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1

Cadmium, mercury, iron, copper, manganese and zinc in the liver and kidney of the Icelandic lamb.  

PubMed

The purpose of this study was to evaluate the levels of cadmium, mercury, iron, copper, manganese and zinc in lamb liver and kidney from six areas in Iceland and to compare the results against aerial deposition data for the same elements obtained using moss as an indicator organism. The total number of samples was 96 for each organ. Cadmium was determined by graphite furnace atomic absorption spectrophotometry, mercury by cold-vapour atomic absorption, and iron, copper, manganese and zinc by inductively coupled plasma atomic emission spectrophotometry. Analysis of variance determined significance differences among means for areas, and Pearson's correlation coeffcients were calculated to study correlation among trace elements in liver and kidney. The mean fresh weight concentrations in lamb liver and kidney respectively were 0.045 and 0.058 mgkg(-1) for cadmium, 0.009 and 0.012 mgkg(-1) for mercury, 141 and 52.7 mgkg(-1) for iron, 28.1 and 2.89 mgkg(-1) for copper, 4.01 and 1.13 mgkg(-1) for manganese and 48.7 and 25.2 mgkg(-1) for zinc. Concentrations of cadmium, mercury and copper in the liver and kidney of the Icelandic lamb were low compared with data from other countries. Iron concentrations in the organs, however, were high. No sample exceeded 46% of the proposed maximum level for cadmium in organs for human consumption in the EC. Cadmium, mercury, iron and copper in the liver and kidney differed significantly between areas. Deposition of cadmium and copper in moss was not a usefull indicator in the evaluation of the susceptibility of the Icelandic lamb to accumulation of cadmium and copper. However, iron levels in Icelandic lamb liver showed the same pattern as results for iron from the moss study. The cadmium and mercury levels of organs from lambs grazing in the vicinity of Mount Hekla a few months after its eruption did not indicate a significant contamination from volcanic activity. PMID:11665737

Reykdal, O; Thorlacius, A

2001-11-01

2

Some effects of oral ingestion of cadmium on zinc, copper, and iron metabolism  

Microsoft Academic Search

Several biological effects that reflect the interaction of cadmium and zinc when cadium is ingested by rats are described. Data from several reports and investigations show that the ingestion of low levels of cadmium by rats can cause alteration of zinc metabolism in the liver, emphysema, reduced pulmonary function, depression of copper and iron metabolism in the rat fetus, growth

H. G. Petering; H. Choudhury; K. L. Stemmer

1979-01-01

3

Some effects of oral ingestion of cadmium on zinc, copper, and iron metabolism.  

PubMed Central

Data are presented to show that ingestion of cadmium chloride by rats at low levels leads to alteration of zinc metabolism in the liver, even though the formation of metallothionein is not evident. A dose-response relationship between amount of cadmium ingested and degree of perturbation of zinc metabolism in liver was found. Oral cadmium was shown to cause emphysema and reduce pulmonary function in male rats; the effect was less severe or delayed in onset if dietary zinc concentration was high. Interference with copper and iron metabolism was shown to occur in rats given low levels of cadmium orally. Depression of copper and iron metabolism of the rat fetus was found to occur when dams received very low doses of cadmium during gestation, even though very little cadmium passed the placental barrier. Images FIGURE 1. a FIGURE 1. b FIGURE 2. a FIGURE 2. b

Petering, H G; Choudhury, H; Stemmer, K L

1979-01-01

4

Some observations on the interaction of zinc, copper, and iron metabolism in lead and cadmium toxicity.  

PubMed Central

A brief review of the literature indicates that nutritional deficiencies have been shown to increase the absorption and toxicity of orally ingested lead and cadmium. Results from recent studies indicates that low level oral ingestion of cadmium and lead perturbs the metabolism of zinc, copper, and iron and that these changes may be the earliest manifestation of the toxicity of lead and cadmium. The significance of these findings reveals itself in two ways: namely, that toxicologic investigations of lead and cadmium, whether experimental or clinical, must be based on a definitive consideration of the nutritional status of animals or people, and, secondly, that the preventive role of nutrition, especially that of trace metal intakes, must be taken seriously when establishing measures for reducing, eliminating, or combatting the toxic effects of widespread exposure to lead and cadmium in humans.

Petering, H G

1978-01-01

5

Assimilation of zinc, cadmium, lead, copper, and iron by the spider Dysdera crocata, a predator of woodlice  

SciTech Connect

In this paper, an experiment is described on the assimilation of zinc, cadmium, lead, copper and iron by Dysdera crocata collected from a site in central Bristol. The spiders were fed on woodlice from their own site, and on woodlice from a site contaminated by a smelting works which contained much higher levels of zinc, cadmium and lead than the spiders would have been used to in their normal diet.

Hopkin, S.P.; Martin, M.H.

1985-02-01

6

Total and Suspended Cadmium, Cobalt, Copper, Iron, Lead, Manganese, Nickel, and Zinc in the Water Column of the Black Sea  

Microsoft Academic Search

\\u000a The trace metals cadmium, cobalt, copper, iron, manganese, nickel, lead and zinc were determined at eleven different stations\\u000a in the Black Sea, in November 1984. Sampling from the surface down to 2100 m was carried out. Suspended matter was collected\\u000a and analysed. It was found that elements which form strong sulphide complexes show significantly lower concentration in the\\u000a anoxic zone.

Conny Haraldsson; Stig Westerlund

7

The levels of cadmium, nickel, manganese lead, zinc, iron, tin, copper and arsenic in the brined canned Jordanian cheese.  

PubMed

The levels of cadmium, nickel, manganese, lead, zinc, iron, tin, copper and arsenic in fresh sheep's milk, white brined cheese preserved in glass jars and in tin containers and their corresponding brines, salt and tin plates were determined by atomic absorption spectrophotometry. The results have been compared with those reported in recent years. Although metal levels were comparable with other investigators' data, our data shows that white brined cheese picked-up metals from tin containers and from the naturally contaminated salt, on the contrary brined cheese in preserved glass jars showed lower levels of metals. We recommend a purified salt for brine preparation and glass jars for white cheese preservation in order to minimize cheese contamination with metals from tin cans and salt. PMID:8212904

Ereifej, K I; Gharaibeh, S H

1993-08-01

8

Inductively coupled plasma atomic fluorescence spectrometric determination of cadmium, copper, iron, lead, manganese and zinc  

USGS Publications Warehouse

An inductively coupled plasma atomic fluorescence spectrometric method is described for the determination of six elements in a variety of geological materials. Sixteen reference materials are analysed by this technique to demonstrate its use in geochemical exploration. Samples are decomposed with nitric, hydrofluoric and hydrochloric acids, and the residue dissolved in hydrochloric acid and diluted to volume. The elements are determined in two groups based on compatibility of instrument operating conditions and consideration of crustal abundance levels. Cadmium, Cu, Pb and Zn are determined as a group in the 50-ml sample solution under one set of instrument conditions with the use of scatter correction. Limitations of the scatter correction technique used with the fluorescence instrument are discussed. Iron and Mn are determined together using another set of instrumental conditions on a 1-50 dilution of the sample solution without the use of scatter correction. The ranges of concentration (??g g-1) of these elements in the sample that can be determined are: Cd, 0.3-500; Cu, 0.4-500; Fe, 85-250 000; Mn, 45-100 000; Pb, 5-10 000; and Zn, 0.4-300. The precision of the method is usually less than 5% relative standard deviation (RSD) over a wide concentration range and acceptable accuracy is shown by the agreement between values obtained and those recommended for the reference materials.

Sanzolone, R. F.

1986-01-01

9

Manganese, copper, zinc, iron, cadmium, mercury and lead in muscle meat, liver and kidneys of poultry, rabbit and sheep slaughtered in the northern part of Poland, 1987  

Microsoft Academic Search

Manganese, copper, zinc, iron, cadmium, mercury and lead concentrations have been determined in muscle meat, livers and kidneys of ducks, geese, chickens, hens, rabbits and sheep slaughtered in the northern part of Poland in 1987. The mean values obtained related to wet weight for muscle meat, livers and kidneys of animals were: 0.11–0.27, 0.73–3.3 and 0.90–1.9 mg\\/kg Mn; 0.52–7.3, 3.8–88

J. Falandysz

1991-01-01

10

Release of aluminum, arsenic, cadmium, chromium, copper, iron, lead, and zinc in a coal leachate, and their removal from solution undergoing neutralization  

SciTech Connect

Whole coal contains significant amounts of iron pyrite which is oxidized ultimately to ferric acid sulfate. As a result, trace elements are released from the coal and other minerals in potentially hazardous concentrations. The purpose of this research was to: (1) study the release and mobility of selected trace elements during the weathering of coal; (2) seek to understand factors controlling solubility of trace elements in a synthetic, acidic leachate undergoing gradual neutralization; and (3) develop a chemical thermodynamic computer model to predict the effects of dilution and neutralization of leachate on trace element mobility and speciation. Samples collected periodically from a slurry of whole ground coal in water were filtered and analyzed for dissolved sulfate (by ion chromatography), iron (by flame atomic absorption spectrophotometry), and Al, Zn, Cd, Cu, Cr, Pb, As, and Se (by graphite furnace AAS). Iron, copper, and probably arsenic tracked the production of sulfate, while aluminum, zinc, chromium, and cadmium concentrations were stable or rose slightly. A synthetic leachate of ferric sulfate and sulfuric acid was doped with trace levels of Al, Zn, Cu, Cd, Cr, Pb, As, and Se. Slow injection of sodium bicarbonate solution neutralized the stirred system, though hydrolysis of iron buffered the pH and 2.5.

Tatum, T.L.

1992-01-01

11

Cadmium-copper interaction: tissue accumulation and subcellular distribution of cadmium in mice after simultaneous administration of cadmium and copper  

SciTech Connect

In vivo cadmium with copper was investigated using mice exposed to various combinations of Cd and Cu concentrations in drinking water. Animals were sacrificed at 0, 3, 6, 9 and 12 wk and brain, liver, kidney and spleen digests analyzed for cadmium, copper, iron and zinc by flame or flameless atomic absorption spectrophotometry. Tissue Zn, Fe and Cu levels were not altered by Cu or Cd additions to drinking water. Although a dose related increase in Cd was observed in kidney and liver throughout the experiment, a significant decrease was observed in Cd concentrations of these 2 tissues when 100 ppM Cu was added to 5 ppM Cd in drinking water but not when Cd levels were increased to 25 ppM or when Cu was reduced to 25 ppM. In order to determine the intracellular location of the increased Cd in these tissues, nuclei, microsomes, mitochondria and soluble proteins were isolated from liver and analyzed for Cd and Cu. Cadmium levels in the soluble protein fraction of liver of animals administered 5 ppM Cd were approx. 3-fold greater than that for the same Cd dose when Cu was added. The same was the case for the low molecular weight fraction (TCA supernatant) of liver. At the same time, Cu increased in both the total soluble protein and low mol wt protein fractions of Cd exposed animals when Cu was added. These results suggest an in vivo replacement of Cu for Cd in induced metallothionein-like Cu and Cd binding proteins. Copper at relatively low levels may play an important role in the prevention of accumulation of Cd in liver and kidney; however, this interaction appears to be dependent on a specific Cd:Cu ratio of metal intake.

Bourcier, D.R.; Sharma, R.P.; Brinkerhoff, C.R.

1981-06-01

12

Levels of lead, cadmium, copper, iron, and zinc in deciduous teeth of children living in Irbid, Jordan by ICP-OES: some factors affecting their concentrations.  

PubMed

The aim of this study was to measure the concentrations of lead (Pb), cadmium (Cd), copper (Cu), iron (Fe), and zinc (Zn) in deciduous teeth from children living in Jordan and to investigate the affecting factors. Deciduous teeth samples (n = 320, without fillings) were collected from 5- to 12-year-old children and analyzed for Pb, Cd, Cu, Fe, and Zn using inductively coupled plasma-optical emission spectrometry. A questionnaire was used to gather information on each child, such as sex, age, tooth type (incisors, canines, and molars), tooth position within the mouth (upper or lower jaw), caries status, presence of amalgam fillings inside the mouth, type of drinking water (tap water, home purified water, and plant purified water), and zone of residence (close to or far from heavy traffic roads). The mean concentrations of Pb, Cd, Cu, Fe, and Zn were 30.26, 0.55, 6.23, 34.72, and 128.21 ?g/g, respectively. Our results indicate that there is a clear relation between the concentrations of the metals analyzed in this study and tooth type, tooth position within the mouth, caries status, presence of amalgam fillings inside the mouth, and type of drinking water. No significant differences in the concentrations of the five metals analyzed were observed due to sex. Our results also show that no significant difference among Pb, Cd, Cu, Fe, and Zn concentrations and age among the ages of 5-6, 7-8, 9-10, and 11-12, except for Pb, which decreases at age 11-12. PMID:22851195

Alomary, A; Al-Momani, I F; Obeidat, S M; Massadeh, A M

2013-04-01

13

Lead, mercury, cadmium, chromium, nickel, copper, zinc, calcium, iron, manganese and chromium (VI) levels in Nigeria and United States of America cement dust.  

PubMed

This study was aimed at investigating the relative abundance of heavy metals in cement dust from different cement dust factories in order to predict their possible roles in the severity of cement dust toxicity. The concentrations of total mercury (Hg), copper (Cu), chromium (Cr), cadmium (Cd), nickel (Ni), manganese (Mn), lead (Pb), iron (Fe) and chromium (VI) (Cr (VI)) levels in cement dust and clinker samples from Nigeria and cement dust sample from the United States of America (USA) were determined using graphite furnace atomic absorption (GFAAS), while Zn and Ca were measured by flame atomic absorption spectrophotometry (FAAS), and Cr (VI) by colorimetric method. Total Cu, Ni and Mn were significantly higher in cement dust sample from USA (p<0.05), also, both total Cr and Cr (VI) were 5.4-26 folds higher in USA cement dust compared with Nigeria cement dust or clinker (p<0.001). Total Cd was higher in both Nigeria cement dust and clinker (p<0.05 and p<0.001), respectively. Mercury was more in both Nigeria cement dust and clinker (p<0.05), while Pb was only significantly higher in clinker from Nigeria (p<0.001). These results show that cement dust contain mixture of metals that are known human carcinogens and also have been implicated in other debilitating health conditions. Additionally, it revealed that metal content concentrations are factory dependent. This study appears to indicate the need for additional human studies relating the toxicity of these metals and their health impacts on cement factory workers. PMID:23261125

Ogunbileje, J O; Sadagoparamanujam, V-M; Anetor, J I; Farombi, E O; Akinosun, O M; Okorodudu, A O

2013-03-01

14

Cloud point extraction of copper, lead, cadmium, and iron using 2,6-diamino-4-phenyl-1,3,5-triazine and nonionic surfactant, and their flame atomic absorption spectrometric determination in water and canned food samples.  

PubMed

A cloud point extraction procedure was optimized for the separation and preconcentration of lead(II), cadmium(II), copper(II), and iron(III) ions in various water and canned food samples. The metal ions formed complexes with 2,6-diamino-4-phenyl-1,3,5-triazine that were extracted by surfactant-rich phases in the nonionic surfactant Triton X-114. The surfactant-rich phase was diluted with 1 M HNO3 in methanol prior to its analysis by flame atomic absorption spectrometry. The parameters affecting the extraction efficiency of the proposed method, such as sample pH, complexing agent concentration, surfactant concentration, temperature, and incubation time, were optimized. LOD values based on three times the SD of the blank (3Sb) were 0.38, 0.48, 1.33, and 1.85 microg/L for cadmium(II), copper(II), lead(II), and iron(III) ions, respectively. The precision (RSD) of the method was in the 1.86-3.06% range (n=7). Validation of the procedure was carried out by analysis of National Institute of Standards and Technology Standard Reference Material (NIST-SRM) 1568a Rice Flour and GBW 07605 Tea. The method was applied to water and canned food samples for determination of metal ions. PMID:22970587

Citak, Demirhan; Tuzen, Mustafa

2012-01-01

15

ACUTE LETHALITY OF COPPER, CADMIUM, AND ZINC TO NORTHERN SQUAWFISH  

EPA Science Inventory

Flow-through acute toxicity tests on juvenile northern squawfish (Ptychocheilus oregonensis) were conducted with copper, cadmium, and zinc. The 96-hour median lethal concentrations were 18 micrograms/liter for copper, 1,104 micrograms/liter for cadmium, and 3,693 micrograms/liter...

16

Metabolic crossroads of iron and copper  

PubMed Central

Interactions between the essential dietary metals, iron and copper, have been known for many years. This review highlights recent advances in iron-copper interactions with a focus on tissues and cell types important for regulating whole-body iron and copper homeostasis. Cells that mediate dietary assimilation (enterocytes) and storage and distribution (hepatocytes) of iron and copper are considered, along with the principal users (erythroid cells) and recyclers of red cell iron (reticuloendothelial macrophages). Interactions between iron and copper in the brain are also discussed. Many unanswered questions regarding the role of these metals and their interactions in health and disease emerge from this synopsis, highlighting extensive future research opportunities.

Collins, James F; Prohaska, Joseph R; Knutson, Mitchell D

2013-01-01

17

Cadmium, zinc and copper in horse kidney metallothionein  

Microsoft Academic Search

Cadium, zinc, and copper were determined in kidney cortex samples and in protein fractions obtained from 20 normal Swedish horses. Cadmium concentrations in kidneys ranged from 0.01 to 1.46 mmole\\/kg. Zinc concentrations in kidneys increased with increasing cadmium concentrations. At low concentrations of cadmium the increase of zinc was almost equimolar with the increase in cadmium, but at higher concentrations

M. Nordberg; C. G. Elinder; B. Rahnster

1979-01-01

18

Parallels and contrasts between iron and copper metabolism.  

PubMed

This paper reviews the Second International Workshop on Iron and Copper Homeostasis, held in Pucón, Chile 10-13 November, 2001. We cover the presentations and papers published (this issue) with the intent to point out parallels, contrasts and cutting edge areas rather than to say something about every paper. Iron and copper metabolism have been intertwined for nearly 150 years and the interrelationship is growing with advances in understanding the role of ceruloplasmin as one example and the probable role of hephaestin as another. The transporter DMT1 (divalent metal transporter 1) clearly plays a major part in iron uptake and trafficking. Emerging evidence suggests that it plays a lesser role in manganese, cadmium and copper transport; but it is still being evaluated there. Yet another interaction may come from the IRE/IRP (Iron Responsive Element/Iron Regulatory Protein) story where a paradigmatic role in iron homeostasis is well established, but interaction with copper is only now emerging. Parallels include the nutrient status of both metals based on their utility for redox reactions as well as their toxicity primarily via reactive oxygen species. The workshop also revealed that alternate splicing of pre-mRNAs for iron and copper related proteins and tissue specific responses are additional similarities. Regulation of gene expression and excretion offered contrasts between the two metals. The workshop also considered a series of continuing and emerging issues. PMID:12572661

Garrick, Michael D; Núñez, Marco T; Olivares, Manuel; Harris, Edward D

2003-03-01

19

Mortality of copper cadmium alloy workers with special reference to lung cancer and non-malignant diseases of the respiratory system, 1946-92  

Microsoft Academic Search

OBJECTIVES--To identify and quantify any relations between occupational exposure to cadmium oxide fume and mortalities from lung cancer and from chronic non-malignant diseases of the respiratory system. METHODS--The mortality experience of 347 copper cadmium alloy workers, 624 workers employed in the vicinity of copper cadmium alloy work (vicinity workers), and 521 iron and brass foundry workers (all men) was investigated

T Sorahan; A Lister; M S Gilthorpe; J M Harrington

1995-01-01

20

Seasonal variability in cadmium, lead, copper, zinc and iron concentrations in the three major fish species, Oreochromis niloticus, Lates niloticus and Rastrineobola argentea in Winam Gulf, Lake Victoria: impact of wash-off into the lake.  

PubMed

Trace metals Cadmium (Cd), Lead (Pb), Copper (Cu), Zinc (Zn) and Iron (Fe) were analyzed in edible portions of three main finfish species namely Lates niloticus, Oreochromis niloticus and Rastrineobola argentea sampled from various beaches of Winam Gulf, Lake Victoria, Kenya, in order to determine any seasonal and site variations and the results showed significantly (p < 0.05) higher mean concentrations of Cd, Cu, Zn and Fe during the wet season compared to the dry season for all the three species indicating the impact of wash-off into the lake during the rainy periods. The overall mean concentrations of the heavy metals (in ?g/g dry weight) in all combined samples ranged from 0.17-0.40 (Cd), 0.47-2.53 (Pb), 2.13-8.74 (Cu), 28.9-409.3 (Zn) and 31.4-208.1 (Fe), respectively. It was found that consumption of Rastrineobola argentea can be a significant source of heavy metals especially Zn, to humans, compared with Lates niloticus and Oreochromis niloticus, if only the muscle parts of the latter two are consumed. PMID:22130608

Ongeri, David M K; Lalah, Joseph O; Wandiga, Shem O; Schramm, Karl-Werner; Michalke, Bernard

2012-02-01

21

Copper, silver, gold and zinc, cadmium, mercury oxides and hydroxides  

SciTech Connect

This book provides a compilation of solubility data published up to 1984, including evaluations of the data. Data are presented on the following: copper (I) oxide; copper (II) oxide and hydroxide; silver (I) oxide; silver (II) oxide; gold (III) hydroxide; zinc oxide and hydroxide; cadmium oxide and hydroxide; and mercury (II) oxide.

Dirkse, T.P.

1986-01-01

22

Effects of copper in high resistivity cadmium telluride  

NASA Astrophysics Data System (ADS)

In this paper, a large number of travelling heater method (THM) grown cadmium telluride crystals of high resistivity, having various concentrations of copper incorporated, have been investigated by PICTS and TSC techniques. The main results indicate that the levels identified in the 0.15-0.18 eV range can be explained by complexes including copper, rather than substitutional doping by this element, while the 0.35 eV level may result from active copper.

Biglari, B.; Samimi, M.; Hage-Ali, M.; Koebel, J. M.; Siffert, P.

1988-07-01

23

Copper, cadmium, and zinc concentrations in aquatic food chains from the upper sacramento river (california) and selected tributaries  

Microsoft Academic Search

Metals enter the Upper Sacramento River above Redding, California, primarily through Spring Creek, a tributary that receives acid-mine drainage from a US EPA Superfund site known locally as Iron Mountain Mine. Waterweed (Elodea canadensis) and aquatic insects (midge larvae, Chironomidae; and mayfly nymphs, Ephemeroptera) from the Sacramento River downstream from Spring Creek contained much higher concentrations of copper (Cu), cadmium

M. K. Saiki; D. T. Castleberry; T. W. May; B. A. Martin; F. N. Bullard

1995-01-01

24

The possible role of gradual accumulation of copper, cadmium, lead and iron and gradual depletion of zinc, magnesium, selenium, vitamins B2, B6, D, and E and essential fatty acids in multiple sclerosis.  

PubMed

Multiple sclerosis (MS) has a much higher incidence among caucasians that in any other race. Furthermore: females are much more susceptible than males and white females living in colder, wetter areas are much more susceptible than those living in warmer areas. On the other hand, menstruating women have increased copper (Cu) absorption and half-life, so they tend to accumulate more Cu than males. Moreover, rapidly growing girls have an increased demand for zinc (Zn), but their rapidly decreasing production of melatonin results in impaired Zn absorption, which is exacerbated by the high Cu levels. The low Zn levels result in deficient CuZnSuperoxide dismutase (CuZnSOD), which in turn leads to increased levels of superoxide. Menstruating females also often present with low magnesium (Mg) and vitamin B6 levels. Vitamin B6 moderates intracellular nitric oxide (NO) production and extracellular Mg is required for NO release from the cell, so that a deficiency of these nutrients results in increased NO production in the cell and reduced release from the cell. The trapped NO combines with superoxide to form peroxinitrite, an extremely powerful free radical that leads to the myelin damage of MS. Iron (Fe), molybdenum (Mo) and cadmium (Cd) accumulation also increase superoxide production. Which explains MS in males, who tend to accumulate Fe much faster and Cu much less rapidly than females. Since vitamin D is paramount for Mg absorption, the much reduced exposure to sunlight in the higher latitudes may account for the higher incidence in these areas. Moreover, vitamin B2 is a cofactor for xanthine oxidase, and its deficiency exacerbates the low levels of uric acid caused by high Cu levels, resulting in myelin degeneration. Finally Selenium (Se) and vitamin E prevent lipid peroxidation and EPA and DHA upregulate CuZnSOD. Therefore, supplementation with 100 mg MG, 25 mg vit B6, 10 mg vit B2, 15 mg Zn and 400 IU vit D and E, 100 microg Se, 180 mg EPA and 120 mg DHA per day between 14 and 16 years of age may prevent MS. PMID:10985916

Johnson, S

2000-09-01

25

[Effect of occupational lead exposure on various elements in the human blood. Effects on calcium, cadmium, iron, copper, magnesium, manganese and zinc levels in the human blood, erythrocytes and plasma in vivo].  

PubMed

The influence of occupational lead-exposure on calcium, magnesium and trace elements concentration in blood was investigated. We examined 96 lead-exposed persons and for comparison 46 persons without occupational lead exposure. The levels of lead, cadmium, calcium, iron, copper, magnesium, manganese and zinc were determined by atomic absorption spectrometry (AAS) in whole-blood, erythrocytes, as well as in plasma. The median of the lead-concentration in whole blood of the exposed group was 646 micrograms/l (+/- 66.6%-range: 449-814 micrograms/l). For the normal persons a median of 148 micrograms Pb/l (+/- 66.6%-range: 107-235 micrograms Pb/l) was calculated. In whole-blood, erythrocytes and plasma all element-concentrations of the non-exposed persons were in the normal ranges. The lead-exposed workers showed a higher manganese level. The other elements were found in normal values for this group. Increasing lead-concentrations in blood correlated with elevated levels of manganese and zinc in whole-blood, erythrocytes and plasma. The lead workers showed for the whole-blood manganese concentration a median of 14.2 micrograms/l (+/- 66.6%-range: 8.5-22.3 micrograms/l), for zinc a median of 6.3 mg/l (+/- 66.6%-range: 5.2-8.2 mg/l). Those levels were significantly higher than the levels of the non-exposed persons. For this group the median concentration of manganese was 4.8 micrograms/l (+/- 66.6%-range: 2.7-8.6 micrograms/l) and 5.7 mg/l (+/- 66.6%-range: 5.1-6.3 mg/l) for zinc respectively. For zinc positive correlation between blood lead levels and the levels of manganese and zinc in the three blood-compartments was found. An essential change of the element concentrations between erythrocytes and plasma, in the sense of a displacement from one blood-compartment to the other could not be detected. PMID:6475377

Truckenbrodt, R; Winter, L; Schaller, K H

1984-06-01

26

Cadmium, zinc, copper, and barium in foraminifera tests  

NASA Astrophysics Data System (ADS)

The concentrations of cadmium, zinc, copper and barium have been determined on 2-mg samples of single-species foraminifera populations. Cleaning techniques were tested using North Atlantic core tops, and followed by a detailed downcore study for the last 30,000 years in South Atlantic core V22-174. Raw foram tests cleaned by crushing followed by ultrasonic removal of fine-grained material, and dissolved in a pH 5.5 acetate buffer, contain appreciable amounts of trace elements associated with ferromanganese and alumino-silicate contaminants. A reductive/complexing cleaning treatment reduces ferromanganese contamination by 1-2 orders of magnitude. Acetate buffers at pH 5.5 complex iron and raise the solubility of ferromanganese oxides; these buffers are unsuitable for separating carbonate lattice-bound trace elements from the fraction associated with ferromanganese phases. Improved mechanical and ultrasonic reductive cleaning combined with a mild dissolution in distilled water under 1 atm. P CO 2 reduces contaminant levels another order of magnitude. The Cd and Zn concentrations (order 10 -8 mole Cd/mole Ca and 10 -5 mole Zn/mole Ca) of species with low surface area show an increase with decreasing isotopic temperatures. This increase is consistent with the increasing concentrations of these metals from low values in surface waters to higher values at depth. The variance of Cd and Zn over the last 30,000 years in the central South Atlantic is consistent with the probable variability of the dissolved trace elements at the calcification levels of the species analyzed. Cu and Ba are irreproducible and probably sensitive to residual contaminant phases. The trace element content of the tests differs from levels observed in a recent coprecipitation study. Foraminifera may be a significant vector in zinc cycling in the ocean.

Boyle, Edward A.

1981-03-01

27

Contamination of soil and vegetation near a zinc smelter by zinc, cadmium, copper, and lead  

Microsoft Academic Search

Metal oxide fumes escaping from two zinc smelters in Palmerton, Pa., have highly contaminated soil and vegetation with zinc, cadmium, copper, and lead. Within 1 km of the smelters, 135,000 parts per million (ppm) zinc, 1750 ppm cadmium, 2000 ppm copper, and 2000 ppm lead have been measured in the Oâ horizon. Approximately 90% of metals deposited on the soil

Marilyn J. Buchauer

1973-01-01

28

Localization and toxic effects of cadmium, copper, and uranium in Azolla  

Microsoft Academic Search

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis. The relative content of copper was eightfold higher in the root than in the shoot, suggesting low mobility of this metal in Azolla plant. Cadmium relative content in the shoot was similar

M. Sela; E. Tel-Or; E. Fritz; A. Huttermann

1988-01-01

29

Cadmium, copper and lead in aquatic macrophytes in Shoal Lake (Manitoba-Ontario)  

Microsoft Academic Search

Cadmium, copper and lead concentrations were surveyed in several species of submerged aquatic macrophytes in a Precambrian Shield Lake. Values were variable within each species and interspecific differences in metal concentration were not significant over the season as a whole. Cadmium concentration increased during the season in Potamogeton foliosus and Myriophyllum exalbescens, while copper and lead declined in P. foliosus.

Eva Pip

1990-01-01

30

A study of the stability of cadmium sulfide/copper sulfide and cadmium sulfide copper-indium-diselenide solar cells  

NASA Astrophysics Data System (ADS)

Groups of high efficiency cadmium sulfide/copper sulfide solar cells were exposed to combinations of stresses designed to isolate and accelerate intrinsic degradation mechanisms. Stresses included elevated temperature, illumination intensity, and cell loading conditions. All stress exposures and tests were conducted in a benign (high purity argon) atmosphere. Two primary intrinsic modes of degradation were identified: degradation of the open circuit voltage under continuous illumination and nonzero loading was found to be self recovering upon interruption of illumination or upon shorting or reverse biasing the cells. It was attributed to traps in the depletion region. Recovery from decay of light generated current was not spontaneous but could be partially accomplished by annealing in a reducing (hydrogen) environment. It was attributed to changes in the stoichiometry of the copper sulfide under the influence of electric fields and currents.

Noel, G.; Richard, N.; Gaines, G.

1984-08-01

31

Iron nutrition affects cadmium accumulation and toxicity in rice plants  

Microsoft Academic Search

The effect of iron (Fe) nutrition on cadmium (Cd) toxicity and accumulation in rice plants was studied using a hydroponic\\u000a system. The inhibitory effect of Cd on plant growth and chlorophyll content (SPAD value) was dependent on Fe level and the\\u000a genotype. Malondialdehyde (MDA) content in leaves and roots was not much affected by an increased Cd stress at 0.171 mg l?1

Guosheng Shao; Mingxue Chen; Weixia Wang; Renxiang Mou; Guoping Zhang

2007-01-01

32

Comparative Effects of Iron Deficiency Induced by Bleeding and a Low-Iron Diet on the Intestinal Absorptive Interactions of Iron, Cobalt, Manganese, Zinc, Lead and Cadmium1  

Microsoft Academic Search

Dietary iron deficiency enhances the absorption of iron, cobalt, manganese, zinc, cadmium and lead, whereas, iron deficiency due to bleeding in creases the absorption of iron, cobalt and perhaps manganese. To determine whether the response to bleeding is qualitatively different from that induced by dietary iron deficiency, metal absorption was studied in mice fed either a high- iron diet (120

PETER R. FLANAGAN; JAMES HAIST; LESLIE S. VALBERG

33

Influence of humic acids on the accumulation of copper and cadmium in Vallisneria spiralis L. from sediment  

Microsoft Academic Search

Physiological responses and metal accumulation in Vallisneria spiralis L. exposed to copper and cadmium contaminated sediment were examined at different metal concentrations and the influence\\u000a of humic acids on copper and cadmium accumulation was also studied. The plants of V. spiralis accumulated high amount of copper and cadmium. The maximum accumulation of 396 and 114 mg kg?1 DW copper were found in

Qian Wang; Zhu Li; Shuiping Cheng; Zhenbin Wu

2010-01-01

34

A rapid titrimetric determination of iron in copper concentrates and copper-bearing leach solutions.  

PubMed

A titrimetric method for the determination of iron(III) in the presence of copper is presented. This method involves the reduction of iron(III) with titanous sulphate followed by titration with dichromate. It has been successfully used for the determination of iron in both leach solutions and copper concentrates with a relative error of 1%. PMID:18962207

Sastri, V S

1978-01-01

35

Iron and copper release in drinking-water distribution systems.  

PubMed

A large-scale pilot study was carried out to evaluate the impacts of changes in water source and treatment process on iron and copper release in water distribution systems. Finished surface waters, groundwaters, and desalinated waters were produced with seven different treatment systems and supplied to 18 pipe distribution systems (PDSs). The major water treatment processes included lime softening, ferric sulfate coagulation, reverse osmosis, nanofiltration, and integrated membrane systems. PDSs were constructed from PVC, lined cast iron, unlined cast iron, and galvanized pipes. Copper pipe loops were set up for corrosion monitoring. Results showed that surface water after ferric sulfate coagulation had low alkalinity and high sulfates, and consequently caused the highest iron release. Finished groundwater treated by conventional method produced the lowest iron release but the highest copper release. The iron release of desalinated water was relatively high because of the water's high chloride level and low alkalinity. Both iron and copper release behaviors were influenced by temperature. PMID:17886579

Shi, Baoyou; Taylor, James S

2007-09-01

36

Adsorption of copper and cadmium onto soils: influence of organic matter  

SciTech Connect

The sorption of copper and cadmium by three arid-zone soils at low solution concentrations (i.e., <10 mmol m/sup -3/ for copper and <50 ..mu..mol m/sup -3/ for cadmium) was studied. Sorption isotherms in the present study were characterized by an S-curve which is defined by an initial slope that increases with metal concentration. Preliminary kinetic studies indicated that copper sorption reactions were completed within one hour. The sigmoidal character of the isotherm was found always to be greater for copper than for cadmium and greatest for the soil highest in soluble organic carbon. The distribution function, K/sub d/, for cadmium was a monotonically decreasing function of the amount of metal sorbed. Values of K/sub d/ first increased and then decreased with increasing amounts of copper sorbed. Although increasing sorbent concentration decreased copper sorption, the shape of the isotherm remained unchanged. A soil separate was prepared by successive extractions with a low electrolyte solution in order to remove most of the soluble organic matter. L-curve isotherms were observed for copper and cadmium sorption by the soil separate; the surface exhibited a high affinity for the metals relative to aqueous solution. The addition of a commercially prepared fulvic acid to the soil separate reproduced an S-curve for copper sorption. Likewise, addition of fulvic acid to the unamended soils increased the sigmoidal character of the copper isotherms. A kinetic study suggested that either fulvic acid was not sorbed by the soil separate within the time period of experiment (24 hours) or that it was readily desorbed by copper. Copper was readily desorbed by fulvic acid at concentrations that are found in the soil environment. It was proposed that soluble organic ligands can form nonsorbing, soluble complexes with copper and cadmium.

LeClaire, J.P.

1985-01-01

37

Copper and nickel partitioning in iron meteorites  

NASA Astrophysics Data System (ADS)

Trace element analyses using proton induced X-ray emission and synchrotron X-ray fluorescence have been made on metal and troilite from nine iron meteorites representing five geochemical groups. Nickel and copper distribution coefficients D (troilite/metal) vary by factors of 600 and 20, respectively, correlate positively with kamacite bandwidth and correlate negatively with bulk nickel content. Meteorites with bulk Ni of less than 10 percent have Cu-enriched troilite while those with Ni greater than 10 percent have Cu-depleted troilite. Since magmatic evolution and partial melting will produce Cu-enriched troilite only, the observation of Cu-depleted troilite in Ni-rich meteorites is evidence for subsolidus reequilibration, a process which reduces D(Cu) by transfer of Cu to exsolving metal. Elemental redistribution may have played an important role in establishing the present chemical trends in iron meteorites.

Sutton, S. R.; Delaney, J. S.; Smith, J. V.; Prinz, M.

1987-10-01

38

Yeast, a model organism for iron and copper metabolism studies  

Microsoft Academic Search

Virtually all organisms on earth depend on transition metals for survival. Iron and copper are particularly important because they participate in vital electron transfer reactions, and are thus cofactors of many metabolic enzymes. Their ability to transfer electrons also render them toxic when present in excess. Disturbances of iron and copper steady-state levels can have profound effects on cellular metabolism,

Jeane De Freitas; Henri Wintz; J Hyoun Kim; Helen Poynton; Tama Fox; Chris Vulpe

2003-01-01

39

Polyamine metabolism in sunflower plants under long-term cadmium or copper stress  

Microsoft Academic Search

Summary.  The effect of different doses of cadmium and copper was studied in relation to growth and polyamine (Pas) metabolism in shoots\\u000a of sunflower plants. Cadmium accumulated to higher levels than copper and shoot length was reduced by 0.5 and 1?mM Cd, but\\u000a only by 1?mM Cu. At 1?mM of Cd or Cu, Put content increased 270% and 160% with Cd2+

M. D. Groppa; M. P. Ianuzzo; M. L. Tomaro; M. P. Benavides

2007-01-01

40

Iron monosulfide as a scavenger for dissolved hexavalent chromium and cadmium.  

PubMed

Iron sulfide minerals are common components of soil/sedimentary environments. Reactions near the surfaces of iron sulfides play important roles in metal retention, mobility, and bioavailability. A series of batch experiments was conducted to study the removal of aqueous chromium and cadmium by iron monosulfide. Hexavalent chromium was reduced to Cr(III) by iron monosulfide with simultaneous precipitation of chromium and iron oxyhydroxide. In contrast to chromium, the primary retention mechanism of cadmium by iron monosulfide was lattice exchange. Surface adsorption to iron monosulfide and precipitation with sulfide on the iron monosulfide surface also contributed to the removal of aqueous cadmium. New phases of both chromium and cadmium were confirmed with transmission electron microscopy. The solution pH was an important factor in this research; it can change particle surface charge and metal species, hence affecting the removal of chromium, but not cadmium. Ferrous ions without FeS exhibited less Cr(VI) removal than with FeS, which might be owing to sulfides from FeS and the existence of the solid phase. Iron monosulfide exhibited higher removal efficiency for chromium and cadmium than zero valent iron and other iron oxide minerals, and the synergistic effect of ferrous iron and sulfide appeared to cause this result. PMID:18844124

Jo, S; Lee, J Y; Kong, S H; Choi, J; Park, J W

2008-09-01

41

High affinity of cadmium and copper to head kidney of common carp (Cyprinus carpio L.).  

PubMed

The aim of the present study was to evaluate bioaccumulation of metals in various tissues of the freshwater fish Cyprinus carpio L. exposed to cadmium and copper (a xenobiotic and a microelement). The fish were subjected to short-term (3 h, Cd-S and Cu-S) or long-term (4 weeks, Cd-L and Cu-L) exposures to 100 % 96hLC?? or 10 % 96hLC??, respectively. Blood, gill, liver, head and trunk kidney were isolated weekly from 5 fish of each group for 4 weeks (post-short-term exposure and during long-term exposure). Atomic absorption spectrophotometry technique was applied to measure concentrations of metals (Cd and Cu) in fish tissues. Initial concentrations of copper in fish tissues were higher than levels of cadmium. Cadmium and copper levels increased in all tissues of metal-exposed fish. After short-term exposures (at higher concentration) and during long-term exposures (at lower concentration), similar changes in metal concentrations were observed. The values of accumulation factor (ratio of final to initial metal concentration) were higher for cadmium as compared to copper. Comparison of metal levels and accumulation factors in various tissues revealed that cadmium and copper showed very high affinity to head kidney of common carp (higher than to other tissues), but accumulation factors for cadmium in trunk, head kidney and liver were much higher than for copper. The concentrations of copper in organs of Cu-exposed fish increased only slightly and quickly returned to the control level, which shows that fish organism easily buffered metal level. On the other hand, concentrations of cadmium considerably increased and remained elevated for a long time which suggests that activation of mechanisms of sequestration and elimination of cadmium required more time. PMID:23756826

Kondera, El?bieta; ?ugowska, Katarzyna; Sarnowski, Piotr

2014-02-01

42

Acute and chronic exposure of Dunaliella salina and Chlamydomonas bullosa to copper and cadmium: Effects on growth  

Microsoft Academic Search

Effective copper and cadmium concentrations which limited the growth of two chlorophytes by 50%, EC(50)s, after 96 h of static exposure were determined. EC(50)s were 5.94 µgM copper and 4.55 µM cadmium for Dunaliella salina, and 0.78 µM copper and 0.025 µM cadmium for Chlamydomonas bullosa. The relationship of the two cations was synergistic towards the growth of both species.

I. Visviki; J. W. Rachlin

1994-01-01

43

Copper Stress Affects Iron Homeostasis by Destabilizing Iron-Sulfur Cluster Formation in Bacillus subtilis?  

PubMed Central

Copper and iron are essential elements for cellular growth. Although bacteria have to overcome limitations of these metals by affine and selective uptake, excessive amounts of both metals are toxic for the cells. Here we investigated the influences of copper stress on iron homeostasis in Bacillus subtilis, and we present evidence that copper excess leads to imbalances of intracellular iron metabolism by disturbing assembly of iron-sulfur cofactors. Connections between copper and iron homeostasis were initially observed in microarray studies showing upregulation of Fur-dependent genes under conditions of copper excess. This effect was found to be relieved in a csoR mutant showing constitutive copper efflux. In contrast, stronger Fur-dependent gene induction was found in a copper efflux-deficient copA mutant. A significant induction of the PerR regulon was not observed under copper stress, indicating that oxidative stress did not play a major role under these conditions. Intracellular iron and copper quantification revealed that the total iron content was stable during different states of copper excess or efflux and hence that global iron limitation did not account for copper-dependent Fur derepression. Strikingly, the microarray data for copper stress revealed a broad effect on the expression of genes coding for iron-sulfur cluster biogenesis (suf genes) and associated pathways such as cysteine biosynthesis and genes coding for iron-sulfur cluster proteins. Since these effects suggested an interaction of copper and iron-sulfur cluster maturation, a mutant with a conditional mutation of sufU, encoding the essential iron-sulfur scaffold protein in B. subtilis, was assayed for copper sensitivity, and its growth was found to be highly susceptible to copper stress. Further, different intracellular levels of SufU were found to influence the strength of Fur-dependent gene expression. By investigating the influence of copper on cluster-loaded SufU in vitro, Cu(I) was found to destabilize the scaffolded cluster at submicromolar concentrations. Thus, by interfering with iron-sulfur cluster formation, copper stress leads to enhanced expression of cluster scaffold and target proteins as well as iron and sulfur acquisition pathways, suggesting a possible feedback strategy to reestablish cluster biogenesis.

Chillappagari, Shashi; Seubert, Andreas; Trip, Hein; Kuipers, Oscar P.; Marahiel, Mohamed A.; Miethke, Marcus

2010-01-01

44

Zinc-, copper- and cadmium-binding protein in Ehrlich ascites tumour cells.  

PubMed Central

The properties of Ehrlich ascites tumour cells exposed in vivo to cadmium were investigated as a function of the zinc status of the host animals. Tumour-cell growth was inhibited by cadmium in both zinc-sufficient and zinc-deficient animals. However, cells in zinc-sufficient tumours accumulate much less cadmium than those in deficient tumours. The subcellular distributions of cadmium and zinc do not depend on zinc status. Cadmium and zinc are bound to a low-molecular-weight protein with properties similar to metallothionein. Without exposure to cadmium, a zinc- and copper-binding protein is still present that behaves like a metallothionein. This protein can rapidly bind cadmium added to Ehrlich cells in vitro. It is shown that the zinc- and copper-binding protein contains free thiol groups. Ehrlich cells isolated from cadmium-treated animals are viable and show normal incorporation of uridine into RNA, but the cellular uptake of thymidine and its incorporation into DNA are inhibited.

Koch, J; Wielgus, S; Shankara, B; Saryan, L A; Shaw, C F; Petering, D H

1980-01-01

45

Tissue iron, copper and zinc levels in offspring of iron-sufficient and iron-deficient rats.  

PubMed

To study the effects of iron nutriture on tissue iron, copper and zinc contents, we fed iron-deficient or control diets to pregnant rats and their offspring. Pups were weaned to the same or opposite diet as that fed to their dams, yielding four groups: control-control (CC), control-deficient (CD), deficient-control (DC) and deficient-deficient (DD). Offspring were killed at 2, 21, 30, 60 and 90 days of age. Iron deficiency, induced by feeding a 5 ppm iron diet to the dam and/or to the weanlings, resulted in impaired body growth, lower hemoglobin and hematocrit levels and reduced iron levels in liver, spleen and kidney of the offspring. Two-day-old iron-deficient pups had hepatic copper levels 1.5- fold higher than control pups. By the end of the suckling period, hepatic copper levels in iron-deficient pups were 3-fold greater than those of control pups. Hepatic copper concentration in control-fed rats (CC and DC) declined with maturation. In deficient rats (CD and DD), this normal decrease in hepatic copper did not occur and in CD rats, there was a progressive accumulation of copper in the liver. Renal zinc concentrations were lower in CD and DD than in control-fed animals at 60 and 90 days of age. These interactions among iron, copper and zinc may assume clinical importance since iron deficiency is a common nutritional problem. PMID:7463170

Sherman, A R; Tissue, N T

1981-02-01

46

Role of iron in jejunal uptake of cadmium in the newborn rat  

SciTech Connect

There is evidence that suckling animals and children have a greater capacity for intestinal transport of both essential and nonessential metals than do adults of the species. It has also been observed in experiments using adult animals that the intestinal transport of iron and the nonessential metal cadmium interact with one another. In the study reported here, the influence of tissue iron status on jejunal uptake of cadmium was investigated in suckling, adolescent, and young adult rats using an in situ incubation technique. In the presence of 0.4 mM FeSO/sub 4/, intestinal uptake of cadmium was significantly decreased in 14-d-old pups. Access to an iron-deficient diet reduced tissue iron levels in 28- and 42-d-old but not in 14-d-old rats. Intestinal uptake of cadmium was significantly greater in 28- and 42-d-old rats placed on the iron-deficient diet but did not change in 14-d-old rats compared to controls. In suckling rats injected with iron dextran over a six-d period, a significant decrease in intestinal uptake of both cadmium and iron was observed compared to controls. The results of the present study suggest that intestinal cadmium transport in the suckling, as well as the adolescent and young adult rat, interacts with, at least in part, the pathway responsible for iron transport.

Leon, L.; Johnson, D.R.

1985-01-01

47

Spatial Distribution of Total Cadmium, Copper, and Zinc in the Zebra Mussel ( Dreissena polymorpha) Along the Upper St. Lawrence River  

Microsoft Academic Search

The zebra mussel (Dreissena polymorpha) was utilized to assess the spatial distribution of three trace metals, cadmium, copper, and zinc, in the upper St. Lawrence River and to test the hypothesis that outflow from Lake Ontario influenced levels of these metals in near-shore biota. Zebra mussels, collected from twelve sites along the southern shore, were analyzed for total cadmium, copper,

Carolyn Johns

2001-01-01

48

Acute and chronic exposure of Dunaliella salina and Chlamydomonas bullosa to copper and cadmium: Effects on ultrastructure  

Microsoft Academic Search

The ultrastructural changes of Dunaliella salina and Chlamydomonas bullosa taking place after short term exposure to established copper and\\/or cadmium EC(50) or exposure to low levels of these cations for 8 months were examined. Cadmium had a greater impact on the ultrastructure of these species than copper. Metal stress affected a variety of cellular parameters including total cell volume, pyrenoid,

I. Visviki; J. W. Rachlin

1994-01-01

49

Effects of copper and cadmium on osmoregulation and oxygen consumption in two species of estuarine crabs  

Microsoft Academic Search

Green crabs (Carcinus maenas) and rock crabs (Cancer irroratus) were exposed to various concentrations of copper as cupric chloride (CuCl2 · 2 H2O), and cadmium as cadmium chloride (CdCl2 · 21\\/2 H2O) for 48 h. The exposures were conducted at 5 different salinities. At the end of each exposure period, tests of blood-serum osmolality and gill-tissue oxygen consumption were performed.

F. P. Thurberg; M. A. Dawson; R. S. Collier

1973-01-01

50

The role of microRNAs in copper and cadmium homeostasis  

SciTech Connect

Essential heavy metals (e.g., copper) and non-essential metals (e.g., cadmium) are both toxic to plants at high concentrations. Recently, microRNAs (miRNAs) have emerged as important modulators of plants adaptive response to heavy metal stress. Plant miRNAs negatively regulate target mRNAs by post-transcriptional cleavage. miR398 regulates copper homeostasis via down-regulating the expression of Cu,Zn-superoxide dismutase (CSD), a scavenger of superoxide radicals. miR393 and miR171 play an important role in cadmium stress mediation. This review focuses on the recent advance in the involvement of miRNAs in copper and cadmium stress regulatory networks in plants.

Ding, Yan-Fei [State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310029 (China)] [State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310029 (China); Zhu, Cheng, E-mail: pzhch@zju.edu.cn [State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310029 (China)] [State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310029 (China)

2009-08-14

51

Response to copper and cadmium stress in wild-type and copper tolerant strains of the lichen alga Trebouxia erici : metal accumulation, toxicity and non-protein thiols  

Microsoft Academic Search

Cysteine, glutathione (GSH) and phytochelatins were determined in the cells of both wild and copper tolerant strains of the\\u000a lichen alga Trebouxia erici following short-term (24 h) exposure to copper and cadmium and long-term (4 weeks) exposure to copper. Both metals caused\\u000a concentration dependent synthesis of phytochelatins (PC2–PC5), but cadmium was a more potent activator of phytochelatin synthesis, even inducing synthesis of

Martin Ba?kor; Barbara Pawlik-Skowro?ska; Jana Bud’ová; Tadeusz Skowro?ski

2007-01-01

52

Physiological responses of Matricaria chamomilla to cadmium and copper excess.  

PubMed

Physiological responses of Matricaria chamomilla plants exposed to cadmium (Cd) and copper (Cu) excess (3, 60, and 120 microM for 7 days) with special emphasis on phenolic metabolism were studied. Cu at 120 microM reduced chamomile growth, especially in the roots where it was more abundant than Cd. Notwithstanding the low leaf Cu amount (37.5 microg g(-1) DW) in comparison with Cd (237.8 microg g(-1) DW) at 120 microM, it caused reduction of biomass accumulation, F(v)/F(m) ratio and soluble proteins. In combination with high accumulation of phenolics, strong reduction of proteins and high GPX activity in the roots, this supports severe redox Cu properties. In terms of leaf phenylalanine ammonia-lyase (PAL) activity, it seems that Cd had a stimulatory effect during the course of the experiment, whereas Cu was found to stimulate it after 7-day exposure. The opposite trend was visible in the roots, where Cd had a stimulatory effect at high doses but Cu mainly at the highest dose. This supports the assumption of different PAL time dynamics under Cd and Cu excess. A dose of 60 and 120 microM Cu led to 2- and 3-times higher root lignin accumulation while the same Cd doses increased it by 33 and 68%, respectively. A Cu dose of 120 microM can be considered as limiting for chamomile growth under conditions of present research, while resistance to high Cd doses was confirmed. However, PAL and phenolics seemed to play an important role in detoxification of Cd- and Cu-induced oxidative stress. PMID:18214924

Kovácik, Jozef; Backor, Martin; Kaduková, Jana

2008-02-01

53

Effect of copper additions on the mechanical properties of iron  

NASA Astrophysics Data System (ADS)

The effect of copper alloying on the mechanical properties of iron is studied. Alloying of a model material (armco-iron) with 0.2-2.0% Cu is shown to increase the strength characteristics by a factor of 1.5-2.5 and to decrease the ductility by 8-60%.

Kostina, M. V.; Perkas, M. M.; Shelest, A. E.; Yusupov, V. S.

2011-05-01

54

Reduction of copper sulphate with elemental iron for preparation of copper nanoparticles  

NASA Astrophysics Data System (ADS)

Reduction of copper sulphate with elemental iron also known as cementation is a well known process used for the recovery of copper for a long time. In this study, the kinetics of the reaction of copper sulphate with iron wire and iron powder has been investigated. The reaction kinetics was studied as a function of different process parameters such as initial concentration, temperature and pH. In this research work, the effects of the above three parameters were studied for both types of iron substrates. It was found that with the iron wire the reaction obeys first order kinetics with respect to copper concentration whereas with the iron powder the order was found to be 1.5. The initial concentration was found to have considerable effect on the reaction kinetics of copper sulphate with elemental iron. The rate of reaction increases with an increase in the initial copper concentration up to a certain level and then decreases for the case of iron wire. However, for the reaction of copper sulphate with iron powder, the reaction rate decreases with an increase in the initial copper concentration. The effect of temperature on the reaction rate of copper sulphate for both types iron substrates (iron wire and iron powder) has also been studied in the temperature range of 23-54ºC. In both the cases, the reaction rate increases with an increase in temperature according to Arrhenius law. The activation energy for the reactions of copper sulphate with iron wire and iron powder was found to be 25.36 kJ/mol and 26.32 kJ/mol, respectively. The copper cementation reaction was found to be suitable to operate at a pH of 2.5-3 for iron wire and a pH of 3-4 for iron powder considering possible inhibition by copper hydroxyl complex formation at higher pH and the possible excess iron consumption by hydrogen reduction at lower pH. The copper particles were produced by the reduction of copper sulphate with elemental iron. The produced copper particles were obtained in the micro to nano range. Nowadays, nano sized particles has potential applications in different engineering and industrial fields. In this research work, emphasis was given to produce copper nano-particles. The reaction of copper sulphate solution with iron wire was studied in the presence of different organic solvents to verify the size and purity of the produced copper particles. 1-butanol proved to be a competent solvent in producing nearly nano sized copper particles with particles size as small as 165 nanometers in the form of clusters and purity as high as 93.67 weight% of copper. In order to determine the copper particles with the smallest size (nano range) and copper purity to a considerable level, characterization was done with the produced copper particles. For this purpose, the effect of sonication, addition of surfactant and chelation by adding EDTA were studied. It can be concluded that nano size copper particles with size less than 100 nm with copper purity of 100% were produced by reaction of 5% copper sulphate solution in the presence of 2 ml surfactant with iron wire and sonication. These copper nano particles have potential applications as catalysts for different industrial organic reactions. Finally, optimization studies of the process parameters effect on the reaction yield of copper sulphate with both types of iron substrates (wire and powder) were carried out using MATLAB 7.0 software. In this study, the relationship between three process variables namely the initial concentration of copper, temperature and pH of solution with reaction yield of copper cementation reaction was investigated for both the cases. Cubic mixture models were developed by using three levels full factorial design to find out the main effects and interactions of these process variables on the reaction yields of copper. The validity of the cubic mixture regressed models have been verified with high regression coefficients and through normal probability curves for residuals. Finally, response surface methodology was used to determine the optimum operating conditions of the cementation re

Nazim, Muhammad

55

Role of trace elements in cadmium chloride uptake in hepatoma cell lines  

Microsoft Academic Search

Cadmium coexists with other metals in various products. Releases of cadmium in the environment occur in parallel to the release of other metals including copper, iron and zinc which also have an essential role in human homeostasis as they participate in various biochemical pathways. We studied the interaction of iron, copper, zinc and calcium channel blockers (nifedipine and verapamil) with

George Fotakis; John A. Timbrell

2006-01-01

56

Mortality of copper cadmium alloy workers with special reference to lung cancer and non-malignant diseases of the respiratory system, 1946-92.  

