Isolating metal-tolerant bacteria capable of removing copper, chromium, and arsenic from treated wood

Treesearch

Carol A. Clausen

2000-01-01

Bioremediation of chromated copper arsenate-treated waste wood with one or more metal-tolerant bacteria is a potential method of naturally releasing metals from treated wood fibre. Sampling eight environments with elevated levels of copper, chromium, and arsenic resulted in the isolation of 28 bacteria with the capability of releasing one or more of the components from...

Metal Dyshomeostasis and Inflammation in Alzheimer's and Parkinson's Diseases: Possible Impact of Environmental Exposures

PubMed Central

Myhre, Oddvar; Utkilen, Hans; Duale, Nur; Brunborg, Gunnar; Hofer, Tim

2013-01-01

A dysregulated metal homeostasis is associated with both Alzheimer's (AD) and Parkinson's (PD) diseases; AD patients have decreased cortex and elevated serum copper levels along with extracellular amyloid-beta plaques containing copper, iron, and zinc. For AD, a putative hepcidin-mediated lowering of cortex copper mechanism is suggested. An age-related mild chronic inflammation and/or elevated intracellular iron can trigger hepcidin production followed by its binding to ferroportin which is the only neuronal iron exporter, thereby subjecting it to lysosomal degradation. Subsequently raised neuronal iron levels can induce translation of the ferroportin assisting and copper binding amyloid precursor protein (APP); constitutive APP transmembrane passage lowers the copper pool which is important for many enzymes. Using in silico gene expression analyses, we here show significantly decreased expression of copper-dependent enzymes in AD brain and metallothioneins were upregulated in both diseases. Although few AD exposure risk factors are known, AD-related tauopathies can result from cyanobacterial microcystin and β-methylamino-L-alanine (BMAA) intake. Several environmental exposures may represent risk factors for PD; for this disease neurodegeneration is likely to involve mitochondrial dysfunction, microglial activation, and neuroinflammation. Administration of metal chelators and anti-inflammatory agents could affect disease outcomes. PMID:23710288

Molecular Mediators Governing Iron-Copper Interactions

PubMed Central

Gulec, Sukru; Collins, James F.

2015-01-01

Given their similar physiochemical properties, it is a logical postulate that iron and copper metabolism are intertwined. Indeed, iron-copper interactions were first documented over a century ago, but the homeostatic effects of one on the other has not been elucidated at a molecular level to date. Recent experimental work has, however, begun to provide mechanistic insight into how copper influences iron metabolism. During iron deficiency, elevated copper levels are observed in the intestinal mucosa, liver, and blood. Copper accumulation and/or redistribution within enterocytes may influence iron transport, and high hepatic copper may enhance biosynthesis of a circulating ferroxidase, which potentiates iron release from stores. Moreover, emerging evidence has documented direct effects of copper on the expression and activity of the iron-regulatory hormone hepcidin. This review summarizes current experimental work in this field, with a focus on molecular aspects of iron-copper interplay and how these interactions relate to various disease states. PMID:24995690

Selection of Fecal Enterococci Exhibiting tcrB-Mediated Copper Resistance in Pigs Fed Diets Supplemented with Copper † ▿

PubMed Central

Amachawadi, R. G.; Shelton, N. W.; Shi, X.; Vinasco, J.; Dritz, S. S.; Tokach, M. D.; Nelssen, J. L.; Scott, H. M.; Nagaraja, T. G.

2011-01-01

Copper, as copper sulfate, is increasingly used as an alternative to in-feed antibiotics for growth promotion in weaned piglets. Acquired copper resistance, conferred by a plasmid-borne, transferable copper resistance (tcrB) gene, has been reported in Enterococcus faecium and E. faecalis. A longitudinal field study was undertaken to determine the relationship between copper supplementation and the prevalence of tcrB-positive enterococci in piglets. The study was done with weaned piglets, housed in 10 pens with 6 piglets per pen, fed diets supplemented with a normal (16.5 ppm; control) or an elevated (125 ppm) level of copper. Fecal samples were randomly collected from three piglets per pen on days 0, 14, 28, and 42 and plated on M-Enterococcus agar, and three enterococcal isolates were obtained from each sample. The overall prevalence of tcrB-positive enterococci was 21.1% (38/180) in piglets fed elevated copper and 2.8% (5/180) in the control. Among the 43 tcrB-positive isolates, 35 were E. faecium and 8 were E. faecalis. The mean MICs of copper for tcrB-negative and tcrB-positive enterococci were 6.2 and 22.2 mM, respectively. The restriction digestion of the genomic DNA of E. faecium or E. faecalis with S1 nuclease yielded a band of ∼194-kbp size to which both tcrB and the erm(B) gene probes hybridized. A conjugation assay demonstrated cotransfer of tcrB and erm(B) genes between E. faecium and E. faecalis strains. The higher prevalence of tcrB-positive enterococci in piglets fed elevated copper compared to that in piglets fed normal copper suggests that supplementation of copper in swine diets selected for resistance. PMID:21705534

Diabetic cardiomyopathy is associated with defective myocellular copper regulation and both defects are rectified by divalent copper chelation

PubMed Central

2014-01-01

Background Heart disease is the leading cause of death in diabetic patients, and defective copper metabolism may play important roles in the pathogenesis of diabetic cardiomyopathy (DCM). The present study sought to determine how myocardial copper status and key copper-proteins might become impaired by diabetes, and how they respond to treatment with the Cu (II)-selective chelator triethylenetetramine (TETA) in DCM. Methods Experiments were performed in Wistar rats with streptozotocin (STZ)-induced diabetes with or without TETA treatment. Cardiac function was analyzed in isolated-perfused working hearts, and myocardial total copper content measured by particle-induced x-ray emission spectroscopy (PIXE) coupled with Rutherford backscattering spectrometry (RBS). Quantitative expression (mRNA and protein) and/or activity of key proteins that mediate LV-tissue-copper binding and transport, were analyzed by combined RT-qPCR, western blotting, immunofluorescence microscopy, and enzyme activity assays. Statistical analysis was performed using Student’s t-tests or ANOVA and p-values of < 0.05 have been considered significant. Results Left-ventricular (LV) copper levels and function were severely depressed in rats following 16-weeks’ diabetes, but both were unexpectedly normalized 8-weeks after treatment with TETA was instituted. Localized myocardial copper deficiency was accompanied by decreased expression and increased polymerization of the copper-responsive transition-metal-binding metallothionein proteins (MT1/MT2), consistent with impaired anti-oxidant defences and elevated susceptibility to pro-oxidant stress. Levels of the high-affinity copper transporter-1 (CTR1) were depressed in diabetes, consistent with impaired membrane copper uptake, and were not modified by TETA which, contrastingly, renormalized myocardial copper and increased levels and cell-membrane localization of the low-affinity copper transporter-2 (CTR2). Diabetes also lowered indexes of intracellular (IC) copper delivery via the copper chaperone for superoxide dismutase (CCS) to its target cuproenzyme, superoxide dismutase-1 (SOD1): this pathway was rectified by TETA treatment, which normalized SOD1 activity with consequent bolstering of anti-oxidant defenses. Furthermore, diabetes depressed levels of additional intracellular copper-transporting proteins, including antioxidant-protein-1 (ATOX1) and copper-transporting-ATPase-2 (ATP7B), whereas TETA elevated copper-transporting-ATPase-1 (ATP7A). Conclusions Myocardial copper deficiency and defective cellular copper transport/trafficking are revealed as key molecular defects underlying LV impairment in diabetes, and TETA-mediated restoration of copper regulation provides a potential new class of therapeutic molecules for DCM. PMID:24927960

Physiological responses of coastal phytoplankton (Visakhapatnam, SW Bay of Bengal, India) to experimental copper addition.

PubMed

Biswas, Haimanti; Bandyopadhyay, Debasmita

2017-10-01

Trace amount of copper (Cu) is essential for many physiological processes; however, it can be potentially toxic at elevated levels. The impact of variable Cu concentrations on a coastal phytoplankton community was investigated along a coastal transect in SW Bay of Bengal. A small increase in Cu supply enhanced the concentrations of particulate organic carbon, particulate organic nitrogen, biogenic silica, total pigment, phytoplankton cell and total bacterial count. At elevated Cu levels all these parameters were adversely affected. δ 13 C POM and δ 15 N POC reflected a visible signature of both beneficial and toxic impacts of Cu supply. Skeletonema costatum, the dominant diatom species, showed higher tolerance to increasing Cu levels relative to Chaetoceros sp. Cyanobacteria showed greater sensitivity to copper than diatoms. The magnitude of Cu toxicity on the phytoplankton communities was inversely related to the distance from the coast. Co-enrichment of iron alleviated Cu toxicity to phytoplankton. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evolution of a Heavy Metal Homeostasis/Resistance Island Reflects Increasing Copper Stress in Enterobacteria

PubMed Central

Staehlin, Benjamin M.; Gibbons, John G.; Rokas, Antonis; O’Halloran, Thomas V.; Slot, Jason C.

2016-01-01

Copper homeostasis in bacteria is challenged by periodic elevation of copper levels in the environment, arising from both natural sources and human inputs. Several mechanisms have evolved to efflux copper from bacterial cells, including the cus (copper sensing copper efflux system), and pco (plasmid-borne copper resistance system) systems. The genes belonging to these two systems can be physically clustered in a Copper Homeostasis and Silver Resistance Island (CHASRI) on both plasmids and chromosomes in Enterobacteria. Increasing use of copper in agricultural and industrial applications raises questions about the role of human activity in the evolution of novel copper resistance mechanisms. Here we present evidence that CHASRI emerged and diversified in response to copper deposition across aerobic and anaerobic environments. An analysis of diversification rates and a molecular clock model suggest that CHASRI experienced repeated episodes of elevated diversification that could correspond to peaks in human copper production. Phylogenetic analyses suggest that CHASRI originated in a relative of Enterobacter cloacae as the ultimate product of sequential assembly of several pre-existing two-gene modules. Once assembled, CHASRI dispersed via horizontal gene transfer within Enterobacteriaceae and also to certain members of Shewanellaceae, where the original pco module was replaced by a divergent pco homolog. Analyses of copper stress mitigation suggest that CHASRI confers increased resistance aerobically, anaerobically, and during shifts between aerobic and anaerobic environments, which could explain its persistence in facultative anaerobes and emergent enteric pathogens. PMID:26893455

Turning tumor-promoting copper into an anti-cancer weapon via high-throughput chemistry.

PubMed

Wang, F; Jiao, P; Qi, M; Frezza, M; Dou, Q P; Yan, B

2010-01-01

Copper is an essential element for multiple biological processes. Its concentration is elevated to a very high level in cancer tissues for promoting cancer development through processes such as angiogenesis. Organic chelators of copper can passively reduce cellular copper and serve the role as inhibitors of angiogenesis. However, they can also actively attack cellular targets such as proteasome, which plays a critical role in cancer development and survival. The discovery of such molecules initially relied on a step by step synthesis followed by biological assays. Today high-throughput chemistry and high-throughput screening have significantly expedited the copper-binding molecules discovery to turn "cancer-promoting" copper into anti-cancer agents.

Urinary Copper Elevation in a Mouse Model of Wilson's Disease Is a Regulated Process to Specifically Decrease the Hepatic Copper Load

PubMed Central

Gray, Lawrence W.; Peng, Fangyu; Molloy, Shannon A.; Pendyala, Venkata S.; Muchenditsi, Abigael; Muzik, Otto; Lee, Jaekwon; Kaplan, Jack H.; Lutsenko, Svetlana

2012-01-01

Body copper homeostasis is regulated by the liver, which removes excess copper via bile. In Wilson's disease (WD), this function is disrupted due to inactivation of the copper transporter ATP7B resulting in hepatic copper overload. High urinary copper is a diagnostic feature of WD linked to liver malfunction; the mechanism behind urinary copper elevation is not fully understood. Using Positron Emission Tomography-Computed Tomography (PET-CT) imaging of live Atp7b−/− mice at different stages of disease, a longitudinal metal analysis, and characterization of copper-binding molecules, we show that urinary copper elevation is a specific regulatory process mediated by distinct molecules. PET-CT and atomic absorption spectroscopy directly demonstrate an age-dependent decrease in the capacity of Atp7b−/− livers to accumulate copper, concomitant with an increase in urinary copper. This reciprocal relationship is specific for copper, indicating that cell necrosis is not the primary cause for the initial phase of metal elevation in the urine. Instead, the urinary copper increase is associated with the down-regulation of the copper-transporter Ctr1 in the liver and appearance of a 2 kDa Small Copper Carrier, SCC, in the urine. SCC is also elevated in the urine of the liver-specific Ctr1 −/− knockouts, which have normal ATP7B function, suggesting that SCC is a normal metabolite carrying copper in the serum. In agreement with this hypothesis, partially purified SCC-Cu competes with free copper for uptake by Ctr1. Thus, hepatic down-regulation of Ctr1 allows switching to an SCC-mediated removal of copper via kidney when liver function is impaired. These results demonstrate that the body regulates copper export through more than one mechanism; better understanding of urinary copper excretion may contribute to an improved diagnosis and monitoring of WD. PMID:22802922

Refrigeration Plant, North Elevation, Second Floor Plan, East Elevation, Ground ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Refrigeration Plant, North Elevation, Second Floor Plan, East Elevation, Ground Floor Plan, Section A-A - Kennecott Copper Corporation, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

Genomic and Transcriptomic Analyses to Identify Pathways Involved in Nanoparticle Generation in the Ubiquitous Marine Bacterium Alteromonas macleodii Under Elevated Copper Conditions

NASA Astrophysics Data System (ADS)

Cusick, K. D.; Dale, J.; Little, B.; Cockrell, A.; Biffinger, J.

2016-02-01

Alteromonas macleodii is a ubiquitous marine bacterium that clusters by molecular analyses into two ecotypes: surface and deep-water. Our group isolated a marine bacterium from copper coupons that generates nanoparticles (NPs) at elevated copper concentrations. Sequencing of the 16S rRNA gene identified it as an A. macleodii strain. In phylogenetic analyses based on the gyrB gene, it clustered with other surface isolates; however, it formed a unique cluster separate from that of other surface isolates based on rpoB gene sequences. Copper is commonly employed as an antifouling agent on the hulls of ships, and so copper tolerance and NP generation is under investigation in this strain. The overall goals of this study were: (1) to determine if copper tolerance is the result of changes at the genetic or transcriptional level and (2) to identify the genes involved in NP formation. Sub-cultures were established from the initial isolate in which copper concentrations were increased in .25 mM increments through multiple generations. These sub-cultures were assayed for NP formation in seawater medium supplemented with 3-4 mM copper. Scanning electron microscopy revealed large aggregates of NPs on the exterior surface of all sub-cultures. Additionally, a portion of the cells in all sub-cultures displayed an elongated morphology in comparison to the wild-type. No NPs were observed in wild-type controls grown without the addition of increased copper. Metagenomic sequencing of natural populations of A. macleodii revealed extreme divergence in several large genomic regions whose content includes genes coding for exopolysaccharide production and metal resistance. High-throughput sequencing is being used to determine whether copper tolerance and NP generation is the result of genetic or transcriptional changes. These results will be extended to natural communities to gain insights into the role of bacterial NPs during conditions of elevated metal concentrations in coastal systems.

Results of a preimpoundment water-quality study of Swatara Creek, Pennsylvania

USGS Publications Warehouse

Fishel, David K.; Richardson, J.E.

1986-01-01

The impoundment will act as a sediment trap and thus reduce the concentrations of total phosphorus, iron, aluminum, lead, copper, and zinc immediately downstream from the impoundment. Large storm discharges and releases from the hypolimnion of the reservoir to attain the winter-pool level may contain low oxygen concentrations and elevated concentrations of iron, aluminum, lead, copper, and zinc. Unless conservation releases from the multi-level release gates are carefully controlled, low dissolved-oxygen levels and high metal concentrations may degrade the downstream water quality and be detrimental to the aquatic community.

Copper Ion from Cu2O Crystal Induces AMPK-Mediated Autophagy via Superoxide in Endothelial Cells

PubMed Central

Seo, Youngsik; Cho, Young-Sik; Huh, Young-Duk; Park, Heonyong

2016-01-01

Copper is an essential element required for a variety of functions exerted by cuproproteins. An alteration of the copper level is associated with multiple pathological conditions including chronic ischemia, atherosclerosis and cancers. Therefore, copper homeostasis, maintained by a combination of two copper ions (Cu+ and Cu2+), is critical for health. However, less is known about which of the two copper ions is more toxic or functional in endothelial cells. Cubic-shaped Cu2O and CuO crystals were prepared to test the role of the two different ions, Cu+ and Cu2+, respectively. The Cu2O crystal was found to have an effect on cell death in endothelial cells whereas CuO had no effect. The Cu2O crystals appeared to induce p62 degradation, LC3 processing and an elevation of LC3 puncta, important processes for autophagy, but had no effect on apoptosis and necrosis. Cu2O crystals promote endothelial cell death via autophagy, elevate the level of reactive oxygen species such as superoxide and nitric oxide, and subsequently activate AMP-activated protein kinase (AMPK) through superoxide rather than nitric oxide. Consistently, the AMPK inhibitor Compound C was found to inhibit Cu2O-induced AMPK activation, p62 degradation, and LC3 processing. This study provides insight on the pathophysiologic function of Cu+ ions in the vascular system, where Cu+ induces autophagy while Cu2+ has no detected effect. PMID:26743904

Impact on sediments and water by release of copper from chalcopyrite bearing rock due to acidic mine drainage

NASA Astrophysics Data System (ADS)

Shukla, Anoop Kant; Pradhan, Manoj; Tiwari, Onkar Nath

2018-04-01

Mining activity causes transition of rock-mass from its original position in earth into open environment. The action of environmental elements such air, water, microorganisms leads to oxidation of minerals which constitute the rock. The oxidation of sulphide minerals in presence of moisture releases acidic mine discharge (AMD). The acidic nature of AMD causes leaching of metals from rock minerals. Dissolution of other minerals may occur upon reaction with AMD. Chalcopyrite (CuFeS2) undergoes oxidation in acidic condition releasing copper among other products. This study reveals contamination of copper in sediment samples and seepage water from the tailing dam of a large copper project in located in central India. Elevation was studied using GIS to ascertain to the topographic elevation of tailing dam area. It was located at relatively high altitude causing seepage to flow away from tailing dam. The seepage water from tailing dam was found to be acidic with mean pH value of 4.0 and elevated copper content. Similarly, sediments from seepage water flow displayed elevated copper concentration. The copper concentration in seepage water was found with a mean value of 10.73 mg/l. The sediments from seepage water flow also displayed elevated copper concentration with mean value of 26.92 g/kg. This indicates impact on sediments by release of copper due to acidic mine drainage.

Lingual dyskinesia and tics: a novel presentation of copper-metabolism disorder.

PubMed

Goez, Helly R; Jacob, Francois D; Yager, Jerome Y

2011-02-01

Copper is a trace element that is required for cellular respiration, neurotransmitter biosynthesis, pigment formation, antioxidant defense, peptide amidation, and formation of connective tissue. Abnormalities of copper metabolism have been linked with neurologic disorders that affect movement, such as Wilson disease and Menkes disease; however, the diagnosis of non-Wilson, non-Menkes-type copper-metabolism disorders has been more elusive, especially in cases with atypical characteristics. We present here the case of an adolescent with a novel presentation of copper-metabolism disorder who exhibited acute severe hemilingual dyskinesia and prominent tics, with ballismus of the upper limbs, but had normal brain and spinal MRI results and did not show any signs of dysarthria or dysphagia. His serum copper and ceruloplasmin levels were low, but his urinary copper level was elevated after penicillamine challenge. We conclude that copper-metabolism disorders should be included in the differential diagnosis for movement disorders, even in cases with highly unusual presentations, because many of them are treatable. Moreover, a connection between copper-metabolism disorders and tics is presented, to our knowledge, for the first time in humans; further investigation is needed to better establish this connection and understand its underlying pathophysiology.

Role of Copper and Homocysteine in Pressure Overload Heart Failure

PubMed Central

Hughes, William M.; Rodriguez, Walter E.; Rosenberger, Dorothea; Chen, Jing; Sen, Utpal; Tyagi, Neetu; Moshal, Karni S.; Vacek, Thomas; Kang, Y. James

2009-01-01

Elevated levels of homocysteine (Hcy) (known as hyperhomocysteinemia HHcy) are involved in dilated cardiomyopathy. Hcy chelates copper and impairs copper-dependent enzymes. Copper deficiency has been linked to cardiovascular disease. We tested the hypothesis that copper supplement regresses left ventricular hypertrophy (LVH), fibrosis and endothelial dysfunction in pressure overload DCM mice hearts. The mice were grouped as sham, sham + Cu, aortic constriction (AC), and AC + Cu. Aortic constriction was performed by transverse aortic constriction. The mice were treated with or without 20 mg/kg copper supplement in the diet for 12 weeks. The cardiac function was assessed by echocardiography and electrocardiography. The matrix remodeling was assessed by measuring matrix metalloproteinase (MMP), tissue inhibitor of metalloproteinases (TIMPs), and lysyl oxidase (LOX) by Western blot analyses. The results suggest that in AC mice, cardiac function was improved with copper supplement. TIMP-1 levels decreased in AC and were normalized in AC + Cu. Although MMP-9, TIMP-3, and LOX activity increased in AC and returned to baseline value in AC + Cu, copper supplement showed no significant effect on TIMP-4 activity after pressure overload. In conclusion, our data suggest that copper supplement helps improve cardiac function in a pressure overload dilated cardiomyopathic heart. PMID:18679830

Development of Low Cost Contacts to Silicon Solar Cells

NASA Technical Reports Server (NTRS)

Iles, P. A.; Tanner, D. P.

1979-01-01

Different electroless plating systems were evaluated in conjunction with copper electroplating. All tests involved simultaneous deposition of front and back contacts using a standard cell materials. Cells with good adhesion and good curve fill factors were obtained using a palladium-chromium-copper metallization system. The final copper contact system was evaluated to determine if the copper would migrate at elevated temperatures. The copper migrated at elevated temperatures causing cell output degradation.

Integrated metabolomic analysis of the nano-sized copper particle-induced hepatotoxicity and nephrotoxicity in rats: A rapid invivo screening method for nanotoxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lei Ronghui; Department of Public Health, Xi'an Jiaotong University, Xi'an 710061; Wu Chunqi

2008-10-15

Despite an increasing application of copper nanoparticles, there is a serious lack of information concerning their impact on human health and the environment. In this study, the biochemical compositions of urine, serum, and extracts of liver and kidney tissues of rats treated with nano-copper at the different doses (50, 100, and 200 mg/kg/d for 5 d) were investigated using {sup 1}H NMR techniques with the pattern recognition methods. Serum biochemical analysis and histopathological examinations of the liver and kidney of all the rats were simultaneously performed. All the results indicated that the effects produced by nano-copper at a dose ofmore » 100 or 50 mg/kg/d were less than those induced at a higher dose of 200 mg/kg/d. Nano-copper induced overt hepatotoxicity and nephrotoxicity at 200 mg/kg/d for 5 d, which mainly involved scattered dot hepatocytic necrosis and widespread renal proximal tubule necrosis. Increased citrate, succinate, trimethylamine-N-oxide, glucose, and amino acids, accompanied by decreased creatinine levels were observed in the urine; furthermore, elevated levels of lactate, 3-hydroxybutyrate, acetate, creatine, triglycerides, and phosphatide and reduced glucose levels were observed in the serum. The predominant changes identified in the liver tissue aqueous extracts included increased lactate and creatine levels together with reduced glutamine and taurine levels, and the metabolic profile of the kidney tissue aqueous extracts showed an increase in lactate and a drop in glucose. In the chloroform/methanol extracts of the liver and kidney tissues, elevated triglyceride species were identified. These changes suggested that mitochondrial failure, enhanced ketogenesis, fatty acid {beta}-oxidation, and glycolysis contributed to the hepatotoxicity and nephrotoxicity induced by nano-copper at 200 mg/kg/d for 5 d. An increase in triglycerides in the serum, liver and kidney tissues could serve as a potential sensitive biomarker reflecting the lipidosis induced by nano-copper. The data generated from the current study completely supports the fact that an integrated metabolomic approach is promising for the development of a rapid invivo screening method for nanotoxicity.« less

Impact of copper toxicity on stone-head cabbage (Brassica oleracea var. capitata) in hydroponics.

PubMed

Ali, Sajid; Shahbaz, Muhammad; Shahzad, Ahmad Naeem; Khan, Hafiz Azhar Ali; Anees, Moazzam; Haider, Muhammad Saleem; Fatima, Ammara

2015-01-01

Arable soils are frequently subjected to contamination with copper as the consequence of imbalanced fertilization with manure and organic fertilizers and/or extensive use of copper-containing fungicides. In the present study, the exposure of stone-head cabbage (Brassica oleracea var. capitata) to elevated Cu(2+) levels resulted in leaf chlorosis and lesser biomass yield at ≥2 µ M. Root nitrate content was not statistically affected by Cu(2+) levels, although it was substantially decreased at ≥5 µ M Cu(2+) in the shoot. The decrease in nitrate contents can be related to lower nitrate uptake rates because of growth inhibition by Cu-toxicity. Shoot sulfate content increased strongly at ≥2 µ M Cu(2+) indicating an increase in demand for sulfur under Cu stress. Furthermore, at ≥2 µM concentration, concentration of water-soluble non-protein thiol increased markedly in the roots and to a smaller level in the shoot. When exposed to elevated concentrations of Cu(2+) the improved sulfate and water-soluble non-protein thiols need further studies for the evaluation of their direct relation with the synthesis of metal-chelating compounds (i.e., phytochelatins).

Stabilization of Oxidized Copper Nanoclusters in Confined Spaces

DOE PAGES

Akter, Nusnin; Wang, Mengen; Zhong, Jian-Qiang; ...

2018-01-04

Copper is an important industrial catalyst. The ability to manipulate the oxidation state of copper clusters in a controlled way is critical to understanding structure–reactivity relations of copper catalysts at the molecular level. Experimentally, cupric oxide surfaces or even small domains can only be stabilized at elevated temperatures and in the presence of oxygen, as copper can be easily reduced under reaction conditions. Herein bilayer silica films grown on a metallic substrate are used to trap diluted copper oxide clusters. By combining in situ experiments with first principles calculations, it is found that the confined space created by the silicamore » film leads to an increase in the energy barrier for Cu diffusion. Dispersed copper atoms trapped by the silica film can be easily oxidized by surface oxygen chemisorbed on the metallic substrate, which results in the formation and stabilization of Cu 2+ cations.« less

Carbohydrate metabolism in erythrocytes of copper deficient rats.

PubMed

Brooks, S P J; Cockell, K A; Dawson, B A; Ratnayake, W M N; Lampi, B J; Belonje, B; Black, D B; Plouffe, L J

2003-11-01

Dietary copper deficiency is known to adversely affect the circulatory system of fructose-fed rats. Part of the problem may lie in the effect of copper deficiency on intermediary metabolism. To test this, weanling male Long-Evans rats were fed for 4 or 8 weeks on sucrose-based diets containing low or adequate copper content. Copper deficient rats had significantly lower plasma and tissue copper as well as lower plasma copper, zinc-superoxide dismutase activity. Copper deficient rats also had a significantly higher heart:body weight ratio when compared to pair-fed controls. Direct measurement of glycolysis and pentose phosphate pathway flux in erythrocytes using (13)C NMR showed no differences in carbon flux from glucose or fructose to pyruvate but a significantly higher flux through the lactate dehydrogenase locus in copper deficient rats (approximately 1.3 times, average of glucose and glucose + fructose measurements). Copper-deficient animals had significantly higher erythrocyte concentrations of glucose, fructose, glyceraldehyde 3-phosphate and NAD(+). Liver metabolite levels were also affected by copper deficiency being elevated in glycogen and fructose 1-phosphate content. The results show small changes in carbohydrate metabolism of copper deficient rats.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akter, Nusnin; Wang, Mengen; Zhong, Jian-Qiang

Copper is an important industrial catalyst. The ability to manipulate the oxidation state of copper clusters in a controlled way is critical to understanding structure–reactivity relations of copper catalysts at the molecular level. Experimentally, cupric oxide surfaces or even small domains can only be stabilized at elevated temperatures and in the presence of oxygen, as copper can be easily reduced under reaction conditions. Herein bilayer silica films grown on a metallic substrate are used to trap diluted copper oxide clusters. By combining in situ experiments with first principles calculations, it is found that the confined space created by the silicamore » film leads to an increase in the energy barrier for Cu diffusion. Dispersed copper atoms trapped by the silica film can be easily oxidized by surface oxygen chemisorbed on the metallic substrate, which results in the formation and stabilization of Cu 2+ cations.« less

Mining legacy across a wetland landscape: high mercury in Upper Peninsula (Michigan) rivers, lakes, and fish.

PubMed

Kerfoot, W Charles; Urban, Noel R; McDonald, Cory P; Zhang, Huanxin; Rossmann, Ronald; Perlinger, Judith A; Khan, Tanvir; Hendricks, Ashley; Priyadarshini, Mugdha; Bolstad, Morgan

2018-04-25

A geographic enigma is that present-day atmospheric deposition of mercury in the Upper Peninsula of Michigan is low (48%) and that regional industrial emissions have declined substantially (ca. 81% reduction) relative to downstate. Mercury levels should be declining. However, state (MDEQ) surveys of rivers and lakes revealed elevated total mercury (THg) in Upper Peninsula waters and sediment relative to downstate. Moreover, Western Upper Peninsula (WUP) fish possess higher methyl mercury (MeHg) levels than Northern Lower Peninsula (NLP) fish. A contributing explanation for elevated THg loading is that a century ago the Upper Peninsula was a major industrial region, centered on mining. Many regional ores (silver, copper, zinc, massive sulfides) contain mercury in part per million concentrations. Copper smelters and iron furnace-taconite operations broadcast mercury almost continuously for 140 years, whereas mills discharged tailings and old mine shafts leaked contaminated water. We show that mercury emissions from copper and iron operations were substantial (60-650 kg per year) and dispersed over relatively large areas. Moreover, lake sediments in the vicinity of mining operations have higher THg concentrations. Sediment profiles from the Keweenaw Waterway show that THg accumulation increased 50- to 400-fold above modern-day atmospheric deposition levels during active mining and smelting operations, with lingering MeHg effects. High MeHg concentrations are geographically correlated with low pH and dissolved organic carbon (DOC), a consequence of biogeochemical cycling in wetlands, characteristic of the Upper Peninsula. DOC can mobilize metals and elevate MeHg concentrations. We argue that mercury loading from mining is historically superimposed upon strong regional wetland effects, producing a combined elevation of both THg and MeHg in the Western Upper Peninsula.

Influence of Dietary Copper on Serum Growth-Related Hormone Levels and Growth Performance of Weanling Pigs.

PubMed

Wang, Jianguo; Zhu, Xiaoyan; Guo, Yazhou; Wang, Zhe; Zhao, Baoyu; Yin, Yunhou; Liu, Guowen

2016-07-01

To investigate the effect of dietary copper on serum growth-related hormones levels and growth performance, a total of 60 weanling pigs were randomly assigned to six groups each containing 10 pigs, fed on basal diets supplemented with 0 (control), 100, 150, 200, 250, and 300 mg/kg copper sulfate for 80 days, respectively. The average daily gain (ADG), feed to gain ratio (F/G), feed intake and serum growth hormone (GH), insulin (INS), insulin-like growth factor 1 (IGF-1), and insulin-like growth factor-binding protein 3 (IGFBP-3) levels were detected at interval of 20 days. The results revealed that ADG, and serum GH, INS, IGF-1, and IGFBP-3 concentrations were increased significantly in the pigs fed on diets added with 100, 150, 200, 250, and 300 mg/kg copper sulfate. Meanwhile, in the pigs supplemented with 250 mg/kg copper sulfate, ADG was increased significantly from the 40th to the 60th day of the experiment (P < 0.01), and the levels of GH, INS, IGF-1, and IGFBP-3 in serum were elevated significantly from the 20th to the 40th day of the experiment (P < 0.01). It is concluded that effects of copper supplemented in the diet on the growth of pigs were related to the increasing levels of GH, INS, IGF-1, and IGFBP-3 in serum which were induced by copper. High dietary copper increase the concentrations of growth-related hormones in serum, resulting in improving the growth performance of weanling pigs.

Copper-complexing ligands produced by an intact estuarine microbial community in response to copper stress.

NASA Astrophysics Data System (ADS)

Bingham, J.; Dryden, C.; Gordon, A.

2002-12-01

Copper is both an important nutrient and a pollutant in the marine environment. By studying the interactions between microorganisms and copper in the Elizabeth River (VA), home to a major Naval Base, we field tested the hypothesis that picoplankton and/or bacterioplankton produce strong, copper-complexing ligands in response to elevated copper concentrations. A simple light/ dark test was used to distinguish between heterotrophic and phototrophic ligand production. Samples were bottled and moored, submerged one meter, for a week. Direct counts using DAPI stain and epiflourescence were conducted to find concentrations of picoplankton and bacterioplankton. Using cathodic stripping voltammetry, we found the total copper concentrations, and then from a titration of the ligands by copper, the ligand concentrations and conditional stability constants were obtained. The Elizabeth River naturally had between 10-20 nM total dissolved copper concentrations. However when copper complexation was considered we found that the levels of bio-available Cu(II) ions were much lower. In fact in the natural samples the levels were not high enough to affect the relative reproductive rates of several microorganisms. Naturally there was a 50 nM "buffer zone" of ligand to total dissolved copper concentration. Furthermore, when stressed with excess copper, healthy picoplankton produced enough ligand to alleviate toxicity, and rebuild the buffer zone. However bacterioplankton only produced enough ligand so that they were no longer affected. Therefore, intact estuarine communities regulate copper bioavailability and toxicity with ligand production.

Iron plaque formation and heavy metal uptake in Spartina alterniflora at different tidal levels and waterlogging conditions.

PubMed

Xu, Yan; Sun, Xiangli; Zhang, Qiqiong; Li, Xiuzhen; Yan, Zhongzheng

2018-05-30

Tidal flat elevation in the estuarine wetland determines the tidal flooding time and flooding frequency, which will inevitably affect the formation of iron plaque and accumulations of heavy metals (HMs) in wetland plants. The present study investigated the formation of iron plaque and HM's (copper, zinc, lead, and chromium) accumulation in S. alterniflora, a typical estuarine wetland species, at different tidal flat elevations (low, middle and high) in filed and at different time (3, 6, 9, 12 h per day) of waterlogging treatment in greenhouse conditions. Results showed that the accumulation of copper, zinc, lead, and chromium in S. alterniflora was proportional to the exchangeable fraction of these metals in the sediments, which generally increased with the increase of waterlogging time, whereas the formations of iron plaque in roots decreased with the increase of waterlogging time. Under field conditions, the uptake of copper and zinc in the different parts of the plants generally increased with the tidal levels despite the decrease in the metals' exchangeable fraction with increasing tidal levels. The formation of iron plaque was found to be highest in the middle tidal positions and significantly lower in low and high tidal positions. Longer waterlogging time increased the metals' accumulation but decreased the formation of iron plaque in S. alterniflora. The binding of metal ions on iron plaque helped impede the uptake and accumulation of copper and chromium in S. alterniflora. Copyright © 2018 Elsevier Inc. All rights reserved.

Copper and zinc content in wild game shot with lead or non-lead ammunition – implications for consumer health protection

PubMed Central

Sommerfeld, Christine; Müller-Graf, Christine; Selhorst, Thomas; Greiner, Matthias; Gerofke, Antje; Ulbig, Ellen; Gremse, Carl; Spolders, Markus; Schafft, Helmut; Lahrssen-Wiederholt, Monika

2017-01-01

The aim of this study was to examine the contamination of game meat with copper and zinc and establish whether the use of alternative (non-lead) ammunition can lead to higher or unsafe levels of copper and zinc in the meat of roe deer, wild boar and red deer. The research project “Safety of game meat obtained through hunting” (LEMISI) was conducted in Germany with the purpose of examining the entry of lead as well as copper and zinc into the meat of hunted game when using either lead or non-lead ammunition. The outcome of this study shows that the usage of both lead-based ammunition and alternative non-lead ammunition results in the entry of copper and zinc into the edible parts of the game. Using non-lead ammunition does not entail dangerously elevated levels of copper and zinc, so replacing lead ammunition with alternative ammunition does not introduce a further health problem with regard to these metals. The levels of copper and zinc in game meat found in this study are in the range found in previous studies of game. The content of copper and zinc in game meat is also comparable to those regularly detected in meat and its products from livestock (pig, cattle, sheep) for which the mean human consumption rate is much higher. From the viewpoint of consumer health protection, the use of non-lead ammunition does not pose an additional hazard through copper and zinc contamination. A health risk due to the presence of copper and zinc in game meat at typical levels of consumer exposure is unlikely for both types of ammunition. PMID:28934259

Copper and zinc content in wild game shot with lead or non-lead ammunition - implications for consumer health protection.

PubMed

Schlichting, Daniela; Sommerfeld, Christine; Müller-Graf, Christine; Selhorst, Thomas; Greiner, Matthias; Gerofke, Antje; Ulbig, Ellen; Gremse, Carl; Spolders, Markus; Schafft, Helmut; Lahrssen-Wiederholt, Monika

2017-01-01

The aim of this study was to examine the contamination of game meat with copper and zinc and establish whether the use of alternative (non-lead) ammunition can lead to higher or unsafe levels of copper and zinc in the meat of roe deer, wild boar and red deer. The research project "Safety of game meat obtained through hunting" (LEMISI) was conducted in Germany with the purpose of examining the entry of lead as well as copper and zinc into the meat of hunted game when using either lead or non-lead ammunition. The outcome of this study shows that the usage of both lead-based ammunition and alternative non-lead ammunition results in the entry of copper and zinc into the edible parts of the game. Using non-lead ammunition does not entail dangerously elevated levels of copper and zinc, so replacing lead ammunition with alternative ammunition does not introduce a further health problem with regard to these metals. The levels of copper and zinc in game meat found in this study are in the range found in previous studies of game. The content of copper and zinc in game meat is also comparable to those regularly detected in meat and its products from livestock (pig, cattle, sheep) for which the mean human consumption rate is much higher. From the viewpoint of consumer health protection, the use of non-lead ammunition does not pose an additional hazard through copper and zinc contamination. A health risk due to the presence of copper and zinc in game meat at typical levels of consumer exposure is unlikely for both types of ammunition.

Bioaccumulation of metals in plants, arthropods, and mice at a seasonal wetland.

PubMed

Torres, K C; Johnson, M L

2001-11-01

Concentrations of arsenic, cadmium, copper, lead, and nickel were measured in soils, house mice (Mus musculus), and the main food items of this omnivorous mouse to examine the occurrence of these metals in selected components of a seasonal wetland. Soil concentrations of copper, lead, and (in some areas) nickel were elevated, but extractable soil concentrations indicated low bioavailability of metals. Levels of most metals in mice and composited arthropods were consistent with reference site concentrations from other studies. However, copper was found to be particularly mobile within the local ecosystem and accumulated in house mouse carcasses and composited arthropods at substantial levels. Metal residues in Scirpus robustus (alkali bulrush) roots exceeded those in seeds, consistent with patterns of bioaccumulation commonly observed in plants. Uptake and bioaccumulation factors for S. robustus seeds and roots, arthropods, and mouse carcasses and livers are reported. Concentrations of lead and nickel in S. robustus roots exhibited significant linear relationships with levels in soils. Copper levels in S. robustus seeds varied significantly with those in house mouse livers, suggesting that trophic transfer of copper from this food source to mice occurred. However, other spatial patterns of bioaccumulation in S. robustus and house mice relative to soil/seed concentrations were absent. Metal levels in house mice bore no relation to body weight or estimated age.

Trace elements and organic compounds in streambed sediment and aquatic biota from the Sacramento River Basin, California, October and November 1995

USGS Publications Warehouse

MacCoy, Dorene E.; Domagalski, Joseph L.

1999-01-01

Elevated levels of trace elements and hydrophobic organic compounds were detected in streambed sediments and aquatic biota [Asiatic clam (Corbicula fluminea) or bottom-feeding fish] of the Sacramento River Basin, California, during October and November 1995. Trace elements detected included cadmium, copper, mercury, lead, and zinc. Elevated levels of cadmium, copper, and zinc in the upper Sacramento River are attributed to a mining land use, and elevated levels of zinc and lead in an urban stream, and possibly in the lower Sacramento River, are attributed to urban runoff processes. Elevated levels of mercury in streambed sediment are attributed to either past mercury mining or to the use of mercury in past gold mining operations. Mercury mining was an important land use within the Coast Ranges in the past and gold mining was an important land use of the Sierra Nevada in the past. Mercury was the only trace element found in elevated levels in the tissue of aquatic biota, and those levels also could be attributed to either mining or urban runoff. Hydrophobic organic compounds also were detected in streambed sediments and aquatic biota. The most frequently detected compounds were DDT and its breakdown products, dieldrin, oxychlordane, and toxaphene. Differences were found in the types of compounds detected at agricultural sites and the urban site. Although both types of sites had measurable concentrations of DDT or its breakdown products, the urban site also had measurable concentrations of pesticides used for household pest control. Few semivolatile compounds were detected in the streambed sediments of any site. The semivolatile compound p-cresol, a coal-tar derivative associated with road maintenance, was found in the highest concentration.

Does Dietary Copper Supplementation enhance or diminish PCB126 Toxicity in Rodent Liver?

PubMed Central

Lai, Ian K.; Klaren, William D.; Li, Miao; Wels, Brian; Simmons, Donald L.; Olivier, Alicia K.; Haschek, Wanda M.; Wang, Kai; Ludewig, Gabriele; Robertson, Larry W.

2013-01-01

Copper is essential for the function of the mitochondrial electron transport chain and several antioxidant proteins. However, in its free form copper can participate in Fenton-like reactions that produce reactive hydroxyl radicals. Aryl-hydrocarbon receptor (AhR) agonists, including the most potent polychlorinated biphenyl (PCB) congener, 3,3',4,4',5-pentachlorobiphenyl (PCB126), increase copper levels in rodent livers. This is accompanied by biochemical and toxic changes. To assess the involvement of copper in PCB toxicity, male Sprague Dawley rats were fed an AIN-93G diet with differing dietary copper levels: low (2 ppm), adequate (6 ppm), and high (10 ppm). After three weeks, rats from each group were given a single ip injection of corn oil (control), 1, or 5 μmol/kg body weight PCB126. Two weeks following injections, biochemical and morphological markers of hepatic toxicity, trace metal status, and hepatic gene expression of metalloproteins were evaluated. Increasing dietary copper was associated with elevated tissue levels of copper and ceruloplasmin. In the livers of PCB126-treated rats the hallmark signs of AhR activation were present, including increased cytochrome P-450 and lipid levels, and decreased glutathione. In addition a doubling of hepatic copper levels was seen and overall metals homeostasis was disturbed, resulting in decreased hepatic selenium, manganese, zinc and iron. Expression of key metalloproteins was either decreased (cytochrome c oxidase), unchanged (ceruloplasmin and CuZnSOD) or increased (tyrosinase, metallothionein 1 and 2) with exposure to PCB126. Increases in metallothionein may contribute/reflect the increased copper seen. Alterations in dietary copper did not amplify or abrogate the hepatic toxicity of PCB126. PCB126 toxicity, i.e. oxidative stress and steatosis, is clearly associated with disturbed metals homeostasis. Understanding the mechanisms of this disturbance may provide tools to prevent liver toxicity by other AhR agonists. PMID:23527585

ATP7B mediates vesicular sequestration of copper: insight into biliary copper excretion.

PubMed

Cater, Michael A; La Fontaine, Sharon; Shield, Kristy; Deal, Yolanda; Mercer, Julian F B

2006-02-01

The Wilson protein (ATP7B) regulates levels of systemic copper by excreting excess copper into bile. It is not clear whether ATP7B translocates excess intrahepatic copper directly across the canalicular membrane or sequesters this copper into exocytic vesicles, which subsequently fuse with canalicular membrane to expel their contents into bile. The aim of this study was to clarify the mechanism underlying ATP7B-mediated copper detoxification by investigating endogenous ATP7B localization in the HepG2 hepatoma cell line and its ability to mediate vesicular sequestration of excess intracellular copper. Immunofluorescence microscopy was used to investigate the effect of copper concentration on the localization of endogenous ATP7B in HepG2 cells. Copper accumulation studies to determine whether ATP7B can mediate vesicular sequestration of excess intracellular copper were performed using Chinese hamster ovary cells that exogenously expressed wild-type and mutant ATP7B proteins. In HepG2 cells, elevated copper levels stimulated trafficking of ATP7B to pericanalicular vesicles and not to the canalicular membrane as previously reported. Mutation of an endocytic retrieval signal in ATP7B caused the protein to constitutively localize to vesicles and not to the plasma membrane, suggesting that a vesicular compartment(s) is the final trafficking destination for ATP7B. Expression of wild-type and mutant ATP7B caused Chinese hamster ovary cells to accumulate copper in vesicles, which subsequently undergo exocytosis, releasing copper across the plasma membrane. This report provides compelling evidence that the primary mechanism of biliary copper excretion involves ATP7B-mediated vesicular sequestration of copper rather than direct copper translocation across the canalicular membrane.

Occurrence of the Transferable Copper Resistance Gene tcrB among Fecal Enterococci of U.S. Feedlot Cattle Fed Copper-Supplemented Diets

PubMed Central

Amachawadi, R. G.; Alvarado, C. A.; Mainini, T. R.; Vinasco, J.; Drouillard, J. S.; Nagaraja, T. G.

2013-01-01

Copper, an essential micronutrient, is supplemented in the diet at elevated levels to reduce morbidity and mortality and to promote growth in feedlot cattle. Gut bacteria exposed to copper can acquire resistance, which among enterococci is conferred by a transferable copper resistance gene (tcrB) borne on a plasmid. The present study was undertaken to investigate whether the feeding of copper at levels sufficient to promote growth increases the prevalence of the tcrB gene among the fecal enterococci of feedlot cattle. The study was performed with 261 crossbred yearling heifers housed in 24 pens, with pens assigned randomly to a 2×2 factorial arrangement of treatments consisting of dietary copper and a commercial linseed meal-based energy protein supplement. A total of 22 isolates, each identified as Enterococcus faecium, were positive for tcrB with an overall prevalence of 3.8% (22/576). The prevalence was higher among the cattle fed diets supplemented with copper (6.9%) compared to normal copper levels (0.7%). The tcrB-positive isolates always contained both erm(B) and tet(M) genes. Median copper MICs for tcrB-positive and tcrB-negative enterococci were 22 and 4 mM, respectively. The transferability of the tcrB gene was demonstrated via a filter-mating assay. Multilocus variable number tandem repeat analysis revealed a genetically diverse population of enterococci. The finding of a strong association between the copper resistance gene and other antibiotic (tetracycline and tylosin) resistance determinants is significant because enterococci remain potential pathogens and have the propensity to transfer resistance genes to other bacteria in the gut. PMID:23666328

Subchronic treatment of rats with aurothioglucose; effects on plasma, hepatic, renal and urinary zinc, copper and metallothionein.

PubMed

McVety, K J; Shaikh, Z A

1987-11-01

Administration of sodium aurothioglucose (10 mg/kg per day) to female rats for up to 8 weeks resulted in no apparent effects on the kidney. Gold accumulated in kidney, liver, spleen, pancreas, skin and blood. Although plasma and hepatic gold levels increased with time, no remarkable change in either copper, zinc or metallothionein (MT) levels was observed. Gel filtration chromatography of plasma showed binding of gold to albumin, whereas copper was associated with albumin, ceruloplasmin and a protein eluting in the void volume of the Sephadex G-150 column. Almost all of the hepatic gold was bound to proteins other than MT. In the kidney, not only gold but also copper and MT increased rapidly, reached a maximum between 2 and 4 weeks and exhibited insignificant change thereafter. Gold-treated animals showed an increase in binding of copper to the very high molecular weight plasma protein, which may be involved in transport of copper to the kidneys. Urinary gold and MT followed a pattern similar to that in the kidney. Renal zinc also increased but returned to normal by week 8. In renal cytosol 57% and 54% of the gold and copper, respectively, were associated with MT. It appears that the elevated levels of copper and zinc, rather than gold, are responsible for the induction of MT synthesis. This then provides a mechanism by which gold and the inducing metals are retained by the kidney.

Molecular control of copper homeostasis in filamentous fungi: increased expression of a metallothionein gene during aging of Podospora anserina.

PubMed

Averbeck, N B; Borghouts, C; Hamann, A; Specke, V; Osiewacz, H D

2001-01-01

The lifespan of the ascomycete Podospora anserina was previously demonstrated to be significantly increased in a copper-uptake mutant, suggesting that copper is a potential stressor involved in degenerative processes. In order to determine whether changes in copper stress occur in the cells during normal aging of cultures, we cloned and characterized a gene coding for a component of the molecular machinery involved in the control of copper homeostasis. This gene, PaMt1, is a single-copy gene that encodes a metallothionein of 26 amino acids. The coding sequence of PaMt1 is interrupted by a single intron. The deduced amino acid sequence shows a high degree of sequence identity to metallothioneins of the filamentous ascomycete Neurospora crassa and the basidiomycete Agaricus bisporus, and to the N-terminal portion of mammalian metallothioneins. Levels of PaMt1 transcript increase in response to elevated amounts of copper in the growth medium and during aging of wild-type cultures. In contrast, in the long-lived mutant grisea, transcript levels first increase but then decrease again. The ability of wild-type cultures to respond to exogenous copper stress via the induction of PaMt1 transcription is not affected as they grow older.

Elemental properties of copper slag and measured airborne exposures at a copper slag processing facility.

PubMed

Mugford, Christopher; Gibbs, Jenna L; Boylstein, Randy

2017-08-01

In 1974, the National Institute for Occupational Safety and Health recommended a ban on the use of abrasives containing >1% silica, giving rise to abrasive substitutes like copper slag. We present results from a National Institute for Occupational Safety and Health industrial hygiene survey at a copper slag processing facility that consisted of the collection of bulk samples for metals and silica; and full-shift area and personal air samples for dust, metals, and respirable silica. Carcinogens, suspect carcinogens, and other toxic elements were detected in all bulk samples, and area and personal air samples. Area air samples identified several areas with elevated levels of inhalable and respirable dust, and respirable silica: quality control check area (236 mg/m 3 inhalable; 10.3 mg/m 3 respirable; 0.430 mg/m 3 silica), inside the screen house (109 mg/m 3 inhalable; 13.8 mg/m 3 respirable; 0.686 mg/m 3 silica), under the conveyor belt leading to the screen house (19.8 mg/m 3 inhalable), and inside a conveyor access shack (11.4 mg/m 3 inhalable; 1.74 mg/m 3 respirable; 0.067 mg/m 3 silica). Overall, personal dust samples were lower than area dust samples and did not exceed published occupational exposure limits. Silica samples collected from a plant hand and a laborer exceeded the American Conference of Governmental Industrial Hygienist Threshold Limit Value of 0.025 µg/m 3 . All workers involved in copper slag processing (n = 5) approached or exceeded the Occupational Safety and Health Administration permissible exposure limit of 10 µg/m 3 for arsenic (range: 9.12-18.0 µg/m 3 ). Personal total dust levels were moderately correlated with personal arsenic levels (R s = 0.70) and personal respirable dust levels were strongly correlated with respirable silica levels (R s = 0.89). We identified multiple areas with elevated levels of dust, respirable silica, and metals that may have implications for personal exposure at other facilities if preventive measures are not taken. To our knowledge, this is the first attempt to characterize exposures associated with copper slag processing. More in-depth air monitoring and health surveillance is needed to understand occupational exposures and health outcomes in this industry.

The Activity of Menkes Disease Protein ATP7A Is Essential for Redox Balance in Mitochondria.

PubMed

Bhattacharjee, Ashima; Yang, Haojun; Duffy, Megan; Robinson, Emily; Conrad-Antoville, Arianrhod; Lu, Ya-Wen; Capps, Tony; Braiterman, Lelita; Wolfgang, Michael; Murphy, Michael P; Yi, Ling; Kaler, Stephen G; Lutsenko, Svetlana; Ralle, Martina

2016-08-05

Copper-transporting ATPase ATP7A is essential for mammalian copper homeostasis. Loss of ATP7A activity is associated with fatal Menkes disease and various other pathologies. In cells, ATP7A inactivation disrupts copper transport from the cytosol into the secretory pathway. Using fibroblasts from Menkes disease patients and mouse 3T3-L1 cells with a CRISPR/Cas9-inactivated ATP7A, we demonstrate that ATP7A dysfunction is also damaging to mitochondrial redox balance. In these cells, copper accumulates in nuclei, cytosol, and mitochondria, causing distinct changes in their redox environment. Quantitative imaging of live cells using GRX1-roGFP2 and HyPer sensors reveals highest glutathione oxidation and elevation of H2O2 in mitochondria, whereas the redox environment of nuclei and the cytosol is much less affected. Decreasing the H2O2 levels in mitochondria with MitoQ does not prevent glutathione oxidation; i.e. elevated copper and not H2O2 is a primary cause of glutathione oxidation. Redox misbalance does not significantly affect mitochondrion morphology or the activity of respiratory complex IV but markedly increases cell sensitivity to even mild glutathione depletion, resulting in loss of cell viability. Thus, ATP7A activity protects mitochondria from excessive copper entry, which is deleterious to redox buffers. Mitochondrial redox misbalance could significantly contribute to pathologies associated with ATP7A inactivation in tissues with paradoxical accumulation of copper (i.e. renal epithelia). © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

The Activity of Menkes Disease Protein ATP7A Is Essential for Redox Balance in Mitochondria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhattacharjee, Ashima; Yang, Haojun; Duffy, Megan

Copper-transporting ATPase ATP7A is essential for mammalian copper homeostasis. Loss of ATP7A activity is associated with fatal Menkes disease and various other pathologies. In cells, ATP7A inactivation disrupts copper transport from the cytosol into the secretory pathway. Using fibroblasts from Menkes disease patients and mouse 3T3-L1 cells with a CRISPR/Cas9-inactivated ATP7A, we demonstrate that ATP7A dysfunction is also damaging to mitochondrial redox balance. In these cells, copper accumulates in nuclei, cytosol, and mitochondria, causing distinct changes in their redox environment. Quantitative imaging of live cells using GRX1-roGFP2 and HyPer sensors reveals highest glutathione oxidation and elevation of H2O2 in mitochondria,more » whereas the redox environment of nuclei and the cytosol is much less affected. Decreasing the H2O2 levels in mitochondria with MitoQ does not prevent glutathione oxidation; i.e. elevated copper and not H2O2 is a primary cause of glutathione oxidation. Redox misbalance does not significantly affect mitochondrion morphology or the activity of respiratory complex IV but markedly increases cell sensitivity to even mild glutathione depletion, resulting in loss of cell viability. Thus, ATP7A activity protects mitochondria from excessive copper entry, which is deleterious to redox buffers. Mitochondrial redox misbalance could significantly contribute to pathologies associated with ATP7A inactivation in tissues with paradoxical accumulation of copper (i.e. renal epithelia).« less

The Activity of Menkes Disease Protein ATP7A Is Essential for Redox Balance in Mitochondria*

PubMed Central

Bhattacharjee, Ashima; Yang, Haojun; Duffy, Megan; Robinson, Emily; Conrad-Antoville, Arianrhod; Lu, Ya-Wen; Capps, Tony; Braiterman, Lelita; Wolfgang, Michael; Murphy, Michael P.; Yi, Ling; Kaler, Stephen G.; Lutsenko, Svetlana; Ralle, Martina

2016-01-01

Copper-transporting ATPase ATP7A is essential for mammalian copper homeostasis. Loss of ATP7A activity is associated with fatal Menkes disease and various other pathologies. In cells, ATP7A inactivation disrupts copper transport from the cytosol into the secretory pathway. Using fibroblasts from Menkes disease patients and mouse 3T3-L1 cells with a CRISPR/Cas9-inactivated ATP7A, we demonstrate that ATP7A dysfunction is also damaging to mitochondrial redox balance. In these cells, copper accumulates in nuclei, cytosol, and mitochondria, causing distinct changes in their redox environment. Quantitative imaging of live cells using GRX1-roGFP2 and HyPer sensors reveals highest glutathione oxidation and elevation of H2O2 in mitochondria, whereas the redox environment of nuclei and the cytosol is much less affected. Decreasing the H2O2 levels in mitochondria with MitoQ does not prevent glutathione oxidation; i.e. elevated copper and not H2O2 is a primary cause of glutathione oxidation. Redox misbalance does not significantly affect mitochondrion morphology or the activity of respiratory complex IV but markedly increases cell sensitivity to even mild glutathione depletion, resulting in loss of cell viability. Thus, ATP7A activity protects mitochondria from excessive copper entry, which is deleterious to redox buffers. Mitochondrial redox misbalance could significantly contribute to pathologies associated with ATP7A inactivation in tissues with paradoxical accumulation of copper (i.e. renal epithelia). PMID:27226607

Copper Tolerance and Characterization of a Copper-Responsive Operon, copYAZ, in an M1T1 Clinical Strain of Streptococcus pyogenes

PubMed Central

Gordon, Lily D.; Fang, Zhong; Holder, Robert C.; Reid, Sean D.

2015-01-01

ABSTRACT Infection with Streptococcus pyogenes is associated with a breadth of clinical manifestations ranging from mild pharyngitis to severe necrotizing fasciitis. Elevated levels of intracellular copper are highly toxic to this bacterium, and thus, the microbe must tightly regulate the level of this metal ion by one or more mechanisms, which have, to date, not been clearly defined. In this study, we have identified two virulence mechanisms by which S. pyogenes protects itself against copper toxicity. We defined a set of putative genes, copY (for a regulator), copA (for a P1-type ATPase), and copZ (for a copper chaperone), whose expression is regulated by copper. Our results indicate that these genes are highly conserved among a range of clinical S. pyogenes isolates. The copY, copA, and copZ genes are induced by copper and are transcribed as a single unit. Heterologous expression assays revealed that S. pyogenes CopA can confer copper tolerance in a copper-sensitive Escherichia coli mutant by preventing the accumulation of toxic levels of copper, a finding that is consistent with a role for CopA in copper export. Evaluation of the effect of copper stress on S. pyogenes in a planktonic or biofilm state revealed that biofilms may aid in protection during initial exposure to copper. However, copper stress appears to prevent the shift from the planktonic to the biofilm state. Therefore, our results indicate that S. pyogenes may use several virulence mechanisms, including altered gene expression and a transition to and from planktonic and biofilm states, to promote survival during copper stress. IMPORTANCE Bacterial pathogens encounter multiple stressors at the host-pathogen interface. This study evaluates a virulence mechanism(s) utilized by S. pyogenes to combat copper at sites of infection. A better understanding of pathogen tolerance to stressors such as copper is necessary to determine how host-pathogen interactions impact bacterial survival during infections. These insights may lead to the identification of novel therapeutic targets that can be used to address antibiotic resistance. PMID:26013489

Copper Tolerance and Characterization of a Copper-Responsive Operon, copYAZ, in an M1T1 Clinical Strain of Streptococcus pyogenes.

PubMed

Young, Christie A; Gordon, Lily D; Fang, Zhong; Holder, Robert C; Reid, Sean D

2015-08-01

Infection with Streptococcus pyogenes is associated with a breadth of clinical manifestations ranging from mild pharyngitis to severe necrotizing fasciitis. Elevated levels of intracellular copper are highly toxic to this bacterium, and thus, the microbe must tightly regulate the level of this metal ion by one or more mechanisms, which have, to date, not been clearly defined. In this study, we have identified two virulence mechanisms by which S. pyogenes protects itself against copper toxicity. We defined a set of putative genes, copY (for a regulator), copA (for a P1-type ATPase), and copZ (for a copper chaperone), whose expression is regulated by copper. Our results indicate that these genes are highly conserved among a range of clinical S. pyogenes isolates. The copY, copA, and copZ genes are induced by copper and are transcribed as a single unit. Heterologous expression assays revealed that S. pyogenes CopA can confer copper tolerance in a copper-sensitive Escherichia coli mutant by preventing the accumulation of toxic levels of copper, a finding that is consistent with a role for CopA in copper export. Evaluation of the effect of copper stress on S. pyogenes in a planktonic or biofilm state revealed that biofilms may aid in protection during initial exposure to copper. However, copper stress appears to prevent the shift from the planktonic to the biofilm state. Therefore, our results indicate that S. pyogenes may use several virulence mechanisms, including altered gene expression and a transition to and from planktonic and biofilm states, to promote survival during copper stress. Bacterial pathogens encounter multiple stressors at the host-pathogen interface. This study evaluates a virulence mechanism(s) utilized by S. pyogenes to combat copper at sites of infection. A better understanding of pathogen tolerance to stressors such as copper is necessary to determine how host-pathogen interactions impact bacterial survival during infections. These insights may lead to the identification of novel therapeutic targets that can be used to address antibiotic resistance. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Evidence for widespread, severe brain copper deficiency in Alzheimer's dementia.

PubMed

Xu, Jingshu; Church, Stephanie J; Patassini, Stefano; Begley, Paul; Waldvogel, Henry J; Curtis, Maurice A; Faull, Richard L M; Unwin, Richard D; Cooper, Garth J S

2017-08-16

Datasets comprising simultaneous measurements of many essential metals in Alzheimer's disease (AD) brain are sparse, and available studies are not entirely in agreement. To further elucidate this matter, we employed inductively-coupled-plasma mass spectrometry to measure post-mortem levels of 8 essential metals and selenium, in 7 brain regions from 9 cases with AD (neuropathological severity Braak IV-VI), and 13 controls who had normal ante-mortem mental function and no evidence of brain disease. Of the regions studied, three undergo severe neuronal damage in AD (hippocampus, entorhinal cortex and middle-temporal gyrus); three are less-severely affected (sensory cortex, motor cortex and cingulate gyrus); and one (cerebellum) is relatively spared. Metal concentrations in the controls differed among brain regions, and AD-associated perturbations in most metals occurred in only a few: regions more severely affected by neurodegeneration generally showed alterations in more metals, and cerebellum displayed a distinctive pattern. By contrast, copper levels were substantively decreased in all AD-brain regions, to 52.8-70.2% of corresponding control values, consistent with pan-cerebral copper deficiency. This copper deficiency could be pathogenic in AD, since levels are lowered to values approximating those in Menkes' disease, an X-linked recessive disorder where brain-copper deficiency is the accepted cause of severe brain damage. Our study reinforces others reporting deficient brain copper in AD, and indicates that interventions aimed at safely and effectively elevating brain copper could provide a new experimental-therapeutic approach.

Interactions between accumulated copper, bacterial community structure and histamine levels in crayfish meat during storage.

PubMed

Soedarini, Bernadeta; van Gestel, Cornelis A M; van Straalen, Nico M; Widianarko, Budi; Röling, Wilfred F M

2014-08-01

Pollution in aquaculture areas may negatively impact edible species and threaten seafood quality and safety. The aim of this study was to determine the interaction between copper and bacteria in the aquatic habitat and their impact upon crustaceans. Marbled crayfish was chosen as a model of aquatic crustaceans and the influence of metal contamination on bacterial community structure in water used to culture crayfish and in crayfish themselves was investigated. Histamine, an allergen commonly formed by certain groups of bacteria in crustacean edible tissue during storage, was also determined. Copper exposure increased its concentration in crayfish meat by 17.4%, but the copper concentration remained within acceptable food safety limits. Elevated copper levels affected the bacterial community both in the water used to cultivate crayfish and in the marbled crayfish themselves. Cluster analysis of 16S rRNA-gene based microbial community fingerprints revealed that copper impacted the bacterial community in the water and in the crayfish meat. However, copper exposure reduced the formation of histamine in crayfish meat during storage by 66.3%. Copper from the habitat appears to reduce histamine accumulation in crayfish meat during storage by affecting the bacterial community structure of the cultivation water and most likely also in the intestine of the crayfish. From a food safety point of view, copper treatment during the aqua culturing of crustaceans has a positive impact on the postharvest stage. © 2013 Society of Chemical Industry.

Copper tolerance in Frankia sp. strain EuI1c involves surface binding and copper transport.

PubMed

Rehan, Medhat; Furnholm, Teal; Finethy, Ryan H; Chu, Feixia; El-Fadly, Gomaah; Tisa, Louis S

2014-09-01

Several Frankia strains have been shown to be copper-tolerant. The mechanism of their copper tolerance was investigated for Frankia sp. strain EuI1c. Copper binding was shown by binding studies. Unusual globular structures were observed on the surface of the bacterium. These globular structures were composed of aggregates containing many relatively smaller "leaf-like" structures. Scanning electron microscopy with energy-dispersive X-ray (SEM-EDAX) analysis of these structures indicated elevated copper and phosphate levels compared to the control cells. Fourier transform infrared spectroscopy (FTIR) analysis indicated an increase in extracellular phosphate on the cell surface of copper-stressed cells. Bioinformatics' analysis of the Frankia sp. strain EuI1c genome revealed five potential cop genes: copA, copZ, copC, copCD, and copD. Experiments with Frankia sp. strain EuI1c using qRT-PCR indicated an increase in messenger RNA (mRNA) levels of the five cop genes upon Cu(2+) stress. After 5 days of Cu(2+) stress, the copA, copZ, copC, copCD, and copD mRNA levels increased 25-, 8-, 18-, 18-, and 25-fold, respectively. The protein profile of Cu(2+)-stressed Frankia sp. strain EuI1c cells revealed the upregulation of a 36.7 kDa protein that was identified as FraEuI1c_1092 (sulfate-binding periplasmic transport protein). Homologues of this gene were only present in the genomes of the Cu(2+)-resistant Frankia strains (EuI1c, DC12, and CN3). These data indicate that copper tolerance by Frankia sp. strain EuI1c involved the binding of copper to the cell surface and transport proteins.

Detection and Evaluation of Elevated Lead Release from Service Lines: A Field Study

EPA Science Inventory

Comparative stagnation sampling conducted in 32 homes in Chicago, Illinois with lead service (LSLs) demonstrated that the existing regulatory sampling protocol under the U. S. Lead and Copper Rule (LCR) systematically underestimated lead corrosion. Lead levels were highest within...

Copper and zinc runoff from land application of composted poultry litter

USDA-ARS?s Scientific Manuscript database

Regions with long-term animal manure applications based upon nitrogen (N) requirements have concerns for elevated nutrient levels. Most attention has focused on phosphorus (P), but concern of heavy metal accumulation has received attention due to perceived environmental concerns. Some nutrient-dense...

Organochlorines and heavy metals in 17-year cicadas pose no apparent dietary threat to birds

USGS Publications Warehouse

Clark, D.R.

1992-01-01

Organochlorine and heavy metal concentrations in 17-year cicadas from Prince Georges and Anne Arundel Counties, Maryland, were well below levels known to be harmful to birds. Cicadas contained concentrations of metals similar to or less than other local invertebrates except they contained more copper than did earthworms. Copper and lead concentrations in cicadas from one site may have been elevated by sewage plant effluent deposited during river floodings. Cicadas from the median of a major highway did not contain more lead than cicadas from non-traffic sites.

Regulation of extracellular copper-binding proteins in copper-resistant and copper-sensitive mutants of Vibrio alginolyticus.

PubMed Central

Harwood, V J; Gordon, A S

1994-01-01

Extracellular proteins of wild-type Vibrio alginolyticus were compared with those of copper-resistant and copper-sensitive mutants. One copper-resistant mutant (Cu40B3) constitutively produced an extracellular protein with the same apparent molecular mass (21 kDa) and chromatographic behavior as copper-binding protein (CuBP), a copper-induced supernatant protein which has been implicated in copper detoxification in wild-type V. alginolyticus. Copper-sensitive V. alginolyticus mutants displayed a range of alterations in supernatant protein profiles. CuBP was not detected in supernatants of one copper-sensitive mutant after cultures had been stressed with 50 microM copper. Increased resistance to copper was not induced by preincubation with subinhibitory levels of copper in the wild type or in the copper-resistant mutant Cu40B3. Copper-resistant mutants maintained the ability to grow on copper-amended agar after 10 or more subcultures on nonselective agar, demonstrating the stability of the phenotype. A derivative of Cu40B3 with wild-type sensitivity to copper which no longer constitutively expressed CuBP was isolated. The simultaneous loss of both constitutive CuBP production and copper resistance in Cu40B3 indicates that constitutive CuBP production is necessary for copper resistance in this mutant. These data support the hypothesis that the extracellular, ca. 20-kDa protein(s) of V. alginolyticus is an important factor in survival and growth of the organism at elevated copper concentrations. The range of phenotypes observed in copper-resistant and copper-sensitive V. alginolyticus indicate that altered sensitivity to copper was mediated by a variety of physiological changes. Images PMID:8031076

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarwar, Tarique; Zafaryab, Md; Husain, Mohammed Amir

Ferulic acid (FA) is a plant polyphenol showing diverse therapeutic effects against cancer, diabetes, cardiovascular and neurodegenerative diseases. FA is a known antioxidant at lower concentrations, however at higher concentrations or in the presence of metal ions such as copper, it may act as a pro-oxidant. It has been reported that copper levels are significantly raised in different malignancies. Cancer cells are under increased oxidative stress as compared to normal cells. Certain therapeutic substances like polyphenols can further increase this oxidative stress and kill cancer cells without affecting the proliferation of normal cells. Through various in vitro experiments we havemore » shown that the pro-oxidant properties of FA are enhanced in the presence of copper. Comet assay demonstrated the ability of FA to cause oxidative DNA breakage in human peripheral lymphocytes which was ameliorated by specific copper-chelating agent such as neocuproine and scavengers of ROS. This suggested the mobilization of endogenous copper in ROS generation and consequent DNA damage. These results were further validated through cytotoxicity experiments involving different cell lines. Thus, we conclude that such a pro-oxidant mechanism involving endogenous copper better explains the anticancer activities of FA. This would be an alternate non-enzymatic, and copper-mediated pathway for the cytotoxic activities of FA where it can selectively target cancer cells with elevated levels of copper and ROS. - Highlights: • Pro-oxidant properties of ferulic acid are enhanced in presence of copper. • Ferulic acid causes oxidative DNA damage in lymphocytes as observed by comet assay. • DNA damage was ameliorated by copper chelating agent neocuproine and ROS scavengers. • Endogenous copper is involved in ROS generation causing DNA damage. • Ferulic acid exerts cancer cell specific cytotoxicity as observed by MTT assay.« less

Copper speciation in the gill microenvironment of carp (Cyprinus carpio) at various levels of pH.

PubMed

Tao, Shu; Long, Aimin; Xu, Fuliu; Dawson, R W

2002-07-01

The fish gill microenvironment of Cyprinus carpio under stress of copper exposure was investigated. pH and other parameters including free copper activity, alkalinity, and inorganic and organic carbons in the surrounding water (inspired water) and in the gill microenvironment (expired water) were measured or calculated at various levels of pH and varying total copper concentrations. The chemical equilibrium calculation (from MINEQA2) and complexation modeling (mucus-copper) were coupled to calculate both species distribution. The results indicate that the pH in the fish gill microenvironment was different from that in the surrounding water with a balance point around 6.9. The secretion of both CO(2) and mucus was affected in both linear and nonlinear ways when the fish were exposed to elevated concentrations of copper. The complexation capacity of the gill mucus was characterized by a conditional stability constant (logk(Cu-mucus)) of 5.37 along with a complexation equivalent concentration (L(Cu-mucus)) of 0.96 mmol Cu/mg C. For both the fish microenvironment and the surrounding water, the dominant copper species shifted from Cu(2+) to CuCO(3)(0) and to Cu(OH)(2)(0) when the pH of the surrounding water changed from 6.12 to 8.11. The change in copper speciation in the gill microenvironment is smaller than that in the surrounding water due to the pH buffering capacity of the fish gills.

Clinically distinct presentations of copper deficiency myeloneuropathy and cytopenias in a patient using excessive zinc-containing denture adhesive.

PubMed

Cathcart, Sahara J; Sofronescu, Alina G

2017-08-01

While copper deficiency has long been known to cause cytopenias, copper deficiency myeloneuropathy is a more recently described entity. Here, we present the case of two clinically distinct presentations of acquired copper deficiency syndromes secondary to excessive use of zinc-containing denture adhesive over five years: myeloneuropathy and severe macrocytic anemia and neutropenia. Extensive laboratory testing and histologic evaluation of the liver and bone marrow, were necessary to rule out other disease processes and establish the diagnosis of copper deficiency. The initial presentation consisted of a myelopathy involving the posterior columns. Serum and urine copper were significantly decreased, and serum zinc was elevated. On second presentation (five years later), multiple hematological abnormalities were detected. Serum copper was again decreased, while serum zinc was elevated. Zinc overload is a preventable cause of copper deficiency syndromes. This rare entity presented herein highlights the importance of patient, as well as provider, education. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Public health assessment for petitioned Phelps Dodge Corp Douglas Reduction Works, Douglas, Cochise County, Arizona, Region 9. Cerclis No. AZD008397143. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The Phelps-Dodge site, a former copper-smelting operation just outside Douglas and possibly Agua Prieta, Sonora, Mexico. This site contributed to lead-contaminated surface soils in residential areas in Douglas. Exposure to the lead-contaminated soils may have contributed and/or caused elevated blood levels in children living in both Douglas, AZ and Agua Prieta, Sonora, Mexico. Past emissions from the smelter included arsenic, lead, sulfur dioxide, inhalable particulate matter, and other heavy metals. The levels detected by air monitoring were elevated above health guidelines.

High mortality rates occur in copper deficient rats exposed to a normally nonlethal endotoxin treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

DiSilvestro, R.; Joseph, E.; Yang, F.L.

Endotoxin hepatotoxicity is proposed to occur by processes which could be retarded by 3 copper enzymes: ceruloplasmin, Cu-Zn superoxide dismutase (SOD), and extracellular (EC) SOD. Weanling rats fed low copper for 40 days showed low activity levels of these enzymes, and a very high mortality rate 20 h after endotoxin injection. No rats fed adequate copper died from this treatment. In addition, serum transaminase activities, indicators of liver damage, were elevated by 3 h to a greater extent in the deficient rats than in the adequates. The high susceptibility to endotoxemia in the deficient rats was not associated with lowmore » hepatic glutathione, high liver malondialedhyde, nor restricted metallothionein induction 3 h after endotoxin injection. Endotoxin reduced serum EC SOD activities in adequate and deficient rats, but final values were lower in the latter. Studies on roles of specific copper enzymes in resistance to endotoxemia are currently underway.« less

Ultra-deep oxidation and exotic copper formation at the late pliocene boyongan and bayugo porphyry copper-gold deposits, surigao, philippines: Geology, mineralogy, paleoaltimetry, and their implications for Geologic, physiographic, and tectonic controls

USGS Publications Warehouse

Braxton, D.P.; Cooke, D.R.; Ignacio, A.M.; Rye, R.O.; Waters, P.J.

2009-01-01

The Boyongan and Bayugo porphyry copper-gold deposits are part of an emerging belt of intrusion-centered gold-rich deposits in the Surigao district of northeast Mindanao, Philippines. Exhumation and weathering of these Late Pliocene-age deposits has led to the development of the world's deepest known porphyry oxidation profile at Boyongan (600 m), and yet only a modest (30-70 m) oxidation profile at adjacent Bayugo. Debris flows, volcanic rocks, and fluviolacustrine sediments accumulating in the actively extending Mainit graben subsequently covered the deposits and preserved the supergene profiles. At Boyongan and Bayugo, there is a vertical transition from shallower supergene copper oxide minerals (malachite + azurite + cuprite) to deeper sulfide-stable assemblages (chalcocite ?? hypogene sulfides). This transition provides a time-integrated proxy for the position of the water table at the base of the saturated zone during supergene oxidation. Contours of the elevation of the paleopotentiometric surface based on this min- eralogical transition show that the thickest portions of the unsaturated zone coincided with a silt-sand matrix diatreme breccia complex at Boyongan. Within the breccia complex, the thickness of the unsaturated zone approached 600 in, whereas outside the breccia complex (e.g., at Bayugo), the thickness averaged 50 m. Contours of the paleopotentiometric surface suggest that during weathering, groundwater flowed into the breccia complex from the north, south, and east, and exited along a high permeability zone to the west. The high relief (>550 m) on the elevation of the paleopotentiometric surface is consistent with an environment of high topographic relief, and the outflow zone to the west of the breccia complex probably reflects proximity to a steep scarp intersecting the western breccia complex margin. Stable isotope paleoaltimetry has enabled estimation of the elevation of the land surface, which further constrains the physiographic setting during supergene oxidation. Isotopic measurements of oxygen in supergene kaolinite from Boyongan suggest that local paleometeoric water involved in weathering had a ??180 composition of approximately -5.7 per mil. At the latitude of the southern Philippines, this value corresponds to Pleistocene rain water condensing at elevations between 750 and 1,050 m above contemporary sea level, providing a maximum estimate for the surface elevation during weathering of the porphyry systems. Physiographic reconstuctions suggest that the deep oxidation profile at Boyongan formed in an environment of high topographic relief immediately east of a prominent (>550 m) escarpment. The high permeability contrast between the breccia complex and the surrounding wall rocks, coupled with the proximity of the breccia complex to the escarpment, led to a depressed groundwater table and a vertically extensive unsaturated zone in the immediate vicinity of Boyongan. This thick vadose zone and the low hypogene pyrite/copper sulfide ratios (0.6) at Boyongan promoted in situ oxidation of copper sulfides with only modest (<200 m) supergene remobilization of copper. In contrast, higher hypogene pyrite/chalcopyrite ratios (2.3) at Bayugo led to greater acid production during weathering and more complete leaching of copper above the base of oxidation. This process promoted significant (600 m) lateral dispersion of copper down the paleohydraulic gradient into the diatreme breccia comple, ultimately leading to the formation of an exotic copper deposit. ?? 2009 Society of Economices Geologists, Inc.

ELEMENTAL MERCURY IN COPPER, SILVER, AND GOLD ORES: AN UNEXPECTED CONTRIBUTION TO LAKE SUPERIOR SEDIMENTS WITH GLOBAL IMPLICATIONS

EPA Science Inventory

Mercury and copper inventories are low in central Lake Superior and increase markedly towards the Keweenaw Peninsula...where copper, mercury, and silver inventories are elevated and highly correlated. High copper, silver, and mercury inventories can be traced back to shoreline st...

The interplay between siderophore secretion and coupled iron and copper transport in the heterocyst-forming cyanobacterium Anabaena sp. PCC 7120.

PubMed

Nicolaisen, Kerstin; Hahn, Alexander; Valdebenito, Marianne; Moslavac, Suncana; Samborski, Anastazia; Maldener, Iris; Wilken, Corinna; Valladares, Ana; Flores, Enrique; Hantke, Klaus; Schleiff, Enrico

2010-11-01

Iron uptake is essential for Gram-negative bacteria including cyanobacteria. In cyanobacteria, however, the iron demand is higher than in proteobacteria due to the function of iron as a cofactor in photosynthesis and nitrogen fixation, but our understanding of iron uptake by cyanobacteria stands behind the knowledge in proteobacteria. Here, two genes involved in this process in the heterocyst-forming cyanobacterium Anabaena sp. PCC 7120 were identified. ORF all4025 encodes SchE, a putative cytoplasmic membrane-localized transporter involved in TolC-dependent siderophore secretion. Inactivation of schE resulted in an enhanced sensitivity to high metal concentrations and decreased secretion of hydroxamate-type siderophores. ORF all4026 encodes a predicted outer membrane-localized TonB-dependent iron transporter, IacT. Inactivation of iacT resulted in decreased sensitivity to elevated iron and copper levels. Expression of iacT from the artificial trc promoter (P(trc)) resulted in sensitization against tested metals. Further analysis showed that iron and copper effects are synergistic because a decreased supply of iron induced a significant decrease of copper levels in the iacT insertion mutant but an increase of those levels in the strain carrying P(trc)-iacT. Our results unravel a link between iron and copper homeostasis in Anabaena sp. PCC 7120. Copyright © 2010 Elsevier B.V. All rights reserved.

Surface-water/ground-water interaction of the Spokane River and the Spokane Valley/Rathdrum Prairie aquifer, Idaho and Washington

USGS Publications Warehouse

Caldwell, Rodney R.; Bowers, Craig L.

2003-01-01

Although trace-element concentrations sometimes exceeded aquatic-life criteria in the water of the Spokane River and were elevated above national median values in the bed sediment, trace-element concentrations of all river and ground-water samples were at levels less than U.S. Environmental Protection Agency drinking-water standards. The Spokane River appears to be a source of cadmium, copper, zinc, and possibly lead in the near-river ground water. Dissolved cadmium, copper, and lead concentrations generally were less than 1 microgram per liter (µg/L) in the river water and ground water. During water year 2001, dissolved zinc concentrations were similar in water from near-river wells (17-71 µg/L) and the river water (22-66 µg/L), but were less than detection levels in wells farther from the river. Arsenic, found to be elevated in ground water in parts of the aquifer, does not appear to have a river source. Although the river does influence the ground-water chemistry in proximity to the river, it does not appear to adversely affect the ground-water quality to a level of human-health concern.

