of acute rejection of human kidney allografts can be predicted from the level of CD45RC expressed by the recipients' CD8 T cells.

The accumulation of elements in plants growing spontaneously on small heaps left by the historical Zn-Pb ore mining.

Science.gov (United States)

Stefanowicz, Anna M; Stanek, Małgorzata; Woch, Marcin W; Kapusta, Paweł

2016-04-01

The study evaluated the levels of nine metals, namely Ca, Cd, Fe, K, Mg, Mn, Pb, Tl, and Zn, in soils and tissues of ten plant species growing spontaneously on heaps left by historical mining for Zn-Pb ores. The concentrations of Cd, Pb, Tl, and Zn in heap soils were much higher than in control soils. Plants growing on heaps accumulated excessive amounts of these elements in tissues, on average 1.3-52 mg Cd kg(-1), 9.4-254 mg Pb kg(-1), 0.06-23 mg Tl kg(-1) and 134-1479 mg Zn kg(-1) in comparison to 0.5-1.1 mg Cd kg(-1), 2.1-11 mg Pb kg(-1), 0.02-0.06 mg Tl kg(-1), and 23-124 mg Zn kg(-1) in control plants. The highest concentrations of Cd, Pb, and Zn were found in the roots of Euphorbia cyparissias, Fragaria vesca, and Potentilla arenaria, and Tl in Plantago lanceolata. Many species growing on heaps were enriched in K and Mg, and depleted in Ca, Fe, and Mn. The concentrations of all elements in plant tissues were dependent on species, organ (root vs. shoot), and species-organ interactions. Average concentrations of Ca, K, and Mg were generally higher in shoots than in roots or similar in the two organs, whereas Cd, Fe, Pb, Tl, and Zn were accumulated predominantly in the roots. Our results imply that heaps left by historical mining for Zn-Pb ores may pose a potential threat to the environment and human health.

Anthropogenic impact on diffuse trace metal accumulation in river sediments from agricultural reclamation areas with geochemical and isotopic approaches

Energy Technology Data Exchange (ETDEWEB)

Jiao, Wei; Ouyang, Wei, E-mail: wei@itc.nl; Hao, Fanghua; Lin, Chunye

2015-12-01

A better understanding of anthropogenic impact can help assess the diffuse trace metal accumulation in the agricultural environment. In this study, both river sediments and background soils were collected from a case study area in Northeast China and analyzed for total concentrations of six trace metals, four major elements and three lead isotopes. Results showed that Pb, Cd, Cu, Zn, Cr and Ni have accumulated in the river sediments after about 40 years of agricultural development, with average concentrations 1.23–1.71 times higher than local soil background values. Among them Ni, Cr and Cu were of special concern and they may pose adverse biological effects. By calculating enrichment factor (EF), it was found that the trace metal accumulation was still mainly ascribed to natural weathering processes, but anthropogenic contribution could represent up to 40.09% of total sediment content. For Pb, geochemical and isotopic approaches gave very similar anthropogenic contributions. Principal component analysis (PCA) further suggested that the anthropogenic Pb, Cu, Cr and Ni inputs were mostly related to the regional atmospheric deposition of industrial emissions and gasoline combustion, which had a strong affinity for iron oxides in the sediments. Concerning Cd, however, it mainly originated from local fertilizer applications and was controlled by sediment carbonates. - Graphical abstract: The trace metal accumulation was mainly ascribed to natural weathering processes, but anthropogenic contribution could represent up to 40.09% of total sediment content. Anthropogenic Pb, Cu, Cr and Ni mostly came from atmospheric deposition, while fertilizer application was the main anthropogenic source of Cd. - Highlights: • Trace metals have accumulated in the Naolihe sediments. • Natural weathering was still a major contributor to metal accumulation. • Anthropogenic Pb, Cu, Cr and Ni mostly came from atmospheric deposition. • Local fertilizer application was the main

Foliar application with nano-silicon reduced cadmium accumulation in grains by inhibiting cadmium translocation in rice plants.

Science.gov (United States)

Chen, Rui; Zhang, Changbo; Zhao, Yanling; Huang, Yongchun; Liu, Zhongqi

2018-01-01

Nano-silicon (Si) may be more effective than regular fertilizers in protecting plants from cadmium (Cd) stress. A field experiment was conducted to study the effects of nano-Si on Cd accumulation in grains and other organs of rice plants (Oryza sativa L. cv. Xiangzaoxian 45) grown in Cd-contaminated farmland. Foliar application with 5~25 mM nano-Si at anthesis stage reduced Cd concentrations in grains and rachises at maturity stage by 31.6~64.9 and 36.1~60.8%, respectively. Meanwhile, nano-Si application significantly increased concentrations of potassium (K), magnesium (Mg), and iron (Fe) in grains and rachises, but imposed little effect on concentrations of calcium (Ca), zinc (Zn), and manganese (Mn) in them. Uppermost nodes under panicles displayed much higher Cd concentration (4.50~5.53 mg kg -1 ) than other aerial organs. After foliar application with nano-Si, translocation factors (TFs) of Cd ions from the uppermost nodes to rachises significantly declined, but TFs of K, Mg, and Fe from the uppermost nodes to rachises increased significantly. High dose of nano-Si (25 mM) was more effective than low dose of nano-Si in reducing TFs of Cd from roots to the uppermost nodes and from the uppermost nodes to rachises. These findings indicate that nano-Si supply reduces Cd accumulation in grains by inhibiting translocation of Cd and, meanwhile, promoting translocation of K, Mg, and Fe from the uppermost nodes to rachises in rice plants.

A link between lead and cadmium kinetic speciation in seawater and accumulation by the green alga Ulva lactuca

International Nuclear Information System (INIS)

Muse, J.O.; Carducci, C.N.; Stripeikis, J.D.; Tudino, M.B.; Fernandez, F.M.

2006-01-01

In this work, studies on the bioaccumulation of Cd and Pb by Ulva lactuca at different sites of Gulf San Jorge (Patagonia, Argentina) are presented. Higher values of bioaccumulated Cd were found in Punta Maqueda - a site believed to serve as a control - in comparison to those in Punta Borja, a place highly exposed to urban and industrial activities. Consequently; the labile fractions of Cd and Pb in seawater were determined with a flow injection-preconcentration manifold interfaced to a graphite furnace-atomic absorption spectrometer (FI-GFAAS). The results obtained by kinetic speciation showed that the variable that correctly explains heavy metals accumulation in the alga, is the labile metal fraction in seawater. We propose to use an enhancement ratio - on the basis of the kinetically labile metal fraction - for calculation of the metal accumulated by the alga relative to its environment. - Metal kinetic speciation can overcome CF limitations for the evaluation of marine pollution

Study on transportation and accumulation mechanism of cadmium in metal-hyperaccumulating fern, Athyrium yokoscense, by synchrotron radiation x-ray fluorescence analysis

International Nuclear Information System (INIS)

Taoka, Hiroki; Nakai, Izumi; Hokura, Akiko; Goto, Fumiyuki; Yoshihara, Toshihiro; Abe, Tomoko; Terada, Yasuko

2012-01-01

High energy synchrotron radiation micro X-ray fluorescence (HE-SR-μ-XRF) analysis and X-ray absorption fine structure (XAFS) analysis were applied to reveal accumulation mechanism of Cd in a generated callus of Cd hyperaccumulator fern Athyrium yokoscense. The effects of plant age on the distributions and the chemical forms of Cd were examined using the plant grown in the 1/2 M Murashige and Skoog (MS) medium containing 200 μM Cd. The callus grew vigorously with periodical medium change. The μ-XRF imaging of the mature and young root showed that Cd was located around the cell wall of the epidermis, cortex, endodermis and vascular bundles. It is estimated that Cd absorbed from the root was transported to the shoots via the apoplast. On the other hand, Cd was accumulated in the cell wall of the epidermis, cortex and vascular bundles in the stem. Furthermore, the concentration of Cd in the vascular bundles of the mature stem was higher than that of the young stem. On the other hand, Cd located in whole area in the leaf. The Cd K-edge XAFS analysis revealed that the majority of Cd in the roots of both mature and immature stages of A. yokoscense is bounded to the oxygen ligands. In contrast, it is found that Cd was bound to sulfur ligands as well as to oxygen ligands in the shoots. (author)

Role of LAP+CD4+ T cells in the tumor microenvironment of colorectal cancer.

Science.gov (United States)

Zhong, Wu; Jiang, Zhi-Yuan; Zhang, Lei; Huang, Jia-Hao; Wang, Shi-Jun; Liao, Cun; Cai, Bin; Chen, Li-Sheng; Zhang, Sen; Guo, Yun; Cao, Yun-Fei; Gao, Feng

2017-01-21

To investigate the abundance and potential functions of LAP + CD4 + T cells in colorectal cancer (CRC). Proportions of LAP + CD4 + T cells were examined in peripheral blood and tumor/paratumor tissues of CRC patients and healthy controls using flow cytometry. Expression of phenotypic markers such as forkhead box (Fox)p3, cytotoxic T-lymphocyte-associated protein (CTLA)-4, chemokine CC receptor (CCR)4 and CCR5 was measured using flow cytometry. LAP - CD4 + and LAP + CD4 + T cells were isolated using a magnetic cell-sorting system and cell purity was analyzed by flow cytometry. Real-time quantitative polymerase chain reaction was used to measure expression of cytokines interleukin (IL)-10 and transforming growth factor (TGF)-β. The proportion of LAP + CD4 + T cells was significantly higher in peripheral blood from patients (9.44% ± 3.18%) than healthy controls (1.49% ± 1.00%, P CD4 + T cells was significantly higher in tumor tissues (11.76% ± 3.74%) compared with paratumor tissues (3.87% ± 1.64%, P CD4 + T cells and TNM stage ( P cell sorting gave an overall enrichment of LAP + CD4 + T cells (95.02% ± 2.87%), which was similar for LAP - CD4 + T cells (94.75% ± 2.76%). In contrast to LAP - CD4 + T cells, LAP + CD4 + T cells showed lower Foxp3 expression but significantly higher levels of CTLA-4, CCR4 and CCR5 ( P CD4 + T cells expressed significantly larger amounts of IL-10 and TGF-β but lower levels of IL-2, IL-4, IL-17 and interferon-γ, compared with LAP - CD4 + T cells. LAP + CD4 + T cells accumulated in the tumor microenvironment of CRC patients and were involved in immune evasion mediated by IL-10 and TGF-β.

Low Doses of Cadmium Chloride and Methallothionein-1-Bound Cadmium Display Different Accumulation Kinetics and Induce Different Genes in Cells of the Human Nephron

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Dana Cucu

2011-08-01

Full Text Available Background/Aims: The present study was conducted to investigate the renal tubular handling of inorganic cadmium (Cd2+ by exposing primary human tubular cell cultures to physiologically relevant doses of cadmium chloride (CdCl2. Furthermore, the cellular accumulation of Cd2+ was compared to that of metallothionein-1-bound Cd (Cd7MT-1. Finally, this study aimed to investigate the effect of the accumulation of Cd (both Cd2+ and Cd7MT-1 in renal cells on the expression of genes relevant to nephrotoxic processes. Methods: Cd concentration was measured using atomic absorption spectrometry. mRNA expression was evaluated by quantitative real-time RT-PCR. Results: Cd2+ accumulated into human tubular cells in a concentration- and time-dependent way. Furthermore, cellular accumulation of Cd2+ was different from the cellular accumulation of Cd7MT-1, indicative for different uptake routes. Finally, mRNA expression of the genes encoding the anti-oxidative proteins metallothionein-1 (MT-1 and heme-oxygenase-1 (HO-1 as well as the pro-apoptotic Bcl-2-associated X protein (Bax were upregulated by CdCl2 and not by Cd7MT1. Conclusion: In the presence of physiologically relevant Cd concentrations, tubular accumulation of the element in its inorganic form is different from that of Cd7MT-1. Furthermore, the tubular accumulation of inorganic Cd induces mRNA expression of genes of which the protein products may play a role in Cd-associated renal toxicity.

Which Factors Determine Metal Accumulation in Agricultural Soils in the Severely Human-Coupled Ecosystem?

Science.gov (United States)

Xu, Li; Cao, Shanshan; Wang, Jihua; Lu, Anxiang

2016-05-17

Agricultural soil is typically an important component of urban ecosystems, contributing directly or indirectly to the general quality of human life. To understand which factors influence metal accumulation in agricultural soils in urban ecosystems is becoming increasingly important. Land use, soil type and urbanization indicators all account for considerable differences in metal accumulation in agricultural soils, and the interactions between these factors on metal concentrations were also examined. Results showed that Zn, Cu, and Cd concentrations varied significantly among different land use types. Concentrations of all metals, except for Cd, were higher in calcareous cinnamon soil than in fluvo-aquic soil. Expansion distance and road density were adopted as urbanization indicators, and distance from the urban center was significantly negatively correlated with concentrations of Hg, and negatively correlated with concentrations of Zn, and road density was positively correlated with Cd concentrations. Multivariate analysis of variance indicated that Hg concentration was significantly influenced by the four-way interaction among all factors. The results in this study provide basic data to support the management of agricultural soils and to help policy makers to plan ahead in Beijing.

PENGARUH LOGAM BERAT Cd, Pb TERHADAP PERUBAHAN WARNA BATANG DAN DAUN SAYURAN

Directory of Open Access Journals (Sweden)

Hening Widowati

2011-04-01

Full Text Available Cd, Pb heavy metal absorption in aquatic vegetables: Genjer (Limnocharis flava, Kangkung air (Ipomoea aquatica Forsk dan Selada air (Nasturtium officinale R. Br, studied to see the relationship with green figure scale. The research objective was to identify the accumulated Cd, Pb in the consumed organ vegetable, and their impacts to the levels of green figure scale. The research was undertaken by planting three kinds of the aquatic vegetables to the contaminated pure Cd,pure Pb media, mixture of Cd and Pb with factorial randomized block design. Data were analyzed by factorial One-Way Anova and further test of Duncan and HSD to see the difference of Cd, Pb and green figure scale, regression and correlation to know the contribution of Cd, Pb in influencing the green figure scale. Variety of vegetables, media, organ, and the interaction influences the accumulation of Cd, Pb and level of green figure scale. There is a relationship between Cd, Pb metal accumulation to the level of green figure scale of the aquatic vegetables, with negative correlation that Cd, Pb decreased the vegetable green figure scale.

Co-contamination of Cu and Cd in paddy fields: Using periphyton to entrap heavy metals

Energy Technology Data Exchange (ETDEWEB)

Yang, Jiali [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008 (China); College of Resource and Environment, University of Chinese Academy of Sciences, Beijing 100049 (China); Tang, Cilai [Department of Environmental Engineering, College of Hydraulic & Environmental Engineering, China Three Gorges University, Yichang 443002 (China); Wang, Fengwu [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008 (China); School of Civil Engineering, East China Jiaotong University, 808 Shuang Gang East Road, Nanchang, Jiangxi 330013 (China); Wu, Yonghong, E-mail: yhwu@issas.ac.cn [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008 (China)

2016-03-05

Highlights: • Periphyton was capable of simultaneously entrapping Cu and Cd from paddy fields. • Cu and Cd bioavailability decreased with time after exposure to periphyton. • Periodic adsorption–desorption was the main mechanism used to remove Cd and Cu. • Periphyton was able to adapt to steady accumulation of Cu and Cd. • The inclusion of periphyton will help entrap heavy metals in paddy fields. - Abstract: The ubiquitous native periphyton was used to entrap Cu and Cd from paddy fields. Results showed that Cu- and Cd-hydrate species such as CuOH{sup +}, Cu{sub 2}(OH){sub 2}{sup 2+}, CdOH{sup +}, and Cu{sub 3}(OH){sub 4}{sup 2+} decreased with time in the presence of periphyton. When the initial concentrations of Cu and Cd were 10 mg/L, the heavy metal content in the periphyton fluctuated from 145.20 mg/kg to 342.42 mg/kg for Cu and from 101.75 mg/kg to 236.29 mg/kg for Cd after 2 h exposure. The concentration of Cd in periphytic cells varied from 42.93 mg/kg to 174 mg/kg after 2 h. The dominant periphyton microorganism species shifted from photoautotrophs to heterotrophs during the exposure of periphyton to Cu and Cd co-contamination. Although Cu and Cd could inhibit periphyton photosynthesis and carbon utilization, the periphyton was able to adapt to the test conditions. Cu and Cd accumulation in rice markedly decreased in the presence of periphyton while the number of rice seeds germinating was higher in the periphyton treatments. These results suggest that the inclusion of native periphyton in paddy fields provides a promising buffer to minimize the effects of Cu and Cd pollution on rice growth and food safety.

Cd translocation into generative organs of linseed (Linum usitatissimum L.)