PubMed Central

OBJECTIVES--To identify and quantify any relations between occupational exposure to cadmium oxide fume and mortalities from lung cancer and from chronic non-malignant diseases of the respiratory system. METHODS--The mortality experience of 347 copper cadmium alloy workers, 624 workers employed in the vicinity of copper cadmium alloy work (vicinity workers), and 521 iron and brass foundry workers (all men) was investigated for the period 1946-92. All subjects were first employed in these types of work in the period 1922-78 and for a minimum period of one year at one of two participating factories. Two analytical approaches were used, indirect standardisation and Poisson regression. RESULTS--Compared with the general population of England and Wales, mortality from lung cancer among copper cadmium alloy workers was close to expectation (observed deaths 18, expected deaths 17.8, standardised mortality ratio (SMR) 101, 95% confidence interval (95% CI) 60 to 159). A significant excess was shown for lung cancer among vicinity workers but not among iron and brass foundry workers (vicinity workers: observed 55, expected 34.3, SMR 160, 95% CI 121 to 209, P < 0.01; iron and brass foundry workers: observed 19, expected 17.8, SMR 107, 95% CI 64 to 167). Increased SMRs for non-malignant diseases of the respiratory system were shown for each of the three groups (alloy workers: observed 54, expected 23.5, SMR 230, 95% CI 172 to 300, P < 0.001; vicinity workers: observed 71, expected 43.0, SMR 165, 95% CI 129 to 208, P < 0.001; iron and brass foundry workers: observed 34, expected 17.1, SMR 199, 95% CI 137 to 278, P < 0.01). Work histories of the copper cadmium alloy workers were combined with independent assessments of cadmium exposures over time to develop individual estimates of cumulative exposure to cadmium; this being a time dependent variable. Poisson regression was used to investigate risks of lung cancer and risks of chronic non-malignant diseases of the respiratory system in relation to three levels of cumulative cadmium exposure (< 1600, 1600-4799, > or = 4800 micrograms.m-3.y). After adjustment for age, year of starting alloy work, factory, and time from starting alloy work, there was a significant positive trend (P < 0.01) between cumulative exposure to cadmium and risks of mortality from chronic non-malignant diseases of the respiratory system. Relative to a risk of unity for the lowest exposure category, risks were 4.54 (95% CI 1.96 to 10.51) for the middle exposure category and 4.74 (95% CI 1.81 to 12.43) for the highest exposure category. There was a non-significant negative trend between cumulative cadmium exposure and risks of mortality from lung cancer. Relative to a risk of unity for the lowest exposure category, risks were 0.85 (95% CI 0.27 to 2.68) for the middle exposure category and 0.81 (95% CI 0.18 to 3.73) for the highest exposure category. Similar findings were obtained when adjustment was made for age only. CONCLUSIONS--The findings are consistent with the hypothesis that exposure to cadmium oxide fume increases risks of mortality from chronic non-malignant diseases of the respiratory system. The findings do not support the hypothesis that exposure to cadmium oxide fume increases risks of mortality for lung cancer.

Sorahan, T; Lister, A; Gilthorpe, M S; Harrington, J M

1995-01-01

57

Kinetics of iron–copper sulphides oxidation in relation to protohistoric copper smelting  

Microsoft Academic Search

This article deals with one specific step of the copper extractive metallurgy process: the roasting of iron–copper sulphides.\\u000a It aims at shedding light on an archaeological issue: the reconstruction of the copper extractive metallurgy processes during\\u000a protohistory (IVe–IIe millennium BC). Experimental simulations are performed at laboratory scale by modelizing the conditions of protohistoric\\u000a furnaces. Kinetic of roasting is studied by

Emilien BurgerDavid Bourgarit; David Bourgarit; Vincent Frotté; Fabien Pilon

2011-01-01

58

The effect of copper on iron reduction and its application to the determination of total iron content in iron and copper ores by potassium dichromate titration.  

PubMed

The International Standard Organization (ISO) specifies two titrimetric methods for the determination of total iron content in iron ores using potassium dichromate as titrant after reduction of the iron(III) by tin(II) chloride and/or titanium(III) chloride. These two ISO methods (ISO2597-1 and ISO2597-2) require nearly boiling-point temperature for iron(III) reduction and suffer from copper interference and/or mercury pollution. In this study, potassium borohydride was used for reduction of iron(III) catalyzed by copper ions at ambient temperatures. In the absence of copper, iron(III) reduction by potassium borohydride was sluggish while a trace amount of copper significantly accelerated the reduction and reduced potassium borohydride consumption. The catalytic mechanism of iron(III) reduction in sulfuric acid and hydrochloric acid was investigated. Potassium borohydride in sodium hydroxide solution was stable without a significant degradation within 24h at ambient conditions and the use of potassium borohydride prepared in sodium hydroxide solution was safe and convenient in routine applications. The applicability of potassium borohydride reduction for the determination of total iron content by potassium dichromate titration was demonstrated by comparing with the ISO standard method using iron and copper ore reference materials and iron ore samples. PMID:24840467

Hu, Hanjun; Tang, Yang; Ying, Haisong; Wang, Minghai; Wan, Pingyu; Jin Yang, X

2014-07-01

59

Loading estimates of lead, copper, cadmium, and zinc in urban runoff from specific sources  

Microsoft Academic Search

Urban stormwater runoff is being recognized as a substantial source of pollutants to receiving waters. A number of investigators have found significant levels of metals in runoff from urban areas, especially in highway runoff. As an initiatory study, this work estimates lead, copper, cadmium, and zinc loadings from various sources in a developed area utilizing information available in the literature,

Allen P Davis; Mohammad Shokouhian; Shubei Ni

2001-01-01

60

Distribution of the Metals Lead, Cadmium, Copper, and Zinc in the Top Soil of Cartagena, Spain  

Microsoft Academic Search

This article presents the results of the analysis of the metals lead, cadmium, copper, zinc and aluminum, conducted on a total of 112 soil samples arising from 57 sampling points, distributedthroughout the Cartagena area in southeastern Spain. Both, totalmetal content and soluble fraction (1 M nitric acid medium, exchangeable fraction) were analyzed. Soil samples were taken on the surface of

M. J. Martínez García; S. Moreno-Grau; J. J. Martínez García; J. Moreno; J. Bayo; J. J. Guillén Pérez; J. Moreno-Clavel

2001-01-01

61

Distribution of copper, lead, cadmium and zinc concentrations in soils around Kabwe town in Zambia  

Microsoft Academic Search

The extent of pollution of the environment as a result of mining activities in Kabwe, the provincial capital of Central province in Zambia has not yet been evaluated. Mining of lead and zinc were the core activities of Kabwe mine while cadmium and silver were produced as by-products. The smelting processes produced a significant amount of copper. The spatial distribution

Backsion D. Tembo; Kwenga Sichilongo; Joseph Cernak

2006-01-01

62

Effect of Organic Matter on the Release Behavior and Extractability of Copper and Cadmium in Soil  

Microsoft Academic Search

Land disposal of organic waste materials may alter the heavy metal status of the soil by affecting metal solubility or dissociation kinetics. The aim of this investigation was to study the influences poultry manure and pistachio compost (at the rate of 300 g kg) on release behavior and extractability of copper (Cu) and cadmium (Cd) in two soils of Iran.

Leila Sadegh Kasmaei; Majid Fekri

2012-01-01

63

Polyamine metabolism in sunflower and wheat leaf discs under cadmium or copper stress  

Microsoft Academic Search

The influence of Cd2+ or Cu2+ on polyamine (Pa) metabolism and ethylene evolution was studied in sunflower and wheat leaf-discs. Both metals increased putrescine (Put) content in wheat leaves 280 and 90%, respectively, but reduced this Pa in sunflower leaves by about 50% of the control values. Spermidine content was diminished in cadmium and copper sunflower treated leaves (41 and

Mar??a D Groppa; Mar??a P Benavides; Mar??a L Tomaro

2003-01-01

64

Calibration Equations for Energy-Dispersive XRF Determination of Copper, Iron and Lead in Copper Ore Slurries.  

National Technical Information Service (NTIS)

Calibration equations for the X-ray fluorescence analysis determination of copper, iron and lead in copper ore slurries have been derived and tested. The measurement of Ksub( alpha ) lines of copper and iron and Lsub( alpha ) line of lead excited by rays ...

M. Lakosz

1976-01-01

65

Copper and cadmium adsorption on pellets made from fired coal fly ash.  

PubMed

Studies on the utilization of low cost adsorbents for removal of heavy metals from wastewaters are gaining attention. Fired coal fly ash, a solid by-product that is produced in power plants worldwide in million of tonnes, has attracted researchers' interest. In this work, fly ash was shaped into pellets that have diameter in-between 3-8mm, high relative porosity and very good mechanical strength. The pellets were used in adsorption experiments for the removal of copper and cadmium ions from aqueous solutions. The effect of agitation rate, equilibration time, pH of solution and initial metal concentration were studied. The adsorption of both cations follows pseudo-second order kinetics reaching equilibrium after an equilibration time of 72 h. The experimental results for copper and cadmium adsorption fit well to a Langmuirian type isotherm. The calculated adsorption capacities of pellets for copper and cadmium were 20.92 and 18.98 mg/g, respectively. Desorption experiments were performed in several extraction media. The results showed that both metals were desorbed substantially from pellets under acidic solutions. For this reason, metal saturated pellets were encapsulated in concrete blocks synthesized from cement and raw pulverized fly ash in order to avoid metal desorption. The heavy metals immobilization after encapsulation in concrete blocks was tested through desorption tests in several aqueous media. The results showed that after 2 months in acidic media with pH 2.88 and 4.98 neither copper nor cadmium were desorbed thus indicating excellent stabilization of heavy metals in the concrete matrix. As a conclusion, the results showed that fly ash shaped into pellets could be considered as a potential adsorbent for the removal of copper and cadmium from wastewaters. Moreover, the paper proposes an efficient and simple stabilization process of the utilized adsorbents thus guarantying their safe disposal in industrial landfills and eliminating the risk of pollution for groundwater and other natural water receivers. PMID:17416461

Papandreou, A; Stournaras, C J; Panias, D

2007-09-30

66

Iron Deficiency Increases Blood Cadmium Levels in Adolescents Surveyed in KNHANES 2010-2011.  

PubMed

Discrepancies have been reported in the relationships between iron and cadmium concentrations. The distribution of blood cadmium concentrations was assessed in a representative sample of Korean adolescents participating in the Korean National Health and Nutritional Examination Survey (KNHANES) 2010-2011, and the association between blood cadmium and iron concentrations was determined. This study was based on data from KNHANES, in which a rolling sampling design was used to perform a complex, stratified, multistage probability cluster survey of a representative sample of the noninstitutionalized civilian population in South Korea. Serum ferritin was categorized as low (<15.0 ?g/L), low normal (15.0-<30.0 ?g/L for girls, 15.0-<50.0 ?g/L for boys), or normal (?30.0 ?g/L for girls, ?50.0 ?g/L for boys), and the association between serum ferritin and blood cadmium concentrations was assessed after adjustment for various demographic and lifestyle factors. The geometric mean (GM) of blood cadmium was significantly higher among both boys and girls in the low than in the normal ferritin group. After controlling for covariates, multiple regression analysis showed that blood cadmium concentration was inversely correlated with serum ferritin concentration in both boys and girls. In conclusion, iron deficiency is associated with increased blood cadmium concentrations in a representative sample of Korean adolescents, as evaluated in KNHANES. PMID:24797808

Lee, Byung-Kook; Kim, Suk Hwan; Kim, Nam-Soo; Ham, Jung-O; Kim, Yangho

2014-06-01

67

Genotoxicity and mutagenicity of iron and copper in mice  

Microsoft Academic Search

The toxicity of trace metals is still incompletely understood. We have previously shown that a single oral dose of iron or\\u000a copper induces genotoxic effects in mice in vivo, as detected by single cell gel electrophoresis (comet assay). Here, we report\\u000a the effect of these metals on subchronic exposure. Mice were gavaged for six consecutive days with either water, 33.2 mg\\/kg\\u000a iron,

Daniel Prá; Silvia Isabel Rech Franke; Raquel Giulian; Maria Lúcia Yoneama; Johnny Ferraz Dias; Bernardo Erdtmann; João Antonio Pêgas Henriques

2008-01-01

68

Iron may play a role in pancreatic atrophy in copper deficiency  

SciTech Connect

The present study was undertaken to determine if pancreatic atrophy in copper deficient rats fed fructose is associated with excessive iron deposition. Weanling male and female rats were fed a copper deficient or copper adequate diet containing 62% carbohydrate as either fructose or starch. Another group of weanling rats consumed a copper deficient diet containing fructose that was low in iron. After consuming their respective diets for five weeks, the highest pancreatic iron concentration was seen in male rats consuming the copper deficient diet containing fructose. These animals also exhibited pancreatic atrophy. In contrast, neither copper deficient female rats fed fructose nor males fed starch exhibited pancreatic atrophy and their pancreata did not contain high levels of iron. In addition, reducing the availability of dietary iron in copper deficient rats fed fructose decreased pancreatic iron concentration and ameliorated the pathology. The data suggest that pancreatic atrophy in copper deficiency may be related to iron deposition in that tissue.

Fields, M.; Lewis, C.G.; Lure, M.D. (Georgetown Univ. Medical Center, Washington, DC (United States) Dept. of Agriculture, Beltsville, MD (United States) Univ. of Maryland, College Park (United States))

1991-03-15

69

SEPARATION OF CADMIUM FROM URANIUM, COBALT, NICKEL, MANGANESE, ZINC, COPPER, TITANIUM, AND OTHER ELEMENTS BY CATION EXCHANGE CHROMATOGRAPHY  

Microsoft Academic Search

A study of the distribution curves of cations with AG 5OW-X8 resin in ; hydrochloric acid showed that most cations are adsorbed strongly from 0.5 N ; hydrochloric acid, while cadmium is not. This fact was used to develop a cation ; exchange chromatographic procedure to separate cadmium from uranium, cobalt, ; nickel, manganese, zinc, copper, and titanium. Other cations

F. W. E. Strelow; F. W. E

1960-01-01

70

Cadmium, zinc, lead, and copper in livers and kidneys of cattle in the neighbourhood of zinc refineries  

Microsoft Academic Search

Cattle in the Kempen area (in the province North-Brabant, the Netherlands) were investigated for cadmium, lead, zinc, and copper in livers and kidneys. The animals originated from farms located within a 20 km radius around several zinc refinery plants. The local soil is polluted with zinc and cadmium because of a thermal refining process used in the past.

Th. J. Spierenburg; G. J. Graaf; A. J. Baars; D. H. J. Brus; M. J. M. Tielen; B. J. Arts

1988-01-01

71

Optimization of the electrocoagulation process for the removal of copper, lead and cadmium in natural waters and simulated wastewater  

Microsoft Academic Search

Chemical, electrochemical and flow variables were optimized to examine the effectiveness of the electrocoagulation process for the removal of copper, lead and cadmium. The electrochemical process, which uses electrodes of commercial laminate steel, was applied to simulated wastewater containing 12mgdm?3 of copper, 4mgdm?3 of lead and 4mgdm?3 of cadmium. The optimum conditions for the process were identified as pH=7, flow

Claudio Escobar; César Soto-Salazar; M. Inés Toral

2006-01-01

72

Iron inhibits neurotoxicity induced by trace copper and biological reductants  

Microsoft Academic Search

The extracellular microenvironment of the brain contains numerous biological redox agents, including ascorbate, glutathione, cysteine and homocysteine. During ischemia\\/reperfusion, aging or neurological disease, extracellular levels of reductants can increase dramatically owing to dysregulated homeostasis. The extracellular concentrations of transition metals such as copper and iron are also substantially elevated during aging and in some neurodegenerative disorders. Increases in the extracellular

Anthony R. White; Kevin J. Barnham; Xudong Huang; Irene Voltakis; Konrad Beyreuther; Colin L. Masters; Robert A. Cherny; Ashley I. Bush; Roberto Cappai

2004-01-01

73

The transition metals copper and iron in neurodegenerative diseases  

Microsoft Academic Search

Neurodegenerative diseases constitute a worldwide health problem. Metals like iron and copper are essential for life, but they are also involved in several neurodegenerative mechanisms such as protein aggregation, free radical generation and oxidative stress. The role of Fe and Cu, their pathogenic mechanisms and possible therapeutic relevance are discussed regarding four of the most common neurodegenerative diseases, Alzheimer's, Parkinson's

Susana Rivera-Mancía; Iván Pérez-Neri; Camilo Ríos; Luis Tristán-López; Liliana Rivera-Espinosa; Sergio Montes

2010-01-01

74

Determination of silver, antimony, bismuth, copper, cadmium and indium in ores, concentrates and related materials by atomic-absorption spectrophotometry after methyl isobutyl ketone extraction as iodides.  

PubMed

Methods for determining ~ 0.2 mug g or more of silver and cadmium, ~ 0.5 mug g or more of copper and ~ 5 mug g or more of antimony, bismuth and indium in ores, concentrates and related materials are described. After sample decomposition and recovery of antimony and bismuth retained by lead and calcium sulphates, by co-precipitation with hydrous ferric oxide at pH 6.20 +/- 0.05, iron(III) is reduced to iron(II) with ascorbic acid, and antimony, bismuth, copper, cadmium and indium are separated from the remaining matrix elements by a single methyl isobutyl ketone extraction of their iodides from ~2M sulphuric acid-0.1M potassium iodide. The extract is washed with a sulphuric acid-potassium iodide solution of the same composition to remove residual iron and co-extracted zinc, and the extracted elements are stripped from the extract with 20% v v nitric acid-20% v v hydrogen peroxide. Alternatively, after the removal of lead sulphate by filtration, silver, copper, cadmium and indium can be extracted under the same conditions and stripped with 40% v v nitric acid-25% v v hydrochloric acid. The strip solutions are treated with sulphuric and perchloric acids and ultimately evaporated to dry ness. The individual elements are determined in a 24% v v hydrochloric acid medium containing 1000 mug of potassium per ml by atomic-absorption spectrophotometry with an air-acetylene flame. Tin, arsenic and molybdenum are not co-extracted under the conditions above. Results obtained for silver, antimony, bismuth and indium in some Canadian certified reference materials by these methods are compared with those obtained earlier by previously published methods. PMID:18964072

Donaldson, E M; Wang, M

1986-03-01

75

Lysozyme levels in rabbit lung after inhalation of nickel, cadmium, cobalt, and copper chlorides  

SciTech Connect

Groups of rabbits were exposed to chlorides of nickel, cadmium, copper, and cobalt at concentrations ranging from 0.2 to 0.6 mg/m/sup 3/ (as metal) for 4 to 6 weeks (5 days/weeks, 6 hr/day). Activity of lysozyme (muramidase) in lavage fluid, in alveolar macrophages, and in culture medium from macrophages incubated at 37/sup 0/C for 1 and 20 hr was estimated using the lyso-plate technique, agar plates with heat-killed Micrococcus lysodeikticus. In the nickel-exposed rabbits lysozyme activity in the mucous membrane from the left main bronchus was also estimated. Following nickel exposure the lysozyme level was significantly decreased in lavage fluid, macrophages, and in culture medium from incubated macrophages but remained unchanged in the mucous membrane. After exposure to cadmium, copper, and cobalt, lysozyme levels increased or were unchanged.

Lundborg, M.; Camner, P.

1984-08-01

76

A study of the stability of cadmium sulfide/copper sulfide solar cells  

NASA Astrophysics Data System (ADS)

The results of an experimental study of the intrinsic degradation mechanisms in cadmium sulfide/copper sulfide solar cells are reported. Behavior during degradation of both voltage and current is described. No major trend of fill factor degradation was observed for the primary cells used in this study, although significant degradation of this parameter has been observed in other cell types. The voltage degradation can be recovered by 'resting' or reverse biasing the cells, while recovery of the degradation of the light generated current requires refiring. Statistical summaries of degradation data, including degradation rates, for cell groups exposed to combinations of stresses (temperature, load, illumination, roof-top ambient) are presented. These indicate that open-circuit is the most stressful load condition. Possible mechanisms and causative factors for the observed degradation modes are discussed. Preliminary results of a study of the stability of cadmium sulfide/copper-indium selenide photovoltaic devices are also presented.

Noel, G. T.; Gaines, G. B.; Richard, N. A.

77

Lipid peroxidation in the gill and hepatopancreas of Oziotelphusa senex senex fabricius during cadmium and copper exposure  

SciTech Connect

Environmental contamination by metals has increased in recent years due to the excessive use of metals in agriculture and industry. Due to their bioconcentration, immutable and non-degradable properties, these metals constitute a major source of pollutants. Among these metals cadmium, lead and mercury are non-essential, where as copper, iron, manganese, and zinc are essential elements. They are required in trace amounts by all forms of life but are toxic when present in excess. Considerable information is available on the toxic effects of cadmium on biological mechanisms at all integration levels, such as molecular, biochemical, physiological and behavioural, in animals. It is also well known that heavy metal contamination alters cellular physiology, particularly by affecting aspects such as transport across plasma membranes, mitochondrial functions, lysosomal stability etc. Even though it has been demonstrated that the in vitro addition of heavy metals stimulates membrane lipid peroxidation, the in vivo effects exerted by different cations on this process are still not clear. The present work reports the effect of exposure to sublethal concentrations of heavy metals such as Cu and Cd on lipid peroxidation in the tissues of the edible freshwater crab, Oziotelphusa senex senex. 16 refs., 3 tabs.

Reddy, P.S. (Pondicherry Univ. (India)); Bhagyalakshmi, A. (Sri Padmavathi Women's Polytechnic, Tirupati (India))

1994-11-01

78

Lead, chromium, tin, iron and cadmium in foods in welded cans.  

PubMed

The levels of lead, chromium, tin, iron and cadmium in fruit and vegetables in welded tinplate cans were determined by atomic absorption spectrophotometry. The levels found were compared with those in foods in soldered tinplate cans and fresh foods. The results show that the lead levels in foods in welded cans were much lower than those in similar foods in soldered cans. Foods in unlacquered welded cans contain much more lead, chromium and tin than foods in lacquered welded cans. The cadmium and iron levels in canned fruit and vegetables in welded cans were similar to those found in the corresponding fresh foods. PMID:3653455

Jorhem, L; Slorach, S

1987-01-01

79

Multi?Walled Carbon Nanotubes as Sorbent for Flow Injection On?Line Microcolumn Preconcentration Coupled with Flame Atomic Absorption Spectrometry for Determination of Cadmium and Copper  

Microsoft Academic Search

Multi?walled carbon nanotubes (MWNTs) were used as sorbent for flow injection (FI) on?line microcolumn preconcentration coupled with flame atomic absorption spectrometry (FAAS) for determination of trace cadmium and copper in environmental and biological samples. Effective preconcentration of trace cadmium and copper was achieved in a pH range of 4.5–6.5 and 5.0–7.5, respectively. The retained cadmium and copper were efficiently eluted

2006-01-01

80

The role of microRNAs in copper and cadmium homeostasis  

Microsoft Academic Search

Essential heavy metals (e.g., copper) and non-essential metals (e.g., cadmium) are both toxic to plants at high concentrations. Recently, microRNAs (miRNAs) have emerged as important modulators of plants adaptive response to heavy metal stress. Plant miRNAs negatively regulate target mRNAs by post-transcriptional cleavage. miR398 regulates copper homeostasis via down-regulating the expression of Cu,Zn-superoxide dismutase (CSD), a scavenger of superoxide radicals.

Yan-Fei Ding; Cheng Zhu

2009-01-01

81

Cadmium toxicity induced alterations in the root proteome of green gram in contrasting response towards iron supplement.  

PubMed

Cadmium signifies a severe threat to crop productivity and green gram is a notably iron sensitive plant which shows considerable variation towards cadmium stress. A gel-based proteomics analysis was performed with the roots of green gram exposed to iron and cadmium combined treatments. The resulting data show that twenty three proteins were down-regulated in iron-deprived roots either in the absence (-Fe/-Cd) or presence (-Fe/+Cd) of cadmium. These down-regulated proteins were however well expressed in roots under iron sufficient conditions, even in the presence of cadmium (+Fe/+Cd). The functional classification of these proteins determined that 21% of the proteins are associated with nutrient metabolism. The other proteins in higher quantities are involved in either transcription or translation regulation, and the rest are involved in biosynthesis metabolism, antioxidant pathways, molecular chaperones and stress response. On the other hand, several protein spots were also absent in roots in response to iron deprivation either in absence (-Fe/-Cd) or presence (-Fe/+Cd) of cadmium but were well expressed in the presence of iron (+Fe/+Cd). Results suggest that green gram plants exposed to cadmium stress are able to change the nutrient metabolic balance in roots, but in the mean time regulate cadmium toxicity through iron supplements. PMID:24739807

Muneer, Sowbiya; Hakeem, Khalid Rehman; Mohamed, Rozi; Lee, Jeong Hyun

2014-01-01

82

Cadmium Toxicity Induced Alterations in the Root Proteome of Green Gram in Contrasting Response towards Iron Supplement  

PubMed Central

Cadmium signifies a severe threat to crop productivity and green gram is a notably iron sensitive plant which shows considerable variation towards cadmium stress. A gel-based proteomics analysis was performed with the roots of green gram exposed to iron and cadmium combined treatments. The resulting data show that twenty three proteins were down-regulated in iron-deprived roots either in the absence (?Fe/?Cd) or presence (?Fe/+Cd) of cadmium. These down-regulated proteins were however well expressed in roots under iron sufficient conditions, even in the presence of cadmium (+Fe/+Cd). The functional classification of these proteins determined that 21% of the proteins are associated with nutrient metabolism. The other proteins in higher quantities are involved in either transcription or translation regulation, and the rest are involved in biosynthesis metabolism, antioxidant pathways, molecular chaperones and stress response. On the other hand, several protein spots were also absent in roots in response to iron deprivation either in absence (?Fe/?Cd) or presence (?Fe/+Cd) of cadmium but were well expressed in the presence of iron (+Fe/+Cd). Results suggest that green gram plants exposed to cadmium stress are able to change the nutrient metabolic balance in roots, but in the mean time regulate cadmium toxicity through iron supplements.

Muneer, Sowbiya; Hakeem, Khalid Rehman; Mohamed, Rozi; Lee, Jeong Hyun

2014-01-01

83

Localization and Toxic Effects of Cadmium, Copper, and Uranium in Azolla1  

PubMed Central

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis. The relative content of copper was eightfold higher in the root than in the shoot, suggesting low mobility of this metal in Azolla plant. Cadmium relative content in the shoot was similar to its content in the root, hence its mobility was relatively high. The absence of significant uranium quantities in the shoot and its relative high content in the root suggest the immobility of this metal from Azolla root. Cadmium formed precipitates with phosphate and calcium in xylem cells of the shoot bundle and caused a two- to threefold increase in the content of phosphate in the root. Uranium in roots and cadmium in shoots were associated with calcium. All three treatments caused losses of potassium, chloride, and magnesium from Azolla roots. Accumulation of heavy metals in Azolla and their mobility from the root to the shoot can be correlated with damage caused by the loss of essential nutrients. Images Fig. 1 Fig. 2 Fig. 5 Fig. 7

Sela, Mordechai; Tel-Or, Elisha; Fritz, Eberhardt; Huttermann, Aloys

1988-01-01

84

Localization and toxic effects of cadmium, copper, and uranium in Azolla  

SciTech Connect

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis. The relative content of copper was eightfold higher in the root than in the shoot, suggesting low mobility of this metal in Azolla plant. Cadmium relative content in the shoot was similar to its content in the root, hence its mobility was relatively high. The absence of significant uranium quantities in the shoot and its relative high content in the root suggest the immobility of this metal from Azolla root. Cadmium formed precipitates with phosphate and calcium in xylem cells of the shoot bundle and caused a two- to threefold increase in the content of phosphate in the root. Uranium in roots and cadmium in shoots were associated with calcium. All three treatments caused losses of potassium, chloride, and magnesium from Azolla roots. Accumulation of heavy metals in Azolla and their mobility from the root to the shoot can be correlated with damage caused by the loss of essential nutrients.

Sela, M.; Tel-Or, E.; Fritz, E.; Huttermann, A.

1988-09-01

85

Localization and toxic effects of cadmium, copper, and uranium in azolla.  

PubMed

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis. The relative content of copper was eightfold higher in the root than in the shoot, suggesting low mobility of this metal in Azolla plant. Cadmium relative content in the shoot was similar to its content in the root, hence its mobility was relatively high. The absence of significant uranium quantities in the shoot and its relative high content in the root suggest the immobility of this metal from Azolla root. Cadmium formed precipitates with phosphate and calcium in xylem cells of the shoot bundle and caused a two- to threefold increase in the content of phosphate in the root. Uranium in roots and cadmium in shoots were associated with calcium. All three treatments caused losses of potassium, chloride, and magnesium from Azolla roots. Accumulation of heavy metals in Azolla and their mobility from the root to the shoot can be correlated with damage caused by the loss of essential nutrients. PMID:16666274

Sela, M; Tel-Or, E; Fritz, E; Huttermann, A

1988-09-01

86

Cadmium and copper induction of oxidative stress and antioxidative response in tomato ( Solanum lycopersicon ) leaves  

Microsoft Academic Search

We compare cadmium and copper induced oxidative stress in tomato leaves and the antioxidative enzyme response during a time\\u000a course of 96 h. Plants were subjected to 25 ?M of CdCl2 or CuSO4 and malondialdehyde (MDA) level and activity of guaiacol peroxidase, superoxide dismutase, catalase, ascorbate peroxidase\\u000a and glutathione reductase were determined. The results showed that there was an early increase in

Mediouni Chamseddine; Ben Ammar Wided; Houlné Guy; Chabouté Marie-Edith; Jemal Fatma

2009-01-01

87

Copper, zinc, cadmium and lead biosorption by Gymnogongrus torulosus. Thermodynamics and kinetics studies  

Microsoft Academic Search

Gymnogongrus torulosus adsorption efficiency for cadmium(II), copper(II), lead(II) and zinc(II) were studied in batch mode in different acidic conditions. The adsorbent removal efficiency was determined as a function of contact time, initial metal ions concentration, pH and temperature. G. torulosus was characterized by SEM, water adsorption surface area and EDS. The Langmuir, Freundlich, Dubinin–Radushkevich and Temkin models have been applied

María Mar Areco; María dos Santos Afonso

2010-01-01

88

Effect of adsorption on calibration graphs obtained for lead, cadmium and copper in natural water samples  

Microsoft Academic Search

Calibration graphs for lead, cadmium and copper have been obtained in natural water, in centrifuged natural water and. in distilled water. These calibration graphs were repeated in each medium one time when acidified to PH 2.2 and another time when buffered to pH 7.4. The shape of the calibration graphs obtained in the various types of media has been explained

Radi Salim

1987-01-01

89

Copper, Lead, Cadmium, and Zinc Sorption By Waterlogged and Air-Dry Soil  

Microsoft Academic Search

Competitive sorption of copper (Cu), lead (Pb), cadmium (Cd), and zinc (Zn) was studied in three soils of contrasting chemical and physical properties under air-dry and waterlogged conditions. Competitive sorption was determined using the standard batch technique using six solutions, each with Cu, Pb, Cd, and Zn concentrations of approximately 0, 2.5, 5, 10, 20, and 50?mg LWaterlogged soils tended

I. R. Phillips

1999-01-01

90

Adsorption of Copper, Nickel, and Cadmium on Goethite in the Presence of Organic Ligands  

Microsoft Academic Search

Adsorption of copper, cadmium and nickel at low concentrations on goethite was studied in the presence of the simple organic\\u000a ligands oxalate, salicylate, and pyromellitate. The experimental metal adsorption behavior was compared to calculations with\\u000a a surface complexation model to evaluate the most important interactions. Oxalate mostly decreased Cu and Ni adsorption at\\u000a high pH-values by competition between solution and

Diane Buerge-Weirich; Philippe Behra; Laura Sigg

2003-01-01

91

Effects of copper and cadmium on heavy metal polluted waterbody restoration by duckweed ( Lemna minor)  

Microsoft Academic Search

Aquatic plants have been identified as a potentially useful group for accumulating and bioconcentrating heavy metals. In the study, we investigated changes in the contents of soluble protein and photosynthetic pigments as well as the activity of antioxidant enzymes caused by copper sulfate and cadmium dichloride, respectively in duckweed (Lemna minor) during concentration-dependent exposure (0.05–20mgl?1) to metal salt. The results

Wenhua Hou; Xiao Chen; Guanling Song; Qunhui Wang; Chein Chi Chang

2007-01-01

92

Effect of Cadmium, Copper, and Lead on Different Enzyme Activities in a Native Forest Soil  

Microsoft Academic Search

Heavy metals contamination has been reported to affect enzymatic activities in soils. The objectives of this work were (i) to study the effect of cadmium [Cd(II)], copper [Cu(II)], and lead [Pb(II)] at different doses and different incubation times on arylsulphatase, ß-glucosidase, acid phosphatase, protease, and urease activities in a noncontaminated native forest soil and (ii) to analyze the potential use

D. Effron; A. M. de la Horra; R. L. Defrieri; V. Fontanive; R. M. Palma

2004-01-01

93

Cadmium, copper and zinc concentrations in hair of inhabitants of a cadmium polluted area  

Microsoft Academic Search

To investigate the present situation of inhabitants living in the cadmium polluted area of Toyama Prefecture of Japan, 95 hair samples were analyzed by neutron activation method. The median and the geometric standard deviation were determined from a cumulative frequency distribution curve of the elemental concentrations for each of 3 groups: male, female without perm and female with perm which

T. Takeuchi; Y. Nakano; S. Ohmori; A. Aoki; M. Kasuya

1990-01-01

94

Zinc, iron, manganese, and magnesium accumulation in crayfish populations near copper-nickel smelters at Sudbury, Ontario, Canada  

SciTech Connect

The Sudbury basin has been subjected to extreme ecological disturbances from logging, mining and smelting activities. Elevated concentrations of copper, cadmium, and nickel have been reported in crayfish populations close to the Sudbury smelting works. The present study compares concentrations of zinc (Zn), iron (Fe), manganese (Mn) and magnesium (Mg) in freshwater crayfish at selected distances of the habitat from the emission source. These metals were selected since they are known to be emitted in moderately high quantities into the Sudbury environment as byproduct of the smelting process. Various tissue concentrations in crayfish were also examined to determined specific tissue sites for these accumulations.

Bagatto, G.; Alikhan, M.A.

1987-06-01

95

Genes involved in cysteine metabolism of Chironomus tepperi are regulated differently by copper and by cadmium.  

PubMed

Freshwater invertebrates are often exposed to metal contamination, and changes in gene expression patterns can help understand mechanisms underlying toxicity and act as pollutant-specific biomarkers. In this study the expressions of genes involved in cysteine metabolism are characterized in the midge Chironomus tepperi during exposures to sublethal concentrations of cadmium and copper. These metals altered gene expression of the cysteine metabolism differently. Both metals decreased S-adenosylhomocysteine hydrolase expression and did not change the expression of S-adenosylmethionine synthetase. Cadmium exposure likely increased cystathionine production by up-regulating cystathionine-?-synthase (C?S) expression, while maintaining control level cysteine production via cystathionine-?-lyase (C?L) expression. Conversely, copper down-regulated C?S expression and up-regulated C?L expression, which in turn could diminish cystathionine to favor cysteine production. Both metals up-regulated glutathione related expression (?-glutamylcysteine synthase and glutathione synthetase). Only cadmium up-regulated metallothionein expression and glutathione S-transferase d1 expression was up-regulated only by copper exposure. These different transcription responses of genes involved in cysteine metabolism in C. tepperi point to metal-specific detoxification pathways and suggest that the transsulfuration pathway could provide biomarkers for identifying specific metals. PMID:24603357

Jeppe, Katherine J; Carew, Melissa E; Long, Sara M; Lee, Siu F; Pettigrove, Vincent; Hoffmann, Ary A

2014-05-01

96

Concentration and distribution of copper and cadmium in water, sediments, detritus, plants and animals in a hardwater lowland river  

Microsoft Academic Search

The concentration and distribution of copper (Cu) and cadmium (Cd) were examined in water, sediments, detritus, plants and animals in a small, lowland, hardwater river. Consistently higher concentrations of Cu and Cd were found in all types of samples from two sites. There were marked variations in metal concentrations between different types of samples, and between seasons. Copper and Cd

S. Smith; M.-H. Chen; R. G. Bailey; W. P. Williams

1996-01-01

97

OPT3 Is a Phloem-Specific Iron Transporter That Is Essential for Systemic Iron Signaling and Redistribution of Iron and Cadmium in Arabidopsis[W][OPEN  

PubMed Central

Iron is essential for both plant growth and human health and nutrition. Knowledge of the signaling mechanisms that communicate iron demand from shoots to roots to regulate iron uptake as well as the transport systems mediating iron partitioning into edible plant tissues is critical for the development of crop biofortification strategies. Here, we report that OPT3, previously classified as an oligopeptide transporter, is a plasma membrane transporter capable of transporting transition ions in vitro. Studies in Arabidopsis thaliana show that OPT3 loads iron into the phloem, facilitates iron recirculation from the xylem to the phloem, and regulates both shoot-to-root iron signaling and iron redistribution from mature to developing tissues. We also uncovered an aspect of crosstalk between iron homeostasis and cadmium partitioning that is mediated by OPT3. Together, these discoveries provide promising avenues for targeted strategies directed at increasing iron while decreasing cadmium density in the edible portions of crops and improving agricultural productivity in iron deficient soils.

Zhai, Zhiyang; Gayomba, Sheena R.; Jung, Ha-il; Vimalakumari, Nanditha K.; Pineros, Miguel; Craft, Eric; Rutzke, Michael A.; Danku, John; Lahner, Brett; Punshon, Tracy; Guerinot, Mary Lou; Salt, David E.; Kochian, Leon V.; Vatamaniuk, Olena K.

2014-01-01

98

EVALUATION OF IRON ON CADMIUM UPTAKE BY TOMATO, MOREL AND LEAF RED BEET IN HYDROPONIC CULTURE  

Microsoft Academic Search

The objective of this research was to determine the effect of iron (Fe) deficiency on the uptake of cadmium (Cd) by three plants: tomato (Lycopersicon esculentum Mill.), morel (Solanum nigrum L.), and leaf red beet (Beta vulgaris var.cicla L.) in hydroponic culture. We also investigated the influence of Fe deficiency on rhizosphere pH, bioconcentration factor (BCF), and translocation factor (TF)

T. Bao; L.-N. Sun; T.-H. Sun

2010-01-01

99

Significance of concentrations of lead, cadmium, and iron in the plumage of the feral pigeon  

Microsoft Academic Search

Lead, cadmium, and iron contamination was examined in the plumage of feral pigeons. Metal contamination in pigeons from different regions in Bratislava or in different seasons did not differ significantly; seasonal type of food did not significantly influence the concentrations. The blood of birds was examined for the presence of complement fixing antibodies toChlamydia psittaci. Birds with antibodies did not

Marifin Janiga; Blanka Mafikovskfi; Monika Bobal'ová; Gabriela ?ur?ová

1990-01-01

100

Copper, iron and zinc in Alzheimer's disease senile plaques  

Microsoft Academic Search

Concentrations of copper (Cu), iron (Fe) and zinc (Zn) were measured in the rims and cores of senile plaques (SP) and in the neuropil of the amygdala of nine Alzheimer's disease (AD) patients and in the neuropil of the amygdala of five neurologically normal control subjects using micro particle-induced X-ray emission (micro-PIXE). Comparison of SP rim and core values revealed

M. A Lovell; J. D Robertson; W. J Teesdale; J. L Campbell; W. R Markesbery

1998-01-01

101

Distribution of iron, copper and manganese in the Arabian Sea  

NASA Astrophysics Data System (ADS)

The distribution of iron, copper and manganese was studied on a zonal transect of the Arabian Sea during the SW monsoon in 2007. The distribution of metals in the eastern and western ends of the transect are completely different, with concentrations of Fe and Mn higher in the east, but copper much higher in the west. Redox cycling in the east, and enhanced ventilation in the west contributes to these processes. It seems likely that blooms of Phaeocystis sp. contribute to the pronounced surface depletion and oxicline regeneration we observe, particularly for copper. The results are very different than similar surveys in the Peru upwelling, indicating controls by very different processes. These results have important implications for carbon and nitrogen cycling, particularly for processes mediated by key Cu and Fe metalloenzymes.

Moffett, James

2014-05-01

102

Seminar on Role of Copper and Copper Alloys in Iron and Steel Industry. Proceedings of the Seminar Held in Calcutta, August 18, 1978.  

National Technical Information Service (NTIS)

Various papers presented at the seminar covered the following topics: Use of Copper in Integrated Iron and Steel works; Copper Base Components in Iron & Steel Industries - Problems and Prospects in India; Steel Plant Requirements of High Conductivity Copp...

1978-01-01

103

Temporal and spatial variations of copper, cadmium, lead, and zinc in Ten Mile Creek in South Florida, USA.  

PubMed

Lead (Pb), zinc (Zn), copper (Cu), and cadmium (Cd) often seriously deteriorate water quality. Spatial and temporal fluctuations of the metal concentrations in the Ten Mile Creek (Florida) (TMC) were monitored on a weekly basis at 7 sampling sites, from June 2005 to September 2007. River sediment samples were also collected from these sites in April, June, and October 2006 and January 2007, and analyzed for water, Mehlich 1 (M1), and Mehlich 3 (M3)-extractable metals (Mehlich, 1953, 1984), to examine the role of sediments as sources or sinks of the metals. The concentrations of lead, zinc, copper, and cadmium in the water samples were copper (2.53 microg/L), and cadmium (copper, and 0.25 microg/L for cadmium), pulse concentrations of the metals significantly exceeded these limits. Correlations of lead, zinc, copper, and cadmium concentrations in the TMC to other environmental factors, including the results of principal component analysis, suggest that there are different sources of metals. These sources include surface runoff from agricultural lands or urban wastewater, geological backgrounds, and tidal flow. Water-, M1-, and M3-extractable lead, zinc, copper, and cadmium concentrations in river sediments indicate the possibility that river sediment serves as an internal source of the metals for the TMC. This hypothesis was supported by positive correlations between concentrations of copper, lead, and zinc in the river water and their respective water-extractable concentrations in the sediments. PMID:19280898

Yang, Yuangen; He, Zhenli; Lin, Youjian; Phlips, Edward J; Stoffella, Peter J; Powell, Charles A

2009-01-01

104

Nuclear magnetic resonance of iron and copper disease states  

SciTech Connect

The tissue levels of paramagnetic ions are an important factor in the determination of T/sub 1/ values as observed by nuclear magnetic resonance (NMR) imaging. The increased levels of iron present in human disease states such as hemochromatosis lead to decreased T/sub 1/ values. The mean liver T/sub 1/ of three patients with iron storage disease was determined to be 130 msec, significantly different from the value of 154 msec, the mean for 14 normal controls. Whether NMR will be able to detect the increased copper levels in liver and brain in Wilson disease remains for further clinical trials to evaluate. NMR imaging, however, does serve as a noninvasive method for the diagnosis of states of iron overload and as a technique to follow progression of disease or response to medical therapy.

Runge, V.M. (Vanderbilt Univ., Nashville, TN); Clanton, J.A.; Smith, F.W.; Hutchison, J.; Mallard, J.; Partain, C.L.; James, A.E. Jr.

1983-11-01

105

Copper Deficiency in Sheep with High Liver Iron Accumulation  

PubMed Central

An outbreak of enzootic ataxia among sheep raised in the northeastern region of Brazil is described. Copper (Cu) deficiency was diagnosed in a herd of 56 sheep, among which five presented characteristic clinical symptoms of enzootic ataxia. The symptoms began 30 days after birth, with a clinical condition that included locomotion difficulty, limb ataxia, tremors, and continual falls. Liver biopsies were performed and blood was collected to determine hepatic and plasmatic Cu, iron (Fe), and zinc (Zn) concentration, respectively. The laboratory results showed that the animals presented low copper concentrations in the plasma and liver, without difference between the clinically healthy animals and those affected by enzootic ataxia. Even after supplementation with adequate Cu levels had been recommended, it was found on a new visit to the farm four months later that one animal still presented a clinical condition and that the hepatic Cu levels of the herd had not risen. Despite the low copper content of the diet, the high hepatic Fe levels found suggest that antagonism due to this element may have been an important factor in triggering copper deficiency in these animals, and thus, additional copper supplementation may be necessary for these animals.

de Sousa, Isadora Karolina Freitas; Hamad Minervino, Antonio Humberto; Sousa, Rejane dos Santos; Chaves, Dowglish Ferreira; Barros, Isabella de Oliveira; de Araujo, Carolina Akiko Sato Cabral; Junior, Raimundo Alves Barreto; Ortolani, Enrico Lippi

2012-01-01

106

Mild copper deficiency alters gene expression of proteins involved in iron metabolism  

Microsoft Academic Search

Iron and copper homeostasis share common proteins and are therefore closely linked to each other. For example, copper-containing proteins like ceruloplasmin and hephaestin oxidize Fe2+ during cellular export processes for transport in the circulation bound to transferrin. Indeed, copper deficiency provokes iron metabolism disorders leading to anemia and liver iron accumulation.The aim of the present work was to understand the

Sylvain Auclair; Christine Feillet-Coudray; Charles Coudray; Susanne Schneider; Martina U. Muckenthaler; Andrzej Mazur

2006-01-01

107

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

PubMed

Non-accumulated metals in mixed metal contaminated soils may affect hyperaccumulator growth and metal accumulation and thus remediation efficiency. Two hydroponics experiments were conducted to investigate the effects of copper (Cu) on cadmium (Cd) and zinc (Zn) accumulation by the Cd/Zn hyperaccumulator Sedum plumbizincicola, Cu toxicity and plant detoxification using chemical sequential extraction of metals, sub-cellular separation, micro synchrotron radiation based X-ray fluorescence, and transmission electron microscopy. Compared with the control (0.31 ?M Cu), 5-50 ?M Cu had no significant effect on Cd/Zn accumulation, but Cu at 200 ?M induced root cell plasmolysis and disordered chloroplast structure. The plants held Cu in the roots and cell walls and complexed Cu in insoluble forms as their main detoxification mechanisms. Exposure to 200 ?M Cu for 4 days inhibited plant Cd uptake and translocation but did not affect Zn concentrations in roots and stems. Moreover, unloading of Cd and Zn from stem to leaf was restrained compared to control plants, perhaps due to Cu accumulation in leaf veins. Copper may thus interfere with root Cd uptake and restrain Cd/Zn unloading to the leaves. Further investigation of how Cu affects plant metal uptake may help elucidate the Cd/Zn hyper-accumulating mechanisms of S. plumbizincicola. PMID:23959253

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

2013-10-15

108

Cadmium, chromium, copper, and zinc in rice and rice field soil from southern Catalonia, Spain  

Microsoft Academic Search

Metals are ubiquitous in the modem industrialized environment. Some metals have no beneficial effects in humans. In contrast, other metals such as chromium, copper, zinc, manganese, cobalt or iron are essential for man. However, these essential trace elements can also be dangerous at high levels. Many metals are natural constituents of soils, whereas soils may also be contaminated by a

M. Schuhmacher; J. L. Domingo; J. M. Llobet; J. Corbella

1994-01-01

109

Promotion of atherogenesis by copper or iron-Which is more likely?  

SciTech Connect

Iron levels increase in atherosclerotic lesions in cholesterol fed-rabbits and play a role in atherosclerosis. We investigated whether copper also rises. Male New Zealand White rabbits were fed high-cholesterol diets for 8 weeks. After sacrifice, lesion sizes were determined, and elemental analyses of the lesion and unaffected artery wall performed using nuclear microscopy. Unlike iron, lesion copper is decreased by about half compared with the unaffected artery wall, and much less copper than iron is present. Our data suggest that iron may be more likely to play a role in the promotion of atherosclerosis than copper.

Rajendran, Reshmi [Centre for Ion Beam Applications, Department of Physics, National University of Singapore, MD7, 8 Medical Drive, Singapore 117597 (Singapore); Department of Biochemistry, National University of Singapore, MD7, 8 Medical Drive, Singapore 117597 (Singapore); Ren, Minqin [Centre for Ion Beam Applications, Department of Physics, National University of Singapore, MD7, 8 Medical Drive, Singapore 117597 (Singapore); Ning, Pan [Department of Biochemistry, National University of Singapore, MD7, 8 Medical Drive, Singapore 117597 (Singapore); Tan Kwong Huat, Benny [Department of Pharmacology, National University of Singapore, MD7, 8 Medical Drive, Singapore 117597 (Singapore); Halliwell, Barry [Department of Biochemistry, National University of Singapore, MD7, 8 Medical Drive, Singapore 117597 (Singapore)]. E-mail: bchbh@nus.edu.sg; Watt, Frank [Centre for Ion Beam Applications, Department of Physics, National University of Singapore, MD7, 8 Medical Drive, Singapore 117597 (Singapore)

2007-02-02

110

Evidence for iron, copper and zinc complexation as multinuclear sulphide clusters in oxic rivers  

PubMed

The availability and toxicity of trace metals in fresh water are known to be regulated by the complexation of free metal ions with dissolved organic matter. The potential role of inorganic sulphides in binding trace metals has been largely ignored because of the reduced persistence of sulphides in these oxic waters. However, nanomolar concentrations of copper and zinc sulphides have been observed in four rivers in Connecticut and Maryland. Here we report dissolved (< 0.2 microm particle diameter) sulphide concentrations ranging up to 600 nM, with more than 90% being complexed by copper, iron and zinc. These complexes account for up to 20% of the total dissolved Fe and Zn and 45% of the total dissolved Cu. Fourier transform mass spectrometry reveals that these complexes are not simple M(HS)+ protonated species but are higher-order unprotonated clusters (M3S3, M4S6, M2S4), similar to those found in laboratory solutions and bio-inorganic molecules. These extended structures have high stability constants and are resistant to oxidation and dissociation, which may help control the toxicity of these and other less abundant, but more toxic, trace metals, such as silver, cadmium and mercury. PMID:10972287

Rozan; Lassman; Ridge; Luther

2000-08-24

111

Comparative Pulmonary Absorption, Distribution, and Toxicity of Copper Gallium Diselenide, Copper Indium Diselenide, and Cadmium Telluride in Sprague–Dawley Rats  

Microsoft Academic Search

Copper gallium diselenide (CGS), copper indium diselenide (CIS), and cadmium telluride (CdTe) are novel compounds used in the photovoltaic and semiconductor industries. This study was conducted to characterize the relative toxicities of these compounds and to evaluate the pulmonary absorption and distribution after intratracheal instillation. Female Sprague–Dawley rats were administered a single equimolar dose (70 mm) of CGS (21 mg\\/kg),

Daniel L. Morgan; Cassandra J. Shines; Shawn P. Jeter; Mark E. Blazka; Michael R. Elwell; Ralph E. Wilson; Sandra M. Ward; Herman C. Price; Paul D. Moskowitz

1997-01-01

112

Iron and copper homeostasis and intestinal absorption using the Caco2 cell model.  

PubMed

Whole body homeostasis can be viewed as the balance between absorption and excretion, which can be regulated independently. Present evidence suggests that for iron, intestinal absorption is the main site for homeostatic regulation, while for copper it is biliary excretion. There are connections between iron and copper in intestinal absorption and transport. The blue copper plasma protein, ceruloplasmin, and its intracellular homologue, hephaestin, play a role in cellular iron release. The studies reviewed here compare effects of Fe(II) and Cu(II) on their uptake and overall transport by monolayers of polarized Caco2 cells, which model intestinal mucosa. In the physiological range of concentrations, depletion of cellular iron or copper (by half) increased uptake of both metal ions. Depletion of iron or copper also enhanced overall transport of iron from the apical to the basal chamber. Copper depletion enhanced overall copper transport, but iron depletion did not. Pretreatment with excess copper also stimulated copper absorption. Plasma ceruloplasmin (added to the basal chamber) failed to enhance basolateral iron release, and Zn(II) failed to compete with Cu(II) for uptake. Neither copper nor iron deficiency altered expression of IREG1 or DMT1 (-IRE form) at the mRNA level. Thus, in the low-normal range of iron and copper availability, intestinal absorption of both metals appears to be positively related to the need for these elements by the whole organism. The two metal ions also influenced each other's transport; but with copper excess, other mechanisms come into play. PMID:12572674

Linder, Maria C; Zerounian, Nora R; Moriya, Mizue; Malpe, Rashmi

2003-03-01

113

Recovery of iron from copper slag by deep reduction and magnetic beneficiation  

NASA Astrophysics Data System (ADS)

Aiming at recovering iron from high-iron-content copper slag, this article introduced a combination technology of deep reduction and magnetic beneficiation, investigated the iron recovery efficiency and optimized the technical conditions. When coke powder with 86wt% fixed carbon was used as a reductant, iron was successfully extracted from the copper slag. Under the optimized condition of the coke powder content of 14wt%, the calcium-to-silicon mass ratio (Ca/Si) of 0.2, the roasting temperature of 1300°C, the roasting time of 3 h, the grinding time of 20 min, and the magnetic field intensity of 61 kA·m-1, the iron recovery rate of the copper slag can reach 91.82%, and the extracted iron powder has an iron grade of 96.21%. With the characteristics of high iron grade and low impurity content, the extracted iron powder can be used as high-quality raw materials of weathering steel.

Li, Ke-qing; Ping, Shuo; Wang, Hong-yu; Ni, Wen

2013-11-01

114

Specific features of photoluminescence properties of copper-doped cadmium selenide quantum dots  

SciTech Connect

The effect of doping with copper on the photoluminescence properties of cadmium selenide quantum dots 4 nm in dimension is studied. The quenching of the excitonic photoluminescence band related to the quantum dots and the appearance of an impurity photoluminescence band in the near-infrared region are observed after doping of the quantum dots with copper. It is established that, on doping of the quantum dots, the photoluminescence kinetics undergoes substantial changes. The photoluminescence kinetics of the undoped quantum dots is adequately described by a sum of exponential relaxation relations, whereas the photoluminescence kinetics experimentally observed in the region of the impurity band of the copper-doped samples follows stretched exponential decay, with the average lifetimes 0.3-0.6 {mu}s at the photon energies in the range of 1.47-1.82 eV. The experimentally observed changes in the photoluminescence properties are attributed to transformation of radiative centers in the quantum dots when doped with copper atoms.

Tselikov, G. I., E-mail: gleb@vega.phys.msu.ru [Moscow State University, Faculty of Physics (Russian Federation); Dorofeev, S. G.; Tananaev, P. N. [Moscow State University, Faculty of Chemistry (Russian Federation); Timoshenko, V. Yu. [Moscow State University, Faculty of Physics (Russian Federation)

2011-09-15

115

Kinetics and thermodynamics of cadmium ion removal by adsorption onto nano zerovalent iron particles  

Microsoft Academic Search

Nano zerovalent iron (nZVI) is an effective adsorbent for removing various organic and inorganic contaminants. In this study, nZVI particles were used to investigate the removal of Cd2+ in the concentration range of 25–450mgL?1. The effect of temperature on kinetics and equilibrium of cadmium sorption on nZVI particles was thoroughly examined. Consistent with an endothermic reaction, an increase in the

Hardiljeet K. Boparai; Meera Joseph; Denis M. O’Carroll

2011-01-01

116

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

EPA Science Inventory

Tetra sulfide silane coated iron-copper nano-particle aggregates are found to be potentially very high capacity sorbents for vapor phase mercury capture. High equilibrium capacities were obtained for the silane coated iron copper nano-aggregate sorbent at 70 oC and 120 oC. Even a...

117

A novel iron- and copper-binding protein in the Lyme disease spirochaete.  

PubMed

Iron and copper are transition metals that can be toxic to cells due to their abilities to react with peroxide to generate hydroxyl radical. Ferritins and metallothioneins are known to sequester intracellular iron and copper respectively. The Lyme disease pathogen Borrelia burgdorferi does not require iron, but its genome encodes a ferritin-like Dps (DNA-binding protein from starved bacteria) molecule, which has been shown to be important for the spirochaete's persistence in the tick and subsequent transmission to a new host. Here, we show that the carboxyl-terminal cysteine-rich (CCR) domain of this protein functions as a copper-binding metallothionein. This novel fusion between Dps and metallothionein is unique to and conserved in all Borrelia species. We term this molecule BicA for Borrelia iron- and copper-binding protein A. An isogenic mutant lacking BicA had significantly reduced levels of iron and copper and was more sensitive to iron and copper toxicity than its parental strain. Supplementation of the medium with iron or copper rendered the spirochaete more susceptible to peroxide killing. These data suggest that an important function of BicA is to detoxify excess iron and copper the spirochaete may encounter during its natural life cycle through a tick vector and a vertebrate host. PMID:23061404

Wang, Peng; Lutton, Anthony; Olesik, John; Vali, Hojatollah; Li, Xin

2012-12-01

118

Solid Solution, Mass Transport, and Crystal Growth Studies of Cadmium Iron Selenide.  

