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[PMID]:29431334
[Au] Autor:Abakumov EV; Suyundukov YT; Pigareva TA; Semenova IN; Semenova RF; Biktimerova G; Rafikova YS; Ilbulova GR
[Ti] Título:[Biological and sanitary evaluation of Sibaisky quarry dumps of the Bashkortostan Republic].
[So] Source:Gig Sanit;95(10):929-34, 2016.
[Is] ISSN:0016-9900
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:Dumps of quarries for the extraction of copper pyrite in Urals region of the Bashkortostan Republic are the problem object, which represents a main technogenic source of environmental pollution. Soils of Sibaisky quarry dumps are characterized by the elevated content of heavy metals relatively to maximum permissible concentrations and regional geochemical background. In sanitary hygienic evaluation of the pollution by studied technosols according to the total pollution index (Zc) it was revealed that according to the content of total forms studied technosols are referred to moderately hazard, while in regards of the same index concerning the content of the mobile forms technosols are referred to the category of hazardous. In this regard, in plant products grown in the area adjacent to the dumps, there was revealed an excess on cadmium. The biological activity of soils is very low, due to the low microbial community development. Soil formation in the dumps is almost not expressed, appearing in the formation of low-thick underdeveloped humus horizon with a little diversity of species and projective cover. Sanitary-hygienic situation in conditions in the quarry dump area is unfavorable, that does not allow newly formed soils to carry out environmental functions effectively
[Mh] Termos MeSH primário: Biota/efeitos dos fármacos
Cobre
Poluição Ambiental
Metais Pesados
Mineração/métodos
Solo
[Mh] Termos MeSH secundário: Bashkiria
Monitoramento Ambiental/métodos
Poluição Ambiental/efeitos adversos
Poluição Ambiental/análise
Seres Humanos
Metais Pesados/efeitos adversos
Metais Pesados/análise
Solo/química
Solo/classificação
Poluentes do Solo/efeitos adversos
Poluentes do Solo/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Metals, Heavy); 0 (Soil); 0 (Soil Pollutants); 789U1901C5 (Copper)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180213
[St] Status:MEDLINE


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[PMID]:29030319
[Au] Autor:Dutta S; Celestine MJ; Khanal S; Huddleston A; Simms C; Arca JF; Mitra A; Heller L; Kraj PJ; Ledizet M; Anderson JF; Neelakanta G; Holder AA; Sultana H
[Ad] Endereço:Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA.
[Ti] Título:Coordination of different ligands to copper(II) and cobalt(III) metal centers enhances Zika virus and dengue virus loads in both arthropod cells and human keratinocytes.
[So] Source:Biochim Biophys Acta;1862(1):40-50, 2018 01.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Trace elements such as copper and cobalt have been associated with virus-host interactions. However, studies to show the effect of conjugation of copper(II) or cobalt(III) metal centers to thiosemicarbazone ligand(s) derived from either food additives or mosquito repellent such as 2-acetylethiazole or citral, respectively, on Zika virus (ZIKV) or dengue virus (serotype 2; DENV2) infections have not been explored. In this study, we show that four compounds comprising of thiosemicarbazone ligand derived from 2-acetylethiazole viz., (E)-N-ethyl-2-[1-(thiazol-2-yl)ethylidene]hydrazinecarbothioamide (acetylethTSC) (compound 1), a copper(II) complex with acetylethTSC as a ligand (compound 2), a thiosemicarbazone ligand-derived from citral (compound 3) and a cobalt(III) complex with a citral-thiosemicarbazone ligand (compound 4) increased DENV2 and ZIKV replication in both mosquito C6/36 cells and human keratinocytes (HaCaT cells). Treatment of both cell lines with compounds 2 or 4 showed increased dengue viral titers at all three tested doses. Enhanced dengue viral plaque formation was also noted at the tested dose of 100µM, suggesting higher production of infectious viral particles. Treatment with the compounds 2 or 4 enhanced ZIKV and DENV2 RNA levels in HeLa cell line and primary cultures of mouse bone marrow derived dendritic cells. Also, pre- or post treatments with conjugated compounds 2 or 4 showed higher loads of ZIKV or DENV2 envelope (E) protein in HaCaT cells. No changes in loads of E-protein were found in ZIKV-infected C6/36 cells, when compounds were treated after infection. In addition, we tested bis(1,10-phenanthroline)copper(II) chloride ([Cu(phen) ]Cl , (compound 5) and tris(1,10-phenanthroline)cobalt(III) chloride ([Co(phen) ]Cl , (compound 6) that also showed enhanced