Energy Technology Data Exchange (ETDEWEB)

Becher, M.; Woerner, A.; Schubert, S. [Giessen Univ. (Germany). Inst. fuer Pflanzenernaehrung

1997-12-31

Linseed is able to accumulate considerably high concentrations of Cd in generative organs, the dietary critical value of 0.3 {mu}g Cd/g seed often being exceeded. Differences between genotypes of linseed in this respect, however, have been observed but the underlying mechanisms responsible for these differences are unknown. The aim of the present work was to identify these mechanisms by studying the Cd accumulation of the linseed genotypes Antares and McGregor which differ in their ability to accumulate Cd in the seeds. Cultivar Antares is a high and cv. McGregor is low Cd accumulator which was confirmed in a pot experiment. It was found that the differences between these genotypes were Cd-specific and were caused neither by single seed weight nor by Cd translocation into the shoot. The distribution pattern of Cd within mature capsules between the pericarp and the seeds differed from that of Ca which was used as a phloem-immobile reference ion. From these results we conclude that Cd was translocated from the pericarp into the seeds via the phloem. This conclusion was supported by direct Cd determination in collected phloem sap from linseed stems. As sources of seed-Cd we identified the pericarps of capsules and the leaves. The genotype differences concerning the Cd concentrations in the seeds may be explained in terms of differences in phloem translocation of Cd. (orig.) [Deutsch] Oellein vermag Cd in betraechtlichen Konzentrationen in den Samen zu akkumulieren. Aus diesem Grund wird der Grenzwert fuer Diaetlein von 0,3 {mu}g/g Samen im Anbau haeufig ueberschritten. Es gibt jedoch genotypische Unterschiede, deren zugrundeliegende Mechanismen nicht bekannt sind. Das Ziel der vorliegenden Arbeit bestand darin, diese Mechanismen an den Oelleinsorten Antares und McGregor zu untersuchen. Antares akkumuliert grosse, McGregor hingegen geringe Mengen Cd in den Samen. Diese Beobachtungen konnten in einem Gefaessversuch bestaetigt werden. Es wurde gezeigt, dass die

In vivo and in vitro cadmium accumulation during the moult cycle of the male shore crab Carcinus maenas-interaction with calcium metabolism

International Nuclear Information System (INIS)

Norum, Ulrik; Bondgaard, Morten; Pedersen, Thomas V.; Bjerregaard, Poul

2005-01-01

The effect of moult stage on cadmium accumulation and distribution was investigated in vivo in male shore crabs Carcinus maenas exposed to 1 mg Cd l -1 for 7 days. The accumulation of cadmium in all tissues examined was markedly higher in postmoult (A 1-2 and B 1-2 ) compared to intermoult (C 1 , C 3 and C 4 ) and premoult (D 0-3 ). In addition, elevated levels of cadmium were found in gills of late premoult (D 2-3 ) animals. The total amount of cadmium accumulated in the tissues (haemolymph, gills, midgut gland and muscle) increased from 43 μg Cd in early premoult (D 0-1 ) to 391 μg Cd in late postmoult (B 1-2 ). Gills and midgut gland were the primary cadmium accumulating tissues in C 4 -intermoult and premoult (D 0-3 ); in early postmoult (A 1-2 ) haemolymph and midgut gland were the main cadmium containing tissues, while midgut gland dominated in late postmoult (B 1-2 ) and early intermoult (C 1 and C 3 ). A detailed account of calcium distribution in haemolymph, gills, midgut gland, muscle and exoskeleton during the moult cycle is presented. Mechanistic links between cadmium and calcium uptake in posterior gills of C 4 -intermoult and early postmoult (A 1-2 ) crabs were explored using an in vitro gill perfusion technique. Calcium and cadmium influxes were markedly higher in postmoult compared to intermoult. No differences between intermoult and postmoult effluxes were found for either calcium or cadmium. From intermoult to postmoult net influx increased from 2.4 to 29 μmol Ca 2+ g -1 ww gill h -1 and from 0.24 to 25 nmol Cd 2+ g -1 ww gill h -1 . The results indicate that the postmoult increase in cadmium influx is due to increased active transport of cadmium, at least partly, by accidental uptake via calcium transporting proteins. The in vitro net influx rates corresponded accurately to the observed in vivo accumulation of both cadmium and calcium. Although cadmium accumulation and distribution are clearly linked to changes in calcium requirements, cadmium

Human leucocyte antigen class I-redirected anti-tumour CD4+ T cells require a higher T cell receptor binding affinity for optimal activity than CD8+ T cells.

Science.gov (United States)

Tan, M P; Dolton, G M; Gerry, A B; Brewer, J E; Bennett, A D; Pumphrey, N J; Jakobsen, B K; Sewell, A K

2017-01-01

CD4 + T helper cells are a valuable component of the immune response towards cancer. Unfortunately, natural tumour-specific CD4 + T cells occur in low frequency, express relatively low-affinity T cell receptors (TCRs) and show poor reactivity towards cognate antigen. In addition, the lack of human leucocyte antigen (HLA) class II expression on most cancers dictates that these cells are often unable to respond to tumour cells directly. These deficiencies can be overcome by transducing primary CD4 + T cells with tumour-specific HLA class I-restricted TCRs prior to adoptive transfer. The lack of help from the co-receptor CD8 glycoprotein in CD4 + cells might result in these cells requiring a different optimal TCR binding affinity. Here we compared primary CD4 + and CD8 + T cells expressing wild-type and a range of affinity-enhanced TCRs specific for the HLA A*0201-restricted NY-ESO-1- and gp100 tumour antigens. Our major findings are: (i) redirected primary CD4 + T cells expressing TCRs of sufficiently high affinity exhibit a wide range of effector functions, including cytotoxicity, in response to cognate peptide; and (ii) optimal TCR binding affinity is higher in CD4 + T cells than CD8 + T cells. These results indicate that the CD4 + T cell component of current adoptive therapies using TCRs optimized for CD8 + T cells is below par and that there is room for substantial improvement. © 2016 The Authors. Clinical & Experimental Immunology published by John Wiley & Sons Ltd on behalf of British Society for Immunology.

The landsnail Cepaea nemoralis regulates internal Cd levels when fed on Cd-enriched stinging nettle (Urtica dioica) leaves at low, field-relevant concentrations.

NARCIS (Netherlands)

Notten, M.J.M.; Oosthoek, A.; Rozema, J.; Aerts, R.

2006-01-01

We studied Cd accumulation in Cepaea nemoralis snails at low, but field-relevant Cd concentrations in the diet (Urtica dioica leaves). Six treatments of U. dioica plants were grown, resulting in leaf Cd concentrations between 0 and 2.6 μg g

Effect of different N fertilizer forms on antioxidant capacity and grain yield of rice growing under Cd stress

International Nuclear Information System (INIS)

Jalloh, Mohamed Alpha; Chen Jinghong; Zhen Fanrong; Zhang Guoping

2009-01-01

Cadmium contamination in soil has become a serious issue in sustainable agriculture production and food safety. A pot experiment was conducted to study the influence of four N fertilizer forms on grain yield, Cd concentration in plant tissues and oxidative stress under two Cd levels (0 and 100 mg Cd kg -1 soil). The results showed that both N form and Cd stress affected grain yield, with urea-N and NH 4 + -N treatments having significantly higher grain yields, and Cd addition reducing yield. NO 3 - -N and NH 4 + -N treated plants had the highest and lowest Cd concentration in plant tissues, respectively. Urea-N and NH 4 + -N treatments had significantly higher N accumulation in plant tissues than other two N treatments. Cd addition caused a significant increase in leaf superoxide dismutase (SOD) and peroxidase (POD) activities for all N treatments, except for NO 3 - -N treatment, with urea-N and NH 4 + -N treated plants having more increase than organic-N treated ones. The results indicated that growth inhibition, yield reduction and Cd uptake of rice plants in response to Cd addition varied with the N fertilizer form

Effect of different N fertilizer forms on antioxidant capacity and grain yield of rice growing under Cd stress.

Science.gov (United States)

Jalloh, Mohamed Alpha; Chen, Jinghong; Zhen, Fanrong; Zhang, Guoping

2009-03-15

Cadmium contamination in soil has become a serious issue in sustainable agriculture production and food safety. A pot experiment was conducted to study the influence of four N fertilizer forms on grain yield, Cd concentration in plant tissues and oxidative stress under two Cd levels (0 and 100 mg Cd kg(-1)soil). The results showed that both N form and Cd stress affected grain yield, with urea-N and NH(4)(+)-N treatments having significantly higher grain yields, and Cd addition reducing yield. NO(3)(-)-N and NH(4)(+)-N treated plants had the highest and lowest Cd concentration in plant tissues, respectively. Urea-N and NH(4)(+)-N treatments had significantly higher N accumulation in plant tissues than other two N treatments. Cd addition caused a significant increase in leaf superoxide dismutase (SOD) and peroxidase (POD) activities for all N treatments, except for NO(3)(-)-N treatment, with urea-N and NH(4)(+)-N treated plants having more increase than organic-N treated ones. The results indicated that growth inhibition, yield reduction and Cd uptake of rice plants in response to Cd addition varied with the N fertilizer form.

Divalent metal (Ca, Cd, Mn, Zn) uptake and interactions in the aquatic insect Hydropsyche sparna.

Science.gov (United States)

Poteat, Monica D; Díaz-Jaramillo, Mauricio; Buchwalter, David B

2012-05-01

Despite their ecological importance and prevalent use as ecological indicators, the trace element physiology of aquatic insects remains poorly studied. Understanding divalent metal transport processes at the water-insect interface is important because these metals may be essential (e.g. Ca), essential and potentially toxic (e.g. Zn) or non-essential and toxic (e.g. Cd). We measured accumulation kinetics of Zn and Cd across dissolved concentrations ranging 4 orders of magnitude and examined interactions with Ca and Mn in the caddisfly Hydropsyche sparna. Here, we provide evidence for at least two transport systems for both Zn and Cd, the first of which operates at concentrations below 0.8 μmol l(-1) (and is fully saturable for Zn). We observed no signs of saturation of a second lower affinity transport system at concentrations up to 8.9 μmol l(-1) Cd and 15.3 μmol l(-1) Zn. In competition studies at 0.6 μmol l(-1) Zn and Cd, the presence of Cd slowed Zn accumulation by 35% while Cd was unaffected by Zn. At extreme concentrations (listed above), Cd accumulation was unaffected by the presence of Zn whereas Zn accumulation rates were reduced by 58%. Increasing Ca from 31.1 μmol l(-1) to 1.35 mmol l(-1) resulted in only modest decreases in Cd and Zn uptake. Mn decreased adsorption of Cd and Zn to the integument but not internalization. The L-type Ca(2+) channel blockers verapamil and nifedipine and the plasma membrane Ca(2+)-ATPase inhibitor carboxyeosin had no influence on Ca, Cd or Zn accumulation rates, while Ruthenium Red, a Ca(2+)-ATPase inhibitor, significantly decreased the accumulation of all three in a concentration-dependent manner.

Higher accumulation of F1-V fusion recombinant protein in plants after induction of protein body formation.

Science.gov (United States)

Alvarez, M Lucrecia; Topal, Emel; Martin, Federico; Cardineau, Guy A

2010-01-01

Improving foreign protein accumulation is crucial for enhancing the commercial success of plant-based production systems since product yields have a major influence on process economics. Cereal grain evolved to store large amounts of proteins in tightly organized aggregates. In maize, gamma-Zein is the major storage protein synthesized by the rough endoplasmic reticulum (ER) and stored in specialized organelles called protein bodies (PB). Zera (gamma-Zein ER-accumulating domain) is the N-terminal proline-rich domain of gamma-zein that is sufficient to induce the assembly of PB formation. Fusion of the Zera domain to proteins of interest results in assembly of dense PB-like, ER-derived organelles, containing high concentration of recombinant protein. Our main goal was to increase recombinant protein accumulation in plants in order to enhance the efficiency of orally-delivered plant-made vaccines. It is well known that oral vaccination requires substantially higher doses than parental formulations. As a part of a project to develop a plant-made plague vaccine, we expressed our model antigen, the Yersinia pestis F1-V antigen fusion protein, with and without a fused Zera domain. We demonstrated that Zera-F1-V protein accumulation was at least 3x higher than F1-V alone when expressed in three different host plant systems: Ncotiana benthamiana, Medicago sativa (alfalfa) and Nicotiana tabacum NT1 cells. We confirmed the feasibility of using Zera technology to induce protein body formation in non-seed tissues. Zera expression and accumulation did not affect plant development and growth. These results confirmed the potential exploitation of Zera technology to substantially increase the accumulation of value-added proteins in plants.

Transporters for Antiretroviral Drugs in Colorectal CD4+ T Cells and Circulating α4β7 Integrin CD4+ T Cells: Implications for HIV Microbicides.

Science.gov (United States)

Mukhopadhya, Indrani; Murray, Graeme I; Duncan, Linda; Yuecel, Raif; Shattock, Robin; Kelly, Charles; Iannelli, Francesco; Pozzi, Gianni; El-Omar, Emad M; Hold, Georgina L; Hijazi, Karolin

2016-09-06

CD4+ T lymphocytes in the colorectal mucosa are key in HIV-1 transmission and dissemination. As such they are also the primary target for antiretroviral (ARV)-based rectal microbicides for pre-exposure prophylaxis. Drug transporters expressed in mucosal CD4+ T cells determine ARV distribution across the cell membrane and, most likely, efficacy of microbicides. We describe transporters for antiretroviral drugs in colorectal mucosal CD4+ T lymphocytes and compare gene expression with circulating α4β7+CD4+ T cells, which traffic to the intestine and have been shown to be preferentially infected by HIV-1. Purified total CD4+ T cells were obtained from colorectal tissue and blood samples by magnetic separation. CD4+ T cells expressing α4β7 integrin were isolated by fluorescence-activated cell sorting from peripheral blood mononuclear cells of healthy volunteers. Expressions of 15 efflux and uptake drug transporter genes were quantified using Taqman qPCR assays. Expression of efflux transporters MRP3, MRP5, and BCRP and uptake transporter CNT2 were significantly higher in colorectal CD4+ T cells compared to circulating CD4+ T cells (p = 0.01-0.03). Conversely, circulating α4β7+CD4+ T cells demonstrated significantly higher expression of OATPD compared to colorectal CD4+ T cells (p = 0.001). To the best of our knowledge this is the first report of drug transporter gene expression in colorectal CD4+ and peripheral α4β7+CD4+ T cells. The qualitative and quantitative differences in drug transporter gene expression profiles between α4β7+CD4+ T cells and total mucosal CD4+ T cells may have significant implications for the efficacy of rectally delivered ARV-microbicides. Most notably, we have identified efflux drug transporters that could be targeted by selective inhibitors or beneficial drug-drug interactions to enhance intracellular accumulation of antiretroviral drugs.

Choroid plexus accumulates cadmium, lead, mercury and arsenic

International Nuclear Information System (INIS)

Zheng, W.; Perry, D.F.; Nelson, D.L.; Aposhian, H.V.

1990-01-01

The choroid plexus (CP) is the site of the formation of cerebrospinal fluid (CSF) and the major location of the blood-CSF barrier. The property of CP in sequestering heavy metals so as to prevent their entering CSF was studied in male rats and rabbits. The content of Cd, Pb and Hg in rat tissues was determined by AAS and radioactive isotopes 24 hours after a single exposure. Cd was 33 fold greater in CP than in brain cortex (BC) after 4 mg Cd/kg ip. No Cd was detected in CSF. In rats given 27 mg Pb/kg ip, Pb in CP was 57 fold greater than in BC and 12 fold greater in blood than CSF. Rats exposed to 1 mg Hg/kg ip showed a 13 fold greater Hg content in CP than in BC. Hg was 78 fold lower in CSF than in blood. Arsenic distribution in rabbits was determined 4 hours after iv injection of 1.7 mg As 5+ /kg. As in CP was 6 fold greater than in BC and in blood it was 26 fold more than in CSF. Total thiol content in BC was significantly higher than that in CP. In CP, 87% of total thiol was non-protein bound thiol. Results suggest that the CP accumulates toxic metals such as Cd, Pb, Hg and As and acts as a filter to limit these metals passing through the blood-CSF barrier. CdCl 2 , Pb acetate, HgCl 2 or Na arsenate was used for injection

A cloned prokaryotic Cd2+ P-type ATPase increases yeast sensitivity to Cd2+

International Nuclear Information System (INIS)

Wu, C.-C.; Bal, Nathalie; Perard, Julien; Lowe, Jennifer; Boscheron, Cecile; Mintz, Elisabeth; Catty, Patrice

2004-01-01

CadA, the P1-type ATPase involved in Listeria monocytogenes resistance to Cd 2+ , was expressed in Saccharomyces cerevisiae and did just the opposite to what was expected, as it strikingly decreased the Cd 2+ tolerance of these cells. Yeast cells expressing the non-functional mutant Asp 398 Ala could grow on selective medium containing up to 100 μM Cd 2+ , whereas those expressing the functional protein could not grow in the presence of 1 μM Cd 2+ . The CadA-GFP fusion protein was localized in the endoplasmic reticulum membrane, suggesting that yeast hyper-sensitivity was due to Cd 2+ accumulation in the reticulum lumen. CadA is also known to transport Zn 2+ , but Zn 2+ did not protect the cells against Cd 2+ poisoning. In the presence of 10 μM Cd 2+ , transformed yeasts survived by rapid loss of their expression vector

Dopamine Increases CD14+CD16+ Monocyte Migration and Adhesion in the Context of Substance Abuse and HIV Neuropathogenesis

Science.gov (United States)

Coley, Jacqueline S.; Calderon, Tina M.; Gaskill, Peter J.; Eugenin, Eliseo A.; Berman, Joan W.