NASA Astrophysics Data System (ADS)

Cadmium iron selenide, a semimagnetic semiconductor, has been investigated. Solid solubilities of iron in CdSe were determined at temperatures between 650^ circC and 1100^circC, using the X-ray diffraction Debye-Scherrer powder technique. The solubility limits of Fe in CdSe increase with the temperatures to reach a maximum of about 19.5 mole % FeSe_ {1.24} at 925^circ C, and then decrease with further increasing temperature. Solidification phenomena of the Cd-Fe-Se solid solutions were observed employing optical microscopy, which reveals a typical divorced, eutectic type, nonequilibrium solidification. The combination of the X-ray diffraction and the microscopic investigations yielded a pseudo-binary, eutectic type phase diagram of the Cd-Fe-Se system. Partial pressures of the major vapor species in the Cd-Fe-Se physical and the Cd-Fe-Se-Iodine chemical vapor transport systems were calculated. The partial pressure of gaseous iron species of the PVT system may be neglected compared to those of Cd and Se_2^ecies. This suggests that cadmium iron selenide crystals cannot be grown by the PVT method. For the PVT experiments, using the as-synthesized (CdSe)_ {0.90}(FeSe_{1.24})_{0.10 } source materials, crystals with compositions of 6-8 mole % FeSe_{1.24} were grown at a source temperature of 1000^ circC and a DeltaT of 12^circC. These result are contradictory to the thermodynamic predictions, and were further investigated employing specially purified source materials. Iron contents in the crystals grown in these experiments are close to zero. The transport of iron in the initial mass transport experiments may be due to the chemical impurities (most likely the metal chlorides) in the as-synthesized source materials. Mass transport experiments of the Cd-Fe-Se-Iodine CVT system were performed as a function of source temperatures, the degrees of undercooling (DeltaT), and initial iodine pressures. Promising parameters for the growth of cadmium iron selenide single crystals by the CVT method, e.g., the source temperatures of 800-850 ^circC, initial iodine pressures of 0.5-1.0 atm, and DeltaT of 10 -20^circC, were established. Mass fluxes of cadmium iron selenide were computed using a one -dimensional diffusion equation. The overall trends of the computed mass flux as a function of growth conditions are consistent with the experimental results. However, differences between the theoretical and experimental mass fluxes may be due to the uncertainties of the thermochemical data used and the approximations made in these estimations. Single crystals of cadmium iron selenide with compositions of 6.5-8.5 mole % FeSe_{1.24 } and of about 5 mm edge lengths were successfully grown from the (CdSe)_{0.90 }(FeSe_{1.24})_{0.10} source materials by the CVT method. Compositions of various portions of the bulk crystals are nearly constant along its axis within the error limits, indicating that the crystals possess reasonable compositional uniformity. The indices of the crystal surfaces were obtained by the X -ray diffraction Laue method. The (0001) and (1011) planes usually developed as the natural facets on the surfaces, and (1010) and(1120) as the cleavage planes. A promising chemical etchant for cadmium iron selenide crystals was developed, consisting of about 20 vol. % concentrated HNO_3, 60 vol. % glacial CH _3COOH, and 20 vol. % concentrated H _2SO_4 acids. Etch pit densities of the grown crystals are in the range of 5times10 ^4-rm5times10^5/cm ^2..

Huang, Xuejun

119

Simultaneous Determination of Copper, Lead, and Cadmium at Hexagonal Mesoporous Silica Immobilized Quercetin Modified Carbon Paste Electrode  

PubMed Central

A new method was developed for simultaneous determination of copper, lead, and cadmium, based on their voltammetric response at a carbon paste electrode modified with hexagonal mesoporous silica (HMS) immobilized quercetin (HMS-Qu/CPE). Compared with quercetin modified carbon paste electrode (Qu/CPE) and quercetin ionic liquid modified carbon paste electrode (Qu-IL/CPE), the HMS-Qu/CPE exhibited improved selectivity and high sensitivity toward the detection of copper, lead, and cadmium. The properties of the HMS-Qu/CPE in 0.1?M HCOONa-HCl buffer solution (pH4.7) were investigated by adsorptive stripping voltammetry (ASV) and electrochemical impedance spectroscopy (EIS). The electrochemical behavior of copper, lead, and cadmium at the modified electrodes and factors affecting the preconcentration procedures were also investigated. Detection limits of 5.0, 0.8, 1.0?nM for copper, lead, and cadmium were obtained, respectively. The method is simple, fast, sensitive, and selective, and is successfully applied to soil sample.

Xia, Fangquan; Zhang, Xin; Zhou, Changli; Sun, Danzi; Dong, Yanmin; Liu, Zhen

2010-01-01

120

Comparative strategies of heavy metal accumulation by crustaceans: zinc, copper and cadmium in a decapod, an amphipod and a barnacle  

Microsoft Academic Search

This study investigates the comparative strategies of accumulation under standardised laboratory conditions of the essential metals zinc and copper, and the non-essential metal cadmium by three crustaceans of different taxa; vizPalaemon elegans Rathke (Malacostraca: Eucarida: Decapoda),Echinogammarus pirloti (Sexton & Spooner) (Malacostraca: Peracarida: Amphipoda) and the barnacleElminius modestus Darwin (Cirripedia: Thoracica).

P. S. Rainbow; S. L. White

1989-01-01

121

ANODIC STRIPPING VOLTAMMETRY AT A MERCURY FILM ELECTRODE: BASELINE CONCENTRATIONS OF CADMIUM, LEAD, AND COPPER IN SELECTED NATURAL WATERS  

EPA Science Inventory

A simple, rapid, and inexpensive anodic stripping voltammetric method with a mercury thin film electrode is reported for the establishment of baseline concentrations of cadmium, lead, and copper in natural waters. The procedure for routine surface preparation of wax-impregnated g...

122

Total Cadmium, Copper, and Zinc in Two Dreissenid Mussels, Dreissena polymorpha and Dreissena bugensis, at the Outflow of Lake Ontario  

Microsoft Academic Search

Two closely related Dreissenid mussel species, Dreissena polymorpha and Dreissena bugensis, both recent invaders of the Great Lakes and St. Lawrence River, have potential as biological monitors of metal contamination. To better understand their usefulness as biomonitors, we measured total cadmium, copper, and zinc concentrations in soft tissues of both species at a site at the outflow of Lake Ontario.

Carolyn Johns; Briana E. Timmerman

1998-01-01

123

Effects of pH on the Toxicities of Cadmium, Copper, and Zinc to Steelhead Trout ('Salmo gairdneri') (Journal Version).  

National Technical Information Service (NTIS)

Increased metal concentrations have been associated with freshwater acidification. Continuous-flow acute toxicity tests were conducted in soft water to determine the effect of pH on the toxicity of cadmium, copper, and zinc to small (1-6 g) steelhead trou...

R. F. Cusimano D. F. Brakke G. A. Chapman

1986-01-01

124

Biosorption of lead(II), cadmium(II), copper(II) and nickel(II) by anaerobic granular biomass  

Microsoft Academic Search

Biosorption is potentially an attractive technology for treatment of wastewater for retaining heavy metals from dilute solutions. This study investigated the feasibility of anaerobic granules as a novel type of biosorbent, for lead, copper, cadmium, and nickel removal from aqueous solutions. Anaerobic sludge supplied from a wastewater treatment plant in the province of Quebec was used. Anaerobic granules are microbial

Alaa H. Hawari; Catherine N. Mulligan

2006-01-01

125

Biosorption of cadmium, copper and lead by isolated mother cell walls and whole cells of Chlorella fusca  

Microsoft Academic Search

Using a new method for the isolation of released mother cell walls of Chlorella fusca, the biosorption of cadmium, copper and lead by purified cell wall isolates and whole cell suspensions was comparatively characterized. In all cases whole cells accumulated more metal ions than isolated cell walls. Both the Langmuir and Freundlich isotherm models were suitable for describing the short-term

B. Wehrheim; M. Wettern

1994-01-01

126

Binary adsorption of copper(II) and cadmium(II) from aqueous solutions by biomass of marine alga Durvillaea potatorum  

SciTech Connect

Much work on the biosorption of heavy metals by low-cost, natural biomass has been on the uptake of single metals. In practice, wastewaters often contain multiple heavy metal ions. In this paper the binary adsorption of copper(II) and cadmium(II) by a pretreated biomass of the marine alga Durvillaea potatorum from aqueous solutions was studied. The results showed that the uptake capacities for each heavy metal of the binary system were lower when compared with the single metal biosorption for copper and cadmium, respectively, but the total capacities for the binary system were similar to those obtained for single metal biosorption. The uptake capacities for copper and cadmium increased as the equilibrium pH increased and reached a plateau at a pH around 5.0. The uptake process was relatively fast, with 90% of the adsorption completed within 10 minutes for copper and 30 minutes for cadmium, and equilibrium reached after about 60 minutes of stirring. The biosorption isotherms of binary systems were not significantly affected by equilibrium temperature. The presence of light metal ions in solution also did not affect adsorption significantly. The binary adsorption was successfully predicted by the extended Langmuir model, using parameters and capacities obtained from single component systems.

Yu, Q.; Kaewsarn, P. [Griffith Univ., Nathan, Queensland (Australia). School of Environmental Engineering

1999-06-01

127

Copper-Dependent Iron Assimilation Pathway in the Model Photosynthetic Eukaryote Chlamydomonas reinhardtii  

PubMed Central

The unicellular green alga Chlamydomonas reinhardtii is a valuable model for studying metal metabolism in a photosynthetic background. A search of the Chlamydomonas expressed sequence tag database led to the identification of several components that form a copper-dependent iron assimilation pathway related to the high-affinity iron uptake pathway defined originally for Saccharomyces cerevisiae. They include a multicopper ferroxidase (encoded by Fox1), an iron permease (encoded by Ftr1), a copper chaperone (encoded by Atx1), and a copper-transporting ATPase. A cDNA, Fer1, encoding ferritin for iron storage also was identified. Expression analysis demonstrated that Fox1 and Ftr1 were coordinately induced by iron deficiency, as were Atx1 and Fer1, although to lesser extents. In addition, Fox1 abundance was regulated at the posttranscriptional level by copper availability. Each component exhibited sequence relationship with its yeast, mammalian, or plant counterparts to various degrees; Atx1 of C. reinhardtii is also functionally related with respect to copper chaperone and antioxidant activities. Fox1 is most highly related to the mammalian homologues hephaestin and ceruloplasmin; its occurrence and pattern of expression in Chlamydomonas indicate, for the first time, a role for copper in iron assimilation in a photosynthetic species. Nevertheless, growth of C. reinhardtii under copper- and iron-limiting conditions showed that, unlike the situation in yeast and mammals, where copper deficiency results in a secondary iron deficiency, copper-deficient Chlamydomonas cells do not exhibit symptoms of iron deficiency. We propose the existence of a copper-independent iron assimilation pathway in this organism.

La Fontaine, Sharon; Quinn, Jeanette M.; Nakamoto, Stacie S.; Page, M. Dudley; Gohre, Vera; Moseley, Jeffrey L.; Kropat, Janette; Merchant, Sabeeha

2002-01-01

128

Experimental study of methanol synthesis catalysts containing copper plated iron fibers  

Microsoft Academic Search

An experimental study was conducted which evaluated the performance of methanol synthesis catalysts containing copper plated, polycrystalline iron fibers. The active catalyst material was comprised of Cu\\/ZnO\\/AlâOâ with atomic ratio, Cu\\/Zn\\/Al = 6\\/3\\/1. It was necessary to copper plate the iron fibers since iron catalyzes the more thermodynamically favorable synthesis of methane from CO, COâ, and Hâ. A deposition by

Bieser; A. L. Jr

1983-01-01

129

Decomposition of the sulfates of copper, iron (II), iron (III), nickel, and zinc: XPS, SEM, DRIFTS, XRD, and TGA study  

Microsoft Academic Search

The bulk and surface characteristics during decomposition of the transition metal sulfates of copper, iron (II), iron (III), nickel, and zinc are investigated utilizing various spectroscopic techniques. An oxidized form of sulfur was detected on the surface during decomposition of all metal sulfate samples, except zinc sulfate. Surface characteristics were not necessarily representative of the bulk characteristics. Oxy-sulfate was observed

Ranjani V Siriwardane; James A Poston Jr; Edward P Fisher; Ming-Shing Shen; Angela L Miltz

1999-01-01

130

Metagenomic analysis of cadmium and copper resistance genes in activated sludge of a tannery wastewater treatment plant.  

PubMed

In order to comprehensively characterize the copper and cadmium resistance in activated sludge of a tannery wastewater treatment plant, a resistance protein database of the two heavy metals was manually created by retrieving annotated sequences and related information from the public databases and published literatures. The metagenomic DNA was extracted from the activated sludge for Illumina high-throughput sequencing, and the obtained 11,973,394 clean reads (1.61 Gb) were compared against the established databases using BLAST tool. Annotations of the BLAST hits showed that 222 reads (0.019 per thousand) and 197 reads (0.016 per thousand) were identified as copper and cadmium resistance genes, respectively. Among the identified cadmium resistance genes, czcA encoding cobalt-zinc-cadmium resistance protein had the highest abundance (83 reads, 0.0069 per thousand), which was further confirmed by annotation of the open reading frames predicted with the assembly contigs. Among the copper resistance genes, copA (66 reads, 0.0055 per thousand) was most abundant, followed by copK and cusR. Alignment against the Clusters of Orthologous Groups (COG) database also suggested that 87.26% of the matched reads were grouped in COG0474 (cation transport ATPase). This study may be practically helpful for exploring various functional genes in the environment using high-throughput sequencing and bioinformatics methods. PMID:24620608

Jia, Shuyu; Wang, Zhu; Zhang, Xu-Xiang; Liu, Bo; Li, Weixin; Cheng, Shupei

2013-04-01

131

Removal of copper from carbon-saturated steel with an aluminum sulfide/iron sulfide slag  

SciTech Connect

Scrap iron and steel has long been considered a resource in the steel-making industry, and its value is largely determined by its impurity content. As the mini-mills, the major consumers of scrap iron and steel, expand into producing flat-rolled sheet, the demand for high-quality scrap will increase. Of the impurities present in scrap, copper is particularly troublesome because of its role in causing hot shortness. Therefore, the copper content of scrap should be kept below {approx} 0.1 wt%. A method for removing copper from steel could be used to improve the quality of scrap and make it more available for use by mini-mills. To determine the effectiveness of a binary slag consisting of aluminum sulfide and iron sulfide on the removal of copper from steel and iron, the distribution coefficient of copper between the slag and a carbon-saturated iron melt was investigated at 1,365 C. The composition of the slag was varied from nearly pure aluminum sulfide to pure iron sulfide. A maximum distribution coefficient of 30 was found, and the copper level in the iron melt was reduced to as low as 0.07 wt.% with a 4:1 ratio of iron to slag.

Cohen, A.; Blander, M.

1995-12-01

132

Arabidopsis thaliana nicotianamine synthase 4 is required for proper response to iron deficiency and to cadmium exposure.  

PubMed

The nicotianamine synthase (NAS) enzymes catalyze the formation of nicotianamine (NA), a non-proteinogenic amino acid involved in iron homeostasis. We undertook the functional characterization of AtNAS4, the fourth member of the Arabidopsis thaliana NAS gene family. A mutant carrying a T-DNA insertion in AtNAS4 (atnas4), as well as lines overexpressing AtNAS4 both in the atnas4 and the wild-type genetic backgrounds, were used to decipher the role of AtNAS4 in NA synthesis, iron homeostasis and the plant response to iron deficiency or cadmium supply. We showed that AtNAS4 is an important source for NA. Whereas atnas4 had normal growth in iron-sufficient medium, it displayed a reduced accumulation of ferritins and exhibited a hypersensitivity to iron deficiency. This phenotype was rescued in the complemented lines. Under iron deficiency, atnas4 displayed a lower expression of the iron uptake-related genes IRT1 and FRO2 as well as a reduced ferric reductase activity. Atnas4 plants also showed an enhanced sensitivity to cadmium while the transgenic plants overexpressing AtNAS4 were more tolerant. Collectively, our data, together with recent studies, support the hypothesis that AtNAS4 displays an important role in iron distribution and is required for proper response to iron deficiency and to cadmium supply. PMID:23759098

Koen, Emmanuel; Besson-Bard, Angélique; Duc, Céline; Astier, Jérémy; Gravot, Antoine; Richaud, Pierre; Lamotte, Olivier; Boucherez, Jossia; Gaymard, Frédéric; Wendehenne, David

2013-08-01

133

Variability of cadmium, copper and zinc levels in molluscs and associated sediments from Chile.  

PubMed

The concentrations of cadmium, copper and zinc in mussel and sediment samples collected together from eight different geographical coastal areas of Chile were determined. The mussels studied were 'Chorito Maico', 'Almejas' and 'Navajuelas Chilenas' (Perumytilus purpuratus, Semelle solida and Tagellus dombeii, respectively). Sampling was carried out in July and September 1992 and January and April 1993 (winter, spring, summer and autumn seasons in Chile, respectively). The metal levels in these mussels varied among species; there were several sites where the metal concentrations in molluscs approached or exceeded the criteria levels for Cd, Cu and Zn in shellfish products: 1, 10 and 50 ppm ww respectively, which are regarded as safe levels for human consumption. The results of metal levels in sediments showed two areas clearly polluted with Cu. Strong relationships between Cu concentrations in the three molluscs and sediments were found; weak correlations were observed for Zn in S. solida. PMID:15091389

De Gregori, I; Pinochet, H; Gras, N; Muñoz, L

1996-01-01

134

10% conversion efficiency in thin film polycrystalline cadmium-zinc sulfide/copper sulfide solar cells  

NASA Astrophysics Data System (ADS)

Thin film cadmium-zinc sulfide/copper sulfide solar cells have been developed with conversion efficiencies greater than 10% in direct sunlight. The development of these cells was based on decreasing the electron affinity mismatch between the Cu2S and CdS and thereby raising the open-circuit voltage above that achievable with the standard CdS/Cu2S solar cell. The electron affinity of the CdS was reduced by the incorporation of Zn by the co-evaporation of CdS and ZnS. With improved preparation of Cd(1-x)Zn(x)S (with x between .1 and .2) films, and the same process that produced Cu2S/CdS cells with efficiencies in excess of 9%, the increased open-circuit voltage has led to efficiencies greater than 10%.

Hall, R. B.; Birkmire, R. W.; Phillips, J. E.; Meakin, J. D.

135

Field screening of chromium, cadmium, zinc, copper, and lead in sediments by stripping analysis  

SciTech Connect

Stripping analysis (SA) was successfully employed for field verification of metals contaminants in soils and sediments at hazardous waste sites. Microwave digestion procedures were tailored to meet the needs of field activities and electrochemical measurements. An adsorptive stripping voltammetric (AdSV) scheme was used for monitoring total chromium and for chromium speciation, while conventional anodic stripping voltammetry (ASV) and potentiometric stripping analysis (PSA) were used for measuring cadmium, zinc, copper, and lead. The results demonstrate that SA is capable of on-site identification of contaminated layers in soils and sediments. Concentration values measured by SA correlated well with those obtained by U.S. Environmental Protection Agency (EPA)-approved atomic or mass spectroscopy methods. The remarkable sensitivity, portability, low-power need, and low cost of SA make it an attractive choice for on-site analysis of selected metals during site characterization and remediation activities. 12 refs., 6 figs., 2 tabs.

Olsen, K.B. (Pacific Northwest Lab., Richland, WA (United States)); Wang, J.; Setladji, R.; Lu, J. (New Mexico State Univ., Las Cruces, NM (United States))

1994-11-01

136

Simultaneous Measurement of Zinc, Copper, Lead and Cadmium in Baby Weaning Food and Powder Milk by DPASV.  

PubMed

Apart from the breast milk, infant formula and baby weaning food have a special role in infant diet. Infants and young children are very susceptible to amount of trace elements. Copper and zinc are two elements that add in infant food. Lead and cadmium are heavy metals that enter to food chain unavoidably. DPASV is a benefit and applicable method for measurement of trace elements in food products. In this study, concentration of zinc, copper, lead and cadmium in four brands of baby food (rice and wheat based) and powder milk was analyzed with DPASV and polarograph set. Total Mean ± SE of zinc, copper, lead and cadmium in baby foods (n = 240) were 11.86 ± 1.474 mg/100g, 508.197 ± 83.154 ?g/100g, 0.445 ± 0.006, 0.050 ± 0.005 mg/Kg respectively. Also these amount in powder milk (n = 240) were 3.621± 0.529 mg/100g, 403.822 ± 133.953 ?g/100g, 0.007 ± 0.003, 0.060 ± 0.040 mg/Kg respectively. Zinc level in baby food type I was higher than lablled value (P = 0.030), but in other brands was not difference. Concentration of copper in all of samples was in labeled range (P > 0.05). In each four products, level of lead and cadmium were lower than the standard limit (P < 0.05). Amount of zinc and lead in baby food I, had difference versus other products. Concentration of zinc, camium in baby food type I, was higher than type II (P = 0.043, 0.001 respectively). Concentration of lead and cadmium in baby food type II, was higher than infant formulas, but are in standard limit. PMID:24734090

Sadeghi, Naficeh; Oveisi, Mohammad Reza; Jannat, Behrooz; Hajimahmoodi, Mannan; Behfar, Abdolazim; Behzad, Masoomeh; Norouzi, Narges; Oveisi, Morvarid; Jannat, Behzad

2014-01-01

137

Simultaneous Measurement of Zinc, Copper, Lead and Cadmium in Baby Weaning Food and Powder Milk by DPASV  

PubMed Central

Apart from the breast milk, infant formula and baby weaning food have a special role in infant diet. Infants and young children are very susceptible to amount of trace elements. Copper and zinc are two elements that add in infant food. Lead and cadmium are heavy metals that enter to food chain unavoidably. DPASV is a benefit and applicable method for measurement of trace elements in food products. In this study, concentration of zinc, copper, lead and cadmium in four brands of baby food (rice and wheat based) and powder milk was analyzed with DPASV and polarograph set. Total Mean ± SE of zinc, copper, lead and cadmium in baby foods (n = 240) were 11.86 ± 1.474 mg/100g, 508.197 ± 83.154 ?g/100g, 0.445 ± 0.006, 0.050 ± 0.005 mg/Kg respectively. Also these amount in powder milk (n = 240) were 3.621± 0.529 mg/100g, 403.822 ± 133.953 ?g/100g, 0.007 ± 0.003, 0.060 ± 0.040 mg/Kg respectively. Zinc level in baby food type I was higher than lablled value (P = 0.030), but in other brands was not difference. Concentration of copper in all of samples was in labeled range (P > 0.05). In each four products, level of lead and cadmium were lower than the standard limit (P < 0.05). Amount of zinc and lead in baby food I, had difference versus other products. Concentration of zinc, camium in baby food type I, was higher than type II (P = 0.043, 0.001 respectively). Concentration of lead and cadmium in baby food type II, was higher than infant formulas, but are in standard limit.

Sadeghi, Naficeh; Oveisi, Mohammad Reza; Jannat, Behrooz; Hajimahmoodi, Mannan; Behfar, Abdolazim; Behzad, Masoomeh; Norouzi, Narges; Oveisi, Morvarid; Jannat, Behzad

2014-01-01

138

Cadmium Accumulation and Its Effects on Uptake of Micronutrients in Indian Mustard [Brassica juncea (L.) Czern.] Grown in a Loamy Sand Soil Artificially Contaminated with Cadmium  

Microsoft Academic Search

A pot experiment was conducted in a greenhouse to evaluate the effects of different levels of cadmium (Cd) on Cd accumulation and their effects on uptake of micronutrients in Indian mustard [Brassica juncea (L.) Czern.]. Cadmium accumulation in shoots and interactions among other metals [manganese (Mn), iron (Fe), copper (Cu), and zinc (Zn)] were investigated. Ten levels of Cd ranging

R. Sikka; V. Nayyar

2012-01-01

139

Removal of copper from aqueous solution using iron-containing adsorbents derived from methane fermentation sludge.  

PubMed

Iron-containing adsorbents prepared from methane fermentation sludge (MFS) were characterized by N(2) adsorption, XRD, SEM, EDX, pH determination and elemental analysis. The experiments for copper removal from aqueous solution using the MFS-derived adsorbents were performed, and the effects of iron content, forms of the iron (hydr)oxides, surface basicity and pH of the aqueous solution on copper removal were elucidated respectively. The desorption studies were also performed and the mechanism of Cu(II) adsorption was proposed. The results indicated that the adsorbent obtained at 700 degrees C for 1h in a steam atmosphere possessed the highest capability for Cu(II) adsorption. The high copper removal ability of the MFS-derived materials is attributed to their intermediate surface area, strong surface basicity and the presence of iron (hydr)oxides on their surface. The Cu(II) adsorption onto the composite adsorbents is via ion-exchange with H, Ca and K ions, surface precipitation and binding with active sites on the surface of iron (hydr)oxides at various pH values. The desorption of copper in deionized water is quite low. The irreversibility of copper adsorption on the iron-containing adsorbents is attributed to the formation of strong bonds between Cu(II) and the iron (hydr)oxides. The adsorbent can be applied to remove copper from water or soil by fixation onto the surface. PMID:19726131

Qian, Qingrong; Mochidzuki, Kazuhiro; Fujii, Takao; Sakoda, Akiyoshi

2009-12-30

140

Acclimation and Deacclimation of Brown Trout (Salmo trutta) to Zinc and Copper Singly and in Combination with Cadmium or Copper.  

PubMed

Brown trout (Salmo trutta) were chronically exposed to low and high levels of zinc (Zn) alone, copper (Cu) alone, a Zn-Cu mixture, and a Zn-cadmium (Cd) mixture all starting with eyed eggs and continuing through to the fingerling stage. Exposure to the metals and metal mixtures resulted in acclimation as measured by greater median lethal concentrations (LC50) values relative to metal-naïve fry. The degree of acclimation was similar between the low and high exposures except for Cu, where acclimation was observed at the high but not the low acclimation level. The increases in tolerance relative to metal-naïve controls were usually less than a factor of 2 and never exceeded a factor of 3. Acclimation exposures did not affect hatch or survival except for the high-acclimation regime of Zn plus Cu. Acclimation came at an apparent metabolic cost because growth was decreased by most acclimation exposures. Deacclimation, as evidenced by a return of LC50 values to naïve levels, occurred after 2-5 weeks in clean water. PMID:24770996

Brinkman, Stephen F; Woodling, John D

2014-08-01

141

Serum iron, copper and zinc status in maternal and cord blood.  

PubMed

Pregnancy is associated with increased demand of all the nutrients like Iron, Copper, Zinc etc. and deficiency of any of these could affect pregnancy, delivery and out come of pregnancy. With this consideration, the study was conducted on 80 mothers and newborns and 20 age matched control women. Out of 80 mothers, 34 had Iron deficiency anemia and their Hb levels were below 9.0 gm/d(1). Pregnant women had significantly lower Iron and Zinc levels while Copper and Total Iron Binding Capacity (TIBC) were significantly higher (P<0.001). Newborns had significantly elevated Iron and Zinc levels and low levels of Copper and TIBC as compared to their mothers irrespective of Iron deficiency anemia. Micronutrient status of newborn was found to be dependent on their mother's micronutrient status. Besides, results also suggest micronutrient interactions, which are reflected in Iron/Zinc, Iron/Copper and Zinc/Copper ratios. In view of this, there is need for proper, adequate and balanced micronutrient supplementation during pregnancy to affect a healthy outcome. PMID:23105456

Upadhyaya, Chitra; Mishra, Sandhya; Ajmera, Peeyush; Sharma, Praveen

2004-07-01

142

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 ...

143

Electron paramagnetic resonance spectroscopic study of copper hopping in doped bis(L-histidinato)cadmium dihydrate.  

PubMed

Electron paramagnetic resonance (EPR) spectroscopy was used to study Cu(II) dynamic behavior in a doped biological model crystal, bis(L-histidinato)cadmium dihydrate, in order to gain better insight into copper site stability in metalloproteins. Temperature-dependent changes in the low temperature X-band EPR spectra became visible around 100 K and continued up to room temperature. The measured 298 K g-tensor (principal values: 2.17, 2.16, 2.07) and copper hyperfine coupling tensor (principal values: -260, -190, -37 MHz) were similar to the average of the 77 K tensor values pertaining to two neighboring histidine binding sites. The observed temperature dependence was interpreted using Anderson's theory of motional narrowing, where the magnetic parameters for the different states are averaged as the copper rapidly hops between sites. The EPR pattern was also found to undergo a sharp sigmoidal-shaped, temperature-dependent conversion between two species with a critical temperature T(c) ? 160 K. The species below T(c) hops between the two low temperature site patterns, and the one above T(c) represents an average of the molecular spin Hamiltonian coupling tensors of the two 77 K sites. In addition, the low and high temperature species hop between one another, contributing to the dynamic averaging. Spectral simulations using this 4-state model determined a hop rate between the two low temperature sites ?(h4) = 4.5 × 10(8) s(-1) and between the low and high temperature states ?(h2) = 1.7 × 10(8) s(-1) at 160 K. An Arrhenius relationship of hop rate and temperature gave energy barriers of ?E4 = 389 cm(-1) and ?E2 = 656 cm(-1) between the two low temperature sites and between the low and high temperature states, respectively. PMID:23530765

Colaneri, Michael J; Vitali, Jacqueline; Kirschbaum, Kristin

2013-04-25

144

Determination of silver, bismuth, cadmium, copper, lead, and zinc in geologic materials by atomic absorption spectrometry with tricaprylylmethylammonium chloride  

USGS Publications Warehouse

Interferences commonly encountered in the determination of silver, bismuth, cadmium, copper, lead, and zinc at crustal abundance levels are effectively eliminated using a rapid, sensitive, organic extraction technique. A potassium chlorate-hydrochloric acid digestion solubilizes the metals not tightly bound in the silicate lattice of rocks, soils, and stream sediments. The six metals are selectively extracted into a 10% Aliquat 336-MIBK organic phase in the presence of ascorbic acid and potassium iodide. Metals in the organic extract are determined by flame atomic absorption spectrometry to the 0.02-ppm level for silver, cadmium, copper, and zinc and to the 0.2-ppm level for bismuth and lead with a maximum relative standard deviation of 18.8% for known reference samples. An additional hydrofluoric acid digestion may be used to determine metals substituted in the silicate lattice.

Viets, J. G.

1978-01-01

145

Single, binary and multi-component adsorption of copper and cadmium from aqueous solutions on Kraft lignin—a biosorbent  

Microsoft Academic Search

A new biosorbent for removing toxic metal ions from water\\/industrial wastewater has been investigated using by-product lignin from paper production. Lignin was extracted from black liquor waste, characterized and utilized for the removal of copper and cadmium from aqueous solutions in single, binary and multi-component systems. Adsorption studies were conducted at different temperatures, lignin particle sizes, pHs and solid to

Dinesh Mohan; Charles U. Pittman; Philip H. Steele

2006-01-01

146

Comparison of cadmium and copper effect on phenolic metabolism, mineral nutrients and stress-related parameters in Matricaria chamomilla plants  

Microsoft Academic Search

Cadmium and copper uptake and its consequence for activity of selected enzymes of phenolic metabolism, phenolic acids accumulation,\\u000a quantity of mineral nutrients and stress-related parameters in Matricaria chamomilla plants exposed to 60 ?M and 120 ?M for 7 days has been studied. Cu content in the above-ground biomass was ca. 10-fold lower\\u000a compared to Cd and amount of Cd in the methanol-soluble fraction

Jozef Ková?ik; Bo?ivoj Klejdus; Josef Hedbavny; František Štork; Martin Ba?kor

2009-01-01

147

Synthesis and thermal decomposition of freeze-dried copper–iron formates  

Microsoft Academic Search

The thermal decomposition of freeze-dried formate precursors for copper–iron oxides was investigated by means of DTA, TG, mass spectroscopy and X-ray powder diffractometry. The freeze-dried copper formate is crystalline. Its decomposition at about 200°C releases formic acid (HCOOH) and carbon dioxide (CO2) as main primary gaseous decomposition products beside metallic copper as a solid product. However, the decomposition of the

F. Kenfack; H. Langbein

2005-01-01

148

Iron, cadmium, and chromium in seagrass (Thalassia testudinum) from a coastal nature reserve in karstic Yucatán.  

PubMed

The management of protected areas in karstic regions is a challenge because flooded cave systems form there and provide underground hydrological conducts that may link different zones. As a consequence, affectations to the protected areas can possibly occur as a consequence of human activities in remote areas and may therefore pass undetected. Thus, the monitoring of possible contaminants in these regions is becoming imperative. In this work, we analyze the concentration of essential (iron) and non-essential metals (cadmium and chromium) in the seagrass Thalassia testudinum that grows in Yalahau Lagoon, located in a near-to-pristine protected area of the Yucatán Peninsula, close to the rapidly developing touristic belt of the Mexican Caribbean. Salinity and silicate patterns show that Yalahau is an evaporation lagoon, where groundwater discharge is important. High iron (> 400 ?g/g), cadmium (>4 ?g/g), and chromium (? 1 ?g/g) concentrations were found in the area of highest groundwater input of the lagoon. High levels (5.1 ?g/g) were also found near the town dump. In the rest of the sampling sites, metal concentrations remained near to background levels as estimated from other works. Temporal changes of concentrations in the seagrass tissues show also a local input and an input from the groundwater that could provoke an environmental problem in the Yalahau Lagoon in the near future. PMID:23404548

Avelar, Mayra; Bonilla-Heredia, Blanca; Merino-Ibarra, Martín; Herrera-Silveira, Jorge A; Ramirez, Javier; Rosas, Humberto; Valdespino, Job; Carricart-Ganivet, Juan P; Martínez, Ana

2013-09-01

149

Influences of petroleum on accumulation of copper and cadmium in the polychaete Nereis diversicolor.  

PubMed

Using the exposure simulation experiment, the action of petroleum affecting the accumulation of the trace metals including copper (Cu) and cadmium (Cd) in littoral polychaete Nereis diversicolor collected from the Shuangtaizi Estuary in Liaoning Province, China was examined. The results showed that there was a markedly non-linear relationship between the accumulation of Cu in worms and the experimental concentration of Cu in exposure solutions when the concentration of petroleum remained at 0, 100, and 220 microl/L, respectively. However, significantly non-linear relationship for worms exposed to Cd was observed only when the concentration of added petroleum was 0 and 220 microl/L. The accumulation of Cu in worms did not differ significantly among the three different levels of petroleum concentrations combined with various concentrations of Cu. So was the accumulation of Cd in worms (p > 0.05). However, the addition of petroleum in exposure solutions brought about an increase in the accumulation of Cu in Nereis diversicolor, in comparison with single Cu pollution. On the other hand, when the concentration of added petroleum remained at 100 microl/L, the accumulation of Cd in worms was lower than that in worms exposed to various concentrations of only cadmium. However, the worms exposed to Cd and petroleum 220 microl/L did not show obvious and identical increase in the accumulation of Cd, compared with single Cd exposure. The accumulation of both Cu and Cd in worms did not increase significantly with the increases in concentrations of Cu or Cd in exposure solutions combined with petroleum (0, 100, and 220 microl/L) under the experimental conditions. Although Nereis diversicolor is exposed to very high Cu and Cd in exposure solutions, accumulation and detoxification mechanisms are sufficient to cope with the extra metal influx in order to survive. PMID:20050557

Sun, Fu-Hong; Zhou, Qi-Xing; Zhang, Qian-Ru

2006-01-01

150

Magnetic Studies of Solid Solutions II. The Properties of Quenched Copper-Iron Alloys  

Microsoft Academic Search

The alloys of copper and iron which have been studied show unusual magnetic properties both in the saturation effects at low temperatures and in the apparent change in the magnetic moment of the dissolved iron atoms over the range of temperatures from 14°K to 1300°K. Further research is required on other alloy systems containing transition elements dissolved in the noble

F. Bitter; A. R. Kaufmann; C. Starr; S. T. Pan

1941-01-01

151

Kinetics of solution of hydrogen in liquid iron, nickel, and copper containing dissolved oxygen and sulfur  

Microsoft Academic Search

An investigation of the effect of surface active oxygen and sulfur on the rate of hydrogen solution in inductively stirred liquid iron, nickel, and copper was made using a modified constant-volume Sieverts' method. The overall and initial rates of hydrogen solution in liquid iron and nickel were found to decrease with increasing oxygen content in concentration ranges found in the

W. M. Small; R. H. Radzilowski; R. D. Pehlke

1973-01-01

152

Iron and copper as virulence modulators in human fungal pathogens.  

PubMed

Fungal pathogens have evolved sophisticated machinery to precisely balance the fine line between acquiring essential metals and defending against metal toxicity. Iron and copper are essential metals for many processes in both fungal pathogens and their mammalian hosts, but reduce viability when present in excess. However, during infection, the host uses these two metals differently. Fe has a long-standing history of influencing virulence in pathogenic fungi, mostly in regards to Fe acquisition. Numerous studies demonstrate the requirement of the Fe acquisition pathway of Candida, Cryptococcus and Aspergillus for successful systemic infection. Fe is not free in the host, but is associated with Fe-binding proteins, leading fungi to develop mechanisms to interact with and to acquire Fe from these Fe-bound proteins. Cu is also essential for cell growth and development. Essential Cu-binding proteins include Fe transporters, superoxide dismutase (SOD) and cytochrome c oxidase. Although Cu acquisition plays critical roles in fungal survival in the host, recent work has revealed that Cu detoxification is extremely important. Here, we review fungal responses to altered metal conditions presented by the host, contrast the roles of Fe and Cu during infection, and outline the critical roles of fungal metal homeostasis machinery at the host-pathogen axis. PMID:24851950

Ding, Chen; Festa, Richard A; Sun, Tian-Shu; Wang, Zhan-You

2014-07-01

153

Iron, Manganese and Copper Release from Synthetic Hydroxyapatite  

NASA Technical Reports Server (NTRS)

Kinetic stir-flow dissolution experiments were performed on iron- (Fe-SHA), manganese- (Mn-SHA), and copper- (Cu-SHA) containing synthetic hydroxyapatites. Solution treatments consisted of de-ionized water, citric acid and DTPA. Initially, Mn concentrations were higher than Cu concentrations and Fe concentrations were the lowest in all treatments. At later times Mn and Cu concentrations dropped in the DTPA treatment while Fe rose to the concentration similar to Mn and Cu. At all times, metal release concentrations in the water and citric acid treatments followed the trend of Mn>Cu>Fe. Rietveld analysis of x-ray diffraction data and ^31P NMR indicated that the metals substituted for Ca in the SHA structure. However, EPR data suggested that a metal (hydr)oxide phase existed either on the SHA surface or between the SHA crystallites. The metal concentration trend of Mn>Cu>Fe suggested that the initial solution metal concentrations are dependent on the dissolution of (hydr)oxides from SHA surfaces or between SHA crystallites. Similar metal concentrations at later times in the DTPA experiments suggests that metal concentrations were controlled by the release of Mn, Cu, or Fe from the SHA structure.

Sutter, B.; Hossner, L. R.; Ming, Douglas W.

1999-01-01

154

Use of Cement Copper in an Iron-Copper-Carbon Powder Metallurgy Alloy.  

National Technical Information Service (NTIS)

An investigation was made of the substitution of cement copper powder for commercial copper powder in an Fe-7 pct Cu-1 pct C powder metallurgy alloy. Copper powders from six different commercial cementation operations were separately upgraded by screening...

R. L. Crosby D. H. Desy R. M. Doerr

1970-01-01

155

Assessment of copper, cadmium and zinc remobilization in Mediterranean marine coastal sediments  

NASA Astrophysics Data System (ADS)

The remobilization of copper, cadmium and zinc in sediments of three selected coastal microenvironments of the Aegean Sea (Eastern Mediterranean) is assessed. Various analytical methods and techniques were employed providing concentrations, profiles and forms of metals and organic matter in sediments and pore waters. At Loutropyrgos, a non-industrial site located, however, within an intensively industrialized enclosed gulf, an intense resupply of zinc in pore water from sediment was recorded, correlating with the highest value of weakly bound fraction of zinc determined at this area. The comparatively high zinc concentrations measured in the pore waters (394 nM), exceed considerably those in the overlying seawater (12.5 nM determined by DGT; 13.5 nM total), resulting in the formation of a strong concentration gradient at the sediment-water interface. Potential zinc flux at the sediment-water interface at Loutropyrgos (based on 0.4 mm DGT profile) was calculated equal to 0.8 mmol.m -2.d -1. The half lives of trace metals at Loutropyrgos site, based on the aforementioned DGT profiles, amount to 0.1 y (Zn), 2.8 y (Cd), 4.5 y (Cu), 2.2 y (Mn) and 0.4 y (Fe) pointing out to the reactivity of these metals at the sediment-water interface. The concentration of dissolved organic carbon (DOC) in pore waters of the three selected sites (2.7-5.2 mg/L) was up to four times higher compared to that of the corresponding overlying seawater. Similarly, the concentrations of carbohydrates in pore waters (0.20-0.91 mg/L monosaccharides; 0.71-1.6 mg/L polysaccharides) are an order of magnitude higher than those of seawater, forming a concentration gradient at the sediment-water interface. Total carbohydrates contribute between 34 and 48% of the organic carbon of the pore waters, being significantly higher than those of seawater from the corresponding areas, which were in the range of 15-21%. The complexing capacity as for copper ions (CCu) determined in pore water ranges widely, from 0.03 ?M at Kalamos to 3.76 ?M at Molos, whereas the corresponding values for cadmium ions (CCd) were non detectable, except for Kalamos site, where the value for CCd was equal to 0.03 ?M. A significant increase in the values of CCu, normalized as for DOC, was observed in pore waters in relation to those of overlying seawater. This indicates an 'enrichment' of pore waters in dissolved organic ligands for copper ions per unit of DOC. Up to 72% of DOC could be present as ligands capable to complex copper ions.

Sakellari, Aikaterini; Plavši?, Marta; Karavoltsos, Sotiris; Dassenakis, Manos; Scoullos, Michael

2011-01-01

156

Iron deposition at mineralization fronts and osteoid formation following chronic cadmium exposure in ovariectomized rats.  

PubMed

To investigate whether chronic exposure of cadmium (Cd) chloride induces osteomalacic lesions similar to Itai-itai disease (IID), ovariectomized rats were injected intravenously with the cadmium at doses of 0.05 and 0.5 mg/kg/day, 5 days per week, for 50 weeks. In six rats in the 0.5 mg/kg group, the administration was continued for up to 70 weeks. In the 0.5 mg/kg group, the plasma concentration of calcium was similar in the treatment and control groups throughout the treatment period. The urinary excretion of calcium increased from 20 weeks and the increase became marked from 40 weeks. Histopathologically, osteoid seams in the femur, tibia, and humerus were increased from 50 weeks, and these changes became prominent at 70 weeks. Hypertrophy and hyperplasia of chief cells in the parathyroid were also observed from 50 weeks. The osteoid morphometry of the trabecular bone of the femur and sternum revealed a dose-dependent increase in osteoid/bone volumes. Roentgenographs of the antebrachial and metacarpal bones taken at 70 weeks showed so-called paper bone. The bone Cd content markedly increased until 25 weeks, but thereafter decreased linearly for up to 70 weeks. In contrast to the Cd content, the iron content decreased until 25 weeks, but thereafter increased until 70 weeks. Undecalcified section of the humerus showed the deposition of iron and formation of osteoid at mineralization fronts. Our data suggest that osteomalacic lesions were caused by chronic Cd intoxication, and that iron, as well as Cd, was involved in osteoid formation. PMID:9144451

Hiratsuka, H; Katsuta, O; Toyota, N; Tsuchitani, M; Akiba, T; Marumo, F; Umemura, T

1997-04-01

157

Low iron stores are related to higher blood concentrations of manganese, cobalt and cadmium in non-smoking, Norwegian women in the HUNT 2 study  

SciTech Connect

Low iron (Fe) stores may influence absorption or transport of divalent metals in blood. To obtain more knowledge about such associations, the divalent metal ions cadmium (Cd), manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn) and lead (Pb) and parameters of Fe metabolism (serum ferritin, haemoglobin (Hb) and transferrin) were investigated in 448 healthy, menstruating non-smoking women, age 20-55 years (mean 38 years), participating in the Norwegian HUNT 2 study. The study population was stratified for serum ferritin: 257 were iron-depleted (serum ferritin <12 {mu}g/L) and 84 had iron deficiency anaemia (serum ferritin <12 {mu}g/L and Hb<120 g/L). The low ferritin group had increased blood concentrations of Mn, Co and Cd but normal concentrations of Cu, Zn and Pb. In multiple regression models, ferritin emerged as the main determinant of Mn, Co and Cd (p<0.001), while no significant associations with Cu, Zn and Pb were found. Adjusted r{sup 2} for the models were 0.28, 0.48 and 0.34, respectively. Strong positive associations between blood concentrations of Mn, Co and Cd were observed, also when controlled for their common association with ferritin. Apart from these associations, the models showed no significant interactions between the six divalent metals studied. Very mild anaemia (110{<=}Hb<120 g/L) did not seem to have any effect independent of low ferritin. Approximately 26% of the women with iron deficiency anaemia had high concentrations of all of Mn, Co and Cd as opposed to 2.3% of iron-replete subjects. The results confirm that low serum ferritin may have an impact on body kinetics of certain divalent metal ions, but not all. Only a fraction of women with low iron status exhibited an increased blood concentration of divalent metals, providing indication of complexities in the body's handling of these metals.

Margrete Meltzer, Helle, E-mail: helle.margrete.meltzer@fhi.no [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Lise Brantsaeter, Anne [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway)] [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Borch-Iohnsen, Berit [Institute of Basic Medical Sciences, Department of Nutrition, University of Oslo, PO Box 1046 Blindern, N-0316 Oslo (Norway)] [Institute of Basic Medical Sciences, Department of Nutrition, University of Oslo, PO Box 1046 Blindern, N-0316 Oslo (Norway); Ellingsen, Dag G. [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway)] [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway); Alexander, Jan [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway)] [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Thomassen, Yngvar [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway)] [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway); Stigum, Hein [Division of Epidemiology, Department of Chronic Diseases, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway)] [Division of Epidemiology, Department of Chronic Diseases, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Ydersbond, Trond A. [Statistics Norway, P.Box 8131 Dep, N-0033 Oslo (Norway)] [Statistics Norway, P.Box 8131 Dep, N-0033 Oslo (Norway)

2010-07-15

158

Influence of indigenous and added iron on copper extraction from soil.  

PubMed

Experimental tests of copper leaching from a low permeability soil are presented and discussed. The objective of the experiments was to investigate the influence of indigenous and added iron in the soil towards copper mobilization. Metals' leaching was performed by flushing (column tests) or washing (batch tests) the soil with an aqueous solution of ethylenediaminetetraacetic acid, EDTA. An excess of EDTA was used in flushing tests (up to a EDTA:Cu molar ratio of about 26.2:1), while, in washing tests, the investigated EDTA vs. copper molar ratios were in the range between 1 (equimolar tests) and 8. Copper extraction yield in flushing tests (up to about 85%) was found to depend upon contact time between the soil and the leaching solution and the characteristics of the conditioning solution. The saturation of the soil with a NaNO(3) solution before the treatment, favoured the flushing process reducing the time of percolation, but resulted in a lower metal extraction during the following percolation of EDTA. The indigenous iron was competitive with copper to form EDTA complexes only when it was present in the organic and oxides-hydroxides fractions. Artificial iron addition to the soil resulted in an increase of both the exchangeable iron and the iron bonded to the organic fraction of the soil, thus increasing the overall amount of iron available to extraction. In both batch and continuous tests, the mechanism of copper extraction was found to involve the former dissolution of metal salts, that lead to an initial high concentration of both copper and selected competitive cations (essentially Ca(2+)), and the following EDTA exchange reaction between calcium and copper complexes. The initial metal salts dissolution was found to be pH-dependant. PMID:19477586

Di Palma, Luca

2009-10-15

159

Combined effect of copper, cadmium, and lead upon Cucumis sativus growth and bioaccumulation.  

PubMed

Cucumis sativus (cucumber) was tested to assess an ecotoxicity in soils contaminated by the heavy metals copper (Cu), cadmium (Cd), and lead (Pb) separately and in combinations. The toxicity endpoint was plant growth, which was measured as shoot and root lengths after 5 day exposure. Sum of toxic unit (TU) at 50% inhibition for the mixture (EC50mix) was calculated from the dose (TU-based)-response relationships by the Trimmed Spearman-Karber method. Binary metal combinations of Cu+Cd, Cu+Pb, and Cd+Pb produced all three types of interactions; concentration additive (EC50mix=1TU), synergistic (EC50mix<1TU), and antagonistic (EC50mix>1TU) responses. Ternary combination of Cu+Cd+Pb produced an antagonistic response for the growth of Cucumis sativus. Bioaccumulations of Cu, Cd, and Pb were observed in Cucumis sativus and the bioaccumulation of one metal was influenced by the presence of other metals in metal mixtures. In general, antagonistic and/or synergistic responses reflected bioaccumulation patterns in some binary combinations, but the patterns in mixtures were not always consistent with toxicity data. This study indicated that TU approach appears to be a good model to estimate the combined effect of metals in plant systems, and mixture toxicity may be closely-related to the bioaccumulation pattern within plants. Combined effects of mixtures have to be taken into account to ecological risk assessment. PMID:15142768

An, Youn-Joo; Kim, Young-Mi; Kwon, Tae-Im; Jeong, Seung-Woo

2004-06-29

160

Comparison of extractants for plant-available zinc, cadmium, nickel, and copper in contaminated soils  

SciTech Connect

The objective of this study was to find a suitable extractant(s) for plant-available metals in metal contaminated soils. Swiss chard (Beta vulgaris L. Fordhook Giant) was grown in greenhouse pots on 46 Ontario soils varying in degree of contamination with metals. The soils had been contaminated with metals to varying degrees over a period of years. After 40 days, the plants were harvested and Zn, Cd, Ni, and Cu concentrations were measured. Each soil was extracted with nine different extractants: aqua regia, 0.01M EDTA, 0.005M DTPA, 0.02M NTA, 0.5N CH/sub 3/COOH, 1N CH/sub 3/COONH/sub 4/, 0.6N HCl + 0.05N AlCl/sub 3/, (COOH)/sub 2/ + (COONH/sub 4/)/sub 2/, and H/sub 2/O. Zinc, cadmium, nickel, and copper concentrations in Swiss chard were correlated with the amounts of soil Zn, Cd, Ni, and Cu removed by each extractant. Of the nine soil extractants, CH/sub 3/COONH/sub 4/ was the best predictor of plant-available Zn if only extractable Zn and soil pH were included as independent variables in a regression equation. Acetic acid was the best extractant for prediction of both plant-available Cd and Ni when soil pH was included in the equation. Attempts to find a suitable soil extractant for plant-available Cu were unsuccessful.

Haq, A.U.; Bates, T.E.; Soon, Y.K.

1980-07-01

161

Oxidative status of Matricaria chamomilla plants related to cadmium and copper uptake.  

PubMed

Cadmium (Cd) and copper (Cu) uptake by the plants of Matricaria chamomilla and relation to activities of guaiacol peroxidase (GPX, EC 1.11.1.7), catalase (CAT, EC 1.11.1.6) and glutathione reductase (GR, EC 1.6.4.2) up to 7 days of exposure to 3, 60 and 120 microM Cd or Cu was studied. Cd content in rosettes was ca. 10-fold higher in comparison to Cu while Cu was preferentially accumulated in the roots. In line with this observation, increase of CAT and GPX activity was similar in rosettes of Cd and Cu-treated plants, indicating non-redox active properties of Cd and low Cu accumulation. In the roots, Cu showed strong pro-oxidant effect, as judged from extreme stimulation of CAT and GPX, followed by increase of hydrogen peroxide and malondialdehyde. However, GPX seemed to be more important for alleviation of oxidative stress (ca. 93-250-fold higher activity in 120 microM Cu-treated roots). Cd had substantially lower influences and stimulated GR activity more than Cu. Activities of hydrogen peroxide-scavenging enzymes in relation to its accumulation are also discussed. PMID:18389371

Kovácik, Jozef; Backor, Martin

2008-08-01

162

Competitive biosorption of lead, cadmium, copper, and arsenic ions using algae.  

PubMed

The present study aims to evaluate the competitive biosorption of lead, cadmium, copper, and arsenic ions by using native algae. A series of experiments were carried out in a batch reactor to obtain equilibrium data for adsorption of single, binary, ternary, and quaternary metal solutions. The biosorption of these metals is based on ion exchange mechanism accompanied by the release of light metals such as calcium, magnesium, and sodium. Experimental parameters such as pH, initial metal concentrations, and temperature were studied. The optimum pH found for removal were 5 for Cd(2+) and As(3+) and 3 and 4 for Pb(2+) and Cu(2+), respectively. Fourier transformation infrared spectroscopy analysis was used to find the effects of functional groups of algae in biosorption process. The results showed that Pb(2+) made a greater change in the functional groups of algal biomass due to high affinity to this metal. An ion exchange model was found suitable for describing the biosorption process. The affinity constants sequence calculated for single system was K Pb > K Cu > K Cd > K As; these values reduced in binary, ternary, and quaternary systems. In addition, the experimental data showed that the biosorption of the four metals fitted well the pseudo-second-order kinetics model. PMID:23054774

Sulaymon, Abbas H; Mohammed, Ahmed A; Al-Musawi, Tariq J

2013-05-01

163

The cellular redox state as a modulator in cadmium and copper responses in Arabidopsis thaliana seedlings.  

PubMed

The cellular redox state is an important determinant of metal phytotoxicity. In this study we investigated the influence of cadmium (Cd) and copper (Cu) stress on the cellular redox balance in relation to oxidative signalling and damage in Arabidopsis thaliana. Both metals were easily taken up by the roots, but the translocation to the aboveground parts was restricted to Cd stress. In the roots, Cu directly induced an oxidative burst, whereas enzymatic ROS (reactive oxygen species) production via NADPH oxidases seems important in oxidative stress caused by Cd. Furthermore, in the roots, the glutathione metabolism plays a crucial role in controlling the gene regulation of the antioxidative defence mechanism under Cd stress. Metal-specific alterations were also noticed with regard to the microRNA regulation of CuZnSOD gene expression in both roots and leaves. The appearance of lipid peroxidation is dual: it can be an indication of oxidative damage as well as an indication of oxidative signalling as lipoxygenases are induced after metal exposure and are initial enzymes in oxylipin biosynthesis. In conclusion, the metal-induced cellular redox imbalance is strongly dependent on the chemical properties of the metal and the plant organ considered. The stress intensity determines its involvement in downstream responses in relation to oxidative damage or signalling. PMID:20828869

Cuypers, Ann; Smeets, Karen; Ruytinx, Jos; Opdenakker, Kelly; Keunen, Els; Remans, Tony; Horemans, Nele; Vanhoudt, Nathalie; Van Sanden, Suzy; Van Belleghem, Frank; Guisez, Yves; Colpaert, Jan; Vangronsveld, Jaco

2011-03-01

164

Comparison of early transcriptome responses to copper and cadmium in rice roots.  