DENV2 loads. Also, we found that copper(II) chloride dehydrate (CuCl ·2H O) or cobalt(II) chloride hexahydrate (CoCl ·6H O) alone had no effects as "free" cations. Taken together, these findings suggest that use of Cu(II) or Co(III) conjugation to organic compounds, in insect repellents and/or food additives could enhance DENV2/ZIKV loads in human cells and perhaps induce pathogenesis in infected individuals or individuals pre-exposed to such conjugated complexes. IMPORTANCE: Mosquito-borne diseases are of great concern to the mankind. Use of chemicals/repellents against mosquito bites and transmission of microbes has been the topic of interest for many years. Here, we show that thiosemicarbazone ligand(s) derived from 2-acetylethiazole or citral or 1,10-phenanthroline upon conjugation with copper(II) or cobalt(III) metal centers enhances dengue virus (serotype 2; DENV2) and/or Zika virus (ZIKV) infections in mosquito, mouse and human cells. Enhanced ZIKV/DENV2 capsid mRNA or envelope protein loads were evident in mosquito cells and human keratinocytes, when treated with compounds before/after infections. Also, treatment with copper(II) or cobalt(III) conjugated compounds increased viral titers and number of plaque formations. These studies suggest that conjugation of compounds in repellents/essential oils/natural products/food additives with copper(II) or cobalt(III) metal centers may not be safe, especially in tropical and subtropical places, where several dengue infection cases and deaths are reported annually or in places with increased ZIKV caused microcephaly.
[Mh] Termos MeSH primário: Cobalto
Complexos de Coordenação
Cobre
Vírus da Dengue/metabolismo
Queratinócitos/virologia
Carga Viral/efeitos dos fármacos
Zika virus/metabolismo
[Mh] Termos MeSH secundário: Animais
Cercopithecus aethiops
Cobalto/química
Cobalto/farmacologia
Complexos de Coordenação/química
Complexos de Coordenação/farmacologia
Cobre/química
Cobre/farmacologia
Culicidae
Células HeLa
Seres Humanos
Queratinócitos/metabolismo
Queratinócitos/patologia
Células Vero
Proteínas do Envelope Viral
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Coordination Complexes); 0 (Viral Envelope Proteins); 3G0H8C9362 (Cobalt); 789U1901C5 (Copper)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171015
[St] Status:MEDLINE


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[PMID]:28942275
[Au] Autor:Yadav P; Kaur R; Kanwar MK; Sharma A; Verma V; Sirhindi G; Bhardwaj R
[Ad] Endereço:Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar 143005, Punjab, India.
[Ti] Título:Castasterone confers copper stress tolerance by regulating antioxidant enzyme responses, antioxidants, and amino acid balance in B. juncea seedlings.
[So] Source:Ecotoxicol Environ Saf;147:725-734, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The aim of the present study was to explore the effect of exogenous application of castasterone (CS) on physiologic and biochemical responses in Brassica juncea seedlings under copper (Cu) stress. Seeds were pre-soaked in different concentrations of CS and grown for 7 days under various levels of Cu. The exposure of B. juncea to higher levels of Cu led to decrease of morphologic parameters, with partial recovery of length and fresh weight in the CS pre-treated seedlings. Metal content was high in both roots and shoots under Cu exposure while the CS pre-treatment reduced the metal uptake. Accumulation of hydrogen peroxide (H O ) and superoxide anion radical (O ) were chosen as stress biomarker and higher levels of H O (88.89%) and O (62.11%) showed the oxidative stress in metal treated B. juncea seedlings, however, CS pre-treatment reduced ROS accumulation in Cu-exposed seedlings. The Cu exposures lead to enhance the plant's enzymatic and non-enzymatic antioxidant system. It was observed that enzymatic activities of ascorbate peroxidase (APOX), dehydroascorbate reductase (DHAR), and glutathione reductase (GR), glutathione perxoidase (GPOX) and gultrathione-s-transferase increased while activity of monodehydroascorbate reductase (MDHAR) decreased under Cu stress. The pre-treatment with CS positively affected the activities of enzymes. RT-PCR analysis showed that mRNA transcript levels were correlated with total enzymatic activity of DHAR, GR, GST and GSH. Increase in the gene expression of DHAR (1.85 folds), GR (3.24 folds), GST-1 (2.00 folds) and GSH-S (3.18 folds) was noticed with CS pre-treatment. Overall, the present study shows that Cu exposure induced severe oxidative stress in B. juncea plants and exogenous application of CS improved antioxidative defense system by modulating the ascorbate-glutathione cycle and amino acid metabolism.