2015-01-01

Drug abuse is a major comorbidity of HIV infection and cognitive disorders are often more severe in the drug abusing HIV infected population. CD14+CD16+ monocytes, a mature subpopulation of peripheral blood monocytes, are key mediators of HIV neuropathogenesis. Infected CD14+CD16+ monocyte transmigration across the blood brain barrier mediates HIV entry into the brain and establishes a viral reservoir within the CNS. Despite successful antiretroviral therapy, continued influx of CD14+CD16+ monocytes, both infected and uninfected, contributes to chronic neuroinflammation and the development of HIV associated neurocognitive disorders (HAND). Drug abuse increases extracellular dopamine in the CNS. Once in the brain, CD14+CD16+ monocytes can be exposed to extracellular dopamine due to drug abuse. The direct effects of dopamine on CD14+CD16+ monocytes and their contribution to HIV neuropathogenesis are not known. In this study, we showed that CD14+CD16+ monocytes express mRNA for all five dopamine receptors by qRT-PCR and D1R, D5R and D4R surface protein by flow cytometry. Dopamine and the D1-like dopamine receptor agonist, SKF38393, increased CD14+CD16+ monocyte migration that was characterized as chemokinesis. To determine whether dopamine affected cell motility and adhesion, live cell imaging was used to monitor the accumulation of CD14+CD16+ monocytes on the surface of a tissue culture dish. Dopamine increased the number and the rate at which CD14+CD16+ monocytes in suspension settled to the dish surface. In a spreading assay, dopamine increased the area of CD14+CD16+ monocytes during the early stages of cell adhesion. In addition, adhesion assays showed that the overall total number of adherent CD14+CD16+ monocytes increased in the presence of dopamine. These data suggest that elevated extracellular dopamine in the CNS of HIV infected drug abusers contributes to HIV neuropathogenesis by increasing the accumulation of CD14+CD16+ monocytes in dopamine rich brain

Zinc supplementation protects against cadmium accumulation and cytotoxicity in Madin-Darby bovine kidney cells.

Directory of Open Access Journals (Sweden)

Ding Zhang

Full Text Available Cadmium ions (Cd2+ have been reported to accumulate in bovine tissues, although Cd2+ cytotoxicity has not been investigated thoroughly in this species. Zinc ions (Zn2+ have been shown to antagonize the toxic effects of heavy metals such as Cd2+ in some systems. The present study investigated Cd2+ cytotoxicity in Madin-Darby bovine kidney (MDBK epithelial cells, and explored whether this was modified by Zn2+. Exposure to Cd2+ led to a dose- and time-dependent increase in apoptotic cell death, with increased intracellular levels of reactive oxygen species and mitochondrial damage. Zn2+ supplementation alleviated Cd2+-induced cytotoxicity and this protective effect was more obvious when cells were exposed to a lower concentration of Cd2+ (10 μM, as compared to 50 μM Cd2+. This indicated that high levels of Cd2+ accumulation might induce irreversible damage in bovine kidney cells. Metallothioneins (MTs are metal-binding proteins that play an essential role in heavy metal ion detoxification. We found that co-exposure to Zn2+ and Cd2+ synergistically enhanced RNA and protein expression of MT-1, MT-2, and the metal-regulatory transcription factor 1 in MDBK cells. Notably, addition of Zn2+ reduced the amounts of cytosolic Cd2+ detected following MDBK exposure to 10 μM Cd2+. These findings revealed a protective role of Zn2+ in counteracting Cd2+ uptake and toxicity in MDBK cells, indicating that this approach may provide a means to protect livestock from excessive Cd2+ accumulation.

Mammalian hair as an accumulative bioindicator of metal bioavailability in Australian terrestrial environments

International Nuclear Information System (INIS)

McLean, Christopher M.; Koller, Claudia E.; Rodger, John C.; MacFarlane, Geoff R.

2009-01-01

The current study represents the first investigation of the suitability of marsupial and eutherian mammalian hair as indicator tissue for metal exposure and accumulation within contaminated Australian terrestrial ecosystems. A soil metal contamination gradient was established across 22 sites at increasing distances from a decommissioned Lead/Zinc smelter in NSW, Australia. Within each site, soil and small mammal populations were sampled. An Australian native marsupial, the insectivorous Brown Antechinus, Antechinus stuartii: Dasyuridae, and introduced rodents, the omnivorous Brown or Norway Rat, Rattus norvegicus: Muridae and the Black Rat, Rattus rattus: Muridae were assessed for hair concentrations of Cadmium (Cd), Copper (Cu), Lead (Pb) and Zinc (Zn). Metals in soil were most elevated at sites within close proximity to the smelter, with soil metal concentrations decreasing with distance from the smelter. The non-essential metals Pb and Cd were accumulated in hair, both metals exhibiting positive linear relationships with environmental exposure (soil metal concentrations). When the variables of weight and snout-vent length were considered, no further contribution in terms of explaining the variability in hair Cd or Pb was observed for all species examined. The essential metals Cu and Zn were regulated in hair, remaining similar across the metal contamination gradient. A significant negative correlation between snout-vent length and hair Cu concentration was found for the Brown Rat; greater hair Cu concentrations were found in smaller individuals of this species. Accumulation of Pb to hair was similar among species while concentrations of Cd in Brown Rat hair were higher than both Black Rat and Brown Antechinus hair. As each of the three aforementioned species exhibit similar bioaccumulation relationships for Pb, we suggest that sampling hair from introduced rodents (pest species) may provide a suitable proxy for the assessment of Pb bioavailability for a range of

Mammalian hair as an accumulative bioindicator of metal bioavailability in Australian terrestrial environments

Energy Technology Data Exchange (ETDEWEB)

McLean, Christopher M. [Ecology and Ecotoxicology Laboratory, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW Australia (Australia); Centre for the Risk Management of Bushfires, Institute for Conservation Biology and Law, University of Wollongong, Wollongong, NSW (Australia); Koller, Claudia E. [Ecology and Ecotoxicology Laboratory, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW Australia (Australia); Rodger, John C. [Marsupial Research Laboratory, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW Australia (Australia); MacFarlane, Geoff R., E-mail: geoff.macfarlane@newcastle.edu.au [Ecology and Ecotoxicology Laboratory, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW Australia (Australia)

2009-05-15

The current study represents the first investigation of the suitability of marsupial and eutherian mammalian hair as indicator tissue for metal exposure and accumulation within contaminated Australian terrestrial ecosystems. A soil metal contamination gradient was established across 22 sites at increasing distances from a decommissioned Lead/Zinc smelter in NSW, Australia. Within each site, soil and small mammal populations were sampled. An Australian native marsupial, the insectivorous Brown Antechinus, Antechinus stuartii: Dasyuridae, and introduced rodents, the omnivorous Brown or Norway Rat, Rattus norvegicus: Muridae and the Black Rat, Rattus rattus: Muridae were assessed for hair concentrations of Cadmium (Cd), Copper (Cu), Lead (Pb) and Zinc (Zn). Metals in soil were most elevated at sites within close proximity to the smelter, with soil metal concentrations decreasing with distance from the smelter. The non-essential metals Pb and Cd were accumulated in hair, both metals exhibiting positive linear relationships with environmental exposure (soil metal concentrations). When the variables of weight and snout-vent length were considered, no further contribution in terms of explaining the variability in hair Cd or Pb was observed for all species examined. The essential metals Cu and Zn were regulated in hair, remaining similar across the metal contamination gradient. A significant negative correlation between snout-vent length and hair Cu concentration was found for the Brown Rat; greater hair Cu concentrations were found in smaller individuals of this species. Accumulation of Pb to hair was similar among species while concentrations of Cd in Brown Rat hair were higher than both Black Rat and Brown Antechinus hair. As each of the three aforementioned species exhibit similar bioaccumulation relationships for Pb, we suggest that sampling hair from introduced rodents (pest species) may provide a suitable proxy for the assessment of Pb bioavailability for a range of

Phytoextraction of initial cutting of Salix matsudana for Cd and Cu.

Science.gov (United States)

Wang, Wen-Wen; Cheng, Liu Ke; Hao, Jie Wei; Guan, Xin; Tian, Xing-Jun

2016-06-27

Salix species are widely used as vegetation filters because of their flourishing root system and fast growth rate. However, studies have yet to determine whether the root system functions in vegetable filters with mixed heavy metal (HM) pollution or whether initial cutting participates in the phytoextraction of HMs. This study aims to determine the function of the root system and initial cutting as vegetation filters in the absorption and accumulation of Cd and Cu. Thick (>1 cm in diameter) and fine (phytoextraction capacity of plants. The initial cuttings could also absorb and accumulate HMs in the early growth stages of willow without roots. Cu inhibited the plant absorption and accumulation of Cd and promoted Cd transport to shoots. Cd inhibited the Cu absorption of the root system. Our study provided essential data regarding woody species as vegetation filters of HM pollution.

Expression of an Arabidopsis Ca2+/H+ antiporter CAX1 variant in petunia enhances cadmium tolerance and accumulation.

Science.gov (United States)

Wu, Qingyu; Shigaki, Toshiro; Williams, Kimberly A; Han, Jeung-Sul; Kim, Chang Kil; Hirschi, Kendal D; Park, Sunghun

2011-01-15

Phytoremediation is a cost-effective and minimally invasive technology to cleanse soils contaminated with heavy metals. However, few plant species are suitable for phytoremediation of metals such as cadmium (Cd). Genetic engineering offers a powerful tool to generate plants that can hyperaccumulate Cd. An Arabidopsis CAX1 mutant (CAXcd), which confers enhanced Cd transport in yeast, was ectopically expressed in petunia to evaluate whether the CAXcd expression would enhance Cd tolerance and accumulation in planta. The CAXcd-expressing petunia plants showed significantly greater Cd tolerance and accumulation than the controls. After being treated with either 50 or 100μM CdCl(2) for 6 weeks, the CAXcd-expressing plants showed more vigorous growth compared with controls, and the transgenic plants accumulated significantly more Cd (up to 2.5-fold) than controls. Moreover, the accumulation of Cd did not affect the development and morphology of the CAXcd-expressing petunia plants until the flowering and ultimately the maturing of seeds. Therefore, petunia has the potential to serve as a model species for developing herbaceous, ornamental plants for phytoremediation. Copyright © 2010 Elsevier GmbH. All rights reserved.

The Role of Node Restriction on Cadmium Accumulation in the Brown Rice of 12 Chinese Rice (Oryza sativa L.) Cultivars.

Science.gov (United States)

Huang, Gaoxiang; Ding, Changfeng; Guo, Fuyu; Li, Xiaogang; Zhou, Zhigao; Zhang, Taolin; Wang, Xingxiang

2017-11-29

For selection or breeding of rice (Oryza sativa L.) cultivars with low Cd affinity, the role of node Cd restriction on Cd accumulation in brown rice was studied. A pot experiment was conducted to investigate the concentration of Cd in different sections of 12 Chinese rice cultivars. The results indicated that the Cd accumulation in the brown rice was mainly dependent on the root or shoot Cd concentration. Among the cultivars with nearly equal shoot Cd concentrations, Cd accumulation in brown rice was mainly dependent on the transport of Cd in the shoot. However, the Cd transport in the shoot was significantly restricted by the nodes, especially by the first node. Furthermore, the area of the diffuse vascular bundle in the junctional region of the flag leaf and the first node was a key contributor to the variations in Cd restriction by the nodes.

Health risk assessment of heavy metals in fish and accumulation patterns in food web in the upper Yangtze River, China.

Science.gov (United States)

Yi, Yujun; Tang, Caihong; Yi, Tieci; Yang, Zhifeng; Zhang, Shanghong

2017-11-01

This study aims to concern the distribution of As, Cr, Cd, Hg, Cu, Zn, Pb and Fe in surface sediment, zoobenthos and fishes, and quantify the accumulative ecological risk and human health risk of metals in river ecological system based on the field investigation in the upper Yangtze River. The results revealed high ecological risk of As, Cd, Cu, Hg, Zn and Pb in sediment. As and Cd in fish presented potential human health risk of metals by assessing integrated target hazard quotient results based on average and maximum concentrations, respectively. No detrimental health effects of heavy metals on humans were found by daily fish consumption. While, the total target hazard quotient (1.659) exceeding 1, it meant that the exposed population might experience noncarcinogenic health risks from the accumulative effect of metals. Ecological network analysis model was established to identify the transfer routes and quantify accumulative effects of metals on river ecosystem. Control analysis between compartments showed large predator fish firstly depended on the omnivorous fish. Accumulative ecological risk of metals indicated that zoobenthos had the largest metal propagation risk and compartments located at higher trophic levels were not easier affected by the external environment pollution. A potential accumulative ecological risk of heavy metal in the food web was quantified, and the noncarcinogenic health risk of fish consumption was revealed for the upper reach of the Yangtze River. Copyright © 2017 Elsevier Inc. All rights reserved.

Accumulation of 111In-neutrophils in rabbit skin in allergic and non-allergic inflammatory reactions in vivo. Inhibition by neutrophil pretreatment in vitro with a monoclonal antibody recognizing the CD18 antigen

International Nuclear Information System (INIS)

Nourshargh, S.; Rampart, M.; Hellewell, P.G.; Jose, P.J.; Harlan, J.M.; Edwards, A.J.; Williams, T.J.

1989-01-01

The mAb 60.3 recognizes the neutrophil CD18 Ag. We have investigated the effect of in vitro pretreatment of radiolabeled neutrophils with mAb 60.3 on their accumulation in vivo. Further, we have compared the in vivo effects of mAb 60.3 with its effects on neutrophil adherence in vitro. Neutrophil accumulation in vivo was measured in response to: (1) exogenous mediators FMLP, C5a des Arg, LTB4 and IL-1; (2) endogenous mediators generated in a non-allergic inflammatory reaction induced by zymosan; and (3) endogenous mediators generated in two allergic inflammatory reactions, a passive cutaneous anaphylactic reaction and a reversed passive Arthus reaction in rabbit skin. Pretreatment of neutrophils with mAb 60.3 inhibited their accumulation in all the responses. The results demonstrate that there is a common mechanism mediating neutrophil accumulation in these inflammatory reactions. Neutrophils pretreated with mAb 60.3 were also unresponsive to chemoattractants in in vitro adherence assays. However, the antibody-treated neutrophils responded normally to FMLP and C5a with respect to granular enzyme release. These results suggest that the basal expression of CD18 Ag is important for the adherence of neutrophils to microvascular endothelial cells stimulated by the local generation, or administration, of chemical mediators in vivo. Despite the fact that mediators such as FMLP can increase CD18 expression in vitro, it appears more likely that such mediators act in vivo by inducing a conformational change in the basally expressed neutrophil adhesive molecules

Gibberellic acid alleviates cadmium toxicity by reducing nitric oxide accumulation and expression of IRT1 in Arabidopsis thaliana

International Nuclear Information System (INIS)

Zhu, Xiao Fang; Jiang, Tao; Wang, Zhi Wei; Lei, Gui Jie; Shi, Yuan Zhi; Li, Gui Xin; Zheng, Shao Jian

2012-01-01

Highlights: ► Cd reduces endogenous GA levels in Arabidopsis. ► GA exogenous applied decreases Cd accumulation in plant. ► GA suppresses the Cd-induced accumulation of NO. ► Decreased NO level downregulates the expression of IRT1. ► Suppressed IRT1 expression reduces Cd transport across plasma membrane. - Abstract: Gibberellic acid (GA) is involved in not only plant growth and development but also plant responses to abiotic stresses. Here it was found that treating the plants with GA concentrations from 0.1 to 5 μM for 24 h had no obvious effect on root elongation in the absence of cadmium (Cd), whereas in the presence of Cd 2+ , GA at 5 μM improved root growth, reduced Cd content and lipid peroxidation in the roots, indicating that GA can partially alleviate Cd toxicity. Cd 2+ increased nitric oxide (NO) accumulation in the roots, but GA remarkably reduced it, and suppressed the up-regulation of the expression of IRT1. In contrary, the beneficial effect of GA on alleviating Cd toxicity was not observed in an IRT1 knock-out mutant irt1, suggesting the involvement of IRT1 in Cd 2+ absorption. Furthermore, the GA-induced reduction of NO and Cd content can also be partially reversed by the application of a NO donor (S-nitrosoglutathione [GSNO]). Taken all these together, the results showed that GA-alleviated Cd toxicity is mediated through the reduction of the Cd-dependent NO accumulation and expression of Cd 2+ uptake related gene-IRT1 in Arabidopsis.