Copper toxicity and bioaccumulation in Chinese cabbage (Brassica pekinensis Rupr.).

PubMed

Xiong, Zhi-Ting; Wang, Hai

2005-04-01

Copper is among the major heavy metal contaminants in the environment with various anthropogenic and natural sources. Human health risk from heavy metal bioaccumulation in vegetables has been a subject of growing concern in recent years. To investigate Cu phytotoxic effects and bioaccumulation in the popular vegetable Chinese cabbage (Brassica pekinensis Rupr) as well as the implications for human health due to Cu in the vegetable supply, seed germination and pot culture experiments with this vegetable were carried out. Six levels (0, 0.008, 0.031, 0.125, 0.5, and 2.0 mM/L) and 3 levels (0, 0.2, and 1.0 mM/kg) of Cu treatments were performed for the seed germination and pot culture experiments, respectively. The LC(50) of Cu for seed germination of Chinese cabbage was 0.348 mM/L. In the pot culture experiments, Cu treatments significantly increased electrolyte leakage and peroxidase activity of shoot tissues, demonstrating Cu phytotoxicity to the plants. On the other hand, Cu treatments significantly stimulated, instead of reduced, chlorophyll content. Cu treatments did not show a significant effect on shoot biomass. Compared to the control, Cu treatments significantly elevated the Cu content of the shoots-9.9, 42.5, and 119.0 mg/kg (DW) of Cu were detected in the 0, 0.2, and 1.0 mM/kg treatments, respectively. These results showed that although the plants accumulated an elevated copper content and suffered damage to some extent under Cu treatment, they looked healthy. It was suggested that Chinese cabbage with an elevated Cu content and without showing visible symptoms of damage possibly could cause a risk to human health from the transfer of the metal in food.

Chronic copper exposure causes spatial memory impairment, selective loss of hippocampal synaptic proteins, and activation of PKR/eIF2α pathway in mice.

PubMed

Ma, Quan; Ying, Ming; Sui, Xiaojing; Zhang, Huimin; Huang, Haiyan; Yang, Linqing; Huang, Xinfeng; Zhuang, Zhixiong; Liu, Jianjun; Yang, Xifei

2015-01-01

Copper is an essential element for human growth and development; however, excessive intake of copper could contribute to neurotoxicity. Here we show that chronic exposure to copper in drinking water impaired spatial memory with simultaneous selective loss of hippocampal pre-synaptic protein synapsin 1, and post-synaptic density protein (PSD)-93/95 in mice. Copper exposure was shown to elevate the levels of nitrotyrosine and 8-hydroxydeoxyguanosine (8-OHdG) in hippocampus, two markers of oxidative stress. Concurrently, we also found that copper exposure activated double stranded RNA-dependent protein kinase (PKR) as evidenced by increased ratio of phosphorylated PKR at Thr451 and total PKR and increased the phosphorylation of its downstream signaling molecule eukaryotic initiation factor 2α (eIF2α) at Ser51 in hippocampus. Consistent with activation of PKR/eIF2α signaling pathway which was shown to mediate synaptic deficit and cognitive impairment, the levels of activating transcription factor 4 (ATF-4), a downstream signaling molecule of eIF2α and a repressor of CREB-mediated gene expression, were significantly increased, while the activity of cAMP response elements binding protein (CREB) was inactivated as suggested by decreased phosphorylation of CREB at Ser133 by copper exposure. In addition, the expression of the pro-apoptotic target molecule C/EBP homology protein (CHOP) of ATF-4 was upregulated and hippocampal neuronal apoptosis was induced by copper exposure. Taken together, we propose that chronic copper exposure might cause spatial memory impairment, selective loss of synaptic proteins, and neuronal apoptosis through the mechanisms involving activation of PKR/eIF2α signaling pathway.

A norovirus outbreak triggered by copper intoxication on a coach trip from the Netherlands to Germany, April 2010.

PubMed

Hoefnagel, J; van de Weerdt, Dh; Schaefer, O; Koene, R

2012-03-01

We report an unusual outbreak of norovirus infection on a coach trip. Overall, 30 of 40 people (including drivers and crew) developed nausea, vomiting and/or diarrhoea, 11 of them on the first day of the trip. The incidence epidemic curve showed a first peak on Day 1 and a second on Day 4. Nine passengers were hospitalised with gastrointestinal symptoms. Norovirus was found in stool samples from two patients, but the infection could not explain the first peak in the epidemic curve only a few hours after departure. Interviews with the passengers and an inspection of the coach and its water supply implicated the water used for coffee and tea as the potential source. Microbiological investigations of the water were negative, but chemical analysis showed a toxic concentration of copper. Blood copper levels as well as renal and liver function were determined in 28 of the 32 passengers who had been exposed to the water. One passenger who did not have gastrointestinal symptoms had an elevated copper level of 25.9 μmol/L, without loss of liver or renal function. It is likely that the spread of norovirus was enhanced because of vomiting of one of the passengers due to copper intoxication.

Undergraduates in the lab: Analyzing metal and organic contaminants in oysters and sediments from southeastern North Carolina

NASA Astrophysics Data System (ADS)

Mead, R. N.; Kipp, L. E.; Liberatore, H.; Sherard, S.; Steagall, M.; Skrabal, S. A.

2016-02-01

A state-funded project to analyze a suite of metal and organic contaminants in oyster tissues and ambient sediments was carried out nearly exclusively by over 10 undergraduates at the University of North Carolina Wilmington. This study will present Concentrations of various trace metals (most notably arsenic, copper, mercury, and zinc) and organic contaminants (polycyclic aromatic hydrocarbons and the antibacterial, triclosan) have been determined in oyster tissues and adjacent sediments in New Hanover and Brunswick counties, southeastern North Carolina. Trace metals that exceeded national median levels at multiple sites in this study included arsenic, copper, and zinc. Elevated levels of arsenic (exceeding the national median and, often, the national 85th percentiles) in oyster tissues are characteristic of much of the southeastern United States; these elevations are attributed to high natural background levels in the underlying bedrock and sediments as well as historical contamination by arsenic-containing agricultural pesticides. Another metal of national concern is mercury; however, concentrations of this metal were mostly at the national median for oyster tissue. Polycyclic aromatic hydrocarbons (PAHs) barely exceeded or were near the national median at only 3 sites, 2 in Lockwood Folly estuary, Brunswick County and 1 at Bradley Creek, New Hanover County. Concentrations at the remaining sites were 4 to >10 times less than the national median. Triclosan, an antibacterial compound used in many consumer products, was found in oyster tissues and sediments at the 4 sites at which it was examined. Oyster tissues contained triclosan at levels 2 to 43 times as high as adjacent sediments, indicating its bioaccumulation potential. Levels of metals and PAHs in oyster tissues are consistently elevated near more urbanized areas but are unlikely to be at levels harmful for human consumption.

Effect of an acid mine drainage effluent on phytoplankton biomass and primary production at Britannia Beach, Howe Sound, British Columbia.

PubMed

Levings, C D; Varela, D E; Mehlenbacher, N M; Barry, K L; Piercey, G E; Guo, M; Harrison, P J

2005-12-01

We investigated the effect of acid mine drainage (AMD) from an abandoned copper mine at Britannia Beach (Howe Sound, BC, Canada) on primary productivity and chlorophyll a levels in the receiving waters of Howe Sound before, during, and after freshet from the Squamish River. Elevated concentrations of copper (integrated average through the water column >0.050 mgl(-1)) in nearshore waters indicated that under some conditions a small gyre near the mouth of Britannia Creek may have retained the AMD from Britannia Creek and from a 30-m deep water outfall close to shore. Regression and correlation analyses indicated that copper negatively affected primary productivity during April (pre-freshet) and November (post-freshet). Negative effects of copper on primary productivity were not supported statistically for July (freshet), possibly because of additional effects such as turbidity from the Squamish River. Depth-integrated average and surface chlorophyll a were correlated to copper concentrations in April. During this short study we demonstrated that copper concentrations from the AMD discharge can negatively affect both primary productivity and the standing stock of primary producers in Howe Sound.

Yeast and Mammalian Metallothioneins Functionally Substitute for Yeast Copper-Zinc Superoxide Dismutase

NASA Astrophysics Data System (ADS)

Tamai, Katherine T.; Gralla, Edith B.; Ellerby, Lisa M.; Valentine, Joan S.; Thiele, Dennis J.

1993-09-01

Copper-zinc superoxide dismutase catalyzes the disproportionation of superoxide anion to hydrogen peroxide and dioxygen and is thought to play an important role in protecting cells from oxygen toxicity. Saccharomyces cerevisiae strains lacking copper-zinc superoxide dismutase, which is encoded by the SOD1 gene, are sensitive to oxidative stress and exhibit a variety of growth defects including hypersensitivity to dioxygen and to superoxide-generating drugs such as paraquat. We have found that in addition to these known phenotypes, SOD1-deletion strains fail to grow on agar containing the respiratory carbon source lactate. We demonstrate here that expression of the yeast or monkey metallothionein proteins in the presence of copper suppresses the lactate growth defect and some other phenotypes associated with SOD1-deletion strains, indicating that copper metallothioneins substitute for copper-zinc superoxide dismutase in vivo to protect cells from oxygen toxicity. Consistent with these results, we show that yeast metallothionein mRNA levels are dramatically elevated under conditions of oxidative stress. Furthermore, in vitro assays demonstrate that yeast metallothionein, purified or from whole-cell extracts, exhibits copper-dependent antioxidant activity. Taken together, these data suggest that both yeast and mammalian metallothioneins may play a direct role in the cellular defense against oxidative stress by functioning as antioxidants.

Communication between the N and C Termini Is Required for Copper-stimulated Ser/Thr Phosphorylation of Cu(I)-ATPase (ATP7B)*

PubMed Central

Braiterman, Lelita T.; Gupta, Arnab; Chaerkady, Raghothama; Cole, Robert N.; Hubbard, Ann L.

2015-01-01

The Wilson disease protein ATP7B exhibits copper-dependent trafficking. In high copper, ATP7B exits the trans-Golgi network and moves to the apical domain of hepatocytes where it facilitates elimination of excess copper through the bile. Copper levels also affect ATP7B phosphorylation. ATP7B is basally phosphorylated in low copper and becomes more phosphorylated (“hyperphosphorylated”) in elevated copper. The functional significance of hyperphosphorylation remains unclear. We showed that hyperphosphorylation occurs even when ATP7B is restricted to the trans-Golgi network. We performed comprehensive phosphoproteomics of ATP7B in low versus high copper, which revealed that 24 Ser/Thr residues in ATP7B could be phosphorylated, and only four of these were copper-responsive. Most of the phosphorylated sites were found in the N- and C-terminal cytoplasmic domains. Using truncation and mutagenesis, we showed that inactivation or elimination of all six N-terminal metal binding domains did not block copper-dependent, reversible, apical trafficking but did block hyperphosphorylation in hepatic cells. We showed that nine of 15 Ser/Thr residues in the C-terminal domain were phosphorylated. Inactivation of 13 C-terminal phosphorylation sites reduced basal phosphorylation and eliminated hyperphosphorylation, suggesting that copper binding at the N terminus propagates to the ATP7B C-terminal region. C-terminal mutants with either inactivating or phosphomimetic substitutions showed little effect upon copper-stimulated trafficking, indicating that trafficking does not depend on phosphorylation at these sites. Thus, our studies revealed that copper-dependent conformational changes in the N-terminal region lead to hyperphosphorylation at C-terminal sites, which seem not to affect trafficking and may instead fine-tune copper sequestration. PMID:25666620

Systemic serum amyloid A as a biomarker for exposure to zinc and/or copper-containing metal fumes.

PubMed

Baumann, R; Gube, M; Markert, A; Davatgarbenam, S; Kossack, V; Gerhards, B; Kraus, T; Brand, P

2018-01-01

Zinc- and copper-containing welding fumes increase systemic C-reactive protein (CRP). The aim of this study was to investigate the performance of the biomarkers serum amyloid A (SAA) and soluble vascular cell adhesion molecule-1 (VCAM-1) in this regard. Fifteen male subjects were exposed under controlled conditions to welding fumes containing either zinc, or copper, or copper and zinc for 6 h. Plasma samples were collected before, 6 and 24 h after start of exposure and biomarkers therein were measured by electrochemiluminescent assay. For each exposure, systemic concentrations of systemic SAA, but not VCAM-1, increased significantly at 24 h after exposure start compared with baseline ("copper only": P=0.0005, "zinc only": P=0.027, "copper and zinc": P=0.001). SAA showed a wider range of concentrations than did CRP and its levels increased up to 19-fold after welding fume exposure. The recognition of copper as a potential harmful component in welding fumes, also independent from zinc, deserves further consideration. SAA might represent a new sensitive biomarker for potential subclinical sterile inflammation after inhalation of copper- and/or zinc-containing welding fumes. As elevations of CRP and SAA protein have both been linked to a higher risk for cardiovascular disease, these findings might particularly be important for long-term welders.

Proteome characterization of copper stress responses in the roots of sorghum

USDA-ARS?s Scientific Manuscript database

Copper (Cu) is an essential micronutrient for all living organisms, but at elevated concentrations, it is extremely toxic to plants and can inactivate and disturb protein structures. To explore the molecular changes involved in the copper stress response, a study was conducted using the roots of sor...

Copper-redox cycling by coumarin-di(2-picolyl)amine hybrid molecule leads to ROS-mediated DNA damage and apoptosis: A mechanism for cancer chemoprevention.

PubMed

Khan, Saman; Zafar, Atif; Naseem, Imrana

2018-06-25

Coumarin is an important bioactive pharmacophore. It is found in plants as a secondary metabolite and exhibits diverse pharmacological properties including anticancer effects against different malignancies. Therapeutic efficacy of coumarin derivatives depends on the pattern of substitution and conjugation with different moieties. Cancer cells contain elevated copper as compared to normal cells that plays a role in angiogenesis. Thus, targeting copper in malignant cells via copper chelators can serve as an attractive targeted anticancer strategy. Our previous efforts led to the synthesis of di(2-picolyl)amine-3(bromoacetyl)coumarin hybrid molecule (ligand-L) endowed with DNA/Cu(II) binding properties, and ROS generation ability in the presence of copper ions. In the present study, we aimed to validate copper-dependent cytotoxic action of ligand-L against malignant cells. For this, we used a cellular model system of copper (Cu) overloaded lymphocytes (CuOLs) to simulate malignancy-like condition. In CuOLs, lipid peroxidation/protein carbonylation, ROS generation, DNA fragmentation and apoptosis were investigated in the presence of ligand-L. Results showed that ligand-L-Cu(II) interaction leads to ROS generation, lipid peroxidation/protein carbonylation (oxidative stress parameters), DNA damage, up-regulation of p53 and mitochondrial-mediated apoptosis in treated lymphocytes. Further, pre-incubation with neocuproine (membrane permeable copper chelator) and ROS scavengers attenuated the DNA damage and apoptosis. These results suggest that cellular copper acts as molecular target for ligand-L to propagate redox cycling and generation of ROS via Fenton-like reaction leading to DNA damage and apoptosis. Further, we showed that ligand-L targets elevated copper in breast cancer MCF-7 and colon cancer HCT116 cells leading to a pro-oxidant inhibition of proliferation of cancer cells. In conclusion, we propose copper-dependent ROS-mediated mechanism for the cytotoxic action of ligand-L in malignant cells. Thus, targeting elevated copper represents an effective therapeutic strategy for selective cytotoxicity against malignant cells. Copyright © 2018 Elsevier B.V. All rights reserved.

Four-year follow-up of a Wilson disease pedigree complicated with epilepsy and hypopituitarism: Case report with a literature review.

PubMed

Zhang, Qi-Jie; Xu, Liu-Qing; Wang, Chong; Hu, Wei; Wang, Ning; Chen, Wan-Jin

2016-12-01

Wilson's disease (WD) is an autosomal recessive inherited disorder of copper metabolism with excellent prognosis if treated timely. However, WD is usually prone to neglect and misdiagnosis at an early stage. We reported a rare WD pedigree, and the clinical features, laboratory tests, and gene mutations were analyzed in detail. The patient was a 17-year-old and 136-cm-tall girl who presented with limb weakness, combined with multi-organ disorders including blind eye, epilepsy, and hypopituitarism. Clinical tests showed a low serum ceruloplasmin level, high urinary copper excretion and Kayser-Fleischer (K-F) rings. She carried a compound heterozygous mutations in ATP7B gene (c.2828G>A and c.3884C>T). Her younger brother, as an asymptomatic patient, manifested with elevation of transaminases but without neurological and hepatic symptoms. They were diagnosed as WD finally. They were treated with sodium dimercaptosulphonate, supplemented with zinc gluconate, vitamin B6, vitamin C, as well as restriction of dietary copper. The urinary copper excretion and serum transaminase level decreased gradually. The abnormal signals in brainstem and basal ganglia were also remarkably decreased after 4-year of de-copper treatment. As to the patients with complicated clinical manifestations, the extrapyramidal symptom and basal ganglia signals should be concerned. The serum ceruloplasmin detection and ATP7B gene mutation screening are necessary.

Bulk Nanocrystalline Metals: Review of the Current State of the Art and Future Opportunities for Copper and Copper Alloys

DTIC Science & Technology

2014-05-13

nanocrystalline materials using mechanical alloying, the alloy development and synthesis process for stabilizing these materials at elevated temperatures, and...the physical and mechanical properties of nanocrystalline materials with a focus throughout on nanocrystalline copper and a nanocrystalline Cu-Ta...approaches as well as experimental results for grain growth, grain boundary processes, and deformation mechanisms in nanocrystalline copper are

Elevated copper impairs hepatic nuclear receptor function in Wilson's disease

USDA-ARS?s Scientific Manuscript database

Wilson's disease (WD) is an autosomal recessive disorder that results in accumulation of copper in the liver as a consequence of mutations in the gene encoding the copper-transporting P-type ATPase (ATP7B). WD is a chronic liver disorder, and individuals with the disease present with a variety of co...

Leaf proteome characterization in the context of physiological and morphological changes in response to copper stress in sorghum

USDA-ARS?s Scientific Manuscript database

Copper (Cu) is an essential micronutrient required for the growth and development of plants. However, at elevated concentrations in soil, copper is very toxic to plant cells due to its inhibitory effects against many physiological and biochemical processes. In spite of its potential physiological an...

An investigation of roof runoff during rain events at the Royal Military College of Canada and potential discharge to Lake Ontario.

PubMed

Kelly, David G; Weir, Ron D; White, Steven D

2011-01-01

The Royal Military College of Canada, located on the north eastern shore of Lake Ontario, possesses an abundance of copper roofs and lacks surface water treatment prior to discharge into Lake Ontario. Rainwater, roof runoff and soil samples were collected and analyzed for copper and other parameters. Copper was consistently detected in runoff samples with average concentrations of 3200 +/- 2100 microg/L. Multivariable linear regression analysis for a dependant copper runoff concentration yielded an adjusted R2 value of 0.611, based on an independent variable model using minimum temperature, maximum temperature, total precipitation, and wind speed. Lake water samples taken in the vicinity of storm water outfalls draining areas with copper roofs ranged from 2.0 to 40 microg/L copper. Such data exceed the 2.0 microg/L Canadian Water Quality Guidelines for the Protection of Aquatic Life as outlined by the Canadian Council of Ministers of the Environment (CCME). Analysis of raw, filtered and digested forms suggested that the majority of copper present in runoff and lake water samples was in a dissolved form. The majority of soils taken in this study displayed copper concentrations below the 63 microg/g CCME residential/parkland land use limits. These findings suggested that ion exchange processes between runoff water and soil do not occur to a sufficient extent to elevate copper levels in soil. It may therefore be concluded that the eventual fate of copper, which is not discharged via storm water outfalls, is lost to the water table and Lake Ontario through the sub-soil.

Concentration of heavy metals in drinking water of different localities in district east Karachi.

PubMed

Jaleel, M A; Noreen, R; Baseer, A

2001-01-01

Several heavy metals are present in drinking water that play important roles in the body provided their level remains within the specified range recommended by WHO. But now due to the industrialization and rapid urbanization, the problems of pollution have surfaced. This study was designed to ascertain the contents of some heavy metals and then their variations if any in drinking water in different localities of district East of Karachi, Pakistan. Drinking water samples were collected from different sources and localities of district East of Karachi. The concentration of the heavy metals i.e. Lead, Arsenic, Copper, Iron, Mercury, Chromium, Manganese, Nickel, Cadmium and Zinc were determined by Atomic Absorption Spectrophotometry. PH was estimated by pH meter. Total dissolved solids (TDS) were calculated by formula. These concentrations of heavy metals, pH and TDS were compared with the standards set by WHO. Concentrations of lead and nickel were found to be significantly elevated as compared to WHO recommended levels in all the three sources of water (Piped water, Hand pump water and Tanker water supply). Chromium was found to be raised in hand pump water. Arsenic and Mercury were not detected in any source of water. Copper, iron, manganese, cadmium and zinc were found to be within the safe limits in all the three sources of water. pH was found to be within the range of WHO recommended level in all the three sources of water. TDS was found to be elevated in hand pump water and tanker water. Concentrations of lead and nickel were found to be significantly elevated as compared to WHO recommended levels in all the three sources of water in district East of Karachi.

Cancer cell-selective killing polymer/copper combination.

PubMed

He, Huacheng; Altomare, Diego; Ozer, Ufuk; Xu, Hanwen; Creek, Kim; Chen, Hexin; Xu, Peisheng

2016-01-01

Chemotherapy has been adopted for cancer treatment for decades. However, its efficacy and safety are frequently compromised by the multidrug-resistance of cancer cells and the poor cancer cell selectivity of anticancer drugs. Hereby, we report a combination of a pyridine-2-thiol containing polymer and copper which can effectively kill a wide spectrum of cancer cells, including drug resistant cancer cells, while sparing normal cells. The polymer nanoparticle enters cells via an exofacial thiol facilitated route, and releases active pyridine-2-thiol with the help of intracellularly elevated glutathione (GSH). Due to their high GSH level, cancer cells are more vulnerable to the polymer/copper combination. In addition, RNA microarray analysis revealed that the treatment can reverse cancer cells' upregulated oncogenes (CIRBP and STMN1) and downregulated tumor suppressor genes (CDKN1C and GADD45B) to further enhance the selectivity for cancer cells.

Flavonoids-induced redox cycling of copper ions leads to generation of reactive oxygen species: A potential role in cancer chemoprevention.

PubMed

Arif, Hussain; Sohail, Aamir; Farhan, Mohd; Rehman, Ahmed Abdur; Ahmad, Aamir; Hadi, S M

2018-01-01

Flavonoids, a class of polyphenols are known to be effective inducers of apoptosis and cytotoxicity in cancer cells. It is believed that antioxidant activity of polyphenols cannot fully account for induction of apoptosis and chemotherapeutic prevention in various cancers. In this article, by employing single cell alkaline gel electrophoresis (comet assay), we established that antioxidants, flavonoids such as (myricetin=MN, fisetin=FN, quercetin=QN, kaempferol=KL and galangin=GN) can cause cellular DNA breakage, also act as pro-oxidant in presence of transition metal ion such as copper. It was observed that the extent of cellular DNA breakage was found significantly higher in presence of copper. Hydroxyl radicals are generated as a sign of flavonoids' pro-oxidant nature through redox recycling of copper ions. Further, a dose-dependent inhibition of proliferation of breast cancer cells MDA-MB-231 by MN was found leading to pro-oxidant cell death, as assessed by MTT assay. Since levels of copper are considerably elevated in tissue, cell and serum during various malignancies, suggesting that cancer cells would be more subject to copper induced oxidative DNA breakage. Such a copper dependent pro-oxidant cytotoxic mechanism better explains the anticancer activity and preferential cytotoxicity of dietary phytochemicals against cancer cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluating the role of ion composition on the toxicity of copper to Ceriodaphnia dubia in very hard waters.

PubMed

Gensemer, Robert W; Naddy, Rami B; Stubblefield, William A; Hockett, J Russell; Santore, Robert; Paquin, Paul

2002-09-01

The mitigating effect of increasing hardness on metal toxicity is reflected in water quality criteria in the United States over the range of 25-400 mgl(-1) (as CaCO(3)). However, waters in the arid west of the US frequently exceed 400 mgl(-1) hardness, and the applicability of hardness-toxicity relationships in these waters is unknown. Acute toxicity tests with Ceriodaphnia dubia were conducted at hardness levels ranging from approximately 300 to 1,200 mgl(-1) using reconstituted waters that mimic two natural waters with elevated hardness: (1) alkaline desert southwest streams (Las Vegas Wash, NV), and (2) low alkalinity waters from a CaSO(4)-treated mining effluent in Colorado. The moderately-alkaline EPA synthetic hard water was also included for comparison. Copper toxicity did not consistently vary as a function of hardness, but likely as a function of other water quality characteristics (e.g., alkalinity or other correlated factors). The hardness equations used in regulatory criteria, therefore, may not provide an accurate level of protection against copper toxicity in all types of very hard waters. However, the mechanistic Biotic ligand model generally predicted copper toxicity within +/-2X of observed EC(50) values, and thus may be more useful than hardness for modifying water quality criteria.

Thermal behavior of copper processed by ECAP at elevated temperatures

NASA Astrophysics Data System (ADS)

Gonda, Viktor

2018-05-01

Large amount of strengthening can be achieved by equal channel angular pressing (ECAP), by the applied severe plastic deformation during the processing. For pure metals, this high strength is accompanied with low thermal stability due to the large activation energy for recrystallization. In the present paper, the chosen technological route was elevated temperature single pass ECAP processing of copper, and its effect on the thermal behavior during the restoration processes of the deformed samples was studied.

Serum micronutrient levels, nucleic acid metabolism and antioxidant defences in pregnant Nigerians: implications for fetal and maternal health.

PubMed

Anetor, J I; Adelaja, O; Adekunle, A O

2003-09-01

Micronutrients regulate numerous metabolic processes in pregnancy but their possible antioxidant function and contributions of alterations in their metabolism to fetal and maternal morbidity and mortality have received insufficients attention. Serum levels of copper, manganese and zinc were determined in 40 pregnant Nigerian women spread across the three trimesters of pregnancy and compared with those of 25 non-pregnant women of similar demographic and anthropometric characteristics. Serum levels of uric acid were also determined in both groups of women. The mean serum levels of manganese and zinc were significantly lower in the pregnant than in the non-pregnant state (P<0.02, P<0.002), respectively. Unlike manganese and zinc, copper was significantly elevated in the pregnant than in the non-pregnant state. The endogenous anti-oxidant, uric acid, was also significantly reduced in the pregnant than in the non-pregnant state (P<0.001). Copper levels increased progressively in all the three trimesters of pregnancy compared with controls (P<0.001). However, zinc levels declined steadily in all the 3 trimesters, but only the level of the third trimester was significantly different from the non-pregnant state (P<0.05). Unlike zinc, uric acid rose consistently in all the 3 trimesters compared with the non-pregnant state. Manganese and uric acid were significantly more elevated in the third than the first trimester. One way analysis of variance (ANOVA) and multiple comparisons (Tukey HSD) show that the differences in the antioxidant levels can be ascribed mainly to the second and third trimesters. The prevalence of zinc deficiency was 4.0% in the non-pregnant state as compared to 22.5% in the pregnant subjects. The implications of micronutrient deficiencies and associated antioxidant status in pregnancy are discussed. Considering their role in pregnancy, prevention of such deficiencies and attendant oxidative stress may contribute to a reduction in the incidence of fetal and maternal ill-health, and complications of pregnancy. Interventions should be aimed mainly at the second and third trimesters.

Copper toxicity in Chinese cabbage is not influenced by plant sulphur status, but affects sulphur metabolism-related gene expression and the suggested regulatory metabolites.

PubMed

Shahbaz, M; Stuiver, C E E; Posthumus, F S; Parmar, S; Hawkesford, M J; De Kok, L J

2014-01-01

The toxicity of high copper (Cu) concentrations in the root environment of Chinese cabbage (Brassica pekinensis) was little influenced by the sulphur nutritional status of the plant. However, Cu toxicity removed the correlation between sulphur metabolism-related gene expression and the suggested regulatory metabolites. At high tissue Cu levels, there was no relation between sulphur metabolite levels viz. total sulphur, sulphate and water-soluble non-protein thiols, and the expression and activity of sulphate transporters and expression of APS reductase under sulphate-sufficient or-deprived conditions, in the presence or absence of H2 S. This indicated that the regulatory signal transduction pathway of sulphate transporters was overruled or by-passed upon exposure to elevated Cu concentrations. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

Catalytic therapy of cancer by ascorbic acid involves redox cycling of exogenous/endogenous copper ions and generation of reactive oxygen species.

PubMed

Hadi, S M; Ullah, M F; Shamim, U; Bhatt, S H; Azmi, A S

2010-01-01

Catalytic therapy is a cancer treatment modality based on the generation of reactive oxygen species (ROS) through administration of ascorbate/medicinal herbal extracts and copper. It is known that antioxidants such as ascorbate also exhibit prooxidant activity in the presence of transition metals such as copper. Based on our work and that in the literature, in this review we propose a mechanism for the cytotoxic action of ascorbate against cancer cells. It involves redox cycling of exogenous/endogenous copper ions and the consequent generation of ROS leading to oxidative DNA breakage. Using human peripheral lymphocytes and the Comet assay, we have shown that ascorbic acid is able to cause oxidative breakage in cellular DNA. Such DNA degradation is inhibited by neocuproine (a Cu(I) sequestering agent) and scavengers of ROS indicating that the cellular DNA breakage involves the generation of Cu(I) and formation of ROS. Similar results are also obtained with plant polyphenol antioxidants that are important constituents of medicinal herbal extracts. Copper is an essential component of chromatin and can take part in redox reactions. It is well established that tissue, cellular and serum copper levels are considerably elevated in various malignancies. Therefore, cancer cells may be more subject to electron transfer between copper ions and ascorbate/plant polyphenols to generate ROS. In this review we cite evidence to indicate that in catalytic therapy cytotoxic action against cancer cells involves redox cycling of exogenous/endogenous copper ions. Copyright © 2010 S. Karger AG, Basel.

Different roles of glutathione in copper and zinc chelation in Brassica napus roots.

PubMed

Zlobin, Ilya E; Kartashov, Alexander V; Shpakovski, George V

2017-09-01

We investigated the specific features of copper and zinc excess action on the roots of canola (Brassica napus L.) plants. Copper rapidly accumulated in canola root cells and reached saturation during several hours of treatment, whereas the root zinc content increased relatively slowly. Excessive copper and zinc entry inside the cell resulted in significant cell damage, as evidenced by alterations in plasmalemma permeability and decreases in cellular enzymatic activity. Zinc excess specifically damaged root hair cells, which correlated with a pronounced elevation of their labile zinc level. In vitro, we showed that reduced glutathione (GSH) readily reacted with copper ions to form complexes with blocked sulfhydryl groups. In contrast, zinc ions were ineffective as glutathione blockers, and glutathione molecules did not lose their specific chemical activity in the presence of Zn 2+ ions. The effect of copper and zinc excess on the glutathione pool in canola root cells was analysed by a combination of biochemical determination of total and oxidized glutathione contents and fluorescent staining of free reduced glutathione with monochlorobimane dye. Excess copper led to dose-dependent diminution of free reduced glutathione contents in the root cells, which could not be explained by the loss of total cellular glutathione or its oxidation. In contrast, we observed little effect of much higher intracellular zinc concentrations on the free reduced glutathione content. We concluded that GSH plays an important role in copper excess, but not zinc excess chelation, in canola root cells. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Role of Trace Elements for Oxidative Status and Quality of Human Sperm.

PubMed

Nenkova, Galina; Petrov, Lubomir; Alexandrova, Albena

2017-08-04

Oxidative stress affects sperm quality negatively. To maintain the pro/antioxidant balance, some metal ions (e.g. copper, zink, iron, selenium), which are co-factors of the antioxidant enzymes, are essential. However, iron and copper could act as prooxidants inducing oxidative damage of spermatozoa. To reveal a possible correlation between the concentrations of some metal ions (iron, copper, zinc, and selenium) in human seminal plasma, oxidative stress, assessed by malondialdehyde and total glutathione levels, and semen quality, assessed by the parameters count, motility, and morphology. Descriptive study. The semen analysis for volume, count, and motility was performed according to World Health Organization (2010) guidelines, using computer-assisted semen analysis. For the determination of spermatozoa morphology, a SpermBlue staining method was applied. Depending on their parameters, the sperm samples were categorized into normozoospermic, teratozoospermic, asthenoteratozoospermic, and oligoteratozoospermic. The seminal plasma content of iron, copper, zinc, and selenium was estimated by atomic absorption spectroscopy. The malondialdehyde and total glutathione levels were quantified spectrophotometrically. In the groups with poor sperm quality, the levels of Fe were higher, whereas those of Zn and Se were significantly lower than in the normozoospermic group. In all groups with poor sperm quality, increased levels of malondialdehyde and decreased glutathione levels were detected as evidence of oxidative stress occurrence. All these differences are most pronounced in the asthenoteratozoospermic group where values differ nearly twice as much compared to the normozoospermic group. The Fe concentration correlated positively with the malondialdehyde (r=0.666, p=0.018), whereas it showed a negative correlation with the level of total glutathione (r=-0.689, p=0.013). The total glutathione level correlated positively with the sperm motility (r=0.589, p=0.044). The elevated levels of Fe and the reduced Se levels are associated with sperm damage. The changes in the concentrations of the trace elements in human seminal plasma may be related to sperm quality since they are involved in the maintenance of the pro-/antioxidative balance in ejaculate.

Copper Capture in a Thioether-Functionalized Porous Polymer Applied to the Detection of Wilson’s Disease

PubMed Central

2016-01-01

Copper is an essential nutrient for life, but at the same time, hyperaccumulation of this redox-active metal in biological fluids and tissues is a hallmark of pathologies such as Wilson’s and Menkes diseases, various neurodegenerative diseases, and toxic environmental exposure. Diseases characterized by copper hyperaccumulation are currently challenging to identify due to costly diagnostic tools that involve extensive technical workup. Motivated to create simple yet highly selective and sensitive diagnostic tools, we have initiated a program to develop new materials that can enable monitoring of copper levels in biological fluid samples without complex and expensive instrumentation. Herein, we report the design, synthesis, and properties of PAF-1-SMe, a robust three-dimensional porous aromatic framework (PAF) densely functionalized with thioether groups for selective capture and concentration of copper from biofluids as well as aqueous samples. PAF-1-SMe exhibits a high selectivity for copper over other biologically relevant metals, with a saturation capacity reaching over 600 mg/g. Moreover, the combination of PAF-1-SMe as a material for capture and concentration of copper from biological samples with 8-hydroxyquinoline as a colorimetric indicator affords a method for identifying aberrant elevations of copper in urine samples from mice with Wilson’s disease and also tracing exogenously added copper in serum. This divide-and-conquer sensing strategy, where functional and robust porous materials serve as molecular recognition elements that can be used to capture and concentrate analytes in conjunction with molecular indicators for signal readouts, establishes a valuable starting point for the use of porous polymeric materials in noninvasive diagnostic applications. PMID:27285482

Copper modified carbon molecular sieves for selective oxygen removal

NASA Technical Reports Server (NTRS)

Sharma, Pramod K. (Inventor); Seshan, Panchalam K. (Inventor)

1992-01-01

Carbon molecular sieves modified by the incorporation of finely divided elemental copper useful for the selective sorption of oxygen at elevated temperatures. The carbon molecular sieves can be regenerated by reduction with hydrogen. The copper modified carbon molecular sieves are prepared by pyrolysis of a mixture of a copper-containing material and polyfunctional alcohol to form a sorbent precursor. The sorbent precursors are then heated and reduced to produce copper modified carbon molecular sieves. The copper modified carbon molecular sieves are useful for sorption of all concentrations of oxygen at temperatures up to about 200.degree. C. They are also useful for removal of trace amount of oxygen from gases at temperatures up to about 600.degree. C.

VAPOR PHASE MERCURY SORPTION BY ORGANIC SULFIDE MODIFIED BIMETALLIC IRON-COPPER NANOPARTICLE AGGREGATES

EPA Science Inventory

Novel organic sulfide modified bimetallic iron-copper nanoparticle aggregate sorbent materials have been synthesized for removing elemental mercury from vapor streams at elevated temperatures (120-140 °C). Silane based (disulfide silane and tetrasulfide silane) and alkyl sulfide ...

Safety of long-term restrictive diets for peroxisomal disorders: vitamin and trace element status of patients treated for Adult Refsum Disease.

PubMed

Baldwin, E J; Harrington, D J; Sampson, B; Feher, M D; Wierzbicki, A S

2016-03-01

Adult Refsum's Disease (ARD) is caused by defects in the pathway for alpha-oxidation of phytanic acid (PA). Treatment involves restricting the dietary intake of phytanic acid by reducing the intake of dairy-derived fat. The adequacy of micronutrient intake in patients with ARD is unknown. Patients established on the Chelsea low-PA diet had general diet macronutrients, vitamins and trace elements assessed using 7-day-weighed intakes and serial 24-h recalls. Intakes were compared with biochemical assessments of nutritional status for haematinics (ferritin), trace elements (copper, zinc, iron, selenium), water- (vitamin B6 , B12 and folate) and fat-soluble vitamins (A, D, E and K). Eleven subjects (four women, seven men) were studied. Body mass index was 27 ± 5 kg/m(2) (range 19-38). All subjects had high sodium intakes (range 1873-4828 mg). Fat-soluble vitamin insufficiencies occurred in some individuals (vitamin A, n = 2; vitamin D, n = 6; vitamin E, n = 3; vitamin K, n = 10) but were not coincident. Vitamin B6 levels were normal or elevated (n = 6). Folate and 5-methyltetrahydrofolate concentrations were normal. Metabolic vitamin B12 insufficiency was suspected in four subjects based on elevated methylmalonic acid concentrations. Low copper and selenium intakes were noted in some subjects (n = 7, n = 2) but plasma levels were adequate. Iron, ferritin and zinc intakes and concentrations were normal. Subjects with ARD can be safely managed on the Chelsea low PA without routine micronutrient supplementation. Sodium intake should be monitored and reduced. Periodic nutritional screening may be necessary for fat-soluble vitamins, vitamin B12 , copper or selenium. © 2016 John Wiley & Sons Ltd.

Effect of thiomolybdate and ammonium molybdate in pregnant guinea pigs and their offspring.

PubMed

Howell, J M; Shunxiang, Y; Gawthorne, J M

1993-09-01

Groups of eight guinea pigs and their offspring were given drinking water containing molybdenum as ammonium molybdate (AM) or thiomolybdate (TM) throughout and subsequent to pregnancy. All adult females had oestrous cycles and conception rates were unaffected. Fetal death was common in groups given the high dose of TM. The concentration of copper in liver was reduced in all groups at all ages except for pups killed at birth from animals given AM. The concentration of molybdenum was elevated in liver and kidney of all groups and was statistically significant in the majority. The concentration in plasma of copper, molybdenum and copper insoluble in trichloroacetic acid was elevated in all groups. Superoxide dismutase activity was significantly reduced in dams and six-week-old pups in which TM administration commenced before mating. Histological damage occurred in the pancreas of animals given AM or TM. The effects on the fetus and pancreas were considered to result from copper deficiency rather than molybdenum toxicity.

Neuronal differentiation is associated with a redox-regulated increase of copper flow to the secretory pathway

PubMed Central

Hatori, Yuta; Yan, Ye; Schmidt, Katharina; Furukawa, Eri; Hasan, Nesrin M.; Yang, Nan; Liu, Chin-Nung; Sockanathan, Shanthini; Lutsenko, Svetlana

2016-01-01

Brain development requires a fine-tuned copper homoeostasis. Copper deficiency or excess results in severe neuro-pathologies. We demonstrate that upon neuronal differentiation, cellular demand for copper increases, especially within the secretory pathway. Copper flow to this compartment is facilitated through transcriptional and metabolic regulation. Quantitative real-time imaging revealed a gradual change in the oxidation state of cytosolic glutathione upon neuronal differentiation. Transition from a broad range of redox states to a uniformly reducing cytosol facilitates reduction of the copper chaperone Atox1, liberating its metal-binding site. Concomitantly, expression of Atox1 and its partner, a copper transporter ATP7A, is upregulated. These events produce a higher flux of copper through the secretory pathway that balances copper in the cytosol and increases supply of the cofactor to copper-dependent enzymes, expression of which is elevated in differentiated neurons. Direct link between glutathione oxidation and copper compartmentalization allows for rapid metabolic adjustments essential for normal neuronal function. PMID:26879543

Neuronal differentiation is associated with a redox-regulated increase of copper flow to the secretory pathway.

PubMed

Hatori, Yuta; Yan, Ye; Schmidt, Katharina; Furukawa, Eri; Hasan, Nesrin M; Yang, Nan; Liu, Chin-Nung; Sockanathan, Shanthini; Lutsenko, Svetlana

2016-02-16

Brain development requires a fine-tuned copper homoeostasis. Copper deficiency or excess results in severe neuro-pathologies. We demonstrate that upon neuronal differentiation, cellular demand for copper increases, especially within the secretory pathway. Copper flow to this compartment is facilitated through transcriptional and metabolic regulation. Quantitative real-time imaging revealed a gradual change in the oxidation state of cytosolic glutathione upon neuronal differentiation. Transition from a broad range of redox states to a uniformly reducing cytosol facilitates reduction of the copper chaperone Atox1, liberating its metal-binding site. Concomitantly, expression of Atox1 and its partner, a copper transporter ATP7A, is upregulated. These events produce a higher flux of copper through the secretory pathway that balances copper in the cytosol and increases supply of the cofactor to copper-dependent enzymes, expression of which is elevated in differentiated neurons. Direct link between glutathione oxidation and copper compartmentalization allows for rapid metabolic adjustments essential for normal neuronal function.

Microplastic Deformation of Submicrocrystalline Copper at Room and Elevated Temperatures

NASA Astrophysics Data System (ADS)

Dudarev, E. F.; Pochivalova, G. P.; Tabachenko, A. N.; Maletkina, T. Yu.; Skosyrskii, A. B.; Osipov, D. A.

2017-02-01

of investigations of submicrocrystalline copper subjected to cold rolling after abc pressing by methods of backscatter electron diffraction and x-ray diffraction analysis are presented. It is demonstrated that after such combined intensive plastic deformation, the submicrocrystalline structure with average grain-subgrain structure elements having sizes of 0.63 μm is formed with relative fraction of high-angle grain boundaries of 70% with texture typical for rolled copper. Results of investigation of microplastic deformation of copper with such structure at temperatures in the interval 295-473 K and with submicrocrystalline structure formed by cold rolling of coarse-grained copper are presented.

The prooxidant action of dietary antioxidants leading to cellular DNA breakage and anticancer effects: implications for chemotherapeutic action against cancer.

PubMed

Ullah, M F; Ahmad, Aamir; Khan, Husain Y; Zubair, H; Sarkar, Fazlul H; Hadi, S M

2013-11-01

Plant-derived dietary antioxidants have attracted considerable interest in recent past for their ability to induce apoptosis and regression of tumors in animal models. While it is believed that the antioxidant properties of these agents may contribute to lowering the risk of cancer induction by impeding oxidative injury to DNA, it could not account for apoptosis induction and chemotherapeutic observations. In this article, we show that dietary antioxidants can alternatively switch to a prooxidant action in the presence of transition metals such as copper. Such a prooxidant action leads to strand breaks in cellular DNA and growth inhibition in cancer cells. Further, the cellular DNA breakage and anticancer effects were found to be significantly enhanced in the presence of copper ions. Moreover, inhibition of antioxidant-induced DNA strand breaks and oxidative stress by Cu(I)-specific chelators bathocuproine and neocuproine demonstrated the role of endogenous copper in the induction of the prooxidant mechanism. Since it is well established that tissue, cellular, and serum copper levels are considerably elevated in various malignancies, such a prooxidant cytotoxic mechanism better explains the anticancer activity of dietary antioxidants against cancer cells.

Copper crystallite in carbon molecular sieves for selective oxygen removal

NASA Technical Reports Server (NTRS)

Sharma, Pramod K. (Inventor); Seshan, Panchalam K. (Inventor)

1993-01-01

Carbon molecular sieves modified by the incorporation of finely divided elemental copper useful for the selective sorption of oxygen at elevated temperatures. The carbon molecular sieves can be regenerated by reduction with hydrogen. The copper modified carbon molecular sieves are prepared by pyrolysis of a mixture of a copper-containing material and polyfurfuryl alcohol to form a sorbent precursor. The sorbent precursors are then heated and reduced to produce copper modified carbon molecular sieves. The copper modified carbon molecular sieves are useful for sorption of all concentrations of oxygen at temperatures up to about 200.degree. C. They are also useful for removal of trace amount of oxygen from gases at temperatures up to about 600.degree. C.

Glutamic acid leaching of synthetic covellite - A model system combining experimental data and geochemical modeling.

PubMed

Barthen, R; Karimzadeh, L; Gründig, M; Grenzer, J; Lippold, H; Franke, K; Lippmann-Pipke, J

2018-04-01

For Kupferschiefer mining established pyrometallurgical and acidic bioleaching methods face numerous problems. This is due to the finely grained and dispersed distribution of the copper minerals, the complex mineralogy, comparably low copper content, and the possibly high carbonate and organic content in this ore. Leaching at neutral pH seemed worth a try: At neutral pH the abundant carbonates do not need to be dissolved and therewith would not consume excessive amounts of provided acids. Certainly, copper solubility at neutral pH is reduced compared to an acidic environment; however, if copper complexing ligands would be supplied abundantly, copper contents in the mobile phase could easily reach the required economic level. We set up a model system to study the effect of parameters such as pH, microorganisms, microbial metabolites, and organic ligands on covellite leaching to get a better understanding of the processes in copper leaching at pH ≥ 6. With this model system we could show that glutamic acid and the microbial siderophore desferrioxamine B promote covellite dissolution. Both experimental and modeling data showed that pH is an important parameter in covellite dissolution. An increase of pH from 6 to 9 could elevate copper extraction in the presence of glutamic acid by a factor of five. These results have implications for both development of a biotechnological process regarding metal extraction from Kupferschiefer, and for the interaction of bacterial metabolites with the lithosphere and potential mobilization of heavy metals in alkaline environments. Copyright © 2018 Elsevier Ltd. All rights reserved.

Earth Observations taken by the Expedition 22 Crew

NASA Image and Video Library

2009-12-09

ISS022-E-008282 (9 Dec. 2009) --- One of the world?s leading copper mines, Escondida, in the Atacama Desert of Chile, is featured in this image photographed by an Expedition 22 crew member on the International Space Station. The copper mining industry is a major part of the Chilean economy. The mine is located 170 kilometers southeast of Chile?s port city of Antofagasta, in the hyper arid northern Atacama Desert at an elevation of 3,050 meters (approximately 10,000 feet) above sea level. Escondida produces mainly copper concentrates; assisted by gravity, the concentrates are piped as slurry down to the smaller port of Coloso just south of Antofagasta where they are dewatered for shipping. The photograph features a large light tan and gray waste or ?spoil? materials impoundment area (center) of the mine complex. The copper-bearing waste, which is a large proportion of the material excavated from open pits to the north (not in frame), is poured into the impoundment area as a liquid (green region at photo?s center), and dries to the lighter-toned spoil seen in the image. The spoil is held behind a retaining dam, just a little more than one kilometer in length, visible as a straight line at lower left. ?Escondida? means ?hidden? in Spanish, and refers to the fact that the copper ore body was buried beneath hundreds of meters of barren rock and had to be located by a laborious drilling program following a geologic trend established from other copper occurrences.

Chromatographic Separation and Visual Detection on Wicking Microfluidic Devices: Quantitation of Cu2+ in Surface, Ground, and Drinking Water.

PubMed

Bandara, Gayan C; Heist, Christopher A; Remcho, Vincent T

2018-02-20

Copper is widely applied in industrial and technological applications and is an essential micronutrient for humans and animals. However, exposure to high environmental levels of copper, especially through drinking water, can lead to copper toxicity, resulting in severe acute and chronic health effects. Therefore, regular monitoring of aqueous copper ions has become necessary as recent anthropogenic activities have led to elevated environmental concentrations of copper. On-site monitoring processes require an inexpensive, simple, and portable analytical approach capable of generating reliable qualitative and quantitative data efficiently. Membrane-based lateral flow microfluidic devices are ideal candidates as they facilitate rapid, inexpensive, and portable measurements. Here we present a simple, chromatographic separation approach in combination with a visual detection method for Cu 2+ quantitation, performed in a lateral flow microfluidic channel. This method appreciably minimizes interferences by incorporating a nonspecific polymer inclusion membrane (PIM) based assay with a "dot-counting" approach to quantification. In this study, hydrophobic polycaprolactone (PCL)-filled glass microfiber (GMF) membranes were used as the base substrate onto which the PIM was evenly dispensed as an array of dots. The devices thus prepared were then selectively exposed to oxygen radicals through a mask to generate a hydrophilic surface path along which the sample was wicked. Using this approach, copper concentrations from 1 to 20 ppm were quantified from 5 μL samples using only visual observation of the assay device.

Porins Increase Copper Susceptibility of Mycobacterium tuberculosis

PubMed Central

Speer, Alexander; Rowland, Jennifer L.; Haeili, Mehri; Niederweis, Michael

2013-01-01

Copper resistance mechanisms are crucial for many pathogenic bacteria, including Mycobacterium tuberculosis, during infection because the innate immune system utilizes copper ions to kill bacterial intruders. Despite several studies detailing responses of mycobacteria to copper, the pathways by which copper ions cross the mycobacterial cell envelope are unknown. Deletion of porin genes in Mycobacterium smegmatis leads to a severe growth defect on trace copper medium but simultaneously increases tolerance for copper at elevated concentrations, indicating that porins mediate copper uptake across the outer membrane. Heterologous expression of the mycobacterial porin gene mspA reduced growth of M. tuberculosis in the presence of 2.5 μM copper by 40% and completely suppressed growth at 15 μM copper, while wild-type M. tuberculosis reached its normal cell density at that copper concentration. Moreover, the polyamine spermine, a known inhibitor of porin activity in Gram-negative bacteria, enhanced tolerance of M. tuberculosis for copper, suggesting that copper ions utilize endogenous outer membrane channel proteins of M. tuberculosis to gain access to interior cellular compartments. In summary, these findings highlight the outer membrane as the first barrier against copper ions and the role of porins in mediating copper uptake in M. smegmatis and M. tuberculosis. PMID:24013632

Essentiality of copper in humans.

PubMed

Uauy, R; Olivares, M; Gonzalez, M

1998-05-01

The biochemical basis for the essentiality of copper, the adequacy of the dietary copper supply, factors that condition deficiency, and the special conditions of copper nutriture in early infancy are reviewed. New biochemical and crystallographic evidence define copper as being necessary for structural and catalytic properties of cuproenzymes. Mechanisms responsible for the control of cuproprotein gene expression are not known in mammals; however, studies using yeast as a eukaryote model support the existence of a copper-dependent gene regulatory element. Diets in Western countries provide copper below or in the low range of the estimated safe and adequate daily dietary intake. Copper deficiency is usually the consequence of decreased copper stores at birth, inadequate dietary copper intake, poor absorption, elevated requirements induced by rapid growth, or increased copper losses. The most frequent clinical manifestations of copper deficiency are anemia, neutropenia, and bone abnormalities. Recommendations for dietary copper intake and total copper exposure, including that from potable water, should consider that copper is an essential nutrient with potential toxicity if the load exceeds tolerance. A range of safe intakes should be defined for the general population, including a lower safe intake and an upper safe intake, to prevent deficiency as well as toxicity for most of the population.

Hsp60-induced tolerance in the rotifer Brachionus plicatilis exposed to multiple environmental contaminants.

PubMed

Wheelock, C E; Wolfe, M F; Olsen, H; Tjeerdema, R S; Sowby, M L

1999-04-01

Hsp60 induction was selected as a sublethal endpoint of toxicity for Brachionus plicatilis exposed to a water accommodated fraction (WAF) of Prudhoe Bay crude oil (PBCO), a PBCO/dispersant (Corexit 9527(R)) fraction and Corexit 9527(R) alone. To examine the effect of multiple stressors, exposures modeled San Francisco Bay, where copper levels are approximately 5 microgram/L, salinity is 22 per thousand, significant oil transport and refining occurs, and petroleum releases have occurred historically. Rotifers were exposed to copper at 5 microgram/L for 24 h, followed by one of the oil/dispersant preparations for 24 h. Batch-cultured rotifers were used in this study to model wild populations instead of cysts. SDS-PAGE with Western Blotting using hsp60-specific antibodies and chemiluminescent detection were used to isolate, identify, and measure induced hsp60 as a percentage of control values. Both PBCO/dispersant and dispersant alone preparations induced significant levels of hsp60. However, hsp60 expression was reduced to that of controls at high WAF concentrations, suggesting interference with protein synthesis. Rotifers that had been preexposed to copper maintained elevated levels of hsp60 upon treatment with WAF at all concentrations. Results suggest that induction of hsp60 by chronic low-level exposure may serve as a protective mechanism against subsequent or multiple stressors and that hsp60 levels are not additive for the toxicants tested in this study, giving no dose-response relationship. The methods employed in this study could be useful for quantifying hsp60 levels in wild rotifer populations.

Inert electrode containing metal oxides, copper and noble metal

DOEpatents

Ray, Siba P.; Woods, Robert W.; Dawless, Robert K.; Hosler, Robert B.

2001-01-01

A cermet composite material is made by treating at an elevated temperature a mixture comprising a compound of iron and a compound of at least one other metal, together with an alloy or mixture of copper and a noble metal. The alloy or mixture preferably comprises particles having an interior portion containing more copper than noble metal and an exterior portion containing more noble metal than copper. The noble metal is preferably silver. The cermet composite material preferably includes alloy phase portions and a ceramic phase portion. At least part of the ceramic phase portion preferably has a spinel structure.

Inert electrode containing metal oxides, copper and noble metal

DOEpatents

Ray, Siba P.; Woods, Robert W.; Dawless, Robert K.; Hosler, Robert B.

2000-01-01

A cermet composite material is made by treating at an elevated temperature a mixture comprising a compound of iron and a compound of at least one other metal, together with an alloy or mixture of copper and a noble metal. The alloy or mixture preferably comprises particles having an interior portion containing more copper than noble metal and an exterior portion containing more noble metal than copper. The noble metal is preferably silver. The cermet composite material preferably includes alloy phase portions and a ceramic phase portion. At least part of the ceramic phase portion preferably has a spinel structure.

Trace element concentrations in two subpopulations of lesser snow geese from Wrangel Island, Russia

USGS Publications Warehouse

Hui, A.; Takekawa, John Y.; Baranyuk, Vasily V.; Litvin, K.V.

1998-01-01

Lesser snow geese (Anser c. caerulescens) from the Wrangel Island, Russia breeding colony spend the winter in two widely separated areas: the northern subpopulation in southern British Columbia and northern Washington and the southern subpopulation in the Central Valley of California. We examined 19 trace elements in the eggs and livers of geese from these two subpopulations to examine whether geese from the different wintering areas have similar trace element burdens. Eggs collected at the breeding colony from geese of the southern subpopulation had slightly higher levels of manganese, an element that can cause neurological damage and behavioral changes in chicks, than geese of the northern subpopulation. Livers from adult geese collected on the two wintering areas showed significant differences in trace elements including copper, iron, magnesium, molybdenum, and zinc. Copper concentrations in the livers of geese from the southern subpopulation were much higher than those from the northern subpopulation (x¯ = 116 vs. 46 ppm; dry weight). Elevated levels of copper may induce anemia in birds. The differences in trace element concentrations of these two subpopulations may be related to farming practices in their wintering areas. Geese from the northern subpopulation feed in pastures and coastal marshes and migrate along the coast, but geese from the southern subpopulation feed predominantly in rice fields and migrate over farm land. Copper and manganese are major components of fertilizers and fungicides commonly applied during rice cultivation.

Remedial Investigation Concept Plan for Picatinny Arsenal. Volume 2. Descriptions of and Sampling Plans for Remedial Investigation Sites

DTIC Science & Technology

1991-03-22

by sulfur dioxide to convert hexavalent chromium into trivalent chromium , and by sodium hydroxide to promote precipitation. After being transferred...Regulations COD chemical oxygen demand Cr chromium CTF chlorine trifluoride Cu copper 2,4-D 2,4-dichlorophenoxyaoetic acid 11DCE 1,1...the Site. Inorganic results for surface soil showed elevated values for arsenic, cadmium, chromium , lead, and zinc (Table 2.1). These levels are to be

Electronic cigarette aerosols and copper nanoparticles induce mitochondrial stress and promote DNA fragmentation in lung fibroblasts.

PubMed

Lerner, Chad A; Rutagarama, Pierrot; Ahmad, Tanveer; Sundar, Isaac K; Elder, Alison; Rahman, Irfan

2016-09-02

Oxidants or nanoparticles have recently been identified as constituents of aerosols released from various styles of electronic cigarettes (E-cigs). Cells in the lung may be directly exposed to these constituents and harbor reactive properties capable of incurring acute cell injury. Our results show mitochondria are sensitive to both E-cig aerosols and aerosol containing copper nanoparticles when exposed to human lung fibroblasts (HFL-1) using an Air-Liquid Interface culture system, evident by elevated levels of mitochondrial ROS (mtROS). Increased mtROS after aerosol exposure is associated with reduced stability of OxPhos electron transport chain (ETC) complex IV subunit and nuclear DNA fragmentation. Increased levels of IL-8 and IL-6 in HFL-1 conditioned media were also observed. These findings reveal both mitochondrial, genotoxic, and inflammatory stresses are features of direct cell exposure to E-cig aerosols which are ensued by inflammatory duress, raising a concern on deleterious effect of vaping. Copyright © 2016 Elsevier Inc. All rights reserved.

Ignition and Combustion Characteristics of Pure Bulk Metals: Normal-Gravity Test Results

NASA Technical Reports Server (NTRS)

Abbud-Madrid, A.; Fiechtner, G. J.; Branch, M. C.; Daily, J. W.

1994-01-01

An experimental apparatus has been designed for the study of bulk metal ignition under elevated, normal and reduced gravity environments. The present work describes the technical characteristics of the system, the analytical techniques employed, the results obtained from the ignition of a variety of metals subjected to normal gravity conditions and the first results obtained from experiments under elevated gravity. A 1000 W xenon short-arc lamp is used to irradiate the top surface of a cylindrical metal specimen 4 mm in diameter and 4 mm high in a quiescent pure-oxygen environment at 0.1 MPa. Iron, titanium, zirconium, magnesium, zinc, tin, and copper specimens are investigated. All these metals exhibit ignition and combustion behavior varying in strength and speed. Values of ignition temperatures below, above or in the range of the metal melting point are obtained from the temperature records. The emission spectra from the magnesium-oxygen gas-phase reaction reveals the dynamic evolution of the ignition event. Scanning electron microscope and x-ray spectroscopic analysis provide the sequence of oxide formation on the burning of copper samples. Preliminary results on the effect of higher-than-normal gravity levels on the ignition of titanium specimens is presented.

Growth and physiological responses of some Capsicum frutescens varieties to copper stress

NASA Astrophysics Data System (ADS)

Jadid, Nurul; Maziyah, Rizka; Nurcahyani, Desy Dwi; Mubarokah, Nilna Rizqiyah

2017-06-01

Copper (Cu) is an essential micronutrient participating in various physiological processes. However, excessive uptake of this micronutrient could potentially affect plant growth and development as well as plant productivity. In this present work, growth and physiological responses of some Capsicum frustescens varieties to Cu stress were determined. Three C. frutescens varieties used in this work were var. Bara, CF 291, and Genie. In addition, these varieties were treated with different concentration of Cu (0, 30, 70, and 120 ppm). The growth and physiological responses measured in this work included plant height, root length, malondialdehyde (MDA), and chlorophyll. The result showed that all varieties tested relatively displayed plant growth reduction including plant height and root length. Likewise, an increase of MDA level, a major bioindicator for oxidative damage was also found in all varieties following exposure to elevated Cu concentration. Finally, the chlorophyll content was also affected indicated by a decreased amount of chlorophyll, especially in var. CF291. The overall results demonstrated that elevated Cu concentration might decrease C. frutescens productivity where among the three varieties tested, var CF 291 seemed to be the most sensitive varieties to Cu stress.

[Taste disturbance after general anesthesia with classic laryngeal mask airway (CLM)].

PubMed

Arimune, Mutsuaki

2007-07-01

A 27-year-old man underwent the right knee joint operation under general anesthesia with CLM. After the operation, he complained of taste disturbance of the left side of the tongue. We measured electrical taste threshold and the serum level of zinc, copper and iron. The taste threshold was elevated in the two nerve areas of the left side of the tongue (chorda tympani, N. glossopharyngeus) and the serum levels of zinc and iron were low. We concluded that he had been short of zinc and iron and the insertion of CLM had triggered taste disturbance.

Cytotoxicity and genotoxicity of nano - and microparticulate copper oxide: role of solubility and intracellular bioavailability.

PubMed

Semisch, Annetta; Ohle, Julia; Witt, Barbara; Hartwig, Andrea

2014-02-13

Nano- or microscale copper oxide particles (CuO NP, CuO MP) are increasingly applied as catalysts or antimicrobial additives. This increases the risk of adverse health effects, since copper ions are cytotoxic under overload conditions. The extra- and intracellular bioavailability of CuO NP and CuO MP were explored. In addition, different endpoints related to cytotoxicity as well as direct and indirect genotoxicity of the copper oxides and copper chloride (CuCl2) were compared. Comprehensively characterized CuO NP and CuO MP were analysed regarding their copper ion release in model fluids. In all media investigated, CuO NP released far more copper ions than CuO MP, with most pronounced dissolution in artificial lysosomal fluid. CuO NP and CuCl2 caused a pronounced and dose dependent decrease of colony forming ability (CFA) in A549 and HeLa S3 cells, whereas CuO MP exerted no cytotoxicity at concentrations up to 50 μg/mL. Cell death induced by CuO NP was at least in part due to apoptosis, as determined by subdiploid DNA as well as via translocation of the apoptosis inducing factor (AIF) into the cell nucleus. Similarly, only CuO NP induced significant amounts of DNA strand breaks in HeLa S3 cells, whereas all three compounds elevated the level of H2O2-induced DNA strand breaks. Finally, all copper compounds diminished the H2O2-induced poly(ADP-ribosyl)ation, catalysed predominantly by poly(ADP-ribose)polymerase-1 (PARP-1); here, again, CuO NP exerted the strongest effect. Copper derived from CuO NP, CuO MP and CuCl2 accumulated in the soluble cytoplasmic and nuclear fractions of A549 cells, yielding similar concentrations in the cytoplasm but highest concentrations in the nucleus in case of CuO NP. The results support the high cytotoxicity of CuO NP and CuCl2 and the missing cytotoxicity of CuO MP under the conditions applied. For these differences in cytotoxicity, extracellular copper ion levels due to dissolution of particles as well as differences in physicochemical properties of the particles like surface area may be of major relevance. Regarding direct and indirect genotoxicity, especially the high copper content in the cell nucleus derived after cell treatment with CuO NP appears to be decisive.

Cytotoxicity and genotoxicity of nano - and microparticulate copper oxide: role of solubility and intracellular bioavailability

PubMed Central

2014-01-01

Background Nano- or microscale copper oxide particles (CuO NP, CuO MP) are increasingly applied as catalysts or antimicrobial additives. This increases the risk of adverse health effects, since copper ions are cytotoxic under overload conditions. Methods The extra- and intracellular bioavailability of CuO NP and CuO MP were explored. In addition, different endpoints related to cytotoxicity as well as direct and indirect genotoxicity of the copper oxides and copper chloride (CuCl2) were compared. Results Comprehensively characterized CuO NP and CuO MP were analysed regarding their copper ion release in model fluids. In all media investigated, CuO NP released far more copper ions than CuO MP, with most pronounced dissolution in artificial lysosomal fluid. CuO NP and CuCl2 caused a pronounced and dose dependent decrease of colony forming ability (CFA) in A549 and HeLa S3 cells, whereas CuO MP exerted no cytotoxicity at concentrations up to 50 μg/mL. Cell death induced by CuO NP was at least in part due to apoptosis, as determined by subdiploid DNA as well as via translocation of the apoptosis inducing factor (AIF) into the cell nucleus. Similarly, only CuO NP induced significant amounts of DNA strand breaks in HeLa S3 cells, whereas all three compounds elevated the level of H2O2-induced DNA strand breaks. Finally, all copper compounds diminished the H2O2-induced poly(ADP-ribosyl)ation, catalysed predominantly by poly(ADP-ribose)polymerase-1 (PARP-1); here, again, CuO NP exerted the strongest effect. Copper derived from CuO NP, CuO MP and CuCl2 accumulated in the soluble cytoplasmic and nuclear fractions of A549 cells, yielding similar concentrations in the cytoplasm but highest concentrations in the nucleus in case of CuO NP. Conclusions The results support the high cytotoxicity of CuO NP and CuCl2 and the missing cytotoxicity of CuO MP under the conditions applied. For these differences in cytotoxicity, extracellular copper ion levels due to dissolution of particles as well as differences in physicochemical properties of the particles like surface area may be of major relevance. Regarding direct and indirect genotoxicity, especially the high copper content in the cell nucleus derived after cell treatment with CuO NP appears to be decisive. PMID:24520990

Distribution and Fate of Energetics on DoD Test and Training Ranges: Interim Report 5

DTIC Science & Technology

2005-04-01

aluminum, arsenic, and iron were naturally elevated (Ampleman et al. 2003). A cadmium concentration at 0.3 ppb was observed in one sample. Copper...copper concentration was twice the CCME criterion. Iron was also observed in the Shaver River sample at three times the CCME criterion. Concentrations...mainly in C-295, the first site visited. Copper and iron were found at high concentrations in almost all samples; however, only one or two samples showed

Industrial Tests to Modify Molten Copper Slag for Improvement of Copper Recovery

NASA Astrophysics Data System (ADS)

Guo, Zhengqi; Zhu, Deqing; Pan, Jian; Zhang, Feng; Yang, Congcong

2018-04-01

In this article, to improve the recovery of copper from copper slag by flotation process, industrial tests of the modification process involving addition of a composite additive into molten copper slag were conducted, and the modified slag was subjected to the flotation process to confirm the modification effect. The phase evolution of the slag in the modification process was revealed by thermodynamic calculations, x-ray diffraction, optical microscopy and scanning electron microscopy. The results show that more copper was transformed and enriched in copper sulfide phases. The magnetite content in the modified slag decreased, and that of "FeO" increased correspondingly, leading to a better fluidity of the molten slag, which improved the aggregation and growth of fine particles of the copper sulfide minerals. Closed-circuit flotation tests of the original and modified slags were conducted, and the results show that the copper recovery increased obviously from 69.15% to 73.38%, and the copper grade of concentrates was elevated slightly from 20.24% to 21.69%, further confirming that the industrial tests of the modification process were successful. Hence, the modification process has a bright future in industrial applications for enhancing the recovery of copper from the copper slag.

Process for removing copper in a recoverable form from solid scrap metal

DOEpatents

Hartman, Alan D.; Oden, Laurance L.; White, Jack C.

1995-01-01

A process for removing copper in a recoverable form from a copper/solid ferrous scrap metal mix is disclosed. The process begins by placing a copper/solid ferrous scrap metal mix into a reactor vessel. The atmosphere within the reactor vessel is purged with an inert gas or oxidizing while the reactor vessel is heated in the area of the copper/solid ferrous scrap metal mix to raise the temperature within the reactor vessel to a selected elevated temperature. Air is introduced into the reactor vessel and thereafter hydrogen chloride is introduced into the reactor vessel to obtain a desired air-hydrogen chloride mix. The air-hydrogen chloride mix is operable to form an oxidizing and chloridizing atmosphere which provides a protective oxide coating on the surface of the solid ferrous scrap metal in the mix and simultaneously oxidizes/chloridizes the copper in the mix to convert the copper to a copper monochloride gas for transport away from the solid ferrous scrap metal. After the copper is completely removed from the copper/solid ferrous scrap metal mix, the flows of air and hydrogen chloride are stopped and the copper monochloride gas is collected for conversion to a recoverable copper species.

Synchrotron radiation analysis of possible correlations between metal status in human cementum and periodontal disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, R.R.; Naftel, S.J.; Nelson, A.J.

2010-03-16

Periodontitis is a serious disease that affects up to 50% of an adult population. It is a chronic condition involving inflammation of the periodontal ligament and associated tissues leading to eventual tooth loss. Some evidence suggests that trace metals, especially zinc and copper, may be involved in the onset and severity of periodontitis. Thus we have used synchrotron X-ray fluorescence imaging on cross sections of diseased and healthy teeth using a microbeam to explore the distribution of trace metals in cementum and adhering plaque. The comparison between diseased and healthy teeth indicates that there are elevated levels of zinc, coppermore » and nickel in diseased teeth as opposed to healthy teeth. This preliminary correlation between elevated levels of trace metals in the cementum and plaque of diseased teeth suggests that metals may play a role in the progress of periodontitis.« less

Effects of nonylphenol and ethinylestradiol on copper redhorse (Moxostoma hubbsi), an endangered species.

PubMed

Maltais, Domynick; Roy, Robert L

2014-10-01

The copper redhorse, Moxostoma hubbsi, is an endangered species endemic to Quebec. The presence of contaminants, in particular endocrine disrupting chemicals (EDCs), in its habitat has been advanced as partly responsible for the reproductive difficulties encountered by the species. In the present study, immature copper redhorse were exposed to the estrogenic surfactant nonylphenol (NP; 1, 10 and 50µg/l) and the synthetic estrogen 17α-ethinylestradiol (EE2; 10ng/l) for 21 days in a flow-through system. The endpoints investigated included general health indicators (hepatosomatic index and hematocrit), thyroid hormones, sex steroids, brain aromatase activity, plasma and mucus vitellogenin (VTG), cytochrome P4501A protein expression and ethoxyresorufin-O-deethylase activity, heat shock protein 70 (HSP70) and muscle acetylcholinesterase. Exposure to 10ng EE2/l significantly increased brain aromatase activity. Exposure to 50µg NP/l resulted in a significant reduction of plasma testosterone concentrations and a significant induction of hepatic HSP70 protein expression. NP at 50µg/l also induced plasma and mucus VTG. The presence of elevated VTG levels in the surface mucus of immature copper redhorse exposed to NP, and its correlation to plasma VTG, supports the use of mucus VTG as a non-invasive biomarker to evaluate copper redhorse exposure to EDCs in the environment and contribute to restoration efforts of the species. The results of the present study indicate that exposure to high environmentally relevant concentrations of NP and EE2 can affect molecular endpoints related to reproduction in the copper redhorse. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

Fetal and neonatal iron deficiency but not copper deficiency increases vascular complexity in the developing rat brain

PubMed Central

Bastian, Thomas W.; Santarriaga, Stephanie; Nguyen, Thu An; Prohaska, Joseph R.; Georgieff, Michael K.; Anderson, Grant W.

2015-01-01

Objectives Anemia caused by nutritional deficiencies, such as iron and copper deficiencies, is a global health problem. Iron and copper deficiencies have their most profound effect on the developing fetus/infant, leading to brain development deficits and poor cognitive outcomes. Tissue iron depletion or chronic anemia can induce cellular hypoxic signaling. In mice, chronic hypoxia induces a compensatory increase in brain blood vessel outgrowth. We hypothesized that developmental anemia, due to iron or copper deficiencies, induces angiogenesis/vasculogenesis in the neonatal brain. Methods To test our hypothesis, three independent experiments were performed where pregnant rats were fed iron- or copper-deficient diets from gestational day 2 through mid-lactation. Effects on the neonatal brain vasculature were determined using qPCR to assess mRNA levels of angiogenesis/vasculogenesis-associated genes and GLUT1 immunohistochemistry (IHC) to assess brain blood vessel density and complexity. Results Iron deficiency, but not copper deficiency, increased mRNA expression of brain endothelial cell- and angiogenesis/vasculogenesis-associated genes (i.e. Glut1, Vwf, Vegfa, Ang2, Cxcl12, and Flk1) in the neonatal brain, suggesting increased cerebrovascular density. Iron deficiency also increased hippocampal and cerebral cortical blood vessel branching by 62% and 78%, respectively. Discussion This study demonstrates increased blood vessel complexity in the neonatal iron-deficient brain, which is likely due to elevated angiogenic/vasculogenic signaling. At least initially, this is probably an adaptive response to maintain metabolic substrate homeostasis in the developing iron-deficient brain. However, this may also contribute to long-term neurodevelopmental deficits. PMID:26177275

CopZ from Bacillus subtilis interacts in vivo with a copper exporting CPx-type ATPase CopA.

PubMed

Radford, David S; Kihlken, Margaret A; Borrelly, Gilles P M; Harwood, Colin R; Le Brun, Nick E; Cavet, Jennifer S

2003-03-14

The structure of the hypothetical copper-metallochaperone CopZ from Bacillus subtilis and its predicted partner CopA have been studied but their respective contributions to copper export, -import, -sequestration and -supply are unknown. DeltacopA was hypersensitive to copper and contained more copper atoms cell(-1) than wild-type. Expression from the copA operator-promoter increased in elevated copper (not other metals), consistent with a role in copper export. A bacterial two-hybrid assay revealed in vivo interaction between CopZ and the N-terminal domain of CopA but not that of a related transporter, YvgW, involved in cadmium-resistance. Activity of copper-requiring cytochrome caa(3) oxidase was retained in deltacopZ and deltacopA. DeltacopZ was only slightly copper-hypersensitive but deltacopZ/deltacopA was more sensitive than deltacopA, implying some action of CopZ that is independent of CopA. Significantly, deltacopZ contained fewer copper atoms cell(-1) than wild-type under these conditions. CopZ makes a net contribution to copper sequestration and/or recycling exceeding any donation to CopA for export.

Rate and Regulation of Copper Transport by Human Copper Transporter 1 (hCTR1)*

PubMed Central

Maryon, Edward B.; Molloy, Shannon A.; Ivy, Kristin; Yu, Huijun; Kaplan, Jack H.

2013-01-01

Human copper transporter 1 (hCTR1) is a homotrimer of a 190-amino acid monomer having three transmembrane domains believed to form a pore for copper permeation through the plasma membrane. The hCTR1-mediated copper transport mechanism is not well understood, nor has any measurement been made of the rate at which copper ions are transported by hCTR1. In this study, we estimated the rate of copper transport by the hCTR1 trimer in cultured cells using 64Cu uptake assays and quantification of plasma membrane hCTR1. For endogenous hCTR1, we estimated a turnover number of about 10 ions/trimer/s. When overexpressed in HEK293 cells, a second transmembrane domain mutant of hCTR1 (H139R) had a 3-fold higher Km value and a 4-fold higher turnover number than WT. Truncations of the intracellular C-terminal tail and an AAA substitution of the putative metal-binding HCH C-terminal tripeptide (thought to be required for transport) also exhibited elevated transport rates and Km values when compared with WT hCTR1. Unlike WT hCTR1, H139R and the C-terminal mutants did not undergo regulatory endocytosis in elevated copper. hCTR1 mutants combining methionine substitutions that block transport (M150L,M154L) on the extracellular side of the pore and the high transport H139R or AAA intracellular side mutations exhibited the blocked transport of M150L,M154L, confirming that Cu+ first interacts with the methionines during permeation. Our results show that hCTR1 elements on the intracellular side of the hCTR1 pore, including the carboxyl tail, are not essential for permeation, but serve to regulate the rate of copper entry. PMID:23658018

[Copper intake and blood levels as risk factors for atheromatous disease].

PubMed

Albala, C; Salazar, G; Vío, F; Araya, F; Feuerhacke, W; Olivares, S; Alvarez, G

1997-08-01

Copper is part of antioxidant enzymes and could have a cardiovascular protective effect. A higher cardiovascular risk has been associated with high as well as low plasma copper levels. To search for differences in copper intake and plasma levels between patients with coronary artery or cerebrovascular diseases and normal subjects. Zinc and copper intake, plasma levels and serum lipid levels were measured in 20 patients with cerebrovascular disease, 20 patients with an acute myocardial infarction and 40 subjects hospitalized for elective surgery, that served as controls. Copper and zinc intake was below recommended allowances in all subjects. Serum zinc and copper levels did not differ in the three study groups. In patients with myocardial infarction a weak correlation was found between serum copper and total cholesterol (r = 0.24; p < 0.05) and LDL cholesterol (r = 0.31; p < 0.05). No differences in copper levels were found in subjects with atherosclerosis and controls. The correlation between serum copper and cholesterol deserves further investigation.

Relations of benthic macroinvertebrates to concentrations of trace elements in water, streambed sediments, and transplanted bryophytes and stream habitat conditions in nonmining and mining areas of the upper Colorado River basin, Colorado, 1995-98

USGS Publications Warehouse

Mize, Scott V.; Deacon, Jeffrey R.

2002-01-01

Intensive mining activity and highly mineralized rock formations have had significant impacts on surface-water and streambed-sediment quality and aquatic life within the upper reaches of the Uncompahgre River in western Colorado. A synoptic study by the U.S. Geological Survey National Water-Quality Assessment Program was completed in the upper Uncompahgre River Basin in 1998 to better understand the relations of trace elements (with emphasis on aluminum, arsenic, copper, iron, lead, and zinc concentrations) in water, streambed sediment, and aquatic life. Water-chemistry, streambed-sediment, and benthic macroinvertebrate samples were collected during low-flow conditions between October 1995 and July 1998 at five sites on the upper Uncompahgre River, all downstream from historical mining, and at three sites in drainage basins of the Upper Colorado River where mining has not occurred. Aquatic bryophytes were transplanted to all sites for 15 days of exposure to the water column during which time field parameters were measured and chemical water-quality and benthic macroinvertebrate samples were collected. Stream habitat characteristics also were documented at each site. Certain attributes of surface-water chemistry among streams were significantly different. Concentrations of total aluminum, copper, iron, lead, and zinc in the water column and concentrations of dissolved aluminum, copper, and zinc were significantly different between nonmining and mining sites. Some sites associated with mining exceeded Colorado acute aquatic-life standards for aluminum, copper, and zinc and exceeded Colorado chronic aquatic-life standards for aluminum, copper, iron, lead, and zinc. Concentrations of copper, lead, and zinc in streambed sediments were significantly different between nonmining and mining sites. Generally, concentrations of arsenic, copper, lead, and zinc in streambed sediments at mining sites exceeded the Canadian Sediment Quality Guidelines probable effect level (PEL), except at two mining sites where concentrations of copper and zinc were below the PEL. Concentrations of arsenic, copper, iron, and lead in transplanted bryophytes were significantly different between nonmining and mining sites. Bioconcentration factors calculated for 15-day exposure using one-half of the minimum reporting level were significantly different between nonmining and mining sites. In general, concentrations of trace elements in streambed sediment and transplanted bryophytes were more closely correlated than were the concentrations of trace elements in the water column with streambed sediments or concentrations in the water column with transplanted bryophytes. Stream habitat was rated as optimal to suboptimal using the U.S. Environmental Protection Agency Rapid Bioassessment Protocols for all sites in the study area. Generally, stream habitat conditions were similar at nonmining compared to mining sites and were suitable for diverse macroinvertebrate communities. All study sites had optimal instream habitat except two mining sites with suboptimal instream habitat because of disturbances in stream habitat. The benthic macroinvertebrate community composition at nonmining sites and mining sites differed. Mining sites had significantly lower total abundance of macroinvertebrates, fewer numbers of taxa, and lower dominance of Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies), and a larger percentage of tolerant species than did nonmining sites. The predominance of Baetis sp. (mayflies), Hydropsychidae (caddisflies), and large percentage of Orthocladiinae chironomids (midges) at mining sites indicated that these species may be tolerant to elevated trace-element concentrations. The absence of Heptageniidae (mayflies), Chloroperlidae (stoneflies), and Rhyacophila sp. (caddisflies) at mining sites indicated that these species may be sensitive to elevated trace-element concentrations. Comparison of field parameters and

Thermal conductivity and thermal expansion of graphite fiber/copper matrix composites

NASA Technical Reports Server (NTRS)

Ellis, David L.; Mcdanels, David L.

1991-01-01

The high specific conductivity of graphite fiber/copper matrix (Gr/Cu) composites offers great potential for high heat flux structures operating at elevated temperatures. To determine the feasibility of applying Gr/Cu composites to high heat flux structures, composite plates were fabricated using unidirectional and cross-plied pitch-based P100 graphite fibers in a pure copper matrix. Thermal conductivity of the composites was measured from room temperature to 1073 K, and thermal expansion was measured from room temperature to 1050 K. The longitudinal thermal conductivity, parallel to the fiber direction, was comparable to pure copper. The transverse thermal conductivity, normal to the fiber direction, was less than that of pure copper and decreased with increasing fiber content. The longitudinal thermal expansion decreased with increasing fiber content. The transverse thermal expansion was greater than pure copper and nearly independent of fiber content.