[Mh] Termos MeSH primário: Antioxidantes/metabolismo
Colestanóis/farmacologia
Cobre/toxicidade
Mostardeira/efeitos dos fármacos
Estresse Oxidativo/efeitos dos fármacos
Poluentes do Solo/toxicidade
[Mh] Termos MeSH secundário: Aminoácidos/metabolismo
Cobre/metabolismo
Relação Dose-Resposta a Droga
Expressão Gênica/efeitos dos fármacos
Peróxido de Hidrogênio/metabolismo
Mostardeira/enzimologia
Mostardeira/genética
Poluentes do Solo/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids); 0 (Antioxidants); 0 (Cholestanols); 0 (Soil Pollutants); 789U1901C5 (Copper); 80736-41-0 (castasterone); BBX060AN9V (Hydrogen Peroxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170925
[St] Status:MEDLINE


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[PMID]:28938140
[Au] Autor:Yi X; He J; Guo Y; Han Z; Yang M; Jin J; Gu J; Ou M; Xu X
[Ad] Endereço:College of Chemistry, Fuzhou University, Fuzhou 350108, China. Electronic address: 927208329@qq.com.
[Ti] Título:Encapsulating Fe O into calcium alginate coated chitosan hydrochloride hydrogel beads for removal of Cu (II) and U (VI) from aqueous solutions.
[So] Source:Ecotoxicol Environ Saf;147:699-707, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The aim of this work was to study the removal of Cu (II) and U (VI) ions from aqueous solutions by encapsulating magnetic Fe O nanoparticles into calcium alginate coated chitosan hydrochloride (CCM) hydrogel beads. ATR-FTIR and XRD analysis data indicated that the CCM composites were successfully prepared. SEM images and EDX spectra showed that Cu and UO ions were adhered onto sorbents. Adsorption properties for removal of both copper and uranium ions under various experimental conditions were investigated. Kinetic data and sorption equilibrium isotherms were also conducted in batch process. The sorption kinetic analysis revealed that sorption of Cu (II) and U (VI) followed the pseudo-second-order model well and exhibited 3-stage intraparticle diffusion model during the whole sorption process. Equilibrium data were best described by Langmuir model, and the CCM composite hydrogel beads showed the estimated maximum adsorption capacity 143.276mg/g and 392.692mg/g for Cu (II) and U (VI), respectively. The CCM adsorbent exhibited excellent reusability for five cycles use without significant changes in the adsorption capacity and structural stability. The results demonstrated that CCM can be an effective and promising sorbent for Cu (II) and U (VI) ions in wastewater.
[Mh] Termos MeSH primário: Alginatos/química
Quitosana/química
Cobre/análise
Nanopartículas de Magnetita/química
Compostos de Urânio/análise
Poluentes Químicos da Água/análise
Purificação da Água/métodos
[Mh] Termos MeSH secundário: Adsorção
Ácido Glucurônico/química
Ácidos Hexurônicos/química
Hidrogéis/química
Concentração de Íons de Hidrogênio
Íons
Cinética
Modelos Teóricos
Soluções
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alginates); 0 (Hexuronic Acids); 0 (Hydrogels); 0 (Ions); 0 (Magnetite Nanoparticles); 0 (Solutions); 0 (Uranium Compounds); 0 (Water Pollutants, Chemical); 789U1901C5 (Copper); 8A5D83Q4RW (Glucuronic Acid); 8C3Z4148WZ (alginic acid); 9012-76-4 (Chitosan)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170923
[St] Status:MEDLINE


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[PMID]:28934711
[Au] Autor:Colón-Cruz L; Kristofco L; Crooke-Rosado J; Acevedo A; Torrado A; Brooks BW; Sosa MA; Behra M
[Ad] Endereço:Department of Anatomy and Neurobiology, School of Medicine, Medical Sciences Campus of the University of Puerto Rico (UPR-MSC), San Juan, PR, USA; Puerto Rico Center for Environmental Neuroscience, Institute of Neurobiology, Medical Sciences Campus of the University of Puerto Rico, San Juan, PR, USA
[Ti] Título:Alterations of larval photo-dependent swimming responses (PDR): New endpoints for rapid and diagnostic screening of aquatic contamination.