The effects of dietary phosphorus and vitamin D3 on the cadmium accumulation in the tissues

International Nuclear Information System (INIS)

Tsuruki, Fukiko; Wung, Houi-Ling; Moriuchi, Sachiko; Hosoya, Norimasa

1979-01-01

The effects of dietary Ca and vitamin D 3 on the Cd accumulation in the liver and the kidney were observed and discussed in relation with the responses to the intestinal Ca transport and vitamin D dependent calcium binding protein (CaBP). 1. Ca transport in rat duodenum was significantly increased by vitamin D 3 , especially in rats raised on low P diet. However, this effect was reduced in Cd-exposed rats. 2. 45 Ca binding activity of the smaller CaBP (PIII), which was found predominantly in the duodenum and jejunum was increased by low P diet. However, in Cd-exposed rats, 45 Ca binding activity was suppressed significantly. On the other hand, the larger CaBP (PII) found mainly in jejunum and ileum showed a good response to vitamin D 3 , too, but not influenced by dietary P and Cd levels as the smaller CaBP. 3. Renal Cd accumulation was influenced by neither dietary P nor vitamin D 3 . However, hepatic Cd accumulation was significantly decreased in vitamin D 3 repleted rat, although it was not influenced by dietary P. These results suggest that dietary P modulates the inhibitory effect of Cd on intestinal vitamin D-stimulated Ca transport, presumably through the inhibition of Ca binding to the smaller CaBP (PIII). But Cd accumulation in the liver was decreased in vitamin D repleted groups, presumably, vitamin D dependent CaBP acts as the barrier in the Cd-exposed rats. (author)

Metal accumulation in Nitellopsis obtusa cells from the laboratory solution

International Nuclear Information System (INIS)

Marciulioniene, D.; Montvydiene, D.; Ceburnis, D.

2001-01-01

The ability of Nitellopsis obtusa to accumulate heavy metals from the laboratory solution containing ions of Cd2+, Cr6+, Cu2+, Mn2+, Ni2+, Pb2+ and Zn2+ was investigated. Concentrations of heavy metals in the algae cells were determined, and the accumulation coefficient (AC) of heavy metals in the live cells (in the wall and the protoplast), in the dead cells (in the wall), and in the cells which have lost turgor were estimated. It was found that, according to the accumulation coefficient values in the cell wall of N. obtusa, the studied metals followed the order: Cr6+ < Pb2+ < Ni2+ < Cd2+ < Cu2+ < Zn2+ < Mn2+, while according to the accumulation coefficient values in the protoplast, the order was: Pb2+ < Cr6+ < Ni2+ < Zn2+ < Cd2+ < Cu2+ < Mn2+ . It was demonstrated that in both media metals were accumulated very similarly. The difference between AC in the cell walls of the live and dead cells was negligible. The obtained data allowed to conclude that all investigated metals were not only absorbed in the algae cell wall but they were intensively up taken into the cell. Data showed that among all investigated metals Cr6+ was the least absorbed in the cell wall, while Pb was predominantly absorbed in the cell wall, as well as Cd2+ and Cu2+ were more intensively up taken into the cell than other metals It was established that Mn2+ was Intensively adsorbed in the cell wall, and its uptake into the cell was intensive, too. (author)

Cadmium accumulation and its effect on the in vitro growth of woody fleabane and mycorrhized white birch

Energy Technology Data Exchange (ETDEWEB)

Fernandez, R.; Bertrand, A.; Casares, A. [Departamento de Biologia de Organismos y Sistemas, Oviedo University, Catedratico Rodrigo Uria s/n, 33071 Oviedo (Spain); Garcia, R. [Departamento de Quimica Fisica y Analitica, Oviedo University, Julian Claveria s/n, 33071 Oviedo (Spain); Gonzalez, A. [Departamento de Biologia de Organismos y Sistemas, Oviedo University, Catedratico Rodrigo Uria s/n, 33071 Oviedo (Spain)], E-mail: aidag@uniovi.es; Tames, R.S. [Departamento de Biologia de Organismos y Sistemas, Oviedo University, Catedratico Rodrigo Uria s/n, 33071 Oviedo (Spain)

2008-04-15

The effect of Cd on woody fleabane (Dittrichia viscosa (L.) Greuter) and white birch (Betula celtiberica Rothm. and Vasc.) was examined. Woody fleabane and white birch were grown in vitro in Murashige, T., Skoog, F., [1962. A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant. 15, 473-479] (MS) plus Cd (10 mg Cd kg{sup -1}) and except for root length in white birch, plant development was inhibited when Cd was added. Cd accumulation in above-ground tissues showed differences among clones, reaching 1300 and 463 mg Cd kg{sup -1} dry wt. in selected clones of woody fleabane and white birch, respectively. Tolerance of Paxillus filamentosus (Scop) Fr. to Cd was also examined before mycorrhization. Plants of mycorrhized white birch grown in the presence of Cd had a better development and accumulated more Cd in their shoots than the non-mycorrhized ones. The use of selected clones of woody fleabane and the mycorrhization of white birch enhance extraction efficiency from contaminated soils in phytoremediation programs. - The high accumulation of Cd observed in selected clones of Dittrichia viscosa and mycorrhized Betula celtiberica grown in vitro implies a potential application for phytoextraction.

Transport of Cd and Zn to seeds of Indian mustard (Brassica juncea) during specific stages of plant growth and development.

Science.gov (United States)

Sankaran, Renuka P; Ebbs, Stephen D

2008-01-01

The accumulation of excess Cd in the seeds of cereal and other crops compromises their commercial value and presents a potential risk to human health. Indian mustard [Brassica juncea (L.) Czern.] is a moderate accumulator of heavy metals such as Cd and Zn, and the seeds are consumed throughout the world, particularly in the Indian subcontinent. The study here examined the transport of Cd into Indian mustard plants and to seeds as a function of external Cd and the stage of the life cycle (vegetative growth, flowering and seed set) to identify critical developmental windows where transport from roots to seeds was the greatest. Plants were also treated simultaneously with Zn to determine if Zn fertilization mitigated the transport of Cd to seeds. Plants treated with Cd during the seed set accumulated the highest concentrations of Cd, exceeding 8 mg kg(-1) dry weight in some instances. Cadmium accumulated during vegetative growth was not highly redistributed to seeds. No effects of Zn were observed with regard to Cd redistribution to seeds. This may be because of the relatively small Zn : Cd ratios tested. However, the results suggest that if Zn fertilization is to be used to reduce the Cd accumulation in seeds of this species, that plants should be treated during the seed set stage. As the seeds of Indian mustard consistently accumulated Cd to concentrations that exceed acceptable limits for food crops, additional study of Cd redistribution in this species is warranted.

CD28-Negative CD4+ and CD8+ T Cells in Antiretroviral Therapy–Naive HIV-Infected Adults Enrolled in Adult Clinical Trials Group Studies

Science.gov (United States)

Tassiopoulos, Katherine; Landay, Alan; Collier, Ann C.; Connick, Elizabeth; Deeks, Steven G.; Hunt, Peter; Lewis, Dorothy E.; Wilson, Cara; Bosch, Ronald

2012-01-01

Background Individuals infected with human immunodeficiency virus (HIV) have higher risk than HIV-negative individuals for diseases associated with aging. T-cell senescence, characterized by expansion of cells lacking the costimulatory molecule CD28, has been hypothesized to mediate these risks. Methods We measured the percentage of CD28−CD4+ and CD8+ T cells from HIV-infected treatment-naive adults from 5 Adult Clinical Trials Group (ACTG) antiretroviral therapy (ART) studies and the ALLRT (ACTG Longitudinal Linked Randomized Trials) cohort, and from 48 HIV-negative adults. Pretreatment and 96-week posttreatment %CD28− cells were assessed using linear regression for associations with age, sex, race/ethnicity, CD4 count, HIV RNA, ART regimen, and hepatitis C virus (HCV) infection. Results In total, 1291 chronically HIV-infected adults were studied. Pretreatment, lower CD4 count was associated with higher %CD28−CD4+ and %CD28−CD8+ cells. For CD8+ cells, younger age and HCV infection were associated with a lower %CD28−. ART reduced %CD28− levels at week 96 among virally suppressed individuals. Older age was strongly predictive of higher %CD28−CD8+. Compared to HIV-uninfected individuals, HIV-infected individuals maintained significantly higher %CD28−. Conclusions Effective ART reduced the proportion of CD28− T cells. However, levels remained abnormally high and closer to levels in older HIV-uninfected individuals. This finding may inform future research of increased rates of age-associated disease in HIV-infected adults. PMID:22448010

Gibberellic acid alleviates cadmium toxicity by reducing nitric oxide accumulation and expression of IRT1 in Arabidopsis thaliana

Energy Technology Data Exchange (ETDEWEB)

Zhu, Xiao Fang [State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058 (China); Jiang, Tao [Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou 310058 (China); Wang, Zhi Wei [State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058 (China); Lei, Gui Jie [Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou 310058 (China); Shi, Yuan Zhi [The Key Laboratory of Tea Chemical Engineering, Ministry of Agriculture, Yunqi Road 1, Hangzhou 310008 (China); Li, Gui Xin, E-mail: guixinli@zju.edu.cn [College of Agronomy and Biotechnology, Zhejiang University, Hangzhou 310058 (China); Zheng, Shao Jian [State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058 (China); Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou 310058 (China)

2012-11-15

Highlights: Black-Right-Pointing-Pointer Cd reduces endogenous GA levels in Arabidopsis. Black-Right-Pointing-Pointer GA exogenous applied decreases Cd accumulation in plant. Black-Right-Pointing-Pointer GA suppresses the Cd-induced accumulation of NO. Black-Right-Pointing-Pointer Decreased NO level downregulates the expression of IRT1. Black-Right-Pointing-Pointer Suppressed IRT1 expression reduces Cd transport across plasma membrane. - Abstract: Gibberellic acid (GA) is involved in not only plant growth and development but also plant responses to abiotic stresses. Here it was found that treating the plants with GA concentrations from 0.1 to 5 {mu}M for 24 h had no obvious effect on root elongation in the absence of cadmium (Cd), whereas in the presence of Cd{sup 2+}, GA at 5 {mu}M improved root growth, reduced Cd content and lipid peroxidation in the roots, indicating that GA can partially alleviate Cd toxicity. Cd{sup 2+} increased nitric oxide (NO) accumulation in the roots, but GA remarkably reduced it, and suppressed the up-regulation of the expression of IRT1. In contrary, the beneficial effect of GA on alleviating Cd toxicity was not observed in an IRT1 knock-out mutant irt1, suggesting the involvement of IRT1 in Cd{sup 2+} absorption. Furthermore, the GA-induced reduction of NO and Cd content can also be partially reversed by the application of a NO donor (S-nitrosoglutathione [GSNO]). Taken all these together, the results showed that GA-alleviated Cd toxicity is mediated through the reduction of the Cd-dependent NO accumulation and expression of Cd{sup 2+} uptake related gene-IRT1 in Arabidopsis.

Effect of different N fertilizer forms on antioxidant capacity and grain yield of rice growing under Cd stress

Energy Technology Data Exchange (ETDEWEB)

Jalloh, Mohamed Alpha; Chen Jinghong; Zhen Fanrong [Department of Agronomy, Huajiachi Campus, Zhejiang University, Hangzhou 310029 (China); Zhang Guoping [Department of Agronomy, Huajiachi Campus, Zhejiang University, Hangzhou 310029 (China)], E-mail: zhanggp@zju.edu.cn

2009-03-15

Cadmium contamination in soil has become a serious issue in sustainable agriculture production and food safety. A pot experiment was conducted to study the influence of four N fertilizer forms on grain yield, Cd concentration in plant tissues and oxidative stress under two Cd levels (0 and 100 mg Cd kg{sup -1} soil). The results showed that both N form and Cd stress affected grain yield, with urea-N and NH{sub 4}{sup +}-N treatments having significantly higher grain yields, and Cd addition reducing yield. NO{sub 3}{sup -}-N and NH{sub 4}{sup +}-N treated plants had the highest and lowest Cd concentration in plant tissues, respectively. Urea-N and NH{sub 4}{sup +}-N treatments had significantly higher N accumulation in plant tissues than other two N treatments. Cd addition caused a significant increase in leaf superoxide dismutase (SOD) and peroxidase (POD) activities for all N treatments, except for NO{sub 3}{sup -}-N treatment, with urea-N and NH{sub 4}{sup +}-N treated plants having more increase than organic-N treated ones. The results indicated that growth inhibition, yield reduction and Cd uptake of rice plants in response to Cd addition varied with the N fertilizer form.

Cd induced redistribution of elements within leaves of the Cd/Zn hyperaccumulator Thlaspi praecox as revealed by micro-PIXE

International Nuclear Information System (INIS)

Pongrac, Paula; Vogel-Mikus, Katarina; Vavpetic, Primoz; Tratnik, Janja; Regvar, Marjana; Simcic, Jurij; Grlj, Natasa; Pelicon, Primoz

2010-01-01

A detailed localisation of elements within leaf tissues of hydroponically grown Cd/Zn hyperaccumulator Thlaspi praecox (Brassicaceae) was determined by micro-PIXE at Jozef Stefan Institute (Ljubljana, Slovenia) in order to study accumulation patterns of Cd and other elements in the case of a single metal (Cd) pollution. Plants were treated with increasing concentrations of Cd in the solution (0 (control), 1, 10 and 100 μM). As expected, concentration of Cd in the leaves gradually increased with Cd concentration in the solution. In order to reveal the main Cd storage compartment space within the leaves a relative element distribution (pool) was calculated based on concentrations of elements in specific leaf tissues and their weight portions. Where present at detectable levels, Cd accumulated in the epidermal tissues (at 10 μM), but the contribution of epidermal pool decreased with increasing Cd concentration in solution (at 100 μM). The opposite was observed for the mesophyll pool. In addition, in Cd treated plants, a significant decrease in mesophyll Fe pool and an increase in the epidermal Fe pool were observed. Similar effect was seen for Mn pool at 100 μM Cd treatment accompanied by increasing Zn epidermal pool with increasing Cd in nutrient solution. Altogether these results indicate repartitioning of essential mesophyll cation pools (e.g., Fe, Mn and possibly Zn) when increasing Cd contents, that are instead more intensively stored in the epidermal cells. These results confirmed micro-PIXE as effective and powerful technique providing essential information on metal localisation, repartitioning and major elemental stores in plants on the tissue levels that were not accessible using classical analytical techniques and thus complementing our current understanding of plant metal tolerance mechanisms as a whole.

Performances of Water Management, Foliage Dressing, and Variation Screening in Controlling the Accumulation of As and Cd and Maintaining the Concentrations of Essential Elements in the Grains of Rice Plant

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Lei Lei

2018-03-01

Full Text Available This study was conducted to understand why and how the technologies of variety screening, foliar dressing, and water management can reduce As/Cd accumulation and affect the concentrations of essential elements in different rice plants. In Trial I (variety screening, the grain As and Cd concentrations in Zhongguyou1361 variety (P3 were both lower than their individual National Food Hygiene Standard of China (NFHSC under insufficient field drying condition. The P3 also had a relatively high yield and high essential element contents among 15 selected rice varieties. In Trial II (foliar dressing, selenite foliar spray showed a better ability than silicate to reduce the grain As content in Guangliangyou1128 variety (P1. However, spraying Se and Si onto the Fengliangyou1 variety (P2 both showed a limited effect on the grain As and Cd contents, suggesting a different effect of Se on grain As content in various rice varieties. The insufficient field drying in Trial II resulted in the grain Cd content being lower but the grain As content being higher than their individual NFHSC in both P1 and Fengliangyou1 (P2 varieties. Se or Si did not affect the yields and the grain contents of most essential elements in P1 and P2. In Trial III (water management, increasing field drying time enhanced the Cd content but reduced the As content in the grains of P1, P2, and P3, and maintained their yields. Similar to the results of Trial II, the changes in soil pH, organic matter concentration and elemental available concentrations could hardly be used to explain why the contents of corresponding essential elements kept approximately constant in the grains of different rice varieties. Foliar dressing with selenite combined with water regulation can simultaneously reduce the As and Cd contents, and maintain the yields and the essential element contents in the grains of rice plants cultivated in As− and Cd− contaminated soil.