PubMed

The phytotoxic effects of copper (Cu) and cadmium (Cd) on plant growth are well documented. However, Cu and Cd toxicity targets and the cellular systems contributing to acquisition of tolerance are not fully understood at the molecular level. We aimed to identify genes and pathways that discriminate the actions of Cu and Cd in rice roots (Oryza sativa L. cv. TN67). The transcripts of 1,450 and 1,172 genes were regulated after Cu and Cd treatments, respectively. We identified 882 genes specifically respond to Cu treatment, and 604 unique genes as Cd-responsive by comparison of expression profiles of these two regulated gene groups. Gene ontology analysis for 538 genes involved in primary metabolism, oxidation reduction and response to stimulus was changed in response to both metals. In the individual aspect, Cu specifically altered levels of genes involved in vesicle trafficking transport, fatty acid metabolism and cellular component biogenesis. Cd-regulated genes related to unfolded protein binding and sulfate assimilation. To further characterize the functions of vesicle trafficking transport under Cu stress, interference of excytosis in root tissues was conducted by inhibitors and silencing of Exo70 genes. It was demonstrated that vesicle-trafficking is required for mediation of Cu-induced reactive oxygen species (ROS) production in root tissues. These results may provide new insights into understanding the molecular basis of the early metal stress response in plants. PMID:23400832

Lin, Chung-Yi; Trinh, Ngoc Nam; Fu, Shih-Feng; Hsiung, Yu-Chyuan; Chia, Li-Chiao; Lin, Chung-Wen; Huang, Hao-Jen

2013-03-01

165

Effect of zinc supplementation on the antioxidant, copper, and iron status of physically active adolescents.  

PubMed

Puberty associated with intense physical activity results in oxidation stress. Zinc supplementation may benefit antioxidant capacity although it may also affect iron and copper status. This study evaluated the effect of zinc supplementation on antioxidant, zinc and copper status of physically active male football players (13 years +/- 0.4 years), divided in two groups and studied during 12 weeks: Zn-supplemented (Zn-SUP, 22 mg Zn d(-1) as zinc gluconate, n = 21) and placebo (PLA, n = 26). At baseline, there was no significant difference in biochemical indices between the two groups. After treatment, plasma zinc and erythrocyte iron increased in both groups (p < 0.001); urinary zinc increased (p < 0.001) only in Zn-SUP, and erythrocyte zinc decreased (p = 0.002) only in PLA. Plasma iron and copper decreased (p = 0.01 and p = 0.015, respectively) only in Zn-SUP. Plasma ferric-reducing ability and plasma conjugated dienes increased, and erythrocyte osmotic fragility decrease in both groups, although the latter two were significantly lower in Zn-SUP compared to PLA (p < 0.01). In conclusion, our study indicates that the use of 22 mg d(-1) of supplemental zinc during 12 week in adolescent athletes did not affect growth, improved markers of antioxidant status but reduced plasma iron and copper. Therefore, it appears that the use of zinc supplementation by healthy adolescent athletes benefits their antioxidant capacity but impairs copper and iron nutritional status. PMID:19277992

de Oliveira, Karla de Jesus Fernandes; Donangelo, Carmen Marino; de Oliveira, Astrogildo Vianna; da Silveira, Carmen Lucia Porto; Koury, Josely Correa

2009-04-01

166

Role of the iron transporter OsNRAMP1 in cadmium uptake and accumulation in rice.  

PubMed

The heavy metal cadmium (Cd) is toxic to humans, and its accumulation in rice grains is a major agricultural problem. Rice has seven putative metal transporter NRAMP genes, but microarray analysis showed that only OsNRAMP1 is highly up-regulated by iron (Fe) deficiency. OsNRAMP1 localized to the plasma membrane and transported Cd as well as Fe. OsNRAMP1 expression was observed mainly in roots and was higher in the roots of a high-Cd-accumulating cultivar (Habataki) than in those of a low-Cd-accumulating cultivar (Sasanishiki). The amino acid sequence of OsNRAMP1 in the Sasanishiki and Habataki cultivars was found to be 100% identical. These results suggest that OsNRAMP1 participates in cellular Cd uptake and that the differences observed in Cd accumulation among cultivars are because of differences in OsNRAMP1 expression levels in roots. PMID:22067109

Takahashi, Ryuichi; Ishimaru, Yasuhiro; Nakanishi, Hiromi; Nishizawa, Naoko K

2011-11-01

167

Complexation and Toxicity of Copper in Higher Plants. II. Different Mechanisms for Copper versus Cadmium Detoxification in the Copper-Sensitive Cadmium/Zinc Hyperaccumulator Thlaspi caerulescens (Ganges Ecotype)1[OA  

PubMed Central

The cadmium/zinc hyperaccumulator Thlaspi caerulescens is sensitive toward copper (Cu) toxicity, which is a problem for phytoremediation of soils with mixed contamination. Cu levels in T. caerulescens grown with 10 ?m Cu2+ remained in the nonaccumulator range (<50 ppm), and most individuals were as sensitive toward Cu as the related nonaccumulator Thlaspi fendleri. Obviously, hyperaccumulation and metal resistance are highly metal specific. Cu-induced inhibition of photosynthesis followed the “sun reaction” type of damage, with inhibition of the photosystem II reaction center charge separation and the water-splitting complex. A few individuals of T. caerulescens were more Cu resistant. Compared with Cu-sensitive individuals, they recovered faster from inhibition, at least partially by enhanced repair of chlorophyll-protein complexes but not by exclusion, since the content of Cu in their shoots was increased by about 25%. Extended x-ray absorption fine structure (EXAFS) measurements on frozen-hydrated leaf samples revealed that a large proportion of Cu in T. caerulescens is bound by sulfur ligands. This is in contrast to the known binding environment of cadmium and zinc in the same species, which is dominated by oxygen ligands. Clearly, hyperaccumulators detoxify hyperaccumulated metals differently compared with nonaccumulated metals. Furthermore, strong features in the Cu-EXAFS spectra ascribed to metal-metal contributions were found, in particular in the Cu-resistant specimens. Some of these features may be due to Cu binding to metallothioneins, but a larger proportion seems to result from biomineralization, most likely Cu(II) oxalate and Cu(II) oxides. Additional contributions in the EXAFS spectra indicate complexation of Cu(II) by the nonproteogenic amino acid nicotianamine, which has a very high affinity for Cu(II) as further characterized here.

Mijovilovich, Ana; Leitenmaier, Barbara; Meyer-Klaucke, Wolfram; Kroneck, Peter M.H.; Gotz, Birgit; Kupper, Hendrik

2009-01-01

168

Electrochemical stripping determination of traces of copper, lead, cadmium and zinc in zirconium metal and zirconium dioxide.  

PubMed

Procedures have been developed for the determination of copper, lead, cadmium and zinc in zirconium metal and zirconium dioxide, at concentrations of 1 ppm or less. Zirconium metal was dissolved in suphuric acid, and zirconium dioxide decomposed under pressure with hydrofluoric acid. Sample solutions were prepared in dilute sulphuric acid. For the stripping determination, the sample solution was either mixed with a complexing tartrate base electrolyte or the pre-electrolysis was carried out in acid solution, with the acid solution being exchanged for a pure base electrolyte (e.g. an acetate buffer) for the stripping step. The stripping step was monitored by d.c., differential pulse and Kalousek commutator voltammetry and the three methods were compared. A stationary mercury-drop electrode can generally be used for all the methods, whereas a mercury-film electrode is suitable only for the d.c. voltammetric determination of copper, lead and cadmium, as pulse measurements with films are poorly reproducible and the electrodes are easily damaged. The relative standard deviation does not exceed 20%. Some samples contained relatively large amounts of copper, which is best separated by electrodeposition on a platinum electrode. PMID:18962277

Stulík, K; Beran, P; Dolezal, J; Opekar, F

1978-07-01

169

Distribution of copper, nickel, and cadmium in the surface waters of the North Atlantic and North Pacific Ocean  

SciTech Connect

Concentrations of copper, nickel, and cadmium have been determined for about 250 surface water samples. Nonupwelling open-ocean concentrations of these metals are Cu, 0.5-1.4 nmol/kg: Ni, 1-2 nmol/kg; and Cd, less than 10 pmol/kg. In the equatorial Pacific upwelling zone, concentrations of Ni (3 nmol/kg) and Cd (80 pmol/kg) are higher than in the open ocean, but Cu (0.9 nmol/kg) is not significantly enriched. Metal concentrations are higher in cool, nutrient-rich eastern boundary currents: Cu, 1.5 nmol/kg: Ni, 3.5 nmol/kg and Cd, 30-50 pmol/kg. Copper is distinctly higher in the coastal waters of the Gulf of Panama (3--4 nmol/kg) and also higher in the shelf waters north of the Gulf Stream (2.5 nmol/kg): these copper enrichments may be caused by copper remobilized from mildly reducing shelf sediments and maintained by a coastal nutrient trap. In the open ocean, events of high-Cu water (1.5--3.5 nmol/kg) are seen on scales up to 60 km; presumably, these are due to the advection of coastal water into the ocean interior. The lowest copper concentrations in the North Pacific central gyre (0.5 nmol/kg: (Bruland, 1980) are lower than in the Sargasso Sea (1.3 nmol/kg), while for nickel the lowest concentrations are 2 nmol/kg in both the North Pacific and the North Atlantic. Nickel and cadmium, while generally correlated with the nutrients in surface waters, show distinct regional changes in their element-nutrient correlations. The residual concentrations of trace metals in the surface waters of the ocean can be explained if biological discrimination against trace metals relative to phosphorus increases as productivity decreases.

Boyle, E.A.; Huested, S.S.; Jones, S.P.

1981-09-20

170

The effects of feeding by the black bean aphidAphis fabae Scop. (Homoptera: Aphididae) on copper and cadmium accumulation in broad bean (Vicia faba L.).  

PubMed

Broad beans (Vicia faba L.), cultured hydroponically were supplied with 100 ?g mL(-1) copper or 50 ?g mL(-1) cadmium in nutrient solution. Samples of plant material from both nutrient regimes were analysed before and after infestation by the black bean aphid (Aphis fabae Scop.). Heavy aphid infestation resulted in a significant reduction in copper content of shoots in comparison with uninfested plants. A similar, but less well- defined, situation occurred in the case of cadmium.Further investigations examined the effects of different levels of aphid infestation on the above phenomena. In all cases the presence of feeding aphids reduced elemental accumulation in plant shoots. Long term infestation with population densities as low as three adult aphids showed a reduction in shoot copper and cadmium content. PMID:24202634

Crawford, L A; Hodkinson, I D; Lepp, N W

1990-09-01

171

Maternal and neonatal scalp hair concentrations of zinc, copper, cadmium, and lead: relationship to some lifestyle factors.  

PubMed

Postpartum scalp hair samples from 82 term-pregnancy mother/ neonate pairs were analyzed for their concentrations of zinc (Zn), copper (Cu), cadmium (Cd), and lead (Pb), using inductively coupled plasma-mass spectrometry. Maternal and neonatal Zn concentrations had geometric means (and 99% confidence intervals) of 122.5 microg/g (117.9--131.5 microg/g) and 146.9 microg (141.5--156.7 microg/g) respectively. Corresponding Cu values were 18.4 microg/g (17.6--23.8 microg/g) and 6.7 microg/g (6.3--7.6 microg/g). Those of Cd were 0.49 microg/g (0.47--0.69 microg/g) in the mothers and 0.57 microg/g (0.55--0.86 microg/g) in the neonates. For Pb, they were 7.95 microg/g (7.60--9.32 microg/g) and 4.56 microg/g (4.39--5.56 microg/g). Cigarette smoking, despite its relatively low prevalence (19.5%), was associated with lower Zn and higher Cd and Pb concentrations and in lower Zn/Cd and Zn/Pb molar concentration ratios. Smoking also altered interelemental relationships, particularly those of Zn with Cd and Pb and those between Cd and Pb. Smoking frequency appeared to show negative dose-response effects on maternal and neonatal Zn concentrations, Zn/Pb molar concentration ratios, and birth weight. Mothers with a history of oral contraceptive (OC) usage had significantly higher Cu concentrations and lower Zn/Cu molar concentration ratios than non users, with the highest Cu concentrations and lowest Zn/Cu values being associated with third-generation OCs. No similar effects were elicited in the respective neonatal Cu concentrations. Neither alcohol consumption nor prenatal supplementation with iron and/or folic acid had discernible effects on the maternal or neonatal elemental concentrations. The data from this study suggest that in a given population of term-pregnancy mothers and neonates, significant interindividual variations in hair trace element concentrations can occur, irrespective of commonality of general environment, and that lifestyle factors, including cigarette smoking and OC usage history, can be significant contributory factors to such variations. The data are discussed in relation to the effects of smoking-associated exposure to Cd and Pb exposure on Zn availability for placental transfer, as well as on the quantitative maternal Zn supply levels to the fetus resulting from the known tendency of smokers to have lower dietary intakes of Zn. PMID:16037607

Razagui, Ibrahim B-A; Ghribi, Ibrahim

2005-07-01

172

Morphology evolution of zinc-iron binary alloys electrodeposited with copper additive  

SciTech Connect

Zinc-iron electrodeposits have widely been adopted for surface treatment of automobile body steel sheet for corrosion resistance. Copper additive enhances dendrite formation of hexagonal columnar crystals of the zinc-iron electrodeposit. With 100 ppm of copper, these crystals show fine steps on (10 {center_dot} 0){eta} surfaces. With 150 ppm, the copper enhances nucleation on one of an apex on (00{center_dot}1){eta} of these crystals. With 300 ppm, the nucleation increases and fine platelet crystals precipitate preferentially at this apex. With further increase of copper to 1,000 ppm, the deposit becomes dendrite crystals and this apex becomes the growing tip of the dendrite.

Kondo, Kazuo; Murakami, Tomoya; Shinohara, Kunio [Univ. of Hokkaido, Sapporo (Japan)

1996-04-01

173

Chronic administration of iron and copper potentiates adipogenic effect of high fat diet in Wistar rats.  

PubMed

The primary objective of this research project is explore a possible adipogenic effect of iron and/or copper in albino Wistar rats kept on standard (STD) and high-fat (HFD) diets. The female Wistar rats in the study were divided into eight experimental groups (n = 6). Rats maintained on STD and HFD received 3 mg/l FeSO??7H?O, 4.88 mg/l CuSO? and a combination of 1.5 mg/l FeSO??7H?O and 2.44 mg/l CuSO? with drinking water. Control groups were kept on STD and HFD and received pure water without metal salts. Consumption of iron and copper in the groups of rats maintained on an STD did not produce a significant increase in weight, adipose tissue content or body mass index. However, the adipocyte size and infiltration were increased in the adipose tissue of STD-fed rats receiving a mixture of iron and copper with drinking water. The rats fed iron and copper and, especially, their combination on a HFD background had a significantly higher weight gain, adipose tissue content, morphometric parameters values and adipocyte size compared to STD- and HFD-fed controls. Iron and copper consumption produced their accumulation in the rats' adipose tissue. Moreover, the studied metals reduced adipose tissue concentration of chromium and vanadium. The lipoprotein profile and serum oxidative stress biomarkers were affected in the rats receiving the metals and STD. Hyperglycemia was observed in the rats receiving the studied metals on HFD-background. Based on the analysis of the test subjects, the study suggests that iron and copper administration, especially combined, may potentiate adipogenic effect of HFD. PMID:23657865

Tinkov, Alexey A; Polyakova, Valentina S; Nikonorov, Alexandr A

2013-06-01

174

Alteration of saliva and serum concentrations of manganese, copper, zinc, cadmium and lead among career welders  

PubMed Central

Human saliva offers a unique noninvasive approach for populational study. Purposes of this study were to investigate the feasibility of using saliva manganese (Mn) concentration as a biomarker of Mn exposure among career welders and to study the variations of Mn, copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb) in saliva as affected by the welding profession. Forty-nine male welders, of whom 28 were in the low exposed group and 21 in the high exposed group, were recruited. Control subjects were 33 military soldiers without metal exposure. Ambient Mn levels in breathing zones were 0.01, 0.24 and 2.21 mg/m3for control, low, and high exposed groups, respectively. Saliva samples were collected to quantify metals by inductive coupled plasma mass spectrometer (ICP-MS). Saliva concentrations of Mn and Cu were significantly higher in welders than in controls (p < 0.01); the variation in saliva levels appeared likely to be associated with airborne Mn levels among study populations. Saliva levels of Zn were significantly lower in welders than in controls (p < 0.05), while Cd and Pb levels in saliva were unchanged. Significant associations were observed between saliva and serum for Mn (r = 0.575, p < 0.05) and Cu (r = 0.50, p < 0.05). Moreover, saliva Mn concentrations were higher among welders with 5–10 years of employment than those with less than 5 years of employment. Linear regression analysis revealed a significant correlation between saliva Mn and Cu and between saliva Mn and Zn. Taken together, these data suggest that Mn concentrations in saliva appear reflective of welders’ exposure to airborne Mn and their years of welding experience. respectively. Elevated Mn levels among welders may alter the homeostasis of Cu and Zn.

Wang, Dixin; Du, Xuqin; Zheng, Wei

2014-01-01

175

Sorption of cadmium by an acid soil amended with compost and copper-mine tailing  

NASA Astrophysics Data System (ADS)

Humified materials from the compost industry and certain waste from mining operations can be used as low cost toxic metal adsorbents in soils having a very low sorption capacity. An experiment was designed to assess the sorption of cadmium (Cd) by an acid coarse-textured soil (pH 5.50) amended with peat moss-shrimp waste compost (PSC), and three copper-mine tailing samples rich in calcareous products, namely untreated tailing (MT), tailing + 10% of PSC (MTC-10) and tailing + 20% of PSC (MTC-20). The soil amendment rates ranged from 0 to 300 g/kg soil. The sorption measurement was carried out on 17 soils by adding 30 mL of 0.01 M CaCl2 solution containing 100 mg Cd/L, as CdCl2, to 1.00 g of soil. The suspension was shaken for 30 min and equilibrated at room temperature for 7 days. After centrifuging, the Cd concentration in the supernatant was measured by atomic absorption spectrophotometry. The sorption coefficient (Ks) was used to interpret the sorption data. Triplicate samples of the soils were used throughout the sorption study. MT (pH 7.7) amendment treatment was more effective than PSC (pH 6.8) treatment in raising the pH of acid sandy soil. Sorption increased with amendment additions depending on the type and rate of amendment application. The compost alone had the highest affinity for Cd, while the tailing alone exhibited the least affinity. The increasing order of Cd sorbed after amendment was: PSC > MTC-20 > MTC-10 > MT. The results indicate that PSC and Cu-mine tailing amended with PSC can be used as effective sorbents for anthropogenic Cd in acid sandy soils.

Karam, A.; Jaouich, A.

2009-04-01

176

Investigating the distribution of dissolved copper, zinc, silver and cadmium in the Pacific Ocean  

NASA Astrophysics Data System (ADS)

A stated goal of the GEOTRACES program is to better understand the large-scale distribution of trace metals in the marine environment. A characteristic feature of the soft Lewis acid metals like copper (Cu), zinc (Zn), silver (Ag) and cadmium (Cd) is their correlation with the major algal nutrients. These correlations imply that the proximate control on the distribution of these metals is microbial uptake at the ocean surface, sinking associated with particulate organic matter and subsequent remineralization in the ocean interior. Combined with sedimentary records of past metal concentrations such correlations can provide much needed information on water mass circulation and nutrient cycling in the paleo-ocean. Today, as trace nutrients and/or toxins these metals help shape microbial community composition and influence productivity. Here we present depth profiles through the low dissolved oxygen waters of the north Pacific which show decoupling of trace metal-macronutrient relationships driven by depletion anomalies of trace metal concentrations in the broad, low oxygen layer. Similar anomalies have been previously reported in permanently anoxic layers (e.g. fjords) or in waters in contact with suboxic sediments and attributed to sulfidic removal of soft trace metals. The observed trace metal behavior and trace metal-macronutrient relationships in the oxygen minimum layer in the northeastern Pacific is consistent with the possibility of sulfidic scavenging of soft metals and the formation of insoluble metal sulfides in the water column. Implications of this influence on the basin scale distribution of soft metals like Cu, Zn, Ag, Cd through scavenging in the spreading low oxygen layer in the northeastern Pacific are discussed.

Janssen, D. J.; Cullen, J. T.

2012-12-01

177

Reduction and aggregation of silver, copper and cadmium ions in aqueous solutions of gelatin and carboxymethyl cellulose  

NASA Astrophysics Data System (ADS)

Radiolytic reduction of silver, copper and cadmium ions and the subsequent formation of their clusters was studied in aqueous gelatin or carboxy methyl cellulose (CMC) solutions. Presence of gelatin or CMC in the solution affects the early processes. The rate of reduction by hydrated electron reduces due to complexation. However, when the ratio of silver ions to monomeric chains decreases over a certain limit the process of reduction inhibits completely. The effect of ionic strength or pH and the reducing radical on the rate of formation of colloidal Cu and Cd is also discussed.

Kapoor, S.; Gopinathan, C.

1998-08-01

178

State of adsorption layers of fatty acids on the surfaces of iron, manganese, and copper ferrites  

NASA Astrophysics Data System (ADS)

States of adsorbed substances in surface layers arising during the adsorption of oleic, linoleic, and linolenic acids from carbon tetrachloride, heptane, and cyclohexane solutions on the surfaces of iron, manganese, and copper ferrites, are investigated. Adsorption isotherms and two-dimensional state diagrams of surface layers of iron, manganese, and copper ferrites are obtained experimentally. It is shown that the adsorption of fatty acids from solutions in organic solvents proceeds via filling the volume of the ferrites' porous space with adsorption solutions, while the state of ferrite surface layers changes due to the structural rearrangement of adsorption solutions upon an increase in solute concentration.

Balmasova, O. V.; Ramazanova, A. G.; Korolev, V. V.

2012-07-01

179

[Evaluation of iron, zinc and copper contents in selected spices available on the Polish market].  

PubMed

The aim of the study was to evaluate the content of iron, zinc and copper in selected spices (pepper, parsley, dill, thyme, oregano, basil, marjoram, rosemary, juniper) from three companies. The contents of minerals were determined by flame AAS. Statistical analysis was carried out employing the STATISTICA software and using the ANOVA test. The high content of minerals was found in basil. Juniper contains relatively low quantities of these elements. It was shown a significant differences in iron, zinc and copper content in spices come from different companies. PMID:22171516

Suliburska, Joanna; Kaczmarek, Karolina

2011-01-01

180

Trace Element Status (Iron, Zinc, Copper, Chromium, Cobalt, and Nickel) in Iron-Deficiency Anaemia of Children under 3 Years  

PubMed Central

Aim. To determine trace element status and aetiologic factors for development of trace elements deficiencies in children with iron-deficiency anaemia (IDA) aged 0 to 3 years. Contingent and Methods. 30 patients of the University Hospital, Pleven, Bulgaria—I group; 48 patients of the Sumy Regional Child's Clinical Hospital, Sumy, Ukraine—II group; 25 healthy controls were investigated. Serum concentrations of iron, zinc, copper, chromium, cobalt, and nickel were determined spectrophotometrically and by atomic absorption spectrophotometry. Results. Because the obtained serum levels of zinc, copper, and chromium were near the lower reference limits, I group was divided into IA and IB. In IA group, serum concentrations were lower than the reference values for 47%, 57%, and 73% of patients, respectively. In IB group, these were within the reference values. In II group, results for zinc, cobalt, and nickel were significantly lower (P < 0.05), and results for copper were significantly higher in comparison to controls. Conclusion. Low serum concentrations of zinc, copper, cobalt, and nickel were mainly due to inadequate dietary intake, malabsorption, and micronutrient interactions in both studied groups. Increased serum copper in II group was probably due to metabolic changes resulting from adaptations in IDA. Data can be used for developing a diagnostic algorithm for IDA.

Angelova, Maria Georgieva; Petkova-Marinova, Tsvetelina Valentinova; Pogorielov, Maksym Vladimirovich; Loboda, Andrii Nikolaevich; Nedkova-Kolarova, Vania Nedkova; Bozhinova, Atanaska Naumova

2014-01-01

181

Trace Element Status (Iron, Zinc, Copper, Chromium, Cobalt, and Nickel) in Iron-Deficiency Anaemia of Children under 3 Years.  

PubMed

Aim. To determine trace element status and aetiologic factors for development of trace elements deficiencies in children with iron-deficiency anaemia (IDA) aged 0 to 3 years. Contingent and Methods. 30 patients of the University Hospital, Pleven, Bulgaria-I group; 48 patients of the Sumy Regional Child's Clinical Hospital, Sumy, Ukraine-II group; 25 healthy controls were investigated. Serum concentrations of iron, zinc, copper, chromium, cobalt, and nickel were determined spectrophotometrically and by atomic absorption spectrophotometry. Results. Because the obtained serum levels of zinc, copper, and chromium were near the lower reference limits, I group was divided into IA and IB. In IA group, serum concentrations were lower than the reference values for 47%, 57%, and 73% of patients, respectively. In IB group, these were within the reference values. In II group, results for zinc, cobalt, and nickel were significantly lower (P < 0.05), and results for copper were significantly higher in comparison to controls. Conclusion. Low serum concentrations of zinc, copper, cobalt, and nickel were mainly due to inadequate dietary intake, malabsorption, and micronutrient interactions in both studied groups. Increased serum copper in II group was probably due to metabolic changes resulting from adaptations in IDA. Data can be used for developing a diagnostic algorithm for IDA. PMID:24839556

Angelova, Maria Georgieva; Petkova-Marinova, Tsvetelina Valentinova; Pogorielov, Maksym Vladimirovich; Loboda, Andrii Nikolaevich; Nedkova-Kolarova, Vania Nedkova; Bozhinova, Atanaska Naumova

2014-01-01

182

Phormidium autumnale Growth and Anatoxin-a Production under Iron and Copper Stress  

PubMed Central

Studies on planktonic cyanobacteria have shown variability in cyanotoxin production, in response to changes in growth phase and environmental factors. Few studies have investigated cyanotoxin regulation in benthic mat-forming species, despite increasing reports on poisoning events caused by ingestion of these organisms. In this study, a method was developed to investigate changes in cyanotoxin quota in liquid cultures of benthic mat-forming cyanobacteria. Iron and copper are important in cellular processes and are well known to affect growth and selected metabolite production in cyanobacteria and algae. The effect of iron (40–4000 ?g L?1) and copper (2.5–250 ?g L?1) on growth and anatoxin-a quota in Phormidium autumnale was investigated in batch culture. These concentrations were chosen to span those found in freshwater, as well as those previously reported to be toxic to cyanobacteria. Anatoxin-a concentrations varied throughout the growth curve, with a maximum quota of between 0.49 and 0.55 pg cell?1 measured within the first two weeks of growth. Growth rates were significantly affected by copper and iron concentrations (P < 0.0001); however, no statistically significant difference between anatoxin-a quota maxima was observed. When the iron concentrations were 800 and 4000 ?g L?1, the P. autumnale cultures did not firmly attach to the substratum. At 250 ?g L?1 copper or either 40 or 4000 ?g L?1 iron, growth was suppressed.

Harland, Francine M. J.; Wood, Susanna A.; Moltchanova, Elena; Williamson, Wendy M.; Gaw, Sally

2013-01-01

183

The solubility of copper in lime-saturated and calcium ferrite-saturated liquid iron oxide  

Microsoft Academic Search

The solubility of copper in lime-saturated and calcium ferrite-saturated liquid iron oxide has been measured at 1300 ?C by\\u000a equilibrating copper-gold alloys with the melts in CO-CO2 atmospheres of oxygen potentials 10?7, 10?8, 10?9, and 10?10 atm. It was found that copper exhibits Henrian behavior in the oxide melts and that the solubility is given by\\u000a \\u000a \\u000a \\u000a \\u000a $$wt pct Cu =

J. Palacios; D. R. Gaskell

1993-01-01

184

Rates of dissolution of rotating iron cylinders in liquid copper and cu-fe alloys  

Microsoft Academic Search

Iron cylinders with molybdenum capped ends are rotated at speeds of 260, 570, and 835 rpm in liquid copper and Cu-Fe alloys\\u000a maintained at 1220?, 1300?C, and 1370?C under argon at 1 atm pressure. The dependence of the dissolution rate of the cylinders\\u000a on the concentration of iron in the bulk liquid is observed. The solution-rate constants defined by an

R. Ohno

1973-01-01

185

Kinetics of solution of hydrogen in liquid iron, nickel, and copper containing dissolved oxygen and sulfur  

Microsoft Academic Search

An investigation of the effect of surface active oxygen and sulfur on the rate of hydrogen solution in inductively stirred\\u000a liquid iron, nickel, and copper was made using a modified constant-volume Sieverts’ method. The overall and initial rates\\u000a of hydrogen solution in liquid iron and nickel were found to decrease with increasing oxygen content in concentration ranges\\u000a found in the

W. M. Small; R. H. Radzilowski; R. D. Pehlke

1973-01-01

186

Impact of Copper on an Alkali Promoted Iron Fischer–Tropsch Catalyst  

Microsoft Academic Search

Copper has traditionally been added to precipitated iron Fischer–Tropsch (FT) catalysts to facilitate reduction of Fe2O3 to zero valent iron during activation [M.E. Dry, in: J.R. Anderson and M. Boudart (eds), Catalysis Science and Technology, Vol. 1 (Springer-Verlag, New York, 1981) p. 179] by lowering the reduction temperature when activating with hydrogen, carbon monoxide or syngas [R.J. O'Brien et al.,

Robert J. O'Brien; Burtron H. Davis

2004-01-01

187

Effects of Copper and Austempering on Corrosion Behavior of Ductile Iron in 3.5 Pct Sodium Chloride  

NASA Astrophysics Data System (ADS)

Although alloying and heat treatments are common industrial practices to obtain ductile irons with desired mechanical properties, related information on how the two practices affect corrosion behavior is scarce. In this study, two ductile irons—with and without 1 wt pct copper addition—were austempered to obtain austempered ductile irons (ADIs). Polarization tests and salt spray tests were conducted to explore how both copper-alloying and austempering heat treatments influenced the corrosion behavior of ductile irons. The results showed that the corrosion resistance of 1 wt pct copper-alloyed ductile iron was better than that of the unalloyed one, while ADI had improved corrosion resistance compared with the as-cast. In particular, the ductile iron combined with the copper-alloying and austempering treatments increased the corrosion inhibition efficiency up to 84 pct as tested in 3.5 wt pct NaCl solution.

Hsu, Cheng-Hsun; Lin, Kuan-Ting

2013-10-01

188

Nuclear magnetic resonance of iron and copper disease states  

Microsoft Academic Search

The tissue levels of paramagnetic ions are an important factor in the determination of T⁠values as observed by nuclear magnetic resonance (NMR) imaging. The increased levels of iron present in human disease states such as hemochromatosis lead to decreased T⁠values. The mean liver T⁠of three patients with iron storage disease was determined to be 130 msec, significantly

V. M. Runge; J. A. Clanton; F. W. Smith; J. Hutchison; J. Mallard; C. L. Partain; A. E. Jr. James

1983-01-01

189

Decomposition of the sulfates of copper, iron (II), iron (III), nickel, and zinc: XPS, SEM, DRIFTS, XRD, and TGA study  

NASA Astrophysics Data System (ADS)

The bulk and surface characteristics during decomposition of the transition metal sulfates of copper, iron (II), iron (III), nickel, and zinc are investigated utilizing various spectroscopic techniques. An oxidized form of sulfur was detected on the surface during decomposition of all metal sulfate samples, except zinc sulfate. Surface characteristics were not necessarily representative of the bulk characteristics. Oxy-sulfate was observed with copper sulfate only. Lower decomposition temperatures were observed in vacuum as compared to those at atmospheric pressure. Uniform sulfur distribution was observed across sample cross sections. Analysis consisted of Scanning electron microscopy/X-ray microanalysis, X-ray photoelectron spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy, thermogravimetric analysis, and X-ray diffraction.

Siriwardane, Ranjani V.; Poston, James A., Jr.; Fisher, Edward P.; Shen, Ming-Shing; Miltz, Angela L.

1999-11-01

190

Bioabsorption of cadmium, copper and lead by the red macroalga Gelidium floridanum: Physiological responses and ultrastructure features.  

PubMed

Heavy metals, such as lead, copper, cadmium, zinc, and nickel, are among the most common pollutants found in both industrial and urban effluents. High concentrations of these metals cause severe toxic effects, especially to organisms living in the aquatic ecosystem. Cadmium (Cd), lead (Pb) and copper (Cu) are the heavy metals most frequently implicated as environmental contaminants, and they have been shown to affect development, growth, photosynthesis and respiration, and morphological cell organization in seaweeds. This paper aimed to evaluate the effects of 50?M and 100?M of Cd, Pb and Cu on growth rates, photosynthetic pigments, biochemical parameters and ultrastructure in Gelidium floridanum. To accomplish this, apical segments of G. floridanum were individually exposed to the respective heavy metals over a period of 7 days. Plants exposed to Cd, Cu and Pb showed discoloration of thallus pigmentation, chloroplast alteration, especially degeneration of thylakoids, and decrease in photosynthetic pigments, such as chlorophyll a and phycobiliproteins, in samples treated with Cd and Cu. Moreover, cell wall thickness and the volume of plastoglobuli increased. X-ray microanalysis detected Cd, Cu and Pb absorption in the cell wall. The results indicate that Cd, Pb and Cu negatively affect metabolic performance and cell ultrastructure in G. floridanum and that Cu was more toxic than either Pb or Cd. PMID:24793517

Dos Santos, Rodrigo W; Schmidt, Eder C; de L Felix, Marthiellen R; Polo, Luz K; Kreusch, Marianne; Pereira, Debora T; Costa, Giulia B; Simioni, Carmen; Chow, Fungyi; Ramlov, Fernanda; Maraschin, Marcelo; Bouzon, Zenilda L

2014-07-01

191

Cadmium, lead, calcium, magnesium, copper, and zinc concentrations in human infant tissues: their relationship to Sudden Infant Death Syndrome  

SciTech Connect

The purpose of this study was to determine whether there was any evidence of an excess of the toxic elements, cadmium and lead, or a deficiency of any of the essential elements, calcium, magnesium, copper, and zinc, in the tissues of infants who died of Sudden Infant Death Syndrome (SIDS) as compared to those of infants who died of other causes. The literature was reviewed for SIDS, mineral metabolism, and mineral interactions. Lung, liver, kidney, and rib specimens were obtained at autopsy from 130 infants who died suddenly and unexpectedly. There were 85 SIDS cases ranging in age from 2 to 64 weeks and 45, aged 1 to 92 weeks, who died of other causes. Concentrations of cadmium, lead, calcium, magnesium, copper, and zinc in each tissue were determined by electrothermal and flame atomic absorption spectrophotometry. Statistical analysis of the data showed that liver and rib lead concentrations and liver magnesium concentrations were significantly higher in SIDS tissues in the 4 to 26 week age group than in non-SIDS tissues in the same age group. There was no evidence of a deficiency of the essential minerals measured.

Erickson, M.M.

1981-01-01

192

Comparative Effects of Copper, Iron, Vanadium and Titanium on Low Density Lipoprotein Oxidation in vitro  

Microsoft Academic Search

Introduction: Oxidation of low density lipoprotein (LDL) has been strongly implicated in the phathogenesis of atherosclerosis. The use of oxidants in dietary food stuff may lead to the production of oxidized LDL and may increase both the development and the progression of atherosclerosis. The present work investigated the effects of some elements including: copper (Cu), iron (Fe), vanadium (V) and

Mohsen Ani; Ali Asghar Moshtaghie; Hassan Ahmadvand

2007-01-01

193

Determination of Iron, Nickel, Copper, and Cobalt in Tungsten and Tungsten Alloys.  

National Technical Information Service (NTIS)

Iron, nickel, copper, and cobalt in tungsten and tungsten alloys are analyzed spectrophotometrically by taking aliquots of a hydrofluoricnitric acid solution that has been buffered to a pH of 6 by the addition of ammonium tartrate and sodium borate. No su...

G. Norwitz H. Gordon

1964-01-01

194

Influences of Water Treatment Process on Iron and Copper Release in Distribution System  

Microsoft Academic Search

A pilot study was conducted to assess the effect of water quality changes on iron and copper release in distribution systems. Three finished waters were prepared from groundwater source by conventional treatment, lime softening and reverse osmosis (RO). To mimic desalinated seawater, sea salts were added to RO treated water. Both lime softening and RO treatment significantly decreased the calcium

Baoyou Shi; Weizhong Xiao; James S. Taylor

2006-01-01

195

Djerfisherite, alkali copper-iron sulfide: a new mineral from enstatite chondrites.  

PubMed

A new mineral, essentially a potassium-copper-iron sulfide, occurs in accessory amounts in the enstatite chondrites Kota Kota (a find) and St. Marks (a fall), and has been identified visually in the enstatite achondrite Pena Blanca Springs (a fall). The x-ray diffraction pattern, electron-microprobe analysis, and its appearance in polished sections all serve to identify it. PMID:17831500

Fuchs, L H

1966-07-01

196

Oxidative stress-mediated hepatotoxicity of iron and copper: Role of Kupffer cells  

Microsoft Academic Search

Iron- or copper-mediated catalysis leads to the generation of reactive oxygen species (ROS) that can attack biomolecules directly, with the consequent enhancement in membrane lipid peroxidation, DNA damage, and protein oxidation. Reactive nitrogen species (RNS) can also be formed, leading to nitration of aromatic structures in addition to the oxidative deterioration of cellular components. Kupffer cells, the resident macrophages of

Luis A. Videla; Virginia Fernández; Gladys Tapia; Patricia Varela

2003-01-01

197

Absorption of gaseous oxygen by liquid cobalt, copper, iron and nickel  

Microsoft Academic Search

An experimental investigation of the rates of oxygen solution in molten cobalt, copper, iron and nickel was carried out using pure oxygen and a constant-volume Sieverts' method. It was found that the volume of gaseous oxygen which initially reacted with the inductively stirred metals was strongly dependent on the physical nature of the oxide film which formed during the first

R. H. Radzilowski; R. D. Pehlke

1978-01-01

198

Fast method for the determination of copper, manganese and iron in seafood samples  

Microsoft Academic Search

A slurry sampling flame atomic absorption spectrometric method is proposed for the determination of copper, manganese and iron in oysters (Crassostrea rhizophora), clams (Anomalocardia brasiliana) and mussels (Mytella guiyanensis; Perna perna). Optimization was carried out using univariate methodology involving the following variables: nature and concentration of the acid solution for slurry preparation, sonication time and sample mass. The optimized conditions

Erik G. P. da Silva; Vanessa Hatje; Walter N. L. dos Santos; Letícia M. Costa; Ana R. A. Nogueira; Sérgio L. C. Ferreira

2008-01-01

199

Vitreous Analysis in Eyes Containing Copper and Iron Intraocular Foreign Bodies.  

National Technical Information Service (NTIS)

The analysis of vitreous to determine the presence and metallic type of an intraocular foreign body appears to be a rapid and reliable diagnostic technique with few limitations. In this study, copper and iron were selected for evaluation because these met...

T. E. Runyan E. A. Levri

1970-01-01

200

Zinc, copper, iron, and chromium concentrations in young patients with type 2 diabetes mellitus.  

PubMed

Homeostasis of trace elements can be disrupted by diabetes mellitus. On the other hand, disturbance in trace element status in diabetes mellitus may contribute to the insulin resistance and development of diabetic complications. The aim of present study was to compare the concentration of essential trace elements, zinc, copper, iron, and chromium in serum of patients who have type 2 diabetes mellitus (n = 20) with those of nondiabetic control subjects (n = 20). The serum concentrations of zinc, copper, iron, and chromium were measured by means of an atomic absorption spectrophotometer (Shimadzu AA 670, Kyoto, Japan) after acid digestion. The results of this study showed that the mean values of zinc, copper, and chromium were significantly lower in the serum of patients with diabetes as compared to the control subjects (P < 0.05). Our results show that deficiency of some essential trace elements may play a role in the development of diabetes mellitus. PMID:22351156

Basaki, M; Saeb, M; Nazifi, S; Shamsaei, H A

2012-08-01

201

Adsorption edge study about cadmium, copper, nickel and zinc adsorption by variable charge soils  

NASA Astrophysics Data System (ADS)

The improper discharge of industrial and urban residues and the inadvertent use of fertilizers and pesticides can result in soil and water pollution and improve the potential of trace metals to enter in the human food chain. Adsorption reactions occur at the solid/liquid interface and are the most important mechanisms for controlling the activity of metal ions in soil solution. In a complex system with amphoteric behavior, the comprehension of the mobility, availability and fate of pollutants in the soil system is crucial for the prediction of the environmental consequences and for development of prevention/remediation strategies. A comparative study of cadmium (Cd), copper (Cu), nickel (Ni) and zinc (Zn) adsorption by highly weathered soils was carried out. Surface (0-0.2m) and subsoil (B horizon) samples were taken from a Rhodic Kandiudalf (RH), an Anionic "Xanthic" Acrudox (XA) and an Anionic "Rhodic" Acrudox (RA), located in brazilian humid tropical area. As the pH and the ionic strength are important environmental factors influencing the solution chemistry of heavy metals in variable charge systems, adsorption envelopes, in a batch adsorption experiment, were elaborated by reacting, for 24 h, soil samples with individual 0.01, 0.1 and 1.0 mol L-1 Ca(NO3)2 aqueous solutions containing nitrate salts of the adsorptive heavy metal (Cd, Cu, Ni and Zn) at the initial concentration of 5 mg L-1, with an increasing pH value from 3.0 to 8.0. ?pH50-100%, the difference between the pH of 100 and 50 percent metal adsorption was determined. A sharp increase of adsorption density (adsorption edge) was observed within a very narrow pH range, usually less than two pH units. Commonly, the relative affinity of a soil for a metal cation increases with the tendency of the cation to form inner-sphere surface complexes. This may be caused by differences in extent of hydrolysis of Cu ions and in affinity of adsorption sites for Cu. In general, subsurface samples showed low ?pH50-100% when compared with surface ones, independently on metal ion type. ?pH50-100% indicated that Cu was preferentially adsorbed. pH50 values for Cd, Ni and Zn increased as the ionic strength increased, but not for Cu. This behavior indicated the weak electrostatic bonding mechanisms involved in the formation of outer-sphere complex between these metal ions and the soil adsorbents

Casagrande, J. C.; Mouta, E. R.; Soares, M. R.

2009-04-01

202

The effects of cadmium and copper on embryonic and larval development of ide Leuciscus idus L.  

PubMed

The effects of Cd and Cu on embryos and larvae of the ide Leuciscus idus were evaluated. The ide is an European cyprinid fish, natural populations of which tend to decrease. The ide is also used as a bioindicator organism to evaluate water quality. However, sensitivity of ide early developmental stages to heavy metal intoxication is not known. Fish were exposed to Cd or Cu (100 ?g/L) during embryonic, larval or both developmental periods. Survival of the embryos, time of hatching, size and quality of newly hatched larvae were evaluated at the end of embryonic period. Correctly developed larvae from the control and Cd or Cu-exposed groups were transferred to clean water, Cd or Cu solutions (100 ?g/L) immediately after hatching. Larval development was observed, and the larvae were photographed. Time of yolk sac resorption, onset of active feeding and swim bladder inflation were evaluated, and the measurements were done on body and swim bladder size. The results showed that exposure of embryos to Cd and Cu significantly reduced embryonic survival and increased frequency of body malformations and death in newly hatched larvae and delayed hatching. Exposure to Cd and Cu during larval period reduced larval survival, growth and delayed development (yolk utilization, beginning of active feeding and swim bladder inflation). Cadmium was more toxic to the ide embryos and larvae than copper. Exposures to metals during embryonic period alone caused adverse impact on larval performance even when larval development took place in clean water. However, exposure of embryos to Cu reduced toxic impact of metal on larvae in continuous Cu exposure compared to the non-preexposed fish, but no such an effect occurred in case of Cd exposure. The results show that even a short-term exposure to Cd or Cu during early development of ide may adversely affect recruitment of this species. Among the measured endpoints, quality of newly hatched larvae (frequency of body malformations and larvae dead immediately after hatching) and swim bladder size were the most sensitive to intoxication with both metals. Embryos were more sensitive to Cu intoxication than larvae, while in case of Cd, sensitivity of both stages was similar. PMID:23884542

Witeska, Malgorzata; Sarnowski, Piotr; ?ugowska, Katarzyna; Kowal, Ewelina

2014-02-01

203

Comparative transcriptomic characterization of aluminum, sodium chloride, cadmium and copper rhizotoxicities in Arabidopsis thaliana  

PubMed Central

Background Rhizotoxic ions in problem soils inhibit nutrient and water acquisition by roots, which in turn leads to reduced crop yields. Previous studies on the effects of rhizotoxic ions on root growth and physiological functions suggested that some mechanisms were common to all rhizotoxins, while others were more specific. To understand this complex system, we performed comparative transcriptomic analysis with various rhizotoxic ions, followed by bioinformatics analysis, in the model plant Arabidopsis thaliana. Results Roots of Arabidopsis were treated with the major rhizotoxic stressors, aluminum (Al) ions, cadmium (Cd) ions, copper (Cu) ions and sodium (NaCl) chloride, and the gene expression responses were analyzed by DNA array technology. The top 2.5% of genes whose expression was most increased by each stressor were compared with identify common and specific gene expression responses induced by these stressors. A number of genes encoding glutathione-S-transferases, peroxidases, Ca-binding proteins and a trehalose-synthesizing enzyme were induced by all stressors. In contrast, gene ontological categorization identified sets of genes uniquely induced by each stressor, with distinct patterns of biological processes and molecular function. These contained known resistance genes for each stressor, such as AtALMT1 (encoding Al-activated malate transporter) in the Al-specific group and DREB (encoding dehydration responsive element binding protein) in the NaCl-specific group. These gene groups are likely to reflect the common and differential cellular responses and the induction of defense systems in response to each ion. We also identified co-expressed gene groups specific to rhizotoxic ions, which might aid further detailed investigation of the response mechanisms. Conclusion In order to understand the complex responses of roots to rhizotoxic ions, we performed comparative transcriptomic analysis followed by bioinformatics characterization. Our analyses revealed that both general and specific genes were induced in Arabidopsis roots exposed to various rhizotoxic ions. Several defense systems, such as the production of reactive oxygen species and disturbance of Ca homeostasis, were triggered by all stressors, while specific defense genes were also induced by individual stressors. Similar studies in different plant species could help to clarify the resistance mechanisms at the molecular level to provide information that can be utilized for marker-assisted selection.

Zhao, Cheng-Ri; Ikka, Takashi; Sawaki, Yoshiharu; Kobayashi, Yuriko; Suzuki, Yuji; Hibino, Takashi; Sato, Shigeru; Sakurai, Nozomu; Shibata, Daisuke; Koyama, Hiroyuki

2009-01-01

204

MD description of damage production in displacement cascades in copper and ?-iron  

NASA Astrophysics Data System (ADS)

Molecular dynamics computer simulation was applied for an extensive study of primary damage creation in displacement cascades in copper and ?-iron. Primary knock-on atom energy, Ep, of up to 25 keV in copper and 100 keV in iron was considered for irradiation temperatures in the range 100-900 K. Special attention was paid to comprehensive statistical treatment of the number and type of defects created in cascades by conducting multiple simulations for each value of energy and temperature. The total number of point defects per cascade is significantly lower than that predicted by the NRT model and rather similar in the two metals. The fraction of self-interstitial atoms (SIAs) and vacancies that agglomerate in clusters in the cascade process was analysed in detail. The clustered fraction of SIAs increases with temperature increase and is larger in copper than iron. SIA clusters have a variety of forms in both metals and, although most are glissile clusters of parallel crowdions, a significant fraction are sessile. The latter include Frank dislocation loops in copper. Tightly packed arrangements of vacancies do not form in iron, and so the fraction of clustered vacancies depends strongly on the range within which point defects are defined to be near-neighbours. Arrangements of vacancies in first-neighbour sites are common in copper. Most are irregular stacking fault tetrahedra (SFTs). In 53 simulations of cascades with Ep=25 keV at 100 K, the largest cluster formed contained 89 vacancies. The size spectrum of SFT-like clusters is similar to that found experimentally in neutron-irradiated copper, suggesting that the SFTs observed in experiment are formed directly in the cascade process.

Bacon, D. J.; Osetsky, Yu. N.; Stoller, R.; Voskoboinikov, R. E.

2003-12-01

205

MD description of damage production in displacement cascades in copper and ?-iron.  

SciTech Connect

Molecular dynamics computer simulation was applied for an extensive study of primary damage creation in displacement cascades in copper and {alpha}-iron. Primary knock-on atom energy, E{sub p}, of up to 25 keV in copper and 100 keV in iron was considered for irradiation temperatures in the range 100-900 K. Special attention was paid to comprehensive statistical treatment of the number and type of defects created in cascades by conducting multiple simulations for each value of energy and temperature. The total number of point defects per cascade is significantly lower than that predicted by the NRT model and rather similar in the two metals. The fraction of self-interstitial atoms (SIAs) and vacancies that agglomerate in clusters in the cascade process was analysed in detail. The clustered fraction of SIAs increases with temperature increase and is larger in copper than iron. SIA clusters have a variety of forms in both metals and, although most are glissile clusters of parallel crowdions, a significant fraction are sessile. The latter include Frank dislocation loops in copper. Tightly packed arrangements of vacancies do not form in iron, and so the fraction of clustered vacancies depends strongly on the range within which point defects are defined to be near-neighbours. Arrangements of vacancies in first-neighbour sites are common in copper. Most are irregular stacking fault tetrahedra (SFTs). In 53 simulations of cascades with E{sub p} = 25 keV at 100 K, the largest cluster formed contained 89 vacancies. The size spectrum of SFT-like clusters is similar to that found experimentally in neutron-irradiated copper, suggesting that the SFTs observed in experiment are formed directly in the cascade process.

Bacon, David J [University of Liverpool; Osetskiy, Yury N [ORNL; Stoller, Roger E [ORNL; Voskoboinikov, Roman E [University of Liverpool

2003-01-01

206

Combined Toxicity of Dissolved Mercury With Copper, Lead and Cadmium on Embryogenesis and Early Larval Growth of the Paracentrotus Lividus Sea-Urchin  

Microsoft Academic Search

The individual and combined toxicity of dissolved mercury, copper, lead and cadmium has been investigated by using the Paracentrotus lividus sea-urchin embryo-larval bioassay. Embryogenesis success and early larval growth have been recorded after incubation of fertilised eggs in seawater, both with single metals and binary combinations of Hg with every other metal. For individual metals the ranking of toxicity was

N. Fernández; R. Beiras

2001-01-01

207

Biotransference and biomagnification of selenium copper, cadmium, zinc, arsenic and lead in a temperate seagrass ecosystem from Lake Macquarie Estuary, NSW, Australia  

Microsoft Academic Search

In this study the biotransference of selenium copper, cadmium, zinc, arsenic and lead was measured in a contaminated seagrass ecosystem in Lake Macquarie, NSW, Australia, to determine if biomagnification of these trace metals is occurring and if they reach concentrations that pose a threat to the resident organisms or human consumers. Selenium was found to biomagnify, exceeding maximum permitted concentrations

M Barwick; W Maher

2003-01-01

208

Simultaneous Determination of Cadmium, Copper, Lead and Zinc in Amino Acid Parenteral Nutrition Solutions by Anodic Stripping Voltammetry and Sample Digestion by UV Irradiation  

Microsoft Academic Search

Irradiation with ultraviolet (UV) energy was investigated to assay cadmium, copper, lead, and zinc by anodic stripping voltammetry (ASV) in amino acid parenteral nutrition (PN) solutions. Sample digestion by UV irradiation showed the best performances to liberate the metals from the samples (metal recoveries between 90% and 102%) in comparison with classical oxidative wet digestion methods. The best UV digestion

Paulo C. do Nascimento; Marieli da S. Marques; Maurício Hilgemann; Leandro M. de Carvalho; Denise Bohrer; Solange G. Pomblum; Sabrina Schirmer

2006-01-01

209

Flow injection sorbent extraction with dialkyldithiophosphates as chelating agent for the determination of cadmium, copper and lead by flame atomic absorption spectrometry  

NASA Astrophysics Data System (ADS)

Using octadecyl functional groups (C 18) bonded to silica gel as sorbent and methanol as eluent, the flow injection sorbent extraction features of dialkyldithiophosphates (RO) 2P(S)S - as the chelating agent for cadmium, copper and lead was investigated in respect of the effects of pH, alkyl substituent group, reagent concentration and masking agent, with flame atomic absorption spectrometric detection. The elements are quantitatively extracted with the short-alkyl-chain reagents (R up to propyl) in acidic medium. The extractability decreases with the number of carbon atoms in the alkyl groups of the reagents and with the reagent concentration when the alkyl groups are larger than butyl, but masking agents increase the extractability. An explanation proposed for this effect is the formation of polynuclear chelates. Diethyldithiophosphate can be used for the selective determination of cadmium, copper and lead in digested solid environmental samples. With 20 s sample loading at 8.7 ml min -1, the enhancement factors are 35 for cadmium and copper or 26 for lead; the detection limits (3?) are 0.8, 1.4 and 10.0 ?g 1 -1 for cadmium, copper and lead, respectively.

Ma, Renli; Adams, Freddy

1996-12-01

210

Seasonal Variation in Copper, Zinc, Chromium, Lead and Cadmium Levels in Hepatopancreas, Gill and Muscle Tissues of the Mussel Brachidontes pharaonis Fischer, Collected along the Mersin Coast, Turkey  

Microsoft Academic Search

Levels of copper, zinc, cadmium, chromium and lead were determined in the gill, hepatopancreas and muscle tissues of Brachidontes pharaonis collected from the Mersin coasts of Turkey. Water and animal samples were collected monthly from the four stations between\\u000a June 2002 and May 2003 for metal determinations. Metal levels in water samples of Mersin coasts were higher than those measured

Fahri Karayakar; Cahit Erdem; Bedii C?c?k

2007-01-01

211

The common mussel Mytilus edulis as an indicator of pollution by zinc, cadmium, lead and copper. I. Effects of environmental variables on uptake of metals  

Microsoft Academic Search

The net uptake of zinc, cadmium, lead and copper by the common mussel Mytilus edulis (L.) exposed to different conditions was investigated with a view to using this species as an indicator of contamination of the marine environment by these metals. The variables studied were season, position of the mussel in the water column, water salinity, water temperature, and the

D. J. H. Phillips

1976-01-01

212

Iron-copper metallization for flexible solar/cell arrays  

NASA Astrophysics Data System (ADS)

The feasibility of a copper-base metallization for shallow-junction cells applied in flexible solar arrays in space is discussed. This type of metallization will reduce usage of precious metals (such as silver), increase case of bonding (by welding or by soldering) and eliminate heavy high Z interconnects (such as molybdenum). The main points of concern are stability against thermally induced diffusion of copper into silicon which causes degradation of shallow cell junctions, and low series resistance of the contact with semiconductor which promotes cell efficiency.

Lavendel, H. W.

1983-11-01

213

Characterizing the role of rice NRAMP5 in Manganese, Iron and Cadmium Transport  

PubMed Central

Metals like manganese (Mn) and iron (Fe) are essential for metabolism, while cadmium (Cd) is toxic for virtually all living organisms. Understanding the transport of these metals is important for breeding better crops. We have identified that OsNRAMP5 contributes to Mn, Fe and Cd transport in rice. OsNRAMP5 expression was restricted to roots epidermis, exodermis, and outer layers of the cortex as well as in tissues around the xylem. OsNRAMP5 localized to the plasma membrane, and complemented the growth of yeast strains defective in Mn, Fe, and Cd transport. OsNRAMP5 RNAi (OsNRAMP5i) plants accumulated less Mn in the roots, and less Mn and Fe in shoots, and xylem sap. The suppression of OsNRAMP5 promoted Cd translocation to shoots, highlighting the importance of this gene for Cd phytoremediation. These data reveal that OsNRAMP5 contributes to Mn, Cd, and Fe transport in rice and is important for plant growth and development.

Ishimaru, Yasuhiro; Takahashi, Ryuichi; Bashir, Khurram; Shimo, Hugo; Senoura, Takeshi; Sugimoto, Kazuhiko; Ono, Kazuko; Yano, Masahiro; Ishikawa, Satoru; Arao, Tomohito; Nakanishi, Hiromi; Nishizawa, Naoko K.