Thermal conductivity and thermal expansion of graphite fiber-reinforced copper matrix composites

NASA Technical Reports Server (NTRS)

Ellis, David L.; Mcdanels, David L.

1993-01-01

The high specific conductivity of graphite fiber/copper matrix (Gr/Cu) composites offers great potential for high heat flux structures operating at elevated temperatures. To determine the feasibility of applying Gr/Cu composites to high heat flux structures, composite plates were fabricated using unidirectional and cross-plied pitch-based P100 graphite fibers in a pure copper matrix. Thermal conductivity of the composites was measured from room temperature to 1073 K, and thermal expansion was measured from room temperature to 1050 K. The longitudinal thermal conductivity, parallel to the fiber direction, was comparable to pure copper. The transverse thermal conductivity, normal to the fiber direction, was less than that of pure copper and decreased with increasing fiber content. The longitudinal thermal expansion decreased with increasing fiber content. The transverse thermal expansion was greater than pure copper and nearly independent of fiber content.

Iron, zinc, and copper in retinal physiology and disease.

PubMed

Ugarte, Marta; Osborne, Neville N; Brown, Laurence A; Bishop, Paul N

2013-01-01

The essential trace metals iron, zinc, and copper play important roles both in retinal physiology and disease. They are involved in various retinal functions such as phototransduction, the visual cycle, and the process of neurotransmission, being tightly bound to proteins and other molecules to regulate their structure and/or function or as unbound free metal ions. Elevated levels of "free" or loosely bound metal ions can exert toxic effects, and in order to maintain homeostatic levels to protect retinal cells from their toxicity, appropriate mechanisms exist such as metal transporters, chaperones, and the presence of certain storage molecules that tightly bind metals to form nontoxic products. The pathways to maintain homeostatic levels of metals are closely interlinked, with various metabolic pathways directly and/or indirectly affecting their concentrations, compartmentalization, and oxidation/reduction states. Retinal deficiency or excess of these metals can result from systemic depletion and/or overload or from mutations in genes involved in maintaining retinal metal homeostasis, and this is associated with retinal dysfunction and pathology. Iron accumulation in the retina, a characteristic of aging, may be involved in the pathogenesis of retinal diseases such as age-related macular degeneration (AMD). Zinc deficiency is associated with poor dark adaptation. Zinc levels in the human retina and RPE decrease with age in AMD. Copper deficiency is associated with optic neuropathy, but retinal function is maintained. The changes in iron and zinc homeostasis in AMD have led to the speculation that iron chelation and/or zinc supplements may help in its treatment. Copyright © 2013 Elsevier Inc. All rights reserved.

Controlled atmosphere for fabrication of cermet electrodes

DOEpatents

Ray, Siba P.; Woods, Robert W.

1998-01-01

A process for making an inert electrode composite wherein a metal oxide and a metal are reacted in a gaseous atmosphere at an elevated temperature of at least about 750.degree. C. The metal oxide is at least one of the nickel, iron, tin, zinc and zirconium oxides and the metal is copper, silver, a mixture of copper and silver or a copper-silver alloy. The gaseous atmosphere has an oxygen content that is controlled at about 5-3000 ppm in order to obtain a desired composition in the resulting composite.

Controlled atmosphere for fabrication of cermet electrodes

DOEpatents

Ray, S.P.; Woods, R.W.

1998-08-11

A process is disclosed for making an inert electrode composite wherein a metal oxide and a metal are reacted in a gaseous atmosphere at an elevated temperature of at least about 750 C. The metal oxide is at least one of the nickel, iron, tin, zinc and zirconium oxides and the metal is copper, silver, a mixture of copper and silver or a copper-silver alloy. The gaseous atmosphere has an oxygen content that is controlled at about 5--3000 ppm in order to obtain a desired composition in the resulting composite. 2 figs.

Effect of environmental lead pollution on blood lead levels in traffic police constables in Islamabad, Pakistan.

PubMed

Agha, Farida; Sadaruddin, Agha; Khatoon, Naz

2005-10-01

To determine the blood lead levels and trace elements (copper and manganese) in traffic police constables in Islamabad in order to assess the effects of environmental pollution on the levels of metals in body fluids. Blood samples were collected from 47 male traffic police constables, 21 to 45 years of age, posted in different areas of Islamabad and controlling traffic from 3 months to 18 years, 8 hours/day, 6 days/week. Adolescent males (13-19 years), residing in comparatively clean and very low traffic areas were included as controls. Blood lead, copper, and manganese concentrations were estimated by atomic absorption spectrophotometry. The mean blood lead level among constables (27.27 microg/dl) was significantly (p<0.0001) high as compared to controls (3.22 microg/dl). Twenty one percent constables had elevated blood lead levels (over 25 microg/dl) and 13% had levels above the safety limit (40 microg/dl). No correlation was found between blood lead levels and length of service. No significant difference was found in the mean values for copper between traffic constables (93.49 microg/dl) and controls (71.15 microg/dl). The mean blood manganese levels in traffic constables (21.94 microg/dl) were significantly (p<0.0001) higher than in controls (1.70 microg/dl). The mean blood lead levels were significantly high in traffic constables of Karachi (47.7 microg/dl) as compared to Islamabad (27.2 microg/dl), which shows direct relation of rise in blood lead levels with vehicle exhaust. Environmental lead pollution is associated with an increased blood lead concentration in those who are regularly exposed to vehicle exhaust in high traffic areas. The degree of lead pollution arising from vehicle exhaust differs in Karachi and Islamabad. Exposure to air containing dust particles rich in manganese may affect blood manganese levels.

Effects of Aqueous Extracts of Chicory and Milk Thistle on Serum Concentrations of Copper, Zinc, and Manganese in Tamoxifen-Treated Rats.

PubMed

Abbasalipourkabir, Roghayeh; Ziamajidi, Nasrin; Nasiri, Abolfazl; Behrouj, Hamid

2016-09-01

Some medications may change trace element levels in the body. Extracts of various plants, due to having the several elements, can have beneficial effects. Consumption of herbal extracts with chemical drugs may reduce adverse effects of medication. The goal of this study was to evaluate copper (Cu), zinc (Zn), and manganese (Mn) concentrations in serum of rats treated with tamoxifen, chicory, and/or milk thistle extracts. Therefore, 36 adult female Wistar rats were divided into six groups: normal control, chicory control, milk thistle control, tamoxifen, tamoxifen-chicory, and tamoxifen-milk thistle. At the end of the study, the blood samples were collected and sera isolated by centrifugation and analyzed by the atomic absorption spectrophotometry for Cu, Zn, and Mn levels. The Zn concentration increased in milk thistle-supplemented groups. The Cu level increased in the chicory control group only. Tamoxifen had no affect on Cu, Zn, and Mn levels, but seed extract of milk thistle increased Zn concentration, and chicory root extract increased Cu concentration. Although elevated levels of Cu in rats receiving tamoxifen-chicory were milder than rats treated only with chicory, it seems that the extract and tamoxifen impact on the Cu are in conflict with each other.

Development of graphite/copper composites utilizing engineered interfaces. M.S. Thesis Final Report

NASA Technical Reports Server (NTRS)

Devincent, Sandra M.

1991-01-01

In situ measurements of graphite/copper alloy contact angles were made using the sessile drop method. The interfacial energy values obtained from these measurements were then applied to a model for the fiber matrix interfacial debonding phenomenon found in graphite/copper composites. The formation obtained from the sessile drop tests led to the development of a copper alloy that suitably wets graphite. Characterization of graphite/copper alloy interfaces subjected to elevated temperatures was conducted using Scanning Electron Microscopy, Energy Dispersive Spectroscopy, Auger Electron Spectroscopy, and X Ray Diffraction analyses. These analyses indicated that during sessile drop tests conducted at 1130 C for 1 hour, copper alloys containing greater than 0.98 at pct chromium form continuous reaction layers of approx. 10 microns in thickness. The reaction layers are adherent to the graphite surface. The copper wets the reaction layer to form a contact angle of 60 deg or less. X ray diffraction results indicate that the reaction layer is Cr3C2.

Fracture toughness of copper-base alloys for ITER applications: A preliminary report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alexander, D.J.; Zinkle, S.J.; Rowcliffe, A.F.

1997-04-01

Oxide-dispersion strengthened copper alloys and a precipitation-hardened copper-nickel-beryllium alloy showed a significant reduction in toughness at elevated temperature (250{degrees}C). This decrease in toughness was much larger than would be expected from the relatively modest changes in the tensile properties over the same temperature range. However, a copper-chromium-zirconium alloy strengthened by precipitation showed only a small decrease in toughness at the higher temperatures. The embrittled alloys showed a transition in fracture mode, from transgranular microvoid coalescence at room temperature to intergranular with localized ductility at high temperatures. The Cu-Cr-Zr alloy maintained the ductile microvoid coalescence failure mode at all test temperatures.

The effectiveness of surface liming in ameliorating the phytotoxic effects of soil contaminated by copper acid leach pad solution in an arid ecosystem

NASA Astrophysics Data System (ADS)

Golos, Peter

2016-04-01

Revegetation of sites following soil contamination can be challenging especially in identifying the most effective method for ameliorating phytotoxic effects in arid ecosystems. This study at a copper mine in the Great Sandy Desert of Western Australia investigated vegetation restoration of a site contaminated by acid (H2SO4) leach pad solution. Elevated soil copper at low soil pH is phytotoxic to plant roots inhibiting root elongation. In arid ecosystems where rapid root growth is crucial for seedling survival post germination physical or chemical barriers to root growth need to be identified and ameliorated. Initial attempt at rehabilitation of contaminated site with hydrated lime (CaOH2) at 2 tonnes/ha followed by ripping to 30 cm depth then seeding was ineffective as successful seedling emergence was followed by over 90% seedling mortality which was 10-fold greater than seedling mortality in an uncontaminated reference site. High mortality was attributed to seedling roots being impededed as soil water was more than 3-fold greater at 5 to 40 cm depth in contaminated site than reference site. In response to high seedling mortality after emergence test pits were dug to 1 m deep to collect soil samples at 10 cm intervals for phytotoxicity testing and to measure soil pH-CaCl2, copper (DPTA ion extraction), electrical conductivity and gravimetric water content in three replicate pits at three replicate sites. Also, soil impedance was measured down the soil profile at 5 cm intervals at six replicate points/pit. For phytotoxicity testing soil samples were placed into three replicate plastic pots/sample and seeded with 10 seeds of Avena sativa and watered daily. Seedlings were harvested after at least two weeks after seedling emergence and rooting depth in pots measured. There was no difference in seedling emergence and survival of seedlings between contaminated and uncontaminated soil samples however mean seedling root growth was significantly lower in soil samples collected at >10 cm depth than the control. Mean soil pH at 0-10 cm was higher (>7.2) at all sites treated with lime compared to uncontaminated soil (5.5). At depths greater than 10 cm soil pH was <4.6. Soil copper was >16 mg/kg in all contaminated soil samples compared to 0.5 mg/kg in control. High seedling mortality in contaminated site is attributed to low soil pH and elevated soil copper levels which inhibited plant root growth and hence access to soil water. While surface liming of soil increased soil pH ameliorating the effect of elevated soil copper, this was only effective in the top 10 cm due to low solubility of hydrated lime. To improve seedling survival lime will need to be incorporated into the contaminated soil profile to allow plants to access soil water at depth. This study highlights the importance of the need to assess the phytotoxic effects of soil contamination and the effectiveness of amelioration treatments and with proper reference to its ecological context. To improve the success of vegetation restoration of sites contaminated with acidic copper solution, lime needs to be incorporated into the contaminated soil profile to allow plant roots to access soil water at depth. This study highlights the importance of the need to assess the phytotoxic effects of soil contamination and the effectiveness of amelioration treatments and with proper reference to its ecological context.

Copper tolerance in clones of Agrostis gigantea from a mine waste site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hogan, G.D.; Courtin, G.M.; Rauser, W.E.

1977-04-15

A mine waste site from Sudbury, Ontario, contaminated with heavy metals is described. The dominant vegetative cover was formed by two grasses: Agrostis gigantea Roth. and Agrostis scabra Willd. Testing of 10 clones of A. gigantea from the roast bed and an adjoining area for copper tolerance showed that two clones collected from the roast bed were tolerant to increased copper levels. Copper tolerance was found in clones growing on soils with high copper contents and low pHs. The combination of high copper content and low pH brought about a high level of extractable copper within the soil. Soils withmore » equally high copper levels but higher pHs and therefore low extractable-copper levels did not support copper-tolerant clones.« less

Concentrations of Surface-Dust Metals in Native American Jewelry-Making Homes in Zuni Pueblo, New Mexico

PubMed Central

Gonzales, Melissa; Shah, Vallabh; Bobelu, Arlene; Qualls, Clifford; Natachu, Kathy; Bobelu, Jeanette; Jamon, Eunice; Neha, Donica; Paine, Susan; Zager, Philip

2013-01-01

This pilot study was conducted to identify the metals used by home-based Native American jewelry makers, to quantify the metals in dust samples taken from jewelers’ homes, and to compare these concentrations with background levels from control homes in which jewelry was not made. Participants were recruited from Zuni Pueblo, New Mexico. Surface dust samples were collected from the work and living areas of 20 jewelers’ homes, and from the living areas of 20 control homes. Silver, copper, tin, boron, nickel, zinc, lead, and cadmium were significantly higher in work areas than in living areas of jewelry-making homes (p≤ 0.02). Silver, copper, nickel, and antimony were significantly higher in living areas of jewelers’ homes compared with control homes (p ≤ 0.04). Ventilation measures did not effectively reduce metal concentrations in jewelers’ homes; concentrations in nonwork areas remained elevated. PMID:16201670

Copper uptake and retention in liver parenchymal cells isolated from nutritionally copper-deficient rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van den Berg, G.J.; de Goeij, J.J.; Bock, I.

1991-08-01

Copper uptake and retention were studied in primary cultures of liver parenchymal cells isolated from copper-deficient rats. Male Sprague-Dawley rats were fed a copper-deficient diet (less than 1 mg Cu/kg) for 10 wk. Copper-deficient rats were characterized by low copper concentrations in plasma and liver, anemia, low plasma ceruloplasmin oxidase activity and increased 64Cu whole-body retention. Freshly isolated liver parenchymal cells from copper-deficient rats showed a higher 64Cu influx, which was associated with a higher apparent Vmax of 45 {plus minus} 4 pmol Cu.mg protein-1.min-1 as compared with 30 {plus minus} 3 pmol Cu.mg protein-1.min-1 for cells isolated from copper-sufficientmore » rats. No significant difference in the apparent Km (approximately 30 mumol/L) was observed. Relative 64Cu efflux from cells from copper-deficient rats was significantly smaller than the efflux from cells from copper-sufficient rats after prelabeling as determined by 2-h efflux experiments. Analysis of the medium after efflux from cells from copper-deficient rats showed elevated protein-associated 64Cu, suggesting a higher incorporation of radioactive copper during metalloprotein synthesis. Effects of copper deficiency persist in primary cultures of parenchymal cells derived from copper-deficient rats, and short-term cultures of these cells offer a prospect for the study of cell biological aspects of the metabolic adaptation of the liver to copper deficiency.« less

Serum copper levels in users of multiload intra-uterine contraceptive devices.

PubMed

Arowojolu, A O; Otolorin, E O; Ladipo, O A

1989-12-01

The systemic absorption of copper incorporated into multiload intra-uterine contraceptive devices (IUDs), as indicated by serum copper levels in users of such devices, was assessed in a prospective longitudinal study. One hundred and ten healthy Nigerian women using either multiload copper 250 (MLCU 250) or multiload copper 375 (MLCU 375) IUDs participated in the study. Their serum copper levels were estimated serially during 12 months of continuous use of the devices. The mean (+/- s.e.m.) pre-insertion serum copper levels of our subjects using MLCU 250 (17.0 +/- 3 mumol/l) and MLCU 375 (16.7 +/- 0.5 mumol/l) were found to be lower than those reported in Americans (22.2 mumol/l) and in Germans (20.2 mumol/l), although similar to levels in Indians (17.0 mumol/l). There was no significant difference in the mean serum copper levels estimated before and after 1 month of continuous use of the device. Serial estimations of the serum copper levels in users showed that there was no alteration in these levels after a period of 12 months of continuous IUD use. We therefore conclude that the copper incorporated into multiload IUDs appears not to influence the concentration of serum copper of users.

Factors affecting catalysis of copper corrosion products in NDMA formation from DMA in simulated premise plumbing.

PubMed

Zhang, Hong; Andrews, Susan A

2013-11-01

This study investigated the effects of corrosion products of copper, a metal commonly employed in household plumbing systems, on N-nitrosodimethylamine (NDMA) formation from a known NDMA precursor, dimethylamine (DMA). Copper-catalyzed NDMA formation increased with increasing copper concentrations, DMA concentrations, alkalinity and hardness, but decreased with increasing natural organic matter (NOM) concentration. pH influenced the speciation of chloramine and the interactions of copper with DMA. The transformation of monochloramine (NH2Cl) to dichloramine and complexation of copper with DMA were involved in elevating the formation of NDMA by copper at pH 7.0. The inhibiting effect of NOM on copper catalysis was attributed to the rapid consumption of NH2Cl by NOM and/or the competitive complexation of NOM with copper to limit the formation of DMA-copper complexes. Hardness ions, as represented by Ca(2+), also competed with copper for binding sites on NOM, thereby weakening the inhibitory effect of NOM on NDMA formation. Common copper corrosion products also participated in these reactions but in different ways. Aqueous copper released from malachite [Cu2CO3(OH)2] was shown to promote NDMA formation while NDMA formation decreased in the presence of CuO, most likely due to the adsorption of DMA. Copyright © 2013 Elsevier Ltd. All rights reserved.

Evaluating the spatial distribution of pollutants and associated maintenance requirements in an 11 year-old bioretention cell in urban Charlotte, NC.

PubMed

Johnson, Jeffrey P; Hunt, William F

2016-12-15

Bioretention cells (BRCs) are an increasingly popular Stormwater Control Measure used to mitigate the hydrologic and water quality impacts of urbanization. Previous BRC research has demonstrated a strong capacity for pollutant removal; however, long-term sequestration of pollutants within soil media can elevate concentrations to levels fostering environmental and human health risks. Soil media samples were collected from an 11 year-old BRC in Charlotte, NC, and analyzed for the accumulation and spatial distribution of zinc, copper, and phosphorus. Pollutant distribution varied significantly with respect to depth and ordinate distance from the BRC inlet. Zinc concentrations (0.9-228.6 mg kg -1 soil) exceeded environmental thresholds and phosphorus concentrations (5.1-173.3 mg kg -1 soil) increased from initial levels by a factor of seven; however, notable accumulation was restricted to the BRC forebay. Maximum zinc and copper concentrations in soil media did not exceed 1% of mandatory cleanup levels and with regular maintenance of the forebay, the effective life of BRC media should exceed the life of the developments they treat. Copyright © 2016 Elsevier Ltd. All rights reserved.

Salivary analytes in patients with oral squamous cell carcinoma.

PubMed

Fuchs, Petra Nola; Rogić, Dunja; Vidović-Juras, Danica; Susić, Mato; Milenović, Aleksandar; Brailo, Vlaho; Boras, Vanja Vucićević

2011-06-01

Literature data indicates that measurement of certain salivary constituents might serve as a useful diagnostic/prognostic tool in the patients with oral squamous cell carcinoma (OSCC). In 24 patients with OSCC (60 +/- 2.5 yrs) and in 24 controls (24 +/- 3.7 yrs) we have determined levels of salivary magnesium, calcium, copper, chloride, phosphate, potassium, sodium, total proteins and amylase. Sodium, potassium and chloride were determined by indirect potentiometry whereas copper, magnesium and phosphate were determined by atomic absorption spectrophotometry. Total proteins were determined by pyrogalol colorimetric method. Amylase levels were determined by continued colorimetric method. Statistical analysis was performed by use of chi2 test and Spearman's correlation test. The results of this study indicate that the concentrations of sodium and chloride were significantly elevated in patients with OSCC when compared to the controls. However, level of total protein was significantly decreased when compared to the healthy controls. Furthermore, there was a negative correlation between alcohol consumption and total protein concentration in patients with oral carcinoma. We might conclude that in patients with OSCC increased salivary sodium and chloride might reflect their overall dehydration status due to alcohol consumption rather than consequence of OSCC itself.

Preliminary report on the Apex and Paymaster mines, Washington County, Utah

USGS Publications Warehouse

Kinkel, Arthur R.

1951-01-01

The Apex and Paymaster mines in the Tutsagubet mining district, 25 miles southwest of St. George, Utah, are at an elevation of about 5,000 feet in the Beaver Dam Mountains. The ore was deposited in a steeply dipping fault zone which cuts a thick series of gently dipping limestones of Pennsylvanian age with minor interbedded shales and sandstones. The ore now consists primarily of copper oxides, but is reported to contain small quantities of lead and sine oxides. Complete oxidation extends to the 1,400 level of the Apex mine, the deepest level in this mine. Lead oxides are reported to have been more plentiful in the workings near surface, but the stoped area is now caved to the 1,330 level. The ore bodies probably formed largely as a filling in the fault fissure, and in crushed zones along the fault, with only minor replacement extending for short distances along the bedding. The sulfides oxidized essentially in place and migration of the oxidized copper ores is believed to be limited to a few feet. Additional exploration below the known ore shoots in the Apex and Paymaster mines and along the fissure between the two mines may disclose new ore bodies.

Toxicity of sulfadiazine and copper and their interaction to wheat (Triticum aestivum L.) seedlings.

PubMed

Xu, Yonggang; Yu, Wantai; Ma, Qiang; Zhou, Hua; Jiang, Chunming

2017-08-01

A pot experiment was carried out to investigate the single and combined effect of different concentrations of sulfadiazine (SDZ) (1 and 10mgkg -1 ) and copper (Cu) (20 and 200mgkg -1 ) stresses on growth, hydrogen peroxide (H 2 O 2 ), malondialdehyde (MDA), antioxidant enzyme activities of wheat seedlings and their accumulation. High SDZ or Cu level significantly inhibited the growth of wheat seedlings, but the emergence rate was only inhibited by high SDZ level. The presence of Cu reduced the accumulation of SDZ, whereas the effect of SDZ on the accumulation of Cu depended on their concentrations. Low Cu level significantly increased the chlorophyll content, while high Cu level or both SDZ concentrations resulted in a significant decrease in the chlorophyll content as compared to the control. Additionally, H 2 O 2 and MDA contents increased with the elevated SDZ or Cu level. The activities of superoxide dismutase, peroxidase and catalase were also stimulated by SDZ or Cu except for the aerial part treated by low Cu level and root treated by high SDZ level. The joint toxicity data showed that the toxicity of SDZ to wheat seedlings was generally alleviated by the presence of Cu, whereas the combined toxicity of SDZ and Cu was larger than equivalent Cu alone. Copyright © 2017. Published by Elsevier Inc.

[Use of copper oxide wire particles (Copinox) for the prevention of congenital copper deficiency in a herd of German Improved Fawn breed of goat].

PubMed

Winter, P; Hochsteiner, W; Chizzola, R

2004-10-01

In a herd of German Improved Fawn breed of goat in the year 2000 neonatal kid losses due to congenital copper deficiencies were observed. To clarify the problems and to prevent losses in the next breeding season serum copper levels of 10 dams and four control Boer goats were investigated at four time points during one year. Additionally ten kids of the following year were sampled and the serum copper levels were studied. Immediatly after parturition and 8 weeks later the dams showed low serum copper levels (10.4 +/- 11.1 micromol/l, 5.7 +/- 2.9 micromol/l resp.). At the end of the pasture season an increase of serum copper could be measured (19.3 +/- 16.0 micromol/l). To prevent enzootic ataxia due to congenital copper deficiency, the dams were treated with copper oxide wire particles in the next late gestation. At this time point serum copper concentrations started to decrease (18.5 +/- 8.4 micromol/l). The re-examination 3 month later demonstrated an increase of the serum mean copper concentrations up to 23.4 micromol/l in the dams and to 16.2 micromol/l in the kids. The serum copper levels were significantly higher compared to the levels the year before. Big variation of the serum copper levels in the control Boer goats occurred during the year, but no clinical symptoms of copper deficiency could be observed. The copper levels in the grass and soil samples were 6.8 mg/kg and 0.2 mg/kg dry substance, respectively. A secondary copper deficiency based on cadmium could be excluded through the low levels of soil samples. The contents of sulphur and molybdenum were not determined. The results indicate that the German Improved Fawn breed of goats suffered from a primary copper deficiency due to the inefficient mineral supplementation. The administration of Copinox in the last third of the gestation leads to a continious raising of the copper concentrations in the serum and is suited to prevent ataxia due to congential copper deficiency in neonatal kids.

Copper deficiency in Tule Elk at Point Reyes, California

USGS Publications Warehouse

Gogan, Peter J.P.; Jessup, David A.; Akeson, Mark

1989-01-01

Tule elk (Cervus elaphus nannodes) reintroduced to Point Reyes, Calif., in 1978 exhibited gross signs of copper deficiency by June 1979. Copper levels in liver (x=5.9 ppm) and serum (0.42 ppm) of elk in Point Reyes were below levels in adult tule elk from other locations in California (liver, x=80 ppm; serum, x=1.4 ppm). These levels were consistent with documented copper deficiencies in wild and domestic ruminants. Copper serum levels increased in response to copper enriched dietary supplements and declined after the elk stopped eating the supplements. Analysis of plant and soil samples showed both are deficient in copper and normal in molybdenum and sulfur-sulfates. Deficiency in plants and soils at Point Reyes are probably due to low copper levels in the underlying granitic parent material.

Chemical Data for Rock, Sediment, Biological, Precipitate, and Water Samples from Abandoned Copper Mines in Prince William Sound, Alaska

USGS Publications Warehouse

Koski, Randolph A.; Munk, LeeAnn

2007-01-01

In the early 20th century, approximately 6 million metric tons of copper ore were mined from numerous deposits located along the shorelines of fjords and islands in Prince William Sound, Alaska. At the Beatson, Ellamar, and Threeman mine sites (fig. 1), rocks containing Fe, Cu, Zn, and Pb sulfide minerals are exposed to chemical weathering in abandoned mine workings and remnant waste piles that extend into the littoral zone. Field investigations in 2003 and 2005 as well as analytical data for rock, sediment, precipitate, water, and biological samples reveal that the oxidation of sulfides at these sites is resulting in the generation of acid mine drainage and the transport of metals into the marine environment (Koski and others, 2008; Stillings and others, 2008). At the Ellamar and Threeman sites, plumes of acidic and metal-enriched water are flowing through beach gravels into the shallow offshore environment. Interstitial water samples collected from beach sediment at Ellamar have low pH levels (to ~3) and high concentrations of metals including iron, copper, zinc, cobalt, lead, and mercury. The abundant precipitation of the iron sulfate mineral jarosite in the Ellamar gravels also signifies a low-pH environment. At the Beatson mine site (the largest copper mine in the region) seeps containing iron-rich microbial precipitates drain into the intertidal zone below mine dumps (Foster and others, 2008). A stream flowing down to the shoreline from underground mine workings at Beatson has near-neutral pH, but elevated levels of zinc, copper, and lead (Stillings and others, 2008). Offshore sediment samples at Beatson are enriched in these metals. Preliminary chemical data for tissue from marine mussels collected near the Ellamar, Threeman, and Beatson sites reveal elevated levels of copper, zinc, and lead compared to tissue in mussels from other locations in Prince William Sound (Koski and others, 2008). Three papers presenting results of this ongoing investigation of sulfide oxidation in Prince William Sound are in press. Koski and others (2008) provide an overview of rock alteration, surface water chemistry, and the distribution of metals at the Ellamar, Threeman, and Beatson mine sites. Based on a 60-day, stream-discharge experiment at Beatson in 2005, Stillings and others (2008) analyze changes in water chemistry during storm events and the flux of metals to the shoreline. Foster and others (2008) investigate the biomass and diversity of microbial communities present in surface waters (streams, seeps, pore waters) using fatty acid methyl ester (FAMES) data and principal component analysis. The publications cited above contain a subset of the total chemical data for rock, sediment, biological, precipitate, and water samples collected from the three mine sites in 2003 and 2005. The purpose of this report is the presentation of complete chemical data sets for all samples collected during the two field periods of fieldwork. Data for a small number of samples collected at two other mines (Schlosser and Fidalgo, fig. 1), visited in 2003, are also included in the tables.

Chemical Data for Rock, Sediment, Biological, Precipitate, and Water Samples from Abandoned Copper Mines in Prince William Sound, Alaska

USGS Publications Warehouse

Koski, Randolph A.; Munk, LeeAnn

2007-01-01

Introduction In the early 20th century, approximately 6 million metric tons of copper ore were mined from numerous deposits located along the shorelines of fjords and islands in Prince William Sound, Alaska. At the Beatson, Ellamar, and Threeman mine sites (fig. 1), rocks containing Fe, Cu, Zn, and Pb sulfide minerals are exposed to chemical weathering in abandoned mine workings and remnant waste piles that extend into the littoral zone. Field investigations in 2003 and 2005 as well as analytical data for rock, sediment, precipitate, water, and biological samples reveal that the oxidation of sulfides at these sites is resulting in the generation of acid mine drainage and the transport of metals into the marine environment (Koski and others, 2008; Stillings and others, 2008). At the Ellamar and Threeman sites, plumes of acidic and metal-enriched water are flowing through beach gravels into the shallow offshore environment. Interstitial water samples collected from beach sediment at Ellamar have low pH levels (to ~3) and high concentrations of metals including iron, copper, zinc, cobalt, lead, and mercury. The abundant precipitation of the iron sulfate mineral jarosite in the Ellamar gravels also signifies a low-pH environment. At the Beatson mine site (the largest copper mine in the region) seeps containing iron-rich microbial precipitates drain into the intertidal zone below mine dumps (Foster and others, 2008). A stream flowing down to the shoreline from underground mine workings at Beatson has near-neutral pH, but elevated levels of zinc, copper, and lead (Stillings and others, 2008). Offshore sediment samples at Beatson are enriched in these metals. Preliminary chemical data for tissue from marine mussels collected near the Ellamar, Threeman, and Beatson sites reveal elevated levels of copper, zinc, and lead compared to tissue in mussels from other locations in Prince William Sound (Koski and others, 2008). Three papers presenting results of this ongoing investigation of sulfide oxidation in Prince William Sound are in press. Koski and others (2008) provide an overview of rock alteration, surface water chemistry, and the distribution of metals at the Ellamar, Threeman, and Beatson mine sites. Based on a 60-day, stream-discharge experiment at Beatson in 2005, Stillings and others (2008) analyze changes in water chemistry during storm events and the flux of metals to the shoreline. Foster and others (2008) investigate the biomass and diversity of microbial communities present in surface waters (streams, seeps, pore waters) using fatty acid methyl ester (FAMES) data and principal component analysis. The publications cited above contain a subset of the total chemical data for rock, sediment, biological, precipitate, and water samples collected from the three mine sites in 2003 and 2005. The purpose of this report is the presentation of complete chemical data sets for all samples collected during the two field periods of fieldwork. Data for a small number of samples collected at two other mines (Schlosser and Fidalgo, fig. 1), visited in 2003, are also included in the tables.

Iodinated chlorin p6 copper complex induces anti-proliferative effect in oral cancer cells through elevation of intracellular reactive oxygen species.

PubMed

Sarbadhikary, Paromita; Dube, Alok

2017-11-01

We investigated the anticancer chemotoxicity of previously reported iodinated chlorin p 6 copper complex (ICp 6 -Cu), a novel chlorophyll derivative in which copper is attached to the side chain carboxylate groups via coordination. Human oral carcinoma cells NT8e, 4451 and the non-cancerous keratinocyte HaCaT cells were treated with ICp 6 -Cu for 48 h in dark and cell viability, proliferation and morphological alterations were examined. ICp 6 -Cu showed pronounced cytotoxicity in cancer cells with IC 50 ∼40 μM, whereas, the viability of HaCaT cells was not affected. Cell proliferation assay revealed that ICp 6 -Cu at IC 50 concentration led to complete inhibition of cell proliferation in both the cell lines. Cell morphology studied by confocal microscopy showed absence of cell death via necrosis or apoptosis. Instead, the treated cells displayed distinct features of non-apoptotic death such as highly vacuolated cytoplasm, lysosomal membrane permeabilization and damage to cytoskeleton F-actin filaments. In addition, ICp 6 -Cu treatment led to time dependent increase in the intracellular level of reactive oxygen species (ROS) and the cytotoxicity of ICp 6 -Cu was significantly inhibited by pre-treatment of cells with antioxidants (glutathione and trolox). These findings revealed that ICp 6 -Cu is a potent chemotoxic agent which can induce cytotoxic effect in cancer cells through elevation of intracellular ROS. It is suggested that ICp 6 -Cu may provide tumor selective chemotoxicity by exploiting difference of redox environment in normal and cancer cells. Copyright © 2017 Elsevier B.V. All rights reserved.

A 24 h investigation of the hydrogeochemistry of baseflow and stormwater in an urban area impacted by mining: Butte, Montana

USGS Publications Warehouse

Gammons, Christopher H.; Shope, Christopher L.; Duaime, Terence E.

2005-01-01

Changes in water quality during a storm event were continuously monitored over a 24 h period at a single location along an urban stormwater drain in Butte, Montana. The Butte Metro Storm Drain (MSD) collects groundwater baseflow and stormwater draining Butte Hill, a densely populated site that has been severely impacted by 130 years of mining, milling, and smelting of copper-rich, polymetallic mineral deposits. On the afternoon of 26 June 2002, a heavy thunderstorm caused streamflow in the MSD to increase 100-fold, from 0·2 ft3 s−1 to more than 20 ft3 s−1. Hourly discharge and water quality data were collected before, during, and following the storm. The most significant finding was that the calculated loads (grams per hour) of both dissolved and particulate copper passing down the MSD increased more than 100-fold in the first hour following the storm, and remained elevated over baseline conditions for the remainder of the study period. Other metals, such as zinc, cadmium, and manganese, showed a decrease in load from pre-storm to post-storm conditions. In addition to the large flush of copper, loads of soluble phosphorus increased during the storm, whereas dissolved oxygen dropped to low levels (<2 mg l−1). These results show that infrequent storm events in Butte have the potential to generate large volumes of runoff that exceed Montana water quality standards for acute exposure of aquatic life to copper, as well as depressed levels of dissolved oxygen. This study has important implications to ongoing reclamation activities in the upper Clark Fork Superfund site, particularly with respect to management of storm flow, and may be applicable to other watersheds impacted by mining activities.

Electroencephalographic Fractal Dimension in Healthy Ageing and Alzheimer’s Disease

PubMed Central

Cottone, Carlo; Cancelli, Andrea; Rossini, Paolo Maria; Tecchio, Franca

2016-01-01

Brain activity is complex; a reflection of its structural and functional organization. Among other measures of complexity, the fractal dimension is emerging as being sensitive to neuronal damage secondary to neurological and psychiatric diseases. Here, we calculated Higuchi’s fractal dimension (HFD) in resting-state eyes-closed electroencephalography (EEG) recordings from 41 healthy controls (age: 20–89 years) and 67 Alzheimer’s Disease (AD) patients (age: 50–88 years), to investigate whether HFD is sensitive to brain activity changes typical in healthy aging and in AD. Additionally, we considered whether AD-accelerating effects of the copper fraction not bound to ceruloplasmin (also called “free” copper) are reflected in HFD fluctuations. The HFD measure showed an inverted U-shaped relationship with age in healthy people (R2 = .575, p < .001). Onset of HFD decline appeared around the age of 60, and was most evident in central-parietal regions. In this region, HFD decreased with aging stronger in the right than in the left hemisphere (p = .006). AD patients demonstrated reduced HFD compared to age- and education-matched healthy controls, especially in temporal-occipital regions. This was associated with decreasing cognitive status as assessed by mini-mental state examination, and with higher levels of non-ceruloplasmin copper. Taken together, our findings show that resting-state EEG complexity increases from youth to maturity and declines in healthy, aging individuals. In AD, brain activity complexity is further reduced in correlation with cognitive impairment. In addition, elevated levels of non-ceruloplasmin copper appear to accelerate the reduction of neural activity complexity. Overall, HDF appears to be a proper indicator for monitoring EEG-derived brain activity complexity in healthy and pathological aging. PMID:26872349

Recovery of metal values from copper slag and reuse of residual secondary slag.

PubMed

Sarfo, Prince; Das, Avimanyu; Wyss, Gary; Young, Courtney

2017-12-01

Resource and environmental factors have become major forces in mining and metallurgy sectors driving research for sustainability purposes. The concept of zero-waste processing has been gaining ground readily. The scant availability of high quality raw materials has forced the researchers to shift their focus to recycling while the exceedingly stringent environmental regulations have forced researchers to explore new frontiers of minimizing/eliminating waste generation. The present work is aimed at addressing both aspects by employing recycling to generate wealth from copper slag and producing utilizable materials at the same time thus restoring the ecosystem. Copper slag was characterized and processed. The pyro-metallurgical processing prospects to generate utilizable materials were arrived at through rigorous thermodynamic analysis. Carbothermal reduction at elevated temperature (near 1440°C) helped recover a majority of the metal values (e.g., Fe, Cu and Mo) into the iron-rich alloy product which can be a feed material for steel making. On the other hand, the non-metallic residue, the secondary slag, can be used in the glass and ceramic industries. Reduction time and temperature and carbon content were shown to be the most important process variables for the reaction which were optimized to identify the most favored operating regime that maximizes the metal recovery and simultaneously maximizes the hardness of the secondary slag and minimizes its density, the two major criteria for the secondary slag product to be utilizable. The flux addition level was shown to have relatively less impact on the process performance if these are maintained at an adequate level. The work established that the copper slag, a waste material, can be successfully processed to generate reusable products through pyrometallurgical processing. Copyright © 2017 Elsevier Ltd. All rights reserved.

ESD coating of copper with TiC and TiB2 based ceramic matrix composites

NASA Astrophysics Data System (ADS)

Talas, S.; Mertgenç, E.; Gökçe, B.

2016-08-01

In automotive industry, the spot welding is a general practice to join smaller sections of a car. This welding is specifically carried out in short time and in an elevated number with certain pressure applied on copper electrodes. In addition, copper electrodes are expected to endure against cyclic mechanical pressure and temperature that is released during the passage of the current. The deformation and oxidation behaviour of copper electrodes during service appear with increasing temperature of medium and they also need to be cleaned and cooled or replaced for the continuation of joining process. The coating of copper electrodes with ceramic matrix composites can provide alternative excellent high temperature strength and ensures both economic and efficient use of resources. This study shows that the ESD coating of copper electrodes with a continuous film of ceramic phase ensures an improved resistance to thermal effects during the service and the change in content of film may be critical for cyclic alloying.

Low Hepatic Tissue Copper in Pediatric Nonalcoholic Fatty Liver Disease.

PubMed

Mendoza, Michael; Caltharp, Shelley; Song, Ming; Collin, Lindsay; Konomi, Juna V; McClain, Craig J; Vos, Miriam B

2017-07-01

Animal models and studies in adults have demonstrated that copper restriction increases severity of liver injury in nonalcoholic fatty liver disease (NAFLD). This has not been studied in children. We aimed to determine if lower tissue copper is associated with increased NAFLD severity in children. This was a retrospective study of pediatric patients who had a liver biopsy including a hepatic copper quantitation. The primary outcome compared hepatic copper concentration in NAFLD versus non-NAFLD. Secondary outcomes compared hepatic copper levels against steatosis, fibrosis, lobular inflammation, balloon degeneration, and NAFLD activity score (NAS). The study analysis included 150 pediatric subjects (102 with NAFLD and 48 non-NAFLD). After adjusting for age, body mass index z score, gamma glutamyl transferase, alanine aminotransferase, and total bilirubin, NAFLD subjects had lower levels of hepatic copper than non-NAFLD (P = 0.005). In addition, tissue copper concentration decreased as steatosis severity increased (P < 0.001). Copper levels were not associated with degree of fibrosis, lobular inflammation, portal inflammation, or balloon degeneration. In this cohort of pediatric subjects with NAFLD, we observed decreased tissue copper levels in subjects with NAFLD when compared with non-NAFLD subjects. In addition, tissue copper levels were lower in subjects with nonalcoholic steatohepatitis, a more severe form of the disease, when compared with steatosis alone. Further studies are needed to explore the relationship between copper levels and NAFLD progression.

Screening for Wilson disease in acute liver failure: a comparison of currently available diagnostic tests.

PubMed

Korman, Jessica D; Volenberg, Irene; Balko, Jody; Webster, Joe; Schiodt, Frank V; Squires, Robert H; Fontana, Robert J; Lee, William M; Schilsky, Michael L

2008-10-01

Acute liver failure (ALF) due to Wilson disease (WD) is invariably fatal without emergency liver transplantation. Therefore, rapid diagnosis of WD should aid prompt transplant listing. To identify the best method for diagnosis of ALF due to WD (ALF-WD), data and serum were collected from 140 ALF patients (16 with WD), 29 with other chronic liver diseases and 17 with treated chronic WD. Ceruloplasmin (Cp) was measured by both oxidase activity and nephelometry and serum copper levels by atomic absorption spectroscopy. In patients with ALF, a serum Cp <20 mg/dL by the oxidase method provided a diagnostic sensitivity of 21% and specificity of 84% while, by nephelometry, a sensitivity of 56% and specificity of 63%. Serum copper levels exceeded 200 microg/dL in all ALF-WD patients measured (13/16), but were also elevated in non-WD ALF. An alkaline phosphatase (AP) to total bilirubin (TB) ratio <4 yielded a sensitivity of 94%, specificity of 96%, and a likelihood ratio of 23 for diagnosing fulminant WD. In addition, an AST:ALT ratio >2.2 yielded a sensitivity of 94%, a specificity of 86%, and a likelihood ratio of 7 for diagnosing fulminant WD. Combining the tests provided a diagnostic sensitivity and specificity of 100%. Conventional WD testing utilizing serum ceruloplasmin and/or serum copper levels are less sensitive and specific in identifying patients with ALF-WD than other available tests. More readily available laboratory tests including alkaline phosphatase, bilirubin and serum aminotransferases by contrast provides the most rapid and accurate method for diagnosis of ALF due to WD.

Detection of Genetically Altered Copper Levels in Drosophila Tissues by Synchrotron X-Ray Fluorescence Microscopy

PubMed Central

Lye, Jessica C.; Hwang, Joab E. C.; Paterson, David; de Jonge, Martin D.; Howard, Daryl L.; Burke, Richard

2011-01-01

Tissue-specific manipulation of known copper transport genes in Drosophila tissues results in phenotypes that are presumably due to an alteration in copper levels in the targeted cells. However direct confirmation of this has to date been technically challenging. Measures of cellular copper content such as expression levels of copper-responsive genes or cuproenzyme activity levels, while useful, are indirect. First-generation copper-sensitive fluorophores show promise but currently lack the sensitivity required to detect subtle changes in copper levels. Moreover such techniques do not provide information regarding other relevant biometals such as zinc or iron. Traditional techniques for measuring elemental composition such as inductively coupled plasma mass spectroscopy are not sensitive enough for use with the small tissue amounts available in Drosophila research. Here we present synchrotron x-ray fluorescence microscopy analysis of two different Drosophila tissues, the larval wing imaginal disc, and sectioned adult fly heads and show that this technique can be used to detect changes in tissue copper levels caused by targeted manipulation of known copper homeostasis genes. PMID:22053217

Second-Generation Difluorinated Cyclooctynes for Copper-Free Click Chemistry

PubMed Central

2008-01-01

The 1,3-dipolar cycloaddition of azides and activated alkynes has been used for site-selective labeling of biomolecules in vitro and in vivo. While copper catalysis has been widely employed to activate terminal alkynes for [3 + 2] cycloaddition, this method, often termed “click chemistry”, is currently incompatible with living systems because of the toxicity of the metal. We recently reported a difluorinated cyclooctyne (DIFO) reagent that rapidly reacts with azides in living cells without the need for copper catalysis. Here we report a novel class of DIFO reagents for copper-free click chemistry that are considerably more synthetically tractable. The new analogues maintained the same elevated rates of [3 + 2] cycloaddition as the parent compound and were used for imaging glycans on live cells. These second-generation DIFO reagents should expand the use of copper-free click chemistry in the hands of biologists. PMID:18680289

Reaction layer formation at the graphite/copper-chromium alloy interface

NASA Technical Reports Server (NTRS)

Devincent, Sandra M.; Michal, Gary M.

1992-01-01

Sessile drop tests were used to obtain information about copper chromium alloys that suitably wet graphite. Characterization of graphite/copper-chromium alloy interfaces subjected to elevated temperatures were conducted using scanning electron micrography, energy dispersive spectroscopy, auger electron spectroscopy, and x ray diffraction analyses. These analyses indicate that during sessile drop tests conducted at 1130 C for one hour, copper alloys containing greater than 0.98 percent chromium form continuous reaction layers of approximately 10 micron thickness. The reaction layers adhere to the graphite surface. The copper wets the reaction layer to form a contact angle of 60 degrees or less. X ray diffraction results indicate that the reaction layer is chromium carbide. The kinetics of reaction layer formation were modelled in terms of bulk diffusion mechanisms. Reaction layer thickness is controlled initially by the diffusion of Cr out of Cu alloy and later by the diffusion of C through chromium carbide.

Second-generation difluorinated cyclooctynes for copper-free click chemistry.

PubMed

Codelli, Julian A; Baskin, Jeremy M; Agard, Nicholas J; Bertozzi, Carolyn R

2008-08-27

The 1,3-dipolar cycloaddition of azides and activated alkynes has been used for site-selective labeling of biomolecules in vitro and in vivo. While copper catalysis has been widely employed to activate terminal alkynes for [3 + 2] cycloaddition, this method, often termed "click chemistry", is currently incompatible with living systems because of the toxicity of the metal. We recently reported a difluorinated cyclooctyne (DIFO) reagent that rapidly reacts with azides in living cells without the need for copper catalysis. Here we report a novel class of DIFO reagents for copper-free click chemistry that are considerably more synthetically tractable. The new analogues maintained the same elevated rates of [3 + 2] cycloaddition as the parent compound and were used for imaging glycans on live cells. These second-generation DIFO reagents should expand the use of copper-free click chemistry in the hands of biologists.

Reaction layer formation at the graphite/copper-chromium alloy interface

NASA Technical Reports Server (NTRS)

Devincent, Sandra M.; Michal, Gary M.

1993-01-01

Sessile drop tests were used to obtain information about copper chromium alloys that suitably wet graphite. Characterization of graphite/copper-chromium alloy interfaces subjected to elevated temperatures were conducted using scanning electron micrography, energy dispersive spectroscopy, Auger electron spectroscopy, and X-ray diffraction analyses. These analyses indicate that during sessile drop tests conducted at 1130 C for one hour, copper alloys containing greater than 0.98 percent chromium form continuous reaction layers of approximately 10 micron thickness. The reaction layers adhere to the graphite surface. The copper wets the reaction layer to form a contact angle of 60 degrees or less. X-ray diffraction results indicate that the reaction layer is chromium carbide. The kinetics of reaction layer formation were modelled in terms of bulk diffusion mechanisms. Reaction layer thickness is controlled initially by the diffusion of Cr out of Cu alloy and later by the diffusion of C through chromium carbide.

Copper recovery and cyanide oxidation by electrowinning from a spent copper-cyanide electroplating electrolyte.

PubMed

Dutra, A J B; Rocha, G P; Pombo, F R

2008-04-01

Copper-cyanide bleed streams arise from contaminated baths from industrial electroplating processes due to the buildup of impurities during continuous operation. These streams present an elevated concentration of carbonate, cyanide and copper, constituting a heavy hazard, which has to be treated for cyanide destruction and heavy metals removal, according to the local environmental laws. In the Brazilian Mint, bleed streams are treated with sodium hypochlorite, to destroy cyanide and precipitate copper hydroxide, a solid hazardous waste that has to be disposed properly in a landfill or treated for metal recovery. In this paper, a laboratory-scale electrolytic cell was developed to remove the copper from the bleed stream of the electroplating unit of the Brazilian Mint, permitting its reutilization in the plant and decreasing the amount of sludge to waste. Under favorable conditions copper recoveries around 99.9% were achieved, with an energy consumption of about 11 kWh/kg, after a 5-h electrolysis of a bath containing copper and total cyanide concentrations of 26 and 27 g/L, respectively. Additionally, a substantial reduction of the cyanide concentration was also achieved, decreasing the pollution load and final treatment costs.

Data on surface-water, streambed-interstitial water, and bed-sediment quality for selected locations in the small arms impact area of central Fort Gordon, Georgia, September 4-6, 2001

USGS Publications Warehouse

Priest, Sheryln; Stamey, Timothy C.; Lawrence, Stephen J.

2002-01-01

In September 2001, the U.S. Geological Survey, in cooperation with the Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon (U.S. Department of the Army), conducted a chemical assessment of surface water, streambed-interstitial water, and bed sediments within the small arms impact area of Fort Gordon Military Installation. The study was conducted in support of the development of an Integrated Natural Resources Management Plan (INRMP) for Fort Gordon, Georgia. An effective INRMP ensures that natural resources conservation measures and U.S. Army activities on the military base are integrated and consistent with Federal requirements to manage military installations on an ecosystem basis. Filtered water samples were collected from five sites along South Prong Creek and three sites along Marcum Branch Creek for chemical analyses of major ions, nutrients, and selected trace elements. On-site measurements of pH, temperature, specific conductance, and dissolved oxygen were made at the eight sites. Filtered water collected showed varying concentrations in both surface- and streambed-interstitial water. Bed-sediment samples collected from South Prong Creek contain elevated levels of arsenic, barium, beryllium, cadmium, chromium, cobalt, copper, iron, lead, manganese, nickel, selenium, vanadium, and total organic carbon relative to previous concentrations (McConnell and others, 2000). Bed-sediment samples collected from Marcum Branch Creek contain elevated levels of beryllium, copper, lead, manganese, mercury, selenium, and total organic carbon relative to previous concentrations (McConnell and others, 2000).

Estimating Dermal Transfer of Copper Particles from the ...

EPA Pesticide Factsheets

Lumber pressure-treated with micronized copper was examined for the release of copper and copper micro/nanoparticles using a surface wipe method to simulate dermal transfer. In 2003, the wood industry began replacing CCA treated lumber products for residential use with copper based formulations. Micronized copper (nano to micron sized particles) has become the preferred treatment formulation. There is a lack of information on the release of copper, the fate of the particles during dermal contact, and the copper exposure level to children from hand-to-mouth transfer. For the current study, three treated lumber products, two micronized copper and one ionic copper, were purchased from commercial retailers. The boards were left to weather outdoors for approximately 1 year. Over the year time period, hand wipe samples were collected periodically to determine copper transfer from the wood surfaces. The two micronized formulations and the ionic formulation released similar levels of total copper. The amount of copper released was high initially, but decreased to a constant level (~1.5 mg m-2) after the first month of outdoor exposure. Copper particles were identified on the sampling cloths during the first two months of the experiment, after which the levels of copper were insufficient to collect interpretable data. After 1 month, the particles exhibited minimal changes in shape and size. At the end of 2-months, significant deterioration of the particles was

Geomorphology and river dynamics of the lower Copper River, Alaska

USGS Publications Warehouse

Brabets, Timothy P.; Conaway, Jeffrey S.

2009-01-01

Located in south-central Alaska, the Copper River drains an area of more than 24,000 square miles. The average annual flow of the river near its mouth is 63,600 cubic feet per second, but is highly variable between winter and summer. In the winter, flow averages approximately 11,700 cubic feet per second, and in the summer, due to snowmelt, rainfall, and glacial melt, flow averages approximately 113,000 cubic feet per second, an order of magnitude higher. About 15 miles upstream of its mouth, the Copper River flows past the face of Childs Glacier and enters a large, broad, delta. The Copper River Highway traverses this flood plain, and in 2008, 11 bridges were located along this section of the highway. The bridges cross several parts of the Copper River and in recent years, the changing course of the river has seriously damaged some of the bridges.Analysis of aerial photography from 1991, 1996, 2002, 2006, and 2007 indicates the eastward migration of a channel of the Copper River that has resulted in damage to the Copper River Highway near Mile 43.5. Migration of another channel in the flood plain has resulted in damage to the approach of Bridge 339. As a verification of channel change, flow measurements were made at bridges along the Copper River Highway in 2005–07. Analysis of the flow measurements indicate that the total flow of the Copper River has shifted from approximately 50 percent passing through the bridges at Mile 27, near the western edge of the flood plain, and 50 percent passing through the bridges at Mile 36–37 to approximately 5 percent passing through the bridges at Mile 27 and 95 percent through the bridges at Mile 36–37 during average flow periods.The U.S. Geological Survey’s Multi-Dimensional Surface-Water Modeling System was used to simulate water-surface elevation and velocity, and to compute bed shear stress at two areas where the Copper River is affecting the Copper River Highway. After calibration, the model was used to examine the effects that betterments, such as guide banks or bridge extensions, would have on flow conditions and to provide sound conceptual information that could help decide if a proposed betterment will work or determine potential problems that need to be addressed for a particular betterment. The ability of the model to simulate these hydraulic conditions was constrained by the accuracy and level of channel geometry detail, which is constantly changing in the lower Copper River.

Characterization of failure processes in tungsten copper composites under fatigue loading conditions

NASA Technical Reports Server (NTRS)

Kim, Yong-Suk; Verrilli, Michael J.; Gabb, Timothy P.

1989-01-01

A fractographic and metallographic investigation was performed on specimens of a tungsten fiber reinforced copper matrix composite (9 vol percent), which had experienced fatigue failures at elevated temperatures. Major failure modes and possible failure mechanisms, with an emphasis placed on characterizing fatigue damage accumulation, were determined. Metallography of specimens fatigued under isothermal cyclic loading suggested that fatigue damage initiates in the matrix. Cracks nucleated within the copper matrix at grain boundaries, and they propagated through cavity coalescence. The growing cracks subsequently interacted with the reinforcing tungsten fibers, producing a localized ductile fiber failure. Examinations of interrupted tests before final failure confirmed the suggested fatigue damage processes.

The insulation of copper wire by the electrostatic coating process

NASA Astrophysics Data System (ADS)

Wells, M. G. H.

1983-06-01

A review of the fluidized bed electrostatic coating process and materials available for application to flat copper conductor has been made. Lengths of wire were rolled and electrostatically coated with two epoxy insulations. Electrical tests were made in air on coated samples at room and elevated temperatures. Compatibility tests in the cooling/lubricating turbine oil at temperatures up to 220 deg. C were also made. Recommendations for additional work are provided.

The Role of Grain Size on Neutron Irradiation Response of Nanocrystalline Copper

PubMed Central

Mohamed, Walid; Miller, Brandon; Porter, Douglas; Murty, Korukonda

2016-01-01

The role of grain size on the developed microstructure and mechanical properties of neutron irradiated nanocrystalline copper was investigated by comparing the radiation response of material to the conventional micrograined counterpart. Nanocrystalline (nc) and micrograined (MG) copper samples were subjected to a range of neutron exposure levels from 0.0034 to 2 dpa. At all damage levels, the response of MG-copper was governed by radiation hardening manifested by an increase in strength with accompanying ductility loss. Conversely, the response of nc-copper to neutron irradiation exhibited a dependence on the damage level. At low damage levels, grain growth was the primary response, with radiation hardening and embrittlement becoming the dominant responses with increasing damage levels. Annealing experiments revealed that grain growth in nc-copper is composed of both thermally-activated and irradiation-induced components. Tensile tests revealed minimal change in the source hardening component of the yield stress in MG-copper, while the source hardening component was found to decrease with increasing radiation exposure in nc-copper. PMID:28773270

Study of oxidative stress biomarkers in chronic obstructive pulmonary disease and their correlation with disease severity in north Indian population cohort

PubMed Central

Bajpai, Jyoti; Prakash, Ved; Kant, Surya; Verma, Ajay Kumar; Srivastava, Anand; Bajaj, Darshan K; Ahmad, MK; Agarwal, Avinash

2017-01-01

Background: Oxidant-antioxidant imbalance forms a prime component in pathogenesis of chronic obstructive pulmonary disease (COPD). Studies of oxidative stress markers in South Asians were sparse. Methods: One hundred and eighty COPD patients and eighty healthy nonsmokers were enrolled in the study. Serum malondialdehyde (MDA) and iron levels were estimated for oxidative stress. Three antioxidant markers evaluated-catalase, superoxide dismutase (SOD), and serum copper. Patients on antioxidant therapy and with sepsis and chronic illness were excluded from the study. Results: The mean age of COPD patients was 59.29 ± 10.3 years. Serum levels of MDA and iron were significantly higher in COPD patients compared to controls (5.21 ± 1.9 vs. 0.71 ± 0.29 nmol MDA/ml, P = 0.0001 and 69.85 ± 85.49 vs. 79.32 ± 24.39 μg/dl, P = 0.0001, respectively). Mean level of all antioxidant enzymes catalase, SOD, and copper were significantly diminished in cases when compared to control population (P = 0.001). Levels of MDA and iron were found to be significantly elevated in higher Global Initiative for Chronic Obstructive Lung Disease (GOLD) classes (III, IV) when compared to lower GOLD Classes (I, II). The levels of serum antioxidants were significantly depleted in higher GOLD grades too. COPD patients who were male and smoked had significantly higher levels of oxidants and depleted antioxidant levels compared to female and nonsmoking compatriots. Serum MDA levels negatively correlated with forced expiratory volume 1 s and forced vital capacity (r = −0.19 and r = −0.21, P ≤ 0.01). The presence of a cough significantly correlated with higher levels of MDA and iron (P = 0.001). The levels of MDA negatively correlated with SOD and catalase levels. Conclusion: Oxidative markers (MDA and iron) are higher whereas antioxidants (catalase, copper, and SOD) are significantly reduced in patients of COPD. Serum MDA levels correlate with lung functions and disease severity. PMID:28671162

Mechanisms of Contact-Mediated Killing of Yeast Cells on Dry Metallic Copper Surfaces▿

PubMed Central

Quaranta, Davide; Krans, Travis; Santo, Christophe Espírito; Elowsky, Christian G.; Domaille, Dylan W.; Chang, Christopher J.; Grass, Gregor

2011-01-01

Surfaces made of copper or its alloys have strong antimicrobial properties against a wide variety of microorganisms. However, the molecular mode of action responsible for the antimicrobial efficacy of metallic copper is not known. Here, we show that dry copper surfaces inactivate Candida albicans and Saccharomyces cerevisiae within minutes in a process called contact-mediated killing. Cellular copper ion homeostasis systems influenced the kinetics of contact-mediated killing in both organisms. Deregulated copper ion uptake through a hyperactive S. cerevisiae Ctr1p (ScCtr1p) copper uptake transporter in Saccharomyces resulted in faster inactivation of mutant cells than of wild-type cells. Similarly, lack of the C. albicans Crp1p (CaCrp1p) copper-efflux P-type ATPase or the metallothionein CaCup1p caused more-rapid killing of Candida mutant cells than of wild-type cells. Candida and Saccharomyces took up large quantities of copper ions as soon as they were in contact with copper surfaces, as indicated by inductively coupled plasma mass spectroscopy (ICP-MS) analysis and by the intracellular copper ion-reporting dye coppersensor-1. Exposure to metallic copper did not cause lethality through genotoxicity, deleterious action on a cell's genetic material, as indicated by a mutation assay with Saccharomyces. Instead, toxicity mediated by metallic copper surfaces targeted membranes in both yeast species. With the use of Live/Dead staining, onset of rapid and extensive cytoplasmic membrane damage was observed in cells from copper surfaces. Fluorescence microscopy using the indicator dye DiSBaC2(3) indicated that cell membranes were depolarized. Also, during contact-mediated killing, vacuoles first became enlarged and then disappeared from the cells. Lastly, in metallic copper-stressed yeasts, oxidative stress in the cytoplasm and in mitochondria was elevated. PMID:21097600

Tolerance and stress response of sclerotiogenic Aspergillus oryzae G15 to copper and lead.

PubMed

Long, Dan-Dan; Fu, Rong-Rong; Han, Jian-Rong

2017-07-01

Aspergillus oryzae G15 was cultured on Czapek yeast extract agar medium containing different concentrations of copper and lead to investigate the mechanisms sustaining metal tolerance. The effects of heavy metals on biomass, metal accumulation, metallothionein (MT), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were evaluated. Cu and Pb treatment remarkably delayed sclerotial maturation and inhibited mycelial growth, indicating the toxic effects of the metals. Cu decreased sclerotial biomass, whereas Pb led to an increase in sclerotial biomass. G15 bioadsorbed most Cu and Pb ions on the cell surface, revealing the involvement of the extracellular mechanism. Cu treatment significantly elevated MT level in mycelia, and Pb treatment at concentrations of 50-100 mg/L also caused an increase in MT content in mycelia. Both metals significantly increased MDA level in sclerotia. The variations in MT and MDA levels revealed the appearance of heavy metal-induced oxidative stress. The activities of SOD, CAT, and POD varied with heavy metal concentrations, which demonstrated that tolerance of G15 to Cu and Pb was associated with an efficient antioxidant defense system. In sum, the santioxidative detoxification system allowed the strain to survive in high concentrations of Cu and Pb. G15 depended mostly on sclerotial differentiation to defend against Pb stress.

Offshore drilling effects in Brazilian SE marine sediments: a meta-analytical approach.

PubMed

Dore, Marina Pereira; Farias, Cássia; Hamacher, Cláudia

2017-01-01

The exploration and production of oil and gas reserves often result to drill cutting accumulations on the seafloor adjacent to drill locations. In this study, the detection of drilling influence on marine sediments was performed by meta-analytical comparison between data from pre- and post-drilling surveys undertaken in offshore Campos Basin, southeast of Brazil. Besides this overall appraisal on the geochemical variables, a multivariate assessment, considering only the post-drilling data, was performed. Among the variables, fines content, carbonates, total organic carbon, barium, chromium, copper, iron, manganese, nickel, lead, vanadium, zinc, and total petroleum hydrocarbons, only barium, copper, and hydrocarbons were related to drilling impacts. In relation to the point of discharge, relative elevated levels in the post-drilling campaigns were observed preferentially up to 500 m in the northeast and southwest directions, associated to the Brazil Current-predominant direction. Other distributed concentrations in the surroundings seem to indicate the dilution and dispersion of drilling waste promoted by meteoceanographic factors.

Molybdenum toxicity and hypocuprosis in ruminants: a review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, G.M.

1978-01-01

Elevated Mo intakes depress Cu availability and may produce a physiological Cu deficiency in ruminants. Total sulfur or sulfate in the ration generally potentiates the effect of Mo. The ratio of Cu to Mo in feed is important regardless of the absolute amount of each. For this reason, and because of the importance of the S content of the diet, it is impossible to define safe dietary limits for Cu and Mo. Physiological Cu deficiencies are produced by four classes of feeds: (1) high Mo, generally above 100 ppM, (2) low Cu:Mo ratio, 2:1 or less, (3) Cu deficiency, belowmore » 5 ppM, and (4) high protein, 20 to 30% protein in fresh forage. The latter situation probably results from higher levels of sulfide produced from sulfur amino acids during rumen fermentation. Copper sulfide is largely unabsorbed. Future instances of hypocuprosis in the US are most likely to occur from marginal copper deficiencies in forages.« less

Copper control of bacterial nitrous oxide emission and its impact on vitamin B12-dependent metabolism

PubMed Central

Sullivan, Matthew J.; Gates, Andrew J.; Appia-Ayme, Corinne; Rowley, Gary; Richardson, David J.

2013-01-01

Global agricultural emissions of the greenhouse gas nitrous oxide (N2O) have increased by around 20% over the last 100 y, but regulation of these emissions and their impact on bacterial cellular metabolism are poorly understood. Denitrifying bacteria convert nitrate in soils to inert di-nitrogen gas (N2) via N2O and the biochemistry of this process has been studied extensively in Paracoccus denitrificans. Here we demonstrate that expression of the gene encoding the nitrous oxide reductase (NosZ), which converts N2O to N2, is regulated in response to the extracellular copper concentration. We show that elevated levels of N2O released as a consequence of decreased cellular NosZ activity lead to the bacterium switching from vitamin B12-dependent to vitamin B12-independent biosynthetic pathways, through the transcriptional modulation of genes controlled by vitamin B12 riboswitches. This inhibitory effect of N2O can be rescued by addition of exogenous vitamin B12. PMID:24248380

Draft genome sequence of chloride-tolerant Leptospirillum ferriphilum Sp-Cl from industrial bioleaching operations in northern Chile.

PubMed

Issotta, Francisco; Galleguillos, Pedro A; Moya-Beltrán, Ana; Davis-Belmar, Carol S; Rautenbach, George; Covarrubias, Paulo C; Acosta, Mauricio; Ossandon, Francisco J; Contador, Yasna; Holmes, David S; Marín-Eliantonio, Sabrina; Quatrini, Raquel; Demergasso, Cecilia

2016-01-01

Leptospirillum ferriphilum Sp-Cl is a Gram negative, thermotolerant, curved, rod-shaped bacterium, isolated from an industrial bioleaching operation in northern Chile, where chalcocite is the major copper mineral and copper hydroxychloride atacamite is present in variable proportions in the ore. This strain has unique features as compared to the other members of the species, namely resistance to elevated concentrations of chloride, sulfate and metals. Basic microbiological features and genomic properties of this biotechnologically relevant strain are described in this work. The 2,475,669 bp draft genome is arranged into 74 scaffolds of 74 contigs. A total of 48 RNA genes and 2,834 protein coding genes were predicted from its annotation; 55 % of these were assigned a putative function. Release of the genome sequence of this strain will provide further understanding of the mechanisms used by acidophilic bacteria to endure high osmotic stress and high chloride levels and of the role of chloride-tolerant iron-oxidizers in industrial bioleaching operations.

Acute phase response and plasma carotenoid concentrations in older women: findings from the nun study.

PubMed

Boosalis, M G; Snowdon, D A; Tully, C L; Gross, M D

1996-01-01

This cross-sectional study investigated whether the acute phase response was associated with suppressed circulating levels of antioxidants in a population of 85 Catholic sisters (nuns) ages 77-99 y. Fasting blood was drawn to determine the presence of an acute phase response, as defined by an elevation in the serum concentration of C-reactive protein. Serum concentrations of albumin, thyroxine-binding prealbumin, zinc, copper, and fibrinogen were determined as were plasma concentrations of carotenoids and alpha tocopherol. Results showed that the presence of an acute phase response was associated with (1) an expected significant decrease in the serum concentrations of albumin (p < 0.001) and thyroxine-binding prealbumin (p < 0.001); (2) an expected significant increase in copper (p < 0.001) and fibrinogen (p = 0.003); and (3) a significant decrease in the plasma concentrations of lycopene (p = 0.03), alpha carotene (p = 0.02), beta carotene (p = 0.02), and total carotenoids (p = 0.01). The acute phase response was associated with decreased plasma levels of the antioxidants lycopene, alpha carotene, and beta carotene. This decrease in circulating antioxidants may further compromise antioxidant status and increase oxidative stress and damage in elders.

A historical case of beaten-copper cranium.

PubMed

Rühli, Frank J; Nicklisch, Nicole; Alt, Kurt W

2007-01-01

The authors present the oldest historical case of a so-called beaten-copper cranium. The typical pattern was identified on a skull from a child, probably a boy, who died at approximately 6 years of age and was buried in a provisional cemetery used during the siege of Hanau, Germany, in 1635 and 1636. Morphological and radiological analyses of the severe digitate impressions ubiquitous on the child's endocranium support the diagnosis of chronically elevated intracranial pressure due to hydrocephalus.

Elemental composition of human semen is associated with motility and genomic sperm defects among older men

PubMed Central

Schmid, Thomas E.; Grant, Patrick G.; Marchetti, Francesco; Weldon, Rosana H.; Eskenazi, Brenda; Wyrobek, Andrew J.

2013-01-01

BACKGROUND Older men tend to have poorer semen quality and are generally at higher risks for infertility and abnormal reproductive outcomes. METHODS We employed proton-induced X-ray emission (PIXE, 3 MeV proton beam) to investigate the concentrations of zinc, copper, calcium, sulfur, chlorine, potassium, titanium, iron and nickel in washed sperm and seminal plasma from non-smoking groups of 10 older men (65–80 years old) and 10 younger men (22–28 years old) who were concurrently assayed for sperm function and genomicly defective sperm. RESULTS The older group showed elevated zinc, copper and calcium in sperm and elevated sulfur in seminal plasma compared with the younger men. The older group also showed reduced motility as well as increased sperm DNA fragmentation, achondroplasia mutations, DNA strand breaks and chromosomal aberrations. Sperm calcium and copper were positively associated with sperm DNA fragmentation (P < 0.03). Seminal sulfur was positively associated with sperm DNA fragmentation and chromosomal aberrations (P < 0.04), and negatively associated with sperm motility (P < 0.05). Sperm calcium was negatively associated with sperm motility, independent of male age (P = 0.01). CONCLUSIONS We identified major differences in elemental concentrations between sperm and seminal plasma and that higher sperm copper, sulfur and calcium are quantitatively associated with poorer semen quality and increased frequencies of genomic sperm defects. PMID:23042799

Supplementation with zinc in rats enhances memory and reverses an age-dependent increase in plasma copper.

PubMed

Sandusky-Beltran, Leslie A; Manchester, Bryce L; McNay, Ewan C

2017-08-30

Zinc and copper are essential trace elements. Dyshomeostasis in these two metals has been observed in Alzheimer's disease, which causes profound cognitive impairment. Insulin therapy has been shown to enhance cognitive performance; however, recent data suggest that this effect may be at least in part due to the inclusion of zinc in the insulin formulation used. Zinc plays a key role in regulation of neuronal glutamate signaling, suggesting a possible link between zinc and memory processes. Consistent with this, zinc deficiency causes cognitive impairments in children. The effect of zinc supplementation on short- and long-term recognition memory, and on spatial working memory, was explored in young and adult male Sprague Dawley rats. After behavioral testing, hippocampal and plasma zinc and copper were measured. Age increased hippocampal zinc and copper, as well as plasma copper, and decreased plasma zinc. An interaction between age and treatment affecting plasma copper was also found, with zinc supplementation reversing elevated plasma copper concentration in adult rats. Zinc supplementation enhanced cognitive performance across tasks. These data support zinc as a plausible therapeutic intervention to ameliorate cognitive impairment in disorders characterized by alterations in zinc and copper, such as Alzheimer's disease. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of short term oral cadmium exposure in rats fed low zinc and low copper diets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Panemangalore, M.; Lee, C.J.; Wilson, K.

1986-03-05

The effects of 0, 0.15 and 5.0 ppm Cd in drinking water was determined in 10 week old F-344 rats fed either control - C (30 ppm Zn + 5 ppm Cu), low Zn - LZn (5 ppm Zn), low copper - LCu (0.5 ppm Cu) and low Zn + low Cu - LZn + LCu (5 ppm Zn + 0.5 ppm Cu) diets for 8 weeks. All groups gained about 9 g/wk and neither the decrease in dietary Zn and Cu levels or Cd exposure altered wt gain or food intake (14 g/day). Liver Zn levels averaged about 19more » mg/g in all groups and were unaffected by either diet or Cd exposure; but metallothionein (MT) concentration increased from 19..mu..g/g to 40 ..mu..g/g in groups exposed to 5.0 ppm Cd and was lower in rats given LZn and LZn + LCu diet (pless than or equal to0.05). In contrast, kidney Zn levels declined in groups fed LZn + LCu diets, but exposure to Cd maintained Zn levels. Kidney MT concentration fell in response to LZn, LCu and LZn + LCu diets, while exposure to 5.0 ppm Cd elevated MT concentration almost 3 fold, however, LZn and LCu diets decreased the extent of MT induction (pless than or equal to0.05). Kidney Zn levels appear to be more susceptible to modulation by dietary Zn and Cu levels, and oral Cd exposure.« less

Copper toxicity in the crab, Scylla serrata, copper levels in tissues and regulation after exposure to a copper-rich medium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arumugam, M.; Ravindranath, M.H.

1987-10-01

In the decapod crustaceans copper is distributed in various tissues. In these animals the tissue copper generally exists in four forms; ionic, bound to proteins, lipids and membrane. In the estuarine crab Scylla serrata, the haemolymph copper exists only in association with proteins, whereas in the hepatopancreas it exists in all the four forms and in gills it exists in all the forms except in combination with lipids. Although food is the major source of copper in decapod crustaceans evidence indicate that copper may be directly obtained from the environment. It was postulated earlier that in Scylla serrata the haemolymphmore » and hepatopancreas may be involved in copper regulation. In the present work the authors have studied the nature and levels of copper in different tissues after exposing the crabs to copper-rich medium. The results indicate the relative importance of various tissues in accumulation an the possible mechanisms of regulation of the environmental copper. Besides, as a pre-requisite for studies of this kind, the toxic levels for different forms of copper were estimated since the form of toxicant is known to influence the toxicity to the decapod crustaceans.« less

Overexpression of copper transporter CTR1 in the brain barrier of North Ronaldsay sheep: implications for the study of neurodegenerative disease.

PubMed

Haywood, S; Vaillant, C

2014-01-01

Age-related regulatory failure of the brain barrier towards the influx of redox metals such as copper and iron may be associated with the pathological changes that characterize dementias such as Alzheimer's diseases (ADs) and amyotrophic lateral sclerosis (ALS). The integrity of the brain barrier to regulate copper in the brain is maintained by the complex interplay of membrane-located transporters, of which copper transporter 1 (CTR1) exerts a defining role. North Ronaldsay (NR) sheep are a primitive breed that have adapted to a copper-deficient environment by an enhanced uptake of the metal, resulting in copper overload in the liver and brain. This study reports that CTR1 is overexpressed in both the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCB) of adult NR sheep when compared with a domesticated breed. The excess copper is stored ultimately in astrocytes as non-injurious copper-metallothionein (MT). NR sheep have apparently retained an immature regulatory setting for CTR1 in the BBB, promoting facilitated copper uptake into the brain. This putative failure of maturation of CTR1 allows insight into the regulatory control of brain copper homeostasis, whereby the BBB and BCB act in concert to sequester excess copper and protect neurons from injury. The elevated copper content of the ageing human brain may derive from a dysregulation of CTR1 at the brain barrier, with a return to the default (immature) setting and implications for neurodegenerative disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

Selected organic compounds and trace elements in streambed sediments and fish tissues, Cook Inlet Basin, Alaska

USGS Publications Warehouse

Frenzel, Steven A.

2000-01-01

Organochlorines, semivolatile organic compounds (SVOCs), and trace elements were investigated in streambed sediments and fish tissues at selected sites in the Cook Inlet Basin, Alaska, during 1998. At most sites, SVOCs and organochlorine compounds were either not detected or detected at very low concentrations. Chester Creek at Arctic Boulevard at Anchorage, which was the only site sampled with a significant degree of development in the watershed, had elevated levels of many SVOCs in streambed sediment. Coring of sediments from two ponds on Chester Creek confirmed the presence of elevated concentrations of a variety of organic compounds. Moose Creek, a stream with extensive coal deposits in its watershed, had low concentrations of numerous SVOCs in streambed sediment. Three sites located in national parks or in a national wildlife refuge had no detectable concentrations of SVOCs. Trace elements were analyzed in both streambed sediments and tissues of slimy sculpin. The two media provided similar evidence for elevated concentrations of cadmium, lead, and zinc at Chester Creek. In this study, 'probable effect levels '(PELs) were determined from sediments finer than 0.063 millimeters, where concentrations tend to be greatest. Arsenic and chromium concentrations exceeded the PEL at eight and six sites respectively. Zinc exceeded the PEL at one site. Cadmium and copper concentrations were smaller than the PEL at all sites. Mercury concentrations in streambed sediments from the Deshka River were near the PEL, and selenium concentrations at that site also appear to be elevated above background levels. At half the sites where slimy sculpin were sampled, selenium concentrations were at levels that may cause adverse effects in some species.

Citric acid assisted phytoremediation of copper by Brassica napus L.

PubMed

Zaheer, Ihsan Elahi; Ali, Shafaqat; Rizwan, Muhammad; Farid, Mujahid; Shakoor, Muhammad Bilal; Gill, Rafaqa Ali; Najeeb, Ullah; Iqbal, Naeem; Ahmad, Rehan

2015-10-01

Use of organic acids for promoting heavy metals phytoextraction is gaining worldwide attention. The present study investigated the influence of citric acid (CA) in enhancing copper (Cu) uptake by Brassica napus L. seedlings. 6 Weeks old B. napus seedlings were exposed to different levels of copper (Cu, 0, 50 and 100µM) alone or with CA (2.5mM) in a nutrient medium for 40 days. Exposure to elevated Cu levels (50 and 100µM) significantly reduced the growth, biomass production, chlorophyll content, gas exchange attributes and soluble proteins of B. napus seedlings. In addition, Cu toxicity increased the production of hydrogen peroxide (H2O2), malondialdehyde (MDA) and electrolyte leakage (EL) in leaf and root tissues of B. napus. Activities of antioxidant enzymes such as guaiacol peroxidase (POD), superoxide dismutase (SOD), catalases (CAT), ascorbate peroxidase (APX) in root and shoot tissues of B. napus were increased in response to lower Cu concentration (50µM) but increased under higher Cu concentration (100µM). Addition of CA into nutrient medium significantly alleviated Cu toxicity effects on B. napus seedlings by improving photosynthetic capacity and ultimately plant growth. Increased activities of antioxidant enzymes in CA-treated plants seems to play a role in capturing of stress-induced reactive oxygen species as was evident from lower level of H2O2, MDA and EL in CA-treated plants. Increasing Cu concentration in the nutrient medium significantly increased Cu concentration in in B. napus tissues. Cu uptake was further increased by CA application. These results suggested that CA might be a useful strategy for increasing phytoextraction of Cu from contaminated soils. Copyright © 2015 Elsevier Inc. All rights reserved.

Heavy-metal contamination on training ranges at the Grafenwoehr Training Area, Germany

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zellmer, S.D.; Schneider, J.F.

1993-05-01

Large quantities of lead and other heavy metals are deposited in the environment of weapons ranges during training exercises. This study was conducted to determine the type, degree, and extent of heavy-metal contamination on selected handgun, rifle, and hand-grenade ranges at Grafenwoehr Training Area, Germany. Soil, vegetation, and surface-water samples were collected and analyzed using the inductively-coupled plasma atomic-emission spectroscopy (ICP-AES) method and the toxic characterization leaching procedure (TCLP). The ICP-AES results show that above-normal levels of lead and copper are in the surface soil at the handgun range, high concentrations of lead and copper are in the berm andmore » soil surface at the rifle range, and elevated levels of cadmium and above-normal concentrations of arsenic, copper, and zinc are present in the surface soil at the hand-grenade range. The TCLP results show that surface soils can be considered hazardous waste because of lead content at the rifle range and because of cadmium concentration at the hand-grenade range. Vegetation at the handgun and rifle ranges has above-normal concentrations of lead. At the hand-grenade range, both vegetation and surface water have high levels of cadmium. A hand-held X-ray fluorescence (XRF) spectrum analyzer was used to measure lead concentrations in soils in a field test of the method. Comparison of XRF readings with ICP-AES results for lead indicate that the accuracy and precision of the hand-held XRF unit must improve before the unit can be used as more than a screening tool. Results of this study show that heavy-metal contamination at all three ranges is limited to the surface soil; heavy metals are not being leached into the soil profile or transported into adjacent areas.« less

Evolution of copper arsenate resistance for enhanced enargite bioleaching using the extreme thermoacidophile Metallosphaera sedula.

PubMed

Ai, Chenbing; McCarthy, Samuel; Liang, Yuting; Rudrappa, Deepak; Qiu, Guanzhou; Blum, Paul

2017-12-01

Adaptive laboratory evolution (ALE) was employed to isolate arsenate and copper cross-resistant strains, from the copper-resistant M. sedula CuR1. The evolved strains, M. sedula ARS50-1 and M. sedula ARS50-2, contained 12 and 13 additional mutations, respectively, relative to M. sedula CuR1. Bioleaching capacity of a defined consortium (consisting of a naturally occurring strain and a genetically engineered copper sensitive strain) was increased by introduction of M. sedula ARS50-2, with 5.31 and 26.29% more copper recovered from enargite at a pulp density (PD) of 1 and 3% (w/v), respectively. M. sedula ARS50-2 arose as the predominant species and modulated the proportions of the other two strains after it had been introduced. Collectively, the higher Cu 2+ resistance trait of M. sedula ARS50-2 resulted in a modulated microbial community structure, and consolidating enargite bioleaching especially at elevated PD.