Expression of zinc and cadmium responsive genes in leaves of willow (Salix caprea L.) genotypes with different accumulation characteristics

International Nuclear Information System (INIS)

Konlechner, Cornelia; Türktaş, Mine; Langer, Ingrid; Vaculík, Marek; Wenzel, Walter W.; Puschenreiter, Markus; Hauser, Marie-Theres

2013-01-01

Salix caprea is well suited for phytoextraction strategies. In a previous survey we showed that genetically distinct S. caprea plants isolated from metal-polluted and unpolluted sites differed in their zinc (Zn) and cadmium (Cd) tolerance and accumulation abilities. To determine the molecular basis of this difference we examined putative homologues of genes involved in heavy metal responses and identified over 200 new candidates with a suppression subtractive hybridization (SSH) screen. Quantitative expression analyses of 20 genes in leaves revealed that some metallothioneins and cell wall modifying genes were induced irrespective of the genotype's origin and metal uptake capacity while a cysteine biosynthesis gene was expressed constitutively higher in the metallicolous genotype. The third and largest group of genes was only induced in the metallicolous genotype. These data demonstrate that naturally adapted woody non-model species can help to discover potential novel molecular mechanisms for metal accumulation and tolerance. -- Highlights: ► The transcriptional Zn/Cd response of the willow Salix caprea was quantified. ► Two genotypes from a highly contaminated and a control environment were compared. ► In addition to candidate genes an SSH library revealed over 200 metal induced genes. ► Constitutive upregulation and isolate-specific induction of genes were revealed. ► Willows adapt to environmental Zn/Cd contamination on the transcriptional level. -- Expression analyzes reveal different responses to Cd and Zn exposure of S. caprea genotypes with different heavy metal accumulation abilities

Assessment of cadmium accumulation, toxicity, and tolerance in Brassicaceae and Fabaceae plants--implications for phytoremediation.

Science.gov (United States)

Anjum, Naser A; Umar, Shahid; Iqbal, Muhammad

2014-09-01

This study, based on a greenhouse pot culture experiment conducted with 15-day-old rapeseed (Brassica campestris L. cv. Pusa Gold; family Brassicaceae) and moong bean (Vigna radiata L. Wilczek cv. Pusa Ratna; family Fabaceae) plants treated with cadmium (Cd) concentrations (0, 50, and 100 mg kg(-1) soil), investigates their potential for Cd accumulation and tolerance, and dissects the underlying basic physiological/biochemical mechanisms. In both species, plant dry mass decreased, while Cd concentration of both root and shoot increased with increase in soil Cd. Roots harbored a higher amount of Cd (vs. shoot) in B. campestris, while the reverse applied to V. radiata. By comparison, root Cd concentration was higher in B. campestris than in V. radiata. The high Cd concentrations in B. campestris roots and V. radiata shoots led to significant elevation in oxidative indices, as measured in terms of electrolyte leakage, H2O2 content, and lipid peroxidation. Both plants displayed differential adaptation strategies to counteract the Cd burden-caused anomalies in their roots and shoots. In B. campestris, increasing Cd burden led to a significantly decreased reduced glutathione (GSH) content but a significant increase in activities of GSH reductase (GR), GSH peroxidase (GPX), and GSH sulfotransferase (GST). However, in V. radiata, increasing Cd burden caused significant increase in GSH content and GR activity, but a significant decline in activities of GPX and GST. Cross talks on Cd burden of tissues and the adapted Cd tolerance strategies against Cd burden-accrued toxicity indicated that B. campestris and V. radiata are good Cd stabilizer and Cd extractor, respectively, wherein a fine tuning among the major components (GR, GPX, GST, GSH) of the GSH redox system helped the plants to counteract differentially the Cd load-induced anomalies in tissues. On the whole, the physiological/biochemical characterization of the B. campestris and V. radiata responses to varying Cd

Trace element concentrations in higher fungi

International Nuclear Information System (INIS)

Byrne, A.R.; Ravnik, V.; Kosta, L.

1976-01-01

The concentrations of ten trace elements, As, Br, Cd, Cu, Hg, I, Mn, Se, Zn and V, have been determined in up to 27 species of higher fungi from several sites in Slovenia, Yugoslavia. Analyses were based on destructive neutron activation techniques. Data are presented and compared with the concentrations found in soils. Previously values were non-existent or scanty for these elements, so that the data represent typical levels for basidiomycetes. In addition to confirming high levels of mercury in many species, the survey also found that cadmium is accumulated to a surprising extent by most fungi, the average value being 5 ppm. Among other accumulations found was bromine by the genus Amanita, and selenium by edible Boletus. Correlation analysis between all pairs of trace elements gave values for r of from 0.75 to 0.43 for 7 pairs (Cu and Hg, 0.75; Se and As, 0.69). As well as these features of biochemical interest, the values found and the pattern of accumulation suggest potential uses of fungi in environmental studies

Comparing heavy metals accumulation potential in natural vegetation and soil adjoining wastewater canal

International Nuclear Information System (INIS)

Aurangzeb, N.; Irshad, M.; Hussain, F.; Mahmood, Q.

2011-01-01

Heavy metal (HM) pollution of waters, soils and vegetation is a major ecological problem that needs to be investigated. The present study involved the collection of soil samples and natural vegetations (Tribilas terristris, Lepia nodiflora, Amaranthus viridis, Heliotropium euoropeum, Coronopis didymus, Cynodon ductylon, Chenopodium murale and Eclipta alba) from the vicinity of wastewater canal and subsequent analysis for their HM concentrations. Results showed that HM concentrations varied within the species of vegetation and type of metal analyzed. The order of vegetation for metal concentrations was A. viridis > E. alba > H. euoropeum > L. nodiflora > C. murale > C. didymus > C. ductylon > T. terristris. Metals prevailed in plants in the decreasing order of Fe > Mn > Zn > Pb > Cr > Cu > Cd, irrespective of the vegetation. Metal prevalence in soils was in the order of Fe > Mn > Cd > Cr > Pb > Zn > Cu. Samples near canal were found with higher level of Mn, Pb and Zn as compared to soil away from canal water. Distant sampling gave higher accumulation of Cd, Cr, Cu and Fe as compared to the soil nearby wastewater. The analyzed species of HM in the soils and plants may indicate the variability of their composition in wastewater. (author)

Evaluating Insects as Bioindicators of Heavy Metal Contamination and Accumulation near Industrial Area of Gujrat, Pakistan.

Science.gov (United States)

Azam, Iqra; Afsheen, Sumera; Zia, Ahmed; Javed, Muqaddas; Saeed, Rashid; Sarwar, Muhammad Kaleem; Munir, Bushra

2015-01-01

To study the accumulation and contamination of heavy metals (i.e., Cd, Cr, Cu, Ni, and Zn) in soil, air, and water, few insect species were assayed as ecological indicators. Study area comes under industrial zone of district Gujrat of Punjab, Pakistan. Insects used as bioindicators included a libellulid dragonfly (Crocothemis servilia), an acridid grasshopper (Oxya hyla hyla), and a nymphalid butterfly (Danaus chrysippus) near industrial zone of Gujrat. Accumulation of Cd was highest in insect species followed by Cu, Cr, Zn, and Ni at p Lepidoptera. The total metal concentrations in insects were pointed significantly higher at sites S3 (Mid of HalsiNala), S9 (End of HalsiNala), and S1 (Start of HalsiNala), whereas lowest value was detected at site S6 (Kalra Khasa) located far from industrial area. HACA indicates that these insect groups are potential indicators of metal contamination and can be used in biomonitoring.

In vivo and in vitro cadmium accumulation during the moult cycle of the male shore crab Carcinus maenas-interaction with calcium metabolism

Energy Technology Data Exchange (ETDEWEB)

Norum, Ulrik [Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark)]. E-mail: ulrik@biology.sdu.dk; Bondgaard, Morten [Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark); Pedersen, Thomas V. [Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark); Bjerregaard, Poul [Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark)

2005-03-25

The effect of moult stage on cadmium accumulation and distribution was investigated in vivo in male shore crabs Carcinus maenas exposed to 1 mg Cd l{sup -1} for 7 days. The accumulation of cadmium in all tissues examined was markedly higher in postmoult (A{sub 1-2} and B{sub 1-2}) compared to intermoult (C{sub 1}, C{sub 3} and C{sub 4}) and premoult (D{sub 0-3}). In addition, elevated levels of cadmium were found in gills of late premoult (D{sub 2-3}) animals. The total amount of cadmium accumulated in the tissues (haemolymph, gills, midgut gland and muscle) increased from 43 {mu}g Cd in early premoult (D{sub 0-1}) to 391 {mu}g Cd in late postmoult (B{sub 1-2}). Gills and midgut gland were the primary cadmium accumulating tissues in C{sub 4}-intermoult and premoult (D{sub 0-3}); in early postmoult (A{sub 1-2}) haemolymph and midgut gland were the main cadmium containing tissues, while midgut gland dominated in late postmoult (B{sub 1-2}) and early intermoult (C{sub 1} and C{sub 3}). A detailed account of calcium distribution in haemolymph, gills, midgut gland, muscle and exoskeleton during the moult cycle is presented. Mechanistic links between cadmium and calcium uptake in posterior gills of C{sub 4}-intermoult and early postmoult (A{sub 1-2}) crabs were explored using an in vitro gill perfusion technique. Calcium and cadmium influxes were markedly higher in postmoult compared to intermoult. No differences between intermoult and postmoult effluxes were found for either calcium or cadmium. From intermoult to postmoult net influx increased from 2.4 to 29 {mu}mol Ca{sup 2+} g{sup -1} ww{sub gill} h{sup -1} and from 0.24 to 25 nmol Cd{sup 2+} g{sup -1} ww{sub gill} h{sup -1}. The results indicate that the postmoult increase in cadmium influx is due to increased active transport of cadmium, at least partly, by accidental uptake via calcium transporting proteins. The in vitro net influx rates corresponded accurately to the observed in vivo accumulation of both cadmium

Evaluation of the tolerance of three cultivars of barley to Zn, Cd or Cr in a growth chamber experiment

Directory of Open Access Journals (Sweden)

González A.

2013-04-01

Full Text Available To evaluate the tolerance of three cultivars of barley for the phytoremediation of soils contaminated by metals, a growth chamber experiment with plants exposed to increasing concentrations of Zn, Cd and Cr was conducted. Growth parameters, chlorophyll content and chlorophyll fluorescence were measured at 15 and 29 days after treatment application. Metal concentration in the plant was also measured. In all cases, the amount of metal accumulated in the plant increased by increasing the concentration of the applied metal. Chlorophyll content and chlorophyll fluorescence were higher in the first sampling indicating the negative effect on these parameters of the highest metal concentrations. Cr treatments affected significantly plant growth. Height and dry weights plants were significantly lower (p <0.05 than those treated with Zn and Cd. Physiological parameters measured and water content were also lower in plants treated with Cr. Plaisant and Pedrezuela varieties accumulated more Zn and Cd than Reinette, which accumulated greater amount of Cr than the other two cultivars. This fact shows the interest in selecting the most tolerant varieties when using a crop for phytoremediation of contaminated soils.

18F-FAC PET selectively images hepatic infiltrating CD4 and CD8 T cells in a mouse model of autoimmune hepatitis.

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Salas, Jessica R; Chen, Bao Ying; Wong, Alicia; Cheng, Donghui; Van Arnam, John S; Witte, Owen N; Clark, Peter M

2018-04-26

Immune cell-mediated attack on the liver is a defining feature of autoimmune hepatitis and hepatic allograft rejection. Despite an assortment of diagnostic tools, invasive biopsies remain the only method for identifying immune cells in the liver. We evaluated whether PET imaging with radiotracers that quantify immune activation ( 18 F-FDG and 18 F-FAC) and hepatocyte biology ( 18 F-DFA) can visualize and quantify hepatic infiltrating immune cells and hepatocyte inflammation, respectively, in a preclinical model of autoimmune hepatitis. Methods: Mice treated with Concanavalin A (ConA) to induce a model of autoimmune hepatitis or vehicle were imaged with 18 F-FDG, 18 F-FAC, and 18 F-DFA PET. Immunohistochemistry, digital autoradiography, and ex vivo accumulation assays were used to localize areas of altered radiotracer accumulation in the liver. For comparison, mice treated with an adenovirus to induce a viral hepatitis or vehicle were imaged with 18 F-FDG, 18 F-FAC, and 18 F-DFA PET. 18 F-FAC PET was performed on mice treated with ConA, and vehicle or dexamethasone. Biopsy samples of patients suffering from autoimmune hepatitis were immunostained for deoxycytidine kinase (dCK). Results: Hepatic accumulation of 18 F-FDG and 18 F-FAC was 173% and 61% higher, respectively, and hepatic accumulation of 18 F-DFA was 41% lower in a mouse model of autoimmune hepatitis compared to control mice. Increased hepatic 18 F-FDG accumulation was localized to infiltrating leukocytes and inflamed sinusoidal endothelial cells, increased hepatic 18 F-FAC accumulation was concentrated in infiltrating CD4 and CD8 cells, and decreased hepatic 18 F-DFA accumulation was apparent in hepatocytes throughout the liver. In contrast, viral hepatitis increased hepatic 18 F-FDG accumulation by 109% and decreased hepatic 18 F-DFA accumulation by 20% but had no effect on hepatic 18 F-FAC accumulation (non-significant 2% decrease). 18 F-FAC PET provided a non-invasive biomarker of the efficacy of

Bone marrow-derived CD13+ cells sustain tumor progression

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Dondossola, Eleonora; Corti, Angelo; Sidman, Richard L; Arap, Wadih; Pasqualini, Renata

2014-01-01

Non-malignant cells found within neoplastic lesions express alanyl (membrane) aminopeptidase (ANPEP, best known as CD13), and CD13-null mice exhibit limited tumor growth and angiogenesis. We have recently demonstrated that a subset of bone marrow-derived CD11b+CD13+ myeloid cells accumulate within neoplastic lesions in several murine models of transplantable cancer to promote angiogenesis. If these findings were confirmed in clinical settings, CD11b+CD13+ myeloid cells could become a non-malignant target for the development of novel anticancer regimens. PMID:25339996

Influence of electrical conductivity on the phytoremediation of contaminated soils to Cd 2+ and Zn 2+

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Maryam Salimi

2012-01-01

Conclusions: Results showed that high EC levels of irrigation water increased Cd accumulation and decreased Zn accumulation in the shoots. The presence of high EC levels in irrigation water negatively affected biomass production by plants. Chlorine ion (Cl- had a positive influence on Cd accumulation in the harvestable parts of the plant.

Modulation of CD11c+ lung dendritic cells in respect to TGF-β in experimental pulmonary fibrosis.

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Chakraborty, Kaustav; Chatterjee, Soumya; Bhattacharyya, Arindam

2017-09-01

Idiopathic pulmonary fibrosis (IPF) is a deadly, progressive lung disease with very few treatment options till now. Bleomycin-induced pulmonary fibrosis (BIPF) is a commonly used mice model in IPF research. TGF-β1 has been shown to play a key role in pulmonary fibrosis (PF). Dendritic cell (DC) acts as a bridge between innate and adaptive immune systems. The coexistence of chronic inflammation sustained by mature DCs with fibrosis suggests that inflammatory phenomenon has key importance in the pathogenesis of pulmonary fibrosis. Here, we investigated the modulation of DCs phenotypic maturation, accumulation in lung tissue, and expression of other lung DC subsets in respect to TGF-β in PF. First, we established BIPF model in mice and blocked TGF-β expression by the use of inhibitor SB431542. Accumulation of lung CD11c+ DCs is significantly higher in both inflammatory and fibrotic phases of the disease but that percentages got reduced in the absence of TGF-β. TGF-β initiates up-regulation of costimulatory molecules CD86 and CD80 in the inflammatory phases of the disease but not so at fibrotic stage. Expression of lung DC subset CD11c+CD103+ is significantly increased in inflammatory phase and also in fibrotic phase of BIPF. Blocking of TGF-β causes decreased expression of CD11c+CD103+ DCs. Another important lung DC subset CD11c+CD11b+ expression is suppressed by the absence of TGF-β after bleomycin administration. CD11c+CD103+ DCs might have anti-inflammatory as well as anti-fibrotic nature in PF. All these data demonstrate differential modulation of CD11c+ lung DCs by TGF-β in experimental PF. © 2017 International Federation for Cell Biology.

Surface binding and uptake of cadmium (Cd2+) by LLC-PK1 cells on permeable membrane supports

International Nuclear Information System (INIS)

Prozialeck, W.C.; Lamar, P.C.