2012-01-01

214

Oxidation resistant copper  

SciTech Connect

Oxidation resistant particles composed of copper and at least one metal having a valence of +2 or +3 and having an intermediate lattice energy for the metal in its hydroxide form. The metal is selected from nickel, cobalt, iron, manganese, cadmium, zinc, tin, magnesium, calcium and chromium. In one embodiment, the phases of copper and at least one metal in the particles are separate and the concentration of the metal is greater near the surface of the particles than inwardly thereof. Process for making the oxidation resistant copper particles includes the steps of dissolving a copper salt and a salt of at least one of the metals in a suitable solvent or diluent; forming primary particles of copper and at least one metal in basic form by mixing a base and the salt solution; separating, washing and drying the primary particles; reducing the primary particles to metallic form; and heat treating the particles in metallic form at an elevated temperature.

Edelstein, A.S.; Kaatz, F.H.; Harris, V.G.

1993-11-15

215

Zinc pyrithione inhibits yeast growth through copper influx and inactivation of iron-sulfur proteins.  

PubMed

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

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

2011-12-01

216

Magnetic effects of hydrothermal alteration in porphyry copper and iron-oxide copper-gold systems: A review  

NASA Astrophysics Data System (ADS)

Magnetic anomaly patterns can be used as a tool for mapping lithology, metamorphic zones and hydrothermal alteration systems, as well as identifying structures that may control passage of magmas or hydrothermal fluids associated with mineralisation. Reliable geological interpretation of mineralised systems requires an understanding of the magmatic, metamorphic and hydrothermal processes that create, alter and destroy magnetic minerals in rocks. Predictive magnetic exploration models for porphyry copper and iron oxide copper-gold (IOCG) deposits can be derived from standard geological models by integrating magnetic petrological principles with petrophysical data, deposit descriptions, and modelling of observed magnetic signatures of these deposits. Even within a particular geological province, the magnetic signatures of similar deposits may differ substantially, due to differences in the local geological setting. Searching for “look-alike” signatures of a known deposit is likely to be unrewarding unless pertinent geological factors are taken into account. These factors include the tectonic setting and magma type, composition and disposition of host rocks, depth of emplacement and post-emplacement erosion level, depth of burial beneath younger cover, post-emplacement faulting and tilting, remanence effects contingent on ages of intrusion and alteration, and metamorphism. Because the effects of these factors on magnetic signatures are reasonably well understood, theoretical magnetic signatures appropriate for the local geological environment can qualitatively guide exploration and make semiquantitative predictions of anomaly amplitudes and patterns. The predictive models also allow detectability of deposit signatures to be assessed, for example when deposits are buried beneath a considerable thickness of nonmagnetic overburden, are covered by highly magnetic heterogeneous volcanic rocks, or there is a strong regional magnetic gradient. This paper reviews the effects of hydrothermal alteration on magnetic properties and magnetic signatures of porphyry copper and iron oxide copper-gold systems and presents examples of predictive magnetic exploration models, and their predicted signatures, in various geological circumstances.

Clark, David A.

2014-06-01

217

The ColRS signal transduction system responds to the excess of external zinc, iron, manganese, and cadmium  

PubMed Central

Background The ColRS two-component system has been shown to contribute to the membrane functionality and stress tolerance of Pseudomonas putida as well as to the virulence of Pseudomonas aeruginosa and plant pathogenic Xanthomonas species. However, the conditions activating the ColRS pathway and the signal(s) sensed by ColS have remained unknown. Here we aimed to analyze the role of the ColRS system in metal tolerance of P. putida and to test whether ColS can respond to metal excess. Results We show that the ColRS system is necessary for P. putida to tolerate the excess of iron and zinc, and that it also contributes to manganese and cadmium tolerance. Excess of iron, zinc, manganese or cadmium activates ColRS signaling and as a result modifies the expression of ColR-regulated genes. Our data suggest that the genes in the ColR regulon are functionally redundant, as several loci have to be deleted to observe a significant decrease in metal tolerance. Site-directed mutagenesis of ColS revealed that excess of iron and, surprisingly, also zinc are sensed by a conserved ExxE motif in ColS’s periplasmic domain. While ColS is able to sense different metals, it still discriminates between the two oxidation states of iron, specifically responding to ferric and not ferrous iron. We propose a signal perception model involving a dimeric ColS, where each monomer donates one ExxE motif for metal binding. Conclusions Several transition metals are essential for living organisms in certain amounts, but toxic in excess. We show that ColRS is a sensor system which detects and responds to the excess of physiologically important metals such as zinc, iron and manganese. Thus, the ColRS system is an important factor for metal homeostasis and tolerance in P. putida.

2014-01-01

218

Fabrication of a nanocomposite from in situ iron nanoparticle reinforced copper alloy.  

PubMed

In situ iron nanoparticle reinforced Cu-3Sn-8Zn-6Pb alloy has been fabricated by centrifugal casting in a vacuum chamber with a medium frequency electrical furnace. The microstructure of this alloy was analyzed with a scanning electron microscope (SEM) and a high-resolution transmission electron microscope (HRTEM), and the results show that the grains of Cu-3Sn-8Zn-6Pb alloy without iron have a typical dendrite structure with dimensions from 500 to 1500 microm, and the grains of the alloy with the addition of 1% iron are small and equiaxed, with dimensions from 20 to 60 microm. Then, the relatively uniform dispersed particles in the copper matrix were identified with the HRTEM to be pure iron with dimensions in the order of 2-20 nm. The mechanical properties of the alloys were measured and the results show a significant increase in the tensile strength of the alloy with iron nanoparticles and a slight increase of the elongation compared to that without iron. The mechanism of formation of the iron nanoparticles was analyzed by thermodynamic and dynamic theories, and the results indicate that the in situ iron nanoparticles of Cu-3Sn-8Zn-6Pb alloy can reasonably form during solidification in the centrifugal casting technique. PMID:19417426

Wang, Zidong; Wang, Xuewen; Wang, Qiangsong; Shih, I; Xu, J J

2009-02-18

219

Summary of ENDF/B-V evaluations for carbon, calcium, iron, copper, and lead and ENDF/B-V Revision 2 for calcium and iron  

SciTech Connect

This report, together with documents already published, describes the ENDF/B-V evaluations of the neutron and gamma-ray-production cross sections for carbon, calcium, iron, copper, and lead and the ENDF/B-V Revision 2 evaluations for calcium and iron.

Fu, C Y

1982-09-01

220

Determination of arsenic, antimony, bismuth, cadmium, copper, lead, molybdenum, silver and zinc in geological materials by atomic-absorption spectrometry  

USGS Publications Warehouse

Arsenic, antimony, bismuth, cadmium, copper, lead, molybdenum, silver and zinc are very useful elements in geochemical exploration. In the proposed method, geological samples are fused with potassium pyrosulphate and the fusate is dissolved in a solution of hydrochloric acid, ascorbic acid and potassium iodide. When this solution is shaken with a 10% V/V Aliquat 336 - isobutyl methyl ketone organic phase, the nine elements of interest are selectively partitioned in the organic phase. All nine elements can then be determined in the organic phase using flame atomic-absorption spectrometry. The method is rapid and allows the determination of Ag and Cd at levels down to 0.1 p.p.m., Cu, Mo, and Zn down to 0.5 p.p.m., Pb, Bi and Sb down to 1 p.p.m. and As down to 5 p.p.m. in geological materials.

Viets, J. G.; O'Leary, R. M.; Robert, Clark, J.

1984-01-01

221

A test battery approach to the ecotoxicological evaluation of cadmium and copper employing a battery of marine bioassays.  

PubMed

Heavy metals are ubiquitous contaminants of the marine environment and can accumulate and persist in sediments. The toxicity of metal contaminants in sediments to organisms is dependent on the bioavailability of the metals in both the water and sediment phases and the sensitivity of the organism to the metal exposure. This study investigated the effects of two metal contaminants of concern (CdCl(2) and CuCl(2)) on a battery of marine bioassays employed for sediment assessment. Cadmium, a known carcinogen and widespread marine pollutant, was found to be the least toxic of the two assayed metals in all in vivo tests. However, CdCl(2) was found to be more toxic to the fish cell lines PLHC-1 and RTG-2 than CuCl(2). Tisbe battagliai was the most sensitive species to both metals and the Microtox and cell lines were the least sensitive (cadmium was found to be three orders of magnitude less toxic to Vibrio fischeri than to T. battagliai). The sensitivity of Tetraselmis suecica to the two metals varied greatly. Marine microalgae are among the organisms that can tolerate higher levels of cadmium. This hypothesis is demonstrated in this study where it was not possible to derive an EC(50) value for CdCl(2) and the marine prasinophyte, T. suecica. Conversely, CuCl(2) was observed to be highly toxic to the marine alga, EC(50) of 1.19 mg l(-1). The genotoxic effect of Cu on the marine phytoplankton was evaluated using the Comet assay. Copper concentrations ranging from 0.25 to 2.50 mg l(-1) were used to evaluate the effects. DNA damage was measured as percent number of comets and normal cells. There was no significant DNA damage observed at any concentration of CuCl(2) tested and no correlation with growth inhibition and genetic damage was found. PMID:19283472

Macken, Ailbhe; Giltrap, Michelle; Ryall, Kim; Foley, Barry; McGovern, Evin; McHugh, Brendan; Davoren, Maria

2009-05-01

222

Blood concentration of copper, cadmium, zinc and lead in horses and its relation to hematological and biochemical parameters.  

PubMed

Environmental pollution results in serious health hazards to animals and blood analysis serves as a good alternative for health status assessment. The target of this study was to analyze the concentration of selected metals in equine blood, to analyze the blood parameters and to find possible correlations. Blood samples were collected from the vena jugularis of healthy adult horses. The highest concentration of all elements was found in whole blood (Cu 3.84 ± 0.90 mg L(-1); Cd = 0.81 ± 0.90 mg L(-1); Zn 26.67 ± 14.12 mg L(-1); Pb 9.33 ± 5.76 mg L(-1)). Higher concentrations of copper, cadmium, zinc and lead were detected in blood clots compared to blood sera (44.04%). A similar tendency was found for cadmium (50%), zinc (13.08%) and lead (46.02%), which showed generally higher concentrations in blood clots (cells). Correlation analysis proved some relations between analyzed elements. In blood clots there is a strong positive correlation between Cd - Pb (r = 0.93) and Zn - Pb (r = 0.71) was detected. For biochemical and hematological parameters mainly medium correlations were detected. Obtained results prove different correlations of analyzed elements in blood components as well as the effect on parameters of blood biochemical and hematological profiles. PMID:24766599

Massanyi, Peter; Stawarz, Robert; Halo, Marko; Formicki, Grzegorz; Lukac, Norbert; Cupka, Peter; Schwarcz, Pavol; Kovacik, Anton; Tusimova, Eva; Kovacik, Jaroslav

2014-07-01

223

Direct Functionalization of (Un)protected Tetrahydroisoquinoline and Isochroman under Iron and Copper Catalysis: Two Metals, Two Mechanisms  

PubMed Central

A highly facile, straightforward synthesis of 1-(3-indolyl)-tetrahydroisoquinolines was developed using either simple copper or iron catalysts. N-protected and unprotected tetrahydroisoquinolines (THIQ) could be used as starting materials. Extension of the substrate scope of the pronucleophile from indoles to pyrroles and electron-rich arenes was realized. Additionally, methoxyphenylation is not limited to THIQ but can be carried out on isochroman as well, again employing iron and copper catalysis.

2011-01-01

224

The influence of selected antihypertensive drugs on zinc, copper, and iron status in spontaneously hypertensive rats.  

PubMed

Mineral homeostasis in hypertensive patients may be affected by hypotensive drugs. The aim of this study was to assess the influence of selected antihypertensive drugs on mineral homeostasis in a rat model of hypertension. Eight-week-old male spontaneously hypertensive rats (SHRs) were treated with perindopril, metoprolol, indapamide, amlodipine, or no drug for 45 days. In another experiment, the SHRs were treated with indapamide or amlodipine in the presence of zinc and copper gluconate supplement. Lipids, glucose, and insulin levels along with superoxide dismutase and catalase activities were assayed in serum. Iron, zinc, and copper concentrations in serum, erythrocytes, and tissues were determined using the flame atomic absorption spectrometry. Blood pressure was measured using a tail-cuff plethysmograph. Treatment with indapamide and amlodipine was found to significantly lower zinc levels in serum, erythrocytes, livers, and spleens of the SHRs, as well as copper levels in the kidneys, compared with the control no-drug group. A markedly higher concentration of glucose was found in the indapamide-treated rats. Supplementing the indapamide-treated SHRs with zinc and copper gluconate resulted in a significant decrease in both systolic and diastolic blood pressure, and also lowered serum glucose and triglyceride concentrations and HOMA (homeostasis model assessment-insulin resistance) values. The results show that indapamide and amlodipine disturb zinc and copper homeostasis in SHRs. Supplementation with zinc and copper restores mineral homeostasis in SHRs treated with indapamide and amlodipine, and also corrects metabolic imbalances while improving the antihypertensive efficiency of indapamide. PMID:24927993

Suliburska, Joanna; Bogdanski, Pawe?; Jakubowski, Hieronim

2014-09-01

225

DETERMINATION OF ZINC, CADMIUM, LEAD, AND COPPER IN WATER BY ANODIC STRIPPING VOLTAMMETRY  

EPA Science Inventory

The Tennessee Valley Authority developed a method of differential pulse anodic stripping voltammetry for determining total concentrations of cadmium and lead in water samples from ash ponds at steam-electric generating plants. After digestion of the sample and addition of reagent...

226

Phytochelatins as biomarkers for heavy metal toxicity in maize: Single metal effects of copper and cadmium  

Microsoft Academic Search

Contamination of soils with heavy metals becomes more and more a problem in many countries all over the world. In areas where metal contaminated soils are used for food crop production, metals relatively mobile within the plant, such as cadmium (Cd) and zinc (Zn) can easily come into the food chain with great risks for human health. Since bioavailability of

W. G. Keltjens; M. L. van Beusichem

1998-01-01

227

[Secondary osteoporosis or secondary contributors to bone loss in fracture. Bone metabolism and heavy metals (cadmium and iron) ].  

PubMed

Fibroblast growth factor 23 (FGF23) is a bone-derived phosphaturic factor and is known to regulate blood inorganic phosphate (Pi) . Cadmium (Cd) , a toxic transition metal, which is widely used in industry, affecting human health and through occupational and environmental exposure. Phosphaturia has been documented following Cd exposure in both human and experimental animals. In animal study, Cd administration increases serum FGF23 concentrations. Moreover, medication such as infusion of select iron-containing compounds increases serum FGF23 concentrations, with patients developing hypophosphatemia. Thus, a relationship between metal ion (Cd and Fe) and FGF23 metabolic pathway has been proposed. PMID:23999366

Kido, Shinsuke

2013-09-01

228

Generation of oxidant response to copper and iron nanoparticles and salts: Stimulation by ascorbate  

PubMed Central

The present work describes a two-stage approach to analyzing combustion-generated samples for their potential to produce oxidant stress. This approach is illustrated with the two commonly encountered transition metals, copper and iron. First, their abilities to generate hydroxyl radical were measured in a cell-free, phosphate-buffered saline solution containing ascorbate and/or citrate. Second, their abilities to induce heme oxygenase-1 in cultured human epidermal keratinocytes were assessed in cell culture. Combustion-generated copper oxide nanoparticles were active in both assays and were found to be soluble in culture medium. Depletion of glutathione in the cells or loading the cells with ascorbate greatly increased heme oxygenase-1 induction in the presence of copper. By contrast, iron oxide nanoparticles were active in the phosphate buffered saline but not in cell culture, and they aggregated in culture medium. Soluble salts of copper and iron exhibited the same contrast in activities as the respective combustion-generated particles. The results suggest that the capability of combustion-generated environmental samples to produce oxidant stress can be screened effectively in a two step process, first in phosphate buffered saline with ascorbate and subsequently in epithelial cell culture for those exhibiting activity initially. The results also point to an unanticipated interaction in cells of oxidant stress-generating metals with an anti-oxidant (ascorbate) that is usually missing in culture medium formulations. Thus, ascorbate supplementation of cultured human cells is likely to improve their ability to model the in vivo effects of particulate matter containing copper and other redox-active metals.

Rice, Robert H.; Vidrio, Edgar A.; Kumfer, Benjamin M.; Qin, Qin; Willits, Neil H.; Kennedy, Ian M.; Anastasio, Cort

2009-01-01

229

Effect of sulfite exposure on zinc, iron, and copper levels in rat liver and kidney tissues  

Microsoft Academic Search

Sulfite is a potentially toxic molecule that might enter the body via ingestion, inhalation, or injection. For cellular detoxification,\\u000a mammalians rely on sulfite oxidase to convert sulfite to sulfate. The purpose of this research was to determine the effect\\u000a of sulfite on zinc, iron, and copper levels in rat liver and kidney tissues. Forty normal and sulfite oxidase-deficient male\\u000a albino

Vural Kucukatay; Sebahat Turgut; Erdogan Kocamaz; Gulten Emmungil; Melek Bor-Kucukatay; Gunfer Turgut; Hakan Akca; Huseyin Bagci

2006-01-01

230

Effect of Copper on the Decomposition of Ethylene over an Iron Catalyst  

Microsoft Academic Search

The catalytic properties of a series of unsupported copper–iron powders of varying composition were investigated by using a probe reaction of ethylene and hydrogen at temperatures over the range 450 to 800°C. Analysis of both the gas-phase products and the solid carbon, mainly in the form of filamentous structures, produced during the reaction provided anin situmethod for monitoring the changes

N. Krishnankutty; N. M. Rodriguez; R. T. K. Baker

1996-01-01

231

Copper, Chromium, Manganese, Iron, Nickel, and Zinc Levels in Biological Samples of Diabetes Mellitus Patients  

Microsoft Academic Search

There is accumulating evidence that the metabolism of several trace elements is altered in diabetes mellitus and that these\\u000a nutrients might have specific roles in the pathogenesis and progress of this disease. The aim of present study was to compare\\u000a the level of essential trace elements, chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn) in

Tasneem Gul Kazi; Hassan Imran Afridi; Naveed Kazi; Mohammad Khan Jamali; Mohammad Bilal Arain; Nussarat Jalbani; Ghulam Abbas Kandhro

2008-01-01

232

Regional distribution of manganese, iron, copper, and zinc in the rat brain during development  

Microsoft Academic Search

Manganese (Mn), iron (Fe), copper (Cu), and zinc (Zn) concentrations were determined in the brain regions of normal 1-, 3-, 5-, 7-, 14-, 21-, 42-, 77-, and 147-day-old Wistar rats using inductively coupled plasma mass spectrometry (ICP-MS), and their maps were illustrated in color to visually compare the distribution of the elements at various stages of the growth process. Sagittal

Tohru Tarohda; Masayoshi Yamamoto; Ryohei Amamo

2004-01-01

233

Absorption of gaseous oxygen by liquid cobalt, copper, iron and nickel  

Microsoft Academic Search

An experimental investigation of the rates of oxygen solution in molten cobalt, copper, iron and nickel was carried out using\\u000a pure oxygen and a constant-volume Sieverts' method. It was found that the volume of gaseous oxygen which initially reacted\\u000a with the inductively stirred metals was strongly dependent on the physical nature of the oxide film which formed during the\\u000a first

R. H. Radzilowski; R. D. Pehlke

1978-01-01

234

Absorption of gaseous oxygen by liquid cobalt, copper, iron and nickel  

Microsoft Academic Search

An experimental investigation of the rates of oxygen solution in molten cobalt, copper, iron and nickel was carried out using\\u000a pure oxygen and a constant-volume Sieverts’ method. It was found that the volume of gaseous oxygen which initially reacted\\u000a with the inductively stirred metals was strongly dependent on the physical nature of the oxide film which formed during the\\u000a first

R. H. Radzilowski; R. D. Pehlke

1978-01-01

235

Determination of lead, copper, zinc, magnesium, calcium and iron in fresh eggs by atomic absorption spectrometry  

Microsoft Academic Search

In this study, lead, copper and zinc, calcium, magnesium and iron in fresh egg samples have been determined by electrothermal and flame atomic absorption spectrometry (ETAAS–FAAS) with Zeeman-effect background correction. Y+Pd+citric acid (CA) has been found a powerful modifier mixture for the determination of Pb, Cu and Zn. Maximum pyrolysis and optimum atomization temperatures of analyte elements were determined in

Ziya Kiliç; Orhan Acar; Mehmet Ula?an; Murat Ilim

2002-01-01

236

Evidence that intrinsic iron but not intrinsic copper determines S-nitrosocysteine decomposition in buffer solution  

Microsoft Academic Search

The present experiments were designed to analyze the influence of copper and iron ions on the process of decomposition of S-nitrosocysteine (cysNO), the most labile species among S-nitrosothiols (RSNO). CysNO fate in buffer solution was evaluated by optical and electron paramagnetic resonance (EPR) spectroscopy, and the consequences on its vasorelaxant effect were studied on noradrenaline-precontracted rat aortic rings. The main

Anatoly F. Vanin; Bernard Muller; Jacicarlos L. Alencar; Irina I. Lobysheva; Françoise Nepveu; Jean-Claude Stoclet

2002-01-01

237

Presence of acute phase changes in zinc, iron, and copper metabolism in turkey embryos  

SciTech Connect

Acute phase changes in trace mineral metabolism were examined in turkey embryos. An endotoxin injection resulted in increased concentrations of serum copper and liver zinc and decreased concentrations of serum zinc in embryos incubated either in ovo or ex ovo. Changes in zinc and copper metabolism occurred when endotoxin either was injected intramuscularly, into the amnionic fluid, or administered onto the chorioallantoic membrane. Unlike poults, embryos did not respond to an inflammatory challenge with decreased serum iron concentrations. Acute phase changes in embryo serum zinc and copper as well as liver zinc concentrations were similar to those in poults. Increased liver zinc concentrations were associated with increased zinc in metallothionein (MT). An injection of a crude interleukin 1 preparation into embryos resulted in similar increases in hepatic zinc and MT concentrations as an endotoxin injection, suggesting a role for this cytokine in mediating the acute phase changes in embryonic zinc metabolism.

Klasing, K.C.; Richards, M.P.; Darcey, S.E.; Laurin, D.E.

1987-01-01

238

Survival and hepatic metallothionein in developing rainbow trout exposed to a mixture of zinc, copper, and cadmium  

SciTech Connect

Rainbow trout (Salmo gairdneri) in Buttle Lake on Vancouver Island, B.C. are exposed to metal contamination originating from a copper and zinc mining operation at Myra Falls near the head of the lake. In order to properly assess the risk to a population of rainbow trout in Buttle Lake, the authors initiated a long-term exposure of rainbow trout from hatch including the swim-up stage. Copper, zinc or cadmium are known to induce metallothionein in mammals and as a mixture of metals, induce hepatic metallothionein in rainbow trout. Investigation of hepatic metallothionein concentrations in wild rainbow trout from Buttle Lake and in lakes of the Campbell River downstream showed a correlation with metal concentrations in the water. Rainbow trout held in situ for 4 weeks showed the same correlation. In this report they determined whether or not the degree of contamination was correlated with concentrations of metallothionein in the livers of rainbow trout exposed to the mixture of metals during the early life stages.

Roch, M.; McCarter, J.A.

1986-02-01

239

Effects of Copper and Cadmium on Lipogenic Metabolism and Metal Element Composition in the Javelin Goby (Synechogobius hasta) After Single and Combined Exposure.  

PubMed

The present study was performed to determine the effects of single and combined exposure of copper (Cu) and cadmium (Cd) on lipogenic metabolism and metal element composition of javelin goby Synechogobius hasta. Two hundred and forty uniform-sized S. hasta (initial mean weight 20.3 ± 0.3 g [mean ± SEM throughout]; initial body length 15.2 ± 0.2 cm) were randomly assigned to 12 fiberglass tanks (water volume 300 l) with 20 fish/tank. The fish were exposed to four treatments with different Cu and Cd concentration for 30 days, respectively: (1) control (without extra Cu and Cd addition), (2) Cu (nominal concentrations of 77 ?g/l), (3) Cd (79 ?g/l), and (4) Cu + Cd (Cu/Cd coexposure). Growth decreased, but hepatosomatic index, viscerosomatic index, and lipid content increased after metal exposure. Staining with Oil Red O and haematoxylin and eosin showed extensive alterations in liver of metals-exposed fish. Metal exposure influenced the accumulation of metal elements (Cu, Cd, iron, zinc, and manganese) in several tissues (muscle, gill, intestine, liver, and spleen) and increased hepatic 6-phosphogluconate dehydrogenase, glucose-6-phosphate dehydrogenase, malic enzyme, isocitrate dehydrogenase, and fatty acid synthase activities. The results of the present study indicated that the changes in lipogenic metabolism and metal element compositions of fish under Cu and Cd coexposure could not be explained by synergism of the addition of the effects observed in singly Cu- or Cd-exposed fish. To our knowledge the present study, for the first time, investigated the effects of Cu and Cd coexposure on hepatic lipogenic metabolism and metal element compositions in a wide range of tissues and organs in fish, which provided new evidence for Cu and Cd interactions in fish. PMID:24595737

Song, Yu-Feng; Luo, Zhi; Pan, Ya-Xiong; Liu, Xu; Huang, Chao; Chen, Qi-Liang

2014-08-01

240

An Electron Paramagnetic Resonance Spectroscopic Study of Copper Hopping in Doped Bis(L-histidinato)cadmium Dihydrate  

PubMed Central

Electron Paramagnetic Resonance (EPR) spectroscopy was used to study Cu(II) dynamic behavior in a doped biological model crystal; bis(L-histidinato)cadmium dihydrate, in order to gain better insight into copper site stability in metalloproteins. Temperature dependent changes in the low temperature X-band EPR spectra became visible around 100 K and continued up to room temperature. The measured 298 K g-tensor (principal values: 2.17, 2.16, 2.07) and copper hyperfine coupling tensor (principal values: ?260, ? 190, ?37 MHz) were similar to the average of the 77 K tensor values pertaining to two neighboring histidine binding sites. The observed temperature dependence was interpreted using Anderson’s theory of motional narrowing, where the magnetic parameters for the different states are averaged as the copper rapidly hops between sites. The EPR pattern was also found to undergo a sharp sigmoidal-shaped, temperature dependent conversion between two species with a critical temperature Tc ? 160 K. The species below Tc hops between the two low temperature site patterns, and the one above Tc represents an average of the molecular spin Hamiltonian coupling tensors of the two 77 K sites. In addition, the low and high temperature species hop between one another, contributing to the dynamic averaging. Spectral simulations using this 4-state model determined a hop rate between the two low temperature sites ?h4 = 4.5 × 108 s?1 and between the low and high temperature states ?h2 = 1.7 × 108 s?1 at 160 K. An Arrhenius relationship of hop rate and temperature gave energy barriers of ?E4 = 389 cm?1 and ?E2 = 656 cm?1 between the two low temperature sites, and between the low and high temperature states, respectively.

Colaneri, Michael J.; Vitali, Jacqueline; Kirschbaum, Kristin

2013-01-01

241

Radiotracer study of the adsorption of organic compounds on gold. adsorption of chloroacetic and phenylacetic acid, and the effects of cadmium, copper, and silver adatoms on it  

SciTech Connect

This paper studies the adsorption of monochloroacetic and phenylacetic acid (MA and PA, respectively) by the radiotracer technique on gold-plated gold electrodes in acidic solutions. The authors also study the effect of cadmium, copper, and silver adatoms on these processes. The adsorption of MA was measured as a function of potential of the electrode. Data from these measurements are presented. Data show that cadmium, copper, and silver ions present in the solution have no effect on the adsorption of PA at potentials where they are not adsorbed on the gold surface. It is confirmed that the radiotracer technique will be as effective in adsorption studies on the gold-plated gold electrode as it was in the case of the platinized platinum electrode.

Horani, G.; Andreev, V.N.; Vazarinov, V.E.

1986-04-01

242

Comparative acute toxicity of gallium(III), antimony(III), indium(III), cadmium(II), and copper(II) on freshwater swamp shrimp (Macrobrachium nipponense)  

PubMed Central

Background Acute toxicity testing were carried out the freshwater swamp shrimp, Macrobrachium nipponense, as the model animal for the semiconductor applied metals (gallium, antimony, indium, cadmium, and copper) to evaluate if the species is an suitable experimental animal of pollution in aquatic ecosystem. Results The static renewal test method of acute lethal concentrations determination was used, and water temperature was maintained at 24.0?±?0.5°C. Data of individual metal obtained from acute toxicity tests were determined using probit analysis method. The median lethal concentration (96-h LC50) of gallium, antimony, indium, cadmium, and copper for M. nipponense were estimated as 2.7742, 1.9626, 6.8938, 0.0539, and 0.0313 mg/L, respectively. Conclusions Comparing the toxicity tolerance of M. nipponense with other species which exposed to these metals, it is obviously that the M. nipponense is more sensitive than that of various other aquatic animals.

2014-01-01

243

Molecular evidence and physiological characterization of iron absorption in isolated enterocytes of rainbow trout (Oncorhynchus mykiss): implications for dietary cadmium and lead absorption.  

PubMed

Recent studies suggested the probable involvement of an apical iron (Fe(2+)) transporter, the divalent metal transporter-1 (DMT1), in the uptake of several divalent metals in fish. The present study examined the gastrointestinal expression of the DMT1 gene, and investigated the kinetics of Fe(2+) uptake and its interactions with cadmium and lead in isolated enterocytes of freshwater rainbow trout (Oncorhynchus mykiss). The expressions of two DMT1 isoforms (Nramp-beta and -gamma) were recorded along the entire gastrointestinal tract of fish as well as in the enterocytes. Fe(2+) uptake in isolated enterocytes was saturable and sensitive to the proton gradient and membrane potential, suggesting DMT1-mediated transport. Both cadmium and lead inhibited Fe(2+) uptake in isolated enterocytes in a concentration-dependent manner, and lead appeared to be a stronger inhibitor than cadmium. The kinetic characterization of Fe(2+) uptake revealed that the apparent affinity of uptake was significantly decreased (increased K(m)) in the presence of either cadmium or lead, whereas the maximum uptake rate (J(max)) remained unchanged-indicating that the interaction between Fe(2+) and cadmium or lead is competitive in nature. Overall, our study suggests that the uptake of dietary cadmium and lead may occur via the iron-transporting pathway in fish. PMID:20541816

Kwong, Raymond W M; Andrés, Jose A; Niyogi, Som

2010-09-01

244

Copper, Cadmium, and Zinc Concentrations in Juvenile Chinook Salmon and Selected Fish-Forage Organisms (Aquatic Insects) in the Upper Sacramento River, California  

Microsoft Academic Search

This study assessed the downstream extent andseverity of copper (Cu), cadmium (Cd), and zinc (Zn)contamination from acid mine drainage on juvenile chinook salmon(Oncorhynchus tshawytscha) and aquatic insects over aroughly 270-km reach of the Sacramento River below KeswickReservoir. During April–May 1998, salmon were collected fromfour sites in the river and from a fish hatchery that receiveswater from Battle Creek. Salmon from

Michael K. Saiki; Barbara A. Martin; Larry D. Thompson; Daniel Welsh

2001-01-01

245

Fabrication of cadmium sulfide-copper sulfide thin film solar cells by an all vacuum deposited process and their related studies  

Microsoft Academic Search

An in situ resistance measurement technique which was used to study the CdS and Cu\\/sub x\\/S films by monitoring their resistances during and after evaporation of the cadmium sulfide and the copper sulfide is described. A simple mathematical procedure was used to calculate the thickness and resistivity of the films. Thin film CdS-Cu\\/sub x\\/S solar cells were prepared using an

Cao

1982-01-01

246

The toxic action and interactions of copper and cadmium to the marine Alga Dunaliella minuta , in both acute and chronic exposure  

Microsoft Academic Search

The effective concentrations of copper and cadmium which reduced the population growth ofDunaliella minuta by 50% after 96 h of static exposure, were determined to be 7.57 µM Cu and 0.34 µM Cd. Short-term static exposure to both metals indicated that their combined action is antagonistic with respect to growth of this chlorophyte. Additionally, long-term exposure to low levels of

Ioanna Visviki; Joseph W. Rachlin

1991-01-01

247

Trace Element Concentrations (Mercury, Cadmium, Copper, Zinc, Lead, Aluminium, Nickel, Arsenic, and Selenium) in Some Aquatic Birds of the Southwest Atlantic Coast of France  

Microsoft Academic Search

Trace elements (mercury [Hg], cadmium [Cd], copper [Cu], zinc [Zn], lead [Pb], aluminium [Al], nickel [Ni], arsenic [As],\\u000a and selenium [Se]) were investigated using inductively coupled plasma–mass spectrometry in liver, kidney, muscle, and feather\\u000a of aquatic birds wintering or inhabiting the wetlands situated on the Southwest Atlantic coast of France. A majority of greylag\\u000a geese, red knots, and grey plovers

Magali Lucia; Jean-Marc André; Karine Gontier; Nicolas Diot; Jesus Veiga; Stéphane Davail

2010-01-01

248

A comparative study of thermal behavior of iron and copper nanofluids  

NASA Astrophysics Data System (ADS)

Nanofluids consist of nanoparticles dispersed in heat transfer carrier fluid and are typically used for enhancing thermal conductivity in devices and systems. This study investigated the synthesis of iron and copper nanoparticle-based thermal fluids prepared using a two-step process. Chemical precipitation was used for the synthesis of the powders, and ultrasonic irradiation was used to disperse the nanoparticles in the carrier fluid (ethylene glycol). The size distributions of the nanopowders in the carrier fluid were determined using dynamic light scattering resulting in average particle sizes of around 500 nm. The crystallite sizes of the powders were below 20 nm. Thus, both types of nanofluids are comparable with regard to crystallite size, particle size, and morphology resulting in a direct comparison of material properties and their effect on thermal conductivity of the nanofluids. A guarded hot parallel-plate method and dynamic tests were used to compare the thermal conductivities of the nanofluids. It was shown that thermal conductivity can be enhanced by up to 70% for copper nanofluids. It was also demonstrated that for a given particle concentration, copper nanofluids are superior in thermal conductivity compared to iron nanofluids.

Sinha, Kaustav; Kavlicoglu, Barkan; Liu, Yanming; Gordaninejad, Faramarz; Graeve, Olivia A.

2009-09-01

249

Iron deficiency enhances cadmium uptake and translocation mediated by the Fe transporters OsIRT1 and OsIRT2 in rice  

Microsoft Academic Search

Cadmium (Cd) accumulation in rice grains is enhanced if ponded water is released from paddy fields during the reproductive stage (intermittent irrigation). The release of ponded water creates aerobic soil conditions under which Cd becomes soluble and iron (Fe) solubility decreases. We hypothesized that Fe shortage in rice induces Fe uptake and translocation and that Cd is also taken up

Hiromi Nakanishi; Ippei Ogawa; Yasuhiro Ishimaru; Satoshi Mori; Naoko K. Nishizawa

2006-01-01

250

Zebrafish in the sea of mineral (iron, zinc, and copper) metabolism.  

PubMed

Iron, copper, zinc, and eight other minerals are classified as essential trace elements because they present in minute in vivo quantities and are essential for life. Because either excess or insufficient levels of trace elements can be detrimental to life (causing human diseases such as iron-deficiency anemia, hemochromatosis, Menkes syndrome and Wilson's disease), the endogenous levels of trace minerals must be tightly regulated. Many studies have demonstrated the existence of systems that maintain trace element homeostasis, and these systems are highly conserved in multiple species ranging from yeast to mice. As a model for studying trace mineral metabolism, the zebrafish is indispensable to researchers. Several large-scale mutagenesis screens have been performed in zebrafish, and these screens led to the identification of a series of metal transporters and the generation of several mutagenesis lines, providing an in-depth functional analysis at the system level. Moreover, because of their developmental advantages, zebrafish have also been used in mineral metabolism-related chemical screens and toxicology studies. Here, we systematically review the major findings of trace element homeostasis studies using the zebrafish model, with a focus on iron, zinc, copper, selenium, manganese, and iodine. We also provide a homology analysis of trace mineral transporters in fish, mice and humans. Finally, we discuss the evidence that zebrafish is an ideal experimental tool for uncovering novel mechanisms of trace mineral metabolism and for improving approaches to treat mineral imbalance-related diseases. PMID:24639652

Zhao, Lu; Xia, Zhidan; Wang, Fudi

2014-01-01

251

Effects of selenium on liver and muscle contents and urinary excretion of zinc, copper, iron and manganese.  

PubMed

Selenium is a main component of glutathione peroxidase (GPX), a key antioxidant enzyme. Other elements, such as zinc, copper, manganese and iron, are also involved in the pathogenesis of oxidative damage as well as in other important metabolic pathways. The effects of selenium supplementation on the metabolism of these elements have yield controversial results .The aim of this study is to analyse the effects of selenium supplementation on liver, muscle and urinary excretion of zinc, copper, iron and manganese in a situation of oxidative stress, such as protein deficiency. The experimental design included four groups of adult male Sprague-Dawley rats, which received the Lieber-DeCarli control diet, an isocaloric 2 % protein-containing diet and another similar two groups to which selenomethionine (6 mg/l liquid diet) was added. After sacrifice (5 weeks later), muscle, liver and serum selenium were determined, as well as muscle, liver and urinary zinc, copper, manganese and iron and liver GPX activity and liver malondialdehyde. Selenium addition led to decreased liver copper, increased muscle copper, increased copper excretion and increased liver iron, whereas zinc and manganese parameters were essentially unaltered. Muscle, liver and serum selenium were all significantly correlated with liver GPX activity. PMID:24622908

Monedero-Prieto, María José; González-Pérez, José María; González-Reimers, Emilio; Hernández-Pérez, Onán; Monereo-Muñoz, María; Galindo-Martín, Luis; Quintero-Platt, Geraldine; Abreu-González, Pedro

2014-05-01

252

Copper, iron and zinc absorption, retention and status of young women fed vitamin B-6 deficient diets  

SciTech Connect

A study was conducted in young women to determine the effect of vitamin B-6 deficient diets on copper, iron and zinc metabolism. Young women were confined to a metabolic research unit for 84 and 98 days. They were fed a vitamin B-6 deficient formula diet initially, followed by food diet containing four increasing levels of vitamin B-6. Copper, iron and zinc absorption, retention and status were determined at intervals throughout the study. Absorption was determined using the stable isotopes {sup 65}Cu, {sup 54}Fe, and {sup 67}Zn. Status was based on serum copper and zinc, hemoglobin, hematocrit and mean corpuscular volume. Copper absorption averaged 18 {plus minus} 1% during vitamin B-6 depletion, significantly lower than 24 {plus minus} 1% during repletion, but serum copper was not affected and balance was positive. Iron absorption was not impaired significantly by vitamin B-6 deficient diets, but status declined during the depletion period. Zinc absorption averaged 40 {plus minus} 2% during depletion and 27 {plus minus} 2% during repletion. Zinc absorption and retention were significantly greater during vitamin B-6 depletion, but serum zinc declined suggesting the absorbed zinc was not available for utilization. The results suggest that vitamin B-6 depletion of young women may inhibit copper absorption, affect iron status and alter zinc metabolism. The effects of vitamin B-6 depletion differ markedly among these elements.

Turnlund, J.R.; Keyes, W.R.; Hudson, C.A.; Betschart, A.A.; Kretsch, M.J.; Sauberlich, H.E. (USDA/ARS, San Francisco, CA (United States) Western Regional Research Center, Albany, CA (United States))

1991-03-11

253

Behavior of cadmium, lead and zinc at the sediment–water interface by electrochemically initiated processes  

Microsoft Academic Search

Nowadays, electrokinetic remediation is one of the popular and cheapest in situ remediation techniques for contaminated soils. This method uses a low-level electrical energy and is known for removal of heavy metals like, cadmium, chromium, copper, iron, lead, mercury, nickel, zinc and the metalloid arsenic from polluted and spiked soils. The driving force is the migration of those ions in

Reena Shrestha; R. Fischer; D. Rahner

2003-01-01

254

a Study of Thin-Film Polycrystalline Cadmium-Sulphide - Copper-Sulphide Solar Cells and Copper-Sulphide Thin -  

NASA Astrophysics Data System (ADS)

Our work was done as two distinct parts. In the first part we studied the effects of heat treatments on three Cu(,x)S thin films (1.995 (LESSTHEQ) x (LESSTHEQ) 2). Our results suggest that initial heat treatments cause copper in grain boundaries to diffuse irreversibly into the Cu(,x)S crystallites. Subsequent heating in hydrogen causes a reduction in surface oxides while the reverse process occurs in an oxygen atmosphere. At a given elevated temperature (usually 150(DEGREES)C), the resistivity ((rho)) and charge density ((RHO)) vary with time according to the expressions (RHO) = (RHO)(,o)e('(+OR-)SQRT.(t/(tau)) and (rho) = (rho)(,o)e('(+OR-)SQRT.(t/(tau)). On the other hand, the mobility is found to be approximately constant at a given temperature. Changes in Cu(,x)S stoichiometry were correlated with the sheet resistance of the Cu(,x)S layer in completed cells. Results indicate that heat treatment in a hydrogen atmosphere causes an increase in resistivity (corresponding to an increase in stoichiometry) while oxygen causes the reverse. The effects of hydrogen heat treatments are reported on CdS/Cu(,x)S polycrystalline thin-film solar cells. The short-circuit current (I(,sc)) of the cells changes in an exponential manner such that I(,sc) = I(,sc)(t=0)e('SQRT.(t/(tau)). The principle physical mechanism responsible for this change appears to be copper diffusion through the Cu(,x)S layer as copper oxides at the surface are reduced or formed. We were able to maximize the cell efficiency with an error of less than 5 per cent by monitoring changes in cell parameters during heat treatments. The second part of our work was concerned with studies of the capacitance of completed CdS/Cu(,x)S solar cells. Measurements of the dark capacitance of CdS cells as a function of the frequency of the applied signal voltage have shown that the capacitance varies with frequency according to the relation. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). where (tau) is the time constant associated with interfacial and deep bulk states. Photocapacitance studies show that the CdS cell can be treated according to the frequency dependent model of Schibli and Milnes. Under the influence of light C (TURN) 1/SQRT.((omega). Further work demonstrates that the simple planar junction model most often used to describe the CdS cell is accurate at high frequencies. Also, we studied A.C. capacitance measurements taken as a function of reverse bias voltage and signal frequency on four thin-film CdS/Cu(,x)S solar cells and one single crystal cell. Our results suggest the presence of at least two trapping states in the i-layer formed by the presence of Cu impurities in CdS. The deep traps produce anomalies in the normally linear 1/C('2) versus V plots. The energies of the states were found by measuring the particular bias voltages at which anomalies were observed. Other results concerning the anomalous behavior in CdS cells and their relation to the work of Roberts and Crowell are also discussed. These include variations of capacitance with frequency and temperature, and changes in shunt conductance with frequency. *All degree requirements completed in 1980, but degree will be granted in 1981.

Hmurcik, Lawrence Vincent

255

Shift of the Fermi level during cointercalation of copper and iron into TiSe2  

NASA Astrophysics Data System (ADS)

The influence of copper intercalation into the TiSe2 compound on the Fermi energy has been investigated using two independent methods. The first method is based on the analysis of the amplitude of the deformation (induced by impurity intercalation and providing the formation of polarons) as a function of the binding energy of the band of polaron states. For this purpose, the Fe x Cu y TiSe2 system has been synthesized for the first time by cointercalation of copper and iron into the TiSe2 lattice and studied. The second method consists in measuring the electromotive force of an open-circuit electrochemical cell with respect to a metal reference electrode. Both methods lead to consistent results in the range of moderate copper contents. However, considerable discrepancies have been observed in the copper concentration range that corresponds to the beginning of filling of Cu/Ti hybrid states. These discrepancies are explained by the softening of the lattice due to an increase in the density of states at the Fermi level.

Titov, A. A.; Titov, A. N.; Bushkova, O. V.; Tsurin, V. A.

2010-08-01

256

The role of iron and copper molecules in the neuronal vulnerability of locus coeruleus and substantia nigra during aging  

PubMed Central

In this study, a comparative analysis of metal-related neuronal vulnerability was performed in two brainstem nuclei, the locus coeruleus (LC) and substantia nigra (SN), known targets of the etiological noxae in Parkinson's disease and related disorders. LC and SN pars compacta neurons both degenerate in Parkinson's disease and other Parkinsonisms; however, LC neurons are comparatively less affected and with a variable degree of involvement. In this study, iron, copper, and their major molecular forms like ferritins, ceruloplasmin, neuromelanin (NM), manganese-superoxide dismutase (SOD), and copper/zinc-SOD were measured in LC and SN of normal subjects at different ages. Iron content in LC was much lower than that in SN, and the ratio heavy-chain ferritin/iron in LC was higher than in the SN. The NM concentration was similar in LC and SN, but the iron content in NM of LC was much lower than SN. In both regions, heavy- and light-chain ferritins were present only in glia and were not detectable in neurons. These data suggest that in LC neurons, the iron mobilization and toxicity is lower than that in SN and is efficiently buffered by NM. The bigger damage occurring in SN could be related to the higher content of iron. Ferritins accomplish the same function of buffering iron in glial cells. Ceruloplasmin levels were similar in LC and SN, but copper was higher in LC. However, the copper content in NM of LC was higher than that of SN, indicating a higher copper mobilization in LC neurons. Manganese-SOD and copper/zinc-SOD had similar age trend in LC and SN. These results may explain at least one of the reasons underlying lower vulnerability of LC compared to SN in Parkinsonian syndromes.

Zecca, Luigi; Stroppolo, Antonella; Gatti, Alberto; Tampellini, Davide; Toscani, Marco; Gallorini, Mario; Giaveri, Giuseppe; Arosio, Paolo; Santambrogio, Paolo; Fariello, Ruggero G.; Karatekin, Erdem; Kleinman, Mark H.; Turro, Nicholas; Hornykiewicz, Oleh; Zucca, Fabio A.

2004-01-01

257

Bioavailability of Iron, Lead, and Cadmium Via Gastrointestinal Absorption: A Review.  

National Technical Information Service (NTIS)

Numerous factors may act to increase or decrease the biologic availability of heavy metals. The precise mechanisms controlling gastrointestinal absorption are unknown, even for an essential element as extensively studied as iron. For iron there is substan...

H. A. Ragan

1981-01-01

258

Arabidopsis Copper Transport Protein COPT2 Participates in the Cross Talk between Iron Deficiency Responses and Low-Phosphate Signaling1[C][W  

PubMed Central

Copper and iron are essential micronutrients for most living organisms because they participate as cofactors in biological processes, including respiration, photosynthesis, and oxidative stress protection. In many eukaryotic organisms, including yeast (Saccharomyces cerevisiae) and mammals, copper and iron homeostases are highly interconnected; yet, such interdependence is not well established in higher plants. Here, we propose that COPT2, a high-affinity copper transport protein, functions under copper and iron deficiencies in Arabidopsis (Arabidopsis thaliana). COPT2 is a plasma membrane protein that functions in copper acquisition and distribution. Characterization of the COPT2 expression pattern indicates a synergic response to copper and iron limitation in roots. We characterized a knockout of COPT2, copt2-1, that leads to increased resistance to simultaneous copper and iron deficiencies, measured as reduced leaf chlorosis and improved maintenance of the photosynthetic apparatus. We propose that COPT2 could play a dual role under iron deficiency. First, COPT2 participates in the attenuation of copper deficiency responses driven by iron limitation, possibly to minimize further iron consumption. Second, global expression analyses of copt2-1 versus wild-type Arabidopsis plants indicate that low-phosphate responses increase in the mutant. These results open up new biotechnological approaches to fight iron deficiency in crops.

Perea-Garcia, Ana; Garcia-Molina, Antoni; Andres-Colas, Nuria; Vera-Sirera, Francisco; Perez-Amador, Miguel A.; Puig, Sergi; Penarrubia, Lola

2013-01-01

259

Electrodeposition and Characterization of Nickel, Iron, Copper Thin Films and the Creation of Nanoporous Structures  

NASA Astrophysics Data System (ADS)

There has been much research in creating nanoporous platinum or gold thin films for catalysis, but there has not been as much work done with other, less noble metals. This research explored the deposition of nickel, iron, and copper ternary alloys using controlled potential electrolysis (CPE) and the selective removal of the copper with DC potential amperometry (DCPA) and linear sweep voltammetry (LSV) to create nanoporous structures. These structures have the advantage of increased surface area creating more efficient catalysts. All films were characterized before and after dealloying using scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS) for composition. The roughness of each of the films was characterized by the capacitance of the film, with higher capacitances indicating a higher electrochemical surface area.

Yarranton, Jonathan; Hampton, Jennifer

2013-03-01

260

Relationship between Paratuberculosis and the microelements Copper, Zinc, Iron, Selenium and Molybdenum in Beef Cattle  

PubMed Central

To study the deficiency of minerals and its relationship with Paratuberculosis, blood, serum, and fecal samples were obtained from 75 adult bovines without clinical symptoms of the disease and from two bovines with clinical symptoms of the disease, from two beef herds with a previous history of Paratuberculosis in the Province of Buenos Aires, Argentina. Serum samples were processed by ELISA and feces were cultured in Herrolds medium. Copper, zinc and iron in serum were quantified by spectrophotometry and selenium was measured by the activity of glutathione peroxidase. We also determined copper, zinc, iron and molybdenum concentrations in pastures and the concentration of sulfate in water. Mycobacterium avium subsp paratuberculosis (Map) was isolated from 17.3% of fecal samples of asymptomatic animals and from the fecal samples from the two animals with clinical symptoms. All the Map-positive animals were also ELISA-positive or suspect, and among them, 84.6% presented low or marginal values of selenium and 69.2% presented low or marginal values of copper. The two animals with clinical symptoms, and isolation of Map from feces and organs were selenium-deficient and had the lowest activity of glutathione peroxidase of all the animals from both herds. All the animals negative to Map in feces and negative to ELISA had normal values of Se, while 13.8% of animals with positive ELISA or suspect and culture negative presented low levels of Se. Half of the animals that were negative both for ELISA and culture in feces were deficient in copper but none of them presented low values of selenium. The content of molybdenum and iron in pasture was high, 2.5 ppm and 1.13 ppm in one herd and 2.5 ppm and 2.02 ppm in the other, respectively, whereas the copper:molybdenum ratio was 1.5 and 5.2, respectively. These results do not confirm an interaction between imbalances of the micronutrients and clinical Paratuberculosis, but show evidence of the relationship between selenium deficiencies in animals with Map infection and ELISA positive results.

Paolicchi, F.; Perea, J.; Cseh, S.; Morsella, C.

2013-01-01

261

Relationship between Paratuberculosis and the microelements Copper, Zinc, Iron, Selenium and Molybdenum in Beef Cattle.  

PubMed

To study the deficiency of minerals and its relationship with Paratuberculosis, blood, serum, and fecal samples were obtained from 75 adult bovines without clinical symptoms of the disease and from two bovines with clinical symptoms of the disease, from two beef herds with a previous history of Paratuberculosis in the Province of Buenos Aires, Argentina. Serum samples were processed by ELISA and feces were cultured in Herrolds medium. Copper, zinc and iron in serum were quantified by spectrophotometry and selenium was measured by the activity of glutathione peroxidase. We also determined copper, zinc, iron and molybdenum concentrations in pastures and the concentration of sulfate in water. Mycobacterium avium subsp paratuberculosis (Map) was isolated from 17.3% of fecal samples of asymptomatic animals and from the fecal samples from the two animals with clinical symptoms. All the Map-positive animals were also ELISA-positive or suspect, and among them, 84.6% presented low or marginal values of selenium and 69.2% presented low or marginal values of copper. The two animals with clinical symptoms, and isolation of Map from feces and organs were selenium-deficient and had the lowest activity of glutathione peroxidase of all the animals from both herds. All the animals negative to Map in feces and negative to ELISA had normal values of Se, while 13.8% of animals with positive ELISA or suspect and culture negative presented low levels of Se. Half of the animals that were negative both for ELISA and culture in feces were deficient in copper but none of them presented low values of selenium. The content of molybdenum and iron in pasture was high, 2.5 ppm and 1.13 ppm in one herd and 2.5 ppm and 2.02 ppm in the other, respectively, whereas the copper:molybdenum ratio was 1.5 and 5.2, respectively. These results do not confirm an interaction between imbalances of the micronutrients and clinical Paratuberculosis, but show evidence of the relationship between selenium deficiencies in animals with Map infection and ELISA positive results. PMID:24159298

Paolicchi, F; Perea, J; Cseh, S; Morsella, C

2013-01-01

262

Shock compression of highly porous samples of copper, iron, nickel and their equation of state  

SciTech Connect

Shock compressibility of copper, iron and nickel samples is studied whose initial density was 5-20 times less than the normal up to {approx}90 GPa pressures. The porous samples were produced from fine-grain powder with sizes of separate grains being several hundreds 0.2-0.3 nm. Explosive generators producing planar and spherical shock waves in the samples were used for the shock loading. The results found are compared with the computations with the semi-empirical equation of state of metals of a variable nuclei and electrons heat capacity.

Trunin, R. F.; Zhernokletov, M. V.; Simakov, G. V.; Gudarenko, L. F.; Gushchina, O. N. [Russian Federal Nuclear Center-VNIIEF, Sarov (Russian Federation)

1998-07-10

263

Optimal copper supply is required for normal plant iron deficiency responses.  

PubMed

Iron (Fe) and copper (Cu) homeostasis are tightly linked across biology. Understanding crosstalk between Fe and Cu nutrition could lead to strategies for improved growth on soils with low or excess metals, with implications for agriculture and phytoremediation. Here, we show that Cu and Fe nutrition interact to increase or decrease Fe and/or Cu accumulation in leaves and Fe uptake processes. Leaf Cu concentration increased under low Fe supply, while high Cu lowered leaf Fe concentration. Ferric reductase activity, an indicator of Fe demand, was inhibited at insufficient or high Cu supply. Surprisingly, plants grown without Fe were more susceptible to Cu toxicity. PMID:24084753

Waters, Brian M; Armbrust, Laura C

2013-12-01

264

Optimal copper supply is required for normal plant iron deficiency responses  

PubMed Central

Iron (Fe) and copper (Cu) homeostasis are tightly linked across biology. Understanding crosstalk between Fe and Cu nutrition could lead to strategies for improved growth on soils with low or excess metals, with implications for agriculture and phytoremediation. Here, we show that Cu and Fe nutrition interact to increase or decrease Fe and/or Cu accumulation in leaves and Fe uptake processes. Leaf Cu concentration increased under low Fe supply, while high Cu lowered leaf Fe concentration. Ferric reductase activity, an indicator of Fe demand, was inhibited at insufficient or high Cu supply. Surprisingly, plants grown without Fe were more susceptible to Cu toxicity.

Waters, Brian M; Armbrust, Laura C

2013-01-01

265

Iron as a possible aggravating factor for osteopathy in itai-itai disease, a disease associated with chronic cadmium intoxication  

SciTech Connect

Itai-itai disease is thought to be the result of chronic cadmium (Cd) intoxication. We examined 23 autopsy cases of itai-itai disease and 18 cases of sudden death as controls. Urine and blood samples from 10 patients were collected before they died and revealed the presence of severe anemia and renal tubular injuries. Undecalcified sections of iliac bone were stained with Aluminon reagent, and ammonium salt of aurintricarboxylic acid, and Prussian blue reagent in all cases of itai-itai disease. These two reagents reacted at the same mineralization fronts. X-ray microanalysis revealed the presence of iron at mineralization fronts in itai-itai disease. Five patients showed evidence of hemosiderosis in the liver, spleen, and pancreas, probably as a result of post transfusion iron overload. Renal calculi and calcified aortic walls were also stained with Prussian blue reagent in several patients. Neither ferritin nor transferrin were visualized at mineralization fronts in itai-itai disease by immunohistochemical staining. These results suggest that iron is bound to calcium or to calcium phosphate by a physicochemical reaction. A marked osteomalacia was observed in 10 cases of itai-itai disease by histomorphometry. Regression analyses of data from cases of itai-itai disease suggested that an Aluminon-positive metal inhibited mineralization and that renal tubules were injured. Since bone Cd levels were increased in itai-itai disease, it is likely that renal tubules were injured by exposure to Cd. Therefore, stainable bone iron is another possible aggravating factor for osteopathy in itai-itai disease, and a synergistic effect between iron and Cd on mineralization is proposed.