The Yeast Copper Response Is Regulated by DNA Damage

PubMed Central

Dong, Kangzhen; Addinall, Stephen G.; Lydall, David

2013-01-01

Copper is an essential but potentially toxic redox-active metal, so the levels and distribution of this metal are carefully regulated to ensure that it binds to the correct proteins. Previous studies of copper-dependent transcription in the yeast Saccharomyces cerevisiae have focused on the response of genes to changes in the exogenous levels of copper. We now report that yeast copper genes are regulated in response to the DNA-damaging agents methyl methanesulfonate (MMS) and hydroxyurea by a mechanism(s) that requires the copper-responsive transcription factors Mac1 and AceI, copper superoxide dismutase (Sod1) activity, and the Rad53 checkpoint kinase. Furthermore, in copper-starved yeast, the response of the Rad53 pathway to MMS is compromised due to a loss of Sod1 activity, consistent with the model that yeast imports copper to ensure Sod1 activity and Rad53 signaling. Crucially, the Mac1 transcription factor undergoes changes in its redox state in response to changing levels of copper or MMS. This study has therefore identified a novel regulatory relationship between cellular redox, copper homeostasis, and the DNA damage response in yeast. PMID:23959798

Body of Knowledge (BOK) for Copper Wire Bonds

NASA Technical Reports Server (NTRS)

Rutkowski, E.; Sampson, M. J.

2015-01-01

Copper wire bonds have replaced gold wire bonds in the majority of commercial semiconductor devices for the latest technology nodes. Although economics has been the driving mechanism to lower semiconductor packaging costs for a savings of about 20% by replacing gold wire bonds with copper, copper also has materials property advantages over gold. When compared to gold, copper has approximately: 25% lower electrical resistivity, 30% higher thermal conductivity, 75% higher tensile strength and 45% higher modulus of elasticity. Copper wire bonds on aluminum bond pads are also more mechanically robust over time and elevated temperature due to the slower intermetallic formation rate - approximately 1/100th that of the gold to aluminum intermetallic formation rate. However, there are significant tradeoffs with copper wire bonding - copper has twice the hardness of gold which results in a narrower bonding manufacturing process window and requires that the semiconductor companies design more mechanically rigid bonding pads to prevent cratering to both the bond pad and underlying chip structure. Furthermore, copper is significantly more prone to corrosion issues. The semiconductor packaging industry has responded to this corrosion concern by creating a palladium coated copper bonding wire, which is more corrosion resistant than pure copper bonding wire. Also, the selection of the device molding compound is critical because use of environmentally friendly green compounds can result in internal CTE (Coefficient of Thermal Expansion) mismatches with the copper wire bonds that can eventually lead to device failures during thermal cycling. Despite the difficult problems associated with the changeover to copper bonding wire, there are billions of copper wire bonded devices delivered annually to customers. It is noteworthy that Texas Instruments announced in October of 2014 that they are shipping microcircuits containing copper wire bonds for safety critical automotive applications. An evaluation of copper wire bond technology for applicability to spaceflight hardware may be warranted along with concurrently compiling a comprehensive understanding of the failure mechanisms involved with copper wire bonded semiconductor devices.

Ring World

NASA Image and Video Library

2007-03-01

Our robotic emissary, flying high above Saturn, captured this view of an alien copper-colored ring world. The overexposed planet has deliberately been removed to show the unlit rings alone, seen from an elevation of 60 degrees

Mining-related metals in terrestrial food webs of the upper Clark Fork River basin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pastorok, R.A.; LaTier, A.J.; Butcher, M.K.

1994-12-31

Fluvial deposits of tailings and other mining-related waste in selected riparian habitats of the Upper Clark Fork River basin (Montana) have resulted in metals enriched soils. The significance of metals exposure to selected wildlife species was evaluated by measuring tissue residues of metals (arsenic, cadmium, copper, lead, zinc) in key dietary species, including dominant grasses (tufted hair grass and redtop), willows, alfalfa, barley, invertebrates (grasshoppers, spiders, and beetles), and deer mice. Average metals concentrations in grasses, invertebrates, and deer mice collected from tailings-affected sites were elevated relative to reference to reference levels. Soil-tissue bioconcentration factors for grasses and invertebrates weremore » generally lower than expected based on the range of values in the literature, indicating the reduced bioavailability of metals from mining waste. In general, metals concentrations in willows, alfalfa, and barley were not elevated above reference levels. Using these data and plausible assumptions for other exposure parameters for white-tailed deer, red fox, and American kestrel, metals intake was estimated for soil and diet ingestion pathways. Comparisons of exposure estimates with toxicity reference values indicated that the elevated concentrations of metals in key food web species do not pose a significant risk to wildlife.« less

High-Iron Consumption Impairs Growth and Causes Copper-Deficiency Anemia in Weanling Sprague-Dawley Rats

PubMed Central

Ha, Jung-Heun; Doguer, Caglar; Wang, Xiaoyu; Flores, Shireen R.; Collins, James F.

2016-01-01

Iron-copper interactions were described decades ago; however, molecular mechanisms linking the two essential minerals remain largely undefined. Investigations in humans and other mammals noted that copper levels increase in the intestinal mucosa, liver and blood during iron deficiency, tissues all important for iron homeostasis. The current study was undertaken to test the hypothesis that dietary copper influences iron homeostasis during iron deficiency and iron overload. We thus fed weanling, male Sprague-Dawley rats (n = 6-11/group) AIN-93G-based diets containing high (~8800 ppm), adequate (~80) or low (~11) iron in combination with high (~183), adequate (~8) or low (~0.9) copper for 5 weeks. Subsequently, the iron- and copper-related phenotype of the rats was assessed. Rats fed the low-iron diets grew slower than controls, with changes in dietary copper not further influencing growth. Unexpectedly, however, high-iron (HFe) feeding also impaired growth. Furthermore, consumption of the HFe diet caused cardiac hypertrophy, anemia, low serum and tissue copper levels and decreased circulating ceruloplasmin activity. Intriguingly, these physiologic perturbations were prevented by adding extra copper to the HFe diet. Furthermore, higher copper levels in the HFe diet increased serum nonheme iron concentration and transferrin saturation, exacerbated hepatic nonheme iron loading and attenuated splenic nonheme iron accumulation. Moreover, serum erythropoietin levels, and splenic erythroferrone and hepatic hepcidin mRNA levels were altered by the dietary treatments in unanticipated ways, providing insight into how iron and copper influence expression of these hormones. We conclude that high-iron feeding of weanling rats causes systemic copper deficiency, and further, that copper influences the iron-overload phenotype. PMID:27537180

A cytosolic copper storage protein provides a second level of copper tolerance in Streptomyces lividans.

PubMed

Straw, Megan L; Chaplin, Amanda K; Hough, Michael A; Paps, Jordi; Bavro, Vassiliy N; Wilson, Michael T; Vijgenboom, Erik; Worrall, Jonathan A R

2018-01-24

Streptomyces lividans has a distinct dependence on the bioavailability of copper for its morphological development. A cytosolic copper resistance system is operative in S. lividans that serves to preclude deleterious copper levels. This system comprises of several CopZ-like copper chaperones and P 1 -type ATPases, predominantly under the transcriptional control of a metalloregulator from the copper sensitive operon repressor (CsoR) family. In the present study, we discover a new layer of cytosolic copper resistance in S. lividans that involves a protein belonging to the newly discovered family of copper storage proteins, which we have named Ccsp (cytosolic copper storage protein). From an evolutionary perspective, we find Ccsp homologues to be widespread in Bacteria and extend through into Archaea and Eukaryota. Under copper stress Ccsp is upregulated and consists of a homotetramer assembly capable of binding up to 80 cuprous ions (20 per protomer). X-ray crystallography reveals 18 cysteines, 3 histidines and 1 aspartate are involved in cuprous ion coordination. Loading of cuprous ions to Ccsp is a cooperative process with a Hill coefficient of 1.9 and a CopZ-like copper chaperone can transfer copper to Ccsp. A Δccsp mutant strain indicates that Ccsp is not required under initial copper stress in S. lividans, but as the CsoR/CopZ/ATPase efflux system becomes saturated, Ccsp facilitates a second level of copper tolerance.

Nano Copper Induces Apoptosis in PK-15 Cells via a Mitochondria-Mediated Pathway.

PubMed

Zhang, Hui; Chang, Zhenyu; Mehmood, Khalid; Abbas, Rao Zahid; Nabi, Fazul; Rehman, Mujeeb Ur; Wu, Xiaoxing; Tian, Xinxin; Yuan, Xiaodan; Li, Zhaoyang; Zhou, Donghai

2018-01-01

Nano-sized copper particles are widely used in various chemical, physical, and biological fields. However, earlier studies have shown that nano copper particles (40-100 μg/mL) can induce cell toxicity and apoptosis. Therefore, this study was conducted to investigate the role of nano copper in mitochondrion-mediated apoptosis in PK-15 cells. The cells were treated with different doses of nano copper (20, 40, 60, and 80 μg/mL) to determine the effects of apoptosis using acridine orange/ethidium bromide (AO/EB) fluorescence staining and a flow cytometry assay. The levels of malondialdehyde (MDA) and superoxide dismutase (SOD) in the PK-15 cells were examined using commercially available kits. Moreover, the mRNA levels of the Bax, Bid, Caspase-3, and CYCS genes were assessed by real-time PCR. The results revealed that nano copper exposure induced apoptosis and changed the mitochondrial membrane potential. In addition, nano copper significantly altered the levels of the Bax, Bid, Caspase-3, and CYCS genes at a concentration of 40 μg/mL. To summarize, nano copper significantly (P < 0.05) decreased the level of SOD and increased the level of MDA in PK-15 cells. Altogether, these results suggest that nano copper can play an important role in inducing the apoptotic pathway in PK-15 cells, which may be the mechanism by which nano copper induces nephrotoxicity.

Hepatocellular Carcinoma: An Unusual Complication of Longstanding Wilson Disease.

PubMed

Gunjan, Deepak; Shalimar; Nadda, Neeti; Kedia, Saurabh; Nayak, Baibaswata; Paul, Shashi B; Gamanagatti, Shivanand Ramachandra; Acharya, Subrat K

2017-06-01

Wilson disease is caused by the accumulation of copper in the liver, brain or other organs, due to the mutation in ATP7B gene, which encodes protein that helps in excretion of copper in the bile canaliculus. Clinical presentation varies from asymptomatic elevation of transaminases to cirrhosis with decompensation. Hepatocellular carcinoma is a known complication of cirrhosis, but a rare occurrence in Wilson disease. We present a case of neurological Wilson disease, who later developed decompensated cirrhosis and hepatocellular carcinoma.

Ligand- and base-free copper(II)-catalyzed C-N bond formation: cross-coupling reactions of organoboron compounds with aliphatic amines and anilines.

PubMed

Quach, Tan D; Batey, Robert A

2003-11-13

[reaction: see text] A ligandless and base-free Cu-catalyzed protocol for the cross-coupling of arylboronic acids and potassium aryltrifluoroborate salts with primary and secondary aliphatic amines and anilines is described. The process utilizes catalytic copper(II) acetate monohydrate and 4 A molecular sieves in dichloromethane at slightly elevated temperatures under an atmosphere of oxygen. A broad range of functional groups are tolerated on both of the cross-coupling partners.

Heterogeneity of Systemic Oxidative Stress Profiles in COPD: A Potential Role of Gender.

PubMed

Maury, Jonathan; Gouzi, Farés; De Rigal, Philippe; Heraud, Nelly; Pincemail, Joël; Molinari, Nicolas; Pomiès, Pascal; Laoudj-Chenivesse, Dalila; Mercier, Jacques; Préfaut, Christian; Hayot, Maurice

2015-01-01

Oxidative stress (OS) plays a key role in the muscle impairment and exercise capacity of COPD patients. However, the literature reveals that systemic OS markers show great heterogeneity, which may hinder the prescription of effective antioxidant supplementation. This study therefore aimed to identify OS markers imbalance of COPD patients, relative to validated normal reference values, and to investigate the possibility of systemic OS profiles. We measured systemic enzymatic/nonenzymatic antioxidant and lipid peroxidation (LP) levels in 54 stable COPD patients referred for a rehabilitation program. The main systemic antioxidant deficits in these patients concerned vitamins and trace elements. Fully 89% of the COPD patients showed a systemic antioxidant imbalance which may have caused the elevated systemic LP levels in 69% of them. Interestingly, two patient profiles (clusters 3 and 4) had a more elevated increase in LP combined with increased copper and/or decreased vitamin C, GSH, and GPx. Further analysis revealed that the systemic LP level was higher in COPD women and associated with exercise capacity. Our present data therefore support future supplementations with antioxidant vitamins and trace elements to improve exercise capacity, but COPD patients will probably show different positive responses.

Residues of environmental pollutants and necropsy data for eastern United States ospreys, 1964-1973

USGS Publications Warehouse

Wiemeyer, Stanley N.; Lamont, T.G.; Locke, L.N.

1980-01-01

Thirty-three ospreys (Pandion haliaetus) that were found dead or moribund in the Eastern United States between 1964 and 1973 were necropsied. The brains and carcasses of 26 of these birds were analyzed for organochlorines. The livers of 18 and the kidneys of 7 were analyzed for selected metals. Most adults were recovered in April and May and most immatures were recovered in August through October. The adult sex ratio was highly unbalanced in favor of females. Major causes of mortality were impact injuries, emaciation, shooting, and respiratory infections. Of special interest were two birds with malignant tumors and one with steatitis. Many birds had undergone marked weight losses resulting in mobilization and redistribution of organochlorine residues. Organochlorines were detected in the birds at the following percentages: DDE l00%, PCB 96%, DDD 92%, dieldrin 88%, chlordanes (including nonachlors) 82%, DDT 65%, and heptachlor epoxide 38%. Organochlorine levels tended to be higher in adults than in immatures. One adult from South Carolina had a potentially dangerous level of dieldrin in its brain, which might have contributed to its death. Immature ospreys from Maryland had extremely elevated levels of copper in their livers compared with immatures from other areas and all adults. One immature from Maryland had an elevated level of arsenic in its liver, which might have contributed to its death. One adult from Florida that had died of impact injuries had potentially dangerous levels of mercury in both liver and kidney and slightly elevated levels of cadmium in these tissues. Additional birds appeared to have been exposed to contamination of the environment by arsenic and mercury. The levels of chromium, zinc, and lead in livers appeared normal.

Zinc and copper status of women by physical activity and menstrual status

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, A.; Deuster, P.A.; Kyle, S.B.

The zinc and copper status of 33 eumenorrheic (EU) and 12 amenorrheic (AM) female marathon runners and 19 EU and 8 AM nonrunners were determined from 3-day diet records and plasma and erythrocyte (RBC) levels. The study was conducted as a completely randomized 2 x 2 factorial. Mean daily zinc intakes of all groups fell below the recommended dietary allowances. Copper intakes of runners (EU = 1.3 mg; AM = 1.3 mg) were not significantly different. Menstrual status did not affect plasma zinc, RBC zinc or plasma copper levels. Physical activity however, affected RBC zinc and plasma copper levels. Bothmore » these parameters were significantly higher in runners. These findings suggest that exercise influences blood zinc and copper levels.« less

Acclimation to low level exposure of copper in Bufo arenarum embryos: linkage of effects to tissue residues.

PubMed

Herkovits, Jorge; Pérez-Coll, Cristina Silvia

2007-06-01

The acclimation possibilities to copper in Bufo arenarum embryos was evaluated by means of three different low level copper exposure conditions during 14 days. By the end of the acclimation period the copper content in control embryos was 1.04 +/- 0.09 microg g(-1) (wet weight) while in all the acclimated embryos a reduction of about 25% of copper was found. Thus copper content could be considered as a biomarker of low level exposure conditions. Batches of 10 embryos (by triplicate) from each acclimation condition were challenged with three different toxic concentrations of copper. As a general pattern, the acclimation protocol to copper exerted a transient beneficial effect on the survival of the Bufo arenarum embryos. The acclimation phenomenon could be related to the selection of pollution tolerant organisms within an adaptive process and therefore the persistence of information within an ecological system following a toxicological stressor.

Metallochaperone for Cu,Zn-superoxide dismutase (CCS) protein but not mRNA is higher in organs from copper-deficient mice and rats.

PubMed

Prohaska, Joseph R; Broderius, Margaret; Brokate, Bruce

2003-09-15

Cu,Zn-superoxide dismutase (SOD1) is an abundant metalloenzyme important in scavenging superoxide ions. Cu-deficient rats and mice have lower SOD1 activity and protein, possibly because apo-SOD1 is degraded faster than holo-SOD1. SOD1 interacts with and requires its metallochaperone CCS for donating copper. We produced dietary Cu deficiency in rodents to determine if the reduction in SOD1 was related to the level of its specific metallochaperone CCS. CCS levels determined by immunoblot were 2- to 3-fold higher in liver, heart, kidney, and brain from male Cu-deficient rats and mice under a variety of conditions. CCS was also higher in livers of Cu-deficient dams. Interestingly, CCS levels in brain of Cu-deficient mice were also higher even though SOD1 activity and protein were not altered, suggesting that the rise in CCS is correlated with altered Cu status rather than a direct result of lower SOD1. A DNA probe specific for rat CCS detected a single transcript by Northern blot hybridization with liver RNA. CCS mRNA levels in mouse and rat liver were not altered by dietary treatment. These results suggest a posttranscriptional mechanism for higher CCS protein when Cu is limiting in the cell, perhaps due to slower protein turnover. Elevation in CCS level is one of the most dramatic alterations in Cu binding proteins accompanying Cu deficiency and may be useful to assess Cu status.

Chronic copper poisoning in Angora kids.

PubMed

Belford, C J; Raven, C R; Black, H

1989-12-01

The investigation of five field cases of chronic copper poisoning in a group of 100 Angora kids is reported. Toxicity was confirmed by the demonstration of Heinz body anaemias, necrotizing liver disease, haemoglobinuric nephrosis and excessive levels of copper in blood, livers and kidneys. The dietary history of the kids is described. Tissue levels of copper and reported interactions between selenium, zinc and copper are discussed. Therapeutic and preventative measures are suggested.

A practical comparison of Copper Bromide Laser for the treatment of vascular lesions.

PubMed

Lee, SunWoo; Lee, TaeBum; Kim, HoYoun; Kim, JungSoo; Eun, HyeJun; Kim, RyunKyung

2013-01-01

The recent rapid growth in demand for aesthetic non-invasive laser treatments such as unwanted skin rejuvenation, removal of age-related vascular blemishes has led to a boom in the medical devices to treat these conditions. Among diverse laser for skin treatment, copper bromide laser is a very effective, safe, and well tolerated treatment for facial telangiectasia at various energy levels and the most important thing of the copper bromide laser device is that the stability of the energy. However there is no evidence about effective copper bromide laser's energy level for the treatment of vascular lesions. We compared energy stability and treatment performance between two energy levels in 2 W and 8 W which commonly use in laser treatment for the vascular lesions. 8 W copper bromide laser was more stable compared than 2 W copper bromide laser. Also, 8 W copper bromide laser was effectively superior to 2 W copper bromide laser in treatment of vascular legion. Consequently, 8 W copper bromide laser treatment for vascular lesion might be more suitable than 2 W copper bromide laser.

Ultraviolet Light-Assisted Copper Oxide Nanowires Hydrogen Gas Sensor

NASA Astrophysics Data System (ADS)

Sihar, Nabihah; Tiong, Teck Yaw; Dee, Chang Fu; Ooi, Poh Choon; Hamzah, Azrul Azlan; Mohamed, Mohd Ambri; Majlis, Burhanuddin Yeop

2018-05-01

We fabricated copper oxide nanowires (CuO NWs) ultraviolet (UV) light-assisted hydrogen gas sensor. The fabricated sensor shows promising sensor response behavior towards 100 ppm of H2 at room temperature and elevated temperature at 100 °C when exposed to UV light (3.0 mW/cm2). One hundred-cycle device stability test has been performed, and it is found that for sample elevated at 100 °C, the UV-activated sample achieved stability in the first cycle as compared to the sample without UV irradiation which needed about 10 cycles to achieve stability at the initial stage, whereas the sample tested at room temperature was able to stabilize with the aid of UV irradiation. This indicates that with the aid of UV light, after some "warming up" time, it is possible for the conventional CuO NW sensor which normally work at elevated temperature to function at room temperature because UV source is speculated to play a dominant role to increase the interaction of the surface of CuO NWs and hydrogen gas molecules absorbed after the light exposure.

Dysregulation of iron and copper homeostasis in nonalcoholic fatty liver

PubMed Central

Aigner, Elmar; Weiss, Günter; Datz, Christian

2015-01-01

Elevated iron stores as indicated by hyperferritinemia with normal or mildly elevated transferrin saturation and mostly mild hepatic iron deposition are a characteristic finding in subjects with non-alcoholic fatty liver disease (NAFLD). Excess iron is observed in approximately one third of NAFLD patients and is commonly referred to as the “dysmetabolic iron overload syndrome”. Clinical evidence suggests that elevated body iron stores aggravate the clinical course of NAFLD with regard to liver-related and extrahepatic disease complications which relates to the fact that excess iron catalyses the formation of toxic hydroxyl-radicals subsequently resulting in cellular damage. Iron removal improves insulin sensitivity, delays the onset of type 2 diabetes mellitus, improves pathologic liver function tests and likewise ameliorates NAFLD histology. Several mechanisms contribute to pathologic iron accumulation in NAFLD. These include impaired iron export from hepatocytes and mesenchymal Kupffer cells as a consequence of imbalances in the concentrations of iron regulatory factors, such as hepcidin, cytokines, copper or other dietary factors. This review summarizes the knowledge about iron homeostasis in NAFLD and the rationale for its therapeutic implications. PMID:25729473

Ultraviolet Light-Assisted Copper Oxide Nanowires Hydrogen Gas Sensor.

PubMed

Sihar, Nabihah; Tiong, Teck Yaw; Dee, Chang Fu; Ooi, Poh Choon; Hamzah, Azrul Azlan; Mohamed, Mohd Ambri; Majlis, Burhanuddin Yeop

2018-05-15

We fabricated copper oxide nanowires (CuO NWs) ultraviolet (UV) light-assisted hydrogen gas sensor. The fabricated sensor shows promising sensor response behavior towards 100 ppm of H 2 at room temperature and elevated temperature at 100 °C when exposed to UV light (3.0 mW/cm 2 ). One hundred-cycle device stability test has been performed, and it is found that for sample elevated at 100 °C, the UV-activated sample achieved stability in the first cycle as compared to the sample without UV irradiation which needed about 10 cycles to achieve stability at the initial stage, whereas the sample tested at room temperature was able to stabilize with the aid of UV irradiation. This indicates that with the aid of UV light, after some "warming up" time, it is possible for the conventional CuO NW sensor which normally work at elevated temperature to function at room temperature because UV source is speculated to play a dominant role to increase the interaction of the surface of CuO NWs and hydrogen gas molecules absorbed after the light exposure.

Influence of Alloying upon Grain-Boundary Creep

NASA Technical Reports Server (NTRS)

Rhines, F N; Bond, W E; Kissel, M A

1957-01-01

Grain-boundary displacement, occurring in bicrystals during creep at elevated temperature (350 degrees c), has been measured as a function of the copper content (0.1 to 3 percent) in a series of aluminum-rich aluminum-copper solid-solution alloys. The minimums in stress and temperature, below which grain-boundary motion does not occur, increase regularly with the copper content as would be expected if recovery is necessary for movement. Otherwise, the effects, if any, of the copper solute upon grain-boundary displacement and its rate are too small for identification by the experimental technique employed. It was shown, additionally, that grain-boundary displacement appears regular and proceeds at a constant rate if observed parallel to the stress axis, whereas the motion is seen to occur in a sequence of surges and the rate to diminish with time if the observations are made perpendicular to the stress axis.

Roofing Materials Assessment: Investigation of Five Metals in Runoff from Roofing Materials.

PubMed

Winters, Nancy; Granuke, Kyle; McCall, Melissa

2015-09-01

To assess the contribution of five toxic metals from new roofing materials to stormwater, runoff was collected from 14 types of roofing materials and controls during 20 rain events and analyzed for metals. Many of the new roofing materials evaluated did not show elevated metals concentrations in the runoff. Runoff from several other roofing materials was significantly higher than the controls for arsenic, copper, and zinc. Notably, treated wood shakes released arsenic and copper, copper roofing released copper, PVC roofing released arsenic, and Zincalume® and EPDM roofing released zinc. For the runoff from some of the roofing materials, metals concentrations decreased significantly over an approximately one-year period of aging. Metals concentrations in runoff were demonstrated to depend on a number of factors, such as roofing materials, age of the materials, and climatic conditions. Thus, application of runoff concentrations from roofing materials to estimate basin-wide releases should be undertaken cautiously.

Polymodal Responses in C. elegans Phasmid Neurons Rely on Multiple Intracellular and Intercellular Signaling Pathways

PubMed Central

Zou, Wenjuan; Cheng, Hankui; Li, Shitian; Yue, Xiaomin; Xue, Yadan; Chen, Sixi; Kang, Lijun

2017-01-01

Animals utilize specialized sensory neurons enabling the detection of a wide range of environmental stimuli from the presence of toxic chemicals to that of touch. However, how these neurons discriminate between different kinds of stimuli remains poorly understood. By combining in vivo calcium imaging and molecular genetic manipulation, here we investigate the response patterns and the underlying mechanisms of the C. elegans phasmid neurons PHA/PHB to a variety of sensory stimuli. Our observations demonstrate that PHA/PHB neurons are polymodal sensory neurons which sense harmful chemicals, hyperosmotic solutions and mechanical stimulation. A repulsive concentration of IAA induces calcium elevations in PHA/PHB and both OSM-9 and TAX-4 are essential for IAA-sensing in PHA/PHB. Nevertheless, the PHA/PHB neurons are inhibited by copper and post-synaptically activated by copper removal. Neuropeptide is likely involved in copper removal-induced calcium elevations in PHA/PHB. Furthermore, mechanical stimulation activates PHA/PHB in an OSM-9-dependent manner. Our work demonstrates how PHA/PHB neurons respond to multiple environmental stimuli and lays a foundation for the further understanding of the mechanisms of polymodal signaling, such as nociception, in more complex organisms. PMID:28195191

40 CFR 141.80 - General requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... and copper action levels measured in samples collected at consumers' taps. (c) Lead and copper action levels. (1) The lead action level is exceeded if the concentration of lead in more than 10 percent of tap... action level is exceeded if the concentration of copper in more than 10 percent of tap water samples...

Membrane Lipid Peroxidation in Copper Alloy-Mediated Contact Killing of Escherichia coli

PubMed Central

Hong, Robert; Kang, Tae Y.; Michels, Corinne A.

2012-01-01

Copper alloy surfaces are passive antimicrobial sanitizing agents that kill bacteria, fungi, and some viruses. Studies of the mechanism of contact killing in Escherichia coli implicate the membrane as the target, yet the specific component and underlying biochemistry remain unknown. This study explores the hypothesis that nonenzymatic peroxidation of membrane phospholipids is responsible for copper alloy-mediated surface killing. Lipid peroxidation was monitored with the thiobarbituric acid-reactive substances (TBARS) assay. Survival, TBARS levels, and DNA degradation were followed in cells exposed to copper alloy surfaces containing 60 to 99.90% copper or in medium containing CuSO4. In all cases, TBARS levels increased with copper exposure levels. Cells exposed to the highest copper content alloys, C11000 and C24000, exhibited novel characteristics. TBARS increased immediately at a very rapid rate but peaked at about 30 min. This peak was associated with the period of most rapid killing, loss in membrane integrity, and DNA degradation. DNA degradation is not the primary cause of copper-mediated surface killing. Cells exposed to the 60% copper alloy for 60 min had fully intact genomic DNA but no viable cells. In a fabR mutant strain with increased levels of unsaturated fatty acids, sensitivity to copper alloy surface-mediated killing increased, TBARS levels peaked earlier, and genomic DNA degradation occurred sooner than in the isogenic parental strain. Taken together, these results suggest that copper alloy surface-mediated killing of E. coli is triggered by nonenzymatic oxidative damage of membrane phospholipids that ultimately results in the loss of membrane integrity and cell death. PMID:22247141

Copper supplementation amplifies the anti-tumor effect of curcumin in oral cancer cells.

PubMed

Lee, Hui-Mei; Patel, Vyomesh; Shyur, Lie-Fen; Lee, Wai-Leng

2016-11-15

Oral cancer is the sixth most common cancer worldwide and 90% of oral malignancies are caused by oral squamous cell carcinoma (OSCC). Curcumin, a phytocompound derived from turmeric (Curcuma longa) was observed to have anti-cancer activity which can be developed as an alternative treatment option for OSCC. However, OSCC cells with various clinical-pathological features respond differentially to curcumin treatment. Intracellular copper levels have been reported to correlate with tumor pathogenesis and affect the sensitivity of cancer cells to cytotoxic chemotherapy. We hypothesized that intracellular copper levels may affect the sensitivity of oral cancer cells to curcumin. We analysed the correlation between intracellular copper levels and response to curcumin treatment in a panel of OSCC cell lines derived from oral cancer patients. Exogenous copper was supplemented in curcumin insensitive cell lines to observe the effect of copper on curcumin-mediated inhibition of cell viability and migration, as well as induction of oxidative stress and apoptosis. Protein markers of cell migration and oxidative stress were also analysed using Western blotting. Concentrations of curcumin which inhibited 50% OSCC cell viability (IC 50 ) was reduced up to 5 times in the presence of 250 µM copper. Increased copper level in curcumin-treated OSCC cells was accompanied by the induction of intracellular ROS and increased level of Nrf2 which regulates oxidative stress responses in cells. Supplemental copper also inhibited migration of curcumin-treated cells with enhanced level of E-cadherin and decreased vimentin, indications of suppressed epithelial-mesenchymal transition. Early apoptosis was observed in combined treatment but not in treatment with curcumin or copper alone. Supplement of copper significantly enhanced the inhibitory effect of curcumin treatment on migration and viability of oral cancer cells. Together, these findings provide molecular insight into the role of copper in overcoming insensitivity of oral cancer cells to curcumin treatment, suggesting a new strategy for cancer therapy. Copyright © 2016 Elsevier GmbH. All rights reserved.

[Changes in serum lipids in rats treated with oral cooper].

PubMed

Alarcón-Corredor, O M; Carnevalí de Tatá, E; Reinosa-Füller, J; Contreras, Y; Ramírez de Fernández, M; Yánez-Domínguez, C

2000-09-01

Disturbances in lipid metabolism during copper deficiency in rats are well recognized. Copper deficiency is associated with the spontaneous retention of hepatic iron. Previous studies have reported that hypercholesterolemia and hypertriglyceridemia are associated with elevated hepatic iron concentrations in copper deficient rats. There was a direct relationship between the magnitude of blood lipids and the concentration of hepatic iron. Based on these data, it has been hypothesized that iron was responsible for the development of lipemia of copper deficiency. In this study was determined the effect of increasing doses of Cu(10, 20 and 50 ppm) in the diet, on the serum total lipids, total cholesterol, triglycerides (triacylglicerols), phospholipids, non-esterified fatty acids (NEFA) and liver iron and zinc concentrations in normal rats. The results were compared with normal rats that received a balanced diet containing 0.6 and 6 ppm of Cu, respectively. The results show that Cu-supplement diminished the cholesterol and triglyceride serum levels, increased the level of phospholipids, NEFA and concomitantly decreased the hepatic concentrations of Fe and Zn. There was a statistically significant (p < 0.05) simple correlation between triglycerides and liver Fe (r = 0.917; R2 = 64.03%), cholesterol and liver Zn (r = 0.872; R2 = 76.07%), cholesterol and liver Fe (r = 0.995; R2 = 99.10%), liver Fe and liver Cu (r = -0.612), liver Fe and liver Zn (r = 0.837), liver Cu and liver Zn (r = -0.612), and serum triglycerides and liver Zn (r = 0.967). The mechanism(s) by which Fe and Zn determine these changes is not known; none of the enzymes that act in cholesterol and triglyceride metabolism and biosynthesis require Fe and/or Zn. The increase of NEFA is due to changes in the process of lipolysis and re-esterification of the fatty acids in blood. However, additional studies are needed for the precise mechanisms of this interrelationships to be clarified.

Rupture testing for the quality control of electrodeposited copper interconnections in high-speed, high-density circuits

NASA Technical Reports Server (NTRS)

Zakraysek, Louis

1987-01-01

Printed Wiring Multilayer Board (PWMLB) structures for high speed, high density circuits are prone to failure due to the microcracking of electrolytic copper interconnections. The failure can occur in the foil that makes up the inner layer traces or in the plated through holes (PTH) deposit that forms the layer to layer interconnections. It is shown that there are some distinctive differences in the quality of Type E copper and that these differences can be detected before its use in a PWMLB. It is suggested that the strength of some Type E copper can be very low when the material is hot and that it is the use of this poor quality material in a PWMLB that results in PTH and inner layer microcracking. Since the PWMLB failure in question are induced by a thermal stress, and since the poorer grades of Type E materials used in these structures are susceptible to premature failure under thermal stress, the use of elevated temperature rupture and creep rupture testing is proposed as a means for screening copper foil, or its PTH equivalent, in order to eliminate the problem of Type E copper microcracking in advanced PWMLBs.

In vivo toxic effects of 4-methoxy-5-hydroxy-canthin-6-one in zebrafish embryos via copper dyshomeostasis and oxidative stress.

PubMed

Gong, Guiyi; Jiang, Lingling; Lin, Qinghua; Liu, Wenyuan; He, Ming-Fang; Zhang, Jie; Feng, Feng; Qu, Wei; Xie, Ning

2018-01-01

Dysfunction of copper homeostasis can lead to a host of disorders, which might be toxic sometimes. 4-Methoxy-5-hydroxy-canthin-6-one (CAN) is one of the major constituents from Picrasma quassioides and responsible for its therapeutic effects. In this work, we evaluated the toxic effect of CAN (7.5μM) on zebrafish embryos. CAN treatment decreased survival, delayed hatching time and induced malformations (loss of pigmentation, pericardial edema, as well as hematologic and neurologic abnormalities). Besides, exogenous copper supplementation rescued the pigmentation and cardiovascular defects in CAN-treated embryos. Further spectroscopic studies revealed a copper-chelating activity of CAN. Then its regulation on the expressions of copper homeostasis related genes also be analyzed. In addition, CAN lowered the total activity of SOD, elevated the ROS production and altered the oxidative related genes transcriptions, which led to oxidative stress. In conclusion, we demonstrated that CAN (7.5μM) might exert its toxic effects in zebrafish embryos by causing copper dyshomeostasis and oxidative stress. It will give insight into the risk assessment and prevention of CAN-mediated toxicity. Copyright © 2017 Elsevier Inc. All rights reserved.

Pharmacological Evaluation of Naproxen Metal Complexes on Antinociceptive, Anxiolytic, CNS Depressant, and Hypoglycemic Properties

PubMed Central

Das, Narhari; Abdur Rahman, S. M.

2016-01-01

Purpose. The present study was designed to investigate the antinociceptive, anxiolytic, CNS depressant, and hypoglycemic effects of the naproxen metal complexes. Methods. The antinociceptive activity was evaluated by acetic acid-induced writhing method and radiant heat tail-flick method while anxiolytic activity was evaluated by elevated plus maze model. The CNS depressant activity of naproxen metal complexes was assessed using phenobarbitone-induced sleeping time test and the hypoglycemic test was performed using oral glucose tolerance test. Results. Metal complexes significantly (P < 0.001) reduced the number of abdominal muscle contractions induced by 0.7% acetic acid solution in a dose dependent manner. At the dose of 25 mg/kg body weight p.o. copper, cobalt, and zinc complexes exhibited higher antinociceptive activity having 59.15%, 60.56%, and 57.75% of writhing inhibition, respectively, than the parent ligand naproxen (54.93%). In tail-flick test, at both doses of 25 and 50 mg/kg, the copper, cobalt, silver, and zinc complexes showed higher antinociceptive activity after 90 minutes than the parent drug naproxen. In elevated plus maze (EPM) model the cobalt and zinc complexes of naproxen showed significant anxiolytic effects in dose dependent manner, while the copper, cobalt, and zinc complexes showed significant CNS depressant and hypoglycemic activity. Conclusion. The present study demonstrated that copper, cobalt, and zinc complexes possess higher antinociceptive, anxiolytic, CNS depressant, and hypoglycemic properties than the parent ligand. PMID:27478435

SOLVING COPPER CORROSION PROBLEMS WHILE MAINTAINING LEAD CONTROL IN A HIGH ALKALINITY WATER USING ORTHOPHOSPHATE

EPA Science Inventory

Lead and Copper Rule sampling in 1992 uncovered high copper levels in many homes in the Indian Hill Water Works, Ohio (IHWW) water system. The 90th percentile copper and lead levels were 1.63 mg/L and 0.012 mg/L, respectively. IHWW supplies water to several suburban communities t...

Formation of copper precipitates in silicon

NASA Astrophysics Data System (ADS)

Flink, Christoph; Feick, Henning; McHugo, Scott A.; Mohammed, Amna; Seifert, Winfried; Hieslmair, Henry; Heiser, Thomas; Istratov, Andrei A.; Weber, Eicke R.

1999-12-01

The formation of copper precipitates in silicon was studied after high-temperature intentional contamination of p- and n-type FZ and Cz-grown silicon and quench to room temperature. With the Transient Ion Drift (TID) technique on p-type silicon a critical Fermi level position at EC-0.2 eV was found. Only if the Fermi level position, which is determined by the concentrations of the acceptors and the copper donors, surpasses this critical value precipitation takes place. If the Fermi level is below this level the supersaturated interstitial copper diffuses out. An electrostatic precipitation model is introduced that correlates the observed precipitation behavior with the electrical activity of the copper precipitates as detected with Deep Level Transient Spectroscopy (DLTS) on n-type and with Minority Carrier Transient Spectroscopy (MCTS) on p-type silicon.

Cancer risk in relation to serum copper levels.

PubMed

Coates, R J; Weiss, N S; Daling, J R; Rettmer, R L; Warnick, G R

1989-08-01

A nested, matched case-control study was conducted to assess the relationship between serum levels of copper and the subsequent risk of cancer. One hundred thirty-three cases of cancer were identified during 1974-1984 among 5000 members of a northwest Washington State employee cohort from whom serum specimens had been previously obtained and stored. Two hundred forty-one controls were selected at random from the cohort and were matched to the cases on the basis of age, sex, race, and date of blood draw. Serum copper levels were measured by atomic absorption spectrometry. Risk of a subsequent diagnosis of cancer was positively associated with serum copper levels, but only among those cases diagnosed within 4 years of the time the serum specimens were collected. Among cases diagnosed more than 4 years after specimen collection, there was no consistent association between serum copper levels and risk. Adjustment for age, sex, race, occupational status, cigarette smoking, family history of cancer, alcohol consumption, and, among females, use of exogenous hormones had no appreciable effect on these relationships. The findings suggest that the presence of cancer may increase serum copper levels several years prior to its diagnosis. They are less supportive of the hypothesis that serum copper levels affect cancer risk.

Water-quality assessment of the upper Illinois River Basin in Illinois, Indiana, and Wisconsin; major and trace elements in water, sediment, and biota, 1978-90

USGS Publications Warehouse

Fitzpatrick, F.A.; Scudder, B.C.; Crawford, J.K.; Schmidt, A.R.; Sieverling, J.B.

1995-01-01

The distribution of 22 major and trace elements was examined in water, sediment, and biota in the upper Illinois River Basin in Illinois, Indiana, and Wisconsin as part of a pilot National Water-Quality Assessment project done by the U.S. Geological Survey from 1987 through 1990. The 22 elements are aluminum, antimony, arsenic, barium, beryllium, boron, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, molybdenum, nickel, phosphorus, selenium, silver, strontium, vanadium, and zinc. Concentrations of U.S. Environmental Protection Agency (USEPA) priority pollutants among the 22 elements were elevated in the Chicago area in all three aquatic components (water, sediment, and biota). Further, some of the priority pollutants also were found at elevated concentrations in biota in agricultural areas in the basin. Cadmium, chromium, copper, iron, lead, mercury, silver, and zinc concentrations in water exceeded USEPA acute or chronic water-quality criteria at several sites in the Chicago area. Correlations among concentra- tions of elements in water, sediment, and biota were found, but the correlation analysis was hindered by the large proportion of observations less than the minimum reporting level in water. Those sites where water-quality criteria were sometimes exceeded were not always the same sites where concentrations in biota were the largest. This relation indicates that accumulation of these pollutants in biota is confounded by complex geochemical and biological processes that differ throughout the upper Illinois River Basin.

Multimodal LA-ICP-MS and nanoSIMS imaging enables copper mapping within photoreceptor megamitochondria in a zebrafish model of Menkes disease.

PubMed

Ackerman, Cheri M; Weber, Peter K; Xiao, Tong; Thai, Bao; Kuo, Tiffani J; Zhang, Emily; Pett-Ridge, Jennifer; Chang, Christopher J

2018-03-01

Copper is essential for eukaryotic life, and animals must acquire this nutrient through the diet and distribute it to cells and organelles for proper function of biological targets. Indeed, mutations in the central copper exporter ATP7A contribute to a spectrum of diseases, including Menkes disease, with symptoms ranging from neurodegeneration to lax connective tissue. As such, a better understanding of the fundamental impacts of ATP7A mutations on in vivo copper distributions is of relevance to those affected by these diseases. Here we combine metal imaging and optical imaging techniques at a variety of spatial resolutions to identify tissues and structures with altered copper levels in the Calamity gw71 zebrafish model of Menkes disease. Rapid profiling of tissue slices with LA-ICP-MS identified reduced copper levels in the brain, neuroretina, and liver of Menkes fish compared to control specimens. High resolution nanoSIMS imaging of the neuroretina, combined with electron and confocal microscopies, identified the megamitochondria of photoreceptors as loci of copper accumulation in wildtype fish, with lower levels of megamitochondrial copper observed in Calamity gw71 zebrafish. Interestingly, this localized copper decrease does not result in impaired photoreceptor development or altered megamitochondrial morphology, suggesting the prioritization of copper at sufficient levels for maintaining essential mitochondrial functions. Together, these data establish the Calamity gw71 zebrafish as an optically transparent in vivo model for the study of neural copper misregulation, illuminate a role for the ATP7A copper exporter in trafficking copper to the neuroretina, and highlight the utility of combining multiple imaging techniques for studying metals in whole organism settings with spatial resolution.

Effect of dietary copper addition on lipid metabolism in rabbits

PubMed Central

Lei, Liu; Xiaoyi, Sui; Fuchang, Li

2017-01-01

ABSTRACT The present study was conducted to investigate the effect of copper supplementation on lipid metabolism in rabbits. Our study showed dietary copper addition (5-45 mg/kg) increased body mass gain, but decreased fat and liver weights compared with those in the control group (P < 0.05). Copper (45 mg/kg) addition significantly increased the skeletal muscle weight, but inhibited cytoplasmic lipid accumulation in liver, skeletal muscle and adipose tissue (P < 0.05). Compared with the control group, dietary copper addition (45 mg/kg) significantly increased plasma triglyceride levels but decreased very low density lipoprotein levels (P < 0.05). Copper treatment significantly increased gene expression of carnitine palmitoyltransferase (CPT) 1, CPT2 and peroxisome proliferator-activated receptor (PPAR) a in liver (P < 0.05). In skeletal muscle, CPT1, CPT2, fatty acid transport protein, fatty acid-binding protein, and PPARa mRNA as well as phosphorylated AMP-activated protein kinase (AMPK) levels were significantly up-regulated by copper treatment (P < 0.05). Rabbits receiving copper supplementation had higher CPT1, CPT2, PPARa and hormone-sensitive lipase mRNA levels in adipose tissue (P < 0.05). In conclusion, copper promoted skeletal muscle growth and reduced fat accretion. PPARa signaling in liver, skeletal muscle and adipose tissues and AMPK signaling in skeletal muscle tissue were involved in the regulation of lipid metabolism by copper. PMID:28747869

Copper-resistant bacteria reduces oxidative stress and uptake of copper in lentil plants: potential for bacterial bioremediation.

PubMed

Islam, Faisal; Yasmeen, Tahira; Ali, Qasim; Mubin, Muhammad; Ali, Shafaqat; Arif, Muhammad Saleem; Hussain, Sabir; Riaz, Muhammad; Abbas, Farhat

2016-01-01

For effective microbe-assisted bioremediation, metal-resistant plant growth-promoting bacteria (PGPB) must facilitate plant growth by restricting excess metal uptake in plants, leading to prevent its bio-amplification in the ecosystem. The aims of our study were to isolate and characterize copper (Cu)-resistant PGPB from waste water receiving contaminated soil. In addition, we investigated the phytotoxic effect of copper on the lentil plants inoculated with copper-resistant bacteria Providencia vermicola, grown in copper-contaminated soil. Copper-resistant P. vermicola showed multiple plant growth promoting characteristics, when used as a seed inoculant. It protected the lentil plants from copper toxicity with a considerable increase in root and shoot length, plant dry weight and leaf area. A notable increase in different gas exchange characteristics such as A, E, C i , g s , and A/E, as well as increase in N and P accumulation were also recorded in inoculated plants as compared to un-inoculated copper stressed plants. In addition, leaf chlorophyll content, root nodulation, number of pods, 1,000 seed weight were also higher in inoculated plants as compared with non-inoculated ones. Anti-oxidative defense mechanism improved significantly via elevated expression of reactive oxygen species -scavenging enzymes including ascorbate peroxidase, superoxide dismutase, catalase, and guaiacol peroxidase with alternate decrease in malondialdehyde and H2O2 contents, reduced electrolyte leakage, proline, and total phenolic contents suggesting that inoculation of P. vermicola triggered heavy metals stress-related defense pathways under copper stress. Overall, the results demonstrated that the P. vermicola seed inoculation confer heavy metal stress tolerance in lentil plant which can be used as a potent biotechnological tool to cope with the problems of copper pollution in crop plants for better yield.

Ecophysiological and metabolic responses to interactive exposure to nutrients and copper excess in the brown macroalga Cystoseira tamariscifolia.

PubMed

Celis-Plá, Paula S M; Brown, Murray T; Santillán-Sarmiento, Alex; Korbee, Nathalie; Sáez, Claudio A; Figueroa, Félix L

2018-03-01

Global scenarios evidence that contamination due to anthropogenic activities occur at different spatial-temporal scales, being important stressors: eutrophication, due to increased nutrient inputs; and metal pollution, mostly derived from industrial activities. In this study, we investigated ecophysiological and metabolic responses to copper and nutrient excess in the brown macroalga Cystoseira tamariscifolia. Whole plants were incubated in an indoor system under control conditions, two levels of nominal copper (0.5 and 2.0μM), and two levels of nutrient supply for two weeks. Maximal quantum yield (F v /F m ) and maximal electron transport rate (ETR max ) increased under copper exposure. Photosynthetic pigments and phenolic compounds (PC) increased under the highest copper levels. The intra-cellular copper content increased under high copper exposure in both nutrient conditions. C. tamariscifolia from the Atlantic displayed efficient metal exclusion mechanisms, since most of the total copper accumulated by the cell was bound to the cell wall. Copyright © 2018 Elsevier Ltd. All rights reserved.

Acclimation to Low Level Exposure of Copper in Bufo arenarum Embryos: Linkage of Effects to Tissue Residues

PubMed Central

Herkovits, Jorge; Pérez-Coll, Cristina Silvia

2007-01-01

The acclimation possibilities to copper in Bufo arenarum embryos was evaluated by means of three different low level copper exposure conditions during 14 days. By the end of the acclimation period the copper content in control embryos was 1.04 ± 0.09 μg.g−1 (wet weight) while in all the acclimated embryos a reduction of about 25% of copper was found. Thus copper content could be considered as a biomarker of low level exposure conditions. Batches of 10 embryos (by triplicate) from each acclimation condition were challenged with three different toxic concentrations of copper. As a general pattern, the acclimation protocol to copper exerted a transient beneficial effect on the survival of the Bufo arenarum embryos. The acclimation phenomenon could be related to the selection of pollution tolerant organisms within an adaptive process and therefore the persistence of information within an ecological system following a toxicological stressor. PMID:17617681

Evaluation of Thermal Stability of Ausferrite in Austempered Ductile Iron Using Differential Scanning Calorimetry

NASA Astrophysics Data System (ADS)

Warsinski, Karl C.

Austempered Ductile Iron (ADI) is prone to changes in microstructure and mechanical properties when exposed to elevated service temperatures. Differential Scanning Calorimetry has been used to evaluate the stabilizing effects of copper, nickel, molybdenum, and cobalt on the ausferrite structure. Previous studies have conflated the effects of various alloy additions, and little effort has been made to systematically catalog the effects of individual elements. The focus of the current research has been to identify alloying elements that more strongly stabilize the ausferrite structure in order to improve service life of ADI at elevated temperatures. Nickel has been shown to have a moderate stabilizing effect, while copper and molybdenum cause a much sharper increase in activation energy. Cobalt has a high stabilizing effect at 0.5% addition by weight, but a further increase to 2.36% results in a slight decrease in activation energy.

Aluminum-Silicon Alloy Having Improved Properties at Elevated Temperatures and Articles Cast Therefrom

NASA Technical Reports Server (NTRS)

Lee, Jonathan A. (Inventor); Chen, Po-Shou (Inventor)

2002-01-01

An aluminum alloy suitable for high temperature applications, such as heavy duty pistons and other internal combustion applications. having the following composition, by weight percent (wt %): Silicon: 11.0-14.0; Copper: 5.6-8.0; Iron: 0-0.8; Magnesium: 0.5-1.5; Nickel: 0.05-0.9; Manganese: 0.5-1.5; Titanium: 0.05-1.2; Zirconium: 0.12-1.2; Vanadium: 0.05-1.2; Zinc: 0.005-0.9; Strontium: 0.001-0.1; Aluminum: balance. In this alloy the ratio of silicon:magnesium is 10-25, and the ratio of copper:magnesium is 4-15. After an article is cast from this alloy, the article is treated in a solutionizing step which dissolves unwanted precipitates and reduces any segregation present in the original alloy. After this solutionizing step, the article is quenched, and is then aged at an elevated temperature for maximum strength.

Electrochemical fabrication of nanoporous copper films in choline chloride-urea deep eutectic solvent.

PubMed

Zhang, Q B; Abbott, Andrew P; Yang, C

2015-06-14

Nanoporous copper films were fabricated by a facile electrochemical alloying/dealloying process without the need of a template. A deep eutectic solvent made from choline chloride (ChCl) and urea was used with zinc oxide as the metal salt. Cyclic voltammetry was used to characterise the electrochemical reduction of zinc and follow Cu-Zn alloy formation on the copper substrate at elevated temperatures from 353 to 393 K. The alloy formation was confirmed by X-ray diffraction spectra. 3D, open and bicontinuous nanoporous copper films were obtained by in situ electrochemically etching (dealloying) of the zinc component in the Cu-Zn surface alloys at an appropriate potential (-0.4 V vs. Ag). This dealloying process was found to be highly temperature dependent and surface diffusion controlled, which involved the self-assembly of copper atoms at the alloy/electrolyte interface. Additionally, the effects of the deposition parameters, including deposition temperature, current density as well as total charge density on resulting the microstructure were investigated by scanning electron microscopy, and atomic force microscope.

Effects of metal mining and milling on boundary waters of Yellowstone National Park, USA

USGS Publications Warehouse

Nimmo, D.R.; Willox, M.J.; Lafrancois, T.D.; Chapman, P.L.; Brinkman, S.F.; Greene, J.C.

1998-01-01

Aquatic resources in Soda Butte Creek within Yellowstone National Park, USA, continue to be threatened by heavy metals from historical mining and milling activities that occurred upstream of the park's boundary. This includes the residue of gold, silver, and copper ore mining and processing in the early 1900s near Cooke City, Montana, just downstream of the creek's headwaters. Toxicity tests, using surrogate test species, and analyses of metals in water, sediments, and macroinvertebrate tissue were conducted from 1993 to 1995. Chronic toxicity to test species was greater in the spring than the fall and metal concentrations were elevated in the spring with copper exceeding water quality criteria in 1995. Tests with amphipods using pore water and whole sediment from the creek and copper concentrations in the tissue of macroinvertebrates and fish also suggest that copper is the metal of concern in the watershed. In order to understand current conditions in Soda Butte Creek, heavy metals, especially copper, must be considered important factors in the aquatic and riparian ecosystems within and along the creek extending into Yellowstone National Park.

The effect of red cell and plasma transfusion on serum zinc and copper levels in the neonate.

PubMed

Lockitch, G; Godolphin, W J; Pendray, M R; Quigley, G

1983-11-01

Transfusion of packed red cells (15 to 20 ml/kg) in 11 preterm infants resulted in a slight increase in mean serum zinc levels on the 3rd post transfusion day but no effect was noted on serum copper levels. No significant difference was found between the changes in serum zinc in 141 paired specimens collected a week apart when zero, one, two or three packed cell transfusions were given in the intervening week. A slight decrease in the mean copper level was noted when one transfusion was given. Transfusion of fresh frozen plasma in six newborns with abdominal wall defects resulted in initial serum copper levels two to three times greater than the reference mean for newborns. No effect was noted on zinc levels. Serum copper results should be interpreted with caution in infants who have been transfused with plasma.

Decreased erythrocyte CCS content is a biomarker of copper overload in rats.

PubMed

Bertinato, Jesse; Sherrard, Lindsey; Plouffe, Louise J

2010-07-02

Copper (Cu) is an essential trace metal that is toxic in excess. It is therefore important to be able to accurately assess Cu deficiency or overload. Cu chaperone for Cu/Zn superoxide dismutase (CCS) protein expression is elevated in tissues of Cu-deficient animals. Increased CCS content in erythrocytes is particularly sensitive to decreased Cu status. Given the lack of a non-invasive, sensitive and specific biomarker for the assessment of Cu excess, we investigated whether CCS expression in erythrocytes reflects Cu overload. Rats were fed diets containing normal or high levels of Cu for 13 weeks. Diets contained 6.3 +/- 0.6 (Cu-N), 985 +/- 14 (Cu-1000) or 1944 +/- 19 (Cu-2000) mg Cu/kg diet. Rats showed a variable response to the high Cu diets. Some rats showed severe Cu toxicity, while other rats showed no visible signs of toxicity and grew normally. Also, some rats had high levels of Cu in liver, whereas others had liver Cu concentrations within the normal range. Erythrocyte CCS protein expression was 30% lower in Cu-2000 rats compared to Cu-N rats (P < 0.05). Notably, only rats that accumulated high levels of Cu in liver had lower erythrocyte CCS (47% reduction, P < 0.05) compared to rats fed normal levels of Cu. Together, these data indicate that decreased erythrocyte CCS content is associated with Cu overload in rats and should be evaluated further as a potential biomarker for assessing Cu excess in humans.

Copper Regulates Maturation and Expression of an MITF:Tryptase Axis in Mast Cells.

PubMed

Hu Frisk, Jun Mei; Kjellén, Lena; Kaler, Stephen G; Pejler, Gunnar; Öhrvik, Helena

2017-12-15

Copper has previously been implicated in the regulation of immune responses, but the impact of this metal on mast cells is poorly understood. In this article, we address this issue and show that copper starvation of mast cells causes increased granule maturation, as indicated by higher proteoglycan content, stronger metachromatic staining, and altered ultrastructure in comparison with nontreated cells, whereas copper overload has the opposite effects. In contrast, copper status did not impact storage of histamine in mast cells, nor did alterations in copper levels affect the ability of mast cells to degranulate in response to IgER cross-linking. A striking finding was decreased tryptase content in mast cells with copper overload, whereas copper starvation increased tryptase content. These effects were associated with corresponding shifts in tryptase mRNA levels, suggesting that copper affects tryptase gene regulation. Mechanistically, we found that alterations in copper status affected the expression of microphthalmia-associated transcription factor, a transcription factor critical for driving tryptase expression. We also found evidence supporting the concept that the effects on microphthalmia-associated transcription factor are dependent on copper-mediated modulation of MAPK signaling. Finally, we show that, in MEDNIK syndrome, a condition associated with low copper levels and a hyperallergenic skin phenotype, including pruritis and dermatitis, the number of tryptase-positive mast cells is increased. Taken together, our findings reveal a hitherto unrecognized role for copper in the regulation of mast cell gene expression and maturation. Copyright © 2017 by The American Association of Immunologists, Inc.

Cadmium, copper, iron, and zinc concentrations in kidneys of grey wolves, Canis lupus, from Alaska, Idaho, Montana (USA) and the Northwest Territories (Canada).

PubMed

Hoffmann, S R; Blunck, S A; Petersen, K N; Jones, E M; Koval, J C; Misek, R; Frick, J A; Cluff, H D; Sime, C A; McNay, M; Beckman, K B; Atkinson, M W; Drew, M; Collinge, M D; Bangs, E E; Harper, R G

2010-11-01

Cadmium, copper, iron, and zinc levels were measured in the kidneys of 115 grey wolves (Canis lupus) from Idaho, Montana and Alaska (United States), and from the Northwest Territories (Canada). No significant differences in the levels of iron or copper were observed between locations, but wolf kidneys from more northern locations had significantly higher cadmium levels (Alaska > Northwest Territories > Montana ≈ Idaho), and wolves from Alaska showed significantly higher zinc than other locations. Additionally, female wolves in Alaska had higher iron levels than males, and adult wolves in Montana had higher copper levels than subadults.

The Influence of Marine Microfouling on the Corrosion Behaviour of Passive Materials and Copper Alloys

DTIC Science & Technology

2008-01-02

to organometallic catalysis, acidification of the electrode surface, the combined effects of elevated H20 2 and decreased pH and the production of...Ennoblement in marine waters has been ascribed to depolarization of the oxygen reduction reaction due to organometallic catalysis, acidification of the...organometallic catalysis, acidification of the electrode surface, the combined effects of elevated hydrogen peroxide (H202) and decreased pH and the production

Copper-Catalyzed, Directing Group-Assisted Fluorination of Arene and Heteroarene C-H Bonds

PubMed Central

Truong, Thanh; Klimovica, Kristine; Daugulis, Olafs

2013-01-01

We have developed a method for direct, copper-catalyzed, auxiliary-assisted fluorination of β-sp2 C-H bonds of benzoic acid derivatives and γ-sp2 C-H bonds of α,α-disubstituted benzylamine derivatives. The reaction employs CuI catalyst, AgF fluoride source, and DMF, pyridine, or DMPU solvent at moderately elevated temperatures. Selective mono- or difluorination can be achieved by simply changing reaction conditions. The method shows excellent functional group tolerance and provides a straightforward way for the preparation of ortho-fluorinated benzoic acids. PMID:23758609

Copper alters hypoxia sensitivity and the behavioural emersion response in the amphibious fish Kryptolebias marmoratus.

PubMed

Blewett, Tamzin A; Simon, Robyn A; Turko, Andy J; Wright, Patricia A

2017-08-01

Elevated levels of metals have been reported in mangrove ecosystems worldwide. Mangrove fishes also routinely experience severe environmental stressors, such as hypoxia. In the amphibious fish Kryptolebias marmoratus (mangrove rivulus), a key behavioural response to avoid aquatic stress is to leave water (emersion). We hypothesized that copper (Cu) exposure would increase the sensitivity of this behavioural hypoxia avoidance response due to histopathological effects of Cu on gill structure and function. K. marmoratus were exposed to either control (no added Cu) or Cu (300μg/L) for 96h. Following this period, fish were exposed to an acute hypoxic challenge (decline in dissolved oxygen to ∼0% over 15min), and the emersion response was recorded. Gills were examined for histological changes. Fish exposed to Cu emersed at a higher dissolved oxygen level (7.5±0.6%), relative to the control treatment group (5.8±0.4%). Histological analysis showed that the gill surface area increased and the interlamellar cell mass (ILCM) was reduced following Cu exposure, contrary to our prediction. Overall, these data indicate that Cu induces hypoxia-like changes to gill morphology and increases the sensitivity of the hypoxia emersion response. Copyright © 2017 Elsevier B.V. All rights reserved.

Copper and Zinc Chelation as a Treatment of Alzheimer's Disease

NASA Astrophysics Data System (ADS)

Hodak, Miroslav; Bernholc, Jerry

2014-03-01

Alzheimer's disease (AD) is a neurodegenerative disorder affecting millions of people in the U.S. The cause of the disease remains unknown, but amyloid- β (A β), a short peptide, is considered causal its pathogenesis. At cellular level, AD is characterized by deposits mainly composed of A β that also contain elevated levels of transition metals ions. Targeting metals is a promising new strategy for AD treatment, which uses moderately strong metal chelators to sequester them from A β or the environment. PBT2 is a chelating compound that has been the most promising in clinical trials. In our work, we use computer simulations to investigate complexes of a close analog of PBT2 with Cu2+ and Zn2+ ions. The calculations employ KS/FD DFT method, which combines Kohn-Sham DFT with the frozen-density DFT to achieve efficient description of explicit solvent beyond the first solvation shell. Our work is based on recent experiments and examines both 1:1 and 2:1 chelator-metal stochiometries detected experimentally. The results show that copper attaches more strongly than zinc, find that 1:1 complexes involve water in the first coordination shell and determine which one of several possible 2:1 geometries is the most preferable.

Do cytokines have any role in Wilson's disease?

PubMed Central

Goyal, M K; Sinha, S; Patil, S A; Jayalekshmy, V; Taly, A B

2008-01-01

The aim of this study was to determine the serum cytokine levels in patients with Wilson's disease (WD) and correlate with phenotype, therapeutic status and laboratory data. In this cross-sectional study, the serum levels of cytokines were estimated in 34 patients (M : F, 23 : 11; drug-naive, 11) with WD (mean age: 13·8 ± 8·6 and 19·6 ± 9·03 years) and compared with 30 controls. The following serum cytokines were analysed using enzyme-linked immunosorbent assay: (i) tumour necrosis factor (TNF)-α, (ii) interferon (IFN)-γ, (iii) interleukin (IL)-2, (iv) IL-6 and (v) IL-4. Serum TNF-α (P < 0·001), IFN-γ (P = 0·005) and IL-6 (P < 0·001) were detectable in WD compared with controls. However, serum level elevation of IL-4 (P = 0·49) and IL-2 (P = 0·11), although detectable compared with controls, was statistically insignificant. The disease severity and therapeutic status did not affect the cytokines. Presence of anaemia, leucopenia, thrombocytopenia, pancytopenia and hepatic dysfunction did not influence cytokine levels. There was a significant negative correlation between IL-6 and ceruloplasmin (P = 0·04) and anti-inflammatory cytokines (IL-4) and copper level (P = 0·01). Serum cytokines, both proinflammatory and anti-inflammatory subtypes, were elevated significantly in patients with WD. Further studies would establish their role in its pathogenesis. PMID:18821941

Estimation of copper in saliva and areca nut products and its correlation with histological grades of oral submucous fibrosis.

PubMed

Mohammed, Faraz; Manohar, Vidya; Jose, Maji; Thapasum, Arishiya Fairozekhan; Mohamed, Shamaz; Shamaz, Bibi Halima; D'Souza, Neevan

2015-03-01

The purpose of this study was to estimate the copper levels in saliva of patients with oral submucous fibrosis (OSF) and different areca nut products and its correlation with different histological grades of OSF. The study comprised 60 individuals, 30 OSF patients and 30 non-OSF individuals. Unstimulated whole saliva was collected, and copper analysis was performed using colorimetric method. The commercial areca nut products used by the patients were acquired and subjected to copper analysis through the atomic absorption spectrophotometer method. Oral biopsies were performed for OSF patients for histopathological correlation. The mean salivary copper level was 27.023 μg/dl in OSF patients when compared with 8.393 μg/dl in non-OSF individuals (P < 0.005). The mean copper content in different areca nut products was 13.313 ppm (P < 0.005). Comparison of copper content in different areca nut products with salivary copper levels of OSF patients showed negative correlation (P < 0.853). Comparison of salivary copper levels between different histological grades of OSF yielded a statistically significant association between grades I and III (P < 0.005) and grades II and III OSF (P < 0.019). Comparison of copper content in areca nut products and different histological grades of OSF yielded weak negative statistical correlation (r = -0.116). Despite high copper content in areca nut products, the observations yielded a negative correlation with different histological grades of OSF. This further raises a doubt about the copper content in areca nut as an etiological factor for this crippling disease. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Anaerobic Copper Toxicity and Iron-Sulfur Cluster Biogenesis in Escherichia coli.

PubMed

Tan, Guoqiang; Yang, Jing; Li, Tang; Zhao, Jin; Sun, Shujuan; Li, Xiaokang; Lin, Chuxian; Li, Jianghui; Zhou, Huaibin; Lyu, Jianxin; Ding, Huangen

2017-08-15

While copper is an essential trace element in biology, pollution of groundwater from copper has become a threat to all living organisms. Cellular mechanisms underlying copper toxicity, however, are still not fully understood. Previous studies have shown that iron-sulfur proteins are among the primary targets of copper toxicity in Escherichia coli under aerobic conditions. Here, we report that, under anaerobic conditions, iron-sulfur proteins in E. coli cells are even more susceptible to copper in medium. Whereas addition of 0.2 mM copper(II) chloride to LB (Luria-Bertani) medium has very little or no effect on iron-sulfur proteins in wild-type E. coli cells under aerobic conditions, the same copper treatment largely inactivates iron-sulfur proteins by blocking iron-sulfur cluster biogenesis in the cells under anaerobic conditions. Importantly, proteins that do not have iron-sulfur clusters (e.g., fumarase C and cysteine desulfurase) in E. coli cells are not significantly affected by copper treatment under aerobic or anaerobic conditions, indicating that copper may specifically target iron-sulfur proteins in cells. Additional studies revealed that E. coli cells accumulate more intracellular copper under anaerobic conditions than under aerobic conditions and that the elevated copper content binds to the iron-sulfur cluster assembly proteins IscU and IscA, which effectively inhibits iron-sulfur cluster biogenesis. The results suggest that the copper-mediated inhibition of iron-sulfur proteins does not require oxygen and that iron-sulfur cluster biogenesis is the primary target of anaerobic copper toxicity in cells. IMPORTANCE Copper contamination in groundwater has become a threat to all living organisms. However, cellular mechanisms underlying copper toxicity have not been fully understood up to now. The work described here reveals that iron-sulfur proteins in Escherichia coli cells are much more susceptible to copper in medium under anaerobic conditions than they are under aerobic conditions. Under anaerobic conditions, E. coli cells accumulate excess intracellular copper, which specifically targets iron-sulfur proteins by blocking iron-sulfur cluster biogenesis. Since iron-sulfur proteins are involved in diverse and vital physiological processes, inhibition of iron-sulfur cluster biogenesis by copper disrupts multiple cellular functions and ultimately inhibits cell growth. The results from this study illustrate a new interplay between intracellular copper toxicity and iron-sulfur cluster biogenesis in bacterial cells under anaerobic conditions. Copyright © 2017 American Society for Microbiology.

Anaerobic Copper Toxicity and Iron-Sulfur Cluster Biogenesis in Escherichia coli

PubMed Central

Tan, Guoqiang; Yang, Jing; Li, Tang; Zhao, Jin; Sun, Shujuan; Li, Xiaokang; Lin, Chuxian; Li, Jianghui; Zhou, Huaibin

2017-01-01

ABSTRACT While copper is an essential trace element in biology, pollution of groundwater from copper has become a threat to all living organisms. Cellular mechanisms underlying copper toxicity, however, are still not fully understood. Previous studies have shown that iron-sulfur proteins are among the primary targets of copper toxicity in Escherichia coli under aerobic conditions. Here, we report that, under anaerobic conditions, iron-sulfur proteins in E. coli cells are even more susceptible to copper in medium. Whereas addition of 0.2 mM copper(II) chloride to LB (Luria-Bertani) medium has very little or no effect on iron-sulfur proteins in wild-type E. coli cells under aerobic conditions, the same copper treatment largely inactivates iron-sulfur proteins by blocking iron-sulfur cluster biogenesis in the cells under anaerobic conditions. Importantly, proteins that do not have iron-sulfur clusters (e.g., fumarase C and cysteine desulfurase) in E. coli cells are not significantly affected by copper treatment under aerobic or anaerobic conditions, indicating that copper may specifically target iron-sulfur proteins in cells. Additional studies revealed that E. coli cells accumulate more intracellular copper under anaerobic conditions than under aerobic conditions and that the elevated copper content binds to the iron-sulfur cluster assembly proteins IscU and IscA, which effectively inhibits iron-sulfur cluster biogenesis. The results suggest that the copper-mediated inhibition of iron-sulfur proteins does not require oxygen and that iron-sulfur cluster biogenesis is the primary target of anaerobic copper toxicity in cells. IMPORTANCE Copper contamination in groundwater has become a threat to all living organisms. However, cellular mechanisms underlying copper toxicity have not been fully understood up to now. The work described here reveals that iron-sulfur proteins in Escherichia coli cells are much more susceptible to copper in medium under anaerobic conditions than they are under aerobic conditions. Under anaerobic conditions, E. coli cells accumulate excess intracellular copper, which specifically targets iron-sulfur proteins by blocking iron-sulfur cluster biogenesis. Since iron-sulfur proteins are involved in diverse and vital physiological processes, inhibition of iron-sulfur cluster biogenesis by copper disrupts multiple cellular functions and ultimately inhibits cell growth. The results from this study illustrate a new interplay between intracellular copper toxicity and iron-sulfur cluster biogenesis in bacterial cells under anaerobic conditions. PMID:28576762

Low copper and high manganese levels in prion protein plaques

USGS Publications Warehouse

Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecth, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; McKenzie, Debbie

2013-01-01

Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

Polyelectrolyte-mediated assembly of copper-phthalocyanine tetrasulfonate multilayers and the subsequent production of nanoparticulate copper oxide thin films.

PubMed

Chickneyan, Zarui Sara; Briseno, Alejandro L; Shi, Xiangyang; Han, Shubo; Huang, Jiaxing; Zhou, Feimeng

2004-07-01

An approach to producing films of nanometer-sized copper oxide particulates, based on polyelectrolyte-mediated assembly of the precursor, copper(II)phthalocyanine tetrasulfonate (CPTS), is described. Multilayered CPTS and polydiallyldimethylammonium chloride (PDADMAC) were alternately assembled on different planar substrates via the layer-by-layer (LbL) procedure. The growth of CPTS multilayers was monitored by UV-visible spectrometry and quartz crystal microbalance (QCM) measurements. Both the UV-visible spectra and the QCM data showed that a fixed amount of CPTS could be attached to the substrate surface for a given adsorption cycle. Cyclic voltammograms at the CPTS/PDADMAC-covered gold electrode exhibited a decrease in peak currents with the layer number, indicating that the permeability of CPTS multilayers on the electrodes had diminished. When these CPTS multilayered films were calcined at elevated temperatures, uniform thin films composed of nanoparticulate copper oxide could be produced. Ellipsometry showed that the thickness of copper oxide nanoparticulate films could be precisely tailored by varying the thickness of CPTS multilayer films. The morphology and roughness of CPTS multilayer and copper oxide thin films were characterized by atomic force microscopy. X-ray diffraction (XRD) measurements indicated that these thin films contained both CuO and Cu2O nanoparticles. The preparation of such copper oxide thin films with the use of metal complex precursors represents a new route for the synthesis of inorganic oxide films with a controlled thickness.

The Features of Copper Metabolism in the Rat Liver during Development

PubMed Central

2015-01-01

Strong interest in copper homeostasis is due to the fact that copper is simultaneously a catalytic co-factor of the vital enzymes, a participant in signaling, and a toxic agent provoking oxidative stress. In mammals, during development copper metabolism is conformed to two types. In embryonic type copper metabolism (ETCM), newborns accumulate copper to high level in the liver because its excretion via bile is blocked; and serum copper concentration is low because ceruloplasmin (the main copper-containing protein of plasma) gene expression is repressed. In the late weaning, the ETCM switches to the adult type copper metabolism (ATCM), which is manifested by the unlocking of copper excretion and the induction of ceruloplasmin gene activity. The considerable progress has been made in the understanding of the molecular basis of copper metabolic turnover in the ATCM, but many aspects of the copper homeostasis in the ETCM remain unclear. The aim of this study was to investigate the copper metabolism during transition from the ETCM (up to 12-days-old) to the ATCM in the rats. It was shown that in the liver, copper was accumulated in the nuclei during the first 5 days of life, and then it was re-located to the mitochondria. In parallel with the mitochondria, copper bulk bound with cytosolic metallothionein was increased. All compartments of the liver cells rapidly lost most of their copper on the 13th day of life. In newborns, serum copper concentration was low, and its major fraction was associated with holo-Cp, however, a small portion of copper was bound to extracellular metallothionein and a substance that was slowly eluted during gel-filtration. In adults, serum copper concentration increased by about a factor of 3, while metallothionein-bound copper level decreased by a factor of 2. During development, the expression level of Cp, Sod1, Cox4i1, Atp7b, Ctr1, Ctr2, Cox17, and Ccs genes was significantly increased, and metallothionein was decreased. Atp7a gene’s activity was fully repressed. The copper routes in newborns are discussed. PMID:26474410

Combining -Omics to Unravel the Impact of Copper Nutrition on Alfalfa (Medicago sativa) Stem Metabolism.

PubMed

Printz, Bruno; Guerriero, Gea; Sergeant, Kjell; Audinot, Jean-Nicolas; Guignard, Cédric; Renaut, Jenny; Lutts, Stanley; Hausman, Jean-Francois

2016-02-01

Copper can be found in the environment at concentrations ranging from a shortage up to the threshold of toxicity for plants, with optimal growth conditions situated in between. The plant stem plays a central role in transferring and distributing minerals, water and other solutes throughout the plant. In this study, alfalfa is exposed to different levels of copper availability, from deficiency to slight excess, and the impact on the metabolism of the stem is assessed by a non-targeted proteomics study and by the expression analysis of key genes controlling plant stem development. Under copper deficiency, the plant stem accumulates specific copper chaperones, the expression of genes involved in stem development is decreased and the concentrations of zinc and molybdenum are increased in comparison with the optimum copper level. At the optimal copper level, the expression of cell wall-related genes increases and proteins playing a role in cell wall deposition and in methionine metabolism accumulate, whereas copper excess imposes a reduction in the concentration of iron in the stem and a reduced abundance of ferritins. Secondary ion mass spectrometry (SIMS) analysis suggests a role for the apoplasm as a copper storage site in the case of copper toxicity. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

Combining -Omics to Unravel the Impact of Copper Nutrition on Alfalfa (Medicago sativa) Stem Metabolism

PubMed Central

Printz, Bruno; Guerriero, Gea; Sergeant, Kjell; Audinot, Jean-Nicolas; Guignard, Cédric; Renaut, Jenny; Lutts, Stanley; Hausman, Jean-Francois

2016-01-01

Copper can be found in the environment at concentrations ranging from a shortage up to the threshold of toxicity for plants, with optimal growth conditions situated in between. The plant stem plays a central role in transferring and distributing minerals, water and other solutes throughout the plant. In this study, alfalfa is exposed to different levels of copper availability, from deficiency to slight excess, and the impact on the metabolism of the stem is assessed by a non-targeted proteomics study and by the expression analysis of key genes controlling plant stem development. Under copper deficiency, the plant stem accumulates specific copper chaperones, the expression of genes involved in stem development is decreased and the concentrations of zinc and molybdenum are increased in comparison with the optimum copper level. At the optimal copper level, the expression of cell wall-related genes increases and proteins playing a role in cell wall deposition and in methionine metabolism accumulate, whereas copper excess imposes a reduction in the concentration of iron in the stem and a reduced abundance of ferritins. Secondary ion mass spectrometry (SIMS) analysis suggests a role for the apoplasm as a copper storage site in the case of copper toxicity. PMID:26865661

Synthesis of cytochrome c oxidase 1 (SCO1) inhibits insulin sensitivity by decreasing copper levels in adipocytes.

PubMed

Wei, Xiang-Bo; Guo, Liang; Liu, Yang; Zhou, Shui-Rong; Liu, Yuan; Dou, Xin; Du, Shao-Yue; Ding, Meng; Peng, Wan-Qiu; Qian, Shu-Wen; Huang, Hai-Yan; Tang, Qi-Qun

2017-09-23

Dysregulation of insulin signaling leads to type 2 diabetes mellitus (T2DM) and other metabolic disorders. Obesity is an important contributor to insulin resistance, and although the understanding of this relationship has improved in recent years, the mechanism of obesity-induced insulin resistance is not completely understood. Disorders of copper metabolism tend to accompany the development of obesity, which increases the risk of insulin resistance. Synthesis of cytochrome c oxidase 1 (SCO1) functions in the assembly of cytochrome c oxidase (COX) and cellular copper homeostasis. However, the role of SCO1 in the regulation of metabolism remains unknown. Here, we found that obese mice had higher expression of SCO1 and lower levels of copper in white adipose tissue (WAT) than did the control mice. Overexpression of SCO1 in adipocytes was associated with copper deficiency. Copper increased insulin sensitivity by decreasing the level of phosphatase and tensin homolog (PTEN) protein. Ectopic expression of SCO1 led to insulin resistance and was accompanied by a decrease in intracellular copper level, and addition of copper abolished the inhibitory effect of SCO1 on insulin sensitivity. Our results demonstrated a novel role of SCO1 in modulating insulin sensitivity via the regulation of copper concentration in WAT and suggested a potential therapeutic target for T2DM. Copyright © 2017. Published by Elsevier Inc.

Copper Deficiency Leads to Anemia, Duodenal Hypoxia, Upregulation of HIF-2α and Altered Expression of Iron Absorption Genes in Mice

PubMed Central

Matak, Pavle; Zumerle, Sara; Mastrogiannaki, Maria; El Balkhi, Souleiman; Delga, Stephanie; Mathieu, Jacques R. R.; Canonne-Hergaux, François; Poupon, Joel; Sharp, Paul A.; Vaulont, Sophie; Peyssonnaux, Carole

2013-01-01

Iron and copper are essential trace metals, actively absorbed from the proximal gut in a regulated fashion. Depletion of either metal can lead to anemia. In the gut, copper deficiency can affect iron absorption through modulating the activity of hephaestin - a multi-copper oxidase required for optimal iron export from enterocytes. How systemic copper status regulates iron absorption is unknown. Mice were subjected to a nutritional copper deficiency-induced anemia regime from birth and injected with copper sulphate intraperitoneally to correct the anemia. Copper deficiency resulted in anemia, increased duodenal hypoxia and Hypoxia inducible factor 2α (HIF-2α) levels, a regulator of iron absorption. HIF-2α upregulation in copper deficiency appeared to be independent of duodenal iron or copper levels and correlated with the expression of iron transporters (Ferroportin - Fpn, Divalent Metal transporter – Dmt1) and ferric reductase – Dcytb. Alleviation of copper-dependent anemia with intraperitoneal copper injection resulted in down regulation of HIF-2α-regulated iron absorption genes in the gut. Our work identifies HIF-2α as an important regulator of iron transport machinery in copper deficiency. PMID:23555700

Speeding up solar disinfection (SODIS): effects of hydrogen peroxide, temperature, pH, and copper plus ascorbate on the photoinactivation of E. coli.

PubMed

Fisher, Michael B; Keenan, Christina R; Nelson, Kara L; Voelker, Bettina M

2008-03-01

Solar disinfection, or SODIS, shows tremendous promise for point-of-use drinking water treatment in developing countries, but can require 48 h or more for adequate disinfection in cloudy weather. In this research, we show that a number of low-cost additives are capable of accelerating SODIS. These additives included 100-1000 muM hydrogen peroxide, both at room temperature and at elevated temperatures, 0.5 - 1% lemon and lime juice, and copper metal or aqueous copper plus ascorbate, with or without hydrogen peroxide. Laboratory and field experiments indicated that additives might make SODIS more rapid and effective in both sunny and cloudy weather, developments that could help make the technology more effective and acceptable to users.