1993-01-01

Recent studies have shown that Cd 2+ has relatively specific damaging effects on cell-cell junctions in the renal epithelial cell line, LLC-PK 1 . The objective of the present studies was to examine the surface binding and uptake of Cd 2+ by LLC-PK 1 cells in relation to the disruption of cell-cell junctions. LLC-PK 1 cells on Falcon Cell Culture Inserts were exposed to CdCl 2 containing trace amounts of 109 Cd 2+ from either the apical or the basolateral compartments, and the accumulation of 109 Cd 2+ was monitored for up to 8 h. The integrity of cell-cell junctions was assessed by monitoring the transepithelial electrical resistance. The results showed that the cells accumulated 3-4 times more Cd 2+ from the basolateral compartment than from the apical compartment. The accumulation of Cd 2+ from the basolateral compartment occurred in two phases: a rapid, exponential phase that occurred in 1-2 h and coincided with a decrease in transepithelial resistance, and a slower, linear phase that continued for 6-8 h. The Cd 2+ that accumulated during the rapid phase was easily removed by washing the cells in EGTA, indicating that most of it was bound to sites on the cell surface. By contrast, most of the Cd 2+ that accumulated during the slower phase could not be removed by EGTA, indicating that it had been taken up by the cells. Additional studies showed that the rapid phase of Cd 2+ accumulation was enhanced when Ca 2+ was present at low concentrations (0.1 mM), and was greatly reduced when Ca 2+ was present at high concentrations (10 mM). These results suggest that ld 2+ damages the junctions between LLC-PK 1 cells by interacting with Ca 2+ -sensitive sites on the basolateral cell surface. (orig.)

Response of lettuce to Cd-enriched water and irrigation frequencies ...

African Journals Online (AJOL)

Also, shoot Cd content showed a significant positive correlation with the final accumulated Cd concentration of soil and was expressed by a plateau model under the dry irrigation regime and linear models at other irrigation intervals. Overall, shoot Cd concentration was predicted by using a simple linear regression model ...

Heavy Metal Contents of Municipal and Rural Dumpsite Soils and Rate of Accumulation by Carica papaya and Talinum triangulare in Uyo, Nigeria

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G. A. Ebong

2008-01-01

Full Text Available Dumpsites in Uyo and most cities in Nigeria are used nutrients rich soils for cultivating fruits and vegetables without regards to the risk of toxic metal pollution by the wastes. This development necessitated the research on the assessment of the impact of municipal and rural dumpsites on the metal levels of the underlying soils, the relationship between the dumpsite- soil metal content and the rate of bio-accumulation by plants, the effect of plant specie and plant part on the rate of metal uptake. Atomic absorption spectrophotometer was employed for the analysis of the samples and results obtained from municipal dumpsite soil indicated the following mean concentrations: Fe, 1711.20 μg/g; Pb, 43.28 ug/g; Zn, 88.34 ug/g; Ni, 12.18 ug/g; Cd, 14.10 ug/g and Cu, 56.33 ug/g. These concentrations were relatively higher than the following concentrations: Fe, 1016.98 ug/g; Pb, 18.57 ug/g; Zn, 57.90 ug/g; Ni, 7.98 ug/g; Cd, 9.25 ug/g and Cu, 33.70 ug/g recorded for the rural dumpsite soil. Consequently, plants grown on municipal dumpsites soil accumulated higher concentrations of the metals than those on rural dumpsites. Results obtained from this study also revealed that plants grown on dumpsite soils bio-accumulated higher metal concentrations than their counterparts obtained from normal agricultural soils. The ability of plants to bioaccumulate these metals were also observed as being different from one plant to the other and from one plant parts to the other. And apart from Fe and Zn which recorded higher concentrations in the leaves of the plants studied, other metals recorded higher concentrations in the roots. The general results obtained revealed that the levels of Cd in dumpsite-soil were above the standard while the levels of Cd and Pb in plants were also above the recommended levels in plants. The implications of these high concentrations of these metals in soil and plants have been discussed. Some useful recommendations on the proper

Heavy metals toxicity after acute exposure of cultured renal cells. Intracellular accumulation and repartition

International Nuclear Information System (INIS)

Khodja, Hicham; Carriere, Marie; Avoscan, Laure; Gouget, Barbara

2005-01-01

Lead (Pb), cadmium (Cd) and uranium (U) present no known biological function but are toxic in various concentration ranges. Pb and Cd lead generally to nephrotoxicity consisting in proximal renal tubular dysfunction and accumulation while U has been reported to induce chemical kidney toxicity, functional and histological damages being as well mainly observed in proximal tubule cells. This work address the question of Cd, Pb, and U cytotoxicity, intracellular accumulation and repartition after acute intoxication of renal proximal tubule epithelial cells. After cells exposure to different concentrations of metals for various times, morphological changes were observed and intracellular concentrations and distributions of toxic metals were specified by PIXE coupled to RBS. Cell viability, measured by biochemical tests, was used as toxicity indicator. A direct correlation between cytotoxicity and intracellular accumulation in renal epithelial cells have been established. Finally, intracellular Pb and U localizations were detected while Cd was found to be uniformly distributed in renal cells. (author)

Differential accumulation of heavy metals in the sea anemone Anthopleura elegantissima as a function of symbiotic state

International Nuclear Information System (INIS)

Mitchelmore, Carys L.; Alan Verde, E.; Ringwood, Amy H.; Weis, Virginia M.

2003-01-01

The accumulation of metals by the North American Pacific Coast temperate sea anemone Anthopleura elegantissima, and its dinoflagellate-algal symbiont Symbiodinium muscatinei was examined following laboratory metal exposures. Both, naturally occurring symbiotic and symbiont-free (aposymbiotic) anemones were used in this study to investigate differences in metal uptake due to the symbiotic state of the animal. The effects of metal exposures on the anemone-algal symbiosis were determined using measures of algal cell density and mitotic index (MI). Anemones were exposed to either cadmium, copper, nickel or zinc chloride (0, 10, 100 μg l -1 for Cd, Cu and Ni; 0, 100, 1000 μg l -1 for Zn) for 42 days followed by a 42-day recovery period in ambient seawater. Anemones were analyzed for metal content using inductively coupled plasma mass spectroscopy (ICP-MS) at various time points during the study. Symbiotic anemones accumulated Cd, Ni and Zn to a greater extent than aposymbiotic anemones. A dramatically different pattern of Cu accumulation was observed, with aposymbiotic anemones accumulating higher levels than symbiotic anemones. Following recovery in ambient seawater, all tissue metal levels were reduced to near pre-exposure control levels in most cases. No changes in algal cell density or MI were observed in symbiotic anemone tentacle clips at any dose or time point in the Cd and Cu exposures. However, significant reductions in algal cell densities were observed in the Ni-exposed and some Zn-exposed animals, although levels returned to control values following recovery. There were no changes in mitotic index (MI) following Ni or Zn exposures. These results demonstrate that the extent of heavy metal accumulation depends upon cnidarian symbiotic state and the heavy metal in question

Uptake and loss of dissolved 109Cd and 75Se in estuarine macroinvertebrates.

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Alquezar, Ralph; Markich, Scott J; Twining, John R

2007-04-01

Semaphore crabs (Heloecius cordiformis), soldier crabs (Mictyris platycheles), ghost shrimps (Trypaea australiensis), pygmy mussels (Xenostrobus securis), and polychaetes (Eunice sp.), key benthic prey items of predatory fish commonly found in estuaries throughout southeastern Australia, were exposed to dissolved (109)Cd and (75)Se for 385 h at 30 k Bq/l (uptake phase), followed by exposure to radionuclide-free water for 189 h (loss phase). The whole body uptake rates of (75)Se by pygmy mussels, semaphore crabs and soldier crabs were 1.9, 2.4 and 4.1 times higher than (109)Cd, respectively. There were no significant (P>0.05) differences between the uptake rates of (75)Se and (109)Cd for ghost shrimps and polychaetes. The uptake rates of (109)Cd and (75)Se were highest in pygmy mussels; about six times higher than in soldier crabs for (109)Cd and in polychaetes for (75)Se - the organisms with the lowest uptake rates. The loss rates of (109)Cd and (75)Se were highest in semaphore crabs; about four times higher than in polychaetes for (109)Cd and nine times higher than in ghost shrimps for (75)Se - the organisms with the lowest loss rates. The loss of (109)Cd and (75)Se in all organisms was best described by a two (i.e. short and a longer-lived) compartment model. In the short-lived, or rapidly exchanging, compartment, the biological half-lives of (75)Se (16-39 h) were about three times greater than those of (109)Cd (5-12h). In contrast, the biological half-lives of (109)Cd in the longer-lived, or slowly exchanging compartment(s), were typically greater (1370-5950 h) than those of (75)Se (161-1500 h). Semaphore crabs had the shortest biological half-lives of both radionuclides in the long-lived compartment, whereas polychaetes had the greatest biological half-life for (109)Cd (5950 h), and ghost shrimps had the greatest biological half-life for (75)Se (1500 h). This study provides the first reported data for the biological half-lives of Se in estuarine decapod

Accumulation of cadmium and zinc in soil and vegetation from long-term application of wastewater

International Nuclear Information System (INIS)

Hill, D.C.; Olson, B.H.; Rigby, M.G.

1981-01-01

The accumulation of Cd and Zn in soils and vegetation irrigated with treated sewage effluents was examined at 3 locations in southern California. The Whittier Narrows site, a groundwater recharge test plot, received secondary effluent through intermittent flooding for approximately 14 years. Fountain Valley, a forested site, was flood irrigated with both primary and secondary effluents for 16 years. The 3 Las Virgenes sites received various amounts of secondary effluent by spray irrigation for 8 years. Elevated levels of Cd and Zn were observed in the upper layers of soil at the Fountain Valley and Whittier Narrows sites. No metal accumulation from wastewater application was found at Las Virgenes. However, Cd was elevated throughout the soil profiles which reflected the Cd-enriched underlying host rock, Monterey Shale. A variety of weed species were examined at the Las Virgenes and Whittier Narrows sites and 4 tree species were studied at the Fountain Valley site. These results indicated that Cd and Zn concentrations in the tissue of most genera paralleled soil levels, but accumulation and exclusion patterns of Cd and Zn can be species dependent and therefore differ at the same site

Iron plaque decreases cadmium accumulation in Oryza sativa L. and serves as a source of iron.

Science.gov (United States)

Sebastian, A; Prasad, M N V

2016-11-01

Cadmium (Cd) contamination occurs in paddy soils; hence it is necessary to reduce Cd content of rice. Application and mode of action of ferrous sulphate in minimizing Cd in rice was monitored in the present study. Pot culture with Indian rice variety Swarna (MTU 7029) was maintained in Cd-spiked soil containing ferrous sulphates, which is expected to reduce Cd accumulation in rice. Responses in rhizosphere pH, root surface, metal accumulation in plant and molecular physiological processes were monitored. Iron plaque was induced on root surfaces after FeSO4 application and the amount of Fe in plaque reduced with increases in Cd in the soil. Rhizosphere pH decreased during plaque formation and became more acidic due to secretion of organic acids from the roots under Cd treatment. Moreover, iron chelate reductase activity increased with Cd treatment, but in the absence of Cd, activity of this enzyme increased in plaque-induced plants. Cd treatment caused expression of OsYSL18, whereas OsYSL15 was expressed only in roots without iron plaque. Fe content of plants increased during plaque formation, which protected plants from Cd-induced Fe deficiency and metal toxicity. This was corroborated with increased biomass, chlorophyll content and quantum efficiency of photo-synthesis among plaque-induced plants. We conclude that ferrous sulphate-induced iron plaque prevents Cd accumulation and Fe deficiency in rice. Iron released from plaque via organic acid mediated dissolution during Cd stress. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

Accumulation of heavy metals in soil-crop systems: a review for wheat and corn.

Science.gov (United States)

Wang, Shiyu; Wu, Wenyong; Liu, Fei; Liao, Renkuan; Hu, Yaqi

2017-06-01

The health risks arising from heavy metal pollution (HMP) in agricultural soils have attracted global attention, and research on the accumulation of heavy metals in soil-plant systems is the basis for human health risk assessments. This review studied the accumulation of seven typical heavy metals-Cd, Cr, As, Pb, Hg, Cu, and Zn-in soil-corn and soil-wheat systems. The findings indicated that, in general, wheat was more likely to accumulate heavy metals than corn. Bioconcentration factor (BCF) of the seven heavy metals in wheat and corn grains decreased exponentially with their average concentrations in soil. The seven heavy metals were ranked as follows, in ascending order of accumulation in corn grains: Pb < Cr < Zn < As < Cu < Cd accumulation in wheat grains, their ranking was as follows: Zn < Pb < Cr < Cu < As < Hg <Cd. The minimum BCFs of Cd, Cr, As, Pb, Hg, Cu, and Zn in corn grains were 0.054, 6.65 × 10 -4 , 7.94 × 10 -4 , 0.0044, 0.028, 0.13, and 0.19, respectively. The corresponding BCFs values for wheat grains were 0.25, 0.0045, 5.42 × 10 -4 , 0.009, 4.03 × 10 -4 , 0.11, and 0.054, respectively.

Role of freeze-thaw cycles and chlorpyrifos insecticide use on diffuse Cd loss and sediment accumulation

Science.gov (United States)

Wang, Fangli; Ouyang, Wei; Hao, Fanghua; Jiao, Wei; Shan, Yushu; Lin, Chunye

2016-06-01

Freeze-thaw cycles are predicted to increase in cold temperate regions. The potential influence of the interactions of freeze-thaw cycles and agrochemicals on the release of Cd into river water is unknown. In this study, the interactions of freeze-thaw cycles and chlorpyrifos (FC) on Cd mobility in soils were analysed. The spatial variability of soil Cd under long-term intensive tillage in a freeze-thaw agro-system was also identified. The temporal variation of sediment Cd was detected based on analysis of the sediment geochemistry. The results showed that FC increased soil Cd mobility, with an increase of approximately 10% in CaCl2-extractable Cd. The increased mobile fractions of water-soluble and exchangeable Cd originated from the decreased fraction of Fe-Mn-oxide-associated Cd and organic matter-bound Cd. The total Cd content in the surface soil followed the zonally decreasing trend of dry land > paddy land > natural land. The Cd concentrations and sedimentation rates of the sediment core generally increased from 1943 to 2013 due to agricultural exploration and farmland irrigation system construction, indicating an increase of the Cd input flux into water. The results provide valuable information about the soil Cd transport response to the influence of climatic and anthropogenic factors in cold intensive agro-systems.

Functional contribution of elevated circulating and hepatic non-classical CD14CD16 monocytes to inflammation and human liver fibrosis.

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Henning W Zimmermann

Full Text Available BACKGROUND: Monocyte-derived macrophages critically perpetuate inflammatory responses after liver injury as a prerequisite for organ fibrosis. Experimental murine models identified an essential role for the CCR2-dependent infiltration of classical Gr1/Ly6C(+ monocytes in hepatic fibrosis. Moreover, the monocyte-related chemokine receptors CCR1 and CCR5 were recently recognized as important fibrosis modulators in mice. In humans, monocytes consist of classical CD14(+CD16(- and non-classical CD14(+CD16(+ cells. We aimed at investigating the relevance of monocyte subpopulations for human liver fibrosis, and hypothesized that 'non-classical' monocytes critically exert inflammatory as well as profibrogenic functions in patients during liver disease progression. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed circulating monocyte subsets from freshly drawn blood samples of 226 patients with chronic liver disease (CLD and 184 healthy controls by FACS analysis. Circulating monocytes were significantly expanded in CLD-patients compared to controls with a marked increase of the non-classical CD14(+CD16(+ subset that showed an activated phenotype in patients and correlated with proinflammatory cytokines and clinical progression. Correspondingly, CD14(+CD16(+ macrophages massively accumulated in fibrotic/cirrhotic livers, as evidenced by immunofluorescence and FACS. Ligands of monocyte-related chemokine receptors CCR2, CCR1 and CCR5 were expressed at higher levels in fibrotic and cirrhotic livers, while CCL3 and CCL4 were also systemically elevated in CLD-patients. Isolated monocyte/macrophage subpopulations were functionally characterized regarding cytokine/chemokine expression and interactions with primary human hepatic stellate cells (HSC in vitro. CD14(+CD16(+ monocytes released abundant proinflammatory cytokines. Furthermore, CD14(+CD16(+, but not CD14(+CD16(- monocytes could directly activate collagen-producing HSC. CONCLUSIONS/SIGNIFICANCE: Our data

Cd-tolerant Suillus luteus: A fungal insurance for pines exposed to Cd

International Nuclear Information System (INIS)

Krznaric, Erik; Verbruggen, Nathalie; Wevers, Jan H.L.; Carleer, Robert; Vangronsveld, Jaco; Colpaert, Jan V.