[So] Source:Ecotoxicol Environ Saf;147:670-680, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Detection and toxicity assessment of waterborne contaminants are crucial for protecting human health and the environment. Development of easy-to-implement, rapid and cost-effective tools to measure anthropogenic effects on watersheds are critical for responsible management, particularly in times of increasing development and urbanization. Traditionally, environmental toxicology has focused on limited endpoints, such as lethality and fertility, which are directly affecting population levels. However, more sensitive readings are needed to assess sub-lethal effects. Monitoring of contaminant-induced behavior alterations was proposed before, but is difficult to implement in the wild and performing it in aquatic laboratory models seem more suited. For this purpose, we adapted a photo-dependent swimming response (PDR) that was previously described in zebrafish larva. We first asked if PDR was present in other aquatic animals. We measured PDR in larvae from two freshwater prawn species (Macrobrachium rosenbergii, MR, and Macrobrachium carcinus, MC) and from another fish the fathead minnow (FHM, Pimephales promelas). In all, we found a strong and reproducible species-specific PDR, which is arguing that this behavior is important, therefore an environmental relevant endpoint. Next, we measured PDR in fish larvae after acute exposure to copper, a common waterborne contaminant. FHM larvae were hyperactive at all tested concentrations in contrast to ZF larvae, which exhibited a concentration-dependent hyperactivity. In addition to this well-accepted anxiety-like behavior, we examined two more: photo-stimulated startle response (PSSR) and center avoidance (CA). Both were significantly increased. Therefore, PDR measures after acute exposure to this waterborne contaminant provided as sensitive readout for its detection and toxicity assessment. This approach represents an opportunity to diagnostically examine any substance, even when present in complex mixtures like ambient surface waters. Mechanistic studies of toxicity using the extensive molecular tool kit of ZF could be a direct extension of such approaches.
[Mh] Termos MeSH primário: Cobre/toxicidade
Monitoramento Ambiental/métodos
Larva/efeitos dos fármacos
Luz
Natação
Poluentes Químicos da Água/toxicidade
[Mh] Termos MeSH secundário: Animais
Comportamento Animal/efeitos dos fármacos
Comportamento Animal/efeitos da radiação
Peixes/fisiologia
Água Doce/química
Seres Humanos
Larva/fisiologia
Larva/efeitos da radiação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Water Pollutants, Chemical); 789U1901C5 (Copper)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170922
[St] Status:MEDLINE


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[PMID]:28865349
[Au] Autor:Li X; Zhang D; Sheng F; Qing H
[Ad] Endereço:Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Conservancy, Chengdu 610041, China.
[Ti] Título:Adsorption characteristics of Copper (â…¡), Zinc (â…¡) and Mercury (â…¡) by four kinds of immobilized fungi residues.
[So] Source:Ecotoxicol Environ Saf;147:357-366, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:This study investigated the adsorption characteristics of Copper (â…¡), Zinc (â…¡) and Mercury (â…¡) by immobilized Flammulina velutipes, Auricularia polytricha, Pleurotus eryngii and Pleurotus ostreatus residues. Lagergren model, elovich and intraparticle diffusion model were used to present the adsorption kinetics, and it was proved that Langmuir isotherm model and pseudo-second order kinetics are the best suitable model with high correlation coefficient to characterize the adsorption process of Copper (â…¡), Zinc (â…¡) and Mercury (â…¡). The results showed that adsorption process finished in 120min at pH 6.0. The adsorption rate of Cu , Zn and Hg were reached to 53.8-84.1% of total in the initial 60min, and finished in 120min. Ion exchange and complexation of F. velutipes were the main mechanisms for adsorption of metal ions by characterizations of Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). In addition the functional group of cell walls such as hydroxyl, amide, carbonyl, phosphoric played a critical role in ions adsorption of edible mushroom residues. Cu , Zn and Hg in wastewater could be efficiently removed by F. velutipes residue with removal ratio of 73.11%, 66.67% and 69.35%, respectively.