The Intestinal Copper Exporter CUA-1 Is Required for Systemic Copper Homeostasis in Caenorhabditis elegans*♦

PubMed Central

Chun, Haarin; Sharma, Anuj Kumar; Lee, Jaekwon; Chan, Jefferson; Jia, Shang; Kim, Byung-Eun

2017-01-01

Copper plays key catalytic and regulatory roles in biochemical processes essential for normal growth, development, and health. Defects in copper metabolism cause Menkes and Wilson's disease, myeloneuropathy, and cardiovascular disease and are associated with other pathophysiological states. Consequently, it is critical to understand the mechanisms by which organisms control the acquisition, distribution, and utilization of copper. The intestinal enterocyte is a key regulatory point for copper absorption into the body; however, the mechanisms by which intestinal cells transport copper to maintain organismal copper homeostasis are poorly understood. Here, we identify a mechanism by which organismal copper homeostasis is maintained by intestinal copper exporter trafficking that is coordinated with extraintestinal copper levels in Caenorhabditis elegans. Specifically, we show that CUA-1, the C. elegans homolog of ATP7A/B, localizes to lysosome-like organelles (gut granules) in the intestine under copper overload conditions for copper detoxification, whereas copper deficiency results in a redistribution of CUA-1 to basolateral membranes for copper efflux to peripheral tissues. Worms defective in gut granule biogenesis exhibit defects in copper sequestration and increased susceptibility to toxic copper levels. Interestingly, however, a splice isoform CUA-1.2 that lacks a portion of the N-terminal domain is targeted constitutively to the basolateral membrane irrespective of dietary copper concentration. Our studies establish that CUA-1 is a key intestinal copper exporter and that its trafficking is regulated to maintain systemic copper homeostasis. C. elegans could therefore be exploited as a whole-animal model system to study regulation of intra- and intercellular copper trafficking pathways. PMID:27881675

Earth Observations taken by the Expedition 18 Crew

NASA Image and Video Library

2008-10-24

ISS018-E-005353 (24 Oct. 2008) --- Breckenridge and Copper Mountain ski slopes, Colorado are featured in this image photographed by an Expedition 18 crewmember on the International Space Station. Located in a section of the Rocky Mountains which extend through central Colorado, Tenmile Range and Copper Mountain provide the ideal location and landscape for popular winter sports. In this view, the Breckenridge and Copper Mountain ski areas are clearly visible as the snow covered ski runs stand out among the surrounding darker forest. Tenmile Range has mountain peaks that are named Peaks 1 through Peaks 10. The Breckenridge ski area use Peaks 7 through Peaks 10 which range from 12,631 feet (3,850 meters) to 13,615 feet (4,150 meters) high. Tenmile Canyon is a north northeast-trending fault-controlled valley running nearly 3,000 feet (914.4 meters) deep that serves as the boundaries for Tenmile Creek running through the center of the photo. The snow-covered peaks clearly delineate the tree line at an elevation of around 11,000 feet (3,350 meters). In the winter, this area's annual average snowfall ranges between 284 inches (7.21 meters) at Copper Mountain to 300 inches (7.62 meters) a year at Breckenridge. Before recreation became the main industry, miners were attracted to the area in the mid-1800's following discoveries of gold, silver, lead, and zinc. The towns of Breckenridge and Wheeler Junction (at the base of Copper Mountain ski area) were born out of the surge to settle the West during the Pike's Peak Gold Rush. While this image records snow on the peaks of Tenmile Range, the months of October and November 2008 saw little accumulation of snow pack in the area of Breckenridge. The situation changed in early December 2008 however, when more snow fell in eight days than in the preceding two months. The late, but significant, snowfall boosted the snow pack back to expected levels for this time of year.

Zinc and Copper Differentially Modulate Amyloid Precursor Protein Processing by γ-Secretase and Amyloid-β Peptide Production.

PubMed

Gerber, Hermeto; Wu, Fang; Dimitrov, Mitko; Garcia Osuna, Guillermo M; Fraering, Patrick C

2017-03-03

Recent evidence suggests involvement of biometal homeostasis in the pathological mechanisms in Alzheimer's disease (AD). For example, increased intracellular copper or zinc has been linked to a reduction in secreted levels of the AD-causing amyloid-β peptide (Aβ). However, little is known about whether these biometals modulate the generation of Aβ. In the present study we demonstrate in both cell-free and cell-based assays that zinc and copper regulate Aβ production by distinct molecular mechanisms affecting the processing by γ-secretase of its Aβ precursor protein substrate APP-C99. We found that Zn 2+ induces APP-C99 dimerization, which prevents its cleavage by γ-secretase and Aβ production, with an IC 50 value of 15 μm Importantly, at this concentration, Zn 2+ also drastically raised the production of the aggregation-prone Aβ43 found in the senile plaques of AD brains and elevated the Aβ43:Aβ40 ratio, a promising biomarker for neurotoxicity and AD. We further demonstrate that the APP-C99 histidine residues His-6, His-13, and His-14 control the Zn 2+ -dependent APP-C99 dimerization and inhibition of Aβ production, whereas the increased Aβ43:Aβ40 ratio is substrate dimerization-independent and involves the known Zn 2+ binding lysine Lys-28 residue that orientates the APP-C99 transmembrane domain within the lipid bilayer. Unlike zinc, copper inhibited Aβ production by directly targeting the subunits presenilin and nicastrin in the γ-secretase complex. Altogether, our data demonstrate that zinc and copper differentially modulate Aβ production. They further suggest that dimerization of APP-C99 or the specific targeting of individual residues regulating the production of the long, toxic Aβ species, may offer two therapeutic strategies for preventing AD. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Progesterone, selected heavy metals and micronutrients in pregnant Nigerian women with a history of recurrent spontaneous abortion.

PubMed

Ajayi, O O; Charles-Davies, M A; Arinola, O G

2012-06-01

Environmental and endocrine factors have been implicated in the aetiology of recurrent abortion, with poorly understood roles. Luteal phase insufficiency marked with insufficient progesterone secretion has been reported. To define the involvement of progesterone, trace metals, and Vitamin E in pregnant women with history of recurrent spontaneous abortion. Convenience sampling method was used to recruit 69 pregnant women aged 21-41 years with gestational age of 0-20 weeks in this case-control study. Thirty five (cases) and thirty four (controls) had previous and no history of recurrent spontaneous abortion respectively. Demographic characteristics and 10 mls of blood samples were obtained from each subject. Serum obtained was used for the determination of progesterone, zinc, copper, selenium, iron, magnesium, manganese, chromium, lead, cadmium, and serum vitamin E by standard methods. Results showed statistically significant decreases (p<0.05) in the serum zinc, copper, and vitamin E and a significant elevation (p<0.05) in the serum selenium, lead, and cadmium in cases compared with controls. Insignificant decrease (p=0.07) was observed in the serum progesterone when cases were compared with controls. Results suggest that elevated serum heavy metals (cadmium and lead) and reduction of essential micronutrients (zinc, copper and vitamin E) may contribute to recurrent spontaneous abortion.

Response to excess copper in the hyperthermophile Sulfolobus solfataricus strain 98/2

PubMed Central

Villafane, Aramis; Voskoboynik, Yekaterina; Cuebas, Mariola; Ruhl, Ilona; Bini, Elisabetta

2009-01-01

Copper is an essential micronutrient, but toxic in excess. Sulfolobus solfataricus cells have the ability to adapt to fluctuations of copper levels in their external environment. To better understand the molecular mechanism behind the organismal response to copper, the expression of the cluster of genes copRTA, which encodes the copper-responsive transcriptional regulator CopR, the copper-binding protein CopT, and CopA, has been investigated and the whole operon has been shown to be cotranscribed at low levels from the copR promoter under all conditions, whereas increased transcription from the copTA promoter occurs in the presence of excess copper. Furthermore, the expression of the copper-transporting ATPase CopA over a 27-hour interval has been monitored by quantitative real-time RT-PCR and compared to the pattern of cellular copper accumulation, as determined in a parallel analysis by Inductively Coupled Plasma Optical Emission spectrometry (ICP-OES). The results provide the basis for a model of the molecular mechanisms of copper homeostasis in Sulfolobus, which relies on copper efflux and sequestration. PMID:19427833

iron phase control during pressure leaching at elevated temperature

NASA Astrophysics Data System (ADS)

Fleuriault, Camille

Iron is a common contaminant encountered in most metal recovery operations, and particularly hydrometallurgical processes. For example, the Hematite Process uses autoclaves to precipitate iron oxide out of the leaching solution, while other metals are solubilized for further hydrometallurgical processing. In some cases, Basic Iron Sulfate (BIS) forms in place of hematite. The presence of BIS is unwanted in the autoclave discharge because it diminishes recovery and causes environmental matters. The focus of this master thesis is on the various iron phases forming during the pressure oxidation of sulfates. Artificial leaching solutions were produced from CuSO4, FeSO4 and H2SO4 in an attempt to recreate the matrix composition and conditions used for copper sulfides autoclaving. The following factors were investigated in order to determine which conditions hinder the formation of BIS: initial free acidity (5 -- 98 g/L), initial copper concentration (12.7 -- 63.5 g/L), initial iron concentration (16.7 -- 30.7 g/L) and initial iron oxidation state. There were three solid species formed in the autoclave: hematite, BIS and hydronium jarosite. The results show that free acid is the main factor influencing the composition of the residue. At an initial concentration of 22.3 g/L iron and no copper added, the upper limit for iron oxide formation is 41 g/L H2SO4. The increase of BIS content in the residue is not gradual and occurs over a change of a few grams per liter around the aforementioned limit. Increasing copper sulfate concentration in the solution hinders the formation of BIS. At 63.5g/L copper, the upper free acidity limit is increased to 61g/L. This effect seems to be related to the buffering action of copper sulfate, decreasing the overall acid concentration and thus extending the stability range of hematite. The effect of varying iron concentration on the precipitate chemistry is unclear. At high iron levels, the only noticeable effect was the inhibition of jarosite. The results were reported within a Cu-Fe-S ternary system and modeled. The modeling confirmed the experimental observations with the exception that increasing iron concentrations seem to promote BIS stability.

Hydrogenation of CO 2 on ZnO/Cu(100) and ZnO/Cu(111) Catalysts: Role of Copper Structure and Metal–Oxide Interface in Methanol Synthesis

DOE PAGES

Palomino, Robert M.; Ramirez, Pedro J.; Liu, Zongyuan; ...

2017-08-21

The results of kinetic tests and ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) show the important role played by a ZnO–copper interface in the generation of CO and the synthesis of methanol from CO 2 hydrogenation. The deposition of nanoparticles of ZnO on Cu(100) and Cu(111), θ oxi < 0.3 monolayer, produces highly active catalysts. The catalytic activity of these systems increases in the sequence: Cu(111) < Cu(100) < ZnO/Cu(111) < ZnO/Cu(100). The structure of the copper substrate influences the catalytic performance of a ZnO–copper interface. Furthermore, size and metal–oxide interactions affect the chemical and catalytic properties of the oxide making themore » supported nanoparticles different from bulk ZnO. The formation of a ZnO–copper interface favors the binding and conversion of CO 2 into a formate intermediate that is stable on the catalyst surface up to temperatures above 500 K. Alloys of Zn with Cu(111) and Cu(100) were not stable at the elevated temperatures (500–600 K) used for the CO 2 hydrogenation reaction. However, reaction with CO 2 oxidized the zinc, enhancing its stability over the copper substrates.« less

Hydrogenation of CO 2 on ZnO/Cu(100) and ZnO/Cu(111) Catalysts: Role of Copper Structure and Metal–Oxide Interface in Methanol Synthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palomino, Robert M.; Ramirez, Pedro J.; Liu, Zongyuan

The results of kinetic tests and ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) show the important role played by a ZnO–copper interface in the generation of CO and the synthesis of methanol from CO 2 hydrogenation. The deposition of nanoparticles of ZnO on Cu(100) and Cu(111), θ oxi < 0.3 monolayer, produces highly active catalysts. The catalytic activity of these systems increases in the sequence: Cu(111) < Cu(100) < ZnO/Cu(111) < ZnO/Cu(100). The structure of the copper substrate influences the catalytic performance of a ZnO–copper interface. Furthermore, size and metal–oxide interactions affect the chemical and catalytic properties of the oxide making themore » supported nanoparticles different from bulk ZnO. The formation of a ZnO–copper interface favors the binding and conversion of CO 2 into a formate intermediate that is stable on the catalyst surface up to temperatures above 500 K. Alloys of Zn with Cu(111) and Cu(100) were not stable at the elevated temperatures (500–600 K) used for the CO 2 hydrogenation reaction. However, reaction with CO 2 oxidized the zinc, enhancing its stability over the copper substrates.« less

Copper Tolerance and Biosorption of Saccharomyces cerevisiae during Alcoholic Fermentation

PubMed Central

Liu, Ling-ling; Jia, Bo; Zhao, Fang; Huang, Wei-dong; Zhan, Ji-cheng

2015-01-01

At high levels, copper in grape mash can inhibit yeast activity and cause stuck fermentations. Wine yeast has limited tolerance of copper and can reduce copper levels in wine during fermentation. This study aimed to understand copper tolerance of wine yeast and establish the mechanism by which yeast decreases copper in the must during fermentation. Three strains of Saccharomyces cerevisiae (lab selected strain BH8 and industrial strains AWRI R2 and Freddo) and a simple model fermentation system containing 0 to 1.50 mM Cu2+ were used. ICP-AES determined Cu ion concentration in the must decreasing differently by strains and initial copper levels during fermentation. Fermentation performance was heavily inhibited under copper stress, paralleled a decrease in viable cell numbers. Strain BH8 showed higher copper-tolerance than strain AWRI R2 and higher adsorption than Freddo. Yeast cell surface depression and intracellular structure deformation after copper treatment were observed by scanning electron microscopy and transmission electron microscopy; electronic differential system detected higher surface Cu and no intracellular Cu on 1.50 mM copper treated yeast cells. It is most probably that surface adsorption dominated the biosorption process of Cu2+ for strain BH8, with saturation being accomplished in 24 h. This study demonstrated that Saccharomyces cerevisiae strain BH8 has good tolerance and adsorption of Cu, and reduces Cu2+ concentrations during fermentation in simple model system mainly through surface adsorption. The results indicate that the strain selected from China’s stress-tolerant wine grape is copper tolerant and can reduce copper in must when fermenting in a copper rich simple model system, and provided information for studies on mechanisms of heavy metal stress. PMID:26030864

Low-dose copper infusion into the coronary circulation induces acute heart failure in diabetic rats: New mechanism of heart disease.

PubMed

Cheung, Carlos Chun Ho; Soon, Choong Yee; Chuang, Chia-Lin; Phillips, Anthony R J; Zhang, Shaoping; Cooper, Garth J S

2015-09-01

Diabetes impairs copper (Cu) regulation, causing elevated serum Cu and urinary Cu excretion in patients with established cardiovascular disease; it also causes cardiomyopathy and chronic cardiac impairment linked to defective Cu homeostasis in rats. However, the mechanisms that link impaired Cu regulation to cardiac dysfunction in diabetes are incompletely understood. Chronic treatment with triethylenetetramine (TETA), a Cu²⁺-selective chelator, improves cardiac function in diabetic patients, and in rats with heart disease; the latter displayed ∼3-fold elevations in free Cu²⁺ in the coronary effluent when TETA was infused into their coronary arteries. To further study the nature of defective cardiac Cu regulation in diabetes, we employed an isolated-perfused, working-heart model in which we infused micromolar doses of Cu²⁺ into the coronary arteries and measured acute effects on cardiac function in diabetic and non-diabetic-control rats. Infusion of CuCl₂ solutions caused acute dose-dependent cardiac dysfunction in normal hearts. Several measures of baseline cardiac function were impaired in diabetic hearts, and these defects were exacerbated by low-micromolar Cu²⁺ infusion. The response to infused Cu²⁺ was augmented in diabetic hearts, which became defective at lower infusion levels and underwent complete pump failure (cardiac output = 0 ml/min) more often (P < 0.0001) at concentrations that only moderately impaired function of control hearts. To our knowledge, this is the first report describing the acute effects on cardiac function of pathophysiological elevations in coronary Cu²⁺. The effects of Cu²⁺ infusion occur within minutes in both control and diabetic hearts, which suggests that they are not due to remodelling. Heightened sensitivity to the acute effects of small elevations in Cu²⁺ could contribute substantively to impaired cardiac function in patients with diabetes and is thus identified as a new mechanism of heart disease. Copyright © 2015 Elsevier Inc. All rights reserved.

The prevalence of low serum zinc and copper levels and dietary habits associated with serum zinc and copper in 12- to 36-month-old children from low-income families at risk for iron deficiency.

PubMed

Schneider, Julie M; Fujii, Mary L; Lamp, Catherine L; Lönnerdal, Bo; Zidenberg-Cherr, Sheri

2007-11-01

Iron and zinc share common food sources, and children at risk of iron deficiency may also develop zinc deficiency. We determined the prevalence of zinc and copper deficiency and examined factors associated with serum zinc and copper in young children from low-income families at risk of iron deficiency. A cross-sectional study design was used to assess serum zinc and copper, along with an interview-assisted survey to assess factors associated with serum zinc and copper in a convenience sample. Participants were 435 children aged 12 to 36 months recruited from select clinics of the Special Supplemental Nutrition Program for Women, Infants, and Children in Contra Costa and Tulare Counties, California. Frequencies were used to report prevalence. Multiple linear regressions were conducted to examine factors associated with serum zinc and copper, controlling for age, sex, and ethnicity. The prevalence of low serum zinc level (<70 microg/dL [<10.7 micromol/L]) was 42.8%, and low serum copper level (<90 microg/dL [<14.2 micromol/L]) was <1%. Mean+/-standard deviation of serum copper was 150+/-22 microg/dL (23.6+/-3.5 micromol/L) and 140+/-24 microg/dL (22.1+/-3.8 micromol/L) for anemic and non-anemic children, respectively (t test, P=0.026). In multiple linear regression consumption of sweetened beverages was negatively associated with serum zinc level, and consumption of >15 g/day meat was positively associated with serum zinc level, whereas current consumption of breast milk and >15 g/day beans were positively associated with serum copper level. The prevalence of low serum zinc concentration in the sample was high, and warrants further investigation amongst vulnerable populations.

How do anthropogenic contaminants (ACs) affect behaviour? Multi-level analysis of the effects of copper on boldness in hermit crabs.

PubMed

White, Stephen J; Briffa, Mark

2017-02-01

Natural animal populations are increasingly exposed to human impacts on the environment, which could have consequences for their behaviour. Among these impacts is exposure to anthropogenic contaminants. Any environmental variable that influences internal state could impact behaviour across a number of levels: at the sample mean, at the level of among-individual differences in behaviour ('animal personality') and at the level of within-individual variation in behaviour (intra-individual variation, 'IIV'). Here we examined the effect of exposure to seawater-borne copper on the startle response behaviour of European hermit crabs, Pagurus bernhardus across these levels. Copper exposure rapidly led to longer startle responses on average, but did not lead to any change in repeatability indicating that individual differences were present and equally consistent in the presence and absence of copper. There was no strong evidence that copper exposure led to changes in IIV. Our data show that exposure to copper for 1 week produces sample mean level changes in the behaviour of hermit crabs. However, there is no evidence that this exposure led to changes in repeatability through feedback loops.

Pre-diagnostic copper and zinc biomarkers and colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition cohort.

PubMed

Stepien, Magdalena; Jenab, Mazda; Freisling, Heinz; Becker, Niels-Peter; Czuban, Magdalena; Tjønneland, Anne; Olsen, Anja; Overvad, Kim; Boutron-Ruault, Marie-Christine; Mancini, Francesca Romana; Savoye, Isabelle; Katzke, Verena; Kühn, Tilman; Boeing, Heiner; Iqbal, Khalid; Trichopoulou, Antonia; Bamia, Christina; Orfanos, Philippos; Palli, Domenico; Sieri, Sabina; Tumino, Rosario; Naccarati, Alessio; Panico, Salvatore; Bueno-de-Mesquita, H B As; Peeters, Petra H; Weiderpass, Elisabete; Merino, Susana; Jakszyn, Paula; Sanchez, Maria-Jose; Dorronsoro, Miren; Huerta, José María; Barricarte, Aurelio; Boden, Stina; van Guelpen, Behany; Wareham, Nick; Khaw, Kay-Tee; Bradbury, Kathryn E; Cross, Amanda J; Schomburg, Lutz; Hughes, David J

2017-07-01

Adequate intake of copper and zinc, two essential micronutrients, are important for antioxidant functions. Their imbalance may have implications for development of diseases like colorectal cancer (CRC), where oxidative stress is thought to be etiologically involved. As evidence from prospective epidemiologic studies is lacking, we conducted a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort to investigate the association between circulating levels of copper and zinc, and their calculated ratio, with risk of CRC development. Copper and zinc levels were measured by reflection X-ray fluorescence spectrometer in 966 cases and 966 matched controls. Multivariable adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated using conditional logistic regression and are presented for the fifth versus first quintile. Higher circulating concentration of copper was associated with a raised CRC risk (OR = 1.50; 95% CI: 1.06, 2.13; P-trend = 0.02) whereas an inverse association with cancer risk was observed for higher zinc levels (OR = 0.65; 95% CI: 0.43, 0.97; P-trend = 0.07). Consequently, the ratio of copper/zinc was positively associated with CRC (OR = 1.70; 95% CI: 1.20, 2.40; P-trend = 0.0005). In subgroup analyses by follow-up time, the associations remained statistically significant only in those diagnosed within 2 years of blood collection. In conclusion, these data suggest that copper or copper levels in relation to zinc (copper to zinc ratio) become imbalanced in the process of CRC development. Mechanistic studies into the underlying mechanisms of regulation and action are required to further examine a possible role for higher copper and copper/zinc ratio levels in CRC development and progression. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Cytoplasmic CopZ-Like Protein and Periplasmic Rusticyanin and AcoP Proteins as Possible Copper Resistance Determinants in Acidithiobacillus ferrooxidans ATCC 23270

PubMed Central

Navarro, Claudio A.; von Bernath, Diego; Martínez-Bussenius, Cristóbal; Castillo, Rodrigo A.

2015-01-01

Acidophilic organisms, such as Acidithiobacillus ferrooxidans, possess high-level resistance to copper and other metals. A. ferrooxidans contains canonical copper resistance determinants present in other bacteria, such as CopA ATPases and RND efflux pumps, but these components do not entirely explain its high metal tolerance. The aim of this study was to find other possible copper resistance determinants in this bacterium. Transcriptional expression of A. ferrooxidans genes coding for a cytoplasmic CopZ-like copper-binding chaperone and the periplasmic copper-binding proteins rusticyanin and AcoP, which form part of an iron-oxidizing supercomplex, was found to increase when the microorganism was grown in the presence of copper. All of these proteins conferred more resistance to copper when expressed heterologously in a copper-sensitive Escherichia coli strain. This effect was absent when site-directed-mutation mutants of these proteins with altered copper-binding sites were used in this metal sensitivity assay. These results strongly suggest that the three copper-binding proteins analyzed here are copper resistance determinants in this extremophile and contribute to the high-level metal resistance of this industrially important biomining bacterium. PMID:26637599

SOLVING A COPPER CORROSION PROBLEM WITH ORTHOPHOSPHATE: INDIAN HILL, OHIO CASE STUDY

EPA Science Inventory

Many small and medium-sized water systems have troublt complying with the copper Action Level (of the Lead and Copper Rule), sometimes concurrently with meeting the lead Action level. The problem is especially troubling and widespread with ground water supplies having high alkali...

Stress- and sequence-dependent release into the culture medium of HIV-1 Nef produced in Saccharomyces cerevisiae.

PubMed

Macreadie, I G; Castelli, L A; Lucantoni, A; Azad, A A

1995-09-11

We have produced human immunodeficiency virus type 1 (HIV-1) Nef (a myristylated 206-amino-acid protein) in Saccharomyces cerevisaie and shown that, while Nef is normally found as a predominantly intracellular protein, amounts up to 40 micrograms/ml of Nef are also released into the extracellular medium during stress. By electrophoretic (SDS-PAGE) analysis the extracellular Nef is indistinguishable from intracellular Nef. Conditions of stress that lead to the release of Nef include elevated levels of copper or magnesium ions or growth at elevated temperatures. This release appears to be dependent upon the N-terminal sequences of Nef, including the presence of a myristylation site. Our observations concerning Nef release in yeast suggest new ways in which the behaviour of Nef should be examined in order to gain further insights into the development of AIDS. If the release of Nef is important in the development of AIDS, our work reveals that Nef-associated symptoms may be reduced or delayed by reducing stresses, such as fevers.

Too much is bad--an appraisal of phytotoxicity of elevated plant-beneficial heavy metal ions.

PubMed

Anjum, Naser A; Singh, Harminder P; Khan, M Iqbal R; Masood, Asim; Per, Tasir S; Negi, Asha; Batish, Daizy R; Khan, Nafees A; Duarte, Armando C; Pereira, Eduarda; Ahmad, Iqbal

2015-03-01

Heavy metal ions such as cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), and zinc (Zn) are considered essential/beneficial for optimal plant growth, development, and productivity. However, these ions readily impact functions of many enzymes and proteins, halt metabolism, and exhibit phytotoxicity at supra-optimum supply. Nevertheless, the concentrations of these heavy metal ions are increasing in agricultural soils worldwide via both natural and anthropogenic sources that need immediate attention. Considering recent breakthroughs on Co, Cu, Fe, Mn, Mo, Ni, and Zn in soil-plant system, the present paper: (a) overviews the status in soils and their uptake, transport, and significance in plants; (b) critically discusses their elevated level-mediated toxicity to both plant growth/development and cell/genome; (c) briefly cross talks on the significance of potential interactions between previous plant-beneficial heavy metal ions in plants; and (d) highlights so far unexplored aspects in the current context.

Impaired zinc and copper status in children with burn injuries: need to reassess nutritional requirements.

PubMed

Voruganti, V Saroja; Klein, Gordon L; Lu, Hong-Xing; Thomas, Suchmor; Freeland-Graves, Jeanne H; Herndon, David N

2005-09-01

Major burns are associated with impaired Zn and Cu status. These micronutrients are essential for bone matrix formation, linear growth, and wound healing. This study evaluated the status of Zn and Cu in burned children and assessed adequacy of supplementation. Six children, mean total body surface area (TBSA), 54+/-9% (S.D.), were recruited. Nutrient intakes, plasma, wound exudate, and 24h urine samples were collected and analyzed for Zn and Cu. Bone mineral content was assessed by dual energy X-ray absorptiometry. Dietary Zn and Cu were three times the dietary reference, and mean plasma concentrations of Zn and Cu were low at admission and discharge. Urinary Zn was elevated at admission, whereas Cu was elevated at both times. Wound Zn and Cu concentrations exceeded plasma concentrations, suggesting that inflammatory wound exudate was a primary route of loss. We demonstrate that burn injury in children results in low plasma levels of Zn and Cu that are inadequately compensated during hospitalization.

The effect of copper deficiency on fetal growth and liver anti-oxidant capacity in the Cohen diabetic rat model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ergaz, Zivanit, E-mail: zivanit@hadassah.org.il; Shoshani-Dror, Dana; Guillemin, Claire

High sucrose low copper diet induces fetal growth restriction in the three strains of the Cohen diabetic rats: an inbred copper deficient resistant (CDr), an inbred copper deficient sensitive (CDs that become diabetic on high sucrose low copper diet -HSD) and an outbred Wistar derived Sabra rats. Although those growth restricted fetuses also exhibit increased oxidative stress, antioxidants do not restore normal growth. In the present study, we evaluated the role of copper deficiency in the HSD induced fetal growth restriction by adding to the drinking water of the rats 1 ppm or 2 ppm of copper throughout their pregnancy.more » Fetal and placental growth in correlation with fetal liver copper content and anti-oxidant capacity was evaluated on day 21 of pregnancy. HSD compared to regular chow induced fetal growth restriction, which was most significant in the Cohen diabetic sensitive animals. The addition of 1 ppm and 2 ppm copper to the drinking water normalized fetal growth in a dose dependent manner and reduced the degree of hyperglycemia in the diabetes sensitive rats. The CDs fetuses responded to the HSD with lower catalase like activity, and less reduced superoxide dismutase levels compared to the Sabra strain, and had high malondialdehyde levels even when fed regular chow. Immunostaining was higher for nitrotyrosine among the CDr and higher for hypoxia factor 1 α among the CDs. We conclude that in our model of dietary-induced fetal growth restriction, copper deficiency plays a major etiologic role in the decrease of fetal growth and anti-oxidant capacity. -- Highlights: ► High sucrose low copper diet restricted fetal growth in the Cohen diabetic rat model ► Maternal copper blood levels directly correlated with fetal liver copper content ► Copper supplementation decreased embryonic resorption in the inbred strains ► Copper supplementation reduced hyperglycemia in the sucrose sensitive inbred strain ► Copper supplementation alleviated growth restriction and oxidative stress of liver.« less

Gastrointestinal effects associated with soluble and insoluble copper in drinking water.

PubMed Central

Pizarro, F; Olivares, M; Araya, M; Gidi, V; Uauy, R

2001-01-01

The aim of this study was to determine whether total copper or soluble copper concentration is associated with gastrointestinal signs and symptoms. Forty-five healthy adult women (18-55 years of age), living in Santiago, Chile, ingested tap water with 5 mg/L of copper containing different ratios of soluble copper (copper sulfate) and insoluble copper (copper oxide) over a 9-week period. Three randomized sequences of the different copper ratios (0:5, 1:4, 2:3, 3:2, and 5:0 mg/L) were followed. Subjects recorded their water consumption and gastrointestinal symptoms daily on a special form. Mean water consumption was similar among groups. Serum copper levels, ceruloplasmin, and activities of liver enzymes were within normal limits. No differences were detected between the means of biochemical parameters at the beginning and at the end of the study. Twenty subjects presented gastrointestinal disturbances at least once during the study, 9 suffered diarrhea (with or without abdominal pain and vomiting), and the other 11 subjects reported abdominal pain, nausea, or vomiting. No differences were found in incidence of abdominal pain, nausea, vomiting, and diarrhea regardless of the ratio of copper sulfate to copper oxide. In conclusion, both copper sulfate (a soluble compound) and copper oxide (an insoluble compound) have comparable effects on the induction of gastrointestinal manifestations, implying that similar levels of ionic copper were present in the stomach. PMID:11673125

The Intestinal Copper Exporter CUA-1 Is Required for Systemic Copper Homeostasis in Caenorhabditis elegans.

PubMed

Chun, Haarin; Sharma, Anuj Kumar; Lee, Jaekwon; Chan, Jefferson; Jia, Shang; Kim, Byung-Eun

2017-01-06

Copper plays key catalytic and regulatory roles in biochemical processes essential for normal growth, development, and health. Defects in copper metabolism cause Menkes and Wilson's disease, myeloneuropathy, and cardiovascular disease and are associated with other pathophysiological states. Consequently, it is critical to understand the mechanisms by which organisms control the acquisition, distribution, and utilization of copper. The intestinal enterocyte is a key regulatory point for copper absorption into the body; however, the mechanisms by which intestinal cells transport copper to maintain organismal copper homeostasis are poorly understood. Here, we identify a mechanism by which organismal copper homeostasis is maintained by intestinal copper exporter trafficking that is coordinated with extraintestinal copper levels in Caenorhabditis elegans Specifically, we show that CUA-1, the C. elegans homolog of ATP7A/B, localizes to lysosome-like organelles (gut granules) in the intestine under copper overload conditions for copper detoxification, whereas copper deficiency results in a redistribution of CUA-1 to basolateral membranes for copper efflux to peripheral tissues. Worms defective in gut granule biogenesis exhibit defects in copper sequestration and increased susceptibility to toxic copper levels. Interestingly, however, a splice isoform CUA-1.2 that lacks a portion of the N-terminal domain is targeted constitutively to the basolateral membrane irrespective of dietary copper concentration. Our studies establish that CUA-1 is a key intestinal copper exporter and that its trafficking is regulated to maintain systemic copper homeostasis. C. elegans could therefore be exploited as a whole-animal model system to study regulation of intra- and intercellular copper trafficking pathways. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Serum levels of zinc and copper in epileptic children during long-term therapy with anticonvulsants.

PubMed

Talat, Mohamed A; Ahmed, Anwar; Mohammed, Lamia

2015-10-01

To evaluate the serum levels of zinc and copper in epileptic children during the long-term treatment of anticonvulsant drugs and correlate this with healthy subjects. A hospital-based group matched case-control study was conducted in the Department of Pediatrics, Faculty of Medicine, Zagazig University, Zagazig, Egypt between November 2013 and October 2014. Ninety patients aged 7.1 ± 3.6 years were diagnosed with epilepsy by a neurologist. The control group was selected from healthy individuals and matched to the case group. Serum zinc and copper were measured by the calorimetric method using a colorimetric method kit. The mean zinc level was 60.1 ± 22.6 ug/dl in the cases, and 102.1 ± 18 ug/dl in the controls (p<0.001). The mean copper level was 180.1 ± 32.4 ug/dl in cases compared with 114.5 ± 18.5 ug/dl in controls (p<0.001). Serum zinc levels in epileptic children under drug treatment are lower compared with healthy children. Also, serum copper levels in these patients are significantly higher than in healthy people. No significant difference in the levels of serum copper and zinc was observed in using one drug or multiple drugs in the treatment of epileptic patients.

Serum levels of zinc and copper in epileptic children during long-term therapy with anticonvulsants

PubMed Central

Talat, Mohamed A.; Ahmed, Anwar; Mohammed, Lamia

2015-01-01

Objective: To evaluate the serum levels of zinc and copper in epileptic children during the long-term treatment of anticonvulsant drugs and correlate this with healthy subjects. Methods: A hospital-based group matched case-control study was conducted in the Department of Pediatrics, Faculty of Medicine, Zagazig University, Zagazig, Egypt between November 2013 and October 2014. Ninety patients aged 7.1±3.6 years were diagnosed with epilepsy by a neurologist. The control group was selected from healthy individuals and matched to the case group. Serum zinc and copper were measured by the calorimetric method using a colorimetric method kit. Results: The mean zinc level was 60.1±22.6 ug/dl in the cases, and 102.1±18 ug/dl in the controls (p<0.001). The mean copper level was 180.1±32.4 ug/dl in cases compared with 114.5±18.5 ug/dl in controls (p<0.001). Conclusion: Serum zinc levels in epileptic children under drug treatment are lower compared with healthy children. Also, serum copper levels in these patients are significantly higher than in healthy people. No significant difference in the levels of serum copper and zinc was observed in using one drug or multiple drugs in the treatment of epileptic patients. PMID:26492112

Copper-granule-catalyzed microwave-assisted click synthesis of polyphenol dendrimers.

PubMed

Lee, Choon Young; Held, Rich; Sharma, Ajit; Baral, Rom; Nanah, Cyprien; Dumas, Dan; Jenkins, Shannon; Upadhaya, Samik; Du, Wenjun

2013-11-15

Syringaldehyde- and vanillin-based antioxidant dendrimers were synthesized via microwave-assisted alkyne-azide 1,3-dipolar cycloaddition using copper granules as a catalyst. The use of Cu(I) as a catalyst resulted in copper contaminated dendrimers. To produce copper-free antioxidant dendrimers for biological applications, Cu(I) was substituted with copper granules. Copper granules were ineffective at both room temperature and under reflux conditions (<5% yield). However, they were an excellent catalyst when dendrimer synthesis was performed under microwave irradiation, giving yields up to 94% within 8 h. ICP-mass analysis of the antioxidant dendrimers obtained with this method showed virtually no copper contamination (9 ppm), which was the same as the background level. The synthesized antioxidants, free from copper contamination, demonstrated potent radical scavenging with IC50 values of less than 3 μM in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. In comparison, dendrimers synthesized from Cu(I)-catalyzed click chemistry showed a high level of copper contamination (4800 ppm) and no detectable antioxidant activity.

Dextran-Catechin: An anticancer chemically-modified natural compound targeting copper that attenuates neuroblastoma growth

PubMed Central

Vittorio, Orazio; Brandl, Miriam; Cirillo, Giuseppe; Kimpton, Kathleen; Hinde, Elizabeth; Gaus, Katharina; Yee, Eugene; Kumar, Naresh; Duong, Hien; Fleming, Claudia; Haber, Michelle; Norris, Murray; Boyer, Cyrille; Kavallaris, Maria

2016-01-01

Neuroblastoma is frequently diagnosed at advanced stage disease and treatment includes high dose chemotherapy and surgery. Despite the use of aggressive therapy survival rates are poor and children that survive their disease experience long term side effects from their treatment, highlighting the need for effective and less toxic therapies. Catechin is a natural polyphenol with anti-cancer properties and limited side effects, however its mechanism of action is unknown. Here we report that Dextran-Catechin, a conjugated form of catechin that increases serum stability, is preferentially and markedly active against neuroblastoma cells having high levels of intracellular copper, without affecting non-malignant cells. Copper transporter 1 (CTR1) is the main transporter of copper in mammalian cells and it is upregulated in neuroblastoma. Functional studies showed that depletion of CTR1 expression reduced intracellular copper levels and led to a decrease in neuroblastoma cell sensitivity to Dextran-Catechin, implicating copper in the activity of this compound. Mechanistically, Dextran-Catechin was found to react with copper, inducing oxidative stress and decreasing glutathione levels, an intracellular antioxidant and regulator of copper homeostasis. In vivo, Dextran-Catechin significantly attenuated tumour growth in human xenograft and syngeneic models of neuroblastoma. Thus, Dextran-Catechin targets copper, inhibits tumour growth, and may be valuable in the treatment of aggressive neuroblastoma and other cancers dependent on copper for their growth. PMID:27374085

Copper/zinc and copper/selenium ratios, and oxidative stress as biochemical markers in recurrent aphthous stomatitis.

PubMed

Ozturk, Perihan; Belge Kurutas, Ergul; Ataseven, Arzu

2013-10-01

Recurrent aphthous stomatitis (RAS) is a common oral mucosal disorder characterized by recurrent, painful oral aphthae, and oxidative stress presumably contributes to its pathogenesis. The aim of this study is to scrutinize the relationship between oxidative stress and serum trace elements (copper, Cu; zinc, Zn; selenium, Se), and to evaluate the ratios of Cu/Zn and Cu/Se in this disorder. Patients with RAS (n = 33) and age- and sex-matched healthy control subjects (n = 30) were enrolled in this study. Malondialdehyde (MDA) concentrations in plasma and the activities of superoxide dismutase (SOD1; CuZnSOD), glutathione peroxidase (GPx) and catalase (CAT) in erythrocyte were determined as spectrophotometric. Also, the levels of Se, Zn and Cu in serum were determined on flame and furnace atomic absorption spectrophotometer using Zeeman background correction. Oxidative stress was confirmed by the significant elevation in plasma MDA, and by the significant decrease in CAT, SOD1, and GPx (p < 0.05). When compared to controls, Zn and Se levels were significantly lower in patients, whereas Cu levels was higher in RAS patients than those in controls (p < 0.05). In addition, the correlation results of this study were firstly shown that there were significant and positive correlations between Se-CAT, Se-GPx, and Cu-MDA parameters, but negative correlations between Se-Cu, Se-MDA, Cu-CAT, Cu-SOD1 and Cu-GPx parameters in RAS patients. Furthermore, the ratios of Cu/Zn and Cu/Se were significantly higher in the patients than the control subjects (p < 0.05). Our results indicated that lipid peroxidation associated with the imbalance of the trace elements seems to play a crucial role in the pathogenesis of RAS. Furthermore, the serum Cu/Zn and Cu/Se ratios may be used as biochemical markers in these patients. Crown Copyright © 2013. Published by Elsevier GmbH. All rights reserved.

CsoR Is Essential for Maintaining Copper Homeostasis in Mycobacterium tuberculosis

PubMed Central

Marcus, Sarah A.; Sidiropoulos, Sarah W.; Steinberg, Howard; Talaat, Adel M.

2016-01-01

Mycobacterium tuberculosis, a pathogen infecting one third of the world population, faces numerous challenges within the host, including high levels of copper. We have previously shown that M. tuberculosis CsoR is a copper inducible transcriptional regulator. Here we examined the hypothesis that csoR is necessary for maintaining copper homeostasis and surviving under various stress conditions. With an unmarked csoR knockout strain, we were able to characterize the role of csoR in M. tuberculosis as it faced copper and host stress. Growth under high levels of copper demonstrated that M. tuberculosis survives copper stress significantly better in the absence of csoR. Yet under minimal levels of copper, differential expression analysis revealed that the loss of csoR results in a cell wide hypoxia-type stress response with the induction of the DosR regulon. Despite the stress placed on M. tuberculosis by the loss of csoR, survival of the knockout strain was increased compared to wild type during the early chronic stages of mouse infection, suggesting that csoR could play an active role in modulating M. tuberculosis fitness within the host. Overall, analysis of CsoR provided an increased understanding of the M. tuberculosis copper response with implications for other intracellular pathogens harboring CsoR. PMID:26999439

Demystifying Controlling Copper Corrosion

EPA Science Inventory

The LCR systematically misses the highest health and corrosion risk sites for copper. Additionally, there are growing concerns for WWTP copper in sludges and discharge levels. There are many corrosion control differences between copper and lead. This talk explains the sometimes c...

EVALUATING THE IMPACT OF WATER CHEMISTRY ON CUPROSOLVENCY AND COPPER CORROSION BY-PRODUCT USING A SIMPLE COPPER PIPE RECIRCULATING LOOP SYSTEM

EPA Science Inventory

1991, EPA publicized the Lead and Copper Rule (LCR),which set regulations to minimize the amount of lead copper in drinking water. The LCR set the copper action level at 1.3 mg/L in more then 10% of customer’s first-draw taps sampled. Potential health effects of copper include vo...

Selenium, copper, zinc, iron levels and mortality in patients with sepsis and systemic inflammatory response syndrome in Western Black Sea Region, Turkey.

PubMed

Ayoglu, Hilal; Sezer, Ustun; Akin, Mehmet; Okyay, Dilek; Ayoglu, Ferruh; Can, Murat; Kucukosman, Gamze; Piskin, Ozcan; Aydin, Bengu; Cimencan, Murat; Gur, Abdullah; Turan, Isil

2016-04-01

To evaluate the changing levels of selenium, copper, zinc and iron in patients with sepsis and systemic inflammatory response syndrome and their influence on mortality. The prospective study was conducted at a tertiary care university hospital in Zonguldak city in the western Black Sea region of Turkey from January 2012 to December 2013, and comprised patients with sepsis and systemic inflammatory response syndrome. Blood samples were taken on 1st, 3rd, 5th and 7th days to measure serum selenium, copper, zinc and iron levels. Patients' demographic data, presence of additional diseases and mortality were recorded. Of the 57 patients, 28(49.1%) were female and 29(50.9%) were male, with an overall mean age of 60.3±19.4 years, mean height of 166.1±11.4cm, mean weight of 76.5±17.5kg. Copper and zinc levels were in the normal range, while selenium and iron levels were lower than the limit values at all measuring periods. There was no significant difference between first and other days in accordance with element levels (p>0.05). Baseline copper levels in patients with malignancy were lower than patients without malignancy (p< 0.05). In hypertensive patients, baseline copper levels were higher and 7th day levels were lower than non-hypertensive (p< 0.05). Baseline selenium levels of those who died were lower than the other patients (p< 0.05). Selenium and iron levels were decreased in patients with sepsis-systemic inflammatory response syndrome and copper levels were lower in patients with malignancy, hypertension and chronic obstructive pulmonary disease (p< 0.05). There was no change in zinc levels of the patients. Reduced basal selenium levels of patients with sepsis and systemic inflammatory response syndrome were associated with mortality.

The cardiac copper chaperone proteins Sco1 and CCS are up-regulated, but Cox 1 and Cox4 are down-regulated, by copper deficiency.

PubMed

Getz, Jean; Lin, Dingbo; Medeiros, Denis M

2011-10-01

Copper is ferried in a cell complexed to chaperone proteins, and in the heart much copper is required for cytochrome c oxidase (Cox). It is not completely understood how copper status affects the levels of these proteins. Here we determined if dietary copper deficiency could up- or down-regulate select copper chaperone proteins and Cox subunits 1 and 4 in cardiac tissue of rats. Sixteen weanling male Long-Evans rats were randomized into treatment groups, one group receiving a copper-deficient diet (<1 mg Cu/kg diet) and one group receiving a diet containing adequate copper (6 mg Cu/kg diet) for 5 weeks. Hearts were removed, weighed, and non-myofibrillar proteins separated to analyze for levels of CCS, Sco1, Ctr1, Cox17, Cox1, and Cox4 by SDS-PAGE and Western blotting. No changes were observed in the concentrations of CTR1 and Cox17 between copper-adequate and copper-deficient rats. CCS and Sco1 were up-regulated and Cox1 and Cox4 were both down-regulated as a result of copper deficiency. These data suggest that select chaperone proteins and may be up-regulated, and Cox1 and 4 down-regulated, by a dietary copper deficiency, whereas others appear not to be affected by copper status.

Widespread arsenic contamination of soils in residential areas and public spaces: an emerging regulatory or medical crisis?

PubMed

Belluck, D A; Benjamin, S L; Baveye, P; Sampson, J; Johnson, B

2003-01-01

A critical review finds government agencies allow, permit, license, or ignore arsenic releases to surface soils. Release rates are controlled or evaluated using risk-based soil contaminant numerical limits employing standardized risk algorithms, chemical-specific and default input values. United States arsenic residential soil limits, approximately 0.4- approximately 40 ppm, generally correspond to a one-in-one-million to a one-in-ten-thousand incremental cancer risk range via ingestion of or direct contact with contaminated residential soils. Background arsenic surface soil levels often exceed applicable limits. Arsenic releases to surface soils (via, e.g., air emissions, waste recycling, soil amendments, direct pesticide application, and chromated copper arsenic (CCA)-treated wood) can result in greatly elevated arsenic levels, sometimes one to two orders of magnitude greater than applicable numerical limits. CCA-treated wood, a heavily used infrastructure material at residences and public spaces, can release sufficient arsenic to result in surface soil concentrations that exceed numerical limits by one or two orders of magnitude. Although significant exceedence of arsenic surface soil numerical limits would normally result in regulatory actions at industrial or hazardous waste sites, no such pattern is seen at residential and public spaces. Given the current risk assessment paradigm, measured or expected elevated surface soil arsenic levels at residential and public spaces suggest that a regulatory health crisis of sizeable magnitude is imminent. In contrast, available literature and a survey of government agencies conducted for this paper finds no verified cases of human morbidity or mortality resulting from exposure to elevated levels of arsenic in surface soils. This concomitance of an emerging regulatory health crisis in the absence of a medical crisis is arguably partly attributable to inadequate government and private party attention to the issue.

Species-Specific Responses of Juvenile Rockfish to Elevated pCO2: From Behavior to Genomics

PubMed Central

Hamilton, Scott L.; Logan, Cheryl A.; Fennie, Hamilton W.; Sogard, Susan M.; Barry, James P.; Makukhov, April D.; Tobosa, Lauren R.; Boyer, Kirsten; Lovera, Christopher F.; Bernardi, Giacomo

2017-01-01

In the California Current ecosystem, global climate change is predicted to trigger large-scale changes in ocean chemistry within this century. Ocean acidification—which occurs when increased levels of atmospheric CO2 dissolve into the ocean—is one of the biggest potential threats to marine life. In a coastal upwelling system, we compared the effects of chronic exposure to low pH (elevated pCO2) at four treatment levels (i.e., pCO2 = ambient [500], moderate [750], high [1900], and extreme [2800 μatm]) on behavior, physiology, and patterns of gene expression in white muscle tissue of juvenile rockfish (genus Sebastes), integrating responses from the transcriptome to the whole organism level. Experiments were conducted simultaneously on two closely related species that both inhabit kelp forests, yet differ in early life history traits, to compare high-CO2 tolerance among species. Our findings indicate that these congeners express different sensitivities to elevated CO2 levels. Copper rockfish (S. caurinus) exhibited changes in behavioral lateralization, reduced critical swimming speed, depressed aerobic scope, changes in metabolic enzyme activity, and increases in the expression of transcription factors and regulatory genes at high pCO2 exposure. Blue rockfish (S. mystinus), in contrast, showed no significant changes in behavior, swimming physiology, or aerobic capacity, but did exhibit significant changes in the expression of muscle structural genes as a function of pCO2, indicating acclimatization potential. The capacity of long-lived, late to mature, commercially important fish to acclimatize and adapt to changing ocean chemistry over the next 50–100 years is likely dependent on species-specific physiological tolerances. PMID:28056071

Subneurotoxic copper(II)-induced NF-κB-dependent microglial activation is associated with mitochondrial ROS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Zhuqin; Yu, Fengxiang; Gong, Ping

2014-04-15

Microglia-mediated neuroinflammation and the associated neuronal damage play critical roles in the pathogenesis of neurodegenerative disorders. Evidence shows an elevated concentration of extracellular copper(II) in the brains of these disorders, which may contribute to neuronal death through direct neurotoxicity. Here we explored whether extracellular copper(II) triggers microglial activation. Primary rat microglia and murine microglial cell line BV-2 cells were cultured and treated with copper(II). The content of tumor necrosis factor-α (TNF-α) and nitric oxide in the medium was determined. Extracellular hydrogen peroxide was quantified by a fluorometric assay with Amplex Red. Mitochondrial superoxide was measured by MitoSOX oxidation. At subneurotoxicmore » concentrations, copper(II) treatment induced a dose- and time-dependent release of TNF-α and nitric oxide from microglial cells, and caused an indirect, microglia-mediated neurotoxicity that was blocked by inhibition of TNF-α and nitric oxide production. Copper(II)-initiated microglial activation was accompanied with reduced IkB-α expression as well as phosphorylation and translocation of nuclear factor-κB (NF-κB) p65 and was blocked by NF-κB inhibitors (BAY11-7082 and SC-514). Moreover, copper(II) treatment evoked a rapid release of hydrogen peroxide from microglial cells, an effect that was not affected by NADPH oxidase inhibitors. N-acetyl-cysteine, a scavenger of reactive oxygen species (ROS), abrogated copper(II)-elicited microglial release of TNF-α and nitric oxide and subsequent neurotoxicity. Importantly, mitochondrial production of superoxide, paralleled to extracellular release of hydrogen peroxide, was induced after copper(II) stimulation. Our findings suggest that extracellular copper(II) at subneurotoxic concentrations could trigger NF-κB-dependent microglial activation and subsequent neurotoxicity. NADPH oxidase-independent, mitochondria-derived ROS may be involved in this activation. - Highlights: • Subneurotoxic copper(II) triggers NF-κB-dependent microglial activation. • This activation leads to hippocampal neuronal death. • This activation may involve mitochondria-derived reactive oxygen species.« less

An elevated level of copper zinc superoxide dismutase fails to prevent oxygen induced retinopathy in mice.

PubMed

Klaeger, C; de Sa, L; Klaeger, A J; Carlson, E J; Good, W V; Epstein, C J

1996-05-01

To determine whether a higher level of copper zinc superoxide dismutase (CuZnSOD) can reduce the severity of oxygen induced retinopathy (OIR) in a mouse model. CuZnSOD transgenic mice with a threefold increase in CuZnSOD activity and control non-transgenic mice were exposed to 90% oxygen for 12 hours a day during the first 5 days of life. After oxygen treatment, all mice were reared in room air for 10 days. Another group of transgenic and non-transgenic mice were kept in room air for 15 days and served as control groups for the oxygen effect. At day 15, all mice were killed and perfused with India ink. The retinas were flat mounted on slides and examined with a light microscope. There was a statistically significant increase in the incidence of OIR in mice exposed to high levels of oxygen, whether or not they were transgenic. However, there was no statistically significant difference in the severity of OIR between oxygen treated transgenic and non-transgenic mice. A threefold higher CuZnSOD activity does not protect against OIR in mice. This is an unexpected finding, since oxygen radicals are considered a major factor causing OIR, and increased CuZnSOD activity has reduced oxygen radical induced damage in several neuronal and non-neuronal systems. The possibility of a damaging role for other radicals not affected by CuZnSOD cannot be excluded.

Low levels of copper reduce the reproductive success of a mobile invertebrate predator.

PubMed

Lee, Ka-Man; Johnston, Emma L

2007-09-01

Marine organisms that occur in urbanised bays can be exposed to low-level chronic pollution that results in sublethal changes to behavior or reproduction. The effects of low levels of copper on the reproductive success of a mobile invertebrate were assessed. Free living flatworms are common predators of bivalves and barnacles. Flatworms (Stylochus pygmaeus) were exposed to low levels of copper ranging from 0 to 25 microg L(-1) in the presence and absence of their barnacle prey (Balanus variegatus). Flatworms laid fewer egg batches when exposed to copper and the hatching success of the eggs was also reduced. Exposure to 25 microg L(-1) copper for 10 d reduced the reproductive success of flatworms by up to 80%. Results were consistent regardless of the presence or absence of prey (barnacles). Barnacles were only moderately affected by copper but exhibited major avoidance behavior (feeding inhibition) in the presence of flatworm predators. This is the first ecotoxicological study on marine flatworms. Experiments are required to quantify the effects of flatworm predator populations on sessile invertebrate community structure in the field.

Cytoplasmic CopZ-Like Protein and Periplasmic Rusticyanin and AcoP Proteins as Possible Copper Resistance Determinants in Acidithiobacillus ferrooxidans ATCC 23270.

PubMed

Navarro, Claudio A; von Bernath, Diego; Martínez-Bussenius, Cristóbal; Castillo, Rodrigo A; Jerez, Carlos A

2016-02-15

Acidophilic organisms, such as Acidithiobacillus ferrooxidans, possess high-level resistance to copper and other metals. A. ferrooxidans contains canonical copper resistance determinants present in other bacteria, such as CopA ATPases and RND efflux pumps, but these components do not entirely explain its high metal tolerance. The aim of this study was to find other possible copper resistance determinants in this bacterium. Transcriptional expression of A. ferrooxidans genes coding for a cytoplasmic CopZ-like copper-binding chaperone and the periplasmic copper-binding proteins rusticyanin and AcoP, which form part of an iron-oxidizing supercomplex, was found to increase when the microorganism was grown in the presence of copper. All of these proteins conferred more resistance to copper when expressed heterologously in a copper-sensitive Escherichia coli strain. This effect was absent when site-directed-mutation mutants of these proteins with altered copper-binding sites were used in this metal sensitivity assay. These results strongly suggest that the three copper-binding proteins analyzed here are copper resistance determinants in this extremophile and contribute to the high-level metal resistance of this industrially important biomining bacterium. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

The influence of regional geological settings on the seismic hazard level in copper mines in the Legnica-Głogów Copper Belt Area (Poland)

NASA Astrophysics Data System (ADS)

Burtan, Zbigniew

2017-11-01

The current level of rockburst hazard in copper mines of the (LGOM) Legnica- Głogów Copper Belt Area is mostly the consequence of mining-induced seismicity, whilst the majority of rockbursting events registered to date were caused by high-energy tremors. The analysis of seismic readings in recent years reveals that the highest seismic activity among the copper mines in the LGOM is registered in the mine Rudna. This study investigates the seismic activity in the rock strata in the Rudna mine fields over the years 2006-2015. Of particular interest are the key seismicity parameters: the number of registered seismic events, the total energy emissions, the energy index. It appears that varied seismic activity in the area may be the function of several variables: effective mining thickness, the thickness of burst-prone strata and tectonic intensity. The results support and corroborate the view that principal factors influencing the actual seismic hazard level are regional geological conditions in the copper mines within the Legnica-Głogów Copper Belt Area.

Catalysts for coal liquefaction processes

DOEpatents

Garg, Diwakar

1986-01-01

Improved catalysts for catalytic solvent refining or hydroliquefaction of non-anthracitic coal at elevated temperatures under hydrogen pressure in a hydrogen donor solvent comprise a combination of zinc or copper, or a compound thereof, and a Group VI or non-ferrous Group VIII metal, or a compound thereof.

Catalysts for coal liquefaction processes

DOEpatents

Garg, D.

1986-10-14

Improved catalysts for catalytic solvent refining or hydroliquefaction of non-anthracitic coal at elevated temperatures under hydrogen pressure in a hydrogen donor solvent comprise a combination of zinc or copper, or a compound thereof, and a Group VI or non-ferrous Group VIII metal, or a compound thereof.

Thrust chamber material technology program

NASA Technical Reports Server (NTRS)

Andrus, J. S.; Bordeau, R. G.

1989-01-01

This report covers work performed at Pratt & Whitney on development of copper-based materials for long-life, reusable, regeneratively cooled rocket engine thrust chambers. The program approached the goal of enhanced cyclic life through the application of rapid solidification to alloy development, to introduce fine dispersions to strengthen and stabilize the alloys at elevated temperatures. After screening of alloy systems, copper-based alloys containing Cr, Co, Hf, Ag, Ti, and Zr were processed by rapid-solidification atomization in bulk quantities. Those bulk alloys showing the most promise were characterized by tensile testing, thermal conductivity testing, and elevated-temperature, low-cycle fatigue (LFC) testing. Characterization indicated that Cu- 1.1 percent Hf exhibited the greatest potential as an improved-life thrust chamber material, exhibiting LCF life about four times that of NASA-Z. Other alloys (Cu- 0.6 percent Zr, and Cu- 0.6 percent Zr- 1.0 percent Cr) exhibited promise for use in this application, but needed more development work to balance properties.

Is copper chelation an effective anti-angiogenic strategy for cancer treatment?

PubMed

Antoniades, V; Sioga, A; Dietrich, E M; Meditskou, S; Ekonomou, L; Antoniades, K

2013-12-01

Angiogenesis and the acquisition of an angiogenic phenotype is important for cancer cell proliferation. Copper in an essential trace element that participates in many enzymatic complexes like the cytochrome c, superoxide dismutase and lysyl oxidase and it is involved in processes, like embryogenesis, growth, angiogenesis and carcinogenesis. In particular, its involvement in carcinogenesis was described for the first time in oral submucous fibrosis, where fibroblasts produce large amounts of collagen in the presence of copper. Copper's action in carcinogenesis is two-fold: (1) it participates in reactions with an increased redox potential that result in the production of oxidative products and oxidative stress. Through this mechanism, copper may cause DNA mutations in the nucleus and mitochondria or alterations to membrane phospholipids, (2) it participates in angiogenesis even in the absence of angiogenic molecules, as it was reported for the first time in rabbit cornea models with copolymer pellets charged with PGE1. Copper chelation regimens like penicillamine and tetrathiomolybdate are being described in the literature as having anti-angiogenic, anti-fibrotic and anti-inflammatory actions. Animal models of brain cancer that evaluated the anti-angiogenic properties of copper, have proven evidence of the reduction of tumor's microvascular supply, tumor volume and vascular permeability after plasma copper levels reduction. Interestingly, plasma copper levels reduction was shown to suppress micrometastases generation in mice models of breast cancer. We hypothesize that copper chelation therapy: increases oxidative stress in cancer cells to a level that does not allow survival because of the reduction of anti-oxidative enzymes production. It may also result in inhibition of angiogenesis and of the initiation of the angiogenic switch, because copper normally enhances endothelial cell migration and proliferation, improves binding of growth factors to endothelial cells and enhances the expression of angiogenic molecules. Copper chelation may also reduce extracellular matrix degradation and cancer spread, through reduction of MMP-9 production and probably of other collagenases and may inhibit propagation of micrometastases. However, copper chelation therapy may enhance angiogenesis through reduction of thrombospondin-1, that results into an increase in VEGF-VEGFR2 complexes and a high level of active MMP-9. These hypotheses help in understanding of the anti-angiogenic action of copper chelation therapies and of the complex network of interactions between copper and other molecules involved in angiogenesis. It may also stimulate further research regarding differences in copper metabolism, the effects of anti-copper regimens on organs, the development of resistance, and their possible angiogenic action through thrombospondin expression reduction. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of dietary supplementation with vitamin C and vitamin E and their combination on growth performance, some biochemical parameters, and oxidative stress induced by copper toxicity in broilers.

PubMed

Cinar, Miyase; Yildirim, Ebru; Yigit, A Arzu; Yalcinkaya, Ilkay; Duru, Ozkan; Kisa, Uçler; Atmaca, Nurgul

2014-05-01

This study investigated effects of dietary supplementation with vitamin C, vitamin E on performance, biochemical parameters, and oxidative stress induced by copper toxicity in broilers. A total of 240, 1-day-old, broilers were assigned to eight groups with three replicates of 10 chicks each. The groups were fed on the following diets: control (basal diet), vitamin C (250 mg/kg diet), vitamin E (250 mg/kg diet), vitamin C + vitamin E (250 mg/kg + 250 mg/kg diet), and copper (300 mg/kg diet) alone or in combination with the corresponding vitamins. At the 6th week, the body weights of broilers were decreased in copper, copper + vitamin E, and copper + vitamin C + vitamin E groups compared to control. The feed conversion ratio was poor in copper group. Plasma aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase activities, iron, copper concentrations, and erythrocyte malondialdehyde were increased; plasma vitamin A and C concentrations and erythrocyte superoxide dismutase were decreased in copper group compared to control. Glutathione peroxidase, vitamin C, and iron levels were increased; aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and copper levels were decreased in copper + vitamin C group, while superoxide dismutase, glutathione peroxidase, and vitamin E concentrations were increased; aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase were decreased in copper with vitamin E group compared to copper group. The vitamin C concentrations were increased; copper, uric acid, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and malondialdehyde were decreased in copper + vitamin C + vitamin E group compared to copper group. To conclude, copper caused oxidative stress in broilers. The combination of vitamin C and vitamin E addition might alleviate the harmful effects of copper as demonstrated by decreased lipid peroxidation and hepatic enzymes.

Aberrant expression of copper associated genes after copper accumulation in COMMD1-deficient dogs.

PubMed

Favier, Robert P; Spee, Bart; Fieten, Hille; van den Ingh, Ted S G A M; Schotanus, Baukje A; Brinkhof, Bas; Rothuizen, Jan; Penning, Louis C

2015-01-01

COMMD1-deficient dogs progressively develop copper-induced chronic hepatitis. Since high copper leads to oxidative damage, we measured copper metabolism and oxidative stress related gene products during development of the disease. Five COMMD1-deficient dogs were studied from 6 months of age over a period of five years. Every 6 months blood was analysed and liver biopsies were taken for routine histological evaluation (grading of hepatitis), rubeanic acid copper staining and quantitative copper analysis. Expression of genes involved in copper metabolism (COX17, CCS, ATOX1, MT1A, CP, ATP7A, ATP7B, ) and oxidative stress (SOD1, catalase, GPX1 ) was measured by qPCR. Due to a sudden death of two animals, the remaining three dogs were treated with d-penicillamine from 43 months of age till the end of the study. Presented data for time points 48, 54, and 60 months was descriptive only. A progressive trend from slight to marked hepatitis was observed at histology, which was clearly preceded by an increase in semi-quantitative copper levels starting at 12 months until 42 months of age. During the progression of hepatitis most gene products measured were transiently increased. Most prominent was the rapid increase in the copper binding gene product MT1A mRNA levels. This was followed by a transient increase in ATP7A and ATP7B mRNA levels. In the sequence of events, copper accumulation induced progressive hepatitis followed by a transient increase in gene products associated with intracellular copper trafficking and temporal activation of anti-oxidative stress mechanisms. Copyright © 2014 Elsevier GmbH. All rights reserved.

In utero copper treatment for Menkes disease associated with a severe ATP7A mutation

PubMed Central

Haddad, Marie Reine; Macri, Charles J.; Holmes, Courtney S.; Goldstein, David S.; Jacobson, Beryl E.; Centeno, Jose A.; Popek, Edwina J.; Gahl, Willam A.; Kaler, Stephen G.

2012-01-01

Menkes disease is a lethal X-linked recessive neurodegenerative disorder of copper transport caused by mutations in ATP7A, which encodes a copper-transporting ATPase. Early postnatal treatment with copper injections often improves clinical outcomes in affected infants. While Menkes disease newborns appear normal neurologically, analyses of fetal tissues including placenta indicate abnormal copper distribution and suggest a prenatal onset of the metal transport defect. In an affected fetus whose parents found termination unacceptable and who understood the associated risks, we began in utero copper histidine treatment at 31.5 weeks gestational age. Copper histidine (900 μg per dose) was administered directly to the fetus by intramuscular injection (fetal quadriceps or gluteus) under ultrasound guidance. Percutaneous umbilical blood sampling enabled serial measurement of fetal copper and ceruloplasmin levels that were used to guide therapy over a four-week period. Fetal copper levels rose from 17 μg/dL prior to treatment to 45 μg/dL, and ceruloplasmin levels from 39 mg/L to 122 mg/L. After pulmonary maturity was confirmed biochemically, the baby was delivered at 35.5 weeks and daily copper histidine therapy (250 μg sc b.i.d.) was begun. Despite this very early intervention with copper, the infant showed hypotonia, developmental delay, and electroencephalographic abnormalities and died of respiratory failure at 5.5 months of age. The patient’s ATP7A mutation, which severely disrupted mRNA splicing, resulted in complete absence of ATP7A protein on Western blots. These investigations suggest that prenatally initiated copper replacement is inadequate to correct Menkes disease caused by severe loss-of-function mutations, and that postnatal ATP7A gene addition represents a rational approach in such circumstances. PMID:22695177

Zn II(atsm) is protective in amyotrophic lateral sclerosis model mice via a copper delivery mechanism.

PubMed

McAllum, Erin J; Roberts, Blaine R; Hickey, James L; Dang, Theresa N; Grubman, Alexandra; Donnelly, Paul S; Liddell, Jeffrey R; White, Anthony R; Crouch, Peter J

2015-09-01

Mutations in the metalloprotein Cu,Zn-superoxide dismutase (SOD1) cause approximately 20% of familial cases of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease for which effective therapeutics do not yet exist. Transgenic rodent models based on over-expression of mutant SOD1 have been developed and these have provided opportunity to test new therapeutic strategies and to study the mechanisms of mutant SOD1 toxicity. Although the mechanisms of mutant SOD1 toxicity are yet to be fully elucidated, incorrect or incomplete metallation of SOD1 confers abnormal folding, aggregation and biochemical properties, and improving the metallation state of SOD1 provides a viable therapeutic option. The therapeutic effects of delivering copper (Cu) to mutant SOD1 have been demonstrated recently. The aim of the current study was to determine if delivery of zinc (Zn) to SOD1 was also therapeutic. To investigate this, SOD1G37R mice were treated with the metal complex diacetyl-bis(4-methylthiosemicarbazonato)zinc(II) [Zn(II)(atsm)]. Treatment resulted in an improvement in locomotor function and survival of the mice. However, biochemical analysis of spinal cord tissue collected from the mice revealed that the treatment did not increase overall Zn levels in the spinal cord nor the Zn content of SOD1. In contrast, overall levels of Cu in the spinal cord were elevated in the Zn(II)(atsm)-treated SOD1G37R mice and the Cu content of SOD1 was also elevated. Further experiments demonstrated transmetallation of Zn(II)(atsm) in the presence of Cu to form the Cu-analogue Cu(II)(atsm), indicating that the observed therapeutic effects for Zn(II)(atsm) in SOD1G37R mice may in fact be due to in vivo transmetallation and subsequent delivery of Cu. Copyright © 2015. Published by Elsevier Inc.

LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER LEVELS - PRESENTATION

EPA Science Inventory

Laboratory, pilot, and field data collected support the theoretical "cupric hydroxide" copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites, c...

LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER LEVELS

EPA Science Inventory

Laboratory, pilot, and field data collected support the theoretical “cupric hydroxide” copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites,...

Dietary copper in excess of nutritional requirement reduces plasma and breast muscle cholesterol of chickens.

PubMed

Bakalli, R I; Pesti, G M; Ragland, W L; Konjufca, V

1995-02-01

Male commercial broiler strain chickens were fed from hatching to 42 d of age either a control diet (based on corn and soybean meal) or the control diet supplemented with 250 mg copper/kg diet from cupric sulfate pentahydrate (for 35 or 42 d). Hypocholesterolemia (11.8% reduction) and decreased breast muscle cholesterol (20.4% reduction) were observed in copper-supplemented birds. There was a slight increase (P > .05) in breast muscle copper (14.5%), and all levels were very low (< .5 mg/kg). Feeding copper for 42 vs 35 d resulted in lower levels of cholesterol in the plasma (12.9 vs 10.8% reduction) and breast muscle (24.6 vs 16.2% reduction). Very similar results were found in two additional experiments in which hypocholesterolemia and reduced breast muscle cholesterol were associated with reduced plasma triglycerides and blood reduced glutathione. It is well known that hypercholesterolemia is a symptom of dietary copper deficiency. The data presented here indicate that blood and breast muscle cholesterol are inversely related to dietary copper in excess of the dietary requirement for maximal growth. The cholesterol content of the edible muscle tissue of broiler chickens can be reduced by approximately 25% after feeding a supranormal level of copper for 42 d without altering the growth of the chickens or substantially increasing the copper content of the edible meat.

Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation.

PubMed

Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

2015-12-01

Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

PubMed Central

Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

2016-01-01

Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies. PMID:26587712

Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

NASA Astrophysics Data System (ADS)

Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

2015-12-01

Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

Photogrammetry for environmental monitoring: the use of drones and hydrological models for detection of soil contaminated by copper.

PubMed

Capolupo, Alessandra; Pindozzi, Stefania; Okello, Collins; Fiorentino, Nunzio; Boccia, Lorenzo

2015-05-01

Campania Region of Southern Italy has a complex environmental situation, due to geogenic and anthropogenic soil pollution. Some of the pollutants such as copper are mobilized in the organic matter. It has been shown that wetlands provide physical as well as biogeochemical barriers against pollutants. Therefore, the objective of this study was to introduce and test an innovative approach able to predict copper accumulation points at plot scales, using a combination of aerial photos, taken by drones, micro-rill network modelling and wetland prediction indices usually used at catchment scales. Data were collected from an area measuring 4500 m(2) in Trentola Ducenta locality of Caserta Province of southern Italy. The photos processing with a fifth generation software for photogrammetry resulted in a high resolution Digital Elevation Model (DEM), used to study micro-rill processes. The DEM was also used to test the ability of Topographic Index (TI) and the Clima-Topographic Index (CTI) to predict copper sedimentation points at plot scale (0.1-10 ha) by comparing the map of the predicted and the actual copper distribution in the field. The DEM obtained with a resolution of 30 mm showed a high potential for the study of micro-rill processes and TI and CTI indices were able to predict zones of copper accumulation at a plot scale. Copyright © 2015 Elsevier B.V. All rights reserved.

40 CFR 141.88 - Monitoring requirements for lead and copper in source water.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the basis of tap samples collected in accordance with § 141.86 shall collect lead and copper source... value or be considered one-half the PQL. (b) Monitoring frequency after system exceeds tap water action level. Any system which exceeds the lead or copper action level at the tap shall collect one source...

Arsenic exposure levels in relation to different working departments in a copper mining and smelting plant

NASA Astrophysics Data System (ADS)

Sun, Qingshan; Song, Yingli; Liu, Shengnan; Wang, Fei; Zhang, Lin; Xi, Shuhua; Sun, Guifan

2015-10-01

The investigation was carried out to evaluate arsenic exposure and the urine metabolite profiles of workers with different working departments, including administration (Group1), copper ore mining (Group2), copper ore grinding (Group3), electrolytic procession (Group4) and copper smelting (Group5) in a Copper mining and processing plant in China. Information about characteristics of each subject was obtained by questionnaire and inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) in urine were determined. The highest urinary levels of iAs, MMA and DMA all were found in the Group 5. Group 4 workers had a higher iAs% and a lower PMI compared to Group 3. The urinary total As (TAs) levels of 54.7% subjects exceeded 50 μg/g Cr, and the highest percentage (93.3%) was found in Group 5, smelters. The results of the present study indicate that workers in copper production plant indeed exposed to As, especially for smelters and workers of electrolytic process.

Association of urinary metal profiles with altered glucose levels and diabetes risk: a population-based study in China.

PubMed

Feng, Wei; Cui, Xiuqing; Liu, Bing; Liu, Chuanyao; Xiao, Yang; Lu, Wei; Guo, Huan; He, Meian; Zhang, Xiaomin; Yuan, Jing; Chen, Weihong; Wu, Tangchun

2015-01-01

Elevated heavy metals and fasting plasma glucose (FPG) levels were both associated with increased risk of cardiovascular diseases. However, studies on the associations of heavy metals and essential elements with altered FPG and diabetes risk were limited or conflicting. The objective of this study was to evaluate the potential associations of heavy metals and essential trace elements with FPG and diabetes risk among general Chinese population. We conducted a cross-sectional study to investigate the associations of urinary concentrations of 23 metals with FPG, impaired fasting glucose (IFG) and diabetes among 2242 community-based Chinese adults in Wuhan. We used the false discovery rate (FDR) method to correct for multiple hypothesis tests. After adjusting for potential confounders, urinary aluminum, titanium, cobalt, nickel, copper, zinc, selenium, rubidium, strontium, molybdenum, cadmium, antimony, barium, tungsten and lead were associated with altered FPG, IFG or diabetes risk (all P< 0.05); arsenic was only dose-dependently related to diabetes (P< 0.05). After additional adjustment for multiple testing, titanium, copper, zinc, selenium, rubidium, tungsten and lead were still significantly associated with one or more outcomes (all FDR-adjusted P< 0.05). Our results suggest that multiple metals in urine are associated with FPG, IFG or diabetes risk. Because the cross-sectional design precludes inferences about causality, further prospective studies are warranted to validate our findings.

Effects of Dietary Copper and Zinc Supplementation on Growth Performance, Tissue Mineral Retention, Antioxidant Status, and Fur Quality in Growing-Furring Blue Foxes (Alopex lagopus).

PubMed

Liu, Zhi; Wu, Xuezhuang; Zhang, Tietao; Guo, Jungang; Gao, Xiuhua; Yang, Fuhe; Xing, Xiumei

2015-12-01

A 4×2 factorial experiment with four supplemental levels of copper (0, 20, 40, or 60 mg copper per kg dry matter) from copper sulfate and two supplemental levels of zinc (40 or 200 mg zinc per kg dry matter) from zinc sulfate was conducted to investigate the effects of dietary copper and zinc supplementation on growth performance, tissue mineral retention, antioxidant status, and fur quality in growing-furring blue foxes. One hundred and twenty healthy 15-week-old male blue foxes were randomly allocated to eight dietary treatments with 15 replicates per treatment for a 70-day trial from mid-September to pelting in December. The average daily gain and feed conversion ratio were increased with copper supplementation in the first 35 days as well as the overall period (P<0.05). In addition, copper supplementation tended to increase feed intake during the first 35 days (P<0.10). Diets supplemented with 200 mg/kg zinc did not affect body gain (P>0.10) and feed intake (P>0.10) but improved feed conversion (P<0.05) compared with those supplemented 40 mg/kg zinc throughout the experiment. No copper×zinc interaction was observed for growth performance except that a tendency (P=0.09) was found for feed intake in the first 35 days. Supplementation of copper or zinc improved crude fat digestibility (P<0.01) but had no effects on the digestibility of other nutrients. Fecal copper was increased with both copper (P<0.01) and zinc addition (P<0.05). However, fecal zinc was affected only by dietary zinc addition (P<0.01). Mineral contents in serum and kidney were not affected by dietary treatments (P>0.05). However, the level of copper in the liver was increased with copper supplementation (P<0.05) and tended to decrease with zinc supplementation (P=0.08). Dietary zinc addition tended to increase the activity of alkaline phosphatase (P=0.07). The activities of copper-zinc superoxide dismutase and catalase tended to increase by copper (P=0.08) and zinc addition (P=0.05). Moreover, a copper×zinc interaction was observed for catalase in the experiment (P<0.05). Serum malondialdehyde concentration decreased with the increasing of dietary copper and zinc levels (P<0.05). The activity of glutathione peroxidase tended to increase by copper addition (P=0.09). For fur quality, foxes fed diets supplemented with high copper had larger skin length and darker pelts than those fed the basal diet without copper addition (P<0.05). In conclusion, this study demonstrated that dietary copper and zinc supplementation can improve growth by increasing feed intake and improving fat digestibility. Additionally, copper and zinc can enhance the antioxidant capacity of blue foxes. This study also indicates that additional zinc up to 200 mg/kg did not exert significant adverse effects on the copper metabolism of growing-furring blue foxes.

Rapid Copper Acquisition by Developing Murine Mesothelioma: Decreasing Bioavailable Copper Slows Tumor Growth, Normalizes Vessels and Promotes T Cell Infiltration

PubMed Central

Crowe, Andrew; Jackaman, Connie; Beddoes, Katie M.; Ricciardo, Belinda; Nelson, Delia J.

2013-01-01

Copper, an essential trace element acquired through nutrition, is an important co-factor for pro-angiogenic factors including vascular endothelial growth factor (VEGF). Decreasing bioavailable copper has been used as an anti-angiogenic and anti-cancer strategy with promising results. However, the role of copper and its potential as a therapy in mesothelioma is not yet well understood. Therefore, we monitored copper levels in progressing murine mesothelioma tumors and analyzed the effects of lowering bioavailable copper. Copper levels in tumors and organs were assayed using atomic absorption spectrophotometry. Mesothelioma tumors rapidly sequestered copper at early stages of development, the copper was then dispersed throughout growing tumor tissues. These data imply that copper uptake may play an important role in early tumor development. Lowering bioavailable copper using the copper chelators, penicillamine, trientine or tetrathiomolybdate, slowed in vivo mesothelioma growth but did not provide any cures similar to using cisplatin chemotherapy or anti-VEGF receptor antibody therapy. The impact of copper lowering on tumor blood vessels and tumor infiltrating T cells was measured using flow cytometry and confocal microscopy. Copper lowering was associated with reduced tumor vessel diameter, reduced endothelial cell proliferation (reduced Ki67 expression) and lower surface ICAM/CD54 expression implying reduced endothelial cell activation, in a process similar to endothelial normalization. Copper lowering was also associated with a CD4+ T cell infiltrate. In conclusion, these data suggest copper lowering is a potentially useful anti-mesothelioma treatment strategy that slows tumor growth to provide a window of opportunity for inclusion of other treatment modalities to improve patient outcomes. PMID:24013775

The Bone Building Blues: Self-hardening copper-doped calcium phosphate cement and its in vitro assessment against mammalian cells and bacteria.

PubMed

Rau, Julietta V; Wu, Victoria M; Graziani, Valerio; Fadeeva, Inna V; Fomin, Alexander S; Fosca, Marco; Uskoković, Vuk

2017-10-01

A blue calcium phosphate cement with optimal self-hardening properties was synthesized by doping whitlockite (β-TCP) with copper ions. The mechanism and the kinetics of the cement solidification process were studied using energy dispersive X-ray diffraction and it was found out that hardening was accompanied by the phase transition from TCP to brushite. Reduced lattice parameters in all crystallographic directions resulting from the rather low (1:180) substitution rate of copper for calcium was consistent with the higher ionic radius of the latter. The lower cationic hydration resulting from the partial Ca→Cu substitution facilitated the release of constitutive hydroxyls and lowered the energy of formation of TCP from the apatite precursor at elevated temperatures. Addition of copper thus effectively inhibited the formation of apatite as the secondary phase. The copper-doped cement exhibited an antibacterial effect, though exclusively against Gram-negative bacteria, including E. coli, P. aeruginosa and S. enteritidis. This antibacterial effect was due to copper ions, as demonstrated by an almost negligible antibacterial effect of the pure, copper-free cement. Also, the antibacterial activity of the copper-containing cement was significantly higher than that of its precursor powder. Since there was no significant difference between the kinetics of the release of copper from the precursor TCP powder and from the final, brushite phase of the hardened cement, this has suggested that the antibacterial effect was not solely due to copper ions, but due to the synergy between cationic copper and a particular phase and aggregation state of calcium phosphate. Though inhibitory to bacteria, the copper-doped cement increased the viability of human glial E297 cells, murine osteoblastic K7M2 cells and especially human primary lung fibroblasts. That this effect was also due to copper ions was evidenced by the null effect on viability increase exhibited by the copper-free cements. The difference in the mechanism of protection of dehydratases in prokaryotes and eukaryotes was used as a rationale for explaining the hereby evidenced selectivity in biological response. It presents the basis for the consideration of copper as a dually effective ion when synergized with calcium phosphates: toxic for bacteria and beneficial for the healthy cells. Copyright © 2017 Elsevier B.V. All rights reserved.

The Role of Trace Elements in Tinnitus.

PubMed

Yaşar, Mehmet; Şahin, Mehmet İlhan; Karakükçü, Çiğdem; Güneri, Erhan; Doğan, Murat; Sağıt, Mustafa

2017-03-01

In this study, we aimed to investigate the role of three trace elements, namely, zinc, copper, and lead, in tinnitus by analyzing the serum level of copper and lead and both the serum and tissue level of zinc. Eighty patients, who applied to outpatient otolaryngology clinic with the complaints of having tinnitus, and 28 healthy volunteers were included. High-frequency audiometry was performed, and participants who had hearing loss according to the pure tone average were excluded; tinnitus frequency and loudness were determined and tinnitus reaction questionnaire scores were obtained from the patients. Of all the participants, serum zinc, copper, and lead values were measured; moreover, zinc levels were examined in hair samples. The levels of trace elements were compared between tinnitus and control groups. The level of copper was found to be significantly lower in the tinnitus group (p = 0.02), but there was no significant difference between the groups in terms of the levels of zinc, neither in serum nor in hair, and lead in serum (p > 0.05). The lack of trace elements, especially that of "zinc," have been doubted for the etiopathogenesis of tinnitus in the literature; however, we only found copper levels to be low in patients having tinnitus.

Mercury and other Mining-Related Contaminants in Ospreys along the Upper Clark Fork River, MT

NASA Astrophysics Data System (ADS)

Langner, H.; Domenech, R.; Greene, E.; Staats, M. F.

2010-12-01

Osprey (Pandion haliaetus) are widely recognized as bio-indicators of the health of aquatic ecosystems. Until the time of fledging, nestlings feed exclusively on fish caught within a few kilometers of the nest. Therefore, tissues of these young birds may reflect the level of contamination of local fish and more generally, the contamination status of the aquatic ecosystem they inhabit. Nests can often be accessed with a boom truck and obtaining small blood samples from the flightless chicks is fairly noninvasive. Ospreys are nesting along the Upper Clark Fork River, Montana, which is heavily contaminated with wastes left from a century of copper and precious metals mining. We have been monitoring the levels of priority pollutants (arsenic, cadmium, lead, copper, zinc, mercury and selenium) in Osprey chicks along a 250 km section of the river for four years. Objectives are to establish current contaminant status, pinpoint pollution hotspots, and assess the success of restoration efforts. Our results suggest that of highest concern may be the bioaccumulation of mercury with blood levels of up to 0.7 mg/L in the growing chicks. These concentrations are expected to increase many fold upon fledging as feather growth stops, which acts as the major sink for mercury. Interestingly, we found mercury levels increased in downstream direction, in contrast to concentrations of other pollutants. Reasons may be the different origin of mercury versus other contaminants and the distribution of wetlands where mercury can be transformed into highly bioavailable methylmercury. Blood levels of selenium are also elevated throughout the Upper Clark Fork River drainage. We discuss the implications for restoration and remediation of the Clark Fork River.