2009-01-01

Soil metal pollution can trigger evolutionary adaptation in soil-borne organisms. An in vitro screening test showed cadmium adaptation in populations of Suillus luteus (L.: Fr.) Roussel, an ectomycorrhizal fungus of pine trees. Cadmium stress was subsequently investigated in Scots pine (Pinus sylvestris L.) seedlings inoculated with a Cd-tolerant S. luteus, isolated from a heavy metal contaminated site, and compared to plants inoculated with a Cd-sensitive isolate from a non-polluted area. A dose-response experiment with mycorrhizal pines showed better plant protection by a Cd-adapted fungus: more fungal biomass and a higher nutrient uptake at high Cd exposure. In addition, less Cd was transferred to aboveground plant parts. Because of the key role of the ectomycorrhizal symbiosis for tree fitness, the evolution of Cd tolerance in an ectomycorrhizal partner such as S. luteus can be of major importance for the establishment of pine forests on Cd-contaminated soils. - The evolutionary adaptation for higher Cd tolerance in Suillus luteus, an ectomycorrhizal fungus, is of major importance for the amelioration of Cd toxicity in pine trees exposed to high Cd concentrations.

Cd-tolerant Suillus luteus: A fungal insurance for pines exposed to Cd

Energy Technology Data Exchange (ETDEWEB)

Krznaric, Erik [Environmental Biology Group, Centre for Environmental Sciences, Hasselt University, Agoralaan, Gebouw D, 3590 Diepenbeek (Belgium); Verbruggen, Nathalie [Laboratoire de Physiologie et de Genetique Moleculaire des Plantes, Universite Libre de Bruxelles, Campus Plaine, CP242, Bd du Triomphe, 1050 Brussels (Belgium); Wevers, Jan H.L. [Environmental Biology Group, Centre for Environmental Sciences, Hasselt University, Agoralaan, Gebouw D, 3590 Diepenbeek (Belgium); Carleer, Robert [Laboratory of Applied Chemistry, Centre for Environmental Sciences, Hasselt University, Agoralaan, Gebouw D, 3590 Diepenbeek (Belgium); Vangronsveld, Jaco [Environmental Biology Group, Centre for Environmental Sciences, Hasselt University, Agoralaan, Gebouw D, 3590 Diepenbeek (Belgium); Colpaert, Jan V., E-mail: jan.colpaert@uhasselt.b [Environmental Biology Group, Centre for Environmental Sciences, Hasselt University, Agoralaan, Gebouw D, 3590 Diepenbeek (Belgium)

2009-05-15

Soil metal pollution can trigger evolutionary adaptation in soil-borne organisms. An in vitro screening test showed cadmium adaptation in populations of Suillus luteus (L.: Fr.) Roussel, an ectomycorrhizal fungus of pine trees. Cadmium stress was subsequently investigated in Scots pine (Pinus sylvestris L.) seedlings inoculated with a Cd-tolerant S. luteus, isolated from a heavy metal contaminated site, and compared to plants inoculated with a Cd-sensitive isolate from a non-polluted area. A dose-response experiment with mycorrhizal pines showed better plant protection by a Cd-adapted fungus: more fungal biomass and a higher nutrient uptake at high Cd exposure. In addition, less Cd was transferred to aboveground plant parts. Because of the key role of the ectomycorrhizal symbiosis for tree fitness, the evolution of Cd tolerance in an ectomycorrhizal partner such as S. luteus can be of major importance for the establishment of pine forests on Cd-contaminated soils. - The evolutionary adaptation for higher Cd tolerance in Suillus luteus, an ectomycorrhizal fungus, is of major importance for the amelioration of Cd toxicity in pine trees exposed to high Cd concentrations.

Endogenous adenosine produced during hypoxia attenuates neutrophil accumulation: coordination by extracellular nucleotide metabolism.

Science.gov (United States)

Eltzschig, Holger K; Thompson, Linda F; Karhausen, Jorn; Cotta, Richard J; Ibla, Juan C; Robson, Simon C; Colgan, Sean P

2004-12-15

Hypoxia is a well-documented inflammatory stimulus and results in tissue polymorphonuclear leukocyte (PMN) accumulation. Likewise, increased tissue adenosine levels are commonly associated with hypoxia, and given the anti-inflammatory properties of adenosine, we hypothesized that adenosine production via adenine nucleotide metabolism at the vascular surface triggers an endogenous anti-inflammatory response during hypoxia. Initial in vitro studies indicated that endogenously generated adenosine, through activation of PMN adenosine A(2A) and A(2B) receptors, functions as an antiadhesive signal for PMN binding to microvascular endothelia. Intravascular nucleotides released by inflammatory cells undergo phosphohydrolysis via hypoxia-induced CD39 ectoapyrase (CD39 converts adenosine triphosphate/adenosine diphosphate [ATP/ADP] to adenosine monophosphate [AMP]) and CD73 ecto-5'-nucleotidase (CD73 converts AMP to adenosine). Extensions of our in vitro findings using cd39- and cd73-null animals revealed that extracellular adenosine produced through adenine nucleotide metabolism during hypoxia is a potent anti-inflammatory signal for PMNs in vivo. These findings identify CD39 and CD73 as critical control points for endogenous adenosine generation and implicate this pathway as an innate mechanism to attenuate excessive tissue PMN accumulation.

Metal accumulation in the smooth toadfish, Tetractenos glaber, in estuaries around Sydney, Australia

International Nuclear Information System (INIS)

Alquezar, Ralph; Markich, Scott J.; Booth, David J.

2006-01-01

This study determined the metal levels in sediments and tissues of a common estuarine fish, Tetractenos glaber (smooth toadfish), from two metal contaminated and two reference estuaries near Sydney, Australia. Metal levels were highest in sediments and fish from contaminated estuaries. Gonads contained the highest metal levels followed by muscle, gill and liver. Metal accumulation was gender-dependant (e.g. male gonads were >20 times higher in As than females; female gills were >30 times higher than males for Pb). Cadmium, Pb and Ni levels in fish tissues reflected sediment levels, indicating sediment and/or dietary metal uptake. Levels of As, Co, Cd and Pb in gills showed similar patterns to other tissues, suggesting that metals may have been taken up by gills through contaminated water. Similar metal patterns in tissues and sediments suggest more than one uptake pathway. This study indicates that multiple factors influence metal accumulation in fish. - Metal levels in toadfish tissues reflect sediment metal levels and show gender differences

Cadmium tolerance and accumulation characteristics of mature flax, cv. Hermes: Contribution of the basal stem compared to the root

Energy Technology Data Exchange (ETDEWEB)

Douchiche, Olfa, E-mail: olfa.douchiche@hotmail.fr [Laboratory Glyco-MEV EA 4358, IFRMP 23, University of Rouen, 76821 Mont Saint Aignan Cedex (France); Laboratory Biologie et Physiologie Cellulaires Vegetales, Department of Biology, University of Tunis, 1060 Tunis (Tunisia); Chaiebi, Wided [Laboratory Biologie et Physiologie Cellulaires Vegetales, Department of Biology, University of Tunis, 1060 Tunis (Tunisia); Morvan, Claudine, E-mail: claudine.morvan@univ-rouen.fr [Laboratory PBS-UMR 6270 CNRS, FR 3038, University of Rouen, 76821 Mont Saint Aignan Cedex (France)

2012-10-15

Highlights: Black-Right-Pointing-Pointer Cd accumulated in stem bottom part exceeded the defined hyperaccumulator threshold. Black-Right-Pointing-Pointer No toxic symptoms occurred and TI of all growth parameters ranged between 0.7 and 1. Black-Right-Pointing-Pointer The high level of Zn, Mn and Cu may contribute to the absence of chlorosis in stem. Black-Right-Pointing-Pointer Cd/Ca synergistic effect observed in the stem may alleviate Cd toxicity. Black-Right-Pointing-Pointer Hermes variety accumulated more Cd than the other flax varieties ever described. - Abstract: The potential of mature flax plants (cv. Hermes) to tolerate and accumulate cadmium (Cd) was studied to determine which part of the plant would be the key organ for phytoremediation purposes. After 4 month-growth on sand substrate containing 0.1 mM Cd in a greenhouse, the roots and stems were separated and the stems were divided into three parts. The effects of Cd were studied on growth parameters, histology and mineral nutrition. No visible toxic symptoms were observed. Tolerance-index values calculated from growth parameters and nutrients remained relatively high, allowing the development of the plant until maturity and formation of seeds. The roots and bottom stem accumulated the highest quantity of Cd (750 and 360 mg/kg dry matter), values which largely exceeded the threshold defined for hyperaccumulators. On the other hand, basal stem had a high bioconcentration factor (BCF = 32) and translocation factor TF Prime (2.5) but a low TF (0.5), indicating that this basal part would play a major role in phytoremediation (phytostabilization rather than phytorextraction). Therefore, the high tolerance to Cd and accumulation capacity make possible to grow Hermes flax on Cd-polluted soils.

Use of Maize (Zea mays L.) for phytomanagement of Cd-contaminated soils: a critical review.

Science.gov (United States)

Rizwan, Muhammad; Ali, Shafaqat; Qayyum, Muhammad Farooq; Ok, Yong Sik; Zia-Ur-Rehman, Muhammad; Abbas, Zaheer; Hannan, Fakhir

2017-04-01

Maize (Zea mays L.) has been widely adopted for phytomanagement of cadmium (Cd)-contaminated soils due to its high biomass production and Cd accumulation capacity. This paper reviewed the toxic effects of Cd and its management by maize plants. Maize could tolerate a certain level of Cd in soil while higher Cd stress can decrease seed germination, mineral nutrition, photosynthesis and growth/yields. Toxicity response of maize to Cd varies with cultivar/varieties, growth medium and stress duration/extent. Exogenous application of organic and inorganic amendments has been used for enhancing Cd tolerance of maize. The selection of Cd-tolerant maize cultivar, crop rotation, soil type, and exogenous application of microbes is a representative agronomic practice to enhance Cd tolerance in maize. Proper selection of cultivar and agronomic practices combined with amendments might be successful for the remediation of Cd-contaminated soils with maize. However, there might be the risk of food chain contamination by maize grains obtained from the Cd-contaminated soils. Thus, maize cultivation could be an option for the management of low- and medium-grade Cd-contaminated soils if grain yield is required. On the other hand, maize can be grown on Cd-polluted soils only if biomass is required for energy production purposes. Long-term field trials are required, including risks and benefit analysis for various management strategies aiming Cd phytomanagement with maize.

Identification of cadmium-excluding Welsh onion (Allium fistulosum L.) cultivars and their mechanisms of low cadmium accumulation.

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Li, Xuhui; Zhou, Qixing; Wei, Shuhe; Ren, Wenjie

2012-06-01

Screening out cadmium (Cd) excluding cultivars of a crop in agricultural production is an effective way to prohibit Cd entering into food chain. A judging criterion for Cd-excluding cultivars based on food safety was suggested and used in the identification of Cd-excluding welsh onion (Allium fistulosum L.) cultivars. A pot culture experiment was carried out to screen out Cd-excluding cultivars, of which the results were confirmed by plot experiments. The relevant factors of Cd accumulation in the pseudostem were analyzed and used in the correlation analysis aiming to study the low Cd accumulation mechanisms. The concentration of Cd in the pseudostem of welsh onions was 0.08-0.20, 0.18-0.41, and 0.26-0.61 mg/kg fresh weight (FW) under three treatments (1.0, 2.5, and 5.0 mg/kg), respectively. The significant (p onion cultivars, but Cd contamination in soil had little influence on biomass and the contents of soluble sugar, NO(3)(-)-N, and eight other elements in the tested welsh onion cultivars. Two cultivars were identified as Cd-excluding cultivars, mainly because the accumulation of Cd in their pseudostem was only 0.041 ± 0.003 and 0.046 ± 0.002 mg/kg FW, and 0.054 ± 0.001 and 0.066 ± 0.011 mg/kg FW, when growing in plots with Cd concentration of 0.49 and 0.99 mg/kg, respectively. Ribentiegancongwang and Wuyeqi could be identified as Cd-excluding cultivars. Low bioaccumulation factor of the roots was the main mechanism of Cd-excluding welsh onion cultivars.

Impact of two iron(III) chelators on the iron, cadmium, lead and nickel accumulation in poplar grown under heavy metal stress in hydroponics.

Science.gov (United States)

Mihucz, Victor G; Csog, Árpád; Fodor, Ferenc; Tatár, Enikő; Szoboszlai, Norbert; Silaghi-Dumitrescu, Luminiţa; Záray, Gyula

2012-04-15

Poplar (Populus jacquemontiana var. glauca cv. Kopeczkii) was grown in hydroponics containing 10 μM Cd(II), Ni(II) or Pb(II), and Fe as Fe(III) EDTA or Fe(III) citrate in identical concentrations. The present study was designed to compare the accumulation and distribution of Fe, Cd, Ni and Pb within the different plant compartments. Generally, Fe and heavy-metal accumulation were higher by factor 2-7 and 1.6-3.3, respectively, when Fe(III) citrate was used. Iron transport towards the shoot depended on the Fe(III) chelate and, generally, on the heavy metal used. Lead was accumulated only in the root. The amounts of Fe and heavy metals accumulated by poplar were very similar to those of cucumber grown in an identical way, indicating strong Fe uptake regulation of these two Strategy I plants: a cultivar and a woody plant. The Strategy I Fe uptake mechanism (i.e. reducing Fe(III) followed by Fe(II) uptake), together with the Fe(III) chelate form in the nutrient solution had significant effects on Fe and heavy metal uptake. Poplar appears to show phytoremediation potential for Cd and Ni, as their transport towards the shoot was characterized by 51-54% and 26-48% depending on the Fe(III) supply in the nutrient solution. Copyright © 2012 Elsevier GmbH. All rights reserved.

Empty conformers of HLA-B preferentially bind CD8 and regulate CD8+ T cell function.

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Geng, Jie; Altman, John D; Krishnakumar, Sujatha; Raghavan, Malini

2018-05-09

When complexed with antigenic peptides, human leukocyte antigen (HLA) class I (HLA-I) molecules initiate CD8 + T cell responses via interaction with the T cell receptor (TCR) and co-receptor CD8. Peptides are generally critical for the stable cell surface expression of HLA-I molecules. However, for HLA-I alleles such as HLA-B*35:01, peptide-deficient (empty) heterodimers are thermostable and detectable on the cell surface. Additionally, peptide-deficient HLA-B*35:01 tetramers preferentially bind CD8 and to a majority of blood-derived CD8 + T cells via a CD8-dependent binding mode. Further functional studies reveal that peptide-deficient conformers of HLA-B*35:01 do not directly activate CD8 + T cells, but accumulate at the immunological synapse in antigen-induced responses, and enhance cognate peptide-induced cell adhesion and CD8 + T cell activation. Together, these findings indicate that HLA-I peptide occupancy influences CD8 binding affinity, and reveal a new set of regulators of CD8 + T cell activation, mediated by the binding of empty HLA-I to CD8. © 2018, Geng et al.

Mtb-specific CD27low CD4 T cells as markers of lung tissue destruction during pulmonary tuberculosis in humans.

Science.gov (United States)

Nikitina, Irina Yu; Kondratuk, Natalya A; Kosmiadi, George A; Amansahedov, Rasul B; Vasilyeva, Irina A; Ganusov, Vitaly V; Lyadova, Irina V

2012-01-01

Effector CD4 T cells represent a key component of the host's anti-tuberculosis immune defense. Successful differentiation and functioning of effector lymphocytes protects the host against severe M. tuberculosis (Mtb) infection. On the other hand, effector T cell differentiation depends on disease severity/activity, as T cell responses are driven by antigenic and inflammatory stimuli released during infection. Thus, tuberculosis (TB) progression and the degree of effector CD4 T cell differentiation are interrelated, but the relationships are complex and not well understood. We have analyzed an association between the degree of Mtb-specific CD4 T cell differentiation and severity/activity of pulmonary TB infection. The degree of CD4 T cell differentiation was assessed by measuring the percentages of highly differentiated CD27(low) cells within a population of Mtb- specific CD4 T lymphocytes ("CD27(low)IFN-γ(+)" cells). The percentages of CD27(low)IFN-γ+ cells were low in healthy donors (median, 33.1%) and TB contacts (21.8%) but increased in TB patients (47.3%, p76%), but varied in blood (12-92%). The major correlate for the accumulation of CD27(low)IFN-γ(+) cells in blood was lung destruction (r = 0.65, p = 2.7 × 10(-7)). A cutoff of 47% of CD27(low)IFN-γ(+) cells discriminated patients with high and low degree of lung destruction (sensitivity 89%, specificity 74%); a decline in CD27(low)IFN-γ(+)cells following TB therapy correlated with repair and/or reduction of lung destruction (ppulmonary TB. Accumulation of CD27(low)IFN-γ(+) cells in the blood is associated with lung destruction. The findings indicate that there is no deficiency in CD4 T cell differentiation during TB; evaluation of CD27(low)IFN-γ(+) cells provides a valuable means to assess TB activity, lung destruction, and tissue repair following TB therapy.

Transcriptome analysis by cDNA-AFLP of Suillus luteus Cd-tolerant and Cd-sensitive isolates.