[Mh] Termos MeSH primário: Agaricales/química
Cobre/análise
Mercúrio/análise
Modelos Teóricos
Poluentes Químicos da Água/análise
Zinco/análise
[Mh] Termos MeSH secundário: Adsorção
Cobre/química
Difusão
Concentração de Íons de Hidrogênio
Íons
Cinética
Mercúrio/química
Resíduos Sólidos/análise
Termodinâmica
Águas Residuais/química
Poluentes Químicos da Água/química
Purificação da Água/métodos
Zinco/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ions); 0 (Solid Waste); 0 (Waste Water); 0 (Water Pollutants, Chemical); 789U1901C5 (Copper); FXS1BY2PGL (Mercury); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170903
[St] Status:MEDLINE


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[PMID]:28858705
[Au] Autor:Biandolino F; Parlapiano I; Faraponova O; Prato E
[Ad] Endereço:CNR-IAMC, Institute for Coastal Marine Environment, Taranto, Italy. Electronic address: francesca.biandolino@iamc.cnr.it.
[Ti] Título:Effects of short- and long-term exposures to copper on lethal and reproductive endpoints of the harpacticoid copepod Tigriopus fulvus.
[So] Source:Ecotoxicol Environ Saf;147:327-333, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The long-term exposure provides a realistic measurement of the effects of toxicants on aquatic organisms. The harpacticoid copepod Tigriopus fulvus has a wide geographical distribution and is considered as an ideal model organism for ecotoxicological studies for its good sensitivity to different toxicants. In this study, acute, sub-chronic and chronic toxicity tests based on lethal and reproductive responses of Tigriopus fulvus to copper were performed. The number of moults during larval development was chosen as an endpoint for sub-chronic test. Sex ratio, inhibitory effect on larval development, hatching time, fecundity, brood number, nauplii/brood, total newborn production, etc, were calculated in the chronic test (28d). Lethal effect of copper to nauplii showed the LC50-48h of 310 ± 72µgCu/L (mean ± sd). It was observed a significant inhibition of larval development at sublethal copper concentrations, after 4 and 7 d. After 4d, the EC50 value obtained for the endpoint in "moult naupliar reduction" was of 55.8 ± 2.5µgCu/L (mean ± sd). The EC50 for the inhibition of naupliar development into copepodite stage, was of 21.7 ± 4.4µgCu/L (mean ± sd), after 7 days. Among the different traits tested, copper did not affect sex ratio and growth, while fecundity and total nauplii production were the most sensitive endpoints. The reproductive endpoints offer the advantage of being detectable at very low pollutant concentrations.
[Mh] Termos MeSH primário: Copépodes/efeitos dos fármacos
Cobre/toxicidade
Monitoramento Ambiental/métodos
Poluentes Químicos da Água/toxicidade
[Mh] Termos MeSH secundário: Animais
Copépodes/crescimento & desenvolvimento
Determinação de Ponto Final
Fertilidade/efeitos dos fármacos
Dose Letal Mediana
Reprodução/efeitos dos fármacos
Razão de Masculinidade
Fatores de Tempo
Testes de Toxicidade Aguda
Testes de Toxicidade Crônica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Water Pollutants, Chemical); 789U1901C5 (Copper)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170901
[St] Status:MEDLINE


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[PMID]:28466911
[Au] Autor:Scheller JS; Irvine GW; Wong DL; Hartwig A; Stillman MJ
[Ad] Endereço:Department of Chemistry, The University of Western Ontario, London, Ontario, N6A 5B7, Canada. martin.stillman@uwo.ca.
[Ti] Título:Stepwise copper(i) binding to metallothionein: a mixed cooperative and non-cooperative mechanism for all 20 copper ions.
[So] Source:Metallomics;9(5):447-462, 2017 May 24.
