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1

Effects of dietary copper, cadmium, iron, molybdenum and manganese on selenium utilization by the rat  

SciTech Connect

The possible antagonistic effects of different dietary concentrations of copper (1.3-200 mg/kg), cadmium (1-5 mg/kg), iron (20-500 mg/kg), molybdenum (0.3-50 mg/kg) and manganese (0.2-200 mg/kg) on selenium utilization by the rat were studied by the measurement of the absorption and organ distribution of dietary selenium as (75Se)selenite and by effects on organ glutathione peroxidase (GSH-Px: EC 1.11.1.9) activity. Although a high concentration of copper (200 mg/kg) in the diet did not alter the percentage absorption and total-body retention of doses of 75SeO3(2)- by rats, after such treatment tissue 75Se distribution was changed and was lower total selenium in some tissues. After copper treatment (200 mg/kg diet) GSH-Px activity of liver, testis, kidney and whole blood was also lower. Dietary cadmium, iron, molybdenum and manganese at the concentrations investigated had no significant effects on selenium metabolism. Thus it is unlikely that copper, cadmium, iron, molybdenum and manganese at normal dietary concentrations will have a major effect on selenium metabolism in the rat, especially if adequate amounts of selenium are being consumed.

Abdel Rahim, A.G.; Arthur, J.R.; Mills, C.F.

1986-03-01

2

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

3

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

4

Determination of silver, bismuth, cadmium, copper, iron, nickel and zinc in lead- and tin-base solders and white-metal bearing alloys by atomic-absorption spectrophotometry.  

PubMed

A simple atomic-absorption spectrophotometry method is described for the determination of silver, bismuth, cadmium, copper, iron, nickel and zinc in lead- and tin-base solders and white-metal bearing alloys, with use of a single sample solution. The sample is dissolved in a mixture of hydrobromic acid and bromine, then fumed with sulphuric acid. The lead sulphate is dissolved in concentrated hydrochloric acid. The method is particularly suitable for the determination of silver and bismuth, which are co-precipitated with lead sulphate. The other elements can also be determined after removal of the lead sulphate by filtration. PMID:18964038

Chong, C

1986-01-01

5

Detection of copper, lead, cadmium and iron in wine using electronic tongue sensor system.  

PubMed

An array of 10 potentiometric chemical sensors has been applied to the detection of total Fe, Cu, Pb and Cd content in digested wine. As digestion of organic matter of wine is necessary prior to the trace metal detection using potentiometric sensors, sample preparation procedures have been optimized. Different variants of wet and microwave digestion and dry ashing, 14 conditions in total, have been tested. Decomposition of organic matter was assessed using Fourier transform mid-infrared spectroscopy and total phenolic content. Dry ashing was found to be the most effective method of wine digestion. Measurements with sensors in individual solutions of Fe(III), Cu(II), Pb(II) and Cd(II) prepared on different backgrounds have shown that their detection limits were below typical concentration levels of these metals in wines and, in the case of Cu, Pb and Cd below maximum allowed concentrations. Detection of Fe in digested wine samples was possible using discrete iron-sensitive sensors with chalcogenide glass membranes with RMSEP of 0.05 mmol L(-1) in the concentration range from 0.0786 to 0.472 mmol L(-1). Low concentration levels of Cu, Pb and Cd in wine and cross-sensitivity of respective sensors resulted in the non-linearity of their responses, requiring back-propagation neural network for the calibration. Calibration models have been calculated using measurements in the model mixed solutions containing all three metals and a set of digested wine sample. RMSEP values for Cu, Pb and Cd were 3.9, 39 and 1.2 ?mol L(-1) in model solutions and 2, 150 and 1 ?mol L(-1) in digested wine samples. PMID:25127565

Simões da Costa, A M; Delgadillo, I; Rudnitskaya, A

2014-11-01

6

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

7

Biotransference and biomagnification of selenium copper, cadmium, zinc, arsenic and  

E-print Network

Biotransference and biomagnification of selenium copper, cadmium, zinc, arsenic and lead the biotransference of selenium copper, cadmium, zinc, arsenic and lead was measured in a contaminated seagrass. Selenium was found to biomagnify, exceeding maximum permitted concentrations for human consumption within

Canberra, University of

8

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

9

Effect of iron upon cadmium-manganese and cadmium-iron interaction  

SciTech Connect

Increase cadmium production has enhanced the potential danger of this toxic metal including its effect upon the metabolism of some essential elements as, for instance, manganese of some essential elements as, for instance, manganese and iron. Relevant data about the cadmium-manganese interaction are rather scanty. Since there are more data of the effect of iron on the metabolism of either of these ions independently. The authors decided to investigate how the presence of iron affected the interaction between cadmium and manganese and how cadmium alone or in combination with the additional iron affected iron transfer and retention in the intestinal wall.

Gruden, N.; Munic, S.

1987-06-01

10

High copper concentrations in squid livers in association with elevated levels of silver, cadmium, and zinc  

Microsoft Academic Search

Livers from 43 Loligo opalescens, 14 Ommastrephes bartrami, and 7 Symplectoteuthis oualaniensis were analyzed for their silver, cadmium, copper, zinc and iron contents. Copper concentrations of up to 15,000 µg\\/g dry weight were found in L. opalescens in conjunction with significant correlations between this element and Ag, Cd and Zn. The latter elements are known to affect Cu metabolism in

J. H. Martin; A. R. Flegal

1975-01-01

11

STUDIES ON THE DETERMINATION OF TRACE OF ELEMENTS IN IRON AND STEELS. VII. SPECTROPHOTOMETRIC DETERMINATION OF MICRO AMOUNTS OF CADMIUM IN CAST IRON  

Microsoft Academic Search

An absorption photometric method for the determination of cadmium in ; cast iron by extraction as a dithizonate is described. The sample is decomposed ; by perchloric acid. After an addition of citric acid, ammonium hydroxide is ; added up to pH 9. Cadmium is extracted together with copper and nickel by ; dithizone --chloroform solution. From the extract, cadmium

S. Maekawa; Y. Yoneyama

1961-01-01

12

Acute lethality of copper, cadmium, and zinc to northern squawfish  

SciTech Connect

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 ..mu..g/liter for copper, 1104 ..mu..g/liter for cadmium, and 3693 ..mu..g/liter for zinc in 12/sup 0/C water. These values, when compared to those for chinook salmon and steelhead parr tested under similar conditions, show that the northern squawfish are more tolerant than the two salmonids to zinc and cadmium but equally sensitive to copper.

Andros, J.D.; Garton, R.R.

1980-03-01

13

Acute Lethality of Copper, Cadmium, and Zinc to Northern Squawfish  

Microsoft Academic Search

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 ?g\\/liter for copper, 1,104 ?g\\/liter for cadmium, and 3,693 ?g\\/liter for zinc in 12 C water. These values, when compared to those for chinook salmon and steelhead parr tested under similar conditions, show that the northern

James D. Andros; Ronald R. Garton

1980-01-01

14

Acute lethality of copper, cadmium, and zinc to northern squawfish  

Microsoft Academic Search

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 ..mu..g\\/liter for copper, 1104 ..mu..g\\/liter for cadmium, and 3693 ..mu..g\\/liter for zinc in 12°C water. These values, when compared to those for chinook salmon and steelhead parr tested under similar conditions, show