40 CFR 141.80 - General requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) NATIONAL PRIMARY DRINKING WATER REGULATIONS Control of Lead and Copper § 141.80 General requirements. (a... drinking water regulations for lead and copper. Unless otherwise indicated, each of the provisions of this... and copper action levels measured in samples collected at consumers' taps. (c) Lead and copper action...

Evaluation of Serum Levels of Zinc, Copper, Iron, and Zinc/Copper Ratio in Cutaneous Leishmaniasis

PubMed Central

Pourfallah, F; Javadian, S; Zamani, Z; Saghiri, R; Sadeghi, S; Zarea, B; Faiaz, Sh; Mirkhani, F; Fatemi, N

2009-01-01

Background: The purpose of this study was to evaluate the levels of zinc (Zn), copper (Cu), iron (Fe) and zinc/ copper ratio in the serum of patients with cutaneous leishmaniasis in Qom Province, center of Iran. Methods: Serum levels of zinc and copper were determined by flame atomic absorption spectrophotometer and serum iron concentration was measured by using an Auto Analyzer. The study group consisted of 60 patients with cutaneous leishmaniasis and the control group of 100 healthy volunteers from the same area who were not exposed to cutaneous leishmaniasis. Result: There were no statistically significant differences in age and body mass index between the two groups. Serum Zn (P< 0.001) and Fe (P< 0.05) levels were lower in patients with cutaneous leishmaniasis than the control group. We also found serum Cu concentration (P< 0.05) in the patient group was significantly higher than that of the control group. However, zinc/ copper ratio (P< 0.001) was lower in patients with cutaneous leishmaniasis than in the control group. Conclusion: Our data indicated that Zn/Cu ratio was significantly lower in patients with CL as compared to the controls. Earlier reports suggest that, this ratio imbalance could be a useful marker for immune dysfunction in leishmaniasis. There was also strong association of Zn, Cu and Fe with CL. It suggests the use of blood zinc, copper, iron concentration and the copper/zinc ratio (Zn/Cu), as a means for estimating the prognosis of CL. PMID:22808376

Serum ceruloplasmin protein expression and activity increases in iron-deficient rats and is further enhanced by higher dietary copper intake

PubMed Central

Ranganathan, Perungavur N.; Lu, Yan; Jiang, Lingli; Kim, Changae

2011-01-01

Increases in serum and liver copper content are noted during iron deficiency in mammals, suggesting that copper-dependent processes participate during iron deprivation. One point of intersection between the 2 metals is the liver-derived, multicopper ferroxidase ceruloplasmin (Cp) that is important for iron release from certain tissues. The current study sought to explore Cp expression and activity during physiologic states in which hepatic copper loading occurs (eg, iron deficiency). Weanling rats were fed control or low iron diets containing low, normal, or high copper for ∼ 5 weeks, and parameters of iron homeostasis were measured. Liver copper increased in control and iron-deficient rats fed extra copper. Hepatic Cp mRNA levels did not change; however, serum Cp protein was higher during iron deprivation and with higher copper consumption. In-gel and spectrophotometric ferroxidase and amine oxidase assays demonstrated that Cp activity was enhanced when hepatic copper loading occurred. Interestingly, liver copper levels strongly correlated with Cp protein expression and activity. These observations support the possibility that liver copper loading increases metallation of the Cp protein, leading to increased production of the holo enzyme. Moreover, this phenomenon may play an important role in the compensatory response to maintain iron homeostasis during iron deficiency. PMID:21768302

In vivo bioluminescence imaging reveals copper deficiency in a murine model of nonalcoholic fatty liver disease

PubMed Central

Heffern, Marie C.; Park, Hyo Min; Au-Yeung, Ho Yu; Van de Bittner, Genevieve C.; Ackerman, Cheri M.; Stahl, Andreas; Chang, Christopher J.

2016-01-01

Copper is a required metal nutrient for life, but global or local alterations in its homeostasis are linked to diseases spanning genetic and metabolic disorders to cancer and neurodegeneration. Technologies that enable longitudinal in vivo monitoring of dynamic copper pools can help meet the need to study the complex interplay between copper status, health, and disease in the same living organism over time. Here, we present the synthesis, characterization, and in vivo imaging applications of Copper-Caged Luciferin-1 (CCL-1), a bioluminescent reporter for tissue-specific copper visualization in living animals. CCL-1 uses a selective copper(I)-dependent oxidative cleavage reaction to release d-luciferin for subsequent bioluminescent reaction with firefly luciferase. The probe can detect physiological changes in labile Cu+ levels in live cells and mice under situations of copper deficiency or overload. Application of CCL-1 to mice with liver-specific luciferase expression in a diet-induced model of nonalcoholic fatty liver disease reveals onset of hepatic copper deficiency and altered expression levels of central copper trafficking proteins that accompany symptoms of glucose intolerance and weight gain. The data connect copper dysregulation to metabolic liver disease and provide a starting point for expanding the toolbox of reactivity-based chemical reporters for cell- and tissue-specific in vivo imaging. PMID:27911810

The effect of gastrointestinal parasitism on blood copper and hemoglobin levels in sheep

PubMed Central

2005-01-01

Abstract Endoparasitism is a problem in Trinidad, as it is in most tropical countries. Parasite infection has been suspected to contribute to the pathogenesis of swayback disease (which is also prevalent in Trinidad), but the mode of action has not been clearly defined, although it has been suggested that parasites interfere with the absorption of copper from the gastrointestinal tract. The objectives of the study were to assess the effect of endoparasitism on blood copper levels and hemoglobin (Hb) concentration in sheep in Trinidad. Copper was administered intramuscularly to parasite infected and noninfected animals. The results showed that parasitism has a depressing effect on blood copper and Hb levels, even when administered parenterally. It is concluded that parasitism can aggravate existing hypocupremia and possibly influence the expression of swayback disease. PMID:16363328

The Effect of Helicobacter pylori Eradication on the Levels of Essential Trace Elements

PubMed Central

Wu, Meng-Chieh; Huang, Chun-Yi; Kuo, Fu-Chen; Hsu, Wen-Hung; Wang, Sophie S. W.; Shih, Hsiang-Yao; Liu, Chung-Jung; Chen, Yen-Hsu; Wu, Deng-Chyang; Huang, Yeou-Lih; Lu, Chien-Yu

2014-01-01

Objective. This study was designed to compare the effect of Helicobacter pylori (H. pylori) infection treatment on serum zinc, copper, and selenium levels. Patients and Methods. We measured the serum zinc, copper, and selenium levels in H. pylori-positive and H. pylori-negative patients. We also evaluated the serum levels of these trace elements after H. pylori eradication. These serum copper, zinc, and selenium levels were determined by inductively coupled plasma mass spectrometry. Results. Sixty-three H. pylori-positive patients and thirty H. pylori-negative patients were studied. Serum copper, zinc, and selenium levels had no significant difference between H. pylori-positive and H. pylori-negative groups. There were 49 patients with successful H. pylori eradication. The serum selenium levels were lower after successful H. pylori eradication, but not significantly (P = 0.06). There were 14 patients with failed H. pylori eradication. In this failed group, the serum selenium level after H. pylori eradication therapy was significantly lower than that before H. pylori eradication therapy (P < 0.05). The serum zinc and copper levels had no significant difference between before and after H. pylori eradication therapies. Conclusion. H pylori eradication regimen appears to influence the serum selenium concentration (IRB number: KMUH-IRB-20120327). PMID:25548772

Inexpensive Method of Testing Ambient and Thermally Elevated Resistive and Piezoresistive Thin-Film Pressure Gauges

NASA Astrophysics Data System (ADS)

Armstrong, Christopher; Rae, Philip; Heatwole, Eric; Tasker, Douglas; Los Alamos National Labortatory Team

2017-06-01

Manganin is an alloy that changes resistance when subjected to high-pressure, but is insensitive to temperature changes. Resistance curves as a function of pressure for these gauges have been established. Another commonly used piezoresistive pressure sensor are thin-film carbon gauges, which are more pressure sensitive than manganin gauges. Carbon gauge response in high temperature is not well quantified. The current research is focused on verifying these established resistance curves as well as verifying this specific experimental configuration. In this research the carbon gauges' resistance change is measured for thermally elevated gauges. In this setup a 20 mm caliber gun drove planar copper projectiles at the gauge, which was embedded in a copper anvil. The Hugoniot relationship allows for a comparison between observed and theoretical pressure over a pressure range 5 to 20 GPa for manganin gauges and 1 to 5 GPa for carbon gauges. The comparison between the data obtained in this research and that of others shows that the pressure-resistance curve of manganin does to not vary between lots of manganin. Additionally, the data shows that this setup is a relatively inexpensive quick means of testing gauge response to high-pressure shocks and is suitable for elevated temperature.

Elevated corrosion rates and hydrogen sulfide in homes with 'Chinese Drywall'.

PubMed

Allen, Joseph G; MacIntosh, David L; Saltzman, Lori E; Baker, Brian J; Matheson, Joanna M; Recht, Joel R; Minegishi, Taeko; Fragala, Matt A; Myatt, Theodore A; Spengler, John D; Stewart, James H; McCarthy, John F

2012-06-01

In December 2008, the U.S. Consumer Product Safety Commission (CPSC) began receiving reports about odors, corrosion, and health concerns related to drywall originating from China. In response, a detailed environmental health and engineering evaluation was conducted of 41 complaint and 10 non-complaint homes in the Southeast U.S. Each home investigation included characterization of: 1) drywall composition; 2) indoor and outdoor air quality; 3) temperature, moisture, and building ventilation; and 4) copper and silver corrosion rates. Complaint homes had significantly higher hydrogen sulfide concentrations (mean 0.82 vs.

Heavy metal pollution among autoworkers. II. Cadmium, chromium, copper, manganese, and nickel.

PubMed Central

Clausen, J; Rastogi, S C

1977-01-01

Garages and auto-repair workshops may be polluted with other heavy metals besides lead. Blood of autoworkers with high lead content was analysed for cadmium, chromium, copper manganese, nickel, ALAD activity and carboxyhaemoglobin level. Cadmium and copper levels in blood of autoworkers were comparable with those of the control subjects while chroimium and nickel levels were significantly higher (P less than 0-01 for both metals), and scattered raised values of manganese were found. There was no significant mutual correlation between levels of various heavy metals determined in whole blood. High copper levels were slightly related to decreasing ALAD activity (P less than 0-1). Nineteen per cent of autoworkers were found to have an abnormally blood level of carboxyhaemoglobin. The amount of particulate heavy metal in autoworkshop air was not related to biochemical abnormalities found in the autoworkers. Various sources of pollution of these heavy metals in autoworkshops are discussed. PMID:71915

Gene expression patterns in the progression of canine copper-associated chronic hepatitis

PubMed Central

Dirksen, Karen; Spee, Bart; Penning, Louis C.; van den Ingh, Ted S. G. A. M.; Burgener, Iwan A.; Watson, Adrian L.; Groot Koerkamp, Marian; Rothuizen, Jan

2017-01-01

Copper is an essential trace element, but can become toxic when present in abundance. The severe effects of copper-metabolism imbalance are illustrated by the inherited disorders Wilson disease and Menkes disease. The Labrador retriever dog breed is a novel non-rodent model for copper-storage disorders carrying mutations in genes known to be involved in copper transport. Besides disease initiation and progression of copper accumulation, the molecular mechanisms and pathways involved in progression towards copper-associated chronic hepatitis still remain unclear. Using expression levels of targeted candidate genes as well as transcriptome micro-arrays in liver tissue of Labrador retrievers in different stages of copper-associated hepatitis, pathways involved in progression of the disease were studied. At the initial phase of increased hepatic copper levels, transcriptomic alterations in livers mainly revealed enrichment for cell adhesion, developmental, inflammatory, and cytoskeleton pathways. Upregulation of targeted MT1A and COMMD1 mRNA shows the liver’s first response to rising intrahepatic copper concentrations. In livers with copper-associated hepatitis mainly an activation of inflammatory pathways is detected. Once the hepatitis is in the chronic stage, transcriptional differences are found in cell adhesion adaptations and cytoskeleton remodelling. In view of the high similarities in copper-associated hepatopathies between men and dog extrapolation of these dog data into human biomedicine seems feasible. PMID:28459846

A Combined Ecological and Epidemiologic Investigation of Metals Exposure amongst Indigenous Peoples Near the Marlin Mine in Western Guatemala

PubMed Central

Basu, Niladri; Abare, Marce; Buchanan, Susan; Cryderman, Diana; Nam, Dong-Ha; Sirkin, Susannah; Schmitt, Stefan; Hu, Howard

2016-01-01

In August 2009 a combined epidemiological and ecological pilot study was conducted to investigate allegations of human rights abuses in the form of exposures to toxic metals experienced by mine workers and Indigenous Mam Mayan near the Marlin Mine in Guatemala. In the human study there were no differences in blood and urine metals when comparing five mine workers with eighteen non-mine workers, and there were no discernible relationships between metals exposures and self-reported health measures in any study group. On the other hand, individuals residing closest to the mine had significantly higher levels of certain metals (urinary mercury, copper, arsenic, zinc) when compared to those living further away. Levels of blood aluminum, manganese, and cobalt were elevated in comparison to established normal ranges in many individuals; however, there was no apparent relationship to proximity to the mine or occupation, and thus are of unclear significance. In the ecological study, several metals (aluminum, manganese, cobalt) were found significantly elevated in the river water and sediment sites directly below the mine when compared to sites elsewhere. When the results of the human and ecological results are combined, they suggest that exposures to certain metals may be elevated in sites near the mine but it is not clear if the current magnitude of these elevations poses a significant threat to health. The authors conclude that more robust studies are needed while parallel efforts to minimize the ecological and human impacts of mining proceed. This is critical particularly as the impact of the exposures found could be greatly magnified by expected increases in mining activity over time, synergistic toxicity between metals, and susceptibility for the young and those with pre-existing disease. PMID:20952048

GRCop-84: A High Temperature Copper-based Alloy For High Heat Flux Applications

NASA Technical Reports Server (NTRS)

Ellis, David L.

2005-01-01

While designed for rocket engine main combustion chamber liners, GRCop-84 (Cu-8 at.% Cr-4 at.% Nb) offers potential for high heat flux applications in industrial applications requiring a temperature capability up to approximately 700 C (1292 F). GRCop-84 is a copper-based alloy with excellent elevated temperature strength, good creep resistance, long LCF lives and enhanced oxidation resistance. It also has a lower thermal expansion than copper and many other low alloy copper-based alloys. GRCop-84 can be manufactured into a variety of shapes such as tubing, bar, plate and sheet using standard production techniques and requires no special production techniques. GRCop-84 forms well, so conventional fabrication methods including stamping and bending can be used. GRCop-84 has demonstrated an ability to be friction stir welded, brazed, inertia welded, diffusion bonded and electron beam welded for joining to itself and other materials. Potential applications include plastic injection molds, resistance welding electrodes and holders, permanent metal casting molds, vacuum plasma spray nozzles and high temperature heat exchanger applications.

Aquatic Life Criteria - Copper

EPA Pesticide Factsheets

Documents pertain to Aquatic Life Ambient Water Quality criteria for Copper (2007 Freshwater, 2016 Estuarine/marine). These documents contain the safe levels of Copper in water that should protect to the majority of species.

Acute gastrointestinal effects of graded levels of copper in drinking water.

PubMed Central

Pizarro, F; Olivares, M; Uauy, R; Contreras, P; Rebelo, A; Gidi, V

1999-01-01

The objective of this study was to determine the acute gastrointestinal effects caused by the consumption of drinking water containing graded levels of added copper. Sixty healthy, adult women were randomly assigned to receive copper [Cu(II)] at four concentrations in their drinking water following a Latin-square design. Each group (n = 15) received tap water with no added copper, 1, 3, and 5 mg Cu/l of added copper sulfate for a 2-week study period, followed by 1 week of standard tap water. The subjects recorded their water consumption and gastrointestinal symptoms daily on a special form. The average daily consumption of water was 1.64 liters per subject, regardless of the amount of copper added. Final serum copper, ceruloplasmin, and liver enzymes were measured in all subjects and were not different from baseline concentrations. Twenty-one subjects (35%) recorded gastrointestinal disturbances sometime during the study, 9 had diarrhea, some with abdominal pain and vomiting, and 12 subjects presented abdominal pain, nausea, or vomiting. There was no association between copper levels in drinking water and diarrhea. However, nausea, abdominal pain, or vomiting were significantly related to copper concentrations in water. The recorded incidence rate of these symptoms was 5, 2, 17, and 15% while ingesting water with 0, 1, 3, and 5 mg Cu/l, respectively (overall [chi]2 = 11.3, p<0.01; Cu [less than/equal to]1 mg/l versus Cu [Greater than/equal to]3 mg/l, [chi]2, p<0.01). When subjects interrupted their consumption of drinking water with added copper, most symptoms disappeared. We conclude that under the conditions of the study, there was no association between aggregate copper in drinking water within the range of 0-5 mg/l and diarrhea, but a [Greater than/equal to]3 mg Cu/l level of ionized copper was associated with nausea, abdominal pain, or vomiting. Additional studies with sufficient numbers of subjects are needed to define thresholds for specific gastrointestinal symptoms with precision and to extrapolate these results to the population at large. Images Figure 1 Figure 2 PMID:9924006

Late Quaternary megafloods from Glacial Lake Atna, Southcentral Alaska, U.S.A.

NASA Astrophysics Data System (ADS)

Wiedmer, Michael; Montgomery, David R.; Gillespie, Alan R.; Greenberg, Harvey

2010-05-01

Geomorphic, stratigraphic, geotechnical, and biogeographic evidence indicate that failure of a Pleistocene ice dam between 15.5 and 26 ka generated a megaflood from Glacial Lake Atna down the Matanuska Valley. While it has long been recognized that Lake Atna occupied ≥ 9000 km 2 of south-central Alaska's Copper River Basin, little attention has focused on the lake's discharge locations and behaviors. Digital elevation model and geomorphic analyses suggest that progressive lowering of the lake level by decanting over spillways exposed during glacial retreat led to sequential discharges down the Matanuska, Susitna, Tok, and Copper river valleys. Lake Atna's size, ˜ 50 ka duration, and sequential connection to four major drainages likely made it a regionally important late Pleistocene freshwater refugium. We estimate a catastrophic Matanuska megaflood would have released 500-1400 km 3 at a maximum rate of ≥ 3 × 10 6 m 3 s - 1 . Volumes for the other outlets ranged from 200 to 2600 km 3 and estimated maximum discharges ranged from 0.8 to 11.3 × 10 6 m 3 s - 1 , making Lake Atna a serial generator of some of the largest known freshwater megafloods.

Short-term acute hypercapnia affects cellular responses to trace metals in the hard clams Mercenaria mercenaria.

PubMed

Ivanina, Anna V; Beniash, Elia; Etzkorn, Markus; Meyers, Tiffany B; Ringwood, Amy H; Sokolova, Inna M

2013-09-15

Estuarine and coastal habitats experience large fluctuations of environmental factors such as temperature, salinity, partial pressure of CO2 ( [Formula: see text] ) and pH; they also serve as the natural sinks for trace metals. Benthic filter-feeding organisms such as bivalves are exposed to the elevated concentrations of metals in estuarine water and sediments that can strongly affect their physiology. The effects of metals on estuarine organisms may be exacerbated by other environmental factors. Thus, a decrease in pH caused by high [Formula: see text] (hypercapnia) can modulate the effects of trace metals by affecting metal bioavailability, accumulation or binding. To better understand the cellular mechanisms of interactions between [Formula: see text] and trace metals in marine bivalves, we exposed isolated mantle cells of the hard clams (Mercenaria mercenaria) to different levels of [Formula: see text] (0.05, 1.52 and 3.01 kPa) and two major trace metal pollutants - cadmium (Cd) and copper (Cu). Elevated [Formula: see text] resulted in a decrease in intracellular pH (pHi) of the isolated mantle cells from 7.8 to 7.4. Elevated [Formula: see text] significantly but differently affected the trace metal accumulation by the cells. Cd uptake was suppressed at elevated [Formula: see text] levels while Cu accumulation has greatly accelerated under hypercapnic conditions. Interestingly, at higher extracellular Cd levels, labile intracellular Cd(2+) concentration remained the same, while intracellular levels of free Zn(2+) increased suggesting that Cd(2+) substitutes bound Zn(2+) in these cells. In contrast, Cu exposure did not affect intracellular Zn(2+) but led to a profound increase in the intracellular levels of labile Cu(2+) and Fe(2+). An increase in the extracellular concentrations of Cd and Cu led to the elevated production of reactive oxygen species under the normocapnic conditions (0.05 kPa [Formula: see text] ); surprisingly, this effect was mitigated in hypercapnia (1.52 and 3.01 kPa). Overall, our data reveal complex and metal-specific interactions between the cellular effects of trace metals and [Formula: see text] in clams and indicate that variations in environmental [Formula: see text] may modulate the biological effects of trace metals in marine organisms. Copyright © 2013 Elsevier B.V. All rights reserved.

Copper aluminate spinel in the stabilization and detoxification of simulated copper-laden sludge.

PubMed

Tang, Yuanyuan; Shih, Kaimin; Chan, King

2010-06-01

This study aims to evaluate the feasibility of stabilizing copper-laden sludge by the application of alumina-based ceramic products. The processing temperature, material leaching behaviour, and the effect of detoxification were investigated in detail. CuO was used to simulate the copper-laden sludge and X-ray Diffraction was performed to monitor the incorporation of copper into the copper aluminate spinel (CuAl(2)O(4)) phase in ceramic products. It was found that the development of CuAl(2)O(4) increased with elevating temperatures up to and including 1000 degrees C in the 3h short-sintering scheme. When the sintering temperature went above 1000 degrees C, the CuAl(2)O(4) phase began to decompose due to the high temperature transformation to CuAlO(2). The leachability and leaching behaviour of CuO and CuAl(2)O(4) were compared by usage of a prolonged leaching test modified from US EPA's toxicity characteristic leaching procedure. The leaching results show that CuAl(2)O(4) is superior to CuO for the purpose of copper immobilization over longer leaching periods. Furthermore, the detoxification effect of CuAl(2)O(4) was tested through bacterial adhesion with Escherichia coli K12, and the comparison of bacterial adhesion on CuO and CuAl(2)O(4) surfaces shows the beneficial detoxification effect in connection with the formation of the CuAl(2)O(4) spinel. This study demonstrates the feasibility of transforming copper-laden sludge into the spinel phase by using readily available and inexpensive ceramic materials, and achieving a successful reduction of metal mobility and toxicity.

Copper mediated polymerization without external deoxygenation or oxygen scavengers.

PubMed

Liarou, Evelina; Whitfield, Richard; Anastasaki, Athina; Engelis, Nikolaos G; Jones, Glen R; Velonia, Kelly; Haddleton, David

2018-05-14

Overcoming the challenge of rigorous deoxygenation in copper mediated controlled radical polymerization processes (e.g. ATRP), we report a simple Cu(0)-RDRP system in the absence of external additives (e.g. reducing agents, enzymes etc.). By simply adjusting the headspace of the reaction vessel, a wide range of monomers, namely acrylates, methacrylates, acrylamides and styrene, can be polymerized in a controlled manner yielding polymers with low dispersities, near-quantitative conversions and high end group fidelity. Significantly, this approach is scalable (~ 125 g), tolerant to elevated temperatures, compatible with both organic and aqueous media and does not rely on external stimuli which may limit the monomer pool. The robustness and versatility of this methodology is further demonstrated by the applicability to a number of other copper mediated techniques including conventional ATRP and light-mediated approaches. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wilson’s disease: A review of what we have learned

PubMed Central

Rodriguez-Castro, Kryssia Isabel; Hevia-Urrutia, Francisco Javier; Sturniolo, Giacomo Carlo

2015-01-01

Wilson’s disease (WD), which results from the defective ATP7B protein product, is characterized by impaired copper metabolism and its clinical consequences vary from an asymptomatic state to fulminant hepatic failure, chronic liver disease with or without cirrhosis, neurological, and psychiatric manifestations. A high grade of suspicion is warranted to not miss cases of WD, especially less florid cases with only mild elevation of transaminases, or isolated neuropsychiatric involvement. Screening in first and second relatives of index cases is mandatory, and treatment must commence upon establishment of diagnosis. Treatment strategies include chelators such as D-penicillamine and trientine, while zinc salts act as inductors of methallothioneins, which favor a negative copper balance and a reduction of free plasmatic copper. As an orphan disease, research is lacking in this field, especially regarding therapeutic strategies which are associated with better patient compliance and which could eventually also reverse established injury. PMID:26692151

Copper ions stimulate the proliferation of hepatic stellate cells via oxygen stress in vitro.

PubMed

Xu, San-qing; Zhu, Hui-yun; Lin, Jian-guo; Su, Tang-feng; Liu, Yan; Luo, Xiao-ping

2013-02-01

This study examined the effect of copper ions on the proliferation of hepatic stellate cells (HSCs) and the role of oxidative stress in this process in order to gain insight into the mechanism of hepatic fibrosis in Wilson's disease. LX-2 cells, a cell line of human HSCs, were cultured in vitro and treated with different agents including copper sulfate, N-acetyl cysteine (NAC) and buthionine sulfoximine (BSO) for different time. The proliferation of LX-2 cells was measured by non-radioactive cell proliferation assay. Real-time PCR and Western blotting were used to detect the mRNA and protein expression of platelet-derived growth factor receptor β subunit (PDGFβR), ELISA to determine the level of glutathione (GSH) and oxidized glutathione (GSSG), dichlorofluorescein assay to measure the level of reactive oxygen species (ROS), and lipid hydroperoxide assay to quantify the level of lipid peroxide (LPO). The results showed that copper sulfate over a certain concentration range could promote the proliferation of LX-2 cells in a time- and dose-dependent manner. The effect was most manifest when LX-2 cells were treated with copper sulfate at a concentration of 100 μmol/L for 24 h. Additionally, copper sulfate could dose-dependently increase the levels of ROS and LPO, and decrease the ratio of GSH/GSSG in LX-2 cells. The copper-induced increase in mRNA and protein expression of PDGFβR was significantly inhibited in LX-2 cells pre-treated with NAC, a precursor of GSH, and this phenomenon could be reversed by the intervention of BSO, an inhibitor of NAC. It was concluded that copper ions may directly stimulate the proliferation of HSCs via oxidative stress. Anti-oxidative stress therapies may help suppress the copper-induced activation and proliferation of HSCs.

The influence of duckweed species diversity on ecophysiological tolerance to copper exposure.

PubMed

Zhao, Zhao; Shi, Huijuan; Duan, Dongzhu; Li, Hongmei; Lei, Tingwen; Wang, Maolin; Zhao, Hai; Zhao, Yun

2015-07-01

In excess, copper is toxic to plants. In the plants, Landoltia punctata and Lemna minor grown in mixed and monoculture, the effects of exposure to varying concentrations of copper (0.01, 0.1, 0.5 and 1mgL(-1) Cu) for seven days were assessed by measuring changes in the chlorophyll, protein and malondialdehyde (MDA) content, catalase (CAT), superoxide dismutase (SOD) and ascorbate peroxidase (APX) activity. According to results, Cu levels in plants increased with increasing Cu concentration. The level of photosynthetic pigments and crude proteins decreased only upon exposure to high Cu concentrations. However, the starch and malondialdehyde (MDA) content increased. These results suggested a stress alleviation that was possibly the result of antioxidants such as CAT and SOD, the activities of which increased with increasing Cu levels. APX activity increased in L. punctata, but decreased in L. minor, under monoculture or mixed culture conditions. In addition, the duckweed in mixed culture exhibited increased antioxidant enzyme activities which provide increased resistance to copper in moderate copper concentrations. As the copper concentration increased, the duckweed in the mixed culture limited the uptake of copper to avoid toxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

Copper Indium Gallium Diselenide Solar Cells | Photovoltaic Research | NREL

Science.gov Websites

primary research areas that are currently our focus are the following: Understanding effects of material . Such metastable effects frustrate the repeatable and accurate measurement of a module's performance in by perturbing the voltage bias or temperature. Another associated challenge is that elevated

Fabrication of GRCop-84 Rocket Thrust Chambers

NASA Technical Reports Server (NTRS)

Loewenthal, William; Ellis, David

2006-01-01

GRCop-84, a copper alloy, Cu-8 at% Cr-4 at% Nb developed at NASA Glenn Research Center for regenerative1y cooled rocket engine liners has excellent combinations of elevated temperature strength, creep resistance, thermal conductivity and low cycle fatigue. GRCop-84 is produced from pre-alloyed atomized powder and has been fabricated into plate, sheet and tube forms as well as near net shapes. Fabrication processes to produce demonstration rocket combustion chambers will be presented and includes powder production, extruding, rolling, forming, friction stir welding, and metal spinning. GRCop-84 has excellent workability and can be readily fabricated into complex components using conventional powder and wrought metallurgy processes. Rolling was examined in detail for process sensitivity at various levels of total reduction, rolling speed and rolling temperature representing extremes of commercial processing conditions. Results indicate that process conditions can range over reasonable levels without any negative impact to properties.

Fabrication of GRCop-84 Rocket Thrust Chambers

NASA Technical Reports Server (NTRS)

Loewenthal, William S.; Ellis, David L.

2005-01-01

GRCop-84, a copper alloy, Cu-8 at% Cr-4 at% Nb developed at NASA Glenn Research Center for regeneratively cooled rocket engine liners has excellent combinations of elevated temperature strength, creep resistance, thermal conductivity and low cycle fatigue. GRCop-84 is produced from prealloyed atomized powder and has been fabricated into plate, sheet and tube forms as well as near net shapes. Fabrication processes to produce demonstration rocket combustion chambers will be presented and includes powder production, extruding, rolling, forming, friction stir welding, and metal spinning. GRCop-84 has excellent workability and can be readily fabricated into complex components using conventional powder and wrought metallurgy processes. Rolling was examined in detail for process sensitivity at various levels of total reduction, rolling speed and rolling temperature representing extremes of commercial processing conditions. Results indicate that process conditions can range over reasonable levels without any negative impact to properties.

Thermal regime, predation danger and the early marine exit of sockeye salmon Oncorhynchus nerka.

PubMed

Katinic, P J; Patterson, D A; Ydenberg, R C

2015-01-01

Marine exit timing of sockeye salmon Oncorhynchus nerka populations on the Haida Gwaii Archipelago, British Columbia, Canada, is described, with specific focus on Copper Creek. Marine exit in Copper Creek occurs > 130 days prior to spawning, one of the longest adult freshwater residence periods recorded for any O. nerka population. Copper Creek presents an easy upstream migration, with mild water temperatures (7 to 14°  C), short distance (13·1 km) and low elevation gain (41 m) to the lake where fish hold prior to spawning. An energetic model estimates that <1% of the initial energy reserve is required for upstream migration, compared with 62% for lake holding and 38% for reproductive development. Historical records suggest that it is unlikely that water temperature in any of the O.nerka streams in Haida Gwaii has ever exceeded the presumed temperature threshold (19° C) for early marine exit. Although it is not impossible that the thermal tolerance of Copper Creek O.nerka is very low, the data presented here appear inconsistent with thermal avoidance as an explanation for the early marine exit timing in Copper Creek and in three other populations on the archipelago with early marine exit. © 2014 The Fisheries Society of the British Isles.

Effects of Copper Oxide Nanoparticles on Antioxidant Enzyme Activities and on Tissue Accumulation of Oreochromis niloticus.

PubMed

Tunçsoy, Mustafa; Duran, Servet; Ay, Özcan; Cicik, Bedii; Erdem, Cahit

2017-09-01

Accumulation of copper oxide nanoparticles (CuO NPs) in gill, liver and muscle tissues of Oreochromis niloticus and its effects on superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities in gill and liver tissues were studied after exposing the fish to 20 µg/L Cu over 15 days. Copper levels and enzyme activities in tissues were determined using spectrophotometric (ICP-AES and UV) techniques respectively. No mortality was observed during the experiments. Copper levels increased in gill and liver tissues of O. niloticus compared to control when exposed to CuO NPs whereas exposure to metal had no effect on muscle level at the end of the exposure period. Highest accumulation of copper was observed in liver while no accumulation was detected in muscle tissue. SOD, CAT activities decreased and GPx activity increased in gill and liver tissues when exposed to CuO NPs.

The influence of long-term copper contaminated agricultural soil at different pH levels on microbial communities and springtail transcriptional regulation.

PubMed

de Boer, Tjalf E; Taş, Neslihan; Braster, Martin; Temminghoff, Erwin J M; Röling, Wilfred F M; Roelofs, Dick

2012-01-03

Copper has long been applied for agricultural practises. Like other metals, copper is highly persistent in the environment and biologically active long after its use has ceased. Here we present a unique study on the long-term effects (27 years) of copper and pH on soil microbial communities and on the springtail Folsomia candida an important representative of the soil macrofauna, in an experiment with a full factorial, random block design. Bacterial communities were mostly affected by pH. These effects were prominent in Acidobacteria, while Actinobacteria and Gammaroteobacteria communities were affected by original and bioavailable copper. Reproduction and survival of the collembolan F. candida was not affected by the studied copper concentrations. However, the transcriptomic responses to copper reflected a mechanism of copper transport and detoxification, while pH exerted effects on nucleotide and protein metabolism and (acute) inflammatory response. We conclude that microbial community structure reflected the history of copper contamination, while gene expression analysis of F. candida is associated with the current level of bioavailable copper. The study is a first step in the development of a molecular strategy aiming at a more comprehensive assessment of various aspects of soil quality and ecotoxicology.

Effects of Water Quality and Orthophosphate on Surface Characteristics of Cu Corrosion in Drinking Water using Atomic Force Microscopy

EPA Science Inventory

Since the passage of the Lead and Copper Rule (LCR) in 1991, researchers have examined the effects of water chemistry on the solubility of copper to establish best approaches for reducing copper levels. Despite recent developments, important gaps still exist regarding copper cor...

Insights into the mechanism of copper-tolerance in Fibroporia radiculosa: The biosynthesis of oxalate

Treesearch

Katie Jenkins; Carol A. Clausen; Frederick Green; Susan V. Diehl

2015-01-01

Copper is currently used as the key component in wood preservatives despite the known tolerance of many brown-rot Basidiomycetes. Copper-tolerant fungi, like Fibroporia radiculosa, produce and accumulate high levels of oxalate when exposed to copper. To gain insight into the mechanism of oxalate production, four F. radiculosa...

Circulation of copper in the biotic compartments of a freshwater dammed reservoir.

PubMed

Vinot, I; Pihan, J C

2005-01-01

This study concerns a chronic copper release in an aquatic ecosystem: Mirgenbach reservoir; which is characterized by high salinity, conductivity and hardness, a eutrophic state and a high temperature. To study the bioavailability of copper in the biotic compartments, the sampling covered the entire food chain (phyto- and zooplankton, macroalgae, aquatic plants, crustaceans, mollusks, and fish). Of the organisms present, the filter feeder Dreissena polymorpha, the detritivorous Bithynia tentaculata and Orconectes limosus were most contaminated by copper. The level of copper found in fish was the lowest. Body copper concentrations recorded in the present study show large variability between species even in some that are closely related. In most cases, however, the metal handling strategy, feeding habits, morphology and ecology can, at least partially, explain the metal content recorded. Pollution factors have been used to assess the state of contamination of the food chain. This study showed finally that the copper in the lake is bioavailable and bioaccumulated by organisms up to high levels and some effects of long-term toxicity of copper on benthic community and planktonic biomass were pointed out.

Enzymatic mechanism of oxalate production in the TCA and glyoxylate pathways using various isolates of Antrodia radiculosa

Treesearch

K.M. Jenkins; S.V. Diehl; C.A. Clausen; F. Green

2011-01-01

Brown-rot fungi produce oxalate in large amounts; however, levels of accumulation and function vary by species. Copper-tolerant fungi, like Antrodia radiculosa, produce and accumulate high levels of oxalate in response to copper. Oxalate biosynthesis in copper-tolerant fungi has been linked to the glyoxylate and tricarboxylic acid (TCA) cycles. Within these two cycles...

Exogenous addition of histidine reduces copper availability in the yeast Saccharomyces cerevisiae.

PubMed

Watanabe, Daisuke; Kikushima, Rie; Aitoku, Miho; Nishimura, Akira; Ohtsu, Iwao; Nasuno, Ryo; Takagi, Hiroshi

2014-07-07

The basic amino acid histidine inhibited yeast cell growth more severely than lysine and arginine. Overexpression of CTR1 , which encodes a high-affinity copper transporter on the plasma membrane, or addition of copper to the medium alleviated this cytotoxicity. However, the intracellular level of copper ions was not decreased in the presence of excess histidine. These results indicate that histidine cytotoxicity is associated with low copper availability inside cells, not with impaired copper uptake. Furthermore, histidine did not affect cell growth under limited respiration conditions, suggesting that histidine cytotoxicity is involved in deficiency of mitochondrial copper.

2016 Draft Estuarine/Marine Copper Aquatic Life Ambient Water Quality Criteria

EPA Pesticide Factsheets

Documents pertain to Aquatic Life Ambient Water Quality criteria for Copper (2016 Estuarine/marine). These documents contain the safe levels of Copper in water that should protect to the majority of species.

Robust p-type doping of copper oxide using nitrogen implantation

NASA Astrophysics Data System (ADS)

Jorge, Marina; Polyakov, Stanislav M.; Cooil, Simon; Schenk, Alex K.; Edmonds, Mark; Thomsen, Lars; Mazzola, Federico; Wells, Justin W.

2017-07-01

We demonstrate robust p-type doping of Cu2O using low/medium energy ion implantation. Samples are made by controlled oxidation of annealed Cu metal foils, which results in Cu2O with levels of doping close to intrinsic. Samples are then implanted with nitrogen ions using a kinetic energy in the few keV range. Using this method, we are able to produce very high levels of doping, as evidenced by a 350 meV shift in the Fermi level towards the VB maximum. The robustness of the nitrogen implanted samples are tested by exposing them to atmospheric contaminants, and elevated temperatures. The samples are found to survive an increase in temperature of many hundreds of degrees. The robustness of the samples, combined with the fact that the materials used are safe, abundant and non-toxic and that the methods used for the growth of Cu2O and N+ implantation are simple and cheap to implement industrially, underlines the potential of Cu2O:N for affordable intermediate band photovoltaics.

Zinc in denture adhesive: a rare cause of copper deficiency in a patient on home parenteral nutrition

PubMed Central

Prasad, Rakesh; Hawthorne, Barney; Durai, Dharmaraj; McDowell, Ian

2015-01-01

A 65-year-old woman with Crohn's disease, who had been on home parenteral nutrition for many years, presented with perioral paraesthesia and a burning sensation in the mouth. Initial blood tests including serum ferritin, vitamin B12 and folate, were normal apart from mild pancytopaenia. Serum copper was low, in spite of receiving regular copper in her parenteral feeds. The copper in her parenteral feeds was increased initially, but when it did not improve, she was started on weekly intravenous copper infusions. She was using dental adhesive, which had zinc in it, and a possibility that this was causing her copper deficiency was raised. Serum zinc levels were normal, but urinary zinc was very high. The patient was advised to use zinc-free dental adhesive and her copper level returned to normal within a few months with normalisation of her pancytopaenia, and partial resolution of her oral paraesthesia. PMID:26452740

Physiological serum copper concentrations found in malignancies cause unfolding induced aggregation of human serum albumin in vitro.

PubMed

Rizvi, Asim; Furkan, Mohd; Naseem, Imrana

2017-12-15

Malignancies are characterized by several drastic metabolic changes, one of which is a progressive rise in the levels of serum copper. This rise in serum copper is documented across all malignancies and across malignancies in several species. This study aims to explore in vitro the effect of increased copper levels on the structure of the blood protein human serum albumin. Exposure of human serum albumin to physiologically relevant copper concentrations for 21 days resulted in structural modifications in the protein which were evident by changes in the intrinsic florescence. A loss of the predominantly alpha helical structure of human serum albumin was recorded along with a tendency to form protein aggregates. This aggregation was characterized by Thioflavin T and Congo Red assays. Rayleigh light scattering and turbidity assays confirmed aggregation. The aggregates were visually confirmed using transmission electron microscopy. This is the first report implicating increased copper levels as a cause of aggregation of blood proteins in malignancies. The physiological and biochemical implications of this phenomenon are discussed. Copyright © 2017. Published by Elsevier Inc.

Impact of Plumbing Age on Copper Levels in Drinking Water

EPA Science Inventory

Theory and limited practical experiences suggest that higher copper levels in drinking water tap samples are typically associated with newer plumbing systems, and levels decrease with increasing plumbing age. Past researchers have developed a conceptual model to explain the “agin...

Spectroscopy of Cu(II)-PcoC and the multicopper oxidase function of PcoA, two essential components of Escherichia coli pco copper resistance operon.

PubMed

Huffman, David L; Huyett, Jennifer; Outten, F Wayne; Doan, Peter E; Finney, Lydia A; Hoffman, Brian M; O'Halloran, Thomas V

2002-08-06

The plasmid-encoded pco copper resistance operon in Escherichia coli consists of seven genes that are expressed from two pco promoters in response to elevated copper; however, little is known about how they mediate resistance to excess environmental copper. Two of the genes encode the soluble periplasmic proteins PcoA and PcoC. We show here that inactivation of PcoC, and PcoA to a lesser extent, causes cells to become more sensitive to copper than wild-type nonresistant strains, consistent with a tightly coupled detoxification pathway. Periplasmic extracts show copper-inducible oxidase activity, attributed to the multicopper oxidase function of PcoA. PcoC, a much smaller protein than PcoA, binds one Cu(II) and exhibits a weak electronic transition characteristic of a type II copper center. ENDOR and ESEEM spectroscopy of Cu(II)-PcoC and the (15)N- and Met-CD(3)-labeled samples are consistent with a tetragonal ligand environment of three nitrogens and one aqua ligand "in the plane". A weakly associated S-Met and aqua are likely axial ligands. At least one N is a histidine and is likely trans to the in-plane aqua ligand. The copper chemistry of PcoC and the oxidase function of PcoA are consistent with the emerging picture of the chromosomally encoded copper homeostasis apparatus in the E. coli cell envelope [Outten, F. W., Huffman, D. L., Hale, J. A., and O'Halloran, T. V. (2001) J. Biol. Chem. 276, 30670-30677]. We propose a model for the plasmid system in which Cu(I)-PcoC functions in this copper efflux pathway as a periplasmic copper binding protein that docks with the multiple repeats of Met-rich domains in PcoA to effect oxidation of Cu(I) to the less toxic Cu(II) form. The solvent accessibility of the Cu(II) in PcoC may allow for metal transfer to other plasmid and chromosomal factors and thus facilitate removal of Cu(II) from the cell envelope.

Copper and ceruloplasmin dyshomeostasis in serum and cerebrospinal fluid of multiple sclerosis subjects.

PubMed

De Riccardis, L; Buccolieri, A; Muci, M; Pitotti, E; De Robertis, F; Trianni, G; Manno, D; Maffia, M

2018-05-01

Although many studies have been carried out in order to understand the implication of copper (Cu) in the pathogenesis of multiple sclerosis (MS), the exact role that this metal plays in the disease is not still clear. Because of the lack of information in this subject, the present study compared the serum and cerebrospinal (CSF) levels of copper in MS patients in respect to a control group, matched for age and sex, finding a significant increase of metal concentrations, in both biological fluids of MS subjects. To confirm the possible impairment of Cu metabolism, we analyzed ceruloplasmin (Cp) level and activity, seeing as this protein is an established peripheral marker in diseases associated with Cu imbalance. By comparing these two parameters between control and MS subjects, we found an increase of Cp levels, associated with a decrease in Cp activity, in the second group. By analysing these data, free copper levels were calculated, significantly increased in serum of MS subjects; the increase in free copper could be one of the predisposing factors responsible for the Cu altered levels in CSF of MS patients. At the same time, this alteration could be attributable to the inability to incorporate Cu by Cp, probably due to the high oxidative environment found in serum of MS patients. Overall, all these copper alterations may play a role in MS pathogenesis. Copyright © 2018 Elsevier B.V. All rights reserved.

Characterization and Low-Cost Remediation of Soils Contaminated by Timbers in Community Gardens.

PubMed

Heiger-Bernays, W; Fraser, A; Burns, V; Diskin, K; Pierotti, D; Merchant-Borna, K; McClean, M; Brabander, D; Hynes, H P

2009-01-01

Urban community gardens worldwide provide significant health benefits to those gardening and consuming fresh produce from them. Urban gardens are most often placed in locations and on land in which soil contaminants reflect past practices and often contain elevated levels of metals and organic contaminants. Garden plot dividers made from either railroad ties or chromated copper arsenate (CCA) pressure treated lumber contribute to the soil contamination and provide a continuous source of contaminants. Elevated levels of polycyclic aromatic hydrocarbons (PAHs) derived from railroad ties and arsenic from CCA pressure treated lumber are present in the gardens studied. Using a representative garden, we 1) determined the nature and extent of urban community garden soil contaminated with PAHs and arsenic by garden timbers; 2) designed a remediation plan, based on our sampling results, with our community partner guided by public health criteria, local regulation, affordability, and replicability; 3) determined the safety and advisability of adding city compost to Boston community gardens as a soil amendment; and 4) made recommendations for community gardeners regarding healthful gardening practices. This is the first study of its kind that looks at contaminants other than lead in urban garden soil and that evaluates the effect on select soil contaminants of adding city compost to community garden soil.

An urgent need to reassess the safe levels of copper in the drinking water: lessons from studies on healthy animals harboring no genetic deficits.

PubMed

Pal, Amit; Jayamani, Jayagandan; Prasad, Rajendra

2014-09-01

Recent seminal studies have established neurodegeneration, cognitive waning and/or β-amyloid deposition due to chronic copper intoxication via drinking water in healthy animals; henceforth, fuelling the debate all again over the safe levels of copper in the drinking water. This review encompasses the contemporary imperative animal studies in which the effect of chronic copper toxicity (especially via drinking water) was evaluated on the central nervous system and memory of uncompromised animals along with discussing the future perspectives. Copyright © 2014 Elsevier Inc. All rights reserved.

The Impact of Water Quality, Corrosion Inhibitors and Plumbing Age on Copper Release in Distribution Systems

EPA Science Inventory

The U.S. Environmental Protection Agency promulgated the Lead and Copper Rule (LCR) in 1991, which established a copper action level of 1.3 mg/L in the consumers’ tap water. As a result, researchers have examined the effects of water chemistry on the solubility of copper to esta...

Evaluating the Mechanism of Oxalate Synthesis of Fibroporia Radiculosa Isolates Adapting to Copper-Tolerance

Treesearch

Katie Marie Jenkins

2012-01-01

Despite the drawbacks associated with tolerant organisms, copper is still used as the key component in current wood preservatives. Copper-tolerant fungi, like Fibroporia radiculosa, produce and accumulate high levels of oxalate in response to copper. The biosynthesis of oxalate has been connected to specific enzymes in the glyoxylate and...

Effect of intradermal human recombinant copper-zinc superoxide dismutase on random pattern flaps in rats.

PubMed

Schein, Ophir; Westreich, Melvyn; Shalom, Avshalom

2013-09-01

Studies have focused on enhancing flap viability using superoxide dismutase (SOD), but only a few used SOD from human origin, and most gave the compound systemically. We evaluated the ability of SOD to improve random skin flap survival using human recombinant copper-zinc superoxide dismutase (Hr-CuZnSOD) in variable doses, injected intradermally into the flap. Seventy male Sprague Dawley rats were randomly assigned into 4 groups. Cephalic random pattern flaps were elevated on their backs and intradermal injections of different dosages of Hr-CuZnSOD were given 15 minutes before surgery. Flap survival was evaluated by fluorescein fluorescence. Analysis of variance (ANOVA) and t test statistical analyses were performed. Flap survival in all treated groups was significantly better than in the controls. The beneficial effect of HR-CuZnSOD on flap survival is attained when it is given intradermally into the flap tissue. Theoretically, Hr-CuZnSOD delivered with local anesthetics used in flap elevation may be a valuable clinical tool. Copyright © 2012 Wiley Periodicals, Inc.

Copper toxicology, oxidative stress and inflammation using zebrafish as experimental model.

PubMed

Pereira, Talita Carneiro Brandão; Campos, Maria Martha; Bogo, Maurício Reis

2016-07-01

Copper is an essential micronutrient and a key catalytic cofactor in a wide range of enzymes. As a trace element, copper levels are tightly regulated and both its deficit and excess are deleterious to the organism. Under inflammatory conditions, serum copper levels are increased and trigger oxidative stress responses that activate inflammatory responses. Interestingly, copper dyshomeostasis, oxidative stress and inflammation are commonly present in several chronic diseases. Copper exposure can be easily modeled in zebrafish; a consolidated model in toxicology with increasing interest in immunity-related research. As a result of developmental, economical and genetic advantages, this freshwater teleost is uniquely suitable for chemical and genetic large-scale screenings, representing a powerful experimental tool for a whole-organism approach, mechanistic studies, disease modeling and beyond. Copper toxicological and more recently pro-inflammatory effects have been investigated in both larval and adult zebrafish with breakthrough findings. Here, we provide an overview of copper metabolism in health and disease and its effects on oxidative stress and inflammation responses in zebrafish models. Copper-induced inflammation is highlighted owing to its potential to easily mimic pro-oxidative and pro-inflammatory features that combined with zebrafish genetic tractability could help further in the understanding of copper metabolism, inflammatory responses and related diseases. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Modulation of cholesterol levels in broiler meat by dietary garlic and copper.

PubMed

Konjufca, V H; Pesti, G M; Bakalli, R I

1997-09-01

Male Ross x Ross 208 chickens were fed from hatching to 21 d of age either a control diet (based on corn and soybean meal) or the control diet supplemented with 0, 1.5, 3.0, and 4.5% of a commercial garlic powder in Experiments 1 and 2. Once the dose-response relationship was established, 3% garlic powder or 63 or 180 mg/kg copper as cupric citrate or cupric sulfate pentahydrate were supplemented to the diet (Experiments 3, 4, 5, and 6). In the first two experiments, reductions of plasma cholesterol (P = 0.006) and triacylglycerols (P = 0.013) and liver (P = 0.012) and breast muscle (P = 0.165) cholesterol were observed in garlic-supplemented birds. Feeding either garlic powder or copper (63 and 180 mg/kg) resulted in reduced levels of plasma cholesterol, liver cholesterol, blood reduced glutathione, and breast and thigh muscle cholesterol. Differences were significant at P < 0.05 in at least one experiment. 3-Hydroxy-3-methylglutaryl reductase activity was decreased due to dietary garlic (P = 0.0369), but not by pharmacological levels of dietary copper (P = 0.982). The activity of fatty acid synthetase was decreased in birds fed copper (P = 0.035). Both garlic and copper supplements decreased cholesterol 7 alpha-hydroxylase activity (P = 0.024 and P = 0.022, respectively). The results of these trials confirm the findings that garlic and copper alter lipid and cholesterol metabolism. However, they do not work by the same mechanism. Feeding dietary garlic or copper for 21 d reduced cholesterol levels of broiler meat without altering growth of the chickens or feed efficiency.

Deficient copper concentrations in dried-defatted hepatic tissue from ob/ob mice: A potential model for study of defective copper regulation in metabolic liver disease.

PubMed

Church, Stephanie J; Begley, Paul; Kureishy, Nina; McHarg, Selina; Bishop, Paul N; Bechtold, David A; Unwin, Richard D; Cooper, Garth J S

2015-05-08

Ob/ob mice provide an animal model for non-alcoholic fatty liver disease/non-alcoholic steatohepatitis (NAFLD/NASH) in patients with obesity and type-2 diabetes. Low liver copper has been linked to hepatic lipid build-up (steatosis) in animals with systemic copper deficiency caused by low-copper diets. However, hepatic copper status in patients with NAFLD or NASH is uncertain, and a validated animal model useful for the study of hepatic copper regulation in common forms of metabolic liver disease is lacking. Here, we report parallel measurements of essential metal levels in whole-liver tissue and defatted-dried liver tissue from ob/ob and non-obese control mice. Measurements in whole-liver tissue from ob/ob mice at an age when they have developed NAFLD/NASH, provide compelling evidence for factitious lowering of copper and all other essential metals by steatosis, and so cannot be used to study hepatic metal regulation in this model. By marked contrast, metal measurements in defatted-dried liver samples reveal that most essential metals were actually normal and indicate specific lowering of copper in ob/ob mice, consistent with hepatic copper deficiency. Thus ob/ob mice can provide a model useful for the study of copper regulation in NAFLD and NASH, provided levels are measured in defatted-dried liver tissue. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Copper/MYC/CTR1 interplay: a dangerous relationship in hepatocellular carcinoma.

PubMed

Porcu, Cristiana; Antonucci, Laura; Barbaro, Barbara; Illi, Barbara; Nasi, Sergio; Martini, Maurizio; Licata, Anna; Miele, Luca; Grieco, Antonio; Balsano, Clara

2018-02-06

Free serum copper correlates with tumor incidence and progression of human cancers, including hepatocellular carcinoma (HCC). Copper extracellular uptake is provided by the transporter CTR1, whose expression is regulated to avoid excessive intracellular copper entry. Inadequate copper serum concentration is involved in the pathogenesis of Non Alcoholic Fatty Liver Disease (NAFLD), which is becoming a major cause of liver damage progression and HCC incidence. Finally, MYC is over-expressed in most of HCCs and is a critical regulator of cellular growth, tumor invasion and metastasis. The purpose of our study was to understand if higher serum copper concentrations might be involved in the progression of NAFLD-cirrhosis toward-HCC. We investigated whether high exogenous copper levels sensitize liver cells to transformation and if it exists an interplay between copper-related proteins and MYC oncogene. NAFLD-cirrhotic patients were characterized by a statistical significant enhancement of serum copper levels, even more evident in HCC patients. We demonstrated that high extracellular copper concentrations increase cell growth, migration, and invasion of liver cancer cells by modulating MYC/CTR1 axis. We highlighted that MYC binds a specific region of the CTR1 promoter, regulating its transcription. Accordingly, CTR1 and MYC proteins expression were progressively up-regulated in liver tissues from NAFLD-cirrhotic to HCC patients. This work provides novel insights on the molecular mechanisms by which copper may favor the progression from cirrhosis to cancer. The Cu/MYC/CTR1 interplay opens a window to refine HCC diagnosis and design new combined therapies.

Altered serum copper homeostasis suggests higher oxidative stress and lower antioxidant capability in patients with chronic hepatitis B.

PubMed

Huang, Yansong; Zhang, Yuan; Lin, Zhexuan; Han, Ming; Cheng, Hongqiu

2018-06-01

Copper homeostasis can be altered by inflammation. This study aimed to investigate the alteration of serum copper homeostasis and to explore its clinical significance in patients with chronic hepatitis B (CHB).Thirty-two patients with CHB and 10 aged- and sex-matched healthy controls were recruited. Analyses included serum levels of total copper (TCu), copper ions (Cu), small molecule copper (SMC), ceruloplasmin (CP), Cu/Zn superoxide dismutase 1 (SOD1), urinary copper, and the activities of serum CP and SOD1.The serum TCu and urinary copper levels in patients with CHB were significantly higher than the controls (P = .04 and .003), while the serum Cu was lower than the controls (P = .0002). CP and SOD1 activities in the serum were significantly lower in patients with CHB compared to controls (P = .005) despite higher serum concentrations. In addition, serum alanine aminotransferase inversely correlated with serum CP activity (P = .0318, r = -0.4065).Serum copper homeostasis was altered in this cohort of patients with CHB. The results suggest increased oxidative stress and impaired antioxidant capability in patients with CHB, in addition to necroinflammation. These results may provide novel insights into the diagnosis and treatment of patients with CHB.

Transportation and Bioavailability of Copper and Zinc in a Storm Water Retention Pond

NASA Astrophysics Data System (ADS)

Camponelli, K.; Casey, R. E.; Wright, M. E.; Lev, S. M.; Landa, E. R.

2006-05-01

Highway runoff has been identified as a non-point source of metals to storm water retention ponds. Zinc and copper are major components of tires and brake pads, respectively. As these automobile parts degrade, they deposit particulates onto the roadway surface. During a storm event, these metal containing particulates are washed into a storm water retention pond where they can then accumulate over time. These metals may be available to organisms inhabiting the pond and surrounding areas. This study focuses on tracking the metals from their deposition on the roadway to their transport and accumulation into a retention pond. The retention pond is located in Owings Mills, MD and collects runoff from an adjacent four lane highway. Pond sediments, background soils, road dust samples, and storm events were collected and analyzed. Copper and zinc concentrations in the pond sediments are higher than local background soils indicating that the pond is storing anthropogenically derived metals. Storm event samples also reveal elevated levels of copper and zinc transported through runoff, along with a large concentration of total suspended solids. After looking at the particulate and dissolved fractions of both metals in the runoff, the majority of the Zn and Cu are in the particulate fraction. Changes in TSS are proportional with changes in particulate bound Zn, indicating that the solid particulates that are entering into the pond are a major contributor of the total metal loading. Sequential extractions carried out on the road dust show that the majority of zinc is extracted in the second and third fractions and could become available to organisms in the pond. There is a small amount of Cu that is being released in the more available stages of the procedure; however the bulk of the Cu is seen in the more recalcitrant steps. In the pond sediments however, both Cu and Zn are only being released from the sediments in the later steps and are most likely not highly available.

Nutritional and Metabolic Biomarkers in Autism Spectrum Disorders: An Exploratory Study.

PubMed

Esparham, Anna E; Smith, Teri; Belmont, John M; Haden, Michael; Wagner, Leigh E; Evans, Randall G; Drisko, Jeanne A

2015-04-01

Autism spectrum disorder (ASD) is currently on the rise, now affecting approximately 1 in 68 children in the United States according to a 2010 surveillance summary from the Centers for Disease Control and Prevention (CDC). This figure is an estimated increase of 78% from the figure in 2002. The CDC suggests that more investigation is needed to understand this astounding increase in autism in such a short period. The aim of this pilot study was to determine whether a group of children with ASD exhibited similar variations in a broad array of potential correlates, including medical histories, symptoms, genetics, and multiple nutritional and metabolic biomarkers. This study was a retrospective, descriptive chart review. The study took place at the University of Kansas Medical Center (KUMC). Participants were 7 children with ASD who had sought treatment at the Integrative Medicine Clinic at the medical center. A majority of the children exhibited an elevated copper:zinc ratio and abnormal vitamin D levels. Children also demonstrated abnormal levels of the essential fatty acids: (1) α-linolenic acid (ALA)- C13:3W3, and (2) linoleic acid (LA)-C18:2W6; high levels of docosahexaenoic acid (DHA); and an elevated ω-6:ω-3 ratio. Three of 7 children demonstrated abnormal manganese levels. Children did not demonstrate elevated urine pyruvate or lactate but did have abnormal detoxification markers. Three of 7 patients demonstrated abnormalities in citric acid metabolites, bacterial metabolism, and fatty acid oxidation markers. A majority demonstrated elevated serum immunoglobulin G (IgG) antibodies to casein, egg whites, egg yolks, and peanuts. A majority had absent glutathione S-transferase (GSTM) at the 1p13.3 location, and 3 of 7 children were heterozygous for the glutathione S-transferase I105V (GSTP1). A majority also exhibited genetic polymorphism of the mitochondrial gene superoxide dismutase A16V (SOD2). The findings from this small group of children with ASD points to the existence of nutritional, metabolic, and genetic correlates of ASD. These factors appear to be important potential abnormalities that warrant a case control study to evaluate their reliability and validity as markers of ASD.

Characterization of the yeast copper-inducible promoter system in Arabidopsis thaliana

NASA Technical Reports Server (NTRS)

Granger, C. L.; Cyr, R. J.

2001-01-01

Inducible promoters or gene-switches are used to both spatially and temporally regulate gene expression. Such regulation can provide information concerning the function of a gene in a developmental context as well as avoid potential harmful effects due to overexpression. A gfp construct under the control of a copper-inducible promoter was introduced into Arabidopsis thaliana (L.) Heynh. and the regulatory parameters of this inducible promoter were determined. Here, we describe the time-course of up- and down-regulation of GFP expression in response to copper level, the optimal regulatory levels of copper, and the tissue specificity of expression in three transgenic lines. We conclude that the copper-inducible promoter system may be useful in regulating the time and location of gene expression in A. thaliana.

Laser synthesis of a copper-single-walled carbon nanotube nanocomposite via molecular-level mixing and non-equilibrium solidification

NASA Astrophysics Data System (ADS)

Tu, Jay F.; Rajule, Nilesh; Molian, Pal; Liu, Yi

2016-12-01

A copper-single-walled carbon nanotube (Cu-SWCNT) metal nanocomposite could be an ideal material if it can substantially improve the strength of copper while preserving the metal’s excellent thermal and electrical properties. However, synthesis of such a nanocomposite is highly challenging, because copper and SWCNTs do not form intermetallic compounds and are insoluble; as a result, there are serious issues regarding wettability and fine dispersion of SWCNTs within the copper matrix. In this paper we present a novel wet process, called the laser surface implantation process (LSI), to synthesize Cu-SWCNT nanocomposites by mixing SWCNTs into molten copper. The LSI process includes drilling several microholes on a copper substrate, filling the microholes with SWCNTs suspended in solution, and melting the copper substrate to create a micro-well of molten copper. The molten copper advances radially outward to engulf the microholes with pre-deposited SWCNTs to form the Cu-SWCNT implant upon solidification. Rapid and non-equilibrium solidification is achieved due to copper’s excellent heat conductivity, so that SWCNTs are locked in position within the copper matrix without agglomerating into large clusters. This wet process is very different from the typical dry processes used in powder metallurgy. Very high hardness improvement, up to 527% over pure copper, was achieved, confirmed by micro-indentation tests, with only a 0.23% SWCNT volume fraction. The nanostructure of the nanocomposite was characterized by TEM imaging, energy-dispersive x-ray spectroscopy mapping and spectroscopy measurements. The SWCNTs were found to be finely dispersed within the copper matrix with cluster sizes in the range of nanometers, achieving the goal of molecular-level mixing.

Idiopathic hyperzincemia with associated copper deficiency anemia: a diagnostic dilemma.

PubMed

Merza, Hussein; Sood, Neha; Sood, Raman

2015-10-01

Prompt serum copper and zinc in addition to vitamin B12 levels should be measured in patients suffering from refractory anemia with neurological symptoms. A timely copper supplementation can help revert the hematological and possibly the neurological manifestations.

The association between low levels of lead in blood and occupational noise-induced hearing loss in steel workers.

PubMed

Hwang, Yaw-Huei; Chiang, Han-Yueh; Yen-Jean, Mei-Chu; Wang, Jung-Der

2009-12-15

As the use of leaded gasoline has ceased in the last decade, background lead exposure has generally been reduced. The aim of this study was to examine the effect of low-level lead exposure on human hearing loss. This study was conducted in a steel plant and 412 workers were recruited from all over the plant. Personal information such as demographics and work history was obtained through a questionnaire. All subjects took part in an audiometric examination of hearing thresholds, for both ears, with air-conducted pure tones at frequencies of 500, 1000, 2000, 3000, 4000, 6000 and 8000 Hz. Subjects' blood samples were collected and analyzed for levels of manganese, copper, zinc, arsenic, cadmium and lead with inductive couple plasma-mass spectrometry. Meanwhile, noise levels in different working zones were determined using a sound level meter with A-weighting network. Only subjects with hearing loss difference of no more than 15 dB between both ears and had no congenital abnormalities were included in further data analysis. Lead was the only metal in blood found significantly correlated with hearing loss for most tested sound frequencies (p<0.05 to p<0.0001). After adjustment for age and noise level, the logistic regression model analysis indicated that elevated blood lead over 7 microg/dL was significantly associated with hearing loss at the sound frequencies of 3000 through 8000 Hz with odds ratios raging from 3.06 to 6.26 (p<0.05-p<0.005). We concluded that elevated blood lead at level below 10 microg/dL might enhance the noise-induced hearing loss. Future research needs to further explore the detailed mechanism.

Response to copper and sodium chloride excess in Spirulina sp. (cyanobacteria).

PubMed

Deniz, F; Saygideger, S D; Karaman, S

2011-07-01

Physiological responses of the cyanobacterium, Spirulina sp., were evaluated following exposure to copper (0.1 and 1.0 mg/L) and sodium chloride (0.2 and 0.4 mol/L) for 7 days. Growth and chlorophyll a content exhibited decreases at most exposure levels, while increases occurred for malondialdehyde at all exposure levels. Proline content was increased at the higher exposure levels. Carotenoid levels of Spirulina sp. were not significantly changed. Increased amounts of malondialdehyde were indicative of free radical formation in Spirulina sp. under the stress, while increasing levels of proline pointed to the occurrence of a scavenging mechanism. Concentrations of copper in Spirulina sp. decreased with increasing concentrations of NaCl.

Prediction of Thermal Fatigue in Tooling for Die-casting Copper via Finite Element Analysis

NASA Astrophysics Data System (ADS)

Sakhuja, Amit; Brevick, Jerald R.

2004-06-01

Recent research by the Copper Development Association (CDA) has demonstrated the feasibility of die-casting electric motor rotors using copper. Electric motors using copper rotors are significantly more energy efficient relative to motors using aluminum rotors. However, one of the challenges in copper rotor die-casting is low tool life. Experiments have shown that the higher molten metal temperature of copper (1085 °C), as compared to aluminum (660 °C) accelerates the onset of thermal fatigue or heat checking in traditional H-13 tool steel. This happens primarily because the mechanical properties of H-13 tool steel decrease significantly above 650 °C. Potential approaches to mitigate the heat checking problem include: 1) identification of potential tool materials having better high temperature mechanical properties than H-13, and 2) reduction of the magnitude of cyclic thermal excursions experienced by the tooling by increasing the bulk die temperature. A preliminary assessment of alternative tool materials has led to the selection of nickel-based alloys Haynes 230 and Inconel 617 as potential candidates. These alloys were selected based on their elevated temperature physical and mechanical properties. Therefore, the overall objective of this research work was to predict the number of copper rotor die-casting cycles to the onset of heat checking (tool life) as a function of bulk die temperature (up to 650 °C) for Haynes 230 and Inconel 617 alloys. To achieve these goals, a 2D thermo-mechanical FEA was performed to evaluate strain ranges on selected die surfaces. The method of Universal Slopes (Strain Life Method) was then employed for thermal fatigue life predictions.

Time-dependent morphological and biochemical changes following cutaneous thermal burn injury and their modulation by copper nicotinate complex: an animal model.

PubMed

Nassar, Muammar A Y; Eldien, Heba M Saad; Tawab, Hanem S Abdel; Saleem, Tahia H; Omar, Hossam M; Nassar, Ahmed Y; Hussein, Mahmoud Rezk Abdelwahed

2012-10-01

Thermal tissue injury is partly mediated by reactive oxygen metabolites. Oxygen free radicals are contributory to local tissue damage following thermal injury and accordingly an interventional therapy using antioxidants may be beneficial. Copper nicotinate complex can scavenge reactive oxygen species (i.e., has antioxidant activity). To examine time-related morphological and biochemical changes following skin thermal injury and their modulation by copper nicotinate complex. An animal model composed of 80 albino rats was established. Ten rats (nonburn group) served as a control group. Seventy rats (burn group) were anesthetized, given a 10% total body surface area, full-thickness burn. Ten rats (from the postburn group) were sacrificed after 24 h (without treatment, i.e., untreated-burn group). The remaining rats were divided into three subgroups (20 rats, each) and were treated topically either with soft paraffin, moist exposed burn ointment (MEBO, a standard therapeutic treatment for burns), or copper nicotinate complex. Five animals from each subgroup were sacrificed every week over a period of 4 weeks. The morphological and biochemical changes were evaluated and compared among the different groups. High levels of the plasma and skin nitiric oxide (marker of oxidative stress) were observed in the untreated-burn group. These levels were significantly low following the application of copper nicotinate complex. Low levels of plasma and skin superoxide dismutase (marker of oxidative stress) and plasma ceruloplasmin were observed in the untreated-burn group. These levels were significantly high following copper nicotinate complex treatment. The total and differential leukocyte counts were low following the onset of the thermal injury. They gradually returned to normal levels over a 4-week period following the application of MEBO or copper nicotinate complex. Compared to untreated-burn group, postburn-healing changes (resolution of the inflammatory reaction, reepithelization of the epidermis, angiogenesis, deposition of collagen fibers, and recovery of the subcellualr organelles) were significantly accelerated following the application of either MEBO or copper nicotinate complex. Application of copper nicotinate complex was associated with improved healing of the thermal burns of the skin. The underlying molecular changes underlying these effects await further investigations.

Effect of copper on the scope for growth of clams (Tapes philippinarum) from a farming area in the Northern Adriatic Sea.

PubMed

Munari, Cristina; Mistri, Michele

2007-09-01

Copper is currently the most common biocide in antifouling paints. Levels of this metal were measured in the water, particulate matter and sediments from a shellfish farming area in the Sacca di Goro (Northern Adriatic Sea) over one year. With respect to the 1980s, copper environmental level increased twofold. The release of copper from shellfish farmers' boats was also estimated to be > 250 kg Cu y(-1). Clams Tapes philippinarum were collected in the same area and seasonally exposed to a sublethal (10 microg Cu l(-1)) concentration of copper. Physiological traits were significantly affected by copper exposure (scope for growth declined as a result of reduced clearance rate, increased oxygen consumption and a generally lower absorption efficiency). The results of this study are cause for concern for shellfish farming activities at least in Northern Adriatic, where shellfish farming is a monoculture of T. philippinarum. A strict interpretation of the precautionary principle might suggest that more rigorous regulatory action to control copper inputs in the field would be justified.

"Bulk" Nanocrystalline Metals: Review of the Current State of the Art and Future Opportunities for Copper and Copper Alloys

NASA Astrophysics Data System (ADS)

Tschopp, M. A.; Murdoch, H. A.; Kecskes, L. J.; Darling, K. A.

2014-06-01

It is a new beginning for innovative fundamental and applied science in nanocrystalline materials. Many of the processing and consolidation challenges that have haunted nanocrystalline materials are now more fully understood, opening the doors for bulk nanocrystalline materials and parts to be produced. While challenges remain, recent advances in experimental, computational, and theoretical capability have allowed for bulk specimens that have heretofore been pursued only on a limited basis. This article discusses the methodology for synthesis and consolidation of bulk nanocrystalline materials using mechanical alloying, the alloy development and synthesis process for stabilizing these materials at elevated temperatures, and the physical and mechanical properties of nanocrystalline materials with a focus throughout on nanocrystalline copper and a nanocrystalline Cu-Ta system, consolidated via equal channel angular extrusion, with properties rivaling that of nanocrystalline pure Ta. Moreover, modeling and simulation approaches as well as experimental results for grain growth, grain boundary processes, and deformation mechanisms in nanocrystalline copper are briefly reviewed and discussed. Integrating experiments and computational materials science for synthesizing bulk nanocrystalline materials can bring about the next generation of ultrahigh strength materials for defense and energy applications.

Effects of Copper Pollution on the Phenolic Compound Content, Color, and Antioxidant Activity of Wine.

PubMed

Sun, Xiangyu; Ma, Tingting; Han, Luyang; Huang, Weidong; Zhan, Jicheng

2017-05-03

The effects of copper pollution on the polyphenol content, color, and antioxidant activity of wine, as well as correlations among these factors, were investigated. Copper had clear influences on wine polyphenol content. At low copper concentrations, the concentrations of nearly all polyphenols increased, and the antioxidant activity values of the wine also increased. When the copper concentration reached the lowest level of the medium copper range (9.6~16 mg/L), most of the indices also improved. When the copper concentrations reached the latter part of the medium copper range (19.2 and 22.4 mg/L), many of the tested indices began to decrease. Furthermore, when the copper concentration reached the high ranges (32, 64, and 96 mg/L), the polyphenol content, CIELAB color parameters, and antioxidant activity of wine were substantially decreased, indicating the need to control increasing copper content in grape must.

Gastrointestinal upsets associated with ingestion of copper-contaminated water.

PubMed Central

Knobeloch, L; Ziarnik, M; Howard, J; Theis, B; Farmer, D; Anderson, H; Proctor, M

1994-01-01

During 1992 and 1993 the Wisconsin Division of Health investigated five cases in which copper-contaminated drinking water was suspected of causing gastrointestinal upsets. Each of these case studies was conducted after our office was notified of high copper levels in drinking water or notified of unexplained illnesses. Our findings suggest that drinking water that contains copper at levels above the federal action limit of 1.3 mg/l may be a relatively common cause of diarrhea, abdominal cramps, and nausea. These symptoms occurred most frequently in infants and young children and among resident of newly constructed or renovated homes. Images p958-a PMID:9738210

Responses of hybrid striped bass to waterborne and dietary copper in freshwater and saltwater

USGS Publications Warehouse

Bielmyer, G.K.; Gatlin, D.; Isely, J.J.; Tomasso, J.; Klaine, S.J.

2005-01-01

Mechanisms of copper toxicity and consequences of exposure vary due to uptake route and ionoregulatory status. The goal of this research was to develop a model fish system to assess the influence of different Cu exposure routes (waterborne or dietary) on bioavailability, uptake, and effects in hybrid striped bass (Morone chrysops×Morone saxatilis) acclimated to fresh- or saltwater. Initially, hybrid striped bass were exposed to dietary Cu concentrations of 571, 785, and 1013 μg Cu/g, along with a control (∼ 5 μg Cu/g), for 14 days in saltwater. Intestinal and liver Cu accumulated in a dose-dependent manner in fish exposed to increasing levels of dietary Cu. Chronic (42 days) experiments were then conducted to determine sub-lethal effects of aqueous, dietary, and combined aqueous and dietary Cu exposures to both freshwater- and saltwater-acclimated hybrid striped bass. Growth and Cu accumulation in the gill, intestine, and liver were measured. Although no significant effects were observed in fish exposed to waterborne Cu, those exposed through the diet accumulated significant liver and intestinal Cu but showed no significant change in growth. Overall, these results suggest that at the levels tested, exposure to elevated waterborne Cu did not cause significant long-term tissue Cu accumulation, whereas dietary Cu exposure caused significant liver and intestinal Cu accumulation in hybrid striped bass which was comparable in both freshwater and saltwater (15 g/L).

Differential expression of acid invertase genes in roots of metallicolous and non-metallicolous populations of Rumex japonicus under copper stress.

PubMed

Huang, Wu-Xing; Cao, Yi; Huang, Li-Juan; Ren, Cong; Xiong, Zhi-Ting

2011-09-01

Recent evidence indicates that during copper (Cu) stress, the roots of metallicolous plants manifest a higher activity of acid invertase enzymes, which are rate-limiting in sucrose catabolism, than non-metallicolous plants. To test whether the higher activity of acid invertases is the result of higher expression of acid invertase genes, we isolated partial cDNAs for acid invertases from two populations of Rumex japonicus (from metalliferous and non-metalliferous soils), determined their nucleotide sequences, and designed primers to measure changes in transcript levels during Cu stress. We also determined the growth of the plants' roots, Cu accumulation, and acid invertase activities. The seedlings of R. japonicus were exposed to control or 20 μM Cu(2+) for 6d under hydroponic conditions. The transcript level and enzyme activity of acid invertases in metallicolous plants were both significantly higher than those in non-metallicolous plants when treated with 20 μM. Under Cu stress, the root length and root biomass of metallicolous plants were also significantly higher than those of non-metallicolous plants. The results suggested that under Cu stress, the expression of acid invertase genes in metallicolous plants of R. japonicus differed from those in non-metallicolous plants. Furthermore, the higher acid invertase activities of metallicolous plants under Cu stress could be due in part to elevated expression of acid invertase genes. Copyright © 2011 Elsevier Ltd. All rights reserved.

Soy isoflavone supplementation elevates erythrocyte superoxide dismutase, but not plasma ceruloplasmin in postmenopausal breast cancer survivors.

PubMed

DiSilvestro, Robert A; Goodman, Jaime; Dy, Emily; Lavalle, Gregory

2005-02-01

Soy isoflavone antioxidant effects may help prevent breast cancer re-occurrence, but isoflavone estrogen-like actions may increase breast cancer risk. These isoflavone actions can be reflected by effects on two copper enzymes activities, superoxide dismutase 1 (SOD 1), which has antioxidant function relevant to breast cancer prevention, and ceruloplasmin, which has its synthesis up-regulated by estrogen, and for which high values are associated with high breast cancer risk. A soy isoflavone-rich concentrate supplement was examined for effects on these two copper enzyme activities in post-menopausal breast cancer survivors (n = 7) in a crossover design with a placebo (24 days on supplement or placebo; 14 day wash out). The soy concentrate, but not the placebo, increased erythrocyte SOD 1 activities, but not ceruloplasmin activities or protein. The effect on superoxide dismutase activities was not likely due to increased copper intake since analysis of the soy extract showed little copper. The effect on superoxide dismutase was not accompanied by a change in urinary contents of 8-deoxyhydroxyguanosine, a DNA oxidant product, though perhaps this would change with a longer intervention. In summary, in regard to two copper enzyme activities, an isoflavone-rich soy concentrate showed an antioxidant effect considered relevant to breast cancer, but not an effect associated with estrogenic activity and increased breast cancer risk.

The association between serum copper concentrations and cardiovascular disease risk factors in children and adolescents in NHANES.

PubMed

Zang, Xiaodong; Huang, Hesuyuan; Zhuang, Zhulun; Chen, Runsen; Xie, Zongyun; Xu, Cheng; Mo, Xuming

2018-06-01

Copper is an essential element in human beings, alterations in serum copper levels could potentially have effect on human health. To date, no data are available regarding how serum copper affects cardiovascular disease (CVD) risk factors in children and adolescents. We examined the association between serum copper levels and CVD risk factors in children and adolescents. We analyzed data consisting of 1427 subjects from a nationally representative sample of the US population in the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2014. The CVD risk factors included total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, fasting glucose, glycohemoglobin, fasting insulin, and blood pressure. Multivariate and generalized linear regressions were performed to investigate associations adjusted for age, gender, ethnicity, poverty:income ratio (PIR), BMI, energy intake, and physical activity. We found significant associations between serum copper and total cholesterol (coefficient = 0.132; 95% CI 0.081, 0.182; P for trend < 0.001), glycohemoglobin (coefficient = 0.044; 95% CI 0.020, 0.069; P < 0.001), and fasting insulin (coefficient = 0.730; 95% CI 0.410, 1.050; P < 0.001) among the included participants. Moreover, in the generalized linear models, subjects with the highest copper levels demonstrated a 0.83% (95% CI 0.44%, 1.24%) greater increase in serum total cholesterol (p for trend < 0.001) when compared to participants with the lowest copper concentrations. Our results provide the first epidemiological evidence that serum copper concentrations are associated with total cholesterol concentrations in children and adolescents. However, the underlying mechanisms still need further exploration.

ROS dependent copper toxicity in Hydra-biochemical and molecular study.