[Is] ISSN:1756-591X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Copper is a ubiquitous trace metal of vital importance in that it serves as a cofactor in many metalloenzymes. Excess copper becomes harmful if not sequestered appropriately in the cell. As a metal ion chaperone, metallothionein (MT) has been proposed as a key player in zinc and copper homeostasis within the cell. The underlying mechanisms by which MT sequesters and transfers copper ions, and subsequently achieves its proposed biological function remain unknown. Using a combination of electrospray ionization mass spectrometry (ESI-MS), circular dichroism (CD), and emission spectroscopy, we report that the Cu(i) to human apo-MT1a binding mechanism is highly pH-dependent. The 20 relative K -values for the binding of 1 to 20 Cu(i) to the 20 cysteines of MT were obtained from computational simulation of the experimental mass spectral results. These data identified the pH-dependent formation of three sequential but completely different Cu-S clusters, as a function of Cu(i) loading. These data provide the first overall sequence for Cu(i) binding in terms of domain specificity and transient binding site structures. Under cooperative binding at pH 7.4, a series of four clusters form: Cu S , followed by Cu S (ß), then a second Cu S (α), and finally Cu S (α) (x = up to 11). Upon further addition of Cu(i), a mixture of species is formed in a non-cooperative mechanism, saturating the 20 cysteines of MT1a. Using benzoquinone, a cysteine modifier, we were able to confirm that Cu S formed solely in the N-terminal ß-domain, as well as confirming the existence of the presumed Cu S cluster in the α-domain. Based on the results of ESI-MS and computational simulation we were able to identify Cu:MT speciation that resulted in specific emission and CD spectral properties.
[Mh] Termos MeSH primário: Cobre/metabolismo
Metalotioneína/metabolismo
[Mh] Termos MeSH secundário: Sítios de Ligação
Dicroísmo Circular
Cobre/química
Seres Humanos
Concentração de Íons de Hidrogênio
Metalotioneína/química
Modelos Moleculares
Ligação Proteica
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
Espectrometria de Massas por Ionização por Electrospray
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (MT1A protein, human); 0 (Recombinant Proteins); 789U1901C5 (Copper); 9038-94-2 (Metallothionein)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1039/c7mt00041c


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[PMID]:28968938
[Au] Autor:Rotini A; Gallo A; Parlapiano I; Berducci MT; Boni R; Tosti E; Prato E; Maggi C; Cicero AM; Migliore L; Manfra L
[Ad] Endereço:Department of Biology, University Tor Vergata, Rome, Italy; Institute for Environmental Protection and Research (ISPRA), Rome, Italy.
[Ti] Título:Insights into the CuO nanoparticle ecotoxicity with suitable marine model species.
[So] Source:Ecotoxicol Environ Saf;147:852-860, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Metal oxide nanoparticles, among them copper oxide nanoparticles (CuO NPs), are widely used in different applications (e.g. batteries, gas sensors, superconductors, plastics and metallic coatings), increasing their potential release in the environment. In aquatic matrix, the behavior of CuO NPs may strongly change, depending on their surface charge and some physical-chemical characteristics of the medium (e.g. ionic strength, salinity, pH and natural organic matter content). Ecotoxicity of CuO NPs to aquatic organisms was mainly studied on freshwater species, few tests being performed on marine biota. The aim of this study was to assess the toxicity of CuO NPs on suitable indicator species, belonging to the ecologically relevant level of consumers. The selected bioassays use reference protocols to identify Effect/Lethal Concentrations (E(L)C), by assessing lethal and sub-lethal endpoints. Mortality tests were performed on rotifer (Brachionus plicatilis), shrimp (Artemia franciscana) and copepod (Tigriopus fulvus). While moult release failure and fertilization rate were studied, as sub-lethal endpoints, on T. fulvus and sea urchin (Paracentrotus lividus), respectively. The size distribution and sedimentation rates of CuO NPs, together with the copper dissolution, were also analyzed in the exposure media. The CuO NP ecotoxicity assessment showed a concentration-dependent response for all species, indicating similar mortality for B. plicatilis (48hLC = 16.94 ± 2.68mg/l) and T. fulvus (96hLC = 12.35 ± 0.48mg/l), followed by A. franciscana (48hLC = 64.55 ± 3.54mg/l). Comparable EC values were also obtained for the sub-lethal endpoints in P. lividus (EC = 2.28 ± 0.06mg/l) and T. fulvus (EC = 2.38 ± 0.20mg/l). Copper salts showed higher toxicity than CuO NPs for all species, with common sensitivity trend as follows: P. lividus ≥ T. fulvus (sublethal endpoint) ≥ B. plicatilis >T. fulvus (lethal endpoint) >A. franciscana. CuO NP micrometric aggregates and high sedimentation rates were observed in the exposure media, with different particle size distributions depending on the medium. The copper dissolution was about 0.16% of the initial concentration, comparable to literature values. The integrated ecotoxicological-physicochemical approach was used to better describe CuO NP toxicity and behavior. In particular, the successful application of ecotoxicological reference protocols allowed to produce reliable L(E)C data useful to identify thresholds and assess potential environmental hazard due to NPs.