Noda, M.; Yasuda, M.; Kitagawa, M. (Toyama Medical and Pharmaceutical Univ. (Japan))

1991-03-01

266

Effect of adsorbed chlorine and oxygen on the shear strength of iron and copper junctions  

NASA Technical Reports Server (NTRS)

Static-friction experiments were performed in ultrahigh vacuum at room temperature on copper, iron, and steel contacts selectively contaminated with oxygen and chlorine in submonolayer amounts. The concentration of the adsorbates was determined with Auger electron spectroscopy and was measured relative to the saturation concentration of oxygen on iron (concentration, 1.0). The coefficient of static friction decreased with increasing adsorbate concentration; however, it was independent of the type of metal and the adsorbate species. The results compared satisfactorily with an extension of the junction growth theory to heterogeneous interfaces. The reduction in interfacial shear strength was measured by the ratio of the shear strength of the interface with an adsorbate concentration of 1.0 and the strength of the clean metal interface. This ratio was about 0.835 for all the systems tested.

Wheeler, D. R.

1976-01-01

267

Effect of adsorbed chlorine and oxygen on shear strength of iron and copper junctions  

NASA Technical Reports Server (NTRS)

Static friction experiments were performed in ultrahigh vacuum at room temperature on copper, iron, and steel contacts selectively contaminated with oxygen and chlorine in submonolayer amounts. The concentration of the adsorbates was determined with Auger electron spectroscopy and was measured relative to the saturation concentration of oxygen on iron (concentration 1.0). The coefficient of static friction decreased with increasing adsorbate concentration. It was independent of the metal and the adsorbate. The results compared satisfactorily with an extension of the junction growth theory to heterogeneous interfaces. The reduction in interfacial shear strength was measured by the ratio sub a/sub m where sub a is the shear strength of the interface with an adsorbate concentration of 1.0, and sub m is the strength of the clean metal interface. This ratio was 0.835 + or - 0.012 for all the systems tested.

Wheeler, D. R.

1975-01-01

268

Comparative study between probe focussed sonication and conventional stirring in the evaluation of cadmium and copper in plants.  

PubMed

Ultrasound (US)-assisted extraction has been widely used for metal ion extraction in plants due to its unique properties of decreased extraction time, minimal contamination, low reagent consumption and low cost. However, very few papers present a sound comparison between probe-focussed sonication and conventional stirring in the evaluation of metal ion extraction in plants. In this study, ultrasonic-assisted digestion has been evaluated and compared to magnetic stirring for total copper and cadmium determination by atomic absorption spectrometry in biological samples (plants, plankton and mussels). The same experimental conditions of sample amount and particle size, extractant solution and extraction time were applied for both ultrasound and magnetic stirring-assisted extraction methods in order to truly compare their effect on metal ion solubilisation. To gain further insight in this issue, dried and fresh plants were tested. The results obtained indicated that osmotic tension in cell walls, produced when dried and powdered samples were immersed in the extractant solution, had an important contribution to metal ion solubilisation, the enhancement due to US for the same purpose being negligible. PMID:20890593

Pereira, Sara; Fonseca, Luís P; Capelo, José L; Armas, Teresa; Vilhena, Fernanda; Pinto, Ana P; Gonçalves, Maria L S; Mota, A M

2010-11-01

269

The role of the kinase OXI1 in cadmium- and copper-induced molecular responses in Arabidopsis thaliana.  

PubMed

The hypothesis that mitogen-activated protein kinase (MAPK) signalling is important in plant defences against metal stress has become accepted in recent years. To test the role of oxidative signal-inducible kinase (OXI1) in metal-induced oxidative signalling, the responses of oxi1 knockout lines to environmentally realistic cadmium (Cd) and copper (Cu) concentrations were compared with those of wild-type plants. A relationship between OXI1 and the activation of lipoxygenases and other initiators of oxylipin production was observed under these stress conditions, suggesting that lipoxygenase-1 may be a downstream component of OXI1 signalling. Metal-specific differences in OXI1 action were observed. For example, OXI1 was required for the up-regulation of antioxidative defences such as catalase in leaves and Fe-superoxide dismutase in roots, following exposure to Cu, processes that may involve the MEKK1-MKK2-WRKY25 cascade. Moreover, the induction of Cu/Zn superoxide dismutases in Cu-exposed leaves was regulated by OXI1 in a manner that involves fluctuations in the expression of miRNA398. These observations contrast markedly with the responses to Cd exposure, which also involves OXI1-independent pathways but rather involves changes in components mediating intracellular communication. PMID:23278806

Smeets, Karen; Opdenakker, Kelly; Remans, Tony; Forzani, Celine; Hirt, Heribert; Vangronsveld, Jaco; Cuypers, Ann

2013-06-01

270

Assessing the Mobility of Lead, Copper and Cadmium in a Calcareous Soil of Port-au-Prince, Haiti †  

PubMed Central

The presence of heavy metals in the environment constitutes a potential source of both soil and groundwater pollution. This study has focused on the reactivity of lead (Pb), copper (Cu) and Cadmium (Cd) during their transfer in a calcareous soil of Port-au-Prince (Haiti). Kinetic, monometal and competitive batch tests were carried out at pH 6.0. Two simplified models including pseudo-first-order and pseudo-second-order were used to fit the experimental data from kinetics adsorption batch tests. A good fit of these data was found with pseudo-second-order kinetic model which indicates the applicability of this model to describe the adsorption rates of these metals on the soil. Monometal batch tests indicated that both Langmuir and Freundlich models allowed a good fit for experimental data. On the basis of the maximum adsorption capacity (qmax), the order affinity of Pb, Cu and Cd for the studied soil was Pb2+ > Cu2+ > Cd2+. Competitive sorption has proved that the competition between two or several cations on soils for the same active sites can decrease their qmax. These results show that, at high metal concentrations, Cd may pose more threat in soils and groundwater of Port-au-Prince than Pb and Cu.

Fifi, Urbain; Winiarski, Thierry; Emmanuel, Evens

2013-01-01

271

Acute and chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures  

USGS Publications Warehouse

White sturgeon (Acipenser transmontanus) are experiencing poor recruitment in the trans boundary reach of the upper Columbia River in eastern Washington State. Limited toxicity data indicated that early life stages of white sturgeon are sensitive to metals. In acute 4-day (d) exposures with larval white sturgeon, previous studies have reported that the 4-day median lethal concentrations (LC50) based on biotic ligand model (BLM) normalization for copper were below the U.S. Environmental Protection Agency national recommended acute water-quality criterion. In previously published chronic 66-d exposures starting with newly fertilized eggs of white sturgeon, 20-percent lethal effect concentrations (LC20s) for copper, cadmium, or zinc generally were within a factor of two of the chronic values of the most sensitive fish species in the databases of the U.S. Environmental Protection Agency water-quality criteria (WQC) for the three metals. However, there were some uncertainties in the chronic exposures previously performed with white sturgeon, including (1) low control survival (37 percent), (2) more control fish tested in each replicate compared to other treatments, (3) limited replication of treatments (n=2), (4) lack of reported growth data (such as dry weight), and (5) wide dilution factors for exposure concentrations (6- to 8-fold dilutions). The U.S. Environmental Protection Agency concluded that additional studies are needed to generate more toxicity data to better define lethal and sublethal toxicity thresholds for metals for white sturgeon. The objective of the study was to further evaluate the acute and chronic toxicity of cadmium, copper, lead, or zinc to early life stages of white sturgeon in water-only exposures. Toxicity tests also were performed with commonly tested rainbow trout (Oncorhynchus mykiss) under similar test conditions to determine the relative sensitivity between white sturgeon and rainbow trout to these metals. Toxicity data generated from this study were used to evaluate the sensitivity of early life stages of white sturgeon and rainbow trout relative to data published for other test organisms. Toxicity data generated from this study also were used to evaluate the level of protection of U.S. Environmental Protection Agency WQC or Washington State water-quality standards (WQS) for copper, zinc, cadmium, or lead to white sturgeon inhabiting the upper Columbia River. Chapter A of this report summarizes the results of acute toxicity tests performed for 4 d with white sturgeon and rainbow trout exposed to copper, cadmium, or zinc. Chapter B of this report summarizes the results of chronic toxicity tests performed for as many as 53 days with white sturgeon or rainbow trout exposed to copper, cadmium, zinc, or lead. Appendixes to the report are available at http://pubs.usgs.gov/sir/2013/5204. Supporting documentation for chapter A toxicity testing is provided in appendix 1. Supporting documentation for chapter B toxicity testing is provided in Appendix 2. Supporting documentation on analysis of water chemistry for chapter A and chapter B is provided in appendix 3 and 4. The rationale for applying corrections to measured copper and zinc values in water samples from some of the toxicity tests performed in chapter A is provided in appendix 5. A summary of dissolved organic carbon measurement variability and implications for biotic ligand model normalization for toxicity data summarized in chapter A and chapter B are provided in appendix 6. An evaluation of an interlaboratory comparison of analyses for dissolved organic carbon in water from the U.S. Geological Survey Columbia Environmental Research Center and University of Saskatchewan is provided in appendix 7. Finally, appendix 8 provides a summary of retesting of white sturgeon in 2012 to determine if improved survival of sturgeon would affect copper effect concentrations in 24-d copper exposures started with newly hatched larvae, and to evaluate the effect of light intensity or temperature on the response of newly hatched larvae during a 25-d study.

Edited by Ingersoll, Christopher G.; Mebane, Christopher A.; Contributions by Wang, Ning; Calfee, Robin D.; Beahan, Erinn; Brumbaugh, William G.; Dorman, Rebecca A.; Hardesty, Doug K.; Ingersoll, Christopher G.; Kunz, James L.; Little, Edward E.; Mebane, Christopher A.; Puglis, Holly J.

2014-01-01

272

Friction and transfer of copper, silver, and gold to iron in the presence of various adsorbed surface films  

NASA Technical Reports Server (NTRS)

Sliding friction experiments were conducted with the noble metals copper, silver, and gold and two binary alloys of these metals contacting iron in the presence of various adsorbates including, oxygen, methyl mercaptan, and methyl chloride. A pin on disk specimen configuration was used with a load of 100 grams, sliding velocity of 60 mm/min; at 25 C with the surfaces saturated with the adsorbates. Auger emission spectroscopy was used to monitor surface films. Results of the experiments indicate that friction and transfer characteristics are highly specific with respect to both the noble metal and surface film present. With all three metals and films transfer of the noble metal to iron occurred very rapidly. With all metals and films transfer of the noble metal to iron continuously increased with repeated passes except for silver and copper sliding on iron sulfide.

Buckley, D. H.

1979-01-01

273

Copper and iron concentrations in Ascophyllum nodosum (Fucales, Phaeophyta) from different sites in Ireland and after culture experiments in relation to thallus age and epiphytism  

Microsoft Academic Search

In laboratory experiments, copper concentrations in plants of Ascophyllum nodosum (L.) Le Jolis (Fucales, Phaeophyta) increased with the concentrations in the culture media and were highest in younger, meristematic thallus parts. After initial accumulation in high-copper medium and subsequent transfer to clean seawater for 5 days, no release of copper could be detected. Iron concentrations in A. nodosum tissue were

Dagmar B. Stengel; Matthew J. Dring

2000-01-01

274

The Proteome of Copper, Iron, Zinc, and Manganese Micronutrient Deficiency in Chlamydomonas reinhardtii*  

PubMed Central

Trace metals such as copper, iron, zinc, and manganese play important roles in several biochemical processes, including respiration and photosynthesis. Using a label-free, quantitative proteomics strategy (MSE), we examined the effect of deficiencies in these micronutrients on the soluble proteome of Chlamydomonas reinhardtii. We quantified >103 proteins with abundances within a dynamic range of 3 to 4 orders of magnitude and demonstrated statistically significant changes in ?200 proteins in each metal-deficient growth condition relative to nutrient-replete media. Through analysis of Pearson's coefficient, we also examined the correlation between protein abundance and transcript abundance (as determined via RNA-Seq analysis) and found moderate correlations under all nutritional states. Interestingly, in a subset of transcripts known to significantly change in abundance in metal-replete and metal-deficient conditions, the correlation to protein abundance is much stronger. Examples of new discoveries highlighted in this work include the accumulation of O2 labile, anaerobiosis-related enzymes (Hyd1, Pfr1, and Hcp2) in copper-deficient cells; co-variation of Cgl78/Ycf54 and coprogen oxidase; the loss of various stromal and lumenal photosynthesis-related proteins, including plastocyanin, in iron-limited cells; a large accumulation (from undetectable amounts to over 1,000 zmol/cell) of two COG0523 domain-containing proteins in zinc-deficient cells; and the preservation of photosynthesis proteins in manganese-deficient cells despite known losses in photosynthetic function in this condition.

Hsieh, Scott I.; Castruita, Madeli; Malasarn, Davin; Urzica, Eugen; Erde, Jonathan; Page, M. Dudley; Yamasaki, Hiroaki; Casero, David; Pellegrini, Matteo; Merchant, Sabeeha S.; Loo, Joseph A.

2013-01-01

275

The proteome of copper, iron, zinc, and manganese micronutrient deficiency in Chlamydomonas reinhardtii.  

PubMed

Trace metals such as copper, iron, zinc, and manganese play important roles in several biochemical processes, including respiration and photosynthesis. Using a label-free, quantitative proteomics strategy (MS(E)), we examined the effect of deficiencies in these micronutrients on the soluble proteome of Chlamydomonas reinhardtii. We quantified >10(3) proteins with abundances within a dynamic range of 3 to 4 orders of magnitude and demonstrated statistically significant changes in ~200 proteins in each metal-deficient growth condition relative to nutrient-replete media. Through analysis of Pearson's coefficient, we also examined the correlation between protein abundance and transcript abundance (as determined via RNA-Seq analysis) and found moderate correlations under all nutritional states. Interestingly, in a subset of transcripts known to significantly change in abundance in metal-replete and metal-deficient conditions, the correlation to protein abundance is much stronger. Examples of new discoveries highlighted in this work include the accumulation of O(2) labile, anaerobiosis-related enzymes (Hyd1, Pfr1, and Hcp2) in copper-deficient cells; co-variation of Cgl78/Ycf54 and coprogen oxidase; the loss of various stromal and lumenal photosynthesis-related proteins, including plastocyanin, in iron-limited cells; a large accumulation (from undetectable amounts to over 1,000 zmol/cell) of two COG0523 domain-containing proteins in zinc-deficient cells; and the preservation of photosynthesis proteins in manganese-deficient cells despite known losses in photosynthetic function in this condition. PMID:23065468

Hsieh, Scott I; Castruita, Madeli; Malasarn, Davin; Urzica, Eugen; Erde, Jonathan; Page, M Dudley; Yamasaki, Hiroaki; Casero, David; Pellegrini, Matteo; Merchant, Sabeeha S; Loo, Joseph A

2013-01-01

276

Synergetic effects of mixed copper-iron oxides oxygen carriers in chemical looping combustion  

SciTech Connect

Chemical looping combustion (CLC) is an emerging technology for clean energy production from fuels. CLC produces sequestration-ready CO{sub 2}-streams without a significant energy penalty. Development of efficient oxygen carriers is essential to successfully operate a CLC system. Copper and iron oxides are promising candidates for CLC. Copper oxide possesses high reactivity but it has issues with particle agglomeration due to its low melting point. Even though iron oxide is an inexpensive oxygen carrier it has a slower reactivity. In this study, mixed metal oxide carriers containing iron and copper oxides were evaluated for coal and methane CLC. The components of CuO and Fe{sub 2}O{sub 3} were optimized to obtain good reactivity while maintaining physical and chemical stability during cyclic reactions for methane-CLC and solid-fuel CLC. Compared with single metal oxygen carriers, the optimized Cu–Fe mixed oxide oxygen carriers demonstrated high reaction rate, better combustion conversion, greater oxygen usage and improved physical stability. Thermodynamic calculations, XRD, TGA, flow reactor studies and TPR experiments suggested that there is a strong interaction between CuO and Fe{sub 2}O{sub 3} contributing to a synergistic effect during CLC reactions. The amount of oxygen release of the mixed oxide carrier in the absence of a fuel was similar to that of the single metal oxides. However, in the presence of fuels, the oxygen consumption and the reaction profiles of the mixed oxide carriers were significantly better than that of the single metal oxides. The nature of the fuel not only influenced the reactivity, but also the final reduction status of the oxygen carriers during chemical looping combustion. Cu oxide of the mixed oxide was fully reduced metallic copper with both coal and methane. Fe oxide of the mixed oxide was fully reduced Fe metal with methane but it was reduced to only FeO with coal. Possible mechanisms of how the presence of CuO enhances the reduction of Fe{sub 2}O{sub 3} are discussed.

Siriwardane, Ranjani; Tian, Hanjing; Simonyi, Thomas; Poston, James

2013-06-01

277

Unique tetranuclear copper(II) cluster and monomeric iron(II), (III) complexes with a tris(imidazolyl) chelating ligand  

Microsoft Academic Search

Copper(II) and iron(II, III) complexes of the tripodal ligand, tris(1-methyl-1H-imidazol-2-yl)methanol (Htmim), have been synthesized and characterized by elemental analysis, 1H NMR and IR spectroscopies, magnetic moment measurement and X-ray crystallography. The structure of the copper complex, [Cu4(tmim)4(CF3SO3)2](CF3SO3)2·2MeOH (1), can be regarded as a polyimidazole-linked tetranuclear cluster where each copper atom adopts a five-coordinate square-pyramidal geometry ligated by the tmim anion.

Liang Ping Wu; Yoshiro Yamagiwa; Ichirou Ino; Kunihisa Sugimoto; Takayoshi Kuroda-Sowa; Tadao Kamikawa; Megumu Munakata

1999-01-01

278

The chemical speciation of dissolved nickel, copper, vanadium and iron in Liverpool Bay, Irish Sea  

NASA Astrophysics Data System (ADS)

CSV (cathodic stripping voltammetry) was used to determine dissolved nickel, copper, vanadium and iron in seawater samples collected from Liverpool Bay (Irish Sea). It is shown that the concentrations of the free metal ion and of the metal organic complexes can be calculated from the CSV-labile and total dissolved metal concentrations. The labile fraction consists of the inorganically complexed metal ions, and a certain proportion of the natural organic-metal complexes which depends on the relative stability of the metal complexes formed with the added chelator and with the natural organic ligands. Total dissolved metal concentrations were obtained after UV-photolysis of acidified samples. Results from two surveys, carried out during May and September 1985, clearly identified the River Mersey as being a significant contributor of both nickel and copper to Liverpool Bay. The dumping of sewage sludge produced elevated localized concentrations for colloidal nickel. Considerable proportions of nickel (31-41%) were found to occur as stable organic compounds, whereas almost all copper (98-99%) occurred in less stable organic complexes. A smaller proportion of iron (18%) was found to be bound by dissolved organic material. Organic complexation was generally greater in September than in May, which is illustrated by the mean log ?CuL values being higher in September (2·72) than in May (2·39). The absence of a relationship between organic complexation and the concentration of organic fluorescent material suggests that this material is not a major component of the organic metal complexing material in shelf waters.

Nimmo, M.; van den Berg, C. M. G.; Brown, J.

1989-07-01

279

Partitioning and distribution of dissolved copper, cadmium and organic matter in Mediterranean marine coastal areas: The case of a mucilage event  

NASA Astrophysics Data System (ADS)

Dissolved copper and cadmium partitioning and their interaction with organic matter were investigated in shallow coastal areas of the Aegean Sea (Eastern Mediterranean). The percentage of DGT-labile copper as for total dissolved copper ranged from 13 to 34% during summer and from 23 to 36% during winter, whereas the corresponding percentage for DGT-labile cadmium was higher in summer (38-68%), in comparison to winter (29-44%). The CCu was found to be 100-260 nM during summer while in winter the range was 42-430 nM. The corresponding CCd reached 27 and 45 nM, respectively. The mean TEP value in summer was high (208 ?g/L xanthan equiv.), while in winter it reached 441 ?g/L xanthan equiv., which indicates significant phytoplankton activity in winter, a feature occasionally observed in the stratified study areas after the breaking down of the thermocline/pycnocline, followed by consequent nutrient enrichment of the surface layers by nutrients accumulated in the sea bottom. A significant fraction of dissolved organic carbon (DOC) exhibited surface active properties and was determined as surface active substances (SAS) in mg/L eq. of nonionic surfactant Triton-X-100. Carbohydrates were also determined and they represented up to 33% of the DOC.

Scoullos, Michael; Plavši?, Marta; Karavoltsos, Sotiris; Sakellari, Aikaterini

2006-04-01

280

THE DETERMINATION OF ALUMINUM, IRON, AND SILICON IN SILVER-CADMIUM-INDIUM ALLOYS  

Microsoft Academic Search

Aluminum, iron, and silicon were determined by standard procedures with ; the modifications required by the nature of the matrix material. Aluminum and ; iron were determined colorimetrically wiih 8-quinolinol and orthophenanthrolene, ; reapectively, after appropriate separations. Silicon was determined ; gravimetrically. The methods have been tested on synthetic samples of known ; corposition and found to give acceptable results.

Ciaranello

1959-01-01

281

Association of serum levels of iron, copper, and zinc, and inflammatory markers with bacteriological sputum conversion during tuberculosis treatment.  

PubMed

Iron, copper, and zinc are key micronutrients that play an important role in the immune response to Mycobacterium tuberculosis. The present study aimed to evaluate the association between serum levels of those micronutrients, inflammatory markers, and the smear and culture conversion of M. tuberculosis during 60 days of tuberculosis treatment. Seventy-five male patients with pulmonary tuberculosis (mean age, 40.0?±?10.7 years) were evaluated at baseline and again at 30 and 60 days of tuberculosis treatment. Serum levels of iron, copper, zinc, albumin, globulin, C-reactive protein, and hemoglobin, and smear and cultures for M. tuberculosis in sputum samples were analyzed. Compared to healthy subjects, at baseline, patients with PTB had lower serum iron levels, higher copper levels and copper/zinc ratio, and similar zinc levels. During the tuberculosis treatment, no significant changes in the serum levels of iron, zinc, and copper/zinc were observed. Lower serum copper levels were associated with bacteriological conversion in tuberculosis treatment (tuberculosis-negative) at 30 days but not at 60 days (tuberculosis-positive). C-reactive protein levels and the C-reactive protein/albumin ratio were lower in tuberculosis-negative patients than in tuberculosis-positive patients at 30 and 60 days after treatment. Albumin and hemoglobin levels and the albumin/globulin ratio in patients with pulmonary tuberculosis increased during the study period, regardless of the bacteriological results. High serum globulin levels did not change among pulmonary tuberculosis patients during the study. Serum copper levels and the C-reactive protein/albumin ratio may be important parameters to evaluate the persistence of non-conversion after 60 days of tuberculosis treatment, and they may serve as predictors for relapse after successful treatment. PMID:24958018

Moraes, Milena Lima de; Ramalho, Daniela Maria de Paula; Delogo, Karina Neves; Miranda, Pryscila Fernandes Campino; Mesquita, Eliene Denites Duarte; de Melo Guedes de Oliveira, Hedi Marinho; Netto, Antônio Ruffino; Dos Anjos, Marcelino José; Kritski, Afrânio Lineu; de Oliveira, Martha Maria

2014-08-01

282

Comparative study of serum zinc, copper, manganese, and iron in preeclamptic pregnant women.  

PubMed

Preeclampsia complicates 2-8 % of all pregnancies and it is one of the leading causes of maternal mortality and pre-term delivery in the world. Unfortunately, there is scarcity of document discussing the circulating level of several essential trace elements in preeclampsia patients in Bangladesh. The present study was designed to evaluate the serum concentration of four trace elements, namely zinc, copper, manganese, and iron, in preeclamptic pregnant women. The study was conducted as a case-control study with 50 preeclamptic pregnant women as cases and 58 normotensive pregnant women as controls. Obstetric, anthropometric, and clinical data were collected at routine obstetric visits. Serum trace elements were determined by flame atomic absorption spectroscopy. Independent sample t test and Pearson's correlation test were done for the statistical analysis using the statistical software package SPSS, version 16.0 (SPSS Inc., Chicago, IL). We observed significant differences for gestational age, body mass index, and systolic and diastolic blood pressure between patient and control groups (p??0.05) except the correlation between zinc and iron in preeclampsia patients (p?copper, manganese, and iron compared to the healthy pregnant women. PMID:23749478

Sarwar, Md Shahid; Ahmed, Salma; Ullah, Mohd Shahid; Kabir, Humayun; Rahman, G K M Mustafizur; Hasnat, Abul; Islam, Mohammad Safiqul

2013-07-01

283

Assessment of cadmium and iron adsorption in sediment, employing a flow injection analysis system with on line filtration and detection by flame atomic absorption spectrometry and thermospray flame furnace atomic absorption spectrometry.  

PubMed

This work presents an evaluation of iron and cadmium adsorption in sediment of the Furnas Hydroelectric Plant Reservatory located in Alfenas, Minas Gerais (Brazil). The metal determination was done employing a flow injection analysis (FIA) with an on-line filtering system. As detection techniques, flame atomic absorption spectrometry (FAAS) for iron and thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) for cadmium determinations were used. The developed methodology presented good limits of detection, being 190 ?g L(-1) for iron and 1.36 ?g L(-1) for cadmium, and high sampling frequency for both metals 144 and 60 readings h(-1) for iron and cadmium, respectively. Both metals obey the Langmuir model, with maximum adsorptive capacity of 0?169 mg g(-1) for iron and 7?991 mg g(-1) for cadmium. For iron, a pseudo-first-order kinetic model was obtained with a theoretical Q(e)=9?8355 mg g(-1) (experimental Q(e)=9?5432 mg g(-1)), while for cadmium, a pseudo-second-order kinetic model was obtained, with a theoretical Q(e)=0.3123 mg g(-1) (experimental Q(e)=0?3052 mg g(-1)). PMID:24418136

de Oliveira, Fagner Moreira; Marchioni, Camila; Barros, Juan A V de A; do Lago, Ayla Campos; Wisniewski, Célio; Luccas, Pedro Orival

2014-01-27

284

Determination of iron, copper, manganese, zinc, lead, and cadmium in mushroom samples from Tokat, Turkey  

Microsoft Academic Search

Contents of Fe, Cu, Mn, Zn, Pb, and Cd in 10 mushrooms species from Tokat, Turkey were determined by atomic absorption spectrometry. The results indicate that Fe, Cu, Mn, and Pb levels in the species Fomes fementarius were the highest with means of 3904±307 mg\\/kg, 54±4 mg\\/kg, 64±5 mg\\/kg, 2.7±2.0 mg\\/kg, respectively. The highest level of Zn was 122±11 mg\\/kg

Ibrahim Turkekul; Mahfuz Elmastas; Mustafa Tüzen

2004-01-01

285

Effect of complexing ligands on the surface adsorption, internalization, and bioresponse of copper and cadmium in a soil bacterium, Pseudomonas putida.  

PubMed

Environmental quality criteria for metals toxic to soil and water organisms, using the free ion activity model or the biotic ligand model, are based on the concept that the major form of the metal available to the organism is the free metal ion, yet various metal complexes are bioavailable to a variety of soil and water organisms. We test here whether neutral copper or cadmium sulfates, negatively-charged copper or cadmium citrates and positively-charged copper acetate and cadmium chloride are bioavailable to a soil bacterium, Pseudomonas putida. Adsorption onto the cell surface and uptake into the periplasm and cytoplasm of this Gram-negative root colonizing bacterium was studied by adding a single concentration of Cu or Cd and varying the concentration of the ligands to complex 10-100% of the metal. Metal association from the complexes on and within the cell was defined using selective extraction procedures and compared with free ion controls using the Langmuir isotherm. Cellular responses also were assessed using a P. putida biosensor. Both uptake and bioresponse methodologies showed that P. putida was sensitive to the metal complexes. In particular, the bioresponse to Cu and Cd supplied as a citrate complex occurred with activities of free metal ions two orders of magnitude lower than for the control. We concluded that the tested metal complexes for Cu and Cd are taken up into the cell, where they trigger a bioresponse. We also discuss the implications of these findings on interactions between soil and water organisms and nanoparticles that release metal ions. PMID:23270705

McLean, Joan E; Pabst, Mindy W; Miller, Charles D; Dimkpa, Christian O; Anderson, Anne J

2013-04-01

286

Effect of complexans (EDTA, NTA and DTPA) on the exposure to high concentrations of cadmium, copper, zinc and lead  

SciTech Connect

The effects of complexans on the toxicity of short exposures to high chemical concentrations of heavy meals were examined. The heavy metals used were cadmium, zinc, lead and copper. Mortality every 24-h and the content of metal in each of three areas of fish - viscera, gills and other parts - were detemined both in the groups kept in water containing metal alone and in those whose aqueous environments contained complexan in mole concentrations three time that of the heavy metal. The carp (Cyprinus carpio L.) 8.0 + 0.5 cm were kept in groups of 8 to 10. There were altogether 49 such groups: 12 kept in three relatively high concentrations of each of the metals, Cu, Cd, Pb and Zn, alone; 36 groups in environments each containing only one of the three complexans, the tetrasodium salt of ethylene-diamine tetraacetic acid (EDTA), the trisodium salt of nitrilotriacetic acid (NTA), and the pentasodium salt of diethylenetriamine pentaacetic acid (DTPA) were used. Results indicate that the addition of the complexans resulted in the decrease of the tissue concentrations of Cd, Zn, Pb and Cu. It is considered that the heavy metals were not present merely as metal ions but formed complexes with the complexans, since the complexans were added at three times mole of the metal and therefore complex formation occurred in preference to the binding of the metals with the tissue proteins of the fish. It is furthermore assumed that the heavy metals can pass through the fish as metal-complexes, and so are not retained.

Muramoto, S.

1980-12-01

287

Subcellular accumulation of different concentrations of cadmium, nickel, and copper in Indian mustard and application of a sigmoidal model.  

PubMed

Certain plant species can tolerate and even detoxify metallic elements. This detoxification ability has been shown to depend on how plants distribute the metallic elements in their tissues. In turn, this distribution may have an important impact on phytoremediation. Here, we investigated the effects of different single-metal concentrations (10, 50, 100, and 300 ?mol L) of cadmium (Cd), nickel (Ni), and copper (Cu) on their subcellular distribution in L. var. (Indian mustard). At the applied concentration of 300 ?mol L, 98% of the Cu and 79% of Cd were retained in the roots, while Ni was distributed between leaves (32%), stems (29%), and roots (39%). The cell wall and soluble fractions were the dominant storage compartments for Cd and Cu in the stems and leaves, whereas the soluble fraction was the dominant storage compartment for Ni in stems and leaves. Scanning electron microscopy (SEM) X-ray micrographs showed a breakdown of epidermal, palisade, and spongy parenchyma cells following the 300 ?mol L Cd, Ni, and Cu treatment. A sigmoidal model is a powerful tool to describe the subcellular accumulation and tissue concentrations of Cd, Ni, and Cu following exposure to various concentrations of metals. The coefficients of determination () values for the description of the accumulation were high, although the membrane subcellular fraction did not fit the equation. Both the maximum accumulation capacity and the critical concentrations of metals were well described by the model. The results indicate that the use of a sigmoidal model is a promising method that could improve the understanding of metal accumulation at the subcellular level in Indian mustard. PMID:24216365

Wang, Yuanpeng; Huang, Jing; Gao, Yanzheng

2013-07-01

288

Liver and kidney concentrations of strontium, barium, cadmium, copper, zinc, manganese, chromium, antimony, selenium and lead in cats  

PubMed Central

Background In order to provide new knowledge on the storage of strontium (Sr), barium (Ba), cadmium (Cd), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), antimony (Sb), selenium (Se) and lead (Pb) in the feline organism, we measured the concentrations of these elements in the liver, renal cortex and renal medulla, evaluating also the impact of age, sex or the occurrence of a chronic kidney disease (CKD). The element concentrations in the tissues of 47 cats (22 male; 25 female; aged between 2 months and 18 years) were measured using inductively coupled plasma mass spectrometry. Results Cu, Zn and Mn were the highest in the liver, followed by the renal cortex and the renal medulla. The Cd concentrations were lower in the renal medulla compared to the renal cortex and the liver, and Sr was higher in the renal medulla compared to the liver. The Se concentrations in the cortex of the kidneys were higher than in the medulla of the kidneys and in the liver. Higher Cd concentrations were measured in the renal cortex of female cats, while no further gender-related differences were observed. Except for Cr, Sb and Se, age-dependencies were detected for the storage of all elements. The occurrence of a CKD also affected the storage of the elements, with lower concentrations of Ba (renal medulla), Zn (renal cortex; renal medulla) and Mn (liver; renal medulla), but higher Cd concentrations (liver; renal cortex) in diseased cats. Conclusions In conclusion, the present results provide new information on the accumulation of specific elements in the feline liver and kidneys, demonstrating a dependency on age and an impaired kidney function, but not on the sex of the animals.

2014-01-01

289

Seasonal variation in copper, zinc, chromium, lead and cadmium levels in hepatopancreas, gill and muscle tissues of the mussel Brachidontes pharaonis Fischer, collected along the Mersin coast, Turkey.  

PubMed

Levels of copper, zinc, cadmium, chromium and lead were determined in the gill, hepatopancreas and muscle tissues of Brachidontes pharaonis collected from the Mersin coasts of Turkey. Water and animal samples were collected monthly from the four stations between June 2002 and May 2003 for metal determinations. Metal levels in water samples of Mersin coasts were higher than those measured in other parts of Turkish coasts. Levels of metals in soft tissues of B. pharaonis showed an increase towards autumn and winter months which exceeded the levels that are recommended by Turkish Standart Institute's food codex. PMID:17657395

Karayakar, Fahri; Erdem, Cahit; Cicik, Bedii

2007-09-01

290

Application of cooperative iron/copper catalysis to a palladium-free borylation of aryl bromides with pinacolborane.  

PubMed

A new cooperative copper/iron catalysis for the borylation of various aryl bromides with pinacolborane, at -10 °C, is reported. Use of the toxic, precious metal Pd is avoided. The mechanism of the protodebromination side reaction is discussed. PMID:24738740

Labre, Flavien; Gimbert, Yves; Bannwarth, Pierre; Olivero, Sandra; Duñach, Elisabet; Chavant, Pierre Y

2014-05-01

291

Solid-phase extraction of copper, iron and zinc ions on Bacillus thuringiensis israelensis loaded on Dowex optipore V-493.  

PubMed

Bacillus thuringiensis israelensis loaded on Dowex optipore V-493 as new adsorbent for the separation-preconcentration of heavy metal ions has been proposed. The analytical conditions for the quantitative recoveries of copper(II), iron(III) and zinc(II) including pH, amounts of adsorbent, sample volume, etc. were investigated. The influences of alkaline and earth alkaline ions were also reported. The recovery values for the analytes are generally higher than 95%. The preconcentration factor was 37. The limit of detections of the analyte ions (k=3, N=21) were 1.14 microgL(-1) for copper, 2.01 microgL(-1) for iron and 0.14 microgL(-1) for zinc. The relative standard deviations of the determinations were found to be lower than 9%. The procedure was validated by analyzing copper, iron and zinc contents in two certified reference materials, NRCC-SLRS-4 Riverine water and NIST SRM 1515 Apple leaves. Agreements between the obtained results and the certified values were achieved. The developed preconcentration method was applied in the flame atomic absorption spectrometric determination of copper, iron and zinc in several samples including a multivitamin-multimineral tablet, dialysis solutions, natural waters and some food samples. PMID:18359563

Tuzen, Mustafa; Melek, Esra; Soylak, Mustafa

2008-11-30

292

Chelating of iron and copper alters properties of DNA in L5178Y cells, as revealed by the comet assay.  

PubMed

We have previously found different proportions of iron and copper in nuclei of two sublines of murine lymphoma L5178Y (LY) and proposed a model of chromatin organization with these metal ions at the DNA attachment sites. We now examine the effect of chelators, desferal (DFO, iron-specific) and neocupreine (NEO, copper-specific) on DNA of LY-R and LY-S cells, using the comet and micronuclei frequency tests. There is less copper and more iron in LY-R nuclei than in LY-S nuclei. Accordingly, the effect of NEO is more marked in LY-R than in LY-S cells and in both sublines it is expressed as enhanced tail moment (measure of DNA damage in the comet assay) and increased micronuclei frequency. On the contrary, the effect of DFO on the tail moment is less pronounced in LY-R than in LY-S cells. With increasing DFO concentrations, there is a gradual decrease in the tail moment values below the control level in LY-S cells. In LY-R cells the tail moment values initially increase, then gradually decrease, eventually falling below the control level. This points to a dramatic conformational change that masks the effect of DNA discontinuities. The presence of the latter is indicated by the increase in micronuclei frequency. These results support the postulated differential role of iron and copper ions in maintaining the higher order DNA structure in LY sublines. PMID:10377948

Kruszewski, M; Iwane?ko, T; Bouzyk, E; Szumiel, I

1999-05-14

293

Structure of self-interstitial atom clusters in iron and copper  

NASA Astrophysics Data System (ADS)

The dislocation core structure of self-interstitial atom (SIA) clusters in bcc iron and fcc copper is determined using the hybrid ab initio continuum method of Banerjee [Philos. Mag. 87, 4131 (2007)]. To reduce reliance on empirical potentials and to facilitate predictions of the effects of local chemistry and stress on the structure of defects, we present here a hybrid extension of the Peierls-Nabarro continuum model, with lattice resistance to slip determined separately from ab initio calculations. A method is developed to reconstruct atomic arrangements and geometry of SIA clusters from the hybrid model. The results are shown to compare well with molecular-dynamics simulations. In iron, the core structure does not show dependence on the size of the self-interstitial cluster, and is nearly identical to that of a straight edge dislocation. However, the core structure of SIA clusters in Cu is shown to depend strongly on the cluster size. Small SIA clusters are found to have nondissociated compact dislocation cores, with a strong merging of Shockley partial dislocations and a relatively narrow stacking fault (SF) region. The compact nature of the SIA core in copper is attributed to the strong dependence of the self-energy on the cluster size. As the number of atoms in the SIA cluster increases, Shockley partial dislocations separate and the SF region widens, rendering the SIA core structure to that of an edge dislocation. The separation distance between the two partials widens as the cluster size increases, and tends to the value of a straight edge dislocation for cluster sizes above 400 atoms. The local stress is found to have a significant effect on the atomic arrangements within SIA clusters in copper and the width of the stacking faults. An applied external shear can delocalize the core of an SIA cluster in copper, with positive shear defined to be on the (111) plane along the [1¯1¯2] direction. For an SIA cluster containing 1600 atoms, a positive 1 GPa shear stress delocalizes the cluster and expands the SF to 30b , while a negative shear stress of 2 GPa contracts the core to less than 5b , where b is the Burgers vector magnitude.

Takahashi, Akiyuki; Ghoniem, Nasr M.

2009-11-01

294

No significant effect of iron deficiency on cadmium body burden or kidney dysfunction among women in the general population in Japan  

Microsoft Academic Search

Objective. To examine if iron-deficient conditions modify body burden or health effects of cadmium among women in the general population in Japan.Methods. In 2002, 1,482 women aged 20 to 74 years in six prefectures in Japan provided informed consent to participate in this study. They offered peripheral blood and spot urine samples, and answered questionnaires on their social habits and

T. Tsukahara; T. Ezaki; J. Moriguchi; K. Furuki; Y. Fukui; H. Ukai; S. Okamoto; H. Sakurai; M. Ikeda

2003-01-01

295

Development of copper sulfide/cadmium sulfide thin-film solar cells  

SciTech Connect

The purpose of this work has been to identify aspects of cell fabrication and treatment which are critical for achieving high efficiency Cu/sub 2/S/CdS solar cells. In approaching the problem several comparisons were made of the effects of specific steps in two methods of cell fabrication. These methods had previously given cells of about 6% and a maximum of 9% efficiency. Three areas requiring special attention and specific means to achieve acceptable results were identified. (1) The Cu/sub 2/S/CdS heterojunction area must be minimized. If single source evaporations of CdS are made on substrates whose temperatures (approx. 220/sup 0/C) are monitored and controlled using welded thermocouples, the CdS films will have adequately large grains (grain diameter greater than or equal to 2 ..mu..m) and will not develop significant etch pits during texturing in a mild etchant solution. (2) The termination of the wet barrier processing steps must be done carefully. An acceptable termination involves minimizing the amount of cuprous chloride retained on the cell surface during transfer to a rinsing stage while providing adequate exclusion of air from the space above the surface of the cuprous chloride solution. (3) Once formed, the Cu/sub 2/S layer should not be exposed to high temperatures (>100/sup 0/C) for long periods of time (> 5 min) if surface adsorbed moisture or oxygen are present. Heat treatments in ampoules under flowing hydrogen atmospheres should be preceded and followed by periods of at least 30 minutes at room temperature in the reducing ambient. If all these precautions are taken, wet chemical barrier processing of thermally evaporated CdS films on zinc-plated copper foil substrates yields cells of nearly 8% conversion efficiency without AR coating.

Szedon, J.R.; Biter, W.J.; Abel, J.A.; Dickey, H.C.; Shirland, F.A.

1981-02-27

296

ESR of copper and iron complexes with antitumor and cytotoxic properties.  

PubMed Central

The relatively few iron and copper metal complexes which have been examined in cells and tissues for their redox properties, radical generation properties, and antitumor activity are discussed for studies which utilized electron spin resonance spectroscopy (ESR). A common property of a number of metal complexes, which include bleomycin, adriamycin, and thiosemicarbazones described in this review, is that they are readily reduced by thiol compounds and oxidized by oxygen or reduced species of oxygen to produce radicals. Structural features of these reactions are identified by ESR spectroscopy in model systems and often in cells. Furthermore, ESR spectroscopy has been most useful to probe the environment of the complexes in cells and to measure the rate of reduction of their oxidized forms. As a result of these studies, it is anticipated that more attention will be given to the exploration of redox-active metal complexes as drugs.

Antholine, W E; Kalyanaraman, B; Petering, D H

1985-01-01

297

ESR of copper and iron complexes with antitumor and cytotoxic properties  

SciTech Connect

The relatively few iron and copper metal complexes which have been examined in cells and tissues for their redox properties, radical generation properties, and antitumor activity are discussed for studies which utilized electron spin resonance spectroscopy (ESR). A common property of a number of metal complexes, which include bleomycin, adriamycin, and thiosemicarbazones described in this review, is that they are readily reduced by thiol compounds and oxidized by oxygen or reduced species of oxygen to produce radicals. Structural features of these reactions are identified by ESR spectroscopy in model systems and often in cells. Furthermore, ESR spectroscopy has been most useful to probe the environment of the complexes in cells and to measure the rate of reduction of their oxidized forms. As a result of these studies, it is anticipated that more attention will be given to the exploration of redox-active metal complexes as drugs. 95 references.

Antholine, W.E.; Kalyanaraman, B.; Petering, D.H.

1985-12-01

298

Electronic band structure and optical absorption of nanotubular zinc oxide doped with Iron, Cobalt, or Copper  

NASA Astrophysics Data System (ADS)

The absorption spectra of the precursor-derived solid solutions Zn1 - x M x O ( M = Fe, Co, Cu) with a tubular morphology of aggregates have been investigated in the ultraviolet and visible regions. The maximum metal concentration x in the Zn1 - x M x O solid solutions is 0.075 for iron, 0.2 for cobalt, and 0.1 for copper. It has been found that the optical absorption and the band gap of the Zn1 - x M x O compounds depend on the type of dopant. The obtained experimental data have been interpreted using the results of the performed ab initio calculations of the electronic band structure and optical absorption.

Zhukov, V. P.; Krasil'nikov, V. N.; Perelyaeva, L. A.; Baklanova, I. V.; Shein, I. R.

2013-12-01

299

Structure and properties of clusters of self-interstitial atoms in fcc copper and bcc iron  

NASA Astrophysics Data System (ADS)

Static and molecular dynamics simulations have been used with different types of interatomic potentials to investigate the structure, properties and stability of self-interstitial atom (SIA) clusters produced during irradiation. In f-iron (Fe), faulted clusters of <110> dumbbells are unstable for all the potentials. The most stable SIA clusters are sets of parallel <111> crowdions. Large clusters of this type form perfect dislocation loops with Burgers vector b = ½<111>. Small clusters (less than 9 SIAs) of <100> crowdions are stable at 0 K, but transform into a set of <111> crowdions on annealing. Larger <100> clusters are stable and form perfect dislocation loops with b = <100>. Both types of loops are glissile. In copper (Cu), clusters of parallel <100> dumbbells and <110> crowdions are stable. Large clusters of these types form faulted and perfect dislocation loops with b = 1/3<111> and ½<110> respectively. Small faulted clusters (less than 7 SIAs) of irregular shape can transform into a set of <110> crowdions during annealing. Larger faulted clusters are stable as hexagonal 1/3<111> Frank loops at temperatures of about up to 1050 K for a period of several hundred picoseconds. All faulted clusters are sessile. Clusters of <110> crowdions and ½<110> perfect loops are glissile and stable at all temperatures. When large enough (more than 49-64 SIAs) they can dissociate on their glide prism. Symmetric three-dimensional clusters of <100> dumbbells are stable at 0 K but during annealing they transform into sets of <110> crowdions. The results for both iron and copper are discussed and compared with experimental data and provide a basis for investigating and explaining the observed differences in radiation damage accumulation behaviour between fcc and bcc metals.

Osetsky, Yu. N.; Serra, A.; Singh, B. N.; Golubov, S. I.

2000-09-01

300

Three histidine residues of amyloid-beta peptide control the redox activity of copper and iron.  

PubMed

Zinc, iron and copper are concentrated in senile plaques of Alzheimer disease. Copper and iron catalyze the Fenton-Haber-Weiss reaction, which likely contributes to oxidative stress in neuronal cells. In this study, we found that ascorbate oxidase activity and the intensity of ascorbate radicals measured using ESR spectroscopy, generated by free Cu(II), was decreased in the presence of amyloid-beta (Abeta), the major component of senile plaques. Specifically, the ascorbate oxidase activity was strongly inhibited (85% decrease) in the presence of Abeta1-16 or Abeta1-42, whereas it was only slightly inhibited in the presence of Abeta1-12 or Abeta25-35 (<20% inhibition). Ascorbate-dependent hydroxyl radical generation by free Cu(II) decreased in the presence of Abeta in the identical order of Abeta1-42, Abeta1-16 > Abeta1-12 and was abolished in the presence of 2-fold molar excess glycylhystidyllysine (GHK). Ascorbate oxidase activity and ascorbate-dependent hydroxyl radical generation by free Fe(III) were inhibited by Abeta1-42, Abeta1-16, and Abeta1-12. Although Cu(II)-Abeta shows a significant SOD-like activity, the rate constant for the reaction of superoxide with Cu(II)-Abeta was much slower than that with SOD. Overall, our results suggest that His6, His13, and His14 residues of Abeta1-42 control the redox activity of transition metals present in senile plaques. PMID:17929832

Nakamura, M; Shishido, N; Nunomura, Akihiko; Smith, Mark A; Perry, George; Hayashi, Y; Nakayama, K; Hayashi, T

2007-11-01

301

COPPER  

EPA Science Inventory

The report is a review of current knowledge of the distribution of copper in the environment and living things. Metabolism and the effects of copper in the biosphere are also considered. Copper compounds are common and widely distributed in nature. They are also extensively mined...

302

Regulation of Brain Iron and Copper Homeostasis by Brain Barrier Systems: Implication in Neurodegenerative Diseases  

PubMed Central

Iron (Fe) and copper (Cu) are essential to neuronal function; excess or deficiency of either is known to underlie the pathoetiology of several commonly known neurodegenerative disorders. This delicate balance of Fe and Cu in the central milieu is maintained by the brain barrier systems, i.e., the blood-brain barrier (BBB) between the blood and brain interstitial fluid and the blood- cerebrospinal fluid barrier (BCB) between the blood and cerebrospinal fluid (CSF). This review provides a concise description on the structural and functional characteristics of the brain barrier systems. Current understanding of Fe and Cu transport across the brain barriers is thoroughly examined, with major focuses on whether the BBB and BCB coordinate the direction of Fe and Cu fluxes between the blood and brain/CSF. In particular, the mechanism by which pertinent metal transporters in the barriers, such as the transferrin receptor (TfR), divalent metal transporter (DMT1), copper transporter (CTR1), ATP7A/B, and ferroportin (FPN), regulate metal movement across the barriers is explored. Finally, the detrimental consequences of dysfunctional metal transport by brain barriers, as a result of endogenous disorders or exogenous insults, are discussed. Understanding the regulation of Fe and Cu homeostasis in the central nervous system aids in the design of new drugs targeted on the regulatory proteins at the brain barriers for the treatment of metal’s deficiency or overload-related neurological diseases.

Zheng, Wei; Monnot, Andrew D.

2011-01-01

303

Changes in Selenium, Copper, Cadmium, and Zinc Concentrations in Mullet ( Mugil cephalus ) from the Southern Basin of Lake Macquarie, Australia, in Response to Alteration of Coal-Fired Power Station Fly Ash Handling Procedures  

Microsoft Academic Search

Selenium, copper, cadmium, and zinc concentrations were measured in mullet (Mugil cephalus) from the southern basin of Lake Macquarie, Australia, in 1997 to determine if improved ash-handling practices at an adjacent\\u000a coal fired power station, implemented in 1995, had significantly lowered trace metal concentrations in mullet tissues. Mean\\u000a muscle tissue concentrations of selenium (5.9 ± 0.7 ?g\\/g dry mass), copper

J. Kirby; W. Maher; D. Harasti

2001-01-01

304

Migration of iron, lead, cadmium and tin from tinplate-coated cans into chickpeas.  

PubMed

Migration studies of trace metals were carried out on coated chickpea cans marketed in Lebanon. Four elements--(Fe), tin (Sn), lead (Pb) and cadmium (Cd)--were analysed by atomic absorption spectrometry (AAS) after microwave digestion. Over 3 months, three different storage temperatures (5°C, room temperature and 40°C) were tested. In all cases, the migration of Fe reached a plateau after around 50 days of storage, while the migration of Pb was slow till 50 days, then it increased rapidly. Cd and Sn levels did not increase. Moreover, no effect of temperature was observed in the case of Fe, whereas Pb levels showed slower migration in cans stored at 5°C. Comparing cans from different chickpea brands (Lebanese and foreign) showed that the characteristics of the container have an effect on metal release. PMID:24059695

Kassouf, A; Chebib, H; Lebbos, N; Ouaini, R

2013-01-01

305

The Homeostasis of Iron, Copper, and Zinc in Paracoccidioides Brasiliensis, Cryptococcus Neoformans Var. Grubii, and Cryptococcus Gattii: A Comparative Analysis  

PubMed Central

Iron, copper, and zinc are essential for all living organisms. Moreover, the homeostasis of these metals is vital to microorganisms during pathogenic interactions with a host. Most pathogens have developed specific mechanisms for the uptake of micronutrients from their hosts in order to counteract the low availability of essential ions in infected tissues. We report here an analysis of genes potentially involved in iron, copper, and zinc uptake and homeostasis in the fungal pathogens Paracoccidioides brasiliensis, Cryptococcus neoformans var. grubii, and Cryptococcus gattii. Although prior studies have identified certain aspects of metal regulation in Cryptococcus species, little is known regarding the regulation of these elements in P. brasiliensis. We also present amino acid sequences analyses of deduced proteins in order to examine possible conserved domains. The genomic data reveals, for the first time, genes associated to iron, copper, and zinc assimilation and homeostasis in P. brasiliensis. Furthermore, analyses of the three fungal species identified homologs to genes associated with high-affinity uptake systems, vacuolar and mitochondrial iron storage, copper uptake and reduction, and zinc assimilation. However, homologs to genes involved in siderophore production were only found in P. brasiliensis. Interestingly, in silico analysis of the genomes of P. brasiliensis Pb01, Pb03, and Pb18 revealed significant differences in the presence and/or number of genes involved in metal homeostasis, such as in genes related to iron reduction and oxidation. The broad analyses of the genomes of P. brasiliensis, C. neoformans var. grubii, and C. gattii for genes involved in metal homeostasis provide important groundwork for numerous interesting future areas of investigation that are required in order to validate and explore the function of the identified genes and gene pathways.

Silva, Mirelle Garcia; Schrank, Augusto; Bailao, Elisa Flavia L.C.; Bailao, Alexandre Melo; Borges, Clayton Luiz; Staats, Charley Christian; Parente, Juliana Alves; Pereira, Maristela; Salem-Izacc, Silvia Maria; Mendes-Giannini, Maria Jose Soares; Oliveira, Rosely Maria Zancope; Silva, Livia Kmetzsch Rosa e; Nosanchuk, Joshua D.; Vainstein, Marilene Henning; de Almeida Soares, Celia Maria

2011-01-01

306

Expression profiling reveals functionally redundant multiple-copy genes related to zinc, iron and cadmium responses in Brassica rapa.  

PubMed

Genes underlying environmental adaptability tend to be over-retained in polyploid plant species. Zinc deficiency (ZnD) and iron deficiency (FeD), excess Zn (ZnE) and cadmium exposure (CdE) are major environmental problems for crop cultivation, but little is known about the differential expression of duplicated genes upon these stress conditions. Applying Tag-Seq technology to leaves of Brassica rapa grown under FeD, ZnD, ZnE or CdE conditions, with normal conditions as a control, we examined global gene expression changes and compared the expression patterns of multiple paralogs. We identified 812, 543, 331 and 447 differentially expressed genes under FeD, ZnD, ZnE and CdE conditions, respectively, in B. rapa leaves. Genes involved in regulatory networks centered on the transcription factors bHLH038 or bHLH100 were differentially expressed under (ZnE-induced) FeD. Further analysis revealed that genes associated with Zn, Fe and Cd responses tended to be over-retained in the B. rapa genome. Most of these multiple-copy genes showed the same direction of expression change under stress conditions. We conclude that the duplicated genes involved in trace element responses in B. rapa are functionally redundant, making the regulatory network more complex in B. rapa than in Arabidopsis thaliana. PMID:24738937

Li, Jimeng; Liu, Bo; Cheng, Feng; Wang, Xiaowu; Aarts, Mark G M; Wu, Jian

2014-07-01

307

Role of the copper-oxygen defect in cadmium telluride solar cells  

NASA Astrophysics Data System (ADS)

Thin-film CdTe is one of the leading materials used in photovoltaic (PV) solar cells. One way to improve device performance and stability is through understanding how various device processing steps alter defect states in the CdTe layer. Photoluminescence (PL) studies can be used to examine radiative defects in materials. This study uses low-temperature PL to probe the defects present in thin-film CdTe deposited for solar cells. One key defect seen in the thin-film CdTe was reproduced in single-crystal (sX) CdTe by systematic incorporation of known impurities in the thin-film growth process, hence demonstrating that both copper and oxygen were necessary for its formation. Polycrystalline (pX) thin-film glass/SnO2:F/CdS/CdTe structures were examined. The CdTe layer was grown via close-spaced sublimation (CSS), vapor transport deposition (VTD), and physical vapor deposition (PVD). After CdTe deposition, followed by a standard CdC12 treatment and a ZnTe:Cu back contact, a PL peak was seen at ˜1.46 eV from the free back surface of all samples (1.456 eV for CSS and PVD, 1.460-1.463 eV for VTD). However, before the Cu-containing contact was added, this peak was not seen from the front of the CdTe (the CdS/CdTe junction region) in any device with CdTe thickness greater than 4 mum. The CdCl2 treatment commonly used to increase CdTe grain size did not enhance or reduce the peak at ˜1.46 eV relative to the rest of the PL spectrum. When the Cu-containing contact was applied, the PL spectra from both the front and back of the CdTe exhibited the peak at 1.456 eV. The PL peak at ˜1.46 eV was present in thin-film CdTe after deposition, when the dominant impurities are expected to be both Cu from the CdTe source material and O introduced in the chamber during growth to assist in CdTe film density. Since Cu and/or O appeared to be involved in this defect, PL studies were done with sX CdTe to distinguish between the separate effects of Cu or O and the combined effect of Cu and O. Photoluminescence on the sX samples revealed a unique transition at 1.456 eV, identical to the one seen in CSS thin-film CdTe, only when both Cu and O were introduced simultaneously. Theoretical calculations indicate that this PL line is likely a transition between the valence band and a Cui-OTe donor complex 150 meV below the conduction band. Formation of a Cui-OT, donor complex was expected to limit the performance of the CdS/CdTe solar cell. However, this was difficult to observe in the prepared devices, likely because other beneficial processes occurred simultaneously, such as formation of CUCd acceptors in the CdTe layer and improvement in the quality of the back contact by including Cu. It was possible to see the theoretical effects of this defect using AMPS--1D numerical simulations. The simulated J-V curves indicated that a donor level 150 meV from the conduction band would reduce the Voc, hence reducing the overall device efficiency. Therefore, despite the lack of direct experimental evidence, it is very plausible that the CU i-OTe defect observed with photoluminescence may serve to limit the possible attainable efficiency in CdS/CdTe solar cells.