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Ruytinx, Joske; Craciun, Adrian R; Verstraelen, Karen; Vangronsveld, Jaco; Colpaert, Jan V; Verbruggen, Nathalie

2011-04-01

The ectomycorrhizal basidiomycete Suillus luteus (L.:Fr.), a typical pioneer species which associates with young pine trees colonizing disturbed sites, is a common root symbiont found at heavy metal contaminated sites. Three Cd-sensitive and three Cd-tolerant isolates of S. luteus, isolated respectively from non-polluted and a heavy metal-polluted site in Limburg (Belgium), were used for a transcriptomic analysis. We identified differentially expressed genes by cDNA-AFLP analysis. The possible roles of some of the encoded proteins in heavy metal (Cd) accumulation and tolerance are discussed. Despite the high conservation of coding sequences in S. luteus, a large intraspecific variation in the transcript profiles was observed. This variation was as large in Cd-tolerant as in sensitive isolates and may help this pioneer species to adapt to novel environments.

The respective effects of soil heavy metal fractions by sequential extraction procedure and soil properties on the accumulation of heavy metals in rice grains and brassicas.

Science.gov (United States)

Xiao, Ling; Guan, Dongsheng; Peart, M R; Chen, Yujuan; Li, Qiqi

2017-01-01

This study was carried out to examine heavy metal accumulation in rice grains and brassicas and to identify the different controls, such as soil properties and soil heavy metal fractions obtained by the Community Bureau of Reference (BCR) sequential extraction, in their accumulation. In Guangdong Province, South China, rice grain and brassica samples, along with their rhizospheric soil, were collected from fields on the basis of distance downstream from electroplating factories, whose wastewater was used for irrigation. The results showed that long-term irrigation using the electroplating effluent has not only enriched the rhizospheric soil with Cd, Cr, Cu, and Zn but has also increased their mobility and bioavailability. The average concentrations of Cd and Cr in rice grains and brassicas from closest to the electroplating factories were significantly higher than those from the control areas. Results from hybrid redundancy analysis (hRDA) and redundancy analysis (RDA) showed that the BCR fractions of soil heavy metals could explain 29.0 and 46.5 % of total eigenvalue for heavy metal concentrations in rice grains and brassicas, respectively, while soil properties could only explain 11.1 and 33.4 %, respectively. This indicated that heavy metal fractions exerted more control upon their concentrations in rice grains and brassicas than soil properties. In terms of metal interaction, an increase of residual Zn in paddy soil or a decrease of acid soluble Cd in the brassica soil could enhance the accumulation of Cd, Cu, Cr, and Pb in both rice grains and brassicas, respectively, while the reducible or oxidizable Cd in soil could enhance the plants' accumulation of Cr and Pb. The RDA showed an inhibition effect of sand content and CFO on the accumulation of heavy metals in rice grains and brassicas. Moreover, multiple stepwise linear regression could offer prediction for Cd, Cu, Cr, and Zn concentrations in the two crops by soil heavy metal fractions and soil properties.

Bioaccumulation and partitioning of cadmium within the freshwater mussel Dreissena polymorpha Pallas. [Using /sup 109/Cd and /sup 115/Cd as tracers

Energy Technology Data Exchange (ETDEWEB)

Bias, R.; Karbe, L. (Hamburg Univ. (Germany, F.R.))

1985-01-01

Kinetics of uptake, partitioning and elimination of cadmium were investigated in experimental studies with the freshwater mussel, Dreissena polymorpha. /sup 109/Cd and /sup 115/Cd were used as tracers. Shells, soft parts and body fluid of the mussel exhibited considerable differences in accumulation and elimination. Accumulation factors up to more than 70,000 were calculated for the periostracum, whereas accumulation factors for the whole mussels ranging up to 3,000 were calculated. The shells bound a great deal of cadmium, but only loosely, and the metal could be readily eliminated after transfer to uncontaminated water. In contrast, no significant amounts of the cadmium incorporated in the soft parts were eliminated. The results indicate that the major portion of cadmium in the soft parts is strongly bound and cannot be eliminated by exchange processes.

Spatio-temporal variation of element accumulation by Moehringia trinervia in a polluted forest ecosystem (South Poland)

International Nuclear Information System (INIS)

Kapusta, Pawel; Szarek-Lukaszewska, Grazyna; Godzik, Barbara

2006-01-01

The aim of this study was to identify factors affecting accumulation of elements by Moehringia trinervia (L.) Clairv. in a forest ecosystem impacted by long-term inflow of air pollution. The concentrations of N, S, Ca, K, Mg, Cd, Cu, Fe, Pb and Zn were determined in plants collected in 1999. In addition, Cd, Cu, Pb and Zn content was compared with measurements from 1984. Soil properties and bulk precipitation chemistry were used as explaining variables. The amount of heavy metals accumulated by M. trinervia depended on the magnitude of industrial emissions, but only Cu and Pb concentrations were clearly related to the distance from the pollution sources. The spatial distribution of Fe content was shaped by habitat conditions, whereas the distributions of Cd and Zn content were unexplained. Among the macronutrients, only Mg uptake was affected by environmental properties: it was lower under high concentrations of soil Cd and Zn. - Accumulation of heavy metals (Cd, Cu, Fe, Pb and Zn) by Moehringia trinervia reflects the impact of both pollutant deposition and soil properties

Spatio-temporal variation of element accumulation by Moehringia trinervia in a polluted forest ecosystem (South Poland)

Energy Technology Data Exchange (ETDEWEB)

Kapusta, Pawel [Department of Ecosystem Studies, Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Cracow (Poland)]. E-mail: pkapusta@comhlan.art.pl; Szarek-Lukaszewska, Grazyna [W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Cracow (Poland); Godzik, Barbara [W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Cracow (Poland)

2006-09-15

The aim of this study was to identify factors affecting accumulation of elements by Moehringia trinervia (L.) Clairv. in a forest ecosystem impacted by long-term inflow of air pollution. The concentrations of N, S, Ca, K, Mg, Cd, Cu, Fe, Pb and Zn were determined in plants collected in 1999. In addition, Cd, Cu, Pb and Zn content was compared with measurements from 1984. Soil properties and bulk precipitation chemistry were used as explaining variables. The amount of heavy metals accumulated by M. trinervia depended on the magnitude of industrial emissions, but only Cu and Pb concentrations were clearly related to the distance from the pollution sources. The spatial distribution of Fe content was shaped by habitat conditions, whereas the distributions of Cd and Zn content were unexplained. Among the macronutrients, only Mg uptake was affected by environmental properties: it was lower under high concentrations of soil Cd and Zn. - Accumulation of heavy metals (Cd, Cu, Fe, Pb and Zn) by Moehringia trinervia reflects the impact of both pollutant deposition and soil properties.

Soluble CD30 and Cd27 levels in patients undergoing HLA antibody-incompatible renal transplantation.

Science.gov (United States)

Hamer, Rizwan; Roche, Laura; Smillie, David; Harmer, Andrea; Mitchell, Daniel; Molostvov, Guerman; Lam, For T; Kashi, Habib; Tan, Lam Chin; Imray, Chris; Fletcher, Simon; Briggs, David; Lowe, David; Zehnder, Daniel; Higgins, Rob

2010-08-01

HLA antibody-incompatible transplantation has a higher risk of rejection when compared to standard renal transplantation. Soluble CD30 (sCD30) has been shown in many, but not all, studies to be a biomarker for risk of rejection in standard renal transplant recipients. We sought to define the value of sCD30 and soluble CD27 (sCD27) in patients receiving HLA antibody-incompatible transplants. Serum taken at different time points from 32 HLA antibody-incompatible transplant recipients was retrospectively assessed for sCD30 and sCD27 levels by enzyme-linked immunosorbent assay (ELISA). This was compared to episodes of acute rejection, post-transplant donor-specific antibody (DSA) levels and 12 month serum creatinine levels. No association was found between sCD27 and sCD30 levels and risk of acute rejection or DSA levels. Higher sCD30 levels at 4-6 weeks post-transplantation were associated with a higher serum creatinine at 12 months. Conclusion patients undergoing HLA antibody-incompatible transplantation are at a high risk of rejection but neither sCD30 (unlike in standard transplantation) nor sCD27 was found to be a risk factor. High sCD30 levels measured at 4-6 weeks post-transplantation was associated with poorer graft function at one year. Copyright © 2010 Elsevier B.V. All rights reserved.

Assessment of tissue-specific accumulation and effects of cadmium in a marine fish fed contaminated commercially produced diet

International Nuclear Information System (INIS)

Dang Fei; Wang Wenxiong

2009-01-01

Commercially produced fish diet is now widely used in fish farming but it often contains elevated levels of cadmium (Cd). However, the adverse effects on fish are poorly understood. In this study, farm-raised marine grunts, Terapon jarbua, were fed Cd-contaminated diet or exposed to waterborne Cd for 4 weeks. Tissue-specific Cd bioaccumulation and its effects were subsequently examined. We found that Cd was accumulated in different fish tissues (digestive tracts, gills or livers). At the end of the exposure, Cd accumulation peaked in the fishes' livers (5.0-6.3 μg g -1 ), followed by the digestive tracts (0.83-3.16 μg g -1 ) and gills (0.27-2.74 μg g -1 ). Endpoints such as the survival rate, specific growth rate, condition factor, and superoxide dismutase activity were not significantly affected by Cd exposure. In contrast, metallothionein (MT) induction and subcellular Cd distribution indicated that there were possible sublethal effects of Cd exposure. MT was induced in response to Cd accumulation, but it returned to the control levels after a longer exposure period, except for hepatic MT induction resulting from waterborne or low dietary Cd exposure. The Cd percentage in the metallothionein-like protein (MTLP) fraction increased over exposure time, and it accounted for more than 57% Cd in the fishes' livers and 80% Cd in their digestive tracts by the end of the exposure period. Overall, although Cd in commercial fish diet did not have significant lethality to T. jarbua, sensitive responses such as hepatic MT induction and subcellular Cd distribution revealed that the Cd-induced storage and detoxification in T. jarbua may increase fish's tolerance to toxic metals.

Enhanced glutathione content allows the in vivo synthesis of fluorescent CdTe nanoparticles by Escherichia coli.

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Juan P Monrás

Full Text Available The vast application of fluorescent semiconductor nanoparticles (NPs or quantum dots (QDs has prompted the development of new, cheap and safer methods that allow generating QDs with improved biocompatibility. In this context, green or biological QDs production represents a still unexplored area. This work reports the intracellular CdTe QDs biosynthesis in bacteria. Escherichia coli overexpressing the gshA gene, involved in glutathione (GSH biosynthesis, was used to produce CdTe QDs. Cells exhibited higher reduced thiols, GSH and Cd/Te contents that allow generating fluorescent intracellular NP-like structures when exposed to CdCl(2 and K(2TeO(3. Fluorescence microscopy revealed that QDs-producing cells accumulate defined structures of various colors, suggesting the production of differently-sized NPs. Purified fluorescent NPs exhibited structural and spectroscopic properties characteristic of CdTe QDs, as size and absorption/emission spectra. Elemental analysis confirmed that biosynthesized QDs were formed by Cd and Te with Cd/Te ratios expected for CdTe QDs. Finally, fluorescent properties of QDs-producing cells, such as color and intensity, were improved by temperature control and the use of reducing buffers.

Safety of nevirapine in HIV-infected pregnant women initiating antiretroviral therapy at higher CD4 counts: a systematic review and meta-analysis.

Science.gov (United States)

Bera, Ebrahim; Mia, Rafiq

2012-10-08

The package insert for nevirapine (NVP) cautions use in HIV-infected women (including pregnant women) with CD4 counts ≥250 cells/µl. However, recent studies showed that the CD4 count of pregnant women receiving antiretroviral therapy (ART) was not predictive of NVP toxicity. To determine whether ART-naive pregnant women initiating NVP-based ART at higher CD4 counts experience greater toxicity compared with pregnant women at lower CD4 counts. We reviewed studies comparing serious adverse NVP-related events among ART-naive pregnant women who commenced therapy at higher v. lower CD4 counts. Relevant studies were extracted from PubMed, SCOPUS and EMBASE, major journals and conference proceedings prior to December 2011. Authors were contacted for additional data. Data were independently extracted and entered into Review Manager. Fourteen studies (2 663 participants) were included for analysis. The odds ratio (OR) for overall NVP toxicity among pregnant women with CD4 <250 cells/µl was 0.61 (95% confidence interval (CI) 0.43 - 0.85). When analysis was restricted to prospective studies only (7 studies, 1 318 participants), the results were consistent for overall NVP toxicity (OR 0.43; 95% CI 0.25 - 0.73) and severe hepatotoxicity (OR 0.45; 95% CI 0.22 - 0.90), but not for severe cutaneous reaction (OR 0.53; 95% CI 0.26 - 1.10). Initiating NVP-based ART during pregnancy at CD4 ≥250 cells/µl increases toxicity risk and should be avoided, necessitating urgent revision of current guidelines supporting this practice.

An optimized multilayer structure of CdS layer for CdTe solar cells application

International Nuclear Information System (INIS)

Han Junfeng; Liao Cheng; Jiang Tao; Spanheimer, C.; Haindl, G.; Fu, Ganhua; Krishnakumar, V.; Zhao Kui; Klein, A.; Jaegermann, W.

2011-01-01

Research highlights: → Two different methods to prepare CdS films for CdTe solar cells. → A new multilayer structure of window layer for the CdTe solar cell. → Thinner CdS window layer for the solar cell than the standard CdS layer. → Higher performance of solar cells based on the new multilayer structure. - Abstract: CdS layers grown by 'dry' (close space sublimation) and 'wet' (chemical bath deposition) methods are deposited and analyzed. CdS prepared with close space sublimation (CSS) has better crystal quality, electrical and optical properties than that prepared with chemical bath deposition (CBD). The performance of CdTe solar cell based on the CSS CdS layer has higher efficiency than that based on CBD CdS layer. However, the CSS CdS suffers from the pinholes. And consequently it is necessary to prepare a 150 nm thin film for CdTe/CdS solar cell. To improve the performance of CdS/CdTe solar cells, a thin multilayer structure of CdS layer (∼80 nm) is applied, which is composed of a bottom layer (CSS CdS) and a top layer (CBD CdS). That bi-layer film can allow more photons to pass through it and significantly improve the short circuit current of the CdS/CdTe solar cells.

Effects of dietary calcium and cadmium on cadmium accumulation, calcium and cadmium uptake from the water, and their interactions in juvenile rainbow trout

Energy Technology Data Exchange (ETDEWEB)

Baldisserotto, B. [Departamento de Fisiologia, Universidade Federal de Santa Maria, 97105.900 Santa Maria, RS (Brazil); Chowdhury, M.J. [Department of Biology, McMaster University, Hamilton, Ont., L8S 4K1 (Canada); Wood, Chris M. [Department of Biology, McMaster University, Hamilton, Ont., L8S 4K1 (Canada)]. E-mail: woodcm@mcmaster.ca

2005-03-25

The objective of this study was to examine the effects of chronically elevated dietary Ca{sup 2+} (as CaCO{sub 3}), alone and in combination with elevated dietary Cd, on survival, growth, and Cd and Ca{sup 2+} accumulation in several internal compartments in juvenile rainbow trout (Oncorhynchus mykiss). In addition, effects on short-term branchial uptake and internal distribution of newly accumulated waterborne Ca{sup 2+} and Cd during acute waterborne Cd exposure (50 {mu}g/L as CdNO{sub 3} for 3 h) were monitored using radiotracers ({sup 45}Ca, {sup 65}Cd). Fish were fed with four diets: 20 mg Ca{sup 2+}/g food (control), 50 mg Ca{sup 2+}/g food, 300 {mu}g Cd/g food, and 50 mg Ca{sup 2+}/g + 300 {mu}g Cd/g food for 30 days. There were no significant effects on growth, mortality, or total body Ca{sup 2+} accumulation. The presence of elevated Ca{sup 2+}, Cd, or Ca{sup 2+} + Cd in the diet all reduced waterborne Ca{sup 2+} uptake in a short-term experiment (3 h), though the inhibitory mechanisms appeared to differ. The effects were marked after 15 days of feeding, but attenuated by 30 days, except when the diet was elevated in both Ca{sup 2+} and Cd. The presence of elevated Ca{sup 2+} in the diet had only modest influence on Cd uptake from the water during acute Cd challenges but greatly depressed Cd uptake from the diet and accumulation in most internal tissues. None of the treatment diets prevented the decreases in waterborne Ca{sup 2+} uptake and new Ca{sup 2+} accumulation in internal tissues caused by acute exposure to waterborne Cd. In conclusion, there are complex interactions between waterborne and dietary effects of Ca{sup 2+} and Cd. Elevated dietary Ca{sup 2+} protects against both dietary and waterborne Cd uptake, whereas both waterborne and dietary Cd elevations cause reduced waterborne Ca{sup 2+} uptake.

Preparation and characterization of pulsed laser deposited CdTe thin films at higher FTO substrate temperature and in Ar + O{sub 2} atmosphere