PubMed

Zeeshan, Mohammed; Murugadas, Anbazhagan; Ghaskadbi, Surendra; Rajendran, Ramasamy Babu; Akbarsha, Mohammad Abdulkader

2016-01-01

Copper, an essential microelement, is known to be toxic to aquatic life at concentrations higher than that could be tolerated. Copper-induced oxidative stress has been documented in vitro, yet the in vivo effects of metal-induced oxidative stress have not been extensively studied in the lower invertebrates. The objective of the present study has been to find the effect of ROS-mediated toxicity of environmentally relevant concentrations of copper at organismal and cellular levels in Hydra magnipapillata. Exposure to copper at sublethal concentrations (0.06 and 0.1mg/L) for 24 or 48h resulted in generation of significant levels of intracellular reactive oxygen species (ROS). We infer that the free radicals here originate predominantly at the lysosomes but partly at the mitochondria also as visualized by H2-DHCFDA staining. Quantitative real-time PCR of RNA extracted from copper-exposed polyps revealed dose-dependent up-regulation of all antioxidant response genes (CAT, SOD, GPx, GST, GR, G6PD). Concurrent increase of Hsp70 and FoxO genes suggests the ability of polyps to respond to stress, which at 48h was not the same as at 24h. Interestingly, the transcript levels of all genes were down-regulated at 48h as compared to 24h incubation period. Comet assay indicated copper as a powerful genotoxicant, and the DNA damage was dose- as well as duration-dependent. Western blotting of proteins (Bax, Bcl-2 and caspase-3) confirmed ROS-mediated mitochondrial cell death in copper-exposed animals. These changes correlated well with changes in morphology, regeneration and aspects of reproduction. Taken together, the results indicate increased production of intracellular ROS in Hydra on copper exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

Molecular Basis for Antioxidant Enzymes in Mediating Copper Detoxification in the Nematode Caenorhabditis elegans

PubMed Central

Song, Shaojuan; Zhang, Xueyao; Wu, Haihua; Han, Yan; Zhang, Jianzhen; Ma, Enbo; Guo, Yaping

2014-01-01

Antioxidant enzymes play a major role in defending against oxidative damage by copper. However, few studies have been performed to determine which antioxidant enzymes respond to and are necessary for copper detoxification. In this study, we examined both the activities and mRNA levels of SOD, CAT, and GPX under excessive copper stress in Caenorhabditis elegans, which is a powerful model for toxicity studies. Then, taking advantage of the genetics of this model, we assessed the lethal concentration (LC50) values of copper for related mutant strains. The results showed that the SOD, CAT, and GPX activities were significantly greater in treated groups than in controls. The mRNA levels of sod-3, sod-5, ctl-1, ctl-2, and almost all gpx genes were also significantly greater in treated groups than in controls. Among tested mutants, the sod-5, ctl-1, gpx-3, gpx-4, and gpx-6 variants exhibited hypersensitivity to copper. The strains with SOD or CAT over expression were reduced sensitive to copper. Mutations in daf-2 and age-1, which are involved in the insulin/insulin-like growth factor-1 signaling pathway, result in reduced sensitivity to stress. Here, we showed that LC50 values for copper in daf-2 and age-1 mutants were significantly greater than in N2 worms. However, the LC50 values in daf-16;daf-2 and daf-16;age-1 mutants were significantly reduced than in daf-2 and age-1 mutants, implying that reduced copper sensitivity is influenced by DAF-16-related functioning. SOD, CAT, and GPX activities and the mRNA levels of the associated copper responsive genes were significantly increased in daf-2 and age-1 mutants compared to N2. Additionally, the activities of SOD, CAT, and GPX were greater in these mutants than in N2 when treated with copper. Our results not only support the theory that antioxidant enzymes play an important role in copper detoxification but also identify the response and the genes involved in these processes. PMID:25243607

Colloidal and electrochemical aspects of copper-CMP

NASA Astrophysics Data System (ADS)

Sun, Yuxia

Copper based interconnects with low dielectric constant layers are currently used to increase interconnect densities and reduce interconnect time delays in integrated circuits. The technology used to develop copper interconnects involves Chemical Mechanical Planarization (CMP) of copper films deposited on low-k layers (silica or silica based films), which is carried out using slurries containing abrasive particles. One issue using such a structure is copper contamination over dielectric layers (SiO2 film), if not reduced, this contamination will cause current leakage. In this study, the conditions conducive to copper contamination onto SiO2 films during Cu-CMP process were studied, and a post-CMP cleaning technique was discussed based on experimental results. It was found that the adsorption of copper onto a silica surface is kinetically fast (<0.5 minute). The amount of copper absorbed is pH and concentration dependent and affected by presence of H2O2, complexing agents, and copper corrosion inhibitor Benzotrazole. Based on de-sorption results, DI water alone was unable to reduce adsorbed copper to an acceptable level, especially for adsorption that takes place at a higher pH condition. The addition of complex agent, citric acid, proved effective in suppressing copper adsorption onto oxide silica during polishing or post-CMP cleaning by forming stable copper-CA complexes. Surface Complexation Modeling was used to simulate copper adsorption isotherms and predict the copper contamination levels on SiO2 surfaces. Another issue with the application of copper CMP is its environmental impact. CMP is a costly process due to its huge consumption of pure water and slurry. Additionally, Cu-CMP processing generates a waste stream containing certain amounts of copper and abrasive slurry particles. In this study, the separation technique electrocoagulation was investigated to remove both copper and abrasive slurry particles simultaneously. For effluent containing ˜40 ppm dissolved copper, it was found that ˜90% dissolved copper was removed from the waste streams through electroplating and in-situ chemical precipitation. The amount of copper removed through plating is impacted by membrane surface charge, type/amount of complexing agents, and solid content in the slurry suspension. The slurry particles can be removed ˜90% within 2 hours of EC through multiple mechanisms.

Mercury contribution to an Adirondack lake

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scrudato, R.J.; Long, D.; Weinbloom, R.

1987-01-01

Elevated copper, lead, and zinc concentrations in the upper 10 to 20 cm of sediment sampled from Cranberry Lake, a large Adirondack lake, are attributed to atmospheric contributions. Pb-210 and pollen core data, however, suggest Cranberry Lake also received mercury discharges during the turn of the century when the area was the center of extensive lumbering and related activities. Elevated mercury concentrations in Cranberry Lake smallmouth bass derived from remobilization from mercury-contaminated bottom sediments which increased the bioavailability to Cranberry Lake organisms. Mercury remobilization and accumulation by fish are promoted by fluctuating pH values resulting from acid precipitation.

Mercury contribution to an adirondack lake

NASA Astrophysics Data System (ADS)

Scrudato, R. J.; Long, D.; Weinbloom, Robert

1987-10-01

Elevated copper, lead, and zinc concentrations in the upper 10 to 20 cm of sediment sampled from Cranberry Lake, a large Adirondack lake, are attributed to atmospheric contributions. Pb-210 and pollen core data, however, suggest Cranberry Lake also received mercury discharges during the turn of the century when the area was the center of extensive lumbering and related activities. Elevated mercury concentrations in Cranberry Lake smallmouth bass derived from remobilization from mercury-contaminated bottom sediments which increased the bioavailability to Cranberry Lake organisms. Mercury remobilization and accumulation by fish are promoted by fluctuating pH values resulting from acid precipilation.

Idiopathic hyperzincemia with associated copper deficiency anemia: a diagnostic dilemma

PubMed Central

Merza, Hussein; Sood, Neha; Sood, Raman

2015-01-01

Key Clinical Message Prompt serum copper and zinc in addition to vitamin B12 levels should be measured in patients suffering from refractory anemia with neurological symptoms. A timely copper supplementation can help revert the hematological and possibly the neurological manifestations. PMID:26509015

A LATENT PERIOD IN THE ACTION OF COPPER ON RESPIRATION

PubMed Central

Cook, S. F.

1926-01-01

1. When copper chloride is allowed to act on Aspergillus niger there is at first a period during which there is no change in the rate of the production of carbon dioxide, following which the rate of respiration falls. The interval of no change is called the latent period. 2. When the copper is removed from the external solution before the end of the latent period this interval is prolonged. The rate of respiration then falls to a new level below the normal level. 3. Experiments on Nitella and on Valonia indicate that the copper penetrates the cell almost immediately. 4. The length of the latent period varies inversely as a constant power of the concentration of the copper. 5. These results are explained by assuming that the copper is made active in the respiration system by means of a reversible reaction. By using appropriate velocity constants the experimental curves can be duplicated by calculated curves. PMID:19872281

Copper induces expression and methylation changes of early development genes in Crassostrea gigas embryos.

PubMed

Sussarellu, Rossana; Lebreton, Morgane; Rouxel, Julien; Akcha, Farida; Rivière, Guillaume

2018-03-01

Copper contamination is widespread along coastal areas and exerts adverse effects on marine organisms such as mollusks. In the Pacific oyster, copper induces severe developmental abnormalities during early life stages; however, the underlying molecular mechanisms are largely unknown. This study aims to better understand whether the embryotoxic effects of copper in Crassostrea gigas could be mediated by alterations in gene expression, and the putative role of DNA methylation, which is known to contribute to gene regulation in early embryo development. For that purpose, oyster embryos were exposed to 4 nominal copper concentrations (0.1, 1, 10 and 20 μg L -1 Cu 2+ ) during early development assays. Embryotoxicity was monitored through the oyster embryo-larval bioassay at the D-larva stage 24 h post fertilization (hpf) and genotoxicity at gastrulation 7 hpf. In parallel, the relative expression of 15 genes encoding putative homeotic, biomineralization and DNA methylation proteins was measured at three developmental stages (3 hpf morula stage, 7 hpf gastrula stage, 24 hpf D-larvae stage) using RT-qPCR. Global DNA content in methylcytosine and hydroxymethylcytosine were measured by HPLC and gene-specific DNA methylation levels were monitored using MeDIP-qPCR. A significant increase in larval abnormalities was observed from copper concentrations of 10 μg L -1 , while significant genotoxic effects were detected at 1 μg L -1 and above. All the selected genes presented a stage-dependent expression pattern, which was impaired for some homeobox and DNA methylation genes (Notochord, HOXA1, HOX2, Lox5, DNMT3b and CXXC-1) after copper exposure. While global DNA methylation (5-methylcytosine) at gastrula stage didn't show significant changes between experimental conditions, 5-hydroxymethylcytosine, its degradation product, decreased upon copper treatment. The DNA methylation of exons and the transcript levels were correlated in control samples for HOXA1 but such a correlation was diminished following copper exposure. The methylation level of some specific gene regions (HoxA1, Hox2, Engrailed2 and Notochord) displayed changes upon copper exposure. Such changes were gene and exon-specific and no obvious global trends could be identified. Our study suggests that the embryotoxic effects of copper in oysters could involve homeotic gene expression impairment possibly by changing DNA methylation levels. Copyright © 2018 Elsevier B.V. All rights reserved.

Copper/MYC/CTR1 interplay: a dangerous relationship in hepatocellular carcinoma

PubMed Central

Barbaro, Barbara; Illi, Barbara; Nasi, Sergio; Martini, Maurizio; Licata, Anna; Miele, Luca; Grieco, Antonio; Balsano, Clara

2018-01-01

Free serum copper correlates with tumor incidence and progression of human cancers, including hepatocellular carcinoma (HCC). Copper extracellular uptake is provided by the transporter CTR1, whose expression is regulated to avoid excessive intracellular copper entry. Inadequate copper serum concentration is involved in the pathogenesis of Non Alcoholic Fatty Liver Disease (NAFLD), which is becoming a major cause of liver damage progression and HCC incidence. Finally, MYC is over-expressed in most of HCCs and is a critical regulator of cellular growth, tumor invasion and metastasis. The purpose of our study was to understand if higher serum copper concentrations might be involved in the progression of NAFLD-cirrhosis toward-HCC. We investigated whether high exogenous copper levels sensitize liver cells to transformation and if it exists an interplay between copper-related proteins and MYC oncogene. NAFLD-cirrhotic patients were characterized by a statistical significant enhancement of serum copper levels, even more evident in HCC patients. We demonstrated that high extracellular copper concentrations increase cell growth, migration, and invasion of liver cancer cells by modulating MYC/CTR1 axis. We highlighted that MYC binds a specific region of the CTR1 promoter, regulating its transcription. Accordingly, CTR1 and MYC proteins expression were progressively up-regulated in liver tissues from NAFLD-cirrhotic to HCC patients. This work provides novel insights on the molecular mechanisms by which copper may favor the progression from cirrhosis to cancer. The Cu/MYC/CTR1 interplay opens a window to refine HCC diagnosis and design new combined therapies. PMID:29507693

Studies on the feeding of cupric sulfate pentahydrate, cupric citrate, and copper oxychloride to broiler chickens.

PubMed

Ewing, H P; Pesti, G M; Bakalli, R I; Menten, J F

1998-03-01

Male commercial broiler strain chickens were fed either a control diet (based on corn and soybean meal) or the control diet supplemented with cupric sulfate pentahydrate, copper oxychloride, or cupric citrate in two experiments conducted in floor pens. In Experiment 1, feeding copper at 125 mg/kg diet for 42 d significantly increased broiler growth; and the response from cupric citrate was significantly better than either cupric sulfate or copper oxychloride. In Experiment 2, the inclusion of copper from cupric citrate was reduced to 63 mg/kg and the length of the experiment was increased to 56 d. Cupric sulfate pentahydrate and copper oxychloride treatments increased weight gain by 4.9% and cupric citrate increased weight gain by 9.1%. The feed conversion ratios (grams of feed:grams of gain of live birds) in the birds fed copper were not significantly different from those fed the basal diet (P > 0.05) unless corrections were made for the weights of the dead birds; the adjusted feed conversion ratios (grams of feed:grams of gain of live birds + grams of gain of mortalities) for the copper-treated birds in Experiments 1 and 2 were 5.2 and 7.6% lower, respectively, than the ratios of birds fed the basal diets. Plasma copper levels increased in supplemented chicks by 35% in Experiment 1 and 24% in Experiment 2. Liver copper levels in both experiments were increased by 26% with copper supplementation. Mortality was not affected by dietary treatment in either experiment (P > 0.05).

In situ antimicrobial behavior of materials with copper-based additives in a hospital environment.

PubMed

Palza, Humberto; Nuñez, Mauricio; Bastías, Roberto; Delgado, Katherine

2018-06-01

Copper and its alloys are effective antimicrobial surface materials in the laboratory and in clinical trials. Copper has been used in the healthcare setting to reduce environmental contamination, and thus prevent healthcare-associated infections, complementing traditional protocols. The addition of copper nanoparticles to polymer/plastic matrices can also produce antimicrobial materials, as confirmed under laboratory conditions. However, there is a lack of studies validating the antimicrobial effects of these nanocomposite materials in clinical trials. To satisfy this issue, plastic waiting room chairs with embedded metal copper nanoparticles, and metal hospital IV pools coated with an organic paint with nanostructured zeolite/copper particles were produced and tested in a hospital environment. These prototypes were sampled once weekly for 10 weeks and the viable microorganisms were analysed and compared with the copper-free materials. In the waiting rooms, chairs with copper reduced by around 73% the total viable microorganisms present, showing activity regardless of the microorganism tested. Although there were only low levels of microorganisms in the IV pools installed in operating rooms because of rigorous hygiene protocols, samples with copper presented lower total viable microorganisms than unfilled materials. Some results did not have statistical significance because of the low load of microorganisms; however, during at least three weeks the IV pools with copper had reduced levels of microorganisms by a statistically significant 50%. These findings show for the first time the feasibility of utilizing the antimicrobial property of copper by adding nanosized fillers to other materials in a hospital environment. Copyright © 2018 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Transcuprein is a Macroglobulin Regulated by Copper and Iron Availability

PubMed Central

Liu, Nanmei; Lo, Louis Shi-li; Askary, S. Hassan; Jones, LaTrice; Kidane, Theodros Z.; Nguyen, Trisha Trang Minh; Goforth, Jeremy; Chu, Yu-Hsiang; Vivas, Esther; Tsai, Monta; Westbrook, Terence; Linder, Maria C.

2009-01-01

SUMMARY Transcuprein is a high affinity copper carrier in the plasma involved in the initial distribution of copper entering the blood from the digestive tract. To identify and obtain cDNA for this protein, it was purified from rat plasma by size exclusion and copper chelate affinity chromatography, and amino acid sequences were obtained. These revealed a 190 kDa glycosylated protein identified as the macroglobulin, α1inhibitorIII, the main macroglobulin of rodent blood plasma. Albumin (65 kDa) co-purified in variable amounts and was concluded to be a contaminant (although it transiently can bind the macroglobulin). The main macroglobulin in human blood plasma (α2-macroglobulin), homologous to α1inhibitorIII, also bound copper tightly. Expression of α1I3 (transcuprein) mRNA by the liver was examined in rats with and without copper deficiency, using quantitative PCR and Northern analysis. Protein expression was examined by Western blotting. Deficient rats with 40% less ceruloplasmin oxidase activity and liver copper concentrations expressed about twice as much α1I3 mRNA, but circulating levels of transcuprein did not differ. Iron deficiency, which increased liver copper concentrations 3-fold, reduced transcuprein mRNA expression and 7circulating levels of transcuprein relative to what occurred in rats with normal or excess iron. We conclude that transcupreins are specific macroglobulins that not only carry zinc but also transport copper in the blood; and that their expression can be modulated by copper and iron availability. PMID:17363239

Effects of copper on growth, metamorphosis and endocrine disruption of Bufo gargarizans larvae.

PubMed

Wang, Chao; Liang, Gang; Chai, Lihong; Wang, Hongyuan

2016-01-01

Chinese toad (Bufo gargarizans) tadpoles were exposed to copper (1, 6.4, 32 and 64μgL(-1) copper) from the beginning of larval period through completion of metamorphosis. We examined the effects of chronic copper exposure on mortality, growth, time to metamorphosis, tail resorption time, body size at the metamorphic climax (Gs 42) and completion of metamorphosis (Gs 46) and thyroid gland histology. In addition, type 2 and 3 iodothyronine deiodinase (Dio2 and Dio3), thyroid hormone receptors (TRα and TRβ) mRNA levels were also measured to assess disruption of TH synthesis. Our result showed that 6.4-64μgL(-1) copper concentration increased the mortality and inhibited the growth of B. gargarizans tadpoles. In addition, significant reduction in size at Gs 42 and a time delay to Gs 42 were observed at 6.4-64μgL(-1) copper treatments. Moreover, histological examinations have clearly revealed that 64μgL(-1) copper caused follicular cell hyperplasia in thyroid gland. According to real-time PCR results, exposure to 32 and 64μgL(-1) copper significantly up-regulated mRNA expression of Dio3, but down-regulated mRNA expression of TRα and TRβ mRNA level. We concluded that copper delayed amphibian metamorphosis through changing mRNA expression of Dio3, TRα and TRβ, which suggests that copper might have the endocrine-disrupting effect. Copyright © 2015 Elsevier B.V. All rights reserved.

Screening of Blood Levels of Mercury, Cadmium, and Copper in Pregnant Women in Dakahlia, Egypt: New Attention to an Old Problem.

PubMed

Motawei, Shimaa M; Gouda, Hossam E

2016-06-01

Heavy metals toxicity is a prevalent health problem particularly in developing countries. Mercury and cadmium are toxic elements that have no physiologic functions in human body. They should not be present in the human body by any concentration. Copper, on the other hand, is one of the elements that are essential for normal cell functions and a deficiency as well as an excess of which can cause adverse health effects. To test blood levels of mercury, cadmium, and copper in pregnant women in Dakahlia, Egypt. Using atomic absorption spectrophotometry, blood levels of cadmium, mercury, and copper were measured in 150 pregnant women attending to the antenatal care in Mansoura University Hospital in Dakahlia governorate, Egypt. The mean ± SD of blood mercury, cadmium, and copper levels were found to be far from their levels in the population surveys carried in developed countries like United States of America (USA) and Canada. Heavy metal intoxication and accumulation is a major health hazard. Developing countries, including Egypt, still lack many of the regulatory policies and legislations to control sources of pollution exposure. This should be dealt with in order to solve this problem and limit its health consequences.

[RESULTS OF DUST FACTOR IN COPPER PYROMETALLURGY].

PubMed

Adrianovskiy, V I; Lipatov, G Ya; Zebzeeva, N V; Kuzmina, E A

2016-01-01

The dust entering the air of the working zone of metallurgical shops was shown to be presented by a disintegration aerosols originating in crushing and transporting ore materials and condensation occurring in the course of smelting, converting and fire-refining copper. The overwhelming majority of the grains have a size of 2.1-5.0 mm, which determines a fixed condition of the presence of given dust in the working area, its long presence in the deeper parts of the respiratory system. At the preparatory stages in the composition of the dust there are presented significant amounts of crystalline silicon dioxide possessing of the fibrogenic impact on the body. In the dust the presence of the crystalline silicon dioxide, arsenic, nickel, cadmium determines its carcinogenic hazard. The elevated dustiness of the air is noted with the reflective and especially mine melting, due to the imperfection of the technological equipment and sanitary technical devices. Autogenous smelting processes have demonstrated their hygienic advantage over outdated methods of producing blister copper mining and smelting reflectivity.

Cu self-sputtering MD simulations for 0.1-5 keV ions at elevated temperatures

NASA Astrophysics Data System (ADS)

Metspalu, Tarvo; Jansson, Ville; Zadin, Vahur; Avchaciov, Konstantin; Nordlund, Kai; Aabloo, Alvo; Djurabekova, Flyura

2018-01-01

Self-sputtering of copper under high electric fields is considered to contribute to plasma buildup during a vacuum breakdown event frequently observed near metal surfaces, even in ultra high vacuum condition in different electric devices. In this study, by means of molecular dynamics simulations, we analyze the effect of surface temperature and morphology on the yield of self-sputtering of copper with ion energies of 0.1-5 keV. We analyze all three low-index surfaces of Cu, {1 0 0}, {1 1 0} and {1 1 1}, held at different temperatures, 300 K, 500 K and 1200 K. The surface roughness relief is studied by either varying the angle of incidence on flat surfaces, or by using arbitrary roughened surfaces, which result in a more natural distribution of surface relief variations. Our simulations provide detailed characterization of copper self-sputtering with respect to different material temperatures, crystallographic orientations, surface roughness, energies, and angles of ion incidence.

The Variations of Glycolysis and TCA Cycle Intermediate Levels Grown in Iron and Copper Mediums of Trichoderma harzianum.

PubMed

Tavsan, Zehra; Ayar Kayali, Hulya

2015-05-01

The efficiency of optimal metabolic function by microorganism depends on various parameters, especially essential metal supplementation. In the present study, the effects of iron and copper metals on metabolism were investigated by determination of glycolysis and tricarboxylic acid (TCA) cycle metabolites' levels with respect to the metal concentrations and incubation period in Trichoderma harzianum. The pyruvate and citrate levels of T. harzianum increased up to 15 mg/L of copper via redirection of carbon flux though glycolysis by suppression of pentose phosphate pathway (PPP). However, the α-ketoglutarate levels decreased at concentration higher than 5 mg/L of copper to overcome damage of oxidative stress. The fumarate levels correlated with the α-ketoglutarate levels because of substrate limitation. Besides, in T. harzianum cells grown in various concentrations of iron-containing medium, the intracellular pyruvate, citrate, and α-ketoglutarate levels showed positive correlation with iron concentration due to modifying of expression of glycolysis and TCA cycle enzymes via a mechanism involving cofactor or allosteric regulation. However, as a result of consuming of prior substrates required for fumarate production, its levels rose up to 10 mg/L.

Effects of acid-mine wastes on aquatic ecosystems

Treesearch

John David Parsons

1976-01-01

The Cedar Creek Basin (39th N parallel 92nd W meridian) was studied for the period June 1952 through August 1954 to observe the effects of both continuous and periodic acid effluent flows on aquatic communities. The acid strip-mine effluent contained ferric and ferrous iron, copper, lead, zinc, aluminum, magnesium, titratable acid, and elevated hydrogen ion...

Response to copper of Acidithiobacillus ferrooxidans ATCC 23270 grown in elemental sulfur.

PubMed

Almárcegui, Rodrigo J; Navarro, Claudio A; Paradela, Alberto; Albar, Juan Pablo; von Bernath, Diego; Jerez, Carlos A

2014-11-01

The response of Acidithiobacillus ferrooxidans ATCC 23270 to copper was analyzed in sulfur-grown cells by using quantitative proteomics. Forty-seven proteins showed altered levels in cells grown in the presence of 50 mM copper sulfate. Of these proteins, 24 were up-regulated and 23 down-regulated. As seen before in ferrous iron-grown cells, there was a notorious up-regulation of RND-type Cus systems and different RND-type efflux pumps, indicating that these proteins are very important in copper resistance. Copper also triggered the down-regulation of the major outer membrane porin of A. ferrooxidans in sulfur-grown bacteria, suggesting they respond to the metal by decreasing the influx of cations into the cell. On the contrary, copper in sulfur-grown cells caused an overexpression of putative TadA and TadB proteins known to be essential for biofilm formation in bacteria. Surprisingly, sulfur-grown microorganisms showed increased levels of proteins related with energy generation (rus and petII operons) in the presence of copper. Although rus operon is overexpressed mainly in cells grown in ferrous iron, the up-regulation of rusticyanin in sulfur indicates a possible role for this protein in copper resistance as well. Finally, copper response in A. ferrooxidans appears to be influenced by the substrate being oxidized by the microorganism. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Age of Supergene oxidation and enrichment in the chilean porphyry copper province

USGS Publications Warehouse

Sillitoe, R.H.; McKee, E.H.

1996-01-01

Twenty-five samples of supergene alunite collected from deeply developed supergene profiles in porphyry copper deposits and prospects between latitudes 20?? and 27?? S in northern Chile yield K/Ar ages ranging from about 34 to 14 Ma. Therefore supergene oxidation and enrichment processes were active from the early Oligocene to the middle Miocene, a minimum of 20 m.y. Supergene activity at individual deposits lasted for at least 0.4 to 6.2 m.y. The early Oligocene supergene activity affected deposits in the Paleocene porphyry copper belt, whereas early and middle Miocene supergene processes are documented in the Early Cretaceous, Paleocene, and late Eocene to early Oligocene porphyry copper belts. Middle Miocene oxidation also affected the oldest epithermal gold-silver deposits in the Maricunga belt farther east. Supergene activity commenced no less than 11 m.y. after generation of each porphyry copper deposit because of the time required to unroof the copper-bearing parts of the system. Supergene activity throughout northern Chile ceased at -14 Ma. The geologic features of deposits and prospects and their morphotectonic positions, present latitudes, and present elevations display no obvious correlations with the supergene chronology. Exploration for major cumulative enrichment blankets should not be carried out either beneath thick sequences of piedmont gravels (?? ignimbrites) of Oligocene through middle Miocene age unless their accumulation is demonstrably late in the documented history of supergene activity, or in porphyry copper provinces, such as those of central Chile and northwestern Argentina, which formed after ??? 14 Ma. The uplift responsible for efficient cumulative copper enrichment is difficult to correlate convincingly with the brief pulses of compressive tectonism postulated for northern Chile and contiguous areas unless their effects were much more prolonged. Intensifying aridity is confirmed as the likely reason for the cessation of supergene activity in northern Chile, and tectonic uplift was its most probable cause. However, more fundamental global controls producing a period of chemical weathering followed by worldwide dessication also may have played a role.

Lipid peroxidation and antioxidant status in workers exposed to PCDD/Fs of metal recovery plants.

PubMed

Chen, Hsiu-Ling; Hsu, Ching-Yi; Hung, Dong-Zong; Hu, Miao-Lin

2006-12-15

Secondary copper smelters, which primarily utilize the waste materials that contain organic impurities, and the zinc recovery plant, which handles mostly fly ash and slag from the iron and steel industry, are major emission sources of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in Taiwan. In this study, we compared the levels of erythrocyte glutathione (GSH), erythrocyte superoxide dismutase (SOD) and plasma malondialdehyde (MDA) in workers at a secondary copper smelting plant and a zinc recovery plant who may have been exposed to PCDD/Fs. Though the PCDD/F levels were higher in workers of zinc recovery plant than those of secondary copper smelting plant, no significant difference was found for serum PCDD/F levels between the two kinds of plants. We observed a significant difference in plasma MDA levels between workers at the zinc recovery plant (2.54 microM) and those at the copper smelting plant (1.79 microM). There was and a significant positive correlation between plasma MDA levels and the PCDD/Fs levels. In addition, we observed that the MDA levels were not affected by smoking and exercise status. Therefore, the data suggest that the MDA levels of the metal recovery workers are influenced by their PCDD/F exposure. The erythrocyte SOD activity in workers from the zinc recovery plant was marginally higher than that from the secondary copper plant (196 vs. 146 units/ml, p<0.06). In both plants, large variations in the MDA and SOD levels were found, especially in the high-PCDD/Fs-exposure group, which may be attributed, at least partially, to the differences in smoking status and the number of cigarettes smoked. Overall, our results indicate a higher oxidative stress in workers of the zinc recovery plant than in workers of the secondary copper smelting plant in Taiwan.

Multiple metal resistance in the cyanobacterium Nostoc muscorum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Verma, S.K.; Singh, S.P.

1995-04-01

Metal tolerant strains of microbes are likely to originate in habitats having elevated metal levels. This aspect has been reviewed quite extensively by Silvers and Misra and the suggested mechanism of metal tolerance are: (a) cellular exclusion of metals; (b) extrusion of metals; and (c) intracellular immobilization. Similar studies on cyanobacterial strains appear to have been initiated by Shehata and Whitton who isolated a Zn-tolerant strain of Anacystis nidulans displaying a Zn uptake comparable to the Zn-sensitive wild type. The metal tolerance in the above strain was attributed to the intracellular detoxification mechanisms as suggested for Plectonema boryanum and Nostocmore » calcicola. The Cd-resistant strain of A. nidulans showed a protection of Cd-induced growth inhibition due to reduce uptake of metal. Recently we reported an energy- and dilution-dependent efflux of copper as the mechanism of Cu tolerance in a copper-resistant strain of Nostoc calcicola. The above studies were concerned mainly with single-metal resistance in cyanobacteria. Since natural habitats are generally characterized by the coexistence of a large number of toxic and nontoxic cations, it is necessary to study multiple-metal response on the physiology and biochemistry of microorganisms. In the presence study, therefore, we describe a multiple metal resistant strain of the cyanobacterium Nostoc muscorum. 15 refs., 1 fig., 1 tab.« less

Experimenting with a Visible Copper-Aluminum Displacement Reaction in Agar Gel and Observing Copper Crystal Growth Patterns to Engage Student Interest and Inquiry

ERIC Educational Resources Information Center

Xu, Xinhua; Wu, Meifen; Wang, Xiaogang; Yang, Yangyiwei; Shi, Xiang; Wang, Guoping

2016-01-01

The reaction process of copper-aluminum displacement in agar gel was observed at the microscopic level with a stereomicroscope; pine-like branches of copper crystals growing from aluminum surface into gel at a constant rate were observed. Students were asked to make hypotheses on the pattern formation and design new research approaches to prove…

Phytostabilization potential of evening primrose (Oenothera glazioviana) for copper-contaminated sites.

PubMed

Guo, Pan; Wang, Ting; Liu, Yanli; Xia, Yan; Wang, Guiping; Shen, Zhenguo; Chen, Yahua

2014-01-01

A field investigation, field experiment, and hydroponic experiment were conducted to evaluate feasibility of using Oenothera glazioviana for phytostabilization of copper-contaminated soil. In semiarid mine tailings in Tongling, Anhui, China, O. glazioviana, a copper excluder, was a dominant species in the community, with a low bioaccumulation factor, the lowest copper translocation factor, and the lowest copper content in seed (8 mg kg(-1)). When O. glazioviana was planted in copper-polluted farmland soil in Nanjing, Jiangsu, China, its growth and development improved and the level of γ-linolenic acid in seeds reached 17.1%, compared with 8.73% in mine tailings. A hydroponic study showed that O. glazioviana had high tolerance to copper, low upward transportation capacity of copper, and a high γ-linolenic acid content. Therefore, it has great potential for the phytostabilization of copper-contaminated soils and a high commercial value without risk to human health.

Cellular copper homeostasis: current concepts on its interplay with glutathione homeostasis and its implication in physiology and human diseases.

PubMed

Bhattacharjee, Ashima; Chakraborty, Kaustav; Shukla, Aditya

2017-10-18

Copper is a trace element essential for almost all living organisms. But the level of intracellular copper needs to be tightly regulated. Dysregulation of cellular copper homeostasis leading to various diseases demonstrates the importance of this tight regulation. Copper homeostasis is regulated not only within the cell but also within individual intracellular compartments. Inactivation of export machinery results in excess copper being redistributed into various intracellular organelles. Recent evidence suggests the involvement of glutathione in playing an important role in regulating copper entry and intracellular copper homeostasis. Therefore interplay of both homeostases might play an important role within the cell. Similar to copper, glutathione balance is tightly regulated within individual cellular compartments. This review explores the existing literature on the role of glutathione in regulating cellular copper homeostasis. On the one hand, interplay of glutathione and copper homeostasis performs an important role in normal physiological processes, for example neuronal differentiation. On the other hand, perturbation of the interplay might play a key role in the pathogenesis of copper homeostasis disorders.

Heavy metals induce oxidative stress and trigger oxidative stress-mediated heat shock protein (hsp) modulation in the intertidal copepod Tigriopus japonicus.

PubMed

Kim, Bo-Mi; Rhee, Jae-Sung; Jeong, Chang-Bum; Seo, Jung Soo; Park, Gyung Soo; Lee, Young-Mi; Lee, Jae-Seong

2014-11-01

Heat shock proteins (hsps) are induced by a wide range of environmental stressors including heavy metals in aquatic organisms. However, the effect of heavy metals on zooplankton at the molecular level remains still unclear. In this study, we measured the intracellular reactive oxygen species (ROS) level and the antioxidant enzyme activities for 96 h after exposure to five heavy metals: arsenic (As), cadmium (Cd), copper (Cu), silver (Ag), and zinc (Zn) in the intertidal copepod Tigriopus japonicus. Activities of the antioxidant enzymes were highly elevated in metal-exposed copepods, indicating that heavy metals can induce oxidative stress by generating ROS, and stimulate the involvement of antioxidant enzymes as cellular defense mechanisms. Subsequently, transcriptional changes in hsp gene families were further investigated in the metal-exposed groups for 96 h. The ROS level and glutathione (GSH) content were significantly increased in Ag-, As-, and Cu-exposed copepods, while they were only slightly elevated in Cd- and Zn-exposed groups. Based on the numbers of significantly modulated hsp genes and their expression levels for 96 h, we measured the effect of heavy metals to stress genes of T. japonicus in the following order: Cu > Zn > Ag > As > Cd, implying that Cu acts as a stronger oxidative stress inducer than other heavy metals. Of them, the expression of hsp20 and hsp70 genes was substantially modulated by exposure to heavy metals, indicating that these genes would provide a sensitive molecular biomarker for aquatic monitoring of heavy metal pollution. Copyright © 2014 Elsevier Inc. All rights reserved.

Arsenic contamination in the Kanker district of central-east India: geology and health effects.

PubMed

Pandey, P K; Sharma, R; Roy, M; Roy, S; Pandey, M

2006-10-01

This paper identifies newer areas of arsenic contamination in the District Kanker, which adjoins the District Rajnandgaon where high contamination has been reported earlier. A correlation with the mobile phase episodes of arsenic contamination has been identified, which further hinges on the complex geology of the area. Arsenic concentrations in both surface and groundwater, aquatic organisms (snail and water weeds) soil and vegetation of Kanker district and its adjoining area have been reported here. The region has been found to contain an elevated level of arsenic. All segments of the ecoysystem are contaminated with arsenic at varying degrees. The levels of arsenic vary constantly depending on the season and location. An analysis of groundwater from 89 locations in the Kanker district has shown high values of arsenic, iron and manganese (mean: 144, 914 and 371 microg L(-1), respectively). The surface water of the region shows elevated levels of arsenic, which is influenced by the geological mineralised zonation. The most prevalent species in the groundwater is As(III), whereas the surface water of the rivers shows a significant contamination with the As(V) species. The analysis shows a bio-concentration of the toxic metals arsenic, nickel, copper and chromium. Higher arsenic concentrations (groundwater concentrations greater than 50 microg L(-1)) are associated with sedimentary deposits derived from volcanic rocks, hence mineral leaching appears to be the source of arsenic contamination. Higher levels of arsenic and manganese in the Kanker district have been found to cause impacts on the flora and fauna. A case study of episodic arsenical diarrhoea is presented.

Potential arsenic exposures in 25 species of zoo animals living in CCA-wood enclosures.

PubMed

Gress, J; da Silva, E B; de Oliveira, L M; Zhao, Di; Anderson, G; Heard, D; Stuchal, L D; Ma, L Q

2016-05-01

Animal enclosures are often constructed from wood treated with the pesticide chromated copper arsenate (CCA), which leaches arsenic (As) into adjacent soil during normal weathering. This study evaluated potential pathways of As exposure in 25 species of zoo animals living in CCA-wood enclosures. We analyzed As speciation in complete animal foods, dislodgeable As from CCA-wood, and As levels in enclosure soils, as well as As levels in biomarkers of 9 species of crocodilians (eggs), 4 species of birds (feathers), 1 primate species (hair), and 1 porcupine species (quills). Elevated soil As in samples from 17 enclosures was observed at 1.0-110mg/kg, and enclosures housing threatened and endangered species had As levels higher than USEPA's risk-based Eco-SSL for birds and mammals of 43 and 46mg/kg. Wipe samples of CCA-wood on which primates sit had dislodgeable As residues of 4.6-111μg/100cm(2), typical of unsealed CCA-wood. Inorganic As doses from animal foods were estimated at 0.22-7.8μg/kg bw/d. Some As levels in bird feathers and crocodilian eggs were higher than prior studies on wild species. However, hair from marmosets had 6.37mg/kg As, 30-fold greater than the reference value, possibly due to their inability to methylate inorganic As. Our data suggested that elevated As in soils and dislodgeable As from CCA-wood could be important sources of As exposure for zoo animals. Published by Elsevier B.V.

Evaluation of some heavy metals residues in batteries and deep litter rearing systems in Japanese quail meat and offal in Egypt

PubMed Central

Ahmed, Ali M.; Hamed, Dalia M.; Elsharawy, Nagwa T.

2017-01-01

Aim: The main objectives of this study were for comparing the effect of batteries and deep litter rearing systems of domesticated Japanese quail, Coturnix coturnix japonica, on the concentration levels of cadmium, copper, lead, and zinc from the quail meat and offal in Ismailia, Egypt. Materials and Methods: A total of 40 quail meat and their offal samples were randomly collected from two main quail rearing systems: Battery (Group I) and deep litter system (Group II) for determination of concentration levels of cadmium, copper, lead, and zinc. In addition, 80 water and feed samples were randomly collected from water and feeders of both systems in the Food Hygiene Laboratory, Faculty of Veterinary Medicine, Suez Canal University for heavy metals determination. Results: The mean concentration levels of cadmium, copper, lead, and zinc in Group I were 0.010, 0.027, 1.137, and 0.516 ppm and for Group II were 0.093, 0.832, 0.601, and 1.651 ppm, respectively. The mean concentration levels of cadmium, copper, lead, and zinc in quail feed in Group I were 1.114, 1.606, 5.822, and 35.11 ppm and for Group II were 3.010, 2.576, 5.852, and 23.616 ppm, respectively. The mean concentration levels of cadmium, copper, lead, and zinc in quail meat for Group I were 0.058, 5.902, 10.244, and 290 ppm and for Group II were 0.086, 6.092, 0.136, and 1.280 ppm, respectively. The mean concentration levels of cadmium, copper, lead, and zinc for liver samples in Group I were 0.15, 8.32, 1.05, and 3.41 ppm and for Group II were 0.13, 8.88, 0.95, and 4.21 ppm, respectively. The mean concentration levels of cadmium, copper, lead, and zinc in kidney samples for the Group I were 0.24, 4.21, 1.96, and 4.03 ppm and for Group II were 0.20, 5.00, 1.56, and 3.78 ppm, respectively. Kidney had the highest concentration levels of heavy metals followed by liver then muscles. The highest concentration levels of copper were observed in liver samples. The order of the levels of these trace elements obtained from the four different quail organs is Ca > Pb > Zn > Cu. Lead and cadmium concentration levels in quail meat samples were exceeded the Egyptian standardization limits and suggesting a health threat from lead and cadmium to the quail consumers. Conclusion: Battery rearing system is more hygienic than deep litter system from the point of heavy metals pollution of water and feeds of quail. Feed samples from battery system had means concentration levels of lead not significantly higher (p>0.05) than those samples from deep litter system. Meanwhile, water samples from battery system had means concentration levels of cadmium, copper, and zinc significantly higher (p>0.05) than those samples from deep litter system. Quail may carry health risks to consumers. PMID:28344413

Evaluation of some heavy metals residues in batteries and deep litter rearing systems in Japanese quail meat and offal in Egypt.

PubMed

Ahmed, Ali M; Hamed, Dalia M; Elsharawy, Nagwa T

2017-02-01

The main objectives of this study were for comparing the effect of batteries and deep litter rearing systems of domesticated Japanese quail, Coturnix coturnix japonica , on the concentration levels of cadmium, copper, lead, and zinc from the quail meat and offal in Ismailia, Egypt. A total of 40 quail meat and their offal samples were randomly collected from two main quail rearing systems: Battery (Group I) and deep litter system (Group II) for determination of concentration levels of cadmium, copper, lead, and zinc. In addition, 80 water and feed samples were randomly collected from water and feeders of both systems in the Food Hygiene Laboratory, Faculty of Veterinary Medicine, Suez Canal University for heavy metals determination. The mean concentration levels of cadmium, copper, lead, and zinc in Group I were 0.010, 0.027, 1.137, and 0.516 ppm and for Group II were 0.093, 0.832, 0.601, and 1.651 ppm, respectively. The mean concentration levels of cadmium, copper, lead, and zinc in quail feed in Group I were 1.114, 1.606, 5.822, and 35.11 ppm and for Group II were 3.010, 2.576, 5.852, and 23.616 ppm, respectively. The mean concentration levels of cadmium, copper, lead, and zinc in quail meat for Group I were 0.058, 5.902, 10.244, and 290 ppm and for Group II were 0.086, 6.092, 0.136, and 1.280 ppm, respectively. The mean concentration levels of cadmium, copper, lead, and zinc for liver samples in Group I were 0.15, 8.32, 1.05, and 3.41 ppm and for Group II were 0.13, 8.88, 0.95, and 4.21 ppm, respectively. The mean concentration levels of cadmium, copper, lead, and zinc in kidney samples for the Group I were 0.24, 4.21, 1.96, and 4.03 ppm and for Group II were 0.20, 5.00, 1.56, and 3.78 ppm, respectively. Kidney had the highest concentration levels of heavy metals followed by liver then muscles. The highest concentration levels of copper were observed in liver samples. The order of the levels of these trace elements obtained from the four different quail organs is Ca > Pb > Zn > Cu. Lead and cadmium concentration levels in quail meat samples were exceeded the Egyptian standardization limits and suggesting a health threat from lead and cadmium to the quail consumers. Battery rearing system is more hygienic than deep litter system from the point of heavy metals pollution of water and feeds of quail. Feed samples from battery system had means concentration levels of lead not significantly higher (p>0.05) than those samples from deep litter system. Meanwhile, water samples from battery system had means concentration levels of cadmium, copper, and zinc significantly higher (p>0.05) than those samples from deep litter system. Quail may carry health risks to consumers.

LEAD AND COPPER RESEARCH UPDATE: RECENT AND FUTURE AREAS OF WORK

EPA Science Inventory

Although the Lead and Copper Rule has been in place for over 10 years, many drinking water systems still have difficulty in meeting the lead and copper action levels. Some water quality conditions remain either difficult to treat or changes brought about by treatment changes dir...

A REVIEW OF ACID COPPER PLATING BATH LIFE EXTENSION AND COPPER RECOVERY FROM ACID COPPER BATHS

EPA Science Inventory

Large quantities of hazardous waste, most in aqueous solution or sludges, are being produced at numerous metal plating and processing facilities in the U.S. Regulatory pressures, future liability, and limited landfill space have driven the cost of metal waste disposal to level...

Investigation of the copper contents in vineyard soil, grape must and wine and the relationship among them in the Huaizhuo Basin Region, China: A preliminary study.

PubMed

Sun, Xiangyu; Ma, Tingting; Yu, Jing; Huang, Weidong; Fang, Yulin; Zhan, Jicheng

2018-02-15

The copper contents in vineyard soil, grape must and wine and the relationship among them in the Huaizhuo Basin Region, China, were investigated. The results showed that the copper pollution status in vineyard soils, grapes and wines in the investigated area in China is under control, with only 4 surface soil (0-20cm) samples over maximum residue limits (MRL) and no grape or wine samples over MRL. Different vineyards, grape varieties, vine ages, and training systems all significantly influenced the copper contents in the vineyard soils, grape and wines. Additionally, the copper levels in the vineyard soils, grapes and wines all had some correlation. In wine samples, the copper contents ranged from 0.52 to 663μg/L, which is only approximately one percent the level found in grapes and one ten-thousandth that found in soils. Of the wine samples, red wines showed a significantly higher copper content than white wines, while in the red/white grape and soil samples, no significant differences were observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Copper Pollution Increases the Resistance of Soil Archaeal Community to Changes in Water Regime.

PubMed

Li, Jing; Liu, Yu-Rong; Cui, Li-Juan; Hu, Hang-Wei; Wang, Jun-Tao; He, Ji-Zheng

2017-11-01

Increasing efforts have been devoted to exploring the impact of environmental stresses on soil bacterial communities, but the work on the archaeal community is seldom. Here, we constructed microcosm experiments to investigate the responses of archaeal communities to the subsequent dry-rewetting (DW) disturbance in two contrasting soils (fluvo-aquic and red soil) after 6 years of copper pollution. Ten DW cycles were exerted on the two soils with different copper levels, followed by a 6-week recovery period. In both soils, archaeal diversity (Shannon index) in the high copper-level treatments increased over the incubation period, and archaeal community structure changed remarkably as revealed by the non-metric multidimensional scaling ordinations. In both soils, copper pollution altered the response of dominant operational taxonomic units (OTUs) to the DW disturbance. Throughout the incubation and recovery period, the resistance of archaeal abundance to the DW disturbance was higher in the copper-polluted soils than soils without pollution. Taken together, copper pollution altered the response of soil archaeal diversity and community composition to the DW disturbance and increased the resistance of the archaeal abundance. These findings have important implications for understanding soil microbial responses to ongoing environmental change.

The effects of copper fining on the wine content in sulfur off-odors and on their evolution during accelerated anoxic storage.

PubMed

Vela, Eduardo; Hernández-Orte, Purificación; Franco-Luesma, Ernesto; Ferreira, Vicente

2017-09-15

Three different red wines with reductive character have been treated with two different doses of copper sulfate (0.06 and 0.5mg/L) and with a commercial copper-containing product at the recommended dose (0.6mg/L). Wines were in contact with copper one week, centrifuged and stored at 50°C in strict anoxia for 2weeks (up to 7 in one case). Brine-releasable (BR-) and free fractions of Volatile Sulfur Compounds were determined throughout the process. Relevant increases of BR-H 2 S suggest that those wines contained other H 2 S precursors non-detectable by the brine dilution method. Copper treatments had two major effects: 1) immediate decrease the levels of free H 2 S and methanethiol (MeSH); 2) slow the rate at which free H 2 S (not MeSH) increases during anoxic storage. After 7weeks of anoxia levels of free H 2 S and MeSH were high and similar regardless of the copper treatment. Higher copper doses could induce the accumulation of BR-H 2 S. Copyright © 2017 Elsevier Ltd. All rights reserved.

Uplift and submarine formation of some Melanesian porphyry copper deposits: Stable isotope evidence

USGS Publications Warehouse

Chivas, A.R.; O'Neil, J.R.; Katchan, G.

1984-01-01

Hydrogen and oxygen isotope analyses of sericites and kaolinites from four young porphyry copper deposits (Ok Tedi (1.2 Ma) and Yandera (6.5 Ma), Papua New Guinea; Koloula (1.5 Ma), Solomon Islands; and Waisoi (<5 Ma), Fiji) indicate that the fluids from which these minerals precipitated were of mixed magmatic and non-magmatic sources. The non-magmatic component of the fluid from the island arc deposits (Koloula, Waisoi) was ocean water. For Ok Tedi, the non-magmatic component was a meteoric water with an isotopic composition different from that of the present meteoric water in the region. The isotopic signature of the former meteoric water is consistent with a surface elevation of 200 m a.s.l. or less at the time of mineralization. The deposit was later exposed and supergene kaolinitization commenced at approximately 1200 m a.s.l. Uplift and erosion has continued to the present at which time the elevation of the exposed deposit is 1800 m a.s.l. This rate of uplift is consistent with that known from other geological evidence. If the rate of uplift were approximately constant during the last 1.2 Ma, the age of supergene enrichment can be dated at approximately 0.4 Ma B.P. Similarly, influx of meteoric water at Yandera occurred when the ground surface above the deposit was at an elevation of approximately 600 m a.s.l. The deposit's present elevation is 1600 m a.s.l. In this case a total uplift of approximately 2.2 km is indicated, with removal of 1.2 km of overburden by erosion. ?? 1984.

Fluorescence Lifetime Imaging of Physiological Free Cu(II) Levels in Live Cells with a Cu(II)-Selective Carbonic Anhydrase-Based Biosensor

PubMed Central

McCranor, Bryan J.; Szmacinski, Henryk; Zeng, Hui Hui; Stoddard, A.K.; Hurst, Tamiika; Fierke, Carol A.; Lakowicz, J.R.

2014-01-01

Copper is a required trace element that plays key roles in a number of human enzymes, such that copper deficiency or genetic defects in copper transport lead to serious or fatal disease. Rae, et al., had famously predicted that free copper ion levels in the cell cytoplasm were extremely low, typically too low to be observable. We recently developed a variant of human apocarbonic anhydrase II for sensing metal ions that exhibits 25-fold better selectivity for Cu(II) over Zn(II) than the wild type protein, enabling us to accurately measure Cu(II) in the presence of ordinary cellular (picomolar) concentrations of free zinc. We inserted a fluorescent labeled Cu(II)-specific variant of human apocarbonic anhydrase into PC-12 cells and found that the levels are indeed extremely low (in the femtomolar range). We imaged the free Cu(II) levels in living cells by means of frequency-domain fluorescence lifetime microscopy. Implications of this finding are discussed. PMID:24671220

Concentrations and Distribution of Slag-Related Trace Elements and Mercury in Fine-Grained Beach and Bed Sediments of Lake Roosevelt, Washington, April-May 2001

USGS Publications Warehouse

Majewski, Michael S.; Kahle, Sue C.; Ebbert, James C.; Josberger, Edward G.

2003-01-01

A series of studies have documented elevated concentrations of trace elements such as arsenic, cadmium, copper, lead, mercury, and zinc in the water, bed sediment, or fish of Lake Roosevelt and the upstream reach of the Columbia River. Elevated concentrations of some trace elements in this region are largely attributable to the transport of slag and metallurgical waste discharged into the Columbia River from a smelter in Canada. Although most recent studies have focused on contamination levels in water, bed sediment, and fish, there is growing concern in the region over the potential threat of airborne contaminants to human health. In response to these concerns, the U.S. Geological Survey conducted an assessment of trace-element concentrations in the relatively shallow fine-grained sediment along the shore of Lake Roosevelt that is exposed annually during periods of reservoir drawdown. During each winter and spring, the water level of Lake Roosevelt is lowered as much as about 80 feet to provide space to capture high river flows from spring runoff, exposing vast expanses of lake-bottom sediment for a period of several months. Upon drying, these exposed areas provide an extremely large source for wind-blown dust. This study concluded that trace elements associated with slag and metallurgical waste are present in the fine-grained fraction (less than 63 micrometers) of bed sediments along the length of Lake Roosevelt, and as such, could be components of the airborne dust resulting from exposure, drying, and wind mobilization of the sediments exposed during the annual drawdowns of the reservoir. Trace-element concentrations in the surficial bed sediment varied, but the major components in slag?arsenic, cadmium, copper, lead, and zinc?showed generally pronounced gradients of decreasing concentrations from near the International Border to the Grand Coulee Dam. The results of this study provide base-line information needed to plan and conduct air monitoring of trace elements in wind-blown dust along Lake Roosevelt.

Zinc Pyrithione Inhibits Yeast Growth through Copper Influx and Inactivation of Iron-Sulfur Proteins▿†

PubMed Central

Reeder, Nancy L.; Kaplan, Jerry; Xu, Jun; Youngquist, R. Scott; Wallace, Jared; Hu, Ping; Juhlin, Kenton D.; Schwartz, James R.; Grant, Raymond A.; Fieno, Angela; Nemeth, Suzanne; Reichling, Tim; Tiesman, Jay P.; Mills, Tim; Steinke, Mark; Wang, Shuo L.; Saunders, Charles W.

2011-01-01

Zinc pyrithione (ZPT) is an antimicrobial material with widespread use in antidandruff shampoos and antifouling paints. Despite decades of commercial use, there is little understanding of its antimicrobial mechanism of action. We used a combination of genome-wide approaches (yeast deletion mutants and microarrays) and traditional methods (gene constructs and atomic emission) to characterize the activity of ZPT against a model yeast, Saccharomyces cerevisiae. ZPT acts through an increase in cellular copper levels that leads to loss of activity of iron-sulfur cluster-containing proteins. ZPT was also found to mediate growth inhibition through an increase in copper in the scalp fungus Malassezia globosa. A model is presented in which pyrithione acts as a copper ionophore, enabling copper to enter cells and distribute across intracellular membranes. This is the first report of a metal-ligand complex that inhibits fungal growth by increasing the cellular level of a different metal. PMID:21947398

Plastocyanin Controls the Stabilization of the Thylakoid Cu-transporting P-type ATPase PAA2/HMA8 in Response to Low Copper in Arabidopsis*

PubMed Central

Tapken, Wiebke; Ravet, Karl; Pilon, Marinus

2012-01-01

PAA2/HMA8 (P-type ATPase of Arabidopsis/Heavy-metal-associated 8) is a thylakoid located copper (Cu)-transporter in Arabidopsis thaliana. In tandem with PAA1/HMA6, which is located in the inner chloroplast envelope, it supplies Cu to plastocyanin (PC), an essential cuproenzyme of the photosynthetic machinery. We investigated whether the chloroplast Cu transporters are affected by Cu addition to the growth media. Immunoblots showed that PAA2 protein abundance decreased significantly and specifically when Cu in the media was increased, while PAA1 remained unaffected. The function of SPL7, the transcriptional regulator of Cu homeostasis, was not required for this regulation of PAA2 protein abundance and Cu addition did not affect PAA2 transcript levels, as determined by qRT-PCR. We used the translational inhibitor cycloheximide to analyze turnover and observed that the stability of the PAA2 protein was decreased in plants grown with elevated Cu. Interestingly, PAA2 protein abundance was significantly increased in paa1 mutants, in which the Cu content in the chloroplast is half of that of the wild-type, due to impaired Cu import into the organelle. In contrast in a pc2 insertion mutant, which has strongly reduced plastocyanin expression, the PAA2 protein levels were low regardless of Cu addition to the growth media. Together, these data indicate that plastid Cu levels control PAA2 stability and that plastocyanin, which is the target of PAA2 mediated Cu delivery in thylakoids, is a major determinant of this regulatory mechanism. PMID:22493454

[Estimation of mercury in the urine of cigarette smokers].

PubMed

Kulikowska-Karpińska, Elżbieta; Zdanowicz, Magdalena; Gałażyn-Sidorczuk, Małgorzata

Cigarette smoking is one of the most common habits of the modern world. According to a NATPOL PLU study, every third adult Pole is dependent on nicotine. Tobacco smoke contains about 5,000 components, of which over 1,000 are very toxic chemical substances (3,4-benzopyrene, heavy metals, free radicals, hydrogen cyanide, nitrogen oxides and N-nitrosamines). Exposure to tobacco smoke is an example of a complex, with a significant number of interactions. To assess the concentration of copper in the urine of smokers. Based on the results, an attempt was made to determine whether smoking can affect the level of copper in the body. The study involved 170 healthy volunteers, 99 smokers and 71 non-smokers (control group). The age of patients in both groups were in the range of 20-60 years. The mean age for men and women was 41 years. The average length of cigarette smoking was 18 years for women and 21 years for men, and the number of cigarettes smoked 1-40 ⁄ 24. The urine concentrations of Cu were determined by atomic absorption spectrometry (AAS) and serum creatinine kinetic method using a set of BIOLAB. Cu concentration in urine was expressed in mg / g creatinine. Smokers were found to have reduced levels of copper in the urine, depending on sex, age and brand of cigarettes. In male smokers, copper concentration in the urine was dependent on age and time of smoking, whereas among women this relationship was not observed. Cigarette smoking significantly influences the level of copper in the urine. Both female and male smokers showed reduced levels of copper in the urine, which may indicate its increased accumulation in the body. Excessive accumulation of copper is very dangerous since it may exhibit toxic effects towards many organs and systems.

Development of a tightly regulated and highly responsive copper-inducible gene expression system and its application to control of flowering time.

PubMed

Saijo, Takanori; Nagasawa, Akitsu

2014-01-01

A newly developed copper-inducible gene expression system overcame the mixed results reported earlier, worked well both in cultured cells and a whole plant, and enabled to control flowering timing. Copper is one of the essential microelements and is readily taken up by plants. However, to date, it has rarely been used to control the expression of genes of interest, probably due to the inefficiency of the gene expression systems. In this study, we successfully developed a copper-inducible gene expression system that is based on the regulation of the yeast metallothionein gene. This system can be applied in the field and regulated at approximately one-hundredth of the rate used for registered copper-based fungicides. In the presence of copper, a translational fusion of the ACE1 transcription factor with the VP16 activation domain (VP16AD) of herpes simplex virus strongly activated transcription of the GFP gene in transgenic Arabidopsis. Interestingly, insertion of the To71 sequence, a 5'-untranslated region of the 130k/180k gene of tomato mosaic virus, upstream of the GFP gene reduced the basal expression of GFP in the absence of copper to almost negligible levels, even in soil-grown plants that were supplemented with ordinary liquid nutrients. Exposure of plants to 100 μM copper resulted in an over 1,000-fold induction ratio at the transcriptional level of GFP. This induction was copper-specific and dose-dependent with rapid and reversible responses. Using this expression system, we also succeeded in regulating floral transition by copper treatment. These results indicate that our newly developed copper-inducible system can accelerate gene functional analysis in model plants and can be used to generate novel agronomic traits in crop species.

Levels of heavy metals and essential minerals in hair samples of children with autism in Oman: a case-control study.

PubMed

Al-Farsi, Yahya M; Waly, Mostafa I; Al-Sharbati, Marwan M; Al-Shafaee, Mohammed A; Al-Farsi, Omar A; Al-Khaduri, Maha M; Gupta, Ishita; Ouhtit, Allal; Al-Adawi, Samir; Al-Said, Mona F; Deth, Richard C

2013-02-01

Toxic levels of heavy metals and low levels of essential minerals have been suggested to play a critical role in the pathogenesis of autism spectrum disorders (ASD). This study documents the levels of heavy metals and essential minerals in hair samples of children with ASD in Muscat, the urbanized capital of Oman, Muscat. The study included 27 children with ASD and 27 matched non-ASD controls. Parental interviews were held and dietary intake questionnaires completed in conjunction with the collection of hair samples. Analysis of heavy metals and essential minerals was carried out by inductively coupled plasma mass spectrometry. Chi-square analysis and non-parametric Fisher's exact tests were used to assess statistical significance. Children with ASD had significantly higher levels of all 11 analyzed heavy metals in their hair samples (P < 0.05), ranging from 150 to 365 % of control levels. ASD children also had significantly higher levels of essential minerals sulfur, sodium, magnesium, potassium, zinc, and iron, but lower levels of calcium and copper in their hair samples. This study corroborates data from previous studies in different parts of the world indicating the presence of elevated levels of heavy metals and selective depletion of essential minerals in the hair of children with ASD.

Studies on the feeding of cupric sulfate pentahydrate and cupric citrate to broiler chickens.

PubMed

Pesti, G M; Bakalli, R I

1996-09-01

Male commercial broiler strain chickens were fed either a control diet (based on corn and soybean meal) or the control diet supplemented with cupric sulfate pentahydrate or cupric citrate in seven experiments (six in floor pens, one in wire-floored batteries). In Experiment 1, feeding 125 or 250 mg/kg copper increased growth (4.9%) and decreased feed conversion ratios (3.4%), total plasma cholesterol (40.2%), and breast muscle cholesterol (37.0%). Feeding 375 mg/kg copper was without further beneficial effect. In Experiment 2, withdrawing growth promoting supplements of copper from the feed for the last 7 d caused a significant (P < 0.05) increase in breast muscle cholesterol at 42 d of age: 57.2, 48.0, and 43.2 mg/100 g meat for birds supplemented for 0, 35, or 42 d, respectively. Feeding 10 vs 260 mg/kg copper caused only small increases in tissue copper levels: 0.36 vs 0.41 mg/kg for breast meat, and 0.48 vs 0.60 mg/kg for thigh meat, respectively. Litter copper accumulations in these experiments were similar to those of earlier reports. Breast muscle cholesterol was reduced by feeding 125 mg/kg supplemental copper from cupric citrate (27.84 mg/100 g) or 125 mg supplemental copper from cupric sulfate pentahydrate (25.32 mg/100 g) compared to broilers fed the control diet (43.92 mg/100 g). Cupric citrate was efficacious for growth promotion at lower copper levels than cupric sulfate pentahydrate, resulting in reduced litter copper.

A Prospective Study of Serum Trace Elements in Healthy Korean Pregnant Women

PubMed Central

Choi, Rihwa; Sun, Jiyu; Yoo, Heejin; Kim, Seonwoo; Cho, Yoon Young; Kim, Hye Jeong; Kim, Sun Wook; Chung, Jae Hoon; Oh, Soo-young; Lee, Soo-Youn

2016-01-01

This prospective study sought to investigate serum levels of trace elements (cobalt, copper, zinc, and selenium) and to assess their effects on pregnancy and neonatal outcomes. Serum levels of trace elements in 245 Korean pregnant women (median gestational age at delivery was 39 + 4 weeks and interquartile range was 38 + 4–40 + 1 weeks) were compared with those of 527 general adults and those of previous studies in other ethnic groups. Pregnancy and neonatal outcomes including gestational diabetes, preeclampsia, neonatal birth weight, and congenital abnormalities were assessed. The median serum trace element concentrations of all pregnant women were: cobalt: 0.39 μg/L (interquartile range, IQR 0.29–0.53), copper: 165.0 μg/dL (IQR 144.0–187.0), zinc: 57.0 μg/dL (IQR 50.0–64.0), and selenium: 94.0 μg/L (IQR 87.0–101.0). Serum cobalt and copper concentrations were higher in pregnant women than in the general population, whereas zinc and selenium levels were lower (p < 0.01). Concentrations of all four trace elements varied significantly during the three trimesters (p < 0.05), and seasonal variation was found in copper, zinc, and selenium, but was not observed for cobalt. The prevalence of preeclampsia was significantly lower with high copper (p = 0.03). Trace element levels varied by pregnancy trimester and season, and alteration in copper status during pregnancy might influence pregnancy outcomes such as preeclampsia. PMID:27886083

A Prospective Study of Serum Trace Elements in Healthy Korean Pregnant Women.

PubMed

Choi, Rihwa; Sun, Jiyu; Yoo, Heejin; Kim, Seonwoo; Cho, Yoon Young; Kim, Hye Jeong; Kim, Sun Wook; Chung, Jae Hoon; Oh, Soo-Young; Lee, Soo-Youn

2016-11-23

This prospective study sought to investigate serum levels of trace elements (cobalt, copper, zinc, and selenium) and to assess their effects on pregnancy and neonatal outcomes. Serum levels of trace elements in 245 Korean pregnant women (median gestational age at delivery was 39 + 4 weeks and interquartile range was 38 + 4-40 + 1 weeks) were compared with those of 527 general adults and those of previous studies in other ethnic groups. Pregnancy and neonatal outcomes including gestational diabetes, preeclampsia, neonatal birth weight, and congenital abnormalities were assessed. The median serum trace element concentrations of all pregnant women were: cobalt: 0.39 μg/L (interquartile range, IQR 0.29-0.53), copper: 165.0 μg/dL (IQR 144.0-187.0), zinc: 57.0 μg/dL (IQR 50.0-64.0), and selenium: 94.0 μg/L (IQR 87.0-101.0). Serum cobalt and copper concentrations were higher in pregnant women than in the general population, whereas zinc and selenium levels were lower ( p < 0.01). Concentrations of all four trace elements varied significantly during the three trimesters ( p < 0.05), and seasonal variation was found in copper, zinc, and selenium, but was not observed for cobalt. The prevalence of preeclampsia was significantly lower with high copper ( p = 0.03). Trace element levels varied by pregnancy trimester and season, and alteration in copper status during pregnancy might influence pregnancy outcomes such as preeclampsia.

Copper tolerance and copper accumulation of herbaceous plants colonizing inactive California copper mines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruckeberg, A.L.; Wu, L.

1992-06-01

Herbaceous plant species colonizing four copper mine waste sites in northern California were investigated for copper tolerance and copper accumulation. Copper tolerance was found in plant species colonizing soils with high concentrations of soil copper. Seven of the eight plant species tested were found at more than one copper mine. The mines are geographically isolated, which makes dispersal of seeds from one mine to another unlikely. Tolerance has probably evolved independently at each site. The nontolerant field control population of Vulpia microstachya displays significantly higher tolerance to copper at all copper concentration levels tested than the nontolerant Vulpia myrous population,more » and the degree of copper tolerance attained by V. microstachya at the two copper mines was much greater than that found in V. myrous. It suggests that even in these two closely related species, the innate tolerance in their nontolerant populations may reflect their potential for evolution of copper tolerance and their ability to initially colonize copper mine waste sites. The shoot tissue of the copper mine plants of Arenaria douglasii, Bromous mollis, and V. microstachya accumulated less copper than those plants of the same species from the field control sites when the two were grown in identical conditions in nutrient solution containing copper. The root tissue of these mine plants contain more copper than the roots of the nonmine plants. This result suggests that exclusion of copper from the shoots, in part by immobilization in the roots, may be a feature of copper tolerance. No difference in the tissue copper concentration was detected between tolerant and nontolerant plants of Lotus purshianus, Lupinus bicolor, and Trifolium pratense even though the root tissue had more copper than the leaves.« less

Influence of folic acid, pyridoxal phosphate and cobalamin on plasma homocyst(e)ine levels and the susceptibility of low-density lipoprotein to ex-vivo oxidation.

PubMed

Weiss, N; Feussner, A; Hailer, S; Spengel, F A; Keller, C; Wolfram, G

1999-10-15

Mild hyperhomocyst(e)inaemia is a risk factor for atherosclerotic vascular disease. In-vitro studies have shown that autooxidation of homocyst(e)ine is accompanied by the generation of oxygen radicals. This may lead to oxidative modification of low-density lipoproteins (LDL) and promote atherosclerotic vascular lesions. In male patients with peripheral arterial occlusive disease we determined fasting and post methionine load homocyst(e)ine levels by high performance liquid chromatography and the susceptibility of their LDL particles to ex-vivo oxidation by continously measuring the conjugated diene production induced by incubation with copper ions. Oxidation resistance (expressed as lag time), maximal oxidation rate, and extent of oxidation (expressed of total diene production) of LDL from patients with normal or mildly elevated homocyst(e)ine levels did not differ significantly. Folic acid, pyridoxal phosphate and cobalamin supplementation significantly decreased plasma homocyst(e)ine levels in hyperhomocyst(e)inaemic patients. This went along with a significant decrease in the extent of LDL oxidation and additionally increased HDL-cholesterol levels. The clinical relevance of these findings for the long-term course of atherosclerotic vascular disorders has to be determined by intervention studies.

Reactive solute transport in streams: A surface complexation approach for trace metal sorption

USGS Publications Warehouse

Runkel, Robert L.; Kimball, Briant A.; McKnight, Diane M.; Bencala, Kenneth E.

1999-01-01

A model for trace metals that considers in-stream transport, metal oxide precipitation-dissolution, and pH-dependent sorption is presented. Linkage between a surface complexation submodel and the stream transport equations provides a framework for modeling sorption onto static and/or dynamic surfaces. A static surface (e.g., an iron- oxide-coated streambed) is defined as a surface with a temporally constant solid concentration. Limited contact between solutes in the water column and the static surface is considered using a pseudokinetic approach. A dynamic surface (e.g., freshly precipitated metal oxides) has a temporally variable solid concentration and is in equilibrium with the water column. Transport and deposition of solute mass sorbed to the dynamic surface is represented in the stream transport equations that include precipitate settling. The model is applied to a pH-modification experiment in an acid mine drainage stream. Dissolved copper concentrations were depressed for a 3 hour period in response to the experimentally elevated pH. After passage of the pH front, copper was desorbed, and dissolved concentrations returned to ambient levels. Copper sorption is modeled by considering sorption to aged hydrous ferric oxide (HFO) on the streambed (static surface) and freshly precipitated HFO in the water column (dynamic surface). Comparison of parameter estimates with reported values suggests that naturally formed iron oxides may be more effective in removing trace metals than synthetic oxides used in laboratory studies. The model's ability to simulate pH, metal oxide precipitation-dissolution, and pH-dependent sorption provides a means of evaluating the complex interactions between trace metal chemistry and hydrologic transport at the field scale.

Concentrations of selected trace elements in fish tissue and streambed sediment in the Clark Fork-Pend Oreille and Spokane River basins, Washington, Idaho, and Montana, 1998

USGS Publications Warehouse

Maret, Terry R.; Skinner, K.D.

2000-01-01

Fish tissue and bed sediment samples were collected from 16 stream sites in the Northern Rockies Intermontane Basins study area in 1998 as part of the U.S. Geological Survey National Water-Quality Assessment Program. Bed sediment samples were analyzed for 45 trace elements, and fish livers and sportfish fillets were analyzed for 22 elements to characterize the occurrence and distribution of these elements in relation to stream characteristics and land use activities. Nine trace elements of environmental concern—arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, and zinc—were detected in bed sediment, but not all of these elements were detected in fish tissue. Trace-element concentrations were highest in bed sediment samples collected at sites downstream from significant natural mineral deposits and (or) mining activities. Arsenic, cadmium, copper, lead, mercury, and zinc in bed sediment at some sites were elevated relative to national median concentrations, and some concentrations were at levels that can adversely affect aquatic biota. Although trace-element concentrations in bed sediment exceeded various guidelines, no concentrations in sportfish fillets exceeded U.S. Environmental Protection Agency screening values for the protection of human health. Correlations between most trace-element concentrations in bed sediment and fish tissue (liver and fillet) were not significant (r0.05). Concentrations of arsenic, cadmium, copper, lead, mercury, nickel, selenium, and zinc in bed sediment were significantly correlated (r=0.53 to 0.88, p2=0.95 and 0.99, p<0.001) that corresponded to trace-element enrichment categories. These strong relations warrant further study using mine density as an explanatory variable to predict trace-element concentrations in bed sediment.

Investigation of the interaction of copper(II) oxide and electron beam irradiation crosslinkable polyethylene

NASA Astrophysics Data System (ADS)

Bee, Soo-Tueen; Sin, Lee Tin; Ratnam, C. T.; Haraveen, K. J. S.; Tee, Tiam-Ting; Rahmat, A. R.

2015-10-01

In this study, the effects of electron beam irradiation on the properties of copper(II) oxide when added to low-density polyethylene (LDPE) blends were investigated. It was found that the addition of low loading level of copper(II) oxide (⩽2 phr) to LDPE results in significantly poorer gel content and hot set results. However, the incorporation of higher loading level of copper(II) oxide (⩾3 phr) could slightly increase the degree of crosslinking in all irradiated LDPE composites. This is due to the fact that higher amounts of copper(II) oxide could slightly induce the formation of free radicals in LDPE matrix. Besides, increasing irradiation doses was also found to gradually increase the gel content of LDPE composites by generating higher amounts of free radicals. As a consequence, these higher amounts of free radicals released in the LDPE matrix could significantly increase the degree of crosslinking. The addition of copper(II) oxide could reduce the tensile strength and fracture strain (elongation at break) of LDPE composites because of poorer interfacial adhesion effect between copper(II) oxide particles and LDPE matrix. Meanwhile, increasing irradiation doses on all copper(II) oxide added LDPE composites could marginally increase the tensile strength. In addition, increasing irradiation dose could enhance the thermal stability of LDPE composites by increasing the decomposition temperature. The oxidation induction time (OIT) analysis showed that, because of the crosslinking network in the copper(II) oxide added LDPE composites, oxidation reaction is much delayed.

Risk of antibiotic resistance from metal contaminated soils

NASA Astrophysics Data System (ADS)

Knapp, Charles

2013-04-01

It is known that contaminated soils can lead to increased incidence of illness and disease, but it may also prevent our ability to fight disease. Many antibiotic resistant genes (ARG) acquired by bacteria originate from the environment. It is important to understand factors that influence levels of ARG in the environment, which could affect us clinically and agriculturally. The presence of elevated metal content in soils often promotes antibiotic resistance in exposed microorganisms. Using qPCR, the abundances of ARG to compare levels with geochemical conditions in randomly selected soils from several countries. Many ARG positively correlated with soil metal content, especially copper, chromium, nickel, lead, and iron. Results suggest that geochemical metal conditions influence the potential for antibiotic resistance in soil, which might be used to estimate baseline gene presence on various landscape scales and may translate to epidemiological risk of antibiotic-resistance transmission from the environment. This suggests that we may have to reconsider tolerances of metal pollution in the environment.

Physicochemical studies on Uburu Salt Lake Ebonyi State-Nigeria.

PubMed

Akubugwo, I E; Ofoegbu, C J; Ukwuoma, C U

2007-09-15

Physicochemical properties of soil (sediment) and water from Uburu salt lake were evaluated and compared with control soil and surface water from the same community. Results showed significant (p < 0.05) higher values for the heavy metals cadmium, chromium, copper, lead and zinc in the lake water relative to the control. The values of these metals in the lake soil (sediments) however, were significantly (p < 0.05) lower than the control soil. Similar significant (p < 0.05) elevations were observed in the lake water temperature, salinity, pH, calcium, magnesium, sodium, potassium, nitrate, carbonate, sulphate and phosphate levels compared to the control. Significant (p < 0.05) changes were also noted in the lake soil's pH, exchangeable acidity, nitrogen, organic carbon, calcium and magnesium levels. Also the soil texture was affected relative to the control. In a number of cases, the values of the studied parameters were higher than the permissible WHO standards. In view of these findings, cautious use of the salt lake soil and water is advocated.

Macrobenthic community response to copper in Shelter Island Yacht Basin, San Diego Bay, California.

PubMed

Neira, Carlos; Mendoza, Guillermo; Levin, Lisa A; Zirino, Alberto; Delgadillo-Hinojosa, Francisco; Porrachia, Magali; Deheyn, Dimitri D

2011-04-01

We examined Cu contamination effects on macrobenthic communities and Cu concentration in invertebrates within Shelter Island Yacht Basin, San Diego Bay, California. Results indicate that at some sites, Cu in sediment has exceeded a threshold for "self defense" mechanisms and highlight the potential negative impacts on benthic faunal communities where Cu accumulates and persists in sediments. At sites with elevated Cu levels in sediment, macrobenthic communities were not only less diverse but also their total biomass and body size (individual biomass) were reduced compared to sites with lower Cu. Cu concentration in tissue varied between species and within the same species, reflecting differing abilities to "regulate" their body load. The spatial complexity of Cu effects in a small marina such as SIYB emphasizes that sediment-quality criteria based solely on laboratory experiments should be used with caution, as they do not necessarily reflect the condition at the community and ecosystem levels. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evaluation of wound healing activity of ferulic acid in diabetic rats.

PubMed

Ghaisas, Mahesh M; Kshirsagar, Shashank B; Sahane, Rajkumari S

2014-10-01

In diabetic patients, there is impairment in angiogenesis, neovascularisation and failure in matrix metalloproteineases (MMPs), keratinocyte and fibroblast functions, which affects wound healing mechanism. Hence, diabetic patients are more prone to infections and ulcers, which finally result in gangrene. Ferulic acid (FA) is a natural antioxidant found in fruits and vegetables, such as tomatoes, rice bran and sweet corn. In this study, wound healing activity of FA was evaluated in streptozotocin-induced diabetic rats using excision wound model. FA-treated wounds were found to epithelise faster as compared with diabetic wound control group. The hydroxyproline and hexosamine content increased significantly when compared with diabetic wound control. FA effectively inhibited the lipid peroxidation and elevated the catalase, superoxide dismutase, glutathione and nitric oxide levels along with the increase in the serum zinc and copper levels probably aiding the wound healing process. Hence, the results indicate that FA significantly promotes wound healing in diabetic rats. © 2012 The Authors. International Wound Journal © 2012 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Utilising caging techniques to investigate metal assimilation in Nucella lapillus, Mytilus edulis and Crassostrea gigas at three Irish coastal locations

NASA Astrophysics Data System (ADS)

Giltrap, Michelle; Macken, Ailbhe; Davoren, Maria; McGovern, Evin; Foley, Barry; Larsen, Martin; White, Jonathan; McHugh, Brendan

2013-11-01

Pollution by metals has been of increasing concern for a number of decades but at present, the mechanism of metal accumulation in sentinel species is not fully understood and further studies are required for environmental risk assessment of metals in aquatic environments. The use of caging techniques has proven to be useful for assessment of water quality in coastal and estuarine environments. This study investigates the application of caging techniques for monitoring uptake of 20 elements [Li, Na, Mg, Al, P, K, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, As, Sb, Pb, Hg, Cd and Zn] in three marine species namely Nucella lapillus, Mytilus edulis and Crassostrea gigas. Stable isotopes were used to determine predatory effects and also used for modelling metal uptake in test species and to track nutrient assimilation. Metal levels were monitored at three different coastal locations, namely Dublin Bay, Dunmore East and Omey Island over 18 weeks. Significant differences in concentrations of Mn, Co and Zn between mussels and oysters were found. Correlations between cadmium levels in N. lapillus and δ13C and δ15N suggest dietary influences in Cd uptake. Levels of Zn were highest in C. gigas compared to the other two species and levels of Zn were most elevated at the Dunmore East site. Copper levels were more elevated in all test species at both Dublin Bay and Dunmore East. Mercury was raised in all species at Dunmore East compared to the other two sites. Biotic accumulation of metals in the test species demonstrates that caging techniques can provide a valid tool for biomonitoring in metal impacted areas.

Economic booms and risky sexual behavior: evidence from Zambian copper mining cities.

PubMed

Wilson, Nicholas

2012-12-01

Existing studies suggest that individual and household level economic shocks affect the demand for and supply of risky sex. However, little evidence exists on the effects of an aggregate shock on equilibrium risky sexual behavior. This paper examines the effects of the early twenty-first century copper boom on risky sexual behavior in Zambian copper mining cities. The results suggest that the copper boom substantially reduced rates of transactional sex and multiple partnerships in copper mining cities. These effects were partly concentrated among young adults and copper boom induced in-migration to mining cities appears to have contributed to these reductions. Copyright © 2012. Published by Elsevier B.V.

THE IMPACT OF HEXAMETAPHOSPHATE ON COPPER CORROSION AND RELEASE

EPA Science Inventory

In 1991, U.S. Environmental Protection Agency (U.S. EPA) promulgated the Lead and Copper Rule, which established a copper action level of 1.3 mg/L in a 1-liter, first-draw sample collected from the consumer’s tap (Federal Register, 1991a, 1991b, 1992). The rule was established d...

Overexpression of amyloid precursor protein increases copper content in HEK293 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suazo, Miriam; Hodar, Christian; Morgan, Carlos

2009-05-15

Amyloid precursor protein (APP) is a transmembrane glycoprotein widely expressed in mammalian tissues and plays a central role in Alzheimer's disease. However, its physiological function remains elusive. Cu{sup 2+} binding and reduction activities have been described in the extracellular APP135-156 region, which might be relevant for cellular copper uptake and homeostasis. Here, we assessed Cu{sup 2+} reduction and {sup 64}Cu uptake in two human HEK293 cell lines overexpressing APP. Our results indicate that Cu{sup 2+} reduction increased and cells accumulated larger levels of copper, maintaining cell viability at supra-physiological levels of Cu{sup 2+} ions. Moreover, wild-type cells exposed to bothmore » Cu{sup 2+} ions and APP135-155 synthetic peptides increased copper reduction and uptake. Complementation of function studies in human APP751 transformed Fre1 defective Saccharomyces cerevisiae cells rescued low Cu{sup 2+} reductase activity and increased {sup 64}Cu uptake. We conclude that Cu{sup 2+} reduction activity of APP facilitates copper uptake and may represent an early step in cellular copper homeostasis.« less

Spatial patterns of chemical contamination (metals, PAHs, PCBs, PCDDs/PCDFS) in sediments of a non-industrialized but densely populated coral atoll/small island state (Bermuda).

PubMed

Jones, Ross J

2011-06-01

There is a recognized dearth of standard environmental quality data in the wider Caribbean area, especially on coral atolls/small island states. Extensive surveys of sediment contamination (n=109 samples) in Bermuda revealed a wide spectrum of environmental quality. Zinc and especially copper levels were elevated at some locations, associated with boating (antifouling paints and boatyard discharges). Mercury contamination was surprisingly prevalent, with total levels as high as 12mg kg(-1)DW, although methyl mercury levels were quite low. PAH, PCB and PCDD/PCDF contamination was detected a several hotspots associated with road run-off, a marine landfill, and a former US Naval annexe. NOAA sediment quality guidelines were exceeded at several locations, indicating biological effects are possible, or at some locations probable. Overall, and despite lack of industrialization, anthropogenic chemicals in sediments of the atoll presented a risk to benthic biodiversity at a number of hotspots suggesting a need for sediment management strategies. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of valerian consumption during pregnancy on cortical volume and the levels of zinc and copper in the brain tissue of mouse fetus.

PubMed

Mahmoudian, Alireza; Rajaei, Ziba; Haghir, Hossein; Banihashemian, Shahaboldin; Hami, Javad

2012-04-01

The aim of the present study was to determine the effects of valerian (Valeriana officinalis) consumption in pregnancy on cortical volume and the levels of zinc and copper, two essential elements that affect brain development and function, in the brain tissues of mouse fetuses. Pregnant female mice were treated with either saline or 1.2 g/kg body weight valerian extract intraperitoneally daily on gestation days (GD) 7 to 17. On GD 20, mice were sacrificed and their fetuses were collected. Fetal brains were dissected, weighed and processed for histological analysis. The volume of cerebral cortex was estimated by the Cavalieri principle. The levels of zinc and copper in the brain tissues were measured by atomic absorption spectroscopy. The results indicated that valerian consumption in pregnancy had no significant effect on brain weight, cerebral cortex volume and copper level in fetal brain. However,it significantly decreased the level of zinc in the brain (P<0.05). Using valerian during midgestation do not have an adverse effect on cerebral cortex; however,it caused a significant decrease in zinc level in the fetal brain. This suggests that valerian use should be limited during pregnancy.

Tyrosinase inhibition due to interaction of homocyst(e)ine with copper: the mechanism for reversible hypopigmentation in homocystinuria due to cystathionine beta-synthase deficiency.

PubMed

Reish, O; Townsend, D; Berry, S A; Tsai, M Y; King, R A

1995-07-01

Deficiency of cystathionine beta-synthase (CBS) is a genetic disorder of transsulfuration resulting in elevated plasma homocyst(e)ine and methionine and decreased cysteine. Affected patients have multisystem involvement, which may include light skin and hair. Reversible hypopigmentation in treated homocystinuric patients has been infrequently reported, and the mechanism is undefined. Two CBS-deficient homocystinuric patients manifested darkening of their hypopigmented hair following treatment that decreased plasma homocyst(e)ine. We hypothesized that homocyst(e)ine inhibits tyrosinase, the major pigment enzyme. The activity of tyrosinase extracted from pigmented human melanoma cells (MNT-1) that were grown in the presence of homocysteine was reduced in comparison to that extracted from cells grown without homocysteine. Copper sulfate restored homocyst(e)ine-inhibited tyrosinase activity when added to the culture cell media at a proportion of 1.25 mol of copper sulfate per 1 mol of DL-homocysteine. Holo-tyrosinase activity was inhibited by adding DL-homocysteine to the assay reaction mixture, and the addition of copper sulfate to the reaction mixture prevented this inhibition. Other tested compounds, L-cystine and betaine did not affect tyrosinase activity. Our data suggest that reversible hypopigmentation in homocystinuria is the result of tyrosinase inhibition by homocyst(e)ine and that the probable mechanism of this inhibition is the interaction of homocyst(e)ine with copper at the active site of tyrosinase.

Tyrosinase inhibition due to interaction of homocyst(e)ine with copper: the mechanism for reversible hypopigmentation in homocystinuria due to cystathionine beta-synthase deficiency.

PubMed Central

Reish, O; Townsend, D; Berry, S A; Tsai, M Y; King, R A

1995-01-01

Deficiency of cystathionine beta-synthase (CBS) is a genetic disorder of transsulfuration resulting in elevated plasma homocyst(e)ine and methionine and decreased cysteine. Affected patients have multisystem involvement, which may include light skin and hair. Reversible hypopigmentation in treated homocystinuric patients has been infrequently reported, and the mechanism is undefined. Two CBS-deficient homocystinuric patients manifested darkening of their hypopigmented hair following treatment that decreased plasma homocyst(e)ine. We hypothesized that homocyst(e)ine inhibits tyrosinase, the major pigment enzyme. The activity of tyrosinase extracted from pigmented human melanoma cells (MNT-1) that were grown in the presence of homocysteine was reduced in comparison to that extracted from cells grown without homocysteine. Copper sulfate restored homocyst(e)ine-inhibited tyrosinase activity when added to the culture cell media at a proportion of 1.25 mol of copper sulfate per 1 mol of DL-homocysteine. Holo-tyrosinase activity was inhibited by adding DL-homocysteine to the assay reaction mixture, and the addition of copper sulfate to the reaction mixture prevented this inhibition. Other tested compounds, L-cystine and betaine did not affect tyrosinase activity. Our data suggest that reversible hypopigmentation in homocystinuria is the result of tyrosinase inhibition by homocyst(e)ine and that the probable mechanism of this inhibition is the interaction of homocyst(e)ine with copper at the active site of tyrosinase. Images Figure 1 PMID:7611281

Systems biology approach in Chlamydomonas reveals connections between copper nutrition and multiple metabolic steps.

PubMed

Castruita, Madeli; Casero, David; Karpowicz, Steven J; Kropat, Janette; Vieler, Astrid; Hsieh, Scott I; Yan, Weihong; Cokus, Shawn; Loo, Joseph A; Benning, Christoph; Pellegrini, Matteo; Merchant, Sabeeha S

2011-04-01

In this work, we query the Chlamydomonas reinhardtii copper regulon at a whole-genome level. Our RNA-Seq data simulation and analysis pipeline validated a 2-fold cutoff and 10 RPKM (reads per kilobase of mappable length per million mapped reads) (~1 mRNA per cell) to reveal 63 CRR1 targets plus another 86 copper-responsive genes. Proteomic and immunoblot analyses captured 25% of the corresponding proteins, whose abundance was also dependent on copper nutrition, validating transcriptional regulation as a major control mechanism for copper signaling in Chlamydomonas. The impact of copper deficiency on the expression of several O₂-dependent enzymes included steps in lipid modification pathways. Quantitative lipid profiles indicated increased polyunsaturation of fatty acids on thylakoid membrane digalactosyldiglycerides, indicating a global impact of copper deficiency on the photosynthetic apparatus. Discovery of a putative plastid copper chaperone and a membrane protease in the thylakoid suggest a mechanism for blocking copper utilization in the chloroplast. We also found an example of copper sparing in the N assimilation pathway: the replacement of copper amine oxidase by a flavin-dependent backup enzyme. Forty percent of the targets are previously uncharacterized proteins, indicating considerable potential for new discovery in the biology of copper.

Hydrocarbon-fuel/copper combustion chamber liner compatibility, corrosion prevention, and refurbishment

NASA Technical Reports Server (NTRS)

Rosenberg, S. D.; Gage, M. L.; Homer, G. D.; Franklin, J. E.

1991-01-01

An evaluation is made of combustion product/combustion chamber compatibility in the case of a LOX/liquid hydrocarbon booster engine based on copper-alloy thrust chamber which is regeneratively cooled by the fuel. It is found that sulfur impurities in the fuel are the primary causes of copper corrosion, through formation of Cu2S; sulfur levels as low as 1 ppm can result in sufficiently severe copper corrosion to degrade cooling channel performance. This corrosion can be completely eliminated, however, through the incorporation of an electrodeposited gold coating on the copper cooling-channel walls.

Relation of serum γ-glutamyl transferase activity with copper in an adult population.

PubMed

Peng, You-Fan; Wang, Chun-Fang; Pan, Guo-Gang

2017-10-26

The aim of this study was to evaluate the relationship between serum γ-glutamyl transferase (γ-GGT) activity and serum copper in an adult population. We analyzed 281 adult subjects who regularly attended the physical examination center at the Affiliated Hospital of Youjiang Medical University for Nationalities. The demographic and laboratory data of the participants were divided into two groups according to the median of serum γ-GGT activity. Serum copper concentrations in individuals with higher γ-GGT levels were significantly increased compared with those with lower γ-GGT concentrations (9.9±2.41 vs. 11.2±3.36 μmol/L, p<0.001). There was a positive correlation between serum γ-GGT activity and copper in all eligible subjects (r=0.198, p=0.001). Further, serum γ-GGT maintained a positive correlation with serum copper in both males and females (r=0.322, p<0.001; r=0.230, p=0.010). The results of multiple linear regression analysis showed that serum γ-GGT maintained a significantly positive correlation with copper after adjusting for multiple potential confounders (b=0.464, p=0.001). This study suggests that serum γ-GGT activity is correlated with copper in the study population, indicating that serum γ-GGT may be a biomarker to evaluate serum copper levels in an adult population.

EXAMINATION OF THE OXIDATION PROTECTION OF ZINC COATINGS FORMED ON COPPER ALLOYS AND STEEL SUBSTRATES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Papazoglou, M.; Chaliampalias, D.; Vourlias, G.

2010-01-21

The exposure of metallic components at aggressive high temperature environments, usually limit their usage at similar application because they suffer from severe oxidation attack. Copper alloys are used in a wide range of high-quality indoor and outdoor applications, statue parts, art hardware, high strength and high thermal conductivity applications. On the other hand, steel is commonly used as mechanical part of industrial set outs or in the construction sector due to its high mechanical properties. The aim of the present work is the examination of the oxidation resistance of pack cementation zinc coatings deposited on copper, leaded brass and steelmore » substrates at elevated temperature conditions. Furthermore, an effort made to make a long-term evaluation of the coated samples durability. The oxidation results showed that bare substrates appear to have undergone severe damage comparing with the coated ones. Furthermore, the mass gain of the uncoated samples was higher than this of the zinc covered ones. Particularly zinc coated brass was found to be more resistant to oxidation conditions in which it was exposed as it has the lower mass gain as compared to the bare substrates and zinc coated copper. Zinc coated steel was also proved to be more resistive than the uncoated steel.« less

Trace-metal leaching from plumbing materials exposed to acidic ground water in three areas of the coastal plain of New Jersey

USGS Publications Warehouse

Kish, G.R.; Macy, J.A.; Mueller, R.T.

1987-01-01

The U.S. Geological Survey analyzed trace metal concentrations in tap water from domestic wells in newly constructed homes in Berkeley Township, Ocean County and Galloway Township, Atlantic County, N. J. The potable water distribution systems in all of the homes sampled are constructed primarily of copper with lead-based solder points. Home water treatment is used in Berkeley Township but not in Galloway Township. Tap water was collected after the water had been standing in the pipes overnight. In Berkeley, 6 to 11 samples exceeded both the U.S. Environmental Protection Agency 's primary drinking water regulation (DWR) for lead (50 microgram/L) and the secondary drinking water regulation (SDWR) for copper (1,000 microgram/L). In Galloway, 12 of 14 samples exceeded the DWR for lead and 13 of 14 exceeded the SDWR for copper. After collecting the standing-water samples, the water was left running for 15 minutes and a second sample was collected. None of the running-water samples exceeded the regulations for lead or copper. Available data suggest a correlation between the residence time of soft, acidic groundwater in new home plumbing systems and elevated trace-metal concentrations in drinking water derived from domestic wells within the New Jersey Coastal Plain. (USGS)

An Expanding Range of Functions for the Copper Chaperone/Antioxidant Protein Atox1

PubMed Central

Hatori, Yuta

2013-01-01

Abstract Significance: Antioxidant protein 1 (Atox1 in human cells) is a copper chaperone for the copper export pathway with an essential role in cellular copper distribution. In vitro, Atox1 binds and transfers copper to the copper-transporting ATPases, stimulating their catalytic activity. Inactivation of Atox1 in cells inhibits maturation of secreted cuproenzymes as well as copper export from cells. Recent Advances: Accumulating data suggest that cellular functions of Atox1 are not limited to its copper-trafficking role and may include storage of labile copper, modulation of transcription, and antioxidant defense. The conserved metal binding site of Atox1, CxGC, differs from the metal-binding sites of copper-transporting ATPases and has a physiologically relevant redox potential that equilibrates with the GSH:GSSG pair. Critical Issues: Tight relationship appears to exist between intracellular copper levels and glutathione (GSH) homeostasis. The biochemical properties of Atox1 place it at the intersection of cellular networks that regulate copper distribution and cellular redox balance. Mechanisms through which Atox1 facilitates copper export and contributes to oxidative defense are not fully understood. Future Directions: The current picture of cellular redox homeostasis and copper physiology will be enhanced by further mechanistic studies of functional interactions between the GSH:GSSG pair and copper-trafficking machinery. Antioxid. Redox Signal. 19, 945–957. PMID:23249252

Metallic copper corrosion rates, moisture content, and growth medium influence survival of copper-ion resistant bacteria

PubMed Central

Elguindi, Jutta; Moffitt, Stuart; Hasman, Henrik; Andrade, Cassandra; Raghavan, Srini; Rensing, Christopher

2013-01-01

The rapid killing of various bacteria in contact with metallic copper is thought to be influenced by influx of copper ions into the cells but the exact mechanism is not fully understood. This study showed that the kinetics of contact-killing of copper surfaces depended greatly on the amount of moisture present, copper content of alloys, type of medium used, and type of bacteria. We examined antibiotic- and copper-ion resistant strains of Escherichia coli and Enterococcus faecium isolated from pig farms following the use of copper sulfate as feed supplement. The results showed rapid killing of both copper-ion resistant E. coli and E. faecium strains when samples in rich medium were spread in a thin, moist layer on copper alloys with 85% or greater copper content. E. coli strains were rapidly killed under dry conditions while E. faecium strains were less affected. Electroplated copper surface corrosion rates were determined from electro-chemical polarization tests using the Stern-Geary method and revealed decreased corrosion rates with benzotriazole and thermal oxide coating. Copper-ion resistant E. coli and E. faecium cells suspended in 0.8% NaCl showed prolonged survival rates on electroplated copper surfaces with benzotriazole coating and thermal oxide coating compared to surfaces without anti-corrosion treatment. Control of surface corrosion affected the level of copper ion influx into bacterial cells which contributed directly to bacterial killing. PMID:21085951

Release of Micronized Copper Particles from Pressure ...

EPA Pesticide Factsheets

Micronized copper pressure treated lumber (PTL) has recently been introduced to the consumer market as a replacement for ionized copper PTL. The presence of particulate rather than aqueous copper raises concerns about the exposure of humans as well as the environment to the particles. Two common pathways of exposure, leaching during contact with water and transfer during physical contact, were investigated to gage potential human and environmental risk during intended use of the product. Characterization, leaching tests, and wipe tests were conducted on two representative formulations of micronized copper PTL (micronized copper azole or MCA) to quantify the levels of copper present in the treated material and the amount of copper released during use as well as to determine the form (particle or ion) of the copper after it was released. Additionally, an ionized copper pressure treated wood (alkaline copper azole or ACA) was tested for comparison. The characterization showed that copper carbonate is the primary particle form in the MCA treated wood, but other forms are also present, particularly in the MCA-1 formulation, which contained a large amount of organically complexed copper. Microscopy showed that MCA-1 contained particles roughly half the size of MCA-2. The leaching results indicate that mostly (> ~95%) ionic copper is released from the MCA wood and that the particulate copper that was released is attached to cellulose and not free in solution. A sma

Metal endowment reflected in chemical composition of silicates and sulfides of mineralized porphyry copper systems, Urumieh-Dokhtar magmatic arc, Iran

NASA Astrophysics Data System (ADS)

Zarasvandi, Alireza; Rezaei, Mohsen; Raith, Johann G.; Pourkaseb, Houshang; Asadi, Sina; Saed, Madineh; Lentz, David R.

2018-02-01

The present work attempts to discriminate between the geochemical features of magmatic-hydrothermal systems involved in the early stages of mineralization in high grade versus low grade porphyry copper systems, using chemical compositions of silicate and sulfide minerals (i.e., plagioclase, biotite, pyrite and chalcopyrite). The data indicate that magmatic plagioclase in all of the porphyry copper systems studied here has high An% and Al content with a significant trend of evolution toward AlAl3SiO8 and □Si4O8 endmembers, providing insight into the high melt water contents of the parental magmas. Comparably, excess Al and An% in the high grade deposits appears to be higher than that of selected low grade deposits, representing a direct link between the amounts of exsolving hydrothermal fluids and the potential of metal endowment in porphyry copper deposits (PCDs). Also, higher Al contents accompanied by elevated An% are linked to the increasing intensity of disruptive alteration (phyllic) in feldspars from the high grade deposits. As calculated from biotite compositions, chloride contents are higher in the exsolving hydrothermal fluids that contributed to the early mineralization stages of highly mineralized porphyry systems. However, as evidenced by scattered and elevated log (fH2O)/(fHF) and log (fH2O)/(fHCl) values, chloride contents recorded in biotite could be influenced by post potassic fluids. Geothermometry of biotite associated with the onset of sulfide mineralization indicates that there is a trend of increasing temperature from high grade to low grade porphyry systems. Significantly, this is coupled with a sharp change in copper content of pyrite assemblages precipitated at the early stages of mineralization such that Cu decreased with increasing temperature. Based on EMPA and detailed WDS elemental mapping, trace elements do not exhibit complex compositional zoning or solid solution in the sulfide structure. Nevertheless, significant amounts of Cu and Au are contained in pyrite assemblages as micro- to nano-sized inclusions, especially in the high grade fertile porphyry deposits. However, unexpectedly high concentrations of Te, Se, and Re may be associated with early stage of sulfide mineralization, especially when there is no epithermal lithocap. This may highlight the significance of trace metals partitioning in the sulfides formed at the early stages of mineralization in PCDs.

Intracellular Copper Does Not Catalyze the Formation of Oxidative DNA Damage in Escherichia coli▿

PubMed Central

Macomber, Lee; Rensing, Christopher; Imlay, James A.

2007-01-01

Because copper catalyzes the conversion of H2O2 to hydroxyl radicals in vitro, it has been proposed that oxidative DNA damage may be an important component of copper toxicity. Elimination of the copper export genes, copA, cueO, and cusCFBA, rendered Escherichia coli sensitive to growth inhibition by copper and provided forcing circumstances in which this hypothesis could be tested. When the cells were grown in medium supplemented with copper, the intracellular copper content increased 20-fold. However, the copper-loaded mutants were actually less sensitive to killing by H2O2 than cells grown without copper supplementation. The kinetics of cell death showed that excessive intracellular copper eliminated iron-mediated oxidative killing without contributing a copper-mediated component. Measurements of mutagenesis and quantitative PCR analysis confirmed that copper decreased the rate at which H2O2 damaged DNA. Electron paramagnetic resonance (EPR) spin trapping showed that the copper-dependent H2O2 resistance was not caused by inhibition of the Fenton reaction, for copper-supplemented cells exhibited substantial hydroxyl radical formation. However, copper EPR spectroscopy suggested that the majority of H2O2-oxidizable copper is located in the periplasm; therefore, most of the copper-mediated hydroxyl radical formation occurs in this compartment and away from the DNA. Indeed, while E. coli responds to H2O2 stress by inducing iron sequestration proteins, H2O2-stressed cells do not induce proteins that control copper levels. These observations do not explain how copper suppresses iron-mediated damage. However, it is clear that copper does not catalyze significant oxidative DNA damage in vivo; therefore, copper toxicity must occur by a different mechanism. PMID:17189367

The effects of CaEDTA injection on lead, zinc, copper and ALAD in erythrocyte, plasma and urine in lead-exposed workers: a 24-h observation.

PubMed

Aono, H; Araki, S

1984-01-01

To evaluate the effects of calcium disodium ethylenediamine tetraacetate (CaEDTA) on the concentrations of lead, zinc and copper in plasma, erythrocyte and urine, and the delta-aminolevulinic acid dehydratase (ALAD) activity in erythrocyte, we administered CaEDTA in 1-h intravenous infusion to ten male gun metal founders with blood-lead concentration of 39 to 64 micrograms/dl (mean 49 micrograms/dl). We found that the plasma concentration of lead, following a rapid rise within the first 3 h, fell temporarily to the level significantly lower than the initial level 19 h after start of the infusion. The plasma concentration of zinc fell to the minimal level 5 h after the infusion; and the erythrocyte concentration of zinc and the ALAD activity concurrently rose to the maximal level 5 h after the infusion. By contrast, no significant alteration was observed in the concentrations of copper in plasma and erythrocyte. The maximal level of urinary metal excretion was attained during the period between 1 and 2 h after start of CaEDTA infusion for lead; within 2 h for zinc; and between 2 and 4 h for copper. The urinary metal excretion returned to the initial level 14 to 24 h after infusion for zinc and copper; but lead excretion was still higher than the initial level during this period. The difference in the kinetics of the three metals following CaEDTA injection is discussed in the light of these findings.

Testicular toxicity and sperm quality following copper exposure in Wistar albino rats: ameliorative potentials of L-carnitine.

PubMed

Khushboo, Maurya; Murthy, Meesala Krishna; Devi, Maibam Sunita; Sanjeev, Sanasam; Ibrahim, Kalibulla Syed; Kumar, Nachimuthu Senthil; Roy, Vikas Kumar; Gurusubramanian, Guruswami

2018-01-01

Copper is a persistent toxic and bio-accumulative heavy metal of global concern. Continuous exposure of copper compounds of different origin is the most common form of copper poisoning and in turn adversely altering testis morphology and function and affecting sperm quality. L-carnitine has a vital role in the spermatogenesis, physiology of sperm, sperm production and quality. This study was designed to examine whether the detrimental effects of long-term copper consumption on sperm quality and testis function of Wistar albino rat could be prevented by L-carnitine therapy. The parameters included were sperm quality (concentration, viability, motility, and morphology), histopathology, serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT), serum urea, serum creatinine, serum testosterone and testis antioxidant enzyme levels (superoxide dismutase and glutathione-S-transferase), and biomarkers of oxidative stress (lipid peroxidation and expression of heat shock protein 70 in testis). Three-month-old male Wistar rats (n = 30) were divided into six groups as group 1 (G1, 0.9% saline control), group 2 (G2, CuSO4 200 mg/kg dissolved in 0.9% saline water), groups 3 and 4 (G3 and G4, L-carnitine 50 and 100 mg/kg dissolved in 0.9% saline water, respectively), and groups 5 and 6 (G5 and G6, CuSO 4 200 mg/kg plus L-carnitine, 50 and 100 mg/kg dissolved in 0.9% saline water, respectively). Doses of copper (200 mg/kg) and L-carnitine (50 and 100 mg/kg) alone and in combinations along with untreated control were administered orally for 30 days. The following morphological, physiological, and biochemical alterations were observed due to chronic exposure of copper (200 mg/kg) to rats in comparison with the untreated control: (1) generation of oxidative stress through rise in testis lipid peroxidation (12.21 vs 3.5 nmol MDA equivalents/mg protein) and upregulation of heat shock protein (overexpression of HSP70 in testis), (2) liver and kidney dysfunction [elevation in serum ALT (81.65 vs 48.08 IU/L), AST (156.82 vs 88.25 IU/L), ALP (230.54 vs 148.16 IU/L), urea (12.65 vs 7.45 mmol/L), and creatinine (80.61 vs 48.25 μmol/L) levels], (3) significant decrease in body (99.64 vs 106.09 g) and organ weights (liver-3.48 vs 4.99 g; kidney-429.29 vs 474.78 mg; testes-0.58 vs 0.96 g), (4) imbalance in hormonal and antioxidant enzyme concentrations [significant decline in serum testosterone (0.778 vs 3.226 ng/mL), superoxide dismutase (3.07 vs 8.55 μmol/mg protein), and glutathione-S-transferase (59.28 vs 115.58 nmol/mg protein) levels], (5) severe alterations in the testis histomorphology [sloughed cells (90.65%, score 4 vs 15.65%, score 1), vacuolization (85.95%, score 4 vs 11.45%, score 1), cellular debris along with degenerative characteristics, accentuated germ cell depletion in the seminiferous epithelium, severe damage of spermatogonia and Sertoli cells (73.56%, score 3 vs 0%, score 1)], (6) suppression of spermatogenic process [hypospermatogenesis (low Jhonsen testicular biopsy score 4 vs 9.5), decrease in tubules size (283.75 vs 321.25 μm in diameter), and no. of germ cells (81.8 vs 148.7/100 tubules), Leydig cells (5.2 vs 36.65/100 tubules), and Sertoli cells (8.1 vs 13.5/100 tubules)], (7) sperm transit time was shorter in caput and cauda and ensued in incomplete spermatogenic process and formation of immature sperm leading to infertility, (8) sperm quality was affected significantly [decreased daily sperm production (13.21 vs 26.9 × 10 6 sperms/mL), sperm count (96.12 vs 154.25 × 10 6 /g), sperm viability (26.88 vs 91.65%), and sperm motility (38.48 vs 64.36%)], and (9) increase of head (32.82 vs 2.01%) and tail (14.85 vs 0.14%) morphologic abnormalities and DNA fragmentation index (88.37 vs 11.11%). Oxidative stress and their related events appear to be a potential mechanism involved in copper testicular toxicity and L-carnitine supplementation significantly modulated the possible adverse effects of copper on seminiferous tubules damage, testes function, spermatogenesis, and sperm quality. It was validated that the use of L-carnitine at doses of 50 and 100 mg/kg protects against copper-induced testicular tissue damage and acts as a therapeutic agent for copper heavy metal toxicity.

Copper Regulates Cyclic AMP-Dependent Lipolysis

PubMed Central

Krishnamoorthy, Lakshmi; Cotruvo, Joseph A.; Chan, Jefferson; Kaluarachchi, Harini; Muchenditsi, Abigael; Pendyala, Venkata S.; Jia, Shang; Aron, Allegra T.; Ackerman, Cheri M.; Vander Wal, Mark N.; Guan, Timothy; Smaga, Lukas P.; Farhi, Samouil L.; New, Elizabeth J.; Lutsenko, Svetlana; Chang, Christopher J.

2016-01-01

Cell signaling relies extensively on dynamic pools of redox-inactive metal ions such as sodium, potassium, calcium, and zinc, but their redox-active transition metal counterparts such as copper and iron have been studied primarily as static enzyme cofactors. Here we report that copper is an endogenous regulator of lipolysis, the breakdown of fat, which is an essential process in maintaining the body's weight and energy stores. Utilizing a murine model of genetic copper misregulation, in combination with pharmacological alterations in copper status and imaging studies in a 3T3-L1 white adipocyte model, we demonstrate that copper regulates lipolysis at the level of the second messenger, cyclic AMP (cAMP), by altering the activity of the cAMP-degrading phosphodiesterase PDE3B. Biochemical studies of the copper-PDE3B interaction establish copper-dependent inhibition of enzyme activity and identify a key conserved cysteine residue within a PDE3-specific loop that is essential for the observed copper-dependent lipolytic phenotype. PMID:27272565

Controlled copper ion release from phosphate-based glasses improves human umbilical vein endothelial cell survival in a reduced nutrient environment.

PubMed

Stähli, Christoph; Muja, Naser; Nazhat, Showan N

2013-02-01

The success of tissue engineering is dependent on rapid scaffold vascularization after engraftment. Copper ions are well known to be angiogenic but exhibit cytotoxicity at elevated doses. The high sensitivity to copper concentration underlines the need of a controlled release mechanism. This study investigated the effect of copper ions released from phosphate-based glasses (PGs) on human umbilical vein endothelial cells (HUVECs) under standard growth conditions (SGC), as well as in a reduced nutrient environment (RNE) with decreased bovine serum and growth factor concentrations to approximate conditions in the core of large volume scaffolds where nutrient diffusion is limited. Initially, HUVECs were exposed to a range of CuCl(2) concentrations in order to identify an optimal response in terms of their metabolism, viability, and apoptotic activity. Under SGC, HUVEC metabolic activity and viability were reduced in a dose-dependent manner in the presence of 0.44-12 ppm Cu(2+). In contrast, HUVEC death induced by the RNE was delayed by an optimal dose of 4 ppm Cu(2+), which was associated with a down-regulation of apoptosis as evidenced by caspase-3/7 activity. Copper ion release from soluble PGs of the formulation 50P(2)O(5)-30CaO-(20-x)Na(2)O-xCuO [mol%] (x=0, 1, 5 and 10) demonstrated a controllable increase with CuO content. The presence of 4 ppm copper ions released from the 10% CuO PG composition reproduced the delay in HUVEC death in the RNE, suggesting the potential of these materials to extend survival of transplanted endothelial cells in large volume scaffolds.

Effects of acidic recharge on groundwater at the St. Kevin Gulch site, Leadville, Colorado

USGS Publications Warehouse

Paschke, S.S.; Harrison, W.J.; Walton-Day, K.

2001-01-01

The acid rock drainage-affected stream of St. Kevin Gulch recharges the Quaternary sand and gravel aquifer of Tennessee Park, near Leadville, Colorado, lowering pH and contributing iron, cadmium, copper, zinc and sulphate to the ground-water system. Dissolved metal mobility is controlled by the seasonal spring runoff as well as oxidation/reduction (redox) reactions in the aquifer. Oxidizing conditions occur in the unconfined portions of the aquifer whilst sulphate-reducing conditions are found down gradient where semi-confined groundwater flow occurs beneath a natural wetland. Iron-reducing conditions occur in the transition from unconfined to semi-confined groundwater flow. Dissolved iron concentrations are low to not detectable in the alluvial fan recharge zone and increase in a down gradient direction. The effects of low-pH, metal-rich recharge are pronounced during low-flow in the fall when there is a defined area of low pH groundwater with elevated concentrations of dissolved zinc, cadmium, copper and sulphate adjacent to St. Kevin Gulch. Dissolved metal and sulphate concentrations in the recharge zone are diluted during spring runoff, although the maximum concentrations of dissolved zinc, cadmium, copper and sulphate occur at selected down gradient locations during high flow. Dissolved zinc, cadmium and copper concentrations are low to not detectable, whereas dissolved iron concentrations are greatest, in groundwater samples from the sulphate-reducing zone. Attenuation of zinc, cadmium and copper beneath the wetland suggests sulphide mineral precipitation is occurring in the semi-confined aquifer, in agreement with previous site investigations and saturation index calculations. Adsorption of dissolved zinc, cadmium and copper onto iron hydroxides is a minor attenuation process due to the low pH of the groundwater system.

Estimation of Mineral and Trace Element Profile in Bubaline Milk Affected with Subclinical Mastitis.

PubMed

Singh, Mahavir; Yadav, Poonam; Sharma, Anshu; Garg, V K; Mittal, Dinesh

2017-04-01

The milk samples from buffaloes of Murrah breed at mid lactation stage, reared at an organised dairy farm, were screened for subclinical mastitis based on bacteriological examination and somatic cell count following International Dairy Federation criteria. Milk samples from subclinical mastitis infected and healthy buffaloes were analysed to evaluate physicochemical alterations in terms of protein, fat, pH, electrical conductivity, chloride, minerals (sodium, potassium and calcium) and trace elements (iron, zinc, copper and selenium). In the present study, protein, fat, zinc, iron, calcium and selenium content was significantly lower (P < 0.001), while pH and electrical conductivity were significantly higher in mastitic milk as compared to normal milk. Concentration of electrolytes mainly sodium and chloride significantly increased with higher somatic cell count in mastitic milk and to maintain osmolality; potassium levels decreased proportionately. Correlation matrix revealed significantly positive interdependences of somatic cell count with pH, electrical conductivity, sodium and chloride. However, protein, fat, calcium and potassium were correlated negatively with elevated somatic cell count in mastitic milk. It is concluded that udder infections resulting in elevated somatic cells may alter the mineral and trace element profile of milk, and magnitude of changes may have diagnostic and prognostic value.

Laboratory evolution of copper tolerant yeast strains

PubMed Central

2012-01-01

Background Yeast strains endowed with robustness towards copper and/or enriched in intracellular Cu might find application in biotechnology processes, among others in the production of functional foods. Moreover, they can contribute to the study of human diseases related to impairments of copper metabolism. In this study, we investigated the molecular and physiological factors that confer copper tolerance to strains of baker's yeasts. Results We characterized the effects elicited in natural strains of Candida humilis and Saccharomyces cerevisiae by the exposure to copper in the culture broth. We observed that, whereas the growth of Saccharomyces cells was inhibited already at low Cu concentration, C. humilis was naturally robust and tolerated up to 1 g · L-1 CuSO4 in the medium. This resistant strain accumulated over 7 mg of Cu per gram of biomass and escaped severe oxidative stress thanks to high constitutive levels of superoxide dismutase and catalase. Both yeasts were then "evolved" to obtain hyper-resistant cells able to proliferate in high copper medium. While in S. cerevisiae the evolution of robustness towards Cu was paralleled by the increase of antioxidative enzymes, these same activities decreased in evolved hyper-resistant Candida cells. We also characterized in some detail changes in the profile of copper binding proteins, that appeared to be modified by evolution but, again, in a different way in the two yeasts. Conclusions Following evolution, both Candida and Saccharomyces cells were able to proliferate up to 2.5 g · L-1 CuSO4 and to accumulate high amounts of intracellular copper. The comparison of yeasts differing in their robustness, allowed highlighting physiological and molecular determinants of natural and acquired copper tolerance. We observed that different mechanisms contribute to confer metal tolerance: the control of copper uptake, changes in the levels of enzymes involved in oxidative stress response and changes in the copper-binding proteome. However, copper elicits different physiological and molecular reactions in yeasts with different backgrounds. PMID:22214286

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tishina, E.A.; Bel'kevich, P.I.; Churshukov, E.S.

This article reports on an investigation of the protective properties of resinous substances that are waste materials in the production of deresined wax. The protective properties of the resins extracted by BR-2 naphtha at 20/sup 0/C, 0/sup 0/C, and 5/sup 0/C, and also the ethanol-soluble and ethanol-insoluble components of these resins are examined. The results indicate that the peat wax resins do not show any corrosivity with respect to copper. At elevated temperatures, the resins are as good as the commercial additive Akor-1 in protective efficiency, and their alcohol-soluble components are better than the Akor-1. It is concluded that themore » good compatibility of the resins with mineral oils and their high level of protection make them suitable for use in liquid preservative formulations for the temporary corrosion protection of metal items.« less

Toxicity and deficiency of copper in Elsholtzia splendens affect photosynthesis biophysics, pigments and metal accumulation.

PubMed

Peng, Hongyun; Kroneck, Peter M H; Küpper, Hendrik

2013-06-18

Elsholtzia splendens is a copper-tolerant plant species growing on copper deposits in China. Spatially and spectrally resolved kinetics of in vivo absorbance and chlorophyll fluorescence in mesophyll of E. splendens were used to investigate the copper-induced stress from deficiency and toxicity as well as the acclimation to excess copper stress. The plants were cultivated in nutrient solutions containing either Fe(III)-EDTA or Fe(III)-EDDHA. Copper toxicity affected light-acclimated electron flow much stronger than nonphotochemical quenching (NPQ) or dark-acclimated photochemical efficiency of PSIIRC (Fv/Fm). It also changed spectrally resolved Chl fluorescence kinetics, in particular by strengthening the short-wavelength (<700 nm) part of NPQ altering light harvesting complex II (LHCII) aggregation. Copper toxicity reduced iron accumulation, decreased Chls and carotenoids in leaves. During acclimation to copper toxicity, leaf copper decreased but leaf iron increased, with photosynthetic activity and pigments recovering to normal levels. Copper tolerance in E. splendens was inducible; acclimation seems be related to homeostasis of copper and iron in E. splendens. Copper deficiency appeared at 10 mg copper per kg leaf DW, leading to reduced growth and decreased photosynthetic parameters (F0, Fv/Fm, ΦPSII). The importance of these results for evaluating responses of phytoremediation plants to stress in their environment is discussed.

Distribution of trace metals at Hopewell Furnace National Historic Site, Berks and Chester Counties, Pennsylvania

USGS Publications Warehouse

Sloto, Ronald A.; Reif, Andrew G.

2011-01-01

Hopewell Furnace, located approximately 50 miles northwest of Philadelphia, was a cold-blast, charcoal iron furnace that operated for 113 years (1771 to 1883). The purpose of this study by the U.S. Geological Survey, in cooperation with the National Park Service, was to determine the distribution of trace metals released to the environment from an historical iron smelter at Hopewell Furnace National Historic Site (NHS). Hopewell Furnace used iron ore from local mines that contained abundant magnetite and accessory sulfide minerals enriched in arsenic, cobalt, copper, and other metals. Ore, slag, cast iron furnace products, soil, groundwater, stream base flow, streambed sediment, and benthic macroinvertebrates were sampled for this study. Soil samples analyzed in the laboratory had concentrations of trace metals low enough to meet Pennsylvania Department of Environmental Protection standards for non-residential use. Groundwater samples from the supply well met U.S. Environmental Protection Agency drinking-water regulations. Concentrations of metals in surface-water base flow at the five stream sampling sites were below continuous concentration criteria for protection of aquatic organisms. Concentrations of metals in sediment at the five stream sites were below probable effects level guidelines for protection of aquatic organisms except for copper at site HF-3. Arsenic, copper, lead, zinc, and possibly cobalt were incorporated into the cast iron produced by Hopewell Furnace. Manganese was concentrated in slag along with iron, nickel, and zinc. The soil near the furnace has elevated concentrations of chromium, copper, iron, lead, and zinc compared to background soil concentrations. Concentrations of toxic elements were not present at concentrations of concern in water, soil, or stream sediments, despite being elevated in ore, slag, and cast iron furnace products. The base-flow surface-water samples indicated good overall quality. The five sampled sites generally had low concentrations of nutrients and major ions but had elevated concentrations of iron, manganese, and strontium when compared to sites sampled in adjacent watersheds. The background site on Baptism Creek generally had the lowest concentrations and yields of constituents. Low concentrations of nutrients and major ions at all five sites indicate that measured concentrations can be attributed to general land use and geology and not to point sources. Streambed-sediment sampling results indicated higher concentrations of all metals except nickel at sites on French Creek compared to the background site on Baptism Creek. Concentrations of aluminum, cadmium, and nickel were highest in sediment from the sampling site upstream from Hopewell Furnace. The highest concentrations of arsenic, boron, cobalt, copper, iron, lead, manganese, mercury, and zinc were detected at the site just below Hopewell Furnace, which indicates that the source of these metals may be in Hopewell Furnace NHS. The invertebrate community at the background site on Baptism Creek was dominated by pollution sensitive taxa indicating a healthy, diverse benthic-macroinvertebrate community. Benthic-macroinvertebrate communities at sampling sites on French Creek indicated disturbed communities when compared to the background site on Baptism Creek and that the overall stream quality immediately above and below Hopewell Furnace NHS is degraded. The benthic-macroinvertebrate communities were dominated by pollution-tolerant taxa, and taxa were less diverse than at the background site. Habitat conditions at the upstream site on French Creek were good but were degraded at downstream sites on French Creek. The major habitat issues at these sites were related to a lack of stable substrate, erosion, and deposition. Water quality and streambed-sediment quality do not indicate that the degraded benthic-macroinvertebrate communities are the result of poor water quality. Habitat conditions (erosion and sedimentation) and physical alterations (water temperature) from the outfall of Hopewell Lake are the most likely causes of the impaired communities.

Incorporation of copper nanoparticles into paper for point-of-use water purification

PubMed Central

Smith, James A.

2014-01-01

As a cost-effective alternative to silver nanoparticles, we have investigated the use of copper nanoparticles in paper filters for point-of-use water purification. This work reports an environmentally benign method for the direct in situ preparation of copper nanoparticles (CuNPs) in paper by reducing sorbed copper ions with ascorbic acid. Copper nanoparticles were quickly formed in less than 10 minutes and were well distributed on the paper fiber surfaces. Paper sheets were characterized by x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, and atomic absorption spectroscopy. Antibacterial activity of the CuNP sheets was assessed for by passing Escherichia coli bacteria suspensions through the papers. The effluent was analyzed for viable bacteria and copper release. The CuNP papers with higher copper content showed a high bacteria reduction of log 8.8 for E. coli. The paper sheets containing copper nanoparticles were effective in inactivating the test bacteria as they passed through the paper. The copper levels released in the effluent water were below the recommended limit for copper in drinking water (1 ppm). PMID:25014431

Copper Is a Host Effector Mobilized to Urine during Urinary Tract Infection To Impair Bacterial Colonization

PubMed Central

Hyre, Amanda N.; Kavanagh, Kylie; Kock, Nancy D.; Donati, George L.

2016-01-01

ABSTRACT Urinary tract infection (UTI) is a major global infectious disease affecting millions of people annually. Human urinary copper (Cu) content is elevated during UTI caused by uropathogenic Escherichia coli (UPEC). UPEC upregulates the expression of Cu efflux genes during clinical UTI in patients as an adaptive response to host-derived Cu. Whether Cu is mobilized to urine as a host response to UTI and its role in protection against UTI remain unresolved. To address these questions, we tested the hypothesis that Cu is a host effector mobilized to urine during UTI to limit bacterial growth. Our results reveal that Cu is mobilized to urine during UTI caused by the major uropathogens Proteus mirabilis and Klebsiella pneumoniae, in addition to UPEC, in humans. Ceruloplasmin, a Cu-containing ferroxidase, is found at higher levels in UTI urine than in healthy control urine and serves as the molecular source of urinary Cu during UTI. Our results demonstrate that ceruloplasmin decreases the bioavailability of iron in urine by a transferrin-dependent mechanism. Experimental UTI with UPEC in nonhuman primates recapitulates the increased urinary Cu content observed during clinical UTI. Furthermore, Cu-deficient mice are highly colonized by UPEC, indicating that Cu is involved in the limiting of bacterial growth within the urinary tract. Collectively, our results indicate that Cu is a host effector that is involved in protection against pathogen colonization of the urinary tract. Because urinary Cu levels are amenable to modulation, augmentation of the Cu-based host defense against UTI represents a novel approach to limiting bacterial colonization during UTI. PMID:28031261

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leite, Carlos Eduardo, E-mail: carlos.leite@pucrs.br; Programa de Pós-Graduação em Medicina: Ciências Médicas, Universidade Federal do Rio Grande do Sul, Porto Alegre, CEP 90035-003; Maboni, Lucas de Oliveira

The use of zebrafish (Danio rerio) is increasing as an intermediate preclinical model, to prioritize drug candidates for mammalian testing. As the immune system of the zebrafish is quite similar to that of mammals, models of inflammation are being developed for the screening of new drugs. The characterization of these models is crucial for studies that seek for mechanisms of action and specific pharmacological targets. It is well known that copper is a metal that induces damage and cell migration to hair cells of lateral line of zebrafish. Extracellular nucleotides/nucleosides, as ATP and adenosine (ADO), act as endogenous signaling moleculesmore » during tissue damage by exerting effects on inflammatory and immune responses. The present study aimed to characterize the inflammatory status, and to investigate the involvement of the purinergic system in copper-induced inflammation in zebrafish larvae. Fishes of 7 days post-fertilization were exposed to 10 μM of copper for a period of 24 h. The grade of oxidative stress, inflammatory status, copper uptake, the activity and the gene expression of the enzymes responsible for controlling the levels of nucleotides and adenosine were evaluated. Due to the copper accumulation in zebrafish larvae tissues, the damage and oxidative stress were exacerbated over time, resulting in an inflammatory process involving IL-1β, TNF-α, COX-2 and PGE{sub 2}. Within the purinergic system, the mechanisms that control the ADO levels were the most involved, mainly the reactions performed by the isoenzyme ADA 2. In conclusion, our data shed new lights on the mechanisms related to copper-induced inflammation in zebrafish larvae. - Graphical abstract: This scheme provides a chronological proposition for the biochemical events induced by copper in zebrafish larvae. The dashed line shows the absorption of copper over the exposure time. After 1 h of exposure to copper, the release of PGE{sub 2} occurs, followed by an increase of MPO (as a consequence of neutrophil migration), increased expression of genes involved in inflammatory events (IL-1β and TNF-α) and, reduction of the anti-inflammatory cytokine IL-10 at 4 h. At 24 h, the copper concentration is found highly increased, what is coincident with oxidative stress. Regarding the purinergic system, it is possible to observe an inhibition of ecto-5′-NT and ADA, with the consequent increase of AMP and ADA, respectively, at 24 h. The expression of enzyme-related genes shows a decrease in the expression of ecto-5′-NT and variable expressions of ADA subfamily enzymes. - Highlights: • Copper led to increased oxidative stress, and decreased the antioxidants' defenses. • Copper induced time-related changes of IL-1β, TNF-α, IL-10 and PGE{sub 2} levels. • ADA activity controls the levels of adenosine in copper-induced inflammation. • ADA 2 is the main ADA subfamily involved. • The purinergic system seems to be involved in the resolution of inflammation.« less

Efficacy of copper borax preservative against wood decay

Treesearch

William Abbott; Bessie Woodward; Michael West

2001-01-01

In this study, a wood preservative containing active ingredients of 43.5% borax and 3.1% copper hydroxide was evaluated in soil-block tests in accordance with AWPA E10. Results suggested thatthe copper hydroxide was not contributing to fungal toxicity at preservative threshold levels. Thresholds determined for this preservative were very close to those previously...

Experimental and ab Initio Study of Catena(bis(μ2-iodo)-6-methylquinoline-copper(I)) under Pressure: Synthesis, Crystal Structure, Electronic, and Luminescence Properties.

PubMed

Aguirrechu-Comerón, Amagoia; Hernández-Molina, Rita; Rodríguez-Hernández, Plácida; Muñoz, Alfonso; Rodríguez-Mendoza, Ulises R; Lavín, Vı́ctor; Angel, Ross J; Gonzalez-Platas, Javier

2016-08-01

Copper(I) iodine compounds can exhibit interesting mechanochromic and thermochromic luminescent properties with important technological applications. We report the synthesis and structure determination by X-ray diffraction of a new polymeric staircase copper(I) iodine compound catena(bis(μ2-iodo)-6-methylquinoline-copper(I), [C10H9CuIN]. The structure is composed of isolated polymeric staircase chains of copper-iodine coordinated to organic ligands through Cu-N bonds. High pressure X-ray diffraction to 6.45 GPa shows that the material is soft, with a bulk modulus K0 = 10.2(2)GPa and a first derivative K'0 = 8.1(3), typical for organometallic compounds. The unit-cell compression is very anisotropic with the stiffest direction [302] arising from a combination of the stiff CuI ladders and the shear of the planar quinolone ligands over one another. Full structure refinements at elevated pressures show that pressures reduce the Cu···Cu distances in the compound. This effect is detected in luminescence spectra with the appearance of four sub-bands at 515, 600, 647, and 712 nm above 3.5 GPa. Red-shifts are observed, and they are tentatively associated with interactions between copper(I) ions due to the shortening of the Cu···Cu distances induced by pressure, below twice the van der Waals limit (2.8 Å). Additionally, ab initio simulations were performed, and they confirmed the structure and the results obtained experimentally for the equation of state. The simulation allowed the band structure and the electronic density of states of this copper(I) iodine complex to be determined. In particular, the band gap decreases slowly with pressure in a quadratic way with dEg/dP = -0.011 eV/GPa and d(2)Eg/dP(2) = 0.001 eV/GPa(2).

NA{sup +}, K{sup +}-ATPase, histopathological, and genetic responses of Corbicula fluminea to sediment-associated copper

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, S.

1995-12-31

Time-dependent responses to sediment-associated copper were studies at hierarchical levels of biological organization along an extreme concentration gradient (40 to 40,000 mg/kg total Cu). Laboratory and in situ estimates of molecular to tissue-level responses (Na/K-ATPase activity, DNA content, histopathology) were monitored in Corbicula fluminea (Asiatic clam), and compared with laboratory and field based survival of Corbicula and Elimia teres (an indigenous Gastropoda). Mollusc survival was, in turn, compared with effects on macrobenthic community composition along the stream/[Cu] gradient. Relationships between selected sediment characteristics and the bioavailability and toxicity of sediment associated copper were also investigated. Sediment-associated copper depressed Na/K-ATPase activitymore » and led to histopathological damage of renal and gill epithelia (vacuolization, degeneration), indicating that impaired ion regulation was an important mechanism of toxicity. Concurrent reductions in DNA content were believed to be secondary effects due to cell death, not an indication of genotoxicity. Sublethal responses were significantly correlated with survival in both species; however, while survival in situ was indicative of differences in community structure, laboratory-based survival was not. Copper levels in tissues were indicative of exposure, but were not significantly correlated with adverse effects. Copper levels in sediments, interstitial water, and overlying water varied independently of sediment characteristics except pH. Cu/AVS ratios were predictive of Corbicula and Elimia survival, but were not significantly related to differences in community structure. Instead, macrobenthic community structure was influenced by other sediment factors (grain size, Eh, pH).« less

High serum copper level is associated with an increased risk of preeclampsia in Asians: A meta-analysis.

PubMed

Song, Xingxing; Li, Bingrong; Li, Zongyao; Wang, Jiantao; Zhang, Dongfeng

2017-03-01

Epidemiological studies evaluating the associations between serum copper and ratios of Cu/Zn and the preeclampsia (PE) risk in Asian population have produced inconsistent results. Therefore, we conducted a meta-analysis to summarize the relationships. We hypothesize that higher serum copper and ratios of Cu/Zn may increase the PE risk. A systematic literature search was performed in PubMed, Web of Science, Embase, Chinese National Knowledge Infrastructure (CNKI), VIP (Database of Chinese Scientific and Technical Periodicals) and Wangfang databases for relevant studies up to November 2016. Pooled standardized mean difference (SMD) was calculated with random effects model. The results showed that PE patients had a higher serum copper level [SMD (95% CI): 1.05 (0.34, 1.77), Z=2.88, P for Z=0.004; I 2 =96.9%, P for I 2 <0.0001] compared with healthy pregnancy controls. In subgroup analyses, a higher serum copper level in PE patients was observed in case-control studies [SMD (95% CI): 1.39 (0.44, 2.34)]. No significant difference was found between PE patients and healthy pregnancy controls for ratios of Cu/Zn [(SMD (95% CI): 0.26 (-0.77, 1.29), Z=0.49, P for Z=0.625; I 2 =95.8%, P for I 2 <0.0001)]. In conclusion, our meta-analysis indicates that a higher serum copper level is associated with an increased risk of PE. Further studies are needed to confirm these results in future research. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of copper supplement on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture.

PubMed

Rodríguez, L Mato; Alatossava, T

2008-10-01

To determine the effects of supplemented copper (Cu2+) on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture. Thirteen strains belonging to Lactobacillus delbrueckii, Lactobacillus helveticus, Lactobacillus rhamnosus, Streptococcus thermophilus or Propionibacterium freudenreichii species were exposed to various copper concentrations in the proper growth medium at relevant growth temperatures, and the effects of supplemented copper on bacterial growth and cell viability were determined by optical density and pH measurements, also by platings. Among the species considered, L. delbrueckii was the most copper resistant and S. thermophilus the most sensitive to copper. Anaerobic conditions increased this sensitivity significantly. There was also a considerable amount of variation in copper resistance at strain level. Copper resistance is both a species- and strain-dependent property and may reflect variability in copper-binding capacities by cell wall components among species and strains. In addition, the chemical state of copper may be involved. This study revealed that copper resistance is a highly variable property among starter and adjunct strains, and this variability should be considered when strains are selected for Emmental cheese manufacture.

Textured carbon on copper: A novel surface with extremely low secondary electron emission characteristics

NASA Technical Reports Server (NTRS)

Curren, A. N.; Jensen, K. A.

1985-01-01

Experimentally determined values of true secondary electron emission and relative values of reflected primary electron yield for a range of primary electron beam energies and beam impingement angles are presented for a series of novel textured carbon surfaces on copper substrates. (All copper surfaces used in this study were oxygen-free, high-conductivity grade). The purpose of this investigation is to provide information necessary to develop high-efficiency multistage depressed collectors (MDC's) for microwave amplifier traveling-wave tubes (TWT's) for communications and aircraft applications. To attain the highest TWT signal quality and overall efficiency, the MDC electrode surface must have low secondary electron emission characteristics. While copper is the material most commonly used for MDC electrodes, it exhibits relatively high levels of secondary electron emission unless its surface is treated for emission control. The textured carbon surface on copper substrate described in this report is a particularly promising candidate for the MDC electrode application. Samples of textured carbon surfaces on copper substrates typical of three different levels of treatment are prepared and tested for this study. The materials are tested at primary electron beam energies of 200 to 2000 eV and at direct (0 deg) to near-grazing (85 deg) beam impingement angles. True secondary electron emission and relative reflected primary electron yield characteristics of the textured surfaces are compared with each other and with those of untreated copper. All the textured carbon surfaces on copper substrate tested exhibited sharply lower secondary electron emission characteristics than those of an untreated copper surface.

Serum zinc, copper and iron status of children with coeliac disease on three months of gluten-free diet with or without four weeks of zinc supplements: a randomised controlled trial.

PubMed

Negi, K; Kumar, R; Sharma, L; Datta, S P; Choudhury, M; Kumar, P

2018-04-01

Data about the effect of zinc supplementation with gluten-free diet on normalisation of plasma zinc, copper and iron in patients with coeliac disease are scanty. We evaluated the effect of zinc supplementation on serum zinc, copper and iron levels in patients with coeliac disease, by randomising 71 children newly diagnosed with coeliac disease into two groups: Group A = gluten-free diet (GFD); and Group B = gluten-free diet with zinc supplements (GFD +Zn). The rise in iron and zinc was significantly higher in the latter, but the mean rise of copper levels was slightly higher in the former, but the difference was not significant.

Assessment of tolerant sunfish populations (Lepomis sp.) inhabiting selenium-laden coal ash effluents. 3. Serum chemistry and fish health indicators.

PubMed

Lohner, T W; Reash, R J; Willet, V E; Fletcher, J

2001-11-01

Sunfish were collected from fly ash discharge-receiving streams to assess the possible effects of exposure to elevated selenium. Concentrations of selenium, copper, and arsenic were statistically higher in fish tissue (liver) samples from effluent-exposed fish than in reference fish. Several biomarkers were indicative of metal exposure and effect. Plasma protein levels and cholesterol levels were significantly lower in exposed fish, indicating nutritional stress. Ion levels (i.e., K) increased with exposure to ash pond metals, indicating possible gill damage. Fish from the receiving streams also had increased serum glucose and osmolality indicating possible acute stress due to sampling. Fish health assessments revealed a lower incidence of fin erosion, kidney discoloration, urolithiasis or nephrocalcinosis, liver discoloration, and parasites in exposed fish and a higher incidence of skin, eye, and gill aberrations. Condition factors of exposed fish were correlated with biomarker response and were the same as or lower than those of reference fish, but not related to selenium levels. Although several serum biochemical indicators differed between the ash pond-receiving stream and reference sites, pollutant exposure was apparently not sufficient to cause functional damage to critical organ systems.

The effects of low-level ionizing radiation and copper exposure on the incidence of antibiotic resistance in lentic biofilm bacteria.

PubMed

McArthur, J Vaun; Dicks, Christian A; Bryan, A Lawrence; Tuckfield, R Cary

2017-09-01

Environmental reservoirs of antibiotic resistant bacteria are poorly understood. Understanding how the environment selects for resistance traits in the absence of antibiotics is critical in developing strategies to mitigate this growing menace. Indirect or co-selection of resistance by environmental pollution has been shown to increase antibiotic resistance. However no attention has been given to the effects of low-level ionizing radiation or the interactions between radiation and heavy metals on the maintenance or selection for antibiotic resistance (AR) traits. Here we explore the effect of radiation and copper on antibiotic resistance. Bacteria were collected from biofilms in two ponds - one impacted by low-level radiocesium and the other an abandoned farm pond. Through laboratory controlled experiments we examined the effects of increasing concentrations of copper on the incidence of antibiotic resistance. Differences were detected in the resistance profiles of the controls from each pond. Low levels (0.01 mM) of copper sulfate increased resistance but 0.5 mM concentrations of copper sulfate depressed the AR response in both ponds. A similar pattern was observed for levels of multiple antibiotic resistance per isolate. The first principal component response of isolate exposure to multiple antibiotics showed significant differences among the six isolate treatment combinations. These differences were clearly visualized through a discriminant function analysis, which showed distinct antibiotic resistance response patterns based on the six treatment groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

Systems Biology Approach in Chlamydomonas Reveals Connections between Copper Nutrition and Multiple Metabolic Steps[C][W][OA

PubMed Central

Castruita, Madeli; Casero, David; Karpowicz, Steven J.; Kropat, Janette; Vieler, Astrid; Hsieh, Scott I.; Yan, Weihong; Cokus, Shawn; Loo, Joseph A.; Benning, Christoph; Pellegrini, Matteo; Merchant, Sabeeha S.

2011-01-01

In this work, we query the Chlamydomonas reinhardtii copper regulon at a whole-genome level. Our RNA-Seq data simulation and analysis pipeline validated a 2-fold cutoff and 10 RPKM (reads per kilobase of mappable length per million mapped reads) (~1 mRNA per cell) to reveal 63 CRR1 targets plus another 86 copper-responsive genes. Proteomic and immunoblot analyses captured 25% of the corresponding proteins, whose abundance was also dependent on copper nutrition, validating transcriptional regulation as a major control mechanism for copper signaling in Chlamydomonas. The impact of copper deficiency on the expression of several O2-dependent enzymes included steps in lipid modification pathways. Quantitative lipid profiles indicated increased polyunsaturation of fatty acids on thylakoid membrane digalactosyldiglycerides, indicating a global impact of copper deficiency on the photosynthetic apparatus. Discovery of a putative plastid copper chaperone and a membrane protease in the thylakoid suggest a mechanism for blocking copper utilization in the chloroplast. We also found an example of copper sparing in the N assimilation pathway: the replacement of copper amine oxidase by a flavin-dependent backup enzyme. Forty percent of the targets are previously uncharacterized proteins, indicating considerable potential for new discovery in the biology of copper. PMID:21498682

Effects of an aged copper contamination on distribution of earthworms, reproduction and cocoon hatchability.

PubMed

Mirmonsef, Hassan; Hornum, Hanne D; Jensen, John; Holmstrup, Martin

2017-01-01

Contaminated soil is a problem throughout the industrialized world, and a significant proportion of these sites are polluted with heavy metals such as copper. Ecological risk assessment of contaminated sites requires ecotoxicological studies with spiked soils as well as in-situ ecological observations. Here, we report laboratory and field assessment of copper toxicity for earthworms at a Danish site (Hygum) exclusively contaminated with an increasing gradient in copper from background to highly toxic levels (>1000mgkg -1 dry soil). More specifically, we report effects on field populations, body contents of copper, hatching of earthworm cocoons and reproduction of the common species Aporrectodea tuberculata. Abundance of earthworms and cocoons decreased significantly from about 400-150m -2 along the gradient as the soil copper concentration increased from ca. 50 to ca. 1000mgkg -1 . At lower concentrations, the population was dominated by endogeic species, whereas at high concentrations the population was dominated by epigeic species. At high copper contents the internal concentration of copper was in the range 100-160mgkg -1 dry tissue. Despite the high internal copper contents, hatchability of field collected cocoons was not impaired in any species. The EC50 reproduction value of A. tuberculata was about 220mg copper kg -1 dry soil in the first two exposure periods, but nearly doubled in the third period suggesting that an acclimation response had occurred. Also in the laboratory reproduction test, cocoon hatchability was not reduced, but rather slightly stimulated by copper. Based on these results we discuss the possibility that acute exposure in laboratory experiments is more detrimental than exposure in a field situation, perhaps because increased tolerance may be acquired through natural selection and genetic adaptation through increased use of defense mechanisms such as metallothioneins. Further, we discuss that the rather high tissue copper level of earthworms from the Hygum site may have smaller effects in these free-ranging worms than it would have in acute-exposure laboratory tests because the copper is more efficiently sequestered and detoxified in the field situation where populations have been exposed for many generations. Copyright © 2016 Elsevier Inc. All rights reserved.

Juvenile roach (Rutilus rutilus) increase their anaerobic metabolism in response to copper exposure in laboratory conditions.

PubMed

Maes, Virginie; Betoulle, Stéphane; Jaffal, Ali; Dedourge-Geffard, Odile; Delahaut, Laurence; Geffard, Alain; Palluel, Olivier; Sanchez, Wilfried; Paris-Palacios, Séverine; Vettier, Aurélie; David, Elise

2016-07-01

This study aims to determine the potential impairment of cell energy synthesis processes (glycolysis and respiratory chain pathways) by copper in juvenile roach at different regulation levels by using a multi-marker approach. Juvenile roach were exposed to 0, 10, 50, and 100 µg/L of copper for 7 days in laboratory conditions. The glycolysis pathway was assessed by measuring the relative expression levels of 4 genes encoding glycolysis enzymes. The respiratory chain was studied by assessing the electron transport system and cytochrome c oxidase gene expression. Muscle mitochondria ultrastructure was studied, and antioxidant responses were measured. Furthermore, the main energy reserves-carbohydrates, lipids, and proteins-were measured, and cellular energy was evaluated by measuring ATP, ADP, AMP and IMP concentrations. This study revealed a disturbance of the cell energy metabolism due to copper exposure, with a significant decrease in adenylate energy charge in roach exposed to 10 μg/L of copper after 1 day. Moreover, ATP concentrations significantly decreased in roach exposed to 10 μg/L of copper after 1 day. This significant decrease persisted in roach exposed to 50 µg/L of copper after 7 days. AMP concentrations increased in all contaminated fish after 1 day of exposure. In parallel, the relative expression of 3 genes encoding for glycolysis enzymes increased in all contaminated fish after 1 day of copper exposure. Focusing on the respiratory chain, cytochrome c oxidase gene expression also increased in all contaminated fish at the two time-points. The activity of the electron transport system was not disturbed by copper, except in roach exposed to 100 µg/L of copper after 1 day. Copper induced a metabolic stress. Juvenile roach seemed to respond to the ensuing high energy demand by increasing their anaerobic metabolism, but the energy produced by the anaerobic metabolism is unable to compensate for the stress induced by copper after 7 days. This multi-marker approach allows us to reach a greater understanding of the effects of copper on the physiological responses of juvenile roach.

Constitutive response of passivated copper films to thermal cycling

NASA Astrophysics Data System (ADS)

Shen, Y.-L.; Ramamurty, U.

2003-02-01

The thermomechanical behavior of passivated thin copper films is studied. Stresses in copper films of thickness ranging from 125 to 1000 nm, deposited on quartz or silicon substrates and passivated with silicon oxide, were measured using the curvature method. The thermal cycling spans a temperature range from -196 to 600 °C. The measured mechanical behavior was found to be rate insensitive within the heating/cooling rate range of 5-25 °C/min. It was observed that the passivated films do not exhibit a significant stress relaxation at elevated temperatures that is normally found in unpassivated films. Furthermore, a significant strain hardening during the course of thermal loading was noted. Simple continuum plasticity analyses show that the experimentally measured stress-temperature response can only be rationalized with a kinematic hardening model. Analytical procedures for extracting the constitutive properties of the films that were developed on the basis of such a model are presented. The initial yield strength is higher and tends to be less temperature dependent in thinner films. The strain hardening rate is found to increase with decreasing film thickness.

Irradiation effects in tungsten-copper laminate composite

DOE PAGES

Garrison, L. M.; Katoh, Yutai; Snead, Lance L.; ...

2016-09-19

Tungsten-copper laminate composite has shown promise as a structural plasma-facing component as compared to tungsten rod or plate. The present study evaluated the tungsten-copper composite after irradiation in the High Flux Isotope Reactor (HFIR) at temperatures of 410–780 °C and fast neutron fluences of 0.02–9.0 × 10 25 n/m 2, E > 0.1 MeV, 0.0039–1.76 displacements per atom (dpa) in tungsten. Tensile tests were performed on the composites, and the fracture surfaces were analyzed with scanning electron microscopy. Before irradiation, the tungsten layers had brittle cleavage failure, but the overall composite had 15.5% elongation at 22 °C. After only 0.0039more » dpa this was reduced to 7.7% elongation, and no ductility was observed after 0.2 dpa at all irradiation temperatures when tensile tested at 22 °C. In conclusion, tor elevated temperature tensile tests after irradiation, the composite only had ductile failure at temperatures where the tungsten was delaminating or ductile.« less

Process for recovering uranium

DOEpatents

MacWood, G. E.; Wilder, C. D.; Altman, D.

1959-03-24

A process useful in recovering uranium from deposits on stainless steel liner surfaces of calutrons is presented. The deposit is removed from the stainless steel surface by washing with aqueous nitric acid. The solution obtained containing uranium, chromium, nickel, copper, and iron is treated with an excess of ammonium hydroxide to precipitnte the uranium, iron, and chromium and convert the nickel and copper to soluble ammonio complexions. The precipitated material is removed, dried and treated with carbon tetrachloride at an elevated temperature of about 500 to 600 deg C to form a vapor mixture of UCl/ sub 4/, UCl/sub 5/, FeCl/sub 3/, and CrCl/sub 4/. The UCl/sub 4/ is separated from this vapor mixture by selective fractional condensation at a temperature of about 500 to 400 deg C.

PROCESS FOR RECOVERING URANIUM

DOEpatents

MacWood, G.E.; Wilder, C.D.; Altman, D.

1959-03-24

A process is described for recovering uranium from deposits on stainless steel liner surfaces of calutrons. The deposit is removed from the stainless steel surface by washing with aqueous nitric acid. The solution obtained containing uranium, chromium, nickels copper, and iron is treated with excess of ammonium hydroxide to precipitatc the uranium, irons and chromium and convert thc nickel and copper to soluble ammonia complexions. The precipitated material is removed, dried, and treated with carbon tetrachloride at an elevated temperature of about 500 to 600 deg C to form a vapor mixture of UCl/sub 4/, UCl/sub 5/, FeCl/ sub 3/, and CrCl/sub 4/. The UCl/sub 4/ is separated from this vapor mixture by selective fractional condensation at a temprrature of about 300 to400 deg C.

Benzoin Radicals as Reducing Agent for Synthesizing Ultrathin Copper Nanowires.

PubMed

Cui, Fan; Dou, Letian; Yang, Qin; Yu, Yi; Niu, Zhiqiang; Sun, Yuchun; Liu, Hao; Dehestani, Ahmad; Schierle-Arndt, Kerstin; Yang, Peidong

2017-03-01

In this work, we report a new, general synthetic approach that uses heat driven benzoin radicals to grow ultrathin copper nanowires with tunable diameters. This is the first time carbon organic radicals have been used as a reducing agent in metal nanowire synthesis. In-situ temperature dependent electron paramagnetic resonance (EPR) spectroscopic studies show that the active reducing agent is the free radicals produced by benzoins under elevated temperature. Furthermore, the reducing power of benzoin can be readily tuned by symmetrically decorating functional groups on the two benzene rings. When the aromatic rings are modified with electron donating (withdrawing) groups, the reducing power is promoted (suppressed). The controllable reactivity gives the carbon organic radical great potential as a versatile reducing agent that can be generalized in other metallic nanowire syntheses.

Effects of Copper Addition on Copper Resistance, Antibiotic Resistance Genes, and intl1 during Swine Manure Composting

PubMed Central

Yin, Yanan; Gu, Jie; Wang, Xiaojuan; Song, Wen; Zhang, Kaiyu; Sun, Wei; Zhang, Xin; Zhang, Yajun; Li, Haichao

2017-01-01

Copper is one of the most abundant heavy metals present in swine manure. In this study, a laboratory-scale aerobic composting system was amended with Cu at three levels (0, 200, and 2000 mg kg-1, i.e., control, Cu200, and Cu2000 treatments, respectively) to determine its effect on the fate of copper resistance genes [copper resistance genes (CRGs): pcoA, cusA, copA, and tcrB], antibiotic resistance genes [antibiotic resistance genes (ARGs): erm(A) and erm(B)], and intl1. The results showed that the absolute abundances of pcoA, tcrB, erm(A), erm(B), and intl1 were reduced, whereas those of copA and cusA increased after swine manure composting. Redundancy analysis showed that temperature significantly affected the variations in CRGs, ARGs, and intl1. The decreases in CRGs, ARGs, and intI1 were positively correlated with the exchangeable Cu levels. The bacterial community could be grouped according to the composting time under different treatments, where the high concentration of copper had a more persistent effect on the bacterial community. Network analysis determined that the co-occurrence of CRGs, ARGs, and intI1, and the bacterial community were the main contributors to the changes in CRGs, ARG, and intl1. Thus, temperature, copper, and changes in the bacterial community composition had important effects on the variations in CRGs, ARGs, and intl1 during manure composting in the presence of added copper. PMID:28316595

Subacute copper-deficiency myelopathy in a patient with occult celiac disease.

PubMed

Cavallieri, Francesco; Fini, Nicola; Contardi, Sara; Fiorini, Massimo; Corradini, Elena; Valzania, Franco

2017-07-01

Acquired copper deficiency represents a rare cause of progressive myelopathy presenting with sensory ataxia and spastic gait. The time interval from neurological symptoms onset to diagnosis of myelopathy ranges from 2 months to several years in almost all cases, mimicking the clinical course of subacute combined degeneration due to vitamin B12 deficiency. A 60-year-old man, without any gastrointestinal symptoms, developed over the course of one week rapidly progressive gait imbalance, tingling and numbness in his feet and ascending lower limb weakness. Spine magnetic resonance imaging revealed hyperintensity involving cervical and dorsal posterior columns of spinal cord. Blood analysis revealed undetectable serum copper levels, low serum ceruloplasmin and positive serum Immunoglobulin A anti-tissue transglutaminase. Upper gastrointestinal endoscopy was performed revealing duodenal villous atrophy consistent with a malabsorption pattern. A gluten-free diet in association with intravenous then oral copper supplementation prompted sustained normalization of serum copper levels and progressive clinical improvement. We report a rare case of myelopathy induced by copper deficiency secondary to undiagnosed celiac disease, peculiarly presenting with a subacute onset. This case expands the neurological presentation and clinical course of myelopathy due to acquired copper deficiency. We suggest investigation of copper deficiency in patients presenting with subacute or even acute sensory ataxia and spastic gait. Detection of hypocupremia in patients without a previous history of gastric surgery should lead to diagnostic testing for celiac disease even in the absence of any obvious gastrointestinal symptoms.

Nutritional and Metabolic Biomarkers in Autism Spectrum Disorders: An Exploratory Study

PubMed Central

Esparham, Anna E.; Smith, Teri; Belmont, John M.; Haden, Michael; Wagner, Leigh E.; Evans, Randall G.; Drisko, Jeanne A.

2015-01-01

Context Autism spectrum disorder (ASD) is currently on the rise, now affecting approximately 1 in 68 children in the United States according to a 2010 surveillance summary from the Centers for Disease Control and Prevention (CDC). This figure is an estimated increase of 78% from the figure in 2002. The CDC suggests that more investigation is needed to understand this astounding increase in autism in such a short period. Objective The aim of this pilot study was to determine whether a group of children with ASD exhibited similar variations in a broad array of potential correlates, including medical histories, symptoms, genetics, and multiple nutritional and metabolic biomarkers. Design This study was a retrospective, descriptive chart review. Setting The study took place at the University of Kansas Medical Center (KUMC). Participants Participants were 7 children with ASD who had sought treatment at the Integrative Medicine Clinic at the medical center. Results A majority of the children exhibited an elevated copper:zinc ratio and abnormal vitamin D levels. Children also demonstrated abnormal levels of the essential fatty acids: (1) α-linolenic acid (ALA)— C13:3W3, and (2) linoleic acid (LA)—C18:2W6; high levels of docosahexaenoic acid (DHA); and an elevated ω-6:ω-3 ratio. Three of 7 children demonstrated abnormal manganese levels. Children did not demonstrate elevated urine pyruvate or lactate but did have abnormal detoxification markers. Three of 7 patients demonstrated abnormalities in citric acid metabolites, bacterial metabolism, and fatty acid oxidation markers. A majority demonstrated elevated serum immunoglobulin G (IgG) antibodies to casein, egg whites, egg yolks, and peanuts. A majority had absent glutathione S-transferase (GSTM) at the 1p13.3 location, and 3 of 7 children were heterozygous for the glutathione S-transferase I105V (GSTP1). A majority also exhibited genetic polymorphism of the mitochondrial gene superoxide dismutase A16V (SOD2). Conclusions The findings from this small group of children with ASD points to the existence of nutritional, metabolic, and genetic correlates of ASD. These factors appear to be important potential abnormalities that warrant a case control study to evaluate their reliability and validity as markers of ASD. PMID:26770138

High copper level comulled and impregnated sulfur sorbent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bishop, K.C.

A porous sulfur sorbent is disclosed which has principal use in desulfurizing reformer feedstreams. The sorbent is prepared by peptizing alumina with acid and mulling the peptized alumina with a copper compound to form an extrudable dough. The dough is extruded, dried and impregnated with additional copper. The resulting sorbent has a higher capacity for adsorbing sulfur compounds than conventional prior art materials.

Copper homeostasis gene discovery in Drosophila melanogaster.

PubMed

Norgate, Melanie; Southon, Adam; Zou, Sige; Zhan, Ming; Sun, Yu; Batterham, Phil; Camakaris, James

2007-06-01

Recent studies have shown a high level of conservation between Drosophila melanogaster and mammalian copper homeostasis mechanisms. These studies have also demonstrated the efficiency with which this species can be used to characterize novel genes, at both the cellular and whole organism level. As a versatile and inexpensive model organism, Drosophila is also particularly useful for gene discovery applications and thus has the potential to be extremely useful in identifying novel copper homeostasis genes and putative disease genes. In order to assess the suitability of Drosophila for this purpose, three screening approaches have been investigated. These include an analysis of the global transcriptional response to copper in both adult flies and an embryonic cell line using DNA microarray analysis. Two mutagenesis-based screens were also utilized. Several candidate copper homeostasis genes have been identified through this work. In addition, the results of each screen were carefully analyzed to identify any factors influencing efficiency and sensitivity. These are discussed here with the aim of maximizing the efficiency of future screens and the most suitable approaches are outlined. Building on this information, there is great potential for the further use of Drosophila for copper homeostasis gene discovery.

Is Exposure to Macondo Oil Reflected in the Otolith Chemistry of Marsh-Resident Fish?

PubMed Central

López-Duarte, Paola C.; Fodrie, F. Joel; Jensen, Olaf P.; Whitehead, Andrew; Galvez, Fernando; Dubansky, Benjamin; Able, Kenneth W.

2016-01-01

Genomic and physiological responses in Gulf killifish (Fundulus grandis) in the northern Gulf of Mexico have confirmed oil exposure of resident marsh fish following the Macondo blowout in 2010. Using these same fish, we evaluated otolith microchemistry as a method for assessing oil exposure history. Laser-ablation inductively-coupled-plasma mass spectrometry was used to analyze the chemical composition of sagittal otoliths to assess whether a trace metal signature could be detected in the otoliths of F. grandis collected from a Macondo-oil impacted site in 2010, post-spill relative to pre-spill, as well as versus fish from areas not impacted by the spill. We found no evidence of increased concentrations of two elements associated with oil contamination (nickel and vanadium) in F. grandis otoliths regardless of Macondo oil exposure history. One potential explanation for this is that Macondo oil is relatively depleted of those metals compared to other crude oils globally. During and after the spill, however, elevated levels of barium, lead, and to a lesser degree, copper were detected in killifish otoliths at the oil-impacted collection site in coastal Louisiana. This may reflect oil contact or other environmental perturbations that occurred concomitant with oiling. For example, increases in barium in otoliths from oil-exposed fish followed (temporally) freshwater diversions in Louisiana in 2010. This implicates (but does not conclusively demonstrate) freshwater diversions from the Mississippi River (with previously recorded higher concentrations of lead and copper), designed to halt the ingress of oil, as a mechanism for elevated elemental uptake in otoliths of Louisiana marsh fishes. These results highlight the potentially complex and indirect effects of the Macondo oil spill and human responses to it on Gulf of Mexico ecosystems, and emphasize the need to consider the multiple stressors acting simultaneously on inshore fish communities. PMID:27682216

Geochemical signature of land-based activities in Caribbean coral surface samples

USGS Publications Warehouse

Prouty, N.G.; Hughen, K.A.; Carilli, J.

2008-01-01

Anthropogenic threats, such as increased sedimentation, agrochemical run-off, coastal development, tourism, and overfishing, are of great concern to the Mesoamerican Caribbean Reef System (MACR). Trace metals in corals can be used to quantify and monitor the impact of these land-based activities. Surface coral samples from the MACR were investigated for trace metal signatures resulting from relative differences in water quality. Samples were analyzed at three spatial scales (colony, reef, and regional) as part of a hierarchical multi-scale survey. A primary goal of the paper is to elucidate the extrapolation of information between fine-scale variation at the colony or reef scale and broad-scale patterns at the regional scale. Of the 18 metals measured, five yielded statistical differences at the colony and/or reef scale, suggesting fine-scale spatial heterogeneity not conducive to regional interpretation. Five metals yielded a statistical difference at the regional scale with an absence of a statistical difference at either the colony or reef scale. These metals are barium (Ba), manganese (Mn), chromium (Cr), copper (Cu), and antimony (Sb). The most robust geochemical indicators of land-based activities are coral Ba and Mn concentrations, which are elevated in samples from the southern region of the Gulf of Honduras relative to those from the Turneffe Islands. These findings are consistent with the occurrence of the most significant watersheds in the MACR from southern Belize to Honduras, which contribute sediment-laden freshwater to the coastal zone primarily as a result of human alteration to the landscape (e.g., deforestation and agricultural practices). Elevated levels of Cu and Sb were found in samples from Honduras and may be linked to industrial shipping activities where copper-antimony additives are commonly used in antifouling paints. Results from this study strongly demonstrate the impact of terrestrial runoff and anthropogenic activities on coastal water quality in the MACR. ?? 2008 Springer-Verlag.

[Biochemical protective mechanisms in the accumulation of heavy metals in organisms].

PubMed

Petukhov, A S; Petukhova, G A

At present due to the environmental contamination by heavy metals there is a great interest to investigate the processes of their both accumulation in plants and toxic effect on biochemical indices. Therefore the objective of this research was the analysis of the alteration of the system of antioxidant protection ofplants in conditions of soil contamination by copper and zinc. Research object were germinants of oat in amount of300 plants in each variant of the experiment. For the performance of the experiment, the sand was equally contaminated by sulfates of Cu and Zn in concentration of 2 MPC on its gross content in soil. The experiment lastedfor 2 weeks. For the implementation of the objective of research there was analyzed the contentof both Cu and Zn in plants exposed to soil contamination. Additionally there was performed an analysis of as the content of lipids peroxidation products, phenols and flavonoids; as well the activity ofperoxidase, catalase and photosynthetic system. Under the soil contamination by copper and zinc corresponding to 2 MPC the accumulation of heavy metals was established to be happening in plants. If compared copper accumulation was higher than zinc accumulation that can be explained by the high migration capability of zinc. Under combined impact of two metals there was revealed their antagonistic interaction. There was established an elevated content of lipids peroxidation products in cells as a sequence of the accumulation of heavy metals in plants. As a result of the elevation of the content of lipids peroxidation products there was revealed a raised activity ofphotosynthetic apparatus and antioxidant system (carotenoids, catalase and peroxidase) in the cell. The decrease of the content ofphenols and flavonoids is related with the usage of this system of antioxidant protection for the neutralization of lipids peroxidation processes.

Ligand-Doped Copper Oxo-hydroxide Nanoparticles are Effective Antimicrobials

NASA Astrophysics Data System (ADS)

Bastos, Carlos A. P.; Faria, Nuno; Ivask, Angela; Bondarenko, Olesja M.; Kahru, Anne; Powell, Jonathan

2018-04-01

Bacterial resistance to antimicrobial therapies is an increasing clinical problem. This is as true for topical applications as it is for systemic therapy. Topically, copper ions may be effective and cheap antimicrobials that act through multiple pathways thereby limiting opportunities to bacteria for resistance. However, the chemistry of copper does not lend itself to facile formulations that will readily release copper ions at biologically compatible pHs. Here, we have developed nanoparticulate copper hydroxide adipate tartrate (CHAT) as a cheap, safe, and readily synthesised material that should enable antimicrobial copper ion release in an infected wound environment. First, we synthesised CHAT and showed that this had disperse aquated particle sizes of 2-5 nm and a mean zeta potential of - 40 mV. Next, when diluted into bacterial medium, CHAT demonstrated similar efficacy to copper chloride against Escherichia coli and Staphylococcus aureus, with dose-dependent activity occurring mostly around 12.5-50 mg/L of copper. Indeed, at these levels, CHAT very rapidly dissolved and, as confirmed by a bacterial copper biosensor, showed identical intracellular loading to copper ions derived from copper chloride. However, when formulated at 250 mg/L in a topically applied matrix, namely hydroxyethyl cellulose, the benefit of CHAT over copper chloride was apparent. The former yielded rapid sustained release of copper within the bactericidal range, but the copper chloride, which formed insoluble precipitates at such concentration and pH, achieved a maximum release of 10 ± 7 mg/L copper by 24 h. We provide a practical formulation for topical copper-based antimicrobial therapy. Further studies, especially in vivo, are merited.

Boron-copper neutron absorbing material and method of preparation

DOEpatents

Wiencek, Thomas C.; Domagala, Robert F.; Thresh, Henry

1991-01-01

A composite, copper clad neutron absorbing material is comprised of copper powder and boron powder enriched with boron 10. The boron 10 content can reach over 30 percent by volume, permitting a very high level of neutron absorption. The copper clad product is also capable of being reduced to a thickness of 0.05 to 0.06 inches and curved to a radius of 2 to 3 inches, and can resist temperatures of 900.degree. C. A method of preparing the material includes the steps of compacting a boron-copper powder mixture and placing it in a copper cladding, restraining the clad assembly in a steel frame while it is hot rolled at 900.degree. C. with cross rolling, and removing the steel frame and further rolling the clad assembly at 650.degree. C. An additional sheet of copper can be soldered onto the clad assembly so that the finished sheet can be cold formed into curved shapes.