Corwine, Caroline R.

308

Effects of rutin supplementation on antioxidant status and iron, copper, and zinc contents in mouse liver and brain  

Microsoft Academic Search

The effect of rutin on total antioxidant status as well as on trace elements such as iron, copper, and zinc in mouse liver\\u000a and brain were studied. Mice were administrated with 0.75 g\\/kg or 2.25 g\\/kg P. O. of rutin for 30 d consecutively. Following\\u000a the treatment, the activity of total antioxidant status, catalase, Cu,Zn-superoxide dismutase, Mn-superoxide dismutase, zinc,\\u000a copper,

Zhonghong Gao; Huibi Xu; Kaixun Huang

2002-01-01

309

Effects of cadmium, copper, lead and zinc on growth, reproduction and survival of the earthworm Eisenia fetida (Savigny): Assessing the environmental impact of point-source metal contamination in terrestrial ecosystems  

Microsoft Academic Search

The earthworm Eisenia fetida (Annelida: Oligochaeta) was exposed to a geometric series of concentrations of cadmium, copper, lead and zinc in artificial soil using the OECD recommended protocol. Mortality, growth and cocoon production were measured over 56 days to deter- mine LCso and EC~ values. No observed effect concen- trations ( NOECs) were also estimated. Furthermore, the percentage of viable

D. J. Spurgeon; S. P. Hopkin; D. T. Jones

1994-01-01

310

Nutrient composition of selected wheats and wheat products. VI. Distribution of manganese, copper, nickel, zinc, magnesium, lead, tin, cadmium, chromium, and selenium as determined by atomic absorption spectroscopy and colorimetry  

Microsoft Academic Search

Magnesium and eight trace mineral elements, manganese, copper, nickel, zinc, lead, tin, cadmium, and chromium, were determined by atomic absorption spectroscopy in 11 known wheats or wheat blends, 20 commercially prepared flours from these wheats, and 25 specially prepared products from the flours. The same minerals were determined in ten consumer products from ten different cities. There was significant variation

E. G. Zook; F. E. Greene; E. R. Morris

1970-01-01

311

Novel erm(T)-Carrying Multiresistance Plasmids from Porcine and Human Isolates of Methicillin-Resistant Staphylococcus aureus ST398 That Also Harbor Cadmium and Copper Resistance Determinants  

PubMed Central

This study describes three novel erm(T)-carrying multiresistance plasmids that also harbor cadmium and copper resistance determinants. The plasmids, designated pUR1902, pUR2940, and pUR2941, were obtained from porcine and human methicillin-resistant Staphylococcus aureus (MRSA) of the clonal lineage ST398. In addition to the macrolide-lincosamide-streptogramin B (MLSB) resistance gene erm(T), all three plasmids also carry the tetracycline resistance gene tet(L). Furthermore, plasmid pUR2940 harbors the trimethoprim resistance gene dfrK and the MLSB resistance gene erm(C), while plasmids pUR1902 and pUR2941 possess the kanamycin/neomycin resistance gene aadD. Sequence analysis of approximately 18.1 kb of the erm(T)-flanking region from pUR1902, 20.0 kb from pUR2940, and 20.8 kb from pUR2941 revealed the presence of several copies of the recently described insertion sequence ISSau10, which is probably involved in the evolution of the respective plasmids. All plasmids carried a functional cadmium resistance operon with the genes cadD and cadX, in addition to the multicopper oxidase gene mco and the ATPase copper transport gene copA, which are involved in copper resistance. The comparative analysis of S. aureus RN4220 and the three S. aureus RN4220 transformants carrying plasmid pUR1902, pUR2940, or pUR2941 revealed an 8-fold increase in CdSO4 and a 2-fold increase in CuSO4 MICs. The emergence of multidrug resistance plasmids that also carry heavy metal resistance genes is alarming and requires further surveillance. The colocalization of antimicrobial resistance genes and genes that confer resistance to heavy metals may facilitate their persistence, coselection, and dissemination.

Gomez-Sanz, Elena; Kadlec, Kristina; Fessler, Andrea T.; Zarazaga, Myriam; Schwarz, Stefan

2013-01-01

312

Domain Wall Pinning in the Iron-Rich Iron-Gold and Iron-Copper Binary Alloys  

NASA Astrophysics Data System (ADS)

Specimens of alpha-phase (b.c.c.) solid-solutions of iron-rich FeAu (1.10 at % Au) and FeCu (1.07 at % Cu) were thermally aged at 700 ^circC for different time durations. Precipitation and growth of the secondary phase epsilon Au (f.c.c.) and epsilonCu (f.c.c.) took place in the FeAu and FeCu alloys respectively, during the heat treatment. The specimens were polished and then studied under a transmission electron microscope. The size, density and shape of the precipitates were determined for different aging conditions. The knowledge of these parameters are fitted to a recent theory of strong and weak domain wall pinning by a random array of inhomogeneities, which allows values of the coercive field H_ {c}, to be predicted. Critical comparison between the observed and the calculated coercive fields were then made. A pinning index beta^ ' was derived and used to characterize the pinning behavior of the specimens. When beta ^' is close to or larger than 1, the pinning is definitely strong, else the pinning is weak. Based on the strong and weak pinning models, the relationships between the a.c. susceptibility chi_{a.c.}, and the effective bias field H, are derived for ferromagnets with random inhomogeneities. It is found that when H is less than H_{c}, chi_{a.c.} remains independent of H. When H is larger than H_{c}, chi_{a.c.} is proportional to H^{-1/2} (or H ^{-3/7} if demagnetizing effect due to the unpaired spins on the surface of the bowed wall is considered) and H^{-1} for strong and weak pinning respectively. A phase-locked magnetometer was employed to measure the a.c. susceptibilities of the FeAu and FeCu specimens after different durations of aging, as a function of bias field. The data were refined and analysed under the light of the newly developed relationships. The pinning regime of the specimens were then determined. Expressions for the fluctuation field, S _{v}, (a function of the magnetic viscosity coefficient) for the pinning models were derived. The relationships between coercive field and the activation volume of the domain wall in the two pinning models were also deduced. The activation volume were calculated for each case and were put into the appropriate S_ {v} expression for the S_ {v} values to be determined. The results were studied and compared with the works done by Wohlfarth and Barbier. The results obtained from these investigations converge toward a single conclusion. The pinning regime in the as-quenched FeAu specimen (zero age) and the low -age FeCu specimens is weak. For the prolonged age specimens of FeAu and FeCu, strong pinning is active. This claim was verified by the electron microscopic studies of the magnetic features and microstructure in these specimens by using Lorentz microscopic techniques.

Ng, Dickon H. L.

1989-12-01

313

Use of 3-hydroxy-1,3-diphenyltriazine in the spectrophotometric determination of copper, palladium, iron, cobalt, nickel, and molybdenum.  

PubMed

3-Hydroxy-1,3-diphenyltriazine (HDPTA) forms brightly coloured complexes with copper, palladium, iron, cobalt and nickel ions, which are readily extractable in benzene. The deep yellow molybdenum complex is completely soluble in 60% ethanol. All the chelates have a definite absorption maximum between 398 and 422 nm, the reagent absorption being negligible above 415 nm. The molar composition of the chelates is ML(2), except for iron and cobalt which form ML(3) complexes. Microquantities of these metals can be determined spectrophotometrically with HDPTA. PMID:18960697

Das, B; Shome, S C

1970-01-01

314

Self-organization of iron-atom nanostructures in the first layer of the (100) copper surface  

NASA Astrophysics Data System (ADS)

Mechanisms of the diffusion of surface vacancies and iron atoms in the first layer of the Cu(100) surface have been studied by molecular dynamics and the kinetic Monte Carlo method. The diffusion of embedded atoms results in the self-organization of bound iron-atom nanostructures. The time dependences of the number of most widespread nanostructures have been obtained. According to the results, the self-organization of embedded nanostructures can be divided into three stages in which the copper surface has significantly different morphologies.

Kolesnikov, S. V.

2014-05-01

315

Copper mobility in the Eastern Creek Volcanics, Mount Isa, Australia: evidence from laser ablation ICP-MS of iron-titanium oxides  

Microsoft Academic Search

The Palaeoproterozoic Eastern Creek Volcanics are a series of copper-rich tholeiitic basalts which occur adjacent to the giant sediment-hosted Mount Isa copper deposit in Queensland, Australia. The volcanic rocks are often cited as the source of metals for the deposit. New laser ablation ICP-MS analyses of iron–titanium oxides from the basalts provide evidence for the local mobilisation of copper during

Melissa J. Gregory

2006-01-01

316

Copper mobility in the Eastern Creek Volcanics, Mount Isa, Australia: evidence from laser ablation ICP-MS of iron-titanium oxides  

Microsoft Academic Search

The Palaeoproterozoic Eastern Creek Volcanics are a series of copper-rich tholeiitic basalts which occur adjacent to the giant sediment-hosted Mount Isa copper deposit in Queensland, Australia. The volcanic rocks are often cited as the source of metals for the deposit. New laser ablation ICP-MS analyses of iron-titanium oxides from the basalts provide evidence for the local mobilisation of copper during

Melissa J. Gregory

2006-01-01

317

Catalytic activity of systems based on coordination cyanides of copper, iron, ruthenium, and osmium in the reaction of ammonia synthesis  

Microsoft Academic Search

The purpose of the present investigation was to study the catalytic activity of systems based on cyano complexes of iron and its electronic analogs (ruthenium and osmium), and on coordination copper cyanides of the composition KâFe(Cu(CN)â)â and KFe(Cu(CN)â). The catalyst activities under 200 atm pressure were determined in an apparatus at space velocity of 15,000 h⁻¹ in the temperature range

Zh. I. Tkachenko; L. I. Pavlenko; Yu. A. Lyubchenko

1980-01-01

318

Limited effects of combined dietary copper deficiency\\/iron overload on oxidative stress parameters in rat liver and plasma  

Microsoft Academic Search

Copper (Cu) deficiency decreases the activity of Cu-dependent antioxidant enzymes such as Cu,zinc-superoxide dismutase (Cu,Zn-SOD) and may be associated with increased susceptibility to oxidative stress. Iron (Fe) overload represents a dietary oxidative stress relevant to overuse of Fe-containing supplements and to hereditary hemochromatosis. In a study to investigate oxidative stress interactions of dietary Cu deficiency with Fe overload, weanling male

Kevin A. Cockell; Andrew T. L. Wotherspoon; Bartholomeus Belonje; Melissa E. Fritz; René Madère; Nick Hidiroglou; Louise J. Plouffe; W. M. Nimal Ratnayake; Stan Kubow

2005-01-01

319

Impact of selenium, iron, copper and zinc in on\\/off Parkinson’s patients on L-dopa therapy  

Microsoft Academic Search

We have quantitated CSF and serum levels of Selenium, iron, copper and zinc by Atomic absorption spectrophotometer in 36 patients\\u000a with parkinson’s disease all on L-dopa therapy. Out of these 19 showed on or positive response to L-dopa where as 21 patients\\u000a showed on and off response. These data were compared with 21 healthy controls. The results showed that serum

G. A. Qureshi; A. A. Qureshi; S. A. Memon; S. H. Parvez

320

Cloud model experiments of the effect of iron and copper on tropospheric ozone under marine and continental conditions  

Microsoft Academic Search

Summary We have used a multi-phase cloud photochemistry model to investigate the influence of dissolved iron (Fe) and copper (Cu) on the in-cloud production and loss of ozone and ozone-related species. Comparison of the results of our simulations with and without Fe and Cu reactions for three different photochemical scenarios (marine, averaged continental and polluted continental) indicate that Fe and

J. Matthijsen; P. J. H. Builtjes; D. L. Sedlak

1995-01-01

321

Solidphase extraction of copper, iron and zinc ions on Bacillus thuringiensis israelensis loaded on Dowex optipore V-493  

Microsoft Academic Search

Bacillus thuringiensis israelensis loaded on Dowex optipore V-493 as new adsorbent for the separation–preconcentration of heavy metal ions has been proposed. The analytical conditions for the quantitative recoveries of copper(II), iron(III) and zinc(II) including pH, amounts of adsorbent, sample volume, etc. were investigated. The influences of alkaline and earth alkaline ions were also reported. The recovery values for the analytes

Mustafa Tuzen; Esra Melek; Mustafa Soylak

2008-01-01

322

Specific Inhibition of NEIL-initiated Repair of Oxidized Base Damage in Human Genome by Copper and Iron  

PubMed Central

Dyshomeostasis of transition metals iron and copper as well as accumulation of oxidative DNA damage have been implicated in multitude of human neurodegenerative diseases, including Alzheimer disease and Parkinson disease. These metals oxidize DNA bases by generating reactive oxygen species. Most oxidized bases in mammalian genomes are repaired via the base excision repair pathway, initiated with one of four major DNA glycosylases: NTH1 or OGG1 (of the Nth family) or NEIL1 or NEIL2 (of the Nei family). Here we show that Fe(II/III) and Cu(II) at physiological levels bind to NEIL1 and NEIL2 to alter their secondary structure and strongly inhibit repair of mutagenic 5-hydroxyuracil, a common cytosine oxidation product, both in vitro and in neuroblastoma (SH-SY5Y) cell extract by affecting the base excision and AP lyase activities of NEILs. The specificity of iron/copper inhibition of NEILs is indicated by a lack of similar inhibition of OGG1, which also indicated that the inhibition is due to metal binding to the enzymes and not DNA. Fluorescence and surface plasmon resonance studies show submicromolar binding of copper/iron to NEILs but not OGG1. Furthermore, Fe(II) inhibits the interaction of NEIL1 with downstream base excision repair proteins DNA polymerase ? and flap endonuclease-1 by 4–6-fold. These results indicate that iron/copper overload in the neurodegenerative diseases could act as a double-edged sword by both increasing oxidative genome damage and preventing their repair. Interestingly, specific chelators, including the natural chemopreventive compound curcumin, reverse the inhibition of NEILs both in vitro and in cells, suggesting their therapeutic potential.

Hegde, Muralidhar L.; Hegde, Pavana M.; Holthauzen, Luis M. F.; Hazra, Tapas K.; Rao, K. S. Jagannatha; Mitra, Sankar

2010-01-01

323

Regional distributions of manganese, iron, copper, and zinc in the brains of 6-hydroxydopamine-induced parkinsonian rats  

Microsoft Academic Search

Time courses of changes in manganese, iron, copper, and zinc concentrations were examined in regions of the brain of a 6-hydroxydopamine\\u000a (6-OHDA)-induced rat model of Parkinson’s disease using inductively coupled plasma mass spectrometry (ICP-MS). The concentrations\\u000a were simultaneously determined in brain section at the level of the substantia nigra 1, 3, 7, 10, 14, and 21 days after the\\u000a 6-OHDA treatment

Tohru Tarohda; Yasushi Ishida; Keiichi Kawai; Masayoshi Yamamoto; Ryohei Amano

2005-01-01

324

The effect of occupational lead exposure on blood levels of zinc, iron, copper, selenium and related proteins.  

PubMed

The study objective was to evaluate the effect of occupational lead exposure on blood concentrations of zinc, iron, copper, selenium and proteins related to them, such as transferrin, caeruloplasmin and haptoglobin. The examined group consisted of 192 healthy male employees of zinc-lead works. By the degree of lead exposure, the exposed group was subdivided into three subgroups. The control group was composed of 73 healthy male administrative workers. The markers of lead exposure (blood levels of lead and zinc protoporphyrin) were significantly elevated in the exposed group compared with the control group. Additionally, concentrations of copper and caeruloplasmin were raised. The significant increase in haptoglobin level was observed only in the low exposure group. Selenium levels were significantly decreased, whereas iron, zinc and transferrin levels were unchanged in the exposed group compared with the control group. There were positive correlations between the lead toxicity parameters and the copper and caeruloplasmin levels. In conclusion, the effect of occupational exposure to lead on the metabolism of trace metals appears to be limited. However, significant associations between lead exposure and levels of copper and selenium were shown. Changed levels of positive acute-phase proteins, such as caeruloplasmin and haptoglobin, were also observed. PMID:22923205

Kasperczyk, Aleksandra; Prokopowicz, Adam; Dobrakowski, Micha?; Pawlas, Natalia; Kasperczyk, S?awomir

2012-12-01

325

Steady-State rates of dissolution of stationary iron, cobalt, and nickel cylinders in liquid copper  

NASA Astrophysics Data System (ADS)

The steady-state rate of dissolution of each metal, ?, is determined as a function of its initial concentration in the melt at temperatures in the range 1468 to 1653 K. In the dissolution of an iron or a cobalt cylinder in pure liquid copper, ? increases with increasing temperature and log v varies linearly with 1/T. In every system investigated, ? deviates negatively from the dissolution rate, ?1, expressed by an equation in which it is proportional to the difference between the saturation concentration, X{i/s} (molar fraction), and the bulk concentration, X{i/b}, of a dissolving substance, ?, and follows another equation in which the dissolution rate is proportional to the difference between the activities of ? at X{i/s} and X{i/b} The dissolution rates of iron and cobalt are considered to be controlled by diffusion in the melt. The latter equation is derived from the assumption that the rate of diffusion is proportional to the activity gradient of ?. According to this equation, the deviation of ? from ?, is explained in terms of the ratio of the activity coefficient of ? at X{i/b}, ?i, to that at X{i/s}, ?{i/s}, and the ratio of (??/? X {i/b}) T,X {i/b}=0 to ??1/?X{b/i})T equals that of ?i, at infinite dilution to ?{i/s}. When the standard state of the activity is chosen so that it approaches Xi as Xi approaches zero, the logarithm of the rate constant defined by the latter equation is represented by a straight line as a function of 1/T for all the systems investigated.

Ohno, Reiichi

1982-06-01

326

Mixed messages in iron oxide–copper–gold systems of the Cloncurry district, Australia: insights from PIXE analysis of halogens and copper in fluid inclusions  

Microsoft Academic Search

Proterozoic rocks of the Cloncurry district in NW Queensland, Australia, are host to giant (tens to hundreds of square kilometers)\\u000a hydrothermal systems that include (1) barren regional sodic–calcic alteration, (2) granite-hosted hydrothermal complexes with\\u000a magmatic–hydrothermal transition features, and (3) iron oxide–copper–gold (IOCG) deposits. Fluid inclusion microthermometry\\u000a and proton-induced X-ray emission (PIXE) show that IOCG deposits and the granite-hosted hydrothermal complexes

Timothy Baker; Roger Mustard; Bin Fu; Patrick J. Williams; Guoyi Dong; Louise Fisher; Geordie Mark; Chris G. Ryan

2008-01-01

327

Spectrophotometric study of etodolac complexes with copper (II) and iron (III).  

PubMed

A rapid, simple, and selective method was developed for the determination of etodolac. The method depends on complexation of etodolac with copper (II) acetate and iron (III) chloride followed by extraction of complexes with dichloromethane and then measuring the extracted complexes spectrophotometrically at 684 and 385 nm in case of Cu (II) or Fe (III), respectively. Different factors affecting the reaction, such as pH, reagent concentration, and time, were studied. By use of Job's method of continuous variation, the molar ratio method, and elemental analysis, the stoichiometry of the reaction was found to be in the ratio of 1:2 and 1:3, metal:drug in the case of Cu (II) and Fe (III), respectively. The method obeys Beer's law in a concentration range of 2.00-9.00 and 0.50-2.00 mg/mL in case of Cu (II) and Fe (III), respectively. The stability of the complexes formed was also studied, and the reaction products were isolated for further investigation. The complexes have apparent molar absorptivities of about 32.14 +/- 0.97 and 168.32 +/- 1.12 for Cu (II) and Fe (III), respectively. The suggested procedures were successfully applied to the analysis of pure etodolac and its pharmaceutical formulations. The validity of the procedures was further ascertained by the method of standard additions, and the results were compared with other reported spectrophotometric methods and showed no significant difference in accuracy and precision. PMID:16526444

Amer, Sawsan M; El-Saharty, Yasser S; Metwally, Fadia H; Younes, Kareem M

2005-01-01

328

Microstructure and Mechanical Properties of As-Cast Ductile Irons Alloyed with Manganese and Copper  

NASA Astrophysics Data System (ADS)

The present investigation was carried out to study the effect of manganese and copper addition, singly as well as in combination, on the microstructure, micro-segregation, and mechanical properties of ductile irons. Alloy A (3.18C, 2.64Si, 0.45Mn), alloy B (3.35C, 2.51Si, 0.82Mn), alloy C (3.16C, 2.80Si, 1.08Mn, 0.56Cu), and alloy D (3.18C, 3.00Si, 1.04Mn, 1.13Cu) were melted and cast in the form of Y-block test pieces. The cast microstructures varied from ferrito-pearlitic in alloys A, B, and C to pearlitic in alloy D. However, on XRD analysis and SEM examination, the presence of martensite patches was also detected. There was a marginal decrease in nodule count in alloy B. In alloys C and D, nodule counts were higher, but the proportion of ferrite decreased drastically. Alloy D was found to be the strongest (UTS ? 800 MPa, El = 5%) with alloys A and C coming next in strength; while alloy B was weakest of the four. The presence of martensite patches in association with pearlite appears to be responsible for low toughness of these alloys. Microprobe analysis shows some silicon segregation near the graphite nodules and practically little segregation of manganese. Elemental mapping by FE-SEM does not indicate any manganese segregation.

Dasgupta, Ranjan Kumar; Mondal, Dipak Kumar; Chakrabarti, Ajit Kumar; Ganguli, Ashis Chandra

2012-08-01

329

Reactivity of food phenols with iron and copper ions: binding, dioxygen activation and oxidation mechanisms.  

PubMed

In this work, the affinity of common dietary phenols (gallic acid, caffeic acid, catechin, and rutin) for iron and copper ions was quantitatively investigated in neutral phosphate buffer as well as the reactivity of the complexes toward dioxygen. Contrasting behaviors were observed: because of the competing phosphate ions, Fe(III) binding is much slower than Fe(II) binding, which is rapidly followed by autoxidation of Fe(II) into Fe(III). With both ions, O2 consumption and H2O2 production are modest and the phenolic ligands are only slowly oxidized. By contrast, metal-phenol binding is fast with both Cu(I) and Cu(II). With Cu(I), O2 consumption and H2O2 production are very significant and the phenolic ligands are rapidly oxidized into a complex mixture of oligomers. The corresponding mechanism with Cu(II) is hampered by the preliminary rate-determining step of Cu(II) reduction by the phenols. The consequences of these findings for the stability and antioxidant activity of plant phenols are discussed. PMID:24700074

Nkhili, Ezzohra; Loonis, Michèle; Mihai, Simona; El Hajji, Hakima; Dangles, Olivier

2014-06-28

330

Heavy metal toxicity to fiddler crabs, Uca annulipes latreille and Uca triangularis (Milne Edwards): tolerance to copper, mercury, cadmium, and zinc  

SciTech Connect

The heavy metal pollution in marine and coastal ecosystems have become the focus of attention in recent years. The presence of heavy metals in the harbor waters of Visakhapatnam on the east cost of India deserves a special mention as it almost forms a repository for the industrial effluents and city's sewage. In the present investigation, the fiddler crabs Uca annulipes and Uca triangularis inhabiting this area were selected as the bioassay organisms to study their tolerance to four heavy metals: copper, cadmium, zinc, and mercury. An attempt has also been made to compare the results of the crabs from Harbor area with that of their counterparts from Bhimilipatnam (35 km from Visakhapatnam) where the brackish water does not receive the effluent from any of the industries.

Devi, V.U.

1987-12-01

331

Simultaneous Detection of Cadmium, Copper, and Lead using A Carbon Paste Electrode Modified with Carbamoylphosphonic Acid Self-Assembled Monolayer on Mesoporous Silica (SAMMS)  

SciTech Connect

A new sensor was developed for simultaneous detection of cadmium (Cd2+), copper (Cu2+), and lead (Pb2+), based on the voltammetric response at a carbon paste electrode modified with carbamoylphosphonic acid (acetamide phosphonic acid) self-assembled monolayer on mesoporous silica (Ac-Phos SAMMS). The adsorptive stripping voltammetry technique involves preconcentration of the metal ions onto Ac-Phos SAMMS under an open circuit, then electrolysis of the preconcentrated species, followed by a square wave potential sweep towards positive values. Factors affecting the preconcentration process were investigated. The voltammetric responses increased linearly with the preconcentration time from 1 to 30 minutes or with metal ion concentrations ranging from 10 to 200 ppb. The responses also evolved in the same fashion as adsorption isotherm in the pH range of 2-6. The metal detection limits were 10 ppb after 2 minutes preconcentration and improved to 0.5 ppb after 20 minutes preconcentration.

Yantasee, Wassana (BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB); Lin, Yuehe (BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB); Fryxell, Glen E.(BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB); Busche, Brad J.(BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB)

2004-01-30

332

Metallothionein Isoforms in Mytilus edulis (Mollusca, Bivalvia): Complementary DNA Characterization and Quantification of Expression in Different Organs after Exposure to Cadmium, Zinc, and Copper.  

PubMed

Reverse transcriptase-polymerase chain reaction has been used to isolate one metallothionein isoform (MT-20) complementary DNA from RNA extracted from mussel gill. Another cDNA, isolated by screening a Mytilus edulis cDNA mantle library using the first cDNA as probe, codes for the MT-10 IV isoform. Northern blot analysis using these cDNAs revealed different expression of these isoforms. Induction with CdC1(2) caused high levels of both MT messenger RNAs, especially the MT-20, which was induced by cadmium salt but not by zinc and copper salts. An induction of MT-10 was detected with ZnCl(2). These results show that genes encoding distinct MT isoforms are differentially regulated by heavy metals. PMID:10811960

Lemoine; Bigot; Sellos; Cosson; Laulier

2000-03-01

333

Comparison of microwave digestion with conventional wet ashing and dry ashing digestion for analysis of lead, cadmium, chromium, copper, and zinc in shellfish by flame atomic absorption spectroscopy.  

PubMed

A closed vessel microwave digestion procedure was developed for shellfish samples. This procedure was compared with wet and dry ash procedures for levels of lead, cadmium, chromium, copper, and zinc. Results obtained for microwave and conventional wet ash digestion were comparable. The dry ashing procedure produced results consistently lower than either of the other methods. Recoveries ranged from 80-92% for microwave and wet ashing procedures and 54-72% for the dry ashing procedure. Accuracy was also determined by analyzing lobster hepatopancreas marine reference material. Values for Pb, Cd, and Cr fell within the range specified for the reference material for all 3 digestion procedures; however, values were lower for Cu and Zn. Results of this study show that microwave digestion is comparable to wet ashing. PMID:1874704

McCarthy, H T; Ellis, P C

1991-01-01

334

Cadmium, copper, lead, and zinc determination in precipitation: A comparison of inductively coupled plasma atomic emission spectrometry and graphite furnace atomization atomic absorption spectrometry  

USGS Publications Warehouse

Selected trace element analysis for cadmium, copper, lead, and zinc in precipitation samples by inductively coupled plasma atomic emission Spectrometry (ICP) and by atomic absorption spectrometry with graphite furnace atomization (AAGF) have been evaluated. This task was conducted in conjunction with a longterm study of precipitation chemistry at high altitude sites located in remote areas of the southwestern United States. Coefficients of variation and recovery values were determined for a standard reference water sample for all metals examined for both techniques. At concentration levels less than 10 micrograms per liter AAGF analyses exhibited better precision and accuracy than ICP. Both methods appear to offer the potential for cost-effective analysis of trace metal ions in precipitation. ?? 1987 Springer-Verlag.

Reddy, M. M.; Benefiel, M. A.; Claassen, H. C.

1987-01-01

335

Expression of a Vacuole-Localized BURP-Domain Protein from Soybean (SALI3-2) Enhances Tolerance to Cadmium and Copper Stresses  

PubMed Central

The plant-specific BURP family proteins play diverse roles in plant development and stress responses, but the function mechanism of these proteins is still poorly understood. Proteins in this family are characterized by a highly conserved BURP domain with four conserved Cys-His repeats and two other Cys, indicating that these proteins potentially interacts with metal ions. In this paper, an immobilized metal affinity chromatography (IMAC) assay showed that the soybean BURP protein SALI3-2 could bind soft transition metal ions (Cd2+, Co2+, Ni2+, Zn2+ and Cu2+) but not hard metal ions (Ca2+ and Mg2+) in vitro. A subcellular localization analysis by confocal laser scanning microscopy revealed that the SALI3-2-GFP fusion protein was localized to the vacuoles. Physiological indexes assay showed that Sali3-2-transgenic Arabidopsis thaliana seedlings were more tolerant to Cu2+ or Cd2+ stresses than the wild type. An inductively coupled plasma optical emission spectrometry (ICP-OES) analysis illustrated that, compared to the wild type seedlings the Sali3-2-transgenic seedlings accumulated more cadmium or copper in the roots but less in the upper ground tissues when the seedlings were exposed to excessive CuCl2 or CdCl2 stress. Therefore, our findings suggest that the SALI3-2 protein may confer cadmium (Cd2+) and copper (Cu2+) tolerance to plants by helping plants to sequester Cd2+ or Cu2+ in the root and reduce the amount of heavy metals transported to the shoots.

Tang, Yulin; Cao, Yan; Qiu, Jianbin; Gao, Zhan; Ou, Zhonghua; Wang, Yajing; Zheng, Yizhi

2014-01-01

336

Expression of a Vacuole-Localized BURP-Domain Protein from Soybean (SALI3-2) Enhances Tolerance to Cadmium and Copper Stresses.  

PubMed

The plant-specific BURP family proteins play diverse roles in plant development and stress responses, but the function mechanism of these proteins is still poorly understood. Proteins in this family are characterized by a highly conserved BURP domain with four conserved Cys-His repeats and two other Cys, indicating that these proteins potentially interacts with metal ions. In this paper, an immobilized metal affinity chromatography (IMAC) assay showed that the soybean BURP protein SALI3-2 could bind soft transition metal ions (Cd2+, Co2+, Ni2+, Zn2+ and Cu2+) but not hard metal ions (Ca2+ and Mg2+) in vitro. A subcellular localization analysis by confocal laser scanning microscopy revealed that the SALI3-2-GFP fusion protein was localized to the vacuoles. Physiological indexes assay showed that Sali3-2-transgenic Arabidopsis thaliana seedlings were more tolerant to Cu2+ or Cd2+ stresses than the wild type. An inductively coupled plasma optical emission spectrometry (ICP-OES) analysis illustrated that, compared to the wild type seedlings the Sali3-2-transgenic seedlings accumulated more cadmium or copper in the roots but less in the upper ground tissues when the seedlings were exposed to excessive CuCl2 or CdCl2 stress. Therefore, our findings suggest that the SALI3-2 protein may confer cadmium (Cd2+) and copper (Cu2+) tolerance to plants by helping plants to sequester Cd2+ or Cu2+ in the root and reduce the amount of heavy metals transported to the shoots. PMID:24901737

Tang, Yulin; Cao, Yan; Qiu, Jianbin; Gao, Zhan; Ou, Zhonghua; Wang, Yajing; Zheng, Yizhi

2014-01-01

337

On-line copper and iron removal and selenium(VI) pre-reduction for the determination of total selenium by flow-injection hydride generation-inductively coupled plasma optical emission spectrometry  

Microsoft Academic Search

Selenium was determined in samples with high copper and iron contents by hydride generation-inductively coupled plasma optical emission spectrometry (HG-ICP-OES) after flow-injection (FI) on-line copper and iron removal and selenium(VI) reduction. A Dowex 1X-8 anion-exchange microcolumn was used for the separation of selenium from copper and iron as their chloro-complexes. Se(VI) was then reduced on-line by heating a PTFE coiled

Jorge Stripeikis; Mabel Tudino; Osvaldo Troccoli; Rodolfo Wuilloud; Roberto Olsina; Luis Martinez

2001-01-01

338

Bioaccumulation of cadmium by growing Zygosaccharomyces rouxii and Saccharomyces cerevisiae.  

PubMed

Bioaccumulation via growing cells is a potential technique for heavy metal removal from food materials. The cadmium bioaccumulation characteristics by growing Zygosaccharomyces rouxii and Saccharomyces cerevisiae were investigated. Z. rouxii displayed powerful cadmium removal ability at low cadmium concentrations, which mainly depended on the intracellular cadmium bioaccumulation. The percentage of intracellular cadmium bioaccumulation of both yeasts obviously decreased with the increase of initial biomass and cadmium concentrations. Low pH and elevated concentrations of zinc and copper significantly decreased the intracellular cadmium bioaccumulation of both yeasts but improved the cadmium tolerance and the cell-surface cadmium bioaccumulation of Z. rouxii. Cadmium removal of Z. rouxii was improved by zinc and copper conditionally. Z. rouxii that possessed more powerful cadmium tolerance and removal ability at low pH and high concentration of competing ions can be developed into a potential cadmium removal agent using in complex food environment in future. PMID:24440489

Li, Chunsheng; Jiang, Wei; Ma, Ning; Zhu, Yinglian; Dong, Xiaoyan; Wang, Dongfeng; Meng, Xianghong; Xu, Ying

2014-03-01

339

Genetic Effects on Toxic and Essential Elements in Humans: Arsenic, Cadmium, Copper, Lead, Mercury, Selenium, and Zinc in Erythrocytes  

Microsoft Academic Search

Background and o B jectives : An excess of toxic trace elements or a deficiency of essential ones has been implicated in many common diseases or public health problems, but little is known about causes of variation between people living within similar environments. We estimated effects of per - sonal and socio economic characteristics on concentrations of arsenic (As), cadmium

John B. Whitfield; Veronica Dy; Robert McQuilty; Gu Zhu; Andrew C. Heath; Grant W. Montgomery; Nicholas G. Martin

2010-01-01

340

Seasonal and locational effects on serum, milk, liver and kidney chromium, manganese, copper, zinc, and iron concentrations of dairy cows.  

PubMed

Chromium (Cr), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) concentrations were quantified in serum (n = 112), milk (n = 112), liver (n = 70), and kidney samples (n = 67) of dairy cows from an iron-steel processing region (Payas-Iskenderun) and from an area free of industrial pollution (Antakya) in Hatay, located in Southern Turkey. Samples were collected in the summer and winter and element determinations were carried out by inductively coupled plasma-atomic emission spectrometry. The mean concentrations of selected elements in serum were found to be similar in both regions. Milk samples collected from the nonindustrial region in the summer had higher Cr, Mn, and Zn concentrations than the polluted region. The liver Cu and kidney Mn levels of samples taken from the industrial region in winter were higher than samples of the unpolluted region. Copper and Fe concentrations in milk, Cr, Mn, Zn, and Fe levels in the liver, and Cr, Cu, Zn, and Fe levels in kidney samples were not found to be different among the regions in both seasons. Copper concentrations were below the critical level in the 25% of serum and 32% of liver samples analyzed in this study. Fifteen percent of serum samples and most of the liver samples had lower amounts of Zn than other reported studies. Although slight differences were observed between the industrial and nonindustrial regions, industrial activities and seasonal changes had no significant effect on selected element concentrations on cows and their milk. PMID:15051900

Erdogan, Suat; Celik, Sefa; Erdogan, Zeynep

2004-04-01

341

Factors influencing the DNA nuclease activity of iron, cobalt, nickel, and copper chelates.  

PubMed

A library of complexes that included iron, cobalt, nickel, and copper chelates of cyclam, cyclen, DOTA, DTPA, EDTA, tripeptide GGH, tetrapeptide KGHK, NTA, and TACN was evaluated for DNA nuclease activity, ascorbate consumption, superoxide and hydroxyl radical generation, and reduction potential under physiologically relevant conditions. Plasmid DNA cleavage rates demonstrated by combinations of each complex and biological co-reactants were quantified by gel electrophoresis, yielding second-order rate constants for DNA(supercoiled) to DNA(nicked) conversion up to 2.5 × 10(6) M(-1) min(-1), and for DNA(nicked) to DNA(linear) up to 7 × 10(5) M(-1) min(-1). Relative rates of radical generation and characterization of radical species were determined by reaction with the fluorescent radical probes TEMPO-9-AC and rhodamine B. Ascorbate turnover rate constants ranging from 3 × 10(-4) to 0.13 min(-1) were determined, although many complexes demonstrated no measurable activity. Inhibition and Freifelder-Trumbo analysis of DNA cleavage supported concerted cleavage of dsDNA by a metal-associated reactive oxygen species (ROS) in the case of Cu(2+)(aq), Cu-KGHK, Co-KGHK, and Cu-NTA and stepwise cleavage for Fe(2+)(aq), Cu-cyclam, Cu-cyclen, Co-cyclen, Cu-EDTA, Ni-EDTA, Co-EDTA, Cu-GGH, and Co-NTA. Reduction potentials varied over the range from -362 to +1111 mV versus NHE, and complexes demonstrated optimal catalytic activity in the range of the physiological redox co-reactants ascorbate and peroxide (-66 to +380 mV). PMID:21815680

Joyner, Jeff C; Reichfield, Jared; Cowan, J A

2011-10-01

342

Influence of iron and copper oxides on polychlorinated diphenyl ether formation in heterogeneous reactions.  

PubMed

Polychlorinated diphenyl ether (PCDE) has attracted great attention recently as an important type of environmental pollutant. The influence of iron and copper oxides on formation of PCDEs was investigated using laboratory-scale flow reactors under air and under nitrogen at 350 °C, a temperature corresponding to the post-combustion zone of a municipal solid waste incinerator. The results show that the 2,2',3,4,4',5,5',6-otachlorodiphenyl ether (OCDE) formed from the condensation of pentachlorophenol (PCP) and 1,2,4,5-tetrachlorobenzene (Cl4Bz) is the predominant congener formed on the SiO2/Fe2O3 surface with and without oxygen. This indicated that HCl elimination between PCP and 1,2,4,5-Cl4Bz molecules formed 2,2',3,4,4',5,5',6-OCDE in the presence of Fe2O3. On the other hand, decachlorodiphenyl ether, nonachlorodiphenyl ether, and OCDE were the dominant products on the SiO2/CuO surface without oxygen, although the 2,2',3,4,4',5,5',6-OCDE was the dominant product on the SiO2/CuO surface with oxygen. Therefore, the presence of Fe2O3 and CuO influences the formation and homologue distribution of PCDEs, which shifted towards the lower chlorinated species. Fe2O3 can promote both the condensation and dechlorination reaction without oxygen. On the contrary, with oxygen, Fe2O3 suppresses the condensation of chlorobenzene and chlorophenol to form PCDEs and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs). CuO can increase the formation of lower chlorinated PCDEs and PCDDs without oxygen. In conclusion, the different fly ash components have a major influence on PCDE emissions. PMID:23440438

Liu, Wenxia; Shen, Lianfeng; Zhang, Fawen; Liu, Wenbin; Zheng, Minghui; Yang, Xitian

2013-08-01

343

Iron, zinc, copper and selenium status of breast-fed infants and infants fed trace element fortified milk-based infant formula.  

PubMed

Infants were fed cow's milk-based formulas containing 4 mg of iron/l from 1.5 to 6 months of age and their hematological status was compared to infants receiving the same formula but with 7 mg of iron/l and with breast-fed infants. One formula with 4 mg of iron/l contained iron as ferrous sulfate, in another, part of the iron was provided as bovine lactoferrin. We also studied the effect of selenium (10 micrograms/l) and copper (0.4 mg/l) supplementation on selenium and copper status. There were no significant differences in hematological indices among the groups at 6 months of age; all infants had satisfactory iron status. Serum transferrin receptor levels, a potential novel indicator of iron status, were highest in breast-fed infants, suggesting a cellular need for iron, and lowest in infants receiving formula with 7 mg of iron/l. Selenium status, as assessed by serum glutathione peroxidase activity, was similar at 6 months of age in breast-fed infants and infants fed formula fortified with selenium but lower in infants fed unfortified formula. The lowest levels of glutathione peroxidase activity were found in infants fed the highest concentration of iron (7 mg/l). Serum copper concentrations were similar in all groups, but the lowest levels were found in infants fed the highest concentration of iron. These results suggest that 4 mg of iron/l is adequate for infants up to 6 months of age and that higher levels may have some negative effects. PMID:8025391

Lönnerdal, B; Hernell, O

1994-04-01

344

Concentrations of mercury, cadmium, lead and copper in fruiting bodies of edible mushrooms in an emission area of a copper smelter and a mercury smelter  

Microsoft Academic Search

Four metals were determined by AAS techniques in 56 samples of 23 wild mushroom species collected in a heavily polluted area in eastern Slovakia in 1997 and 1998. The area has been contaminated from historical polymetallic ores mining and smelting and by emissions from a mercury smelter between 1969 and 1993 and from a copper smelter since 1951. No significant

L. Svoboda; K Zimmermannová; P Kala?

2000-01-01

345

Synthesis, Spectroscopic, and Electrochemical Characterization of a Schiff Base: 4,4?-bis[(4- diethylaminosalicylaldehyde)diphenyl methane]diimine and Its Complexes With Copper(II), Cobalt(II), and Cadmium(II)  

Microsoft Academic Search

The synthesis of a new ligand tetradentate Schiff base: 4,4?-bis[(4-diethyl aminosalicylaldehyde) diphenyl methane] diimine (H2L), obtained by condensation of 4,4?-diaminodiphenyl methane with 4-diethylaminosalicylaldehyde, and its complexes with copper(II), cobalt(II) and cadmium(II), is described. The metal complexes were characterized by elemental analysis, by UV-visible, infrared, and EPR spectroscopy, by cyclic voltammetry, and by thermal analysis (DTA-TG). The coordination of the metal

Sonia Benabid; Tahar Douadi; Houria Debab; Marc De Backer; François-Xavier Sauvage

2012-01-01

346

Structural state of surface layers of aluminum after laser alloying using a mixture of copper and iron powders  

NASA Astrophysics Data System (ADS)

X-ray diffraction, metallographic, and electron-microscopic methods were used to study the regularities of the structure formation in the surface layers of aluminum upon pulse laser alloying using copper and iron powders taken in an atomic ratio of two to one. It is shown that, in the zone of laser alloying, a quasicrystalline phase can form, which leads to a considerable increase in microhardness. The effect of the thickness of the alloying layer on the structural and phase state of the laser-affected zone is analyzed.

Girzhon, V. V.; Smolyakov, A. V.; Tantsyura, I. V.

2008-10-01

347

Attenuation in iron of neutrons produced by 120 GeV/c positive hadrons on a thick copper target  

NASA Astrophysics Data System (ADS)

A deep penetration experiment in a thick iron shield was carried out at CERN, at the CERN-EU high-energy Field (CERF) facility. A 120 GeV/c positive hadron beam impinged on a 50 cm thick copper target located inside an irradiation cave covered by an iron shield, the thickness of which could be varied from 40 to 240 cm. Measurements of neutron fluence and ambient dose equivalent were performed with a Bonner Sphere Spectrometer and an extended-range rem counter and the results compared with Monte Carlo simulations carried out with the FLUKA code. A comparison with literature data shows an acceptable agreement. A discussion is also given on the contribution of the neutron background and of its influence on a deep penetration experiment.

Agosteo, Stefano; Pozzi, Fabio; Silari, Marco; Ulrici, Luisa

2013-10-01

348

Influence of iron and copper consumption on weight gain and oxidative stress in adipose tissue of Wistar rats  

PubMed Central

The aim of the present study was to assess the effect of iron and copper consumption on weight gain and development of oxidative stress in adipose tissue of rats. Control rats obtained pure drinking water. Iron-treated groups of animals obtained FeSO4•12H2O with drinking water in concentrations of 3 and 6 mg/l, while copper-treated rats obtained CuSO4 in concentrations of 4.88 and 9.76 mg/l. The animals of the 6th group received a mixture of FeSO4•12H2O and CuSO4 in the respective concentrations of 3 and 4.88 mg/l in drinking water. All animals received a standard chow. The final weight of rats from all the experimental groups, especially in those obtaining the combination of iron and cooper, exceeded the control values. Maximal weight of fat pads was observed in animals receiving drinking water with 3 mg/l FeSO4•12H2O, 4.88 and 9.76 mg/l CuSO4, and the mixture of FeSO4•12H2O and CuSO4. The maximal intensity of free radical processes, as estimated by the concentration of fluorescent modified amino acids and the intensity of chemiluminescence in adipose tissue homogenates, was observed in rats obtaining iron in the concentration of 3 mg/l in the drinking water.

Ajsuvakova, Olga P.; Shehtman, Alexandr M.; Boev, Viktor M.; Nikonorov, Alexandr A.

2012-01-01

349

Identification of genes involved in the toxic response of Saccharomyces cerevisiae against iron and copper overload by parallel analysis of deletion mutants.  

PubMed

Iron and copper are essential nutrients for life as they are required for the function of many proteins but can be toxic if present in excess. Accumulation of these metals in the human body as a consequence of overload disorders and/or high environmental exposures has detrimental effects on health. The budding yeast Saccharomyces cerevisiae is an accepted cellular model for iron and copper metabolism in humans primarily because of the high degree of conservation between pathways and proteins involved. Here we report a systematic screen using yeast deletion mutants to identify genes involved in the toxic response to growth-inhibitory concentrations of iron and copper sulfate. We aimed to understand the cellular responses to toxic concentrations of these two metals by analyzing the different subnetworks and biological processes significantly enriched with these genes. Our results indicate the presence of two different detoxification pathways for iron and copper that converge toward the vacuole. The product of several of the identified genes in these pathways form molecular complexes that are conserved in mammals and include the retromer, endosomal sorting complex required for transport (ESCRT) and AP-3 complexes, suggesting that the mechanisms involved can be extrapolated to humans. Our data also suggest a disruption in ion homeostasis and, in particular, of iron after copper exposure. Moreover, the identification of treatment-specific genes associated with biological processes such as DNA double-strand break repair for iron and tryptophan biosynthesis for copper suggests differences in the mechanisms by which these two metals are toxic at high concentrations. PMID:17785683

Jo, William J; Loguinov, Alex; Chang, Michelle; Wintz, Henri; Nislow, Corey; Arkin, Adam P; Giaever, Guri; Vulpe, Chris D

2008-01-01

350

Bacterial Reduction of Copper-Contaminated Ferric Oxide: Copper Toxicity and the Interaction Between Fermentative and Iron-Reducing Bacteria  

Microsoft Academic Search

.   Fe(III) oxide is an important heavy-metal sink, and bacteria are responsible for much of the Fe(III) reduced in nonsulfidogenic\\u000a aquatic environments, yet factors governing the bacterial reduction of heavy metal–contaminated iron oxide are largely unknown.\\u000a In this study with a stabilized bacterial consortium enriched from metal-contaminated sediments, we demonstrate that Cu toxicity\\u000a impedes anaerobic carbon oxidation and bacterial reduction

J. T. Markwiese; P. J. S. Colberg

2000-01-01

351

Bosonics in the copper and iron based high transition temperature superconductors  

NASA Astrophysics Data System (ADS)

It has been long established that the phenomenon of superconductivity is administered by lattice deformations (phonons) which act to pair electrons into spinless bosons free to condense into a coherent ground state. This superconducting phase is protected up to a critical temperature above which thermal fluctuations are potent enough to destroy the resistance free phase. The strength of this phonon mediation has been calculated by strong coupling theory and found to be capable of accommodating pairing up to near 40 K. So with the advent of copper-oxide (cuprate) superconductors boasting transitions temperatures exceeding 90 K it was clear that these material represented a new breed of superconducting physics. More than twenty years after the initial discovery of these high-transition temperatures the most basic questions are yet to be answered, the most fundamental of which is by what mechanism does pairing occur? The field splits between those who feel that a boson mediator is still necessary to act as the virtual glue which binds electrons into cooper pairs while others insist that really the Coulomb force alone is enough to induce pairing physics. Even within the boson-seeker community there is no consensus on what particular type of boson is contained in this system whether it be a lattice excitation or spin excitation. This answer has been clouded by previous experimental results on the hole-doped cuprates which have made strong cases for every scenario rendering them largely inconclusive. For this answer though it is possible to explore materials that have not yet been clouded by conflicting results by performing the first high resolution ultra-high-vacuum low-temperature scanning tunneling microscopy (STM) study of an electron-doped cuprate. A distinct and unambiguous bosonic mode is found at energy near 10.5 meV. Through comparison with other experimental data it is found that this mode does not fit the characteristics of a phonon. It is found, through comparison with neutron scattering experiments on the same sample, that this mode is consistent with a spin collective mode. Further more it is found that this mode is linked with the strength of superconductivity nominating it as the possible electron pairing mechanism. Doping and temperature dependence studies are performed to investigate this possibility. Finally the same procedures developed can be applied to the newly discovered iron based superconductors which may represent yet another type of new superconductor physics. Initial results on the first bosonic mode STM study of SrFe 2-xCoxAs 2 and BaFe2-xCo xAs2 are presented.

Niestemski, Francis Charles

352

Coprecipitation with yttrium phosphate as a separation technique for iron(III), lead, and bismuth from cobalt, nickel, and copper matrices.  

PubMed

The coprecipitation behavior of 44 elements (47 ions because of chromium(III,VI), arsenic(III,V), and antimony(III,V)) with yttrium phosphate was investigated at various pHs. Yttrium phosphate could quantitatively coprecipitate iron(III), lead, bismuth, and indium over a wide pH range; however, 18 ions, including alkali metals and oxo anions, such as vanadium(V), chromium(VI), molybdenum(VI), tungsten(VI), germanium(IV), arsenic(III,V), selenium(IV), and tellurium(VI), were scarcely collected. In addition, 19 ions, including cobalt, nickel, and copper(II), were hardly coprecipitated at pHs below about 3. Based on these results, the separation of iron(III), lead, and bismuth from cobalt, nickel, and copper(II) matrices was investigated. Iron(III), lead, and bismuth ranging from 0.5 to 25mug could be separated effectively from a solution containing 0.5g of cobalt, nickel, or copper at pH 3.0. The separated iron(III), lead, and bismuth could be determined by inductively coupled plasma atomic emission spectrometry using internal standardization. The detection limits (3sigma, n=7) of iron(III), lead, and bismuth were 0.008, 0.137, and 0.073mug, respectively. The proposed method was applied to the analyses of metals and chlorides of cobalt, nickel, and copper. PMID:18970141

Kagaya, Shigehiro; Araki, Yasuko; Hirai, Noriyasu; Hasegawa, Kiyoshi

2005-07-15

353

Determination of iron and copper in seawater at pH 1.7 with a new commercially available chelating resin, NTA Superflow  

Microsoft Academic Search

The use of a commercially available chelating resin with NTA-type functional groups for concentration of trace metals from seawater is described. Trace metal recoveries from this NTA Superflow chelating resin are pH dependent. At a pH of ?2 only iron(III) and copper are quantitatively recovered from the resin. Iron(II) cannot be quantitatively recovered from this resin below a pH of

Maeve C. Lohan; Ana M. Aguilar-Islas; Robert P. Franks; Kenneth W. Bruland

2005-01-01

354

Synthesis of a chitosan derivative recognizing planar metal ion and its selective adsorption equilibria of copper(II) over iron(III) 1  

Microsoft Academic Search

In order to improve the selectivity of copper(II)\\/iron(III), crosslinked N-(2-pyridyhnethyl)chitosan (PMC) with lower affinity for iron(III) was synthesized by crosslinking the Schiff's base formed in order to prevent amino groups to be metal adsorption sites from a attack of (chloromethyl)oxirane. The final chitosan derivative, PMC, was obtained by reducing the imine moiety of the Schiff's base with sodium borohydride. By

Yoshinari Baba; Koichi Masaaki; Yoshinobu Kawano

1998-01-01

355

Molecular Mechanisms of the Epithelial Transport of Toxic Metal Ions, Particularly Mercury, Cadmium, Lead, Arsenic, Zinc, and Copper. Progress Report, January 1, 1977--December 31, 1977.  

National Technical Information Service (NTIS)

Investigations were undertaken to understand the mode of transepithelial transport of toxic metal ions across the gastrointestinal tract, with primary attention given to cadmium. The toxic effects of cadmium on the metabolism of vitamin D and calcium were...

R. H. Wasserman

1977-01-01

356

Effect of excess dietary iron as ferrous sulfate and excess dietary ascorbic acid on liver zinc, copper and sulfhydryl groups and the ovary  

SciTech Connect

Female guinea pigs of the NIH 13/N strain, weighing between 475 and 512 g, were fed diets supplemented with 50 to 2500 mg of iron per kg of diet as ferrous sulfate and 0.2 to 8.0 g of ascorbic acid per kg of diet. A significant effect was observed on tissue copper and zinc, ovary weight and liver protein sulfhydryl groups. The mean ovary weight for guinea pigs fed 2500 mg of iron was significantly less than that of animals fed 50 mg of iron, 0.045 +/- 0.012 g and 0.061 +/- 0.009 g, respectively. Liver zinc content of animals fed 2500 mg of iron and 200 mg of ascorbic acid per kg of diet was significantly less than that of animals fed 50 mg of iron and 200 mg of ascorbic acid, 16.3 +/- 3.3 ..mu..g and 19.6 +/- 1.6 ..mu..g, respectively. There was no difference in liver copper due to dietary iron, but when dietary ascorbic acid was increased to 8 g per kg of diet, there was a significant decrease (from 22.8 +/- 8.1 ..mu..g to 10.5 +/- 4.8 ..mu..g) in liver copper. Excess dietary ascorbic acid decreased ovarian zinc significantly when increased to 8 g per kg of diet, 2929 +/- 919 ..mu..g vs 1661 +/- 471 ..mu..g, respectively, when compared to the control group.

Edwards, C.H.; Adkins, J.S.; Harrison, B.

1986-03-05

357

Preconcentration and separation of copper(II), cadmium(II) and chromium(III) in a syringe filled with 3-aminopropyltriethoxysilane supported on silica gel.  

PubMed

In this study, a syringe was filled with silica gel loaded with 3-aminopropyltriethoxysilane, for the separation and preconcentration of copper, cadmium and chromium prior to their determination by graphite furnace atomic absorption spectrometry (GFAAS) in seawater. For this purpose, a syringe was filled with 0.5 g of modified silica gel and the sample solution was drawn into the syringe and ejected back again. The analyte elements were quantitatively retained at pH 5. Then, the elements sorbed by the silica gel were eluted with 2.0 M of HCl and determined by GFAAS. At optimum conditions, the recovery of Cu, Cd and Cr were 96-98%. Detection limits (3delta) were 6.6, 7.5 and 6.0 micro g L(-1) for Cu, Cd and Cr, respectively. The elements could be concentrated by drawing and discharging several portions of sample successively but eluting only once. Cu, Cd and Cr added to a seawater sample were quantitatively recovered (>95%) in the range of the 95% confidence level. The method proposed in this paper was compared with a column technique. Optimum experimental conditions, reproducibility, precision and recoveries of both techniques are the same, but the syringe technique is much faster, easier and more practical than the column technique. It is a portable system and allows one to make the sorption process in the source of sample. In addition, the risk of contamination is less than in the column technique. PMID:12434258

Tokman, Nilgun; Akman, Suleyman; Ozcan, Mustafa; Koklu, Unel

2002-11-01

358

Neutron production in collisions between carbon nuclei of energy 2 GeV per nucleon and carbon, aluminum, copper, cadmium, and lead nuclei  

NASA Astrophysics Data System (ADS)

Double-differential cross sections for neutron production were measured by the time-of-flight method for the interactions between carbon nuclei of energy 2 GeV per nucleon and carbon, aluminum, copper, cadmium, and lead nuclei. These measurements were performed for angles of 30°, 53°, and 90° in the neutron-energy range fromseveral hundred keVunits to 300MeV. The phenomenologicalmodel of four moving sources was used as a basis in analyzing experimental results and in estimating the contribution to neutron emission from various reaction stages. The temperature parameters determined from the slope of the neutron energy spectra proved to be 22 ± 2 MeV for a hot source (fireball) and 4.5 ± 0.3 MeV for the stage of thermal fragmentation of highly excited heavy nuclear residues. The relative contribution of these two sources to the total neutron yield is independent of the type of the target nucleus and is about 42%, on average.