[Mh] Termos MeSH primário: Organismos Aquáticos/efeitos dos fármacos
Cobre/toxicidade
Nanopartículas Metálicas/toxicidade
Poluentes Químicos da Água/toxicidade
[Mh] Termos MeSH secundário: Animais
Ecotoxicologia
Água Doce
Modelos Animais
Tamanho da Partícula
Salinidade
Especificidade da Espécie
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Water Pollutants, Chemical); 789U1901C5 (Copper); V1XJQ704R4 (cupric oxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171004
[St] Status:MEDLINE


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[PMID]:28822946
[Au] Autor:Xu ZR; Cai SW; Huang WX; Liu RX; Xiong ZT
[Ad] Endereço:School of Resource and Environmental Sciences, Wuhan University, Wuhan, Hubei, People's Republic of China.
[Ti] Título:Differential expression of vacuolar and defective cell wall invertase genes in roots and seeds of metalliferous and non-metalliferous populations of Rumex dentatus under copper stress.
[So] Source:Ecotoxicol Environ Saf;147:17-25, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Acid invertase activities in roots and young seeds of a metalliferous population (MP) of Rumex dentatus were previously observed to be significantly higher than those of a non-metalliferous population (NMP) under Cu stress. To date, no acid invertase gene has been cloned from R. dentatus. Here, we isolated four full-length cDNAs from the two populations of R. dentatus, presumably encoding cell wall (RdnCIN1 and RdmCIN1 from the NMP and MP, respectively) and vacuolar invertases (RdnVIN1 and RdmVIN1 from the NMP and MP, respectively). Unexpectedly, RdnCIN1 and RdmCIN1 most likely encode special defective invertases with highly attenuated sucrose-hydrolyzing capacity. The transcript levels of RdmCIN1 were significantly higher than those of RdnCIN1 in roots and young seeds under Cu stress, whereas under control conditions, the former was initially lower than the latter. Unexpected high correlations were observed between the transcript levels of RdnCIN1 and RdmCIN1 and the activity of cell wall invertase, even though RdnCIN1 and RdmCIN1 do not encode catalytically active invertases. Similarly, the transcript levels of RdmVIN1 in roots and young seeds were increased under Cu stress, whereas those of RdnVIN1 were decreased. The high correlations between the transcript levels of RdnVIN1 and RdmVIN1 and the activity of vacuolar invertase indicate that RdnVIN1 and RdmVIN1 might control distinct vacuolar invertase activities in the two populations. Moreover, a possible indirect role for acid invertases in Cu tolerance, mediated by generating a range of sugars used as nutrients and signaling molecules, is discussed.
[Mh] Termos MeSH primário: Parede Celular/efeitos dos fármacos
Cobre/toxicidade
Rumex/efeitos dos fármacos
Poluentes do Solo/toxicidade
Vacúolos/efeitos dos fármacos
beta-Frutofuranosidase/genética
[Mh] Termos MeSH secundário: Parede Celular/enzimologia
Parede Celular/genética
Cobre/metabolismo
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
Genes de Plantas
Raízes de Plantas/efeitos dos fármacos
Raízes de Plantas/enzimologia
Raízes de Plantas/metabolismo
Rumex/genética
Rumex/metabolismo
Sementes/efeitos dos fármacos
Sementes/enzimologia
Sementes/genética
Poluentes do Solo/metabolismo
Vacúolos/enzimologia
Vacúolos/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Soil Pollutants); 789U1901C5 (Copper); EC 3.2.1.26 (beta-Fructofuranosidase)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170821
[St] Status:MEDLINE



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