Yurevich, V. I.; Yakovlev, R. M.; Lyapin, V. G.

2012-02-01

359

Induction of DNA double-strand breaks in the H4IIE cell line exposed to environmentally relevant concentrations of copper, cadmium, and zinc, singly and in combinations.  

PubMed

Xenobiotics, including heavy metals, exist in nature as complex mixtures of compounds with possible interactions. Induction of DNA damage such as DNA strand breaks may exert detrimental consequences to both individuals and populations. In this study, the induction of DNA double-strand breaks was assessed using the H4IIE rat hepatoma cell line following exposure to high and environmentally relevant concentrations of chloride salts of the metals cadmium (Cd), copper (Cu), and zinc (Zn), both singly and in combination. DNA strand break analysis was performed using agarose gel electrophoresis. Median molecular lengths were calculated from fragment size distributions acquired from gel image data and were used as a quantitative measure of DNA double-strand break induction. Exposure to high concentrations of Cu and Cd in combination produced a significant increase in the occurrence of DNA strand break. However, exposing cells to high concentrations of Cu, Cd, and Zn in combination resulted in significantly lower DNA double-strand break compared to control cells. Addition of low Zn to the Cd/Cu mixture restored DNA damage level back to that of the control. Environmentally relevant concentrations of Cd, Cu, and Zn did not appear to induce DNA strand breaks in the H4IIE cell line. PMID:19184730

Haldsrud, Renate; Krøkje, Ase

2009-01-01

360

Cadmium, copper and zinc toxicity effects on growth, proline content and genetic stability of Solanum nigrum L., a crop wild relative for tomato; comparative study.  

PubMed

Plants like other organisms are affected by environmental factors. Cadmium, copper and zinc are considered the most important types of pollutants in the environment. In this study, a comparison of growth and biochemical parameters between the crop wild relative (CWR) Solanum nigrum versus its cultivated relative Solanum lycopersicum to different levels of Cu, Zn and Cd stress were investigated. The presence of ZnSO4 and CuSO4 in Murashige and Skoog medium affected severely many growth parameters (shoot length, number of roots and leaves, and fresh weight) of both S. nigrum and S. lycopersicum at high levels. On the other hand, CdCl2 significantly reduced most of the studied growth parameters for both species. S. nigrum exhibited higher tolerance than S. lycopersicum for all types of stress. In addition, results show that as stress level increased in the growing medium, proline content of both S. nigrum and S. lycopersicum increased. A significant difference was observed between the two species in proline accumulation as a result of stress. In addition, a higher accumulation rate was observed in the crop wild relative (S. nigrum) than in cultivated S. lycopersicum. Changes in Inter-simple sequence repeat (ISSR) pattern of CuSO4 treated S. nigrum and S. lycopersicum plants were also observed. In conclusion, based on growth and biochemical analysis, S. nigrum showed higher level of metals tolerance than S. lycopersicum which indicates the possibility of using it as a crop wild relative for S. lycopersicum. PMID:24554836

Al Khateeb, Wesam; Al-Qwasemeh, Hajer

2014-01-01

361

Trace element concentrations (mercury, cadmium, copper, zinc, lead, aluminium, nickel, arsenic, and selenium) in some aquatic birds of the southwest Atlantic coast of France.  

PubMed

Trace elements (mercury [Hg], cadmium [Cd], copper [Cu], zinc [Zn], lead [Pb], aluminium [Al], nickel [Ni], arsenic [As], and selenium [Se]) were investigated using inductively coupled plasma-mass spectrometry in liver, kidney, muscle, and feather of aquatic birds wintering or inhabiting the wetlands situated on the Southwest Atlantic coast of France. A majority of greylag geese, red knots, and grey plovers were collected from among hunter-shot animals. The relation between residue concentrations, age (juvenile vs. adult), and sex was investigated. Trace elements were lower than threshold levels of toxicity, except for Pb. Greylag geese sampled could be considered Pb-poisoned. These consequential levels of contamination could be the result of the ingestion of Pb-shot from ammunition used in hunting areas they crossed during migration. Cd accumulation increased with age, whereas Pb levels in feathers were lower in adult birds in connection with moulting. As was influenced by sex. Female birds displayed higher concentrations in liver and feathers than did male birds. PMID:19763676

Lucia, Magali; André, Jean-Marc; Gontier, Karine; Diot, Nicolas; Veiga, Jesus; Davail, Stéphane

2010-04-01

362

The impact of a copper smelter on adjacent soil zinc and cadmium fractions and soil organic carbon  

Microsoft Academic Search

Purpose  We investigated the chemical fractions of Zn, Cd and Cu in soils collected from positions at different distances from a copper\\u000a smelter and studied the relationships between distribution patterns of Zn, Cd and Cu, fractions and soil organic carbon (SOC),\\u000a especially “black carbon” (BC), in contaminated soils. The relationships between soil particle size and concentrations of\\u000a Zn and Cd in

Ling Liu; Longhua Wu; Yongming Luo; Changbo Zhang; Yugen Jiang; Xiya Qiu

2010-01-01

363

Preparing Copper Powder from Cemented Copper.  

National Technical Information Service (NTIS)

Techniques were developed for preparing metallurgical-grade copper powder from industrially produced cement copper. Flotation was used for rejecting discrete gangue particles, acid leaching to remove residual iron and aluminum, hydrogen reduction to elimi...

J. K. Winter L. G. Evans R. D. Groves

1971-01-01

364

[Vitamin and mineral supplements in the diet of military personnel: effect on the balance of iron, copper and manganese, immune reactivity and physical work-capacity].  

PubMed

Conducted with the participation of 50 students of military educational study the effect of various vitamin and mineral complexes for the provision by the body naturally iron, copper and manganese on the immune and physical status. Found that diets enriched BMV was accompanied by a significant delay in the micro-elements, mainly iron, which indicates a deficiency of these bioelements in chickens Santo during the summer. Under the influence of vitamin-mineral complexes significantly increased rates of natural and specific immunity. As the delay increases significantly increased iron medical indicators of immunological reaction efficiency and physical performance. PMID:22686030

Za?tseva, I P; Nosolodin, V V; Za?tsev, O N; Gladkikh, I P; Koznienko, I V; Beliakov, R A; Arshinov, N P

2012-03-01

365

Iron  

Microsoft Academic Search

Iron poisoning causes its metabolic effects in proportion to the concentrations of free iron. Toxicity is therefore related to dose ingested. The amount of iron in different salts varies, and iron concentrations may rise and fall, making plasma concentrations difficult to interpret in acute poisoning. Clinical features include severe gastrointestinal irritation, cardiovascular collapse and direct organ damage to liver and

D. Nicholas Bateman

2007-01-01

366

An association among iron, copper, zinc, and selenium, and antioxidative status in dyslipidemic pediatric patients with glycogen storage disease types IA and III  

Microsoft Academic Search

Dyslipidemia in patients with glycogen storage disease types Ia (GSD Ia) and III (GSD III) does not lead to premature atherosclerosis. The aim of this study was to investigate the association among serum copper (Cu), zinc (Zn), iron (Fe), and selenium (Se) concentrations, and their carrier proteins: ceruloplasmin, albumin, and related antioxidant enzyme activities [superoxide dismutase (SOD), catalase (CAT), glutathione

Sema Kalkan Ucar; Mahmut Coker; Eser Sözmen; Damla Goksen Simsek; Sukran Darcan

2010-01-01

367

Preconcentration and determination of iron and copper in spice samples by cloud point extraction and flow injection flame atomic absorption spectrometry.  

PubMed

A flow injection (FI) cloud point extraction (CPE) method for the determination of iron and copper by flame atomic absorption spectrometer (FAAS) has been improved. The analytes were complexed with 3-amino-7-dimethylamino-2-methylphenazine (Neutral Red, NR) and octylphenoxypolyethoxyethanol (Triton X-114)wasadded as a surfactant. The micellar solutionwasheated above 50 degrees C and loaded through a column packed with cotton for phase separation. Then the surfactant-rich phase was eluted using 0.05 mol L(-1) H2SO4 and the analytes were determined by FAAS. Chemical and flow variables influencing the instrumental and extraction conditions were optimized. Under optimized conditions for 25 mL of preconcentrated solution, the enrichment factors were 98 and 69, the limits of detection (3s) were 0.7 and 0.3 ng mL(-1), the limits of quantification (10s) were 2.2 and 1.0 ng mL(-1) for iron and copper, respectively. The relative standard deviation (RSD) for ten replicate measurements of 10 ng mL(-1) iron and copper were 2.1% and 1.8%, respectively. The proposed method was successfully applied to determination of iron and copper in spice samples. PMID:20627408

Sahin, Ci?dem Arpa; Tokgöz, Ilknur; Bekta?, Sema

2010-09-15

368

Determination of copper, lead and iron in water and food samples after column solid phase extraction using 1-phenylthiosemicarbazide on Dowex Optipore L-493 resin.  

PubMed

A novel solid phase extraction procedure for determination of copper, lead and iron in natural water and food samples has been established in the presented work. 1-Phenylthiosemicarbazide (1-PTSC) as ligand and Dowex Optipore L-493 resin as adsorbent were used in a mini chromatographic column. Various analytical conditions for the quantitative recoveries of analyte ions including pH, amounts of adsorbent, eluent, sample volume, etc. were investigated. The recovery values for analyte ions were higher than 95%. The determination of copper, lead and iron was performed by flame atomic absorption spectrometry. The influences of some alkali, alkali earth and transition metals on the recoveries of analyte ions were investigated. The preconcentration factor was 62.5. The limit of detections of the understudied analytes (k=3, N=21) were 0.64 ?g L(-1) for copper, 0.55 ?g L(-1) for lead and 0.82 ?g L(-1) for iron. The relative standard deviation was found to be lower than 6%. The accuracy of the method was confirmed with certified reference material (GBW 07605 Tea). The method was successively applied for the determination of copper, lead and iron in water and some food samples including cheese, bread, baby food, pekmez, honey, milk and red wine after microwave digestion. PMID:21111769

Yildiz, Ozden; Citak, Demirhan; Tuzen, Mustafa; Soylak, Mustafa

2011-02-01

369

Cadmium and iron-stress-inducible gene expression in the green alga Chlamydomonas reinhardtii : evidence for H43 protein function in iron assimilation  

Microsoft Academic Search

Early transcriptional responses of a cell wall-deficient mutant of the green alga Chlamydomonas reinhardtii to heavy-metal stress have been investigated using the method of mRNA differential display. We have identified, sequenced, and quantified the induction of a number of transcripts that are up-regulated by a brief (2-h) exposure to 25 µm cadmium chloride, including one transcript which is also highly

Peter Rubinelli; Surasak Siripornadulsil; Fei Gao-Rubinelli; Richard T. Sayre

2002-01-01

370

Calculation of binodals and spinodals in multicomponent alloys by different statistical methods with application to iron-copper-manganese alloys  

SciTech Connect

A generalization of the pair-cluster (PC) approximation in the theory of disordered systems to multicomponent alloys is proposed. It is shown that phase equilibrium boundaries (binodals) calculated in the mean-field (MF) approximation, which is used in standard calculations of phase diagrams by the CALPHAD method, coincide with the results of rigorous calculations for dilute alloys; however, the application of these methods to calculating the boundaries of the stability region with respect to the decomposition of an alloy (spinodals) leads to large errors. At the same time, in the PC approximation, the description of all statistical properties, including binodals and spinodals, turns out to be exact for dilute alloys. The methods developed are illustrated by an example of iron-copper-manganese ternary alloys.

Vaks, V. G., E-mail: vaks@mbslab.kiae.ru; Zhuravlev, I. A.; Khromov, K. Yu. [Russian Research Centre Kurchatov Institute (Russian Federation)

2010-11-15

371

Interactions of free copper (II) ions alone or in complex with iron (III) ions with erythrocytes of marine fish Dicentrarchus labrax.  

PubMed

As a consequence of human activity, various toxicants - especially metal ions - enter aquatic ecosystems and many fish are exposed to considerable levels. As the free ion and in some complexes, there is no doubt that copper promotes damage to cellular molecules and structures through radical formation. Therefore, we have investigated the influence of copper uptake by the red blood of the sea bass (Dicentrarchus labrax), and its oxidative action and effects on cells in the presence of complexed and uncomplexed Fe3+ ions. Erythrocytes were exposed to various concentrations of CuSO4, Fe(NO3)3, and K3Fe(CN)6 for up to 5h, and the effects of copper ions alone and in the combination with iron determined. The results show that inside the cells cupric ion interacts with hemoglobin, causing methemoglobin formation by direct electron transfer from heme Fe2+ to Cu2+. Potassium ferricyanide as a source of complexed iron decreases Met-Hb formation induced by copper ions unlike Fe(NO3)3. We also found that incubation of fish erythrocytes with copper increased hemolysis of cells. But complexed and uncomplexed iron protected the effect of copper. CuSO4 increased the level of lipid peroxidation and a protective effect on complexed iron was observed. Incubation of erythrocytes with copper ions resulted in the loss of a considerable part of thiol content at 10 and 20 microM. This effect was decreased by potassium ferricyanide and Fe(NO3)3 only after 1 and 3h of incubation. The level of nuclear DNA damage assayed by comet assay showed that 20 microM CuSO4 as well as 20 microM Fe(NO3)3 and 10 mM K3Fe(CN)6 induce single- and double-strand breaks. The lower changes were observed after the exposure of cells to K3Fe(CN)6. The data suggest that complexed iron can act protectively against copper ions in contrast to Fe(NO3)3. PMID:19524693

Labieniec, Magdalena; Milowska, Katarzyna; Balcerczyk, Aneta; Rucinska, Agata; Sadowska, Magdalena; Jokiel, Marta; Brichon, Gerard; Gabryelak, Teresa

2009-09-01

372

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

PubMed

Cucumber plants grown in hydroponics containing 10 ?M Cd(II), Ni(II) and Pb(II), and iron supplied as Fe(III) EDTA or Fe(III) citrate in identical concentrations, were investigated by total-reflection X-ray fluorescence spectrometry with special emphasis on the determination of iron accumulation and distribution within the different plant compartments (root, stem, cotyledon and leaves). The extent of Cd, Ni and Pb accumulation and distribution were also determined. Generally, iron and heavy-metal contaminant accumulation was higher when Fe(III) citrate was used. The accumulation of nickel and lead was higher by about 20% and 100%, respectively, if the iron supply was Fe(III) citrate. The accumulation of Cd was similar. In the case of Fe(III) citrate, the total amounts of Fe taken up were similar in the control and heavy-metal-treated plants (27-31 ?mol/plant). Further, the amounts of iron transported from the root towards the shoot of the control, lead- and nickel-contaminated plants were independent of the iron(III) form. Although Fe mobility could be characterized as being low, its distribution within the shoot was not significantly affected by the heavy metals investigated. PMID:21342715

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

2011-07-01

373

Leaching of cadmium, chromium, copper, lead, and zinc from two slag dumps with different environmental exposure periods under dynamic acidic condition.  

PubMed

Over the past few decades, zinc smelting activities in Guizhou, China have produced numerous slag dumps, which are often dispersed on roadsides and hill slopes throughout the region. During periods of acid rain, these exposed slags release heavy metals into surface water bodies. A column leaching study was designed to test the potential release of the heavy metals cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), and zinc (Zn) under simulated acid rain events. Two slags with varying environmental exposure periods were packed in columns and subjected to leaching solutions of pH 3.5, 5.5, or DI H2O at intervals of 1, 7, 14, 28, 56d. Pulse concentrations of Cd in leachate were found above 5?g/L, Cr, Pb, and Zn >10?g/L, whereas, Cu reached 10?g/L. After five leaching events, the leachability (percentage of cumulative heavy metal leached after five leaching events as in its respective total concentration in slags) of Cd was 0.05 percent and 0.035 percent from the old and young slag, respectively. Cr (0.035 percent and 0.05 percent) was greater than Cu (0.002 percent and 0.005 percent) and Zn (0.006 percent and 0.003 percent), while the lowest leachability was observed for Pb (0.0005 percent and 0.0002 percent) from the old and young slags, respectively. Reaction rates (release amount of heavy metals in certain period of leaching) of heavy metals in the leachates demonstrated the sequence of Zn>Cr>Cd, Cu>Pb. Leaching release of heavy metals was jointly affected by the pH of leaching solution and mineral composition of slags (including chemical forms of Cd, Cr, Cu, Pb, and Zn). Environmental exposure period of slags, resulting in the alteration of minerals, could affect the release process of heavy metals in leaching as well. PMID:24632122

Jin, Zhisheng; Liu, Taoze; Yang, Yuangen; Jackson, Daniel

2014-06-01

374

Effects of copper and cadmium on ion transport and gill metal binding in the Amazonian teleost tambaqui (Colossoma macropomum) in extremely soft water.  

PubMed

Metal toxicity in fish is expected to be most severe in soft waters because of the low availability of cations (particularly Ca(2+)) to out-compete the metal forms for binding sites on the gills. Natural waters in the Amazon basin are typically soft due to regional geochemistry, but few studies have focused on metal toxicity in fish native to the basin. We assessed the ionoregulatory effects of waterborne copper (Cu) and cadmium (Cd) on tambaqui (Colossoma macropomum) in extremely soft water (10 micromoll(-1) Ca(2+)). Tambaqui had a very high tolerance to Cu (50-400 microgl(-1)), as indicated by a complete lack of inhibition of Na(+) uptake and an ability to gradually recover over 6h from elevated diffusive Na(+) losses caused by Cu. The insensitivity of active Na(+) influx to Cu further supports the notion that Amazonian fish may have a unique Na(+) transport system. Addition of 5-10 mgCl(-1) of dissolved organic matter (DOM) did not prevent initial (0-3h) negative Na(+) balance in tambaqui exposed to Cu. Exposure to 40 mgCl(-1) DOM prevented Na(+) losses in tambaqui even at 400 microgl(-1) Cu, probably because most Cu was complexed to DOM. Tambaqui exposed to waterborne Cd (10-80 microgl(-1)) experienced an average of 42% inhibition in whole body Ca(2+) uptake relative to controls within 3h of exposure to the metal. Inhibition of Ca(2+) uptake increased over time and, at 24h, Ca(2+) uptake was suppressed by 51% and 91% in fish exposed to 10 and 80 microgl(-1) Cd, respectively. Previous acclimation of fish to either elevated [Ca(2+)] or elevated [DOM] proved to be very effective in protecting against acute short-term metal accumulation at the gills of tambaqui in soft water (in the absence of the protective agent during metal exposure), suggesting a conditioning effect on gill metal binding physiology. PMID:16051381

Matsuo, Aline Y O; Wood, Chris M; Val, Adalberto L

2005-09-30

375

Biochemical responses of juvenile European sturgeon, (Huso huso) to a sub-lethal level of copper and cadmium in freshwater and brackish water environments.  

PubMed

In Caspian Sea basin, sturgeons spend the larval and juvenile stages in freshwaters of rivers and then, they migrate to brackish waters of the sea where they grow and mature. With regard to the elevation of the metal concentrations in coastal waters and sediments of the Caspian Sea and its adjacent rivers, it is likely that juvenile sturgeon are exposed to sub-lethal levels of metals during seawater entry process. We compared the biochemical responses of juvenile European sturgeon, (Beluga, Huso huso) exposed to a sub-lethal level of copper (Cu, 20 ?g/L) and cadmium (Cd, 300 ?g/L) in freshwater (FW, 0 ppt) and brackish water (BW, 11 ppt) for seven days. The results showed that the levels of plasma glucose increased significantly in BW and in all metal exposed groups. Also, plasma cortisol concentrations showed significant increases when juveniles were exposed to BW, Cu(FW/BW) and Cd(BW). The activity of liver superoxide dismutase (SOD) decreased significantly in BW compared with FW. Moreover, Cu and Cd exposure enhanced the activity of SOD in BW, while SOD did not show any changes in FW. The levels of tissue and plasma proteins as well as plasma triiodothyronine (T3), thyroxine (T4) and liver Catalase (CAT) activity remained constant when animals were exposed to Cu/Cd in both FW and BW environments. Our data indicate that exposure of juvenile beluga to BW stimulated the general biochemical responses of stress such as cortisol and glucose, while sub-lethal exposure to Cu and Cd caused oxidative stress in BW environment but not in FW. PMID:24499513

Zahedi, Saeed; Akbarzadeh, Arash; Rafati, Maryam; Banaee, Mahdi; Sepehri Moghadam, Heshmat; Raeici, Hadi

2013-01-01

376

Canadian House Dust Study: population-based concentrations, loads and loading rates of arsenic, cadmium, chromium, copper, nickel, lead, and zinc inside urban homes.  

PubMed

The Canadian House Dust Study was designed to obtain nationally representative urban house dust metal concentrations (?g g(-1)) and metal loadings (?g m(-2)) for arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn). Consistent sampling of active dust of known age and provenance (area sampled) also permitted the calculation of indoor loading rates (mg m(-2) day(-1) for dust and ?g m(-2) day(-1) for metals) for the winter season (from 2007 to 2010) when houses are most tightly sealed. Geomean/median indoor dust loading rates in homes located more than 2 km away from industry of any kind (9.6/9.1 mg m(-2) day(-1); n=580) were significantly lower (p<.001) than geomean (median) dust loading rates in homes located within 2 km of industry (13.5/13.4 mg m(-2) day(-1); n=421). Proximity to industry was characterized by higher indoor metal loading rates (p<.003), but no difference in dust metal concentrations (.29?p?.97). Comparisons of non-smokers' and smokers' homes in non-industrial zones showed higher metal loading rates (.005?p?.038) in smokers' homes, but no difference in dust metal concentrations (.15?p?.97). Relationships between house age and dust metal concentrations were significant for Pb, Cd and Zn (p<.001) but not for the other four metals (.14?p?.87). All seven metals, however, displayed a significant increase in metal loading rates with house age (p<.001) due to the influence of higher dust loading rates in older homes (p<.001). Relationships between three measures of metals in house dust - concentration, load, and loading rate - in the context of house age, smoking behavior and urban setting consistently show that concentration data is a useful indicator of the presence of metal sources in the home, whereas dust mass is the overriding influence on metal loadings and loading rates. PMID:23220142

Rasmussen, Pat E; Levesque, Christine; Chénier, Marc; Gardner, H David; Jones-Otazo, Heather; Petrovic, Sanya

2013-01-15

377

Bioaccumulation and Tissue Distribution of Arsenic, Cadmium, Copper and Zinc in Crassostrea virginica Grown at Two Different Depths in Jamaica Bay, New York  

PubMed Central

Historically, Jamaica Bay was a site of extensive oyster beds and shellfish culture leases that supported a significant oyster fishery in the New York area. The industrial and urban expansion of the early 1900’s led to over-harvesting and a deterioration in water and bay sediment quality that coincided with shellfish decline and the ultimate disappearance of oysters from the bay. Over the past 50 years, efforts to arrest and reverse the pollution problems of Jamaica Bay have been undertaken but the area still contains metals and other pollutants at levels higher than NYS Water Quality Standards. Previous we showed that Crassostrea virginica seed transplanted to the bay had excellent growth and survival despite the bay’s pollution problems. In this study we measured the one-year bioaccumulation and tissue distribution of four metals in C. virginica seed that were transplanted to the bay at two different depths: one foot from the surface and one foot above the sediment. Tissues of C. virginica were dissected, dried and digested in nitric acid. Arsenic, cadmium, copper and zinc levels were measured using electrothermal vaporization with deuterium lamp background correction in an atomic absorption spectrophotometer fitted with a THGA graphite furnace. Metals were distributed in the various tissues in ?g/g dry weight amounts, which correlate well with published values for whole oysters grown in other polluted areas. Metal distributions were not homogeneous throughout the animals and in most of the tissues tested, oysters grown near the surface accumulated more metal than those positioned near bay sediment.

Rodney, Eric; Herrera, Pedro; Luxama, Juan; Boykin, Mark; Crawford, Alisa; Carroll, Margaret A.; Catapane, Edward J.

2011-01-01

378

Copper and cadmium effects on growth and extracellular exudation of the marine toxic dinoflagellate Alexandrium catenella: 3D-fluorescence spectroscopy approach.  

PubMed

In this study, metal contamination experiments were conducted to investigate the effects of copper and cadmium on the growth of the marine toxic dinoflagellate Alexandrium catenella and on the production of dissolved organic matter (Dissolved Organic Carbon: DOC; Fluorescent Dissolved Organic Matter: FDOM). This species was exposed to increasing concentrations of Cu(2+) (9.93 × 10(-10)-1.00 × 10(-7)M) or Cd(2+) (1.30 × 10(-8)-4.38 × 10(-7)M), to simulate polluted environments. The drastic effects were observed at pCu(2+)=7.96 (Cu(2+): 1.08 × 10(-8)M) and pCd(2+)=7.28 (Cd(2+): 5.19 × 10(-8)M), where cyst formation occurred. Lower levels of Cu(2+) (pCu(2+)>9.00) and Cd(2+) (pCd(2+)>7.28) had no effect on growth. However, when levels of Cu(2+) and Cd(2+) were beyond 10(-7)M, the growth was totally inhibited. The DOC released per cell (DOC/Cell) was different depending on the exposure time and the metal contamination, with higher DOC/Cell values in response to Cu(2+) and Cd(2+), comparatively to the control. Samples were also analyzed by 3D-fluorescence spectroscopy, using the Parallel Factor Analysis (PARAFAC) algorithm to characterize the FDOM. The PARAFAC analytical treatment revealed four components (C1, C2, C3 and C4) that could be associated with two contributions: one, related to the biological activity; the other, linked to the decomposition of organic matter. The C1 component combined a tryptophan peak and a characteristic humic substances response, and the C2 component was considered as a tryptophan protein fluorophore. The C3 and C4 components were associated to marine organic matter production. PMID:23928326

Herzi, Faouzi; Jean, Natacha; Zhao, Huiyu; Mounier, Stéphane; Mabrouk, Hassine Hadj; Hlaili, Asma Sakka

2013-10-01

379

Development of a water-effect ratio for copper, cadmium, and lead for the Great Works River in Maine using Ceriodaphnia dubia and Salvelinus fontinalis  

SciTech Connect

The control of chemicals discharged to suface waters of the United States is an important objective of the National Pollutant Discharge Elimination System (NPDES) as specified by the Clean Water Act. The U.S. Environmental Protection Agency (EPA) recommends a combination of chemical-specific and whole-effluent toxicity limits in NPDES permits to accomplish this objective. The requirements for toxicity testing and whole effluent toxicity limitations in NPDES permits are based on the narrative toxicity water quality standards, and, in some cases, numerical toxicity standards present in EPA regulations. Because national water quality criteria were developed to protect the biological integrity of all surface waters in the US, they may require modification for site-specific applications. As an alternative to national criteria, site-specific criteria can be tailored specifically to the local ecosystem. Site-specific factors like chemical quality of receiving water, flow, temperature and species composition play a major role in developing alternative discharge limits. The hazard posed by a chemical when released to wastewater and consequently to a receiving system is a function of concentration, bioavailability and influence of site conditions. The site-specific evaluation of toxicity of a chemical combines a knowledge of the properties which influence the behavior of a chemical such as partitioning, chelation, speciation, adsorption to solids, and interaction with other chemicals present in the matrix and an understanding of the toxicity of the chemical and its potential for bioaccumulation. The primary objective of this study was to develop water effect-ratios for cadmium, copper and lead which can be used to derive site-specific water quality criteria for process water discharged from a metal finishing plant. 9 refs., 3 tabs.

Jop, K.M.; Askew, A.M.; Foster, R.B. [Springborn Labs., Wareham, MA (United States)

1995-01-01

380

The determination of aluminum, copper, iron, and lead in glycol formulations by atomic absorption spectroscopy  

NASA Technical Reports Server (NTRS)

Initial screening tests and the results obtained in developing procedures to determine Al, Cu, Fe, and Pb in glycol formulations are described. Atomic absorption completion was selected for Cu, Fe and Pb, and after comparison with emission spectroscopy, was selected for Al also. Before completion, carbon, iron, and lead are extracted with diethyl dithio carbamate (DDC) into methyl isobutyl ketone (MIBK). Aluminum was also extracted into MIBK using 8-hydroxyquinoline as a chelating agent. As little as 0.02 mg/l carbon and 0.06 mg/l lead or iron may be determined in glycol formulations. As little as 0.3 mg/l aluminum may be determined.

1977-01-01

381

Ferric iron uptake genes are differentially expressed in the presence of copper sulfides in Acidithiobacillus ferrooxidans strain LR.  

PubMed

Acidithiobacillus ferrooxidans is one of the most widely used microorganisms in bioleaching operations to recover copper from low-grade copper sulfide ores. This work aimed to investigate the relative expression of genes related to the iron uptake system when A. ferrooxidans LR was maintained in contact with chalcopyrite or bornite as the sole energy source. Real-time quantitative PCR analysis revealed that the presence of bornite had no effect on the expression of seven genes related to the siderophore-mediated Fe(III) uptake system, while in the presence of chalcopyrite the expression of the genes was up-regulated. Bioinformatic analysis of the genomic region where these genes were found revealed the existence of three new putative DNA-binding sequences for the ferric iron uptake transcriptional regulator (Fur). Electrophoretic mobility shift assays demonstrated that a purified A. ferrooxidans His-tagged Fur protein was able to bind in vitro to each of these putative Fur boxes, suggesting that Fur regulated the expression of these genes. The expression of fur and two known Fur-regulated genes, mntH and dsrK, was also investigated in the presence of chalcopyrite. While the expression of fur and mntH was up-regulated, the expression of dsrK was down-regulated. The low amount of ferrous iron in the medium was probably responsible for the up-regulation of fur and the genes related to the siderophore-mediated Fe(III) uptake system when A. ferrooxidans LR was kept in the presence of chalcopyrite. A homology model of the A. ferrooxidans Fur was constructed and revealed that the putative DNA-binding surface presents conserved positively charged residues, supporting a previously suggested mode of interaction with DNA. The up-regulation of fur and the siderophore-mediated Fe(III) uptake genes, and the down-regulation of dsrK suggest that in the presence of chalcopyrite Fur acts as a transcription inducer and repressor. PMID:21132364

Ferraz, Lúcio F C; Verde, Leandro C L; Vicentini, Renato; Felício, Ana P; Ribeiro, Marcelo L; Alexandrino, Fabiana; Novo, Maria T M; Garcia, Oswaldo; Rigden, Daniel J; Ottoboni, Laura M M

2011-03-01

382

Laser-initiated combustion studies of selected aluminum, copper, iron, and nickel alloys  

NASA Technical Reports Server (NTRS)

The results of combustion studies at atmospheric pressure on ten metal alloys are presented. The alloys studied were aluminum alloys 1100, 2219, 6061, and tensile-50; 304, 347 and 21-6-9 stainless steel; inconel 600; beryllium copper and a bronze. It was found that once ignition was achieved all alloys would generally burn to completion. The overall combustion process appears to obey a first order rate process. Preliminary conclusions are presented along with recommendations for future work.

Bransford, J. W.; Clark, A. F.

1981-01-01

383

Recovering iron, manganese, copper, cobalt, and high-purity nickel from sea nodules  

NASA Astrophysics Data System (ADS)

Many studies have investigated methods of recovering valuable metals from sea nodules. Recently, a research group in Japan developed a smelting and chlorine process after investigating a variety of existing processes and comparing their respective efficiencies with the same nodules. The best results were obtained by combining pyrometallurgical and hydrometallurgical treatments, which enabled the efficient recovery of manganese, nickel, copper, and cobalt. High-purity nickel can be also produced through further solvent extraction.

Kohga, Tetsuyoshi; Imamura, Masaki; Takahashi, Junichi; Tanaka, Nobuhiro; Nishizawa, Tokuo

1995-12-01

384

Composition and Atomic Structure of Two Ordering Binary-Alloy Surfaces: COPPER(3)GOLD(110) and IRON(TIN)(100)  

NASA Astrophysics Data System (ADS)

The composition and atomic structure of the top two layers of the Cu_3Au(110) surface were studied as a function of temperature to understand segregation in a model ordered alloy. A combination of Auger electron spectroscopy, low-energy electron diffraction, low-energy ion scattering, and molecular statics calculations with many-body potentials, revealed behavior that was different from the previously-investigated Cu_3Au(100) surface. The pattern of planes consisting of equal parts copper and gold, alternating with planes of pure copper, was found to be disrupted at the (110) surface. The bulk was terminated at a Cu-Au layer, which had a slight depletion of gold (45%) at room temperature. The second layer, nominally a pure copper plane, contained a substantial amount of gold (25%). The top two surface layers each reached 35% gold below the bulk ordering temperature of 390 ^circC. The differences between the (110) and the (100) surfaces were ascribed to differences in the "effective" coordination number of first-layer atoms. When annealed below 150^circC, the (110) surface was found to be reconstructed, with every other copper (001) row removed from the surface. The newly -exposed second-layer lattice sites were found to be occupied preferentially by gold. Surface-stress-tensor arguments are used to describe the origin of this reconstruction. Iron crystals doped with tin are known to exhibit segregation of more than one monolayer of tin to the (100) surface. This unusually large coverage raises the question of whether the multilayer enrichment is due to equilibrium segregation or to some kind of metastable precipitation phenomenon. In the latter case, the presence of the equilibrium bulk second phase, FeSn, would be expected to cause a reduction in the surrounding tin coverage. This issue was addressed by the use of chemical-vapor deposition to seed the surface of a tin-doped crystal with FeSn. It was found that the presence of this second phase did not alter the equilibrium surface coverage, which returned quickly to its previous level by surface diffusion from the FeSn crystallites.

Wallace, William Edward, III

385

Wear mechanism of copper alloy wire sliding against iron-base strip under electric current  

Microsoft Academic Search

In electric railways, the wear rate of trolley wire decides the life of the wire. In order to search for methods of decreasing the wear rate. laboratory wear test was carried out with three types of wire materials sliding against an iron-base sintered alloy strip under electric current flow condition. The test results indicate that the wear rate of wire

Hiroki Nagasawa; Koji Kato

1998-01-01

386

First-principles pseudopotential study of structures of iron on copper ( 001) surface  

Microsoft Academic Search

An ab initio pseudopotential density functional study of iron on Cu(001) surfaces is presented. No surface relaxation is found on clean Cu(001) surface, while small first layer expansions are found for both the monolayer and double layer Fe coverage. The total energies of various surfaces are calculated and compared. It is concluded that a proposed bilayer growth mode is not

X. W. Wang

1995-01-01

387

Structure and properties of clusters of self-interstitial atoms in fcc copper and bcc iron  

Microsoft Academic Search

Static and molecular dynamics simulations have been used with different types of interatomic potentials to investigate the structure, properties and stability of self-interstitial atom (SIA) clusters produced during irradiation. In f-iron (Fe), faulted clusters of dumbbells are unstable for all the potentials. The most stable SIA clusters are sets of parallel crowdions. Large clusters of this type form perfect dislocation

Yu. N. Osetsky; A. Serra; B. N. Singh; S. I. Golubov

2000-01-01

388

Structure and properties of clusters of self-interstitial atoms in fcc copper and bcc iron  

Microsoft Academic Search

Static and molecular dynamics simulations have been used with different types of interatomic potentials to investigate the structure, properties and stability of self-interstitial atom (SIA) clusters produced during irradiation. In ?-iron (Fe), faulted clusters of <110> dumbbells are unstable for all the potentials. The most stable SIA clusters are sets of parallel <111> crowdions. Large clusters of this type form

Yu. N. Osetsky; A. Serra; B. N. Singh; S. I. Golubov

2000-01-01

389

Solubilization of Cu 2+ from copper ore by iron-oxidizing bacteria isolated from the natural environment and identification of the enzyme that determines Cu 2+ solubilization activity  

Microsoft Academic Search

Solubilization of Cu2+ from copper concentrate by 67 strains of iron-oxidizing bacteria isolated from the natural environment was studied. In the case of static growth on copper concentrate (5%)-salt medium (pH 2.5) at 30°C, Cu2+ solubilization activities of 65 strains including Thiobacillus ferrooxidans strains AP19-3, OK-2, OK-3, OK1–50, Funis and NASF-1 ranged from 2.5–3.5 mg Cu2+\\/ml\\/33 d. In contrast, the

Tsuyoshi Sugio; Fauzia Akhter

1996-01-01

390

Rosette iron deficiency transcript and microRNA profiling reveals links between copper and iron homeostasis in Arabidopsis thaliana  

PubMed Central

Iron (Fe) is an essential plant micronutrient, and its deficiency limits plant growth and development on alkaline soils. Under Fe deficiency, plant responses include up-regulation of genes involved in Fe uptake from the soil. However, little is known about shoot responses to Fe deficiency. Using microarrays to probe gene expression in Kas-1 and Tsu-1 ecotypes of Arabidopsis thaliana, and comparison with existing Col-0 data, revealed conserved rosette gene expression responses to Fe deficiency. Fe-regulated genes included known metal homeostasis-related genes, and a number of genes of unknown function. Several genes responded to Fe deficiency in both roots and rosettes. Fe deficiency led to up-regulation of Cu,Zn superoxide dismutase (SOD) genes CSD1 and CSD2, and down-regulation of FeSOD genes FSD1 and FSD2. Eight microRNAs were found to respond to Fe deficiency. Three of these (miR397a, miR398a, and miR398b/c) are known to regulate transcripts of Cu-containing proteins, and were down-regulated by Fe deficiency, suggesting that they could be involved in plant adaptation to Fe limitation. Indeed, Fe deficiency led to accumulation of Cu in rosettes, prior to any detectable decrease in Fe concentration. ccs1 mutants that lack functional Cu,ZnSOD proteins were prone to greater oxidative stress under Fe deficiency, indicating that increased Cu concentration under Fe limitation has an important role in oxidative stress prevention. The present results show that Cu accumulation, microRNA regulation, and associated differential expression of Fe and CuSOD genes are coordinated responses to Fe limitation.

Waters, Brian M.; Stein, Ricardo J.

2012-01-01

391

Iron Absorption by Infants.  

National Technical Information Service (NTIS)

The research team studied absorption of iron from carefully selected iron-fortified foods that are now commercially available or are attractive candidates for future iron fortification. Because of possible adverse interactions with zinc and copper when in...

S. J. Fomon

1995-01-01

392

Zinc, cadmium, and copper mobility and accumulation in reeds (Phragmites australis) in urban sediments from two stormwater infiltration basins  

NASA Astrophysics Data System (ADS)

Infiltration basins are stormwater management techniques that are widely used to reduce stormwater volume. The settling of stormwater particles leads to a contaminated sediment layer at the basin surface. Phragmites australis used in constructed wetlands are widely present in infiltration basins. Such plant can play a role on the fate of heavy metals either directly by their uptake or indirectly by modification of physico-chemical characteristics of the sediment. The aim of this study is to assess Zn, Cd and Cu potential mobility and their bioaccumulation by reeds during plant's growth in urban sediments offering two different geochemical contexts. Methodology is based on the monitoring (in june, august and december) of physico-chemical characteristics of sediment deposit in two basins. These basins, "Minerve" and "Grézieu", located on both sides of Lyon city are characteristic of two different geochemical context. "Minerve" is in the east and "Grézieu" in the west part. The geology of the eastern part of Lyon is characterized by carbonated fluvio-glacial deposits. In the western part, the subsoil is mainly composed of gneiss and granit. Moreover, 20 cm of gravel and a sand layer were initially added at the surface of the "Grézieu" basin. In "Minerve", a clay material was initially added and a filter trench was built along the basin to allow water infiltration. We characterized the sediment deposit by the identification of their geochemical characteristics (Zn, Cu, Cd, total content, pH, CEC, C/N, carbonates and major elements contents …). Then we studied the potential mobility of the three metals by single chemical extraction (CaCl2 for the exchangeable phase, acetate buffer for the acido-soluble phase and diethylenetriamine-pentaacetic acid (DTPA) for the fraction associated to the organic matter). The accumulation of Zn, Cd and Cu in aerial parts and roots of the reeds was also measured. The results show clearly that "Grézieu" sediment is more enriched in organic matter and metals than "Minerve". For example, Zn contents are equal to 400 mg/kgDW in "Grézieu" whereas it is equal to 80 mg/kgDW in "Minerve". In the most contaminated basin "Grézieu", metals mobility is mainly controlled by their association with carbonates and organic matter. Thus, copper associated with organic matter may represent almost 70% of the total copper content. In the "Minerve" sediment, the metals are distributed on the different sediment components, with very stable associations on the different mineral phases. The reed accumulates more metal in the context of the most contaminated basin (Grézieu), but without any differences in bioconcentration factors. The high metal contents in "Grézieu" sediments limited also the growth of reed. Moreover, for "Grézieu" sediment, characteristics evolve with the seasons. Thus, texture decreases from June to December in parallel with an increase in organic matter and metals in the sediment deposit.

Bedell, J.-P.; Saulais, S.; Delolme, C.

2012-04-01

393

Photovoltaic properties of a heterojunction based on copper phthalocyanine films on the surface of polycrystalline cadmium sulfide  

NASA Astrophysics Data System (ADS)

The photovoltaic effect has been detected and studied in thin-film structures based on thermally deposited 200-nm-thick copper phthalocyanine (CuPc) films on the surface of polycrystalline CdS. The structures under study demonstrate the linear current-voltage characteristics at external electric fields to 3.5 × 104 V/cm. Two components of the photovoltage of different signs have been revealed when the sample is illuminated in the wavelength range from 350 to 700 nm. The first component has the positive sign on the CuPc film side and is observed when using the radiation with a wavelength lesser than 500 nm, i.e., in conditions of predominant absorption of the radiation in the CdS layer. The second component has the negative sign on the CuPc film side and is observed when using the radiation with a wavelength in the range from 500 to 570 nm, corresponding to the spectral region of the absorption edge of the CuPc films. The dependences of the photovoltage on the radiation intensity studied in the range from 5 × 1012 to 1014 photons cm-2 s-1 are different in the cases of the two detected components. Mechanisms of generation of the photovoltage components associated with a change in the band bending during photogeneration of charge carriers in the region of space charge in CdS and a change in conditions of the charge transfer in the interfacial CuPc/CdS region during the radiation absorption in the CuPc film have been proposed.

Komolov, A. S.; Lazneva, E. F.; Chepilko, N. S.; Gerasimova, N. B.

2013-07-01

394

Abundant, seasonally variable supply of glacier flour-derived iron drives high nitrate consumption in Copper River plume and adjacent Gulf of Alaska continental shelf  

NASA Astrophysics Data System (ADS)

Recent work has suggested that high iron supply may contribute to a northward increase in phytoplankton biomass along the U.S. west coast, consistent with “bottom-up” control of these coastal ecosystems. We examine this hypothesis in waters of the Copper River plume and nearby continental shelf in the northern Gulf of Alaska (GoA). These are the first data we know of examining “bottom up” control of this coastal ecosystem by the supply of nitrate and iron. These are also the first data we know of that examine seasonal variability in the mechanisms that supply iron to this region, and in the iron concentrations. High concentrations (several hundred nM) of “total dissolveable” Fe (unfiltered, pH ~2) were present in surface waters spanning the continental shelf in early April 2010, from resuspension of fine glacial flour. Concentrations decreased dramatically beyond the shelf break. This fine particulate matter represents a large source of “dissolved” Fe to these waters. Surface-water nitrate concentrations were fairly uniform (~15 uM) across the entire shelf at this time, due to deep winter mixing. By late July this shelf particulate Fe source is greatly diminished, owing to strong stratification. Yet there is abundant “total dissolveable” Fe (several mM) at this time from the Copper River plume (largest single freshwater source to the GoA) and lower (several hundred nM) concentrations in the AK coastal current (that reflect the cumulative impact of melting glaciers from further south). By late July this abundant supply of iron in the Copper River vicinity, together with strong stratification, lead to complete consumption of surface-water nitrate across the entire shelf (and extending tens of km beyond the shelf). These data are consistent with the idea that high primary productivity in this region is fueled by abundant wintertime surface-water nitrate, together with iron supply from fine, labile, glacier-derived particulate matter from seasonally variable sources.

Crusius, J.; Schroth, A. W.; Campbell, R. W.; Nielsen, J. L.; Hoyer, I. R.; Brooks, W.

2010-12-01

395

Disruption of Metallothionein Expression with Antisense Oligonucleotides Abolishes Protection Against Cadmium Cytotoxicity in Molluscan Hemocytes  

Microsoft Academic Search

The relationship between metallothionein (MT) induction and cytotoxicity was examined in isolated oyster hemocytes exposed in vitro to cadmium, copper, and zinc. In all cases MT induction increased to peak levels with increased metal dose, then declined with continued increases in dose. The effectiveness of these metals as inducers of MT was cadmium > copper > zinc, with cadmium the

R. A. Butler; G. Roesijadi

2001-01-01

396

Elevated copper in the amyloid plaques and iron in the cortex are observed in mouse models of Alzheimer's disease that exhibit neurodegeneration  

PubMed Central

BACKGROUND In Alzheimer’s disease (AD), alterations in metal homeostasis, including the accumulation of metal ions in the plaques and an increase of iron in the cortex, have been well documented but the mechanisms involved are poorly understood. OBJECTIVE In this study, we compared the metal content in the plaques and the iron speciation in the cortex of three mouse models, two of which show neurodegeneration (5xFAD and Tg-SwDI/NOS2?/? (CVN) and one that shows very little neurodegeneration (PSAPP). METHODS The Fe, Cu, and Zn contents and speciation were determined using synchrotron X-ray fluorescence microscopy (XFM) and X-ray absorption spectroscopy (XAS), respectively. RESULTS In the mouse models with reported significant neurodegeneration, we found that plaques contained ~25% more copper compared to the PSAPP mice. The iron content in the cortex increased at the late stage of the disease in all mouse models, but iron speciation remains unchanged. CONCLUSIONS The elevation of copper in the plaques and iron in the cortex is associated with AD severity, suggesting that these redox-active metal ions may be inducing oxidative damage and directly influencing neurodegeneration.

Bourassa, Megan W.; Leskovjan, Andreana C.; Tappero, Ryan V.; Farquhar, Erik R.; Colton, Carol A.; Van Nostrand, William E.; Miller, Lisa M.

2014-01-01

397

Comparison of Open Tubular Cadmium Reactor and Packed Cadmium Column in Automated Gas-Segmented Continuous Flow Nitrate Analysis  

Microsoft Academic Search

Detailed procedures are provided for preparing packed cadmium columns to reduce nitrate to nitrite. Experiments demonstrated the importance of conditioning both open tubular cadmium reactor (OTCR) and packed copper-coated cadmium columns to achieve 100% reduction efficiency. The effects of segmentation bubbles in the OTCR upon reduction efficiency and baseline noise in nitrate analysis are investigated using an auto-analyzer. Metal particles

Jia-Zhong Zhang; Charles J. Fischer; Peter B. Ortner

2000-01-01

398

Modulation of copper toxicity-induced oxidative damage by excess supply of iron in maize plants  

Microsoft Academic Search

In this study, we examined the modulation of Cu toxicity-induced oxidative stress by excess supply of iron in Zea mays L. plants. Plants receiving excess of Cu (100 ?M) showed decreased water potential and simultaneously showed wilting in the\\u000a leaves. Later, the young leaves exhibited chlorosis and necrotic scorching of lamina. Excess of Cu suppressed growth, decreased\\u000a concentration of chloroplastic pigments

Praveen Kumar; Rajesh Kumar Tewari; Parma Nand Sharma

2008-01-01

399

Leaching of iron and toxic heavy metals from anaerobically-digested sewage sludge  

Microsoft Academic Search

Summary Heavy metal-loaded sewage sludge was leached abiotically using FeCl2 and FeCl3 which are applied in waste water treatment plants to eliminate phosphate and for coagulation. Due to the hydrolyzing nature of ferric iron, ferric chloride (100 mmll L-1) was able to solubilize more than 90% of copper and zinc and more than 80% of cadmium, with an optimal pulp

Hermann Strasser; Herbert Brunner; Franz Schinner

1995-01-01

400

Removal and preconcentration of lead (II), copper (II), chromium (III) and iron (III) from wastewaters by surface developed alumina adsorbents with immobilized 1-nitroso-2-naphthol  

Microsoft Academic Search

The potential removal and preconcentration of lead (II), copper (II), chromium (III) and iron (III) from wastewaters were investigated and explored. Three new alumina adsorbents of acidic, neutral and basic nature (I–III) were synthesized via physical adsorption and surface loading of 1-nitroso-2-naphthol as a possible chelating ion-exchanger. The modified alumina adsorbents are characterized by strong thermal stability as well as

Mohamed E. Mahmoud; Maher M. Osman; Osama F. Hafez; Essam Elmelegy

2010-01-01

401

Welding procedure specification: gas tungsten arc welding of nickel-copper to nickel-chromium-iron. Supplement 1. Records of procedure qualification tests  

SciTech Connect

Procedure WPS-2303-ASME-3 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc welding of nickel-copper N04400 (P-42) to nickel-chromium-iron N06600 (P-43), in thickness range of 0.035 to 0.432 inch; filler metal is ERNiCu-7 (F-42); shielding gas is argon.

Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

1986-06-01

402

Determination of Copper, Iron, Nickel, and Zinc in Ethanol Fuel by Flame Atomic Absorption Spectrometry Using On?Line Preconcentration System  

Microsoft Academic Search

In this work, an on?line system for preconcentration and determination of copper, iron, nickel, and zinc at µg L level by flame atomic absorption spectrometry (FAAS) has been developed. Amberlite XAD?4 functionalized with 3,4?dihydroxybenzoic acid packed in a minicolumn was used as metal sorbent. The retained metals can be quickly eluted from sorbent material, with the eluent stream consisting of hydrochloric

Leonardo S. G. Teixeira; Marcos de A. Bezerra; Valfredo A. Lemos; Hilda C. dos Santos; Djane S. de Jesus; Antônio C. S. Costa

2005-01-01

403

Distribution of Copper, Iron, and Zinc in Biological Samples (Scalp Hair, Serum, Blood, and Urine) of Pakistani Viral Hepatitis (A–E) Patients and Controls  

Microsoft Academic Search

The aim of the present study was to compare the level of copper (Cu), iron (Fe) and zinc (Zn) in biological samples (serum,\\u000a blood, urine, and scalp hair) of patients suffering from different viral hepatitis (A, B, C, D, and E; n?=?521) of both gender age ranged 31–45 years. For comparative study, 255 age-matched control subjects, of both genders residing\\u000a in

Nida Fatima Kolachi; Tasneem Gul Kazi; Hassan Imran Afridi; Naveed Kazi; Ghulam Abbas Kandhro; Abdul Qadir Shah; Jameel Ahmed Baig; Sham Kumar Wadhwa; Sumaira Khan; Faheem Shah; Mohammad Khan Jamali; Mohammad Balal Arain

404

Effect of Dietary Calcium and Phosphorus Levels on the Utilization of Iron, Copper, and Zinc by Adult Males1-2  

Microsoft Academic Search

Iron, copper, and zinc utilization were examined in nine adult males fed a moderate calcium-moderate phosphorus diet (MCaMP), a moderate calcium-high phosphorus diet (MCaHP), and a high calcium-high phosphorus diet (HCaHP) during a 39-day balance study. The moderate and high calcium diets contained 780 mg and 2382 mg calcium daily, respectively. The moderate and high phosphorus diets contained 843 and

SUZANNE M. SNEDEKER; J. L. GREGER

405

Determination of copper, lead and iron in water and food samples after column solid phase extraction using 1-phenylthiosemicarbazide on Dowex Optipore L-493 resin  

Microsoft Academic Search

A novel solid phase extraction procedure for determination of copper, lead and iron in natural water and food samples has been established in the presented work. 1-Phenylthiosemicarbazide (1-PTSC) as ligand and Dowex Optipore L-493 resin as adsorbent were used in a mini chromatographic column. Various analytical conditions for the quantitative recoveries of analyte ions including pH, amounts of adsorbent, eluent,

Ozden Y?ld?z; Demirhan Citak; Mustafa Tuzen; Mustafa Soylak

2011-01-01

406

Column Solid Phase Extraction of Copper, Iron, and Zinc Ions at Trace Levels in Environmental Samples on Amberlite XAD?7 for Their Flame Atomic Absorption Spectrometric Determinations  

Microsoft Academic Search

A column solid?phase extraction method for the separation and preconcentration of copper, zinc, and iron at trace levels has been established prior to their flame atomic absorption spectrometric determinations. Analytes from 0.5 M KSCN in a 1 M HCl solution were recovered using of an Amberlite XAD?7 column. The chemical variables affecting the analytical performance of the combined methodology including reagent amounts,

Mustafa Tuzen; Mustafa Soylak; Latif Elci; Mehmet Dogan

2004-01-01

407

Copper and iron-pillared clay catalysts for the WHPCO of model and real wastewater streams from olive oil milling production  

Microsoft Academic Search

The properties of copper-based pillared clays (Cu-PILC) have been studied and compared with those of the analogous iron-based clays (Fe-PILC) in the wet hydrogen peroxide catalytic oxidation (WHPCO) of model phenolic compounds (p-coumaric and p-hydroxybenzoic acids) and real olive oil milling wastewater (OMW). These two catalysts show comparable performances in all these reactions, although they show some differences in the

Simona Caudo; Gabriele Centi; Chiara Genovese; Siglinda Perathoner

2007-01-01

408

Coumarin-based fluorescent probes for dual recognition of copper(II) and iron(III) ions and their application in bio-imaging.  

PubMed

Two new coumarin-based "turn-off" fluorescent probes, (E)-3-((3,4-dihydroxybenzylidene)amino)-7-hydroxy-2H-chromen-2-one (BS1) and (E)-3-((2,4-dihydroxybenzylidene)amino)-7-hydroxy-2H-chromen-2-one (BS2), were synthesized and their detection of copper(II) and iron(III) ions was studied. Results show that both compounds are highly selective for Cu²? and Fe³? ions over other metal ions. However, BS2 is detected directly, while detection of BS1 involves a hydrolysis reaction to regenerate 3-amino-7-hydroxycoumarin (3) and 3,4-dihydroxybenzaldehyde, of which 3 is able to react with copper(II) or iron(III) ions. The interaction between the tested compounds and copper or iron ions is associated with a large fluorescence decrease, showing detection limits of ca. 10?? M. Preliminary studies employing epifluorescence microscopy demonstrate that Cu²? and Fe³? ions can be imaged in human neuroblastoma SH-SY5Y cells treated with the tested probes. PMID:24419164

García-Beltrán, Olimpo; Cassels, Bruce K; Pérez, Claudio; Mena, Natalia; Núñez, Marco T; Martínez, Natalia P; Pavez, Paulina; Aliaga, Margarita E

2014-01-01

409

Structural features and the reaction mechanism of cytochrome oxidase: iron and copper X-ray absorption fine structure.  

PubMed Central

X-ray edge absorption of copper and extended fine structure studies of both copper and iron centers have been made of cytochrome oxidase from beef heart, Paracoccus dentrificans, and HB-8 thermophilic bacteria (1-2.5 mM in heme). The desired redox state (fully oxidized, reduced CO, mixed valence formate and CO) in the x-ray beam was controlled by low temperature (-140 degrees C) and was continuously monitored by simultaneous optical spectroscopy and by electron paramagnetic resonance (EPR) monitoring every 30 min of x-ray exposure. The structure of the active site, a cytochrome a3-copper pair in fully oxidized and in mixed valence formate states where they are spin coupled, contains a sulphur bridge with three ligands 2.60 +/- 0.03 A from Fea3 and 2.18 +/- 0.03 A from Cua3. The distance between Fea3 and Cua3 is 3.75 +/- 0.05 A, making the sulphur bond angle 103 degrees reasonable for sp3 sulphur bonding. The Fea3 first shell has four typical heme nitrogens (2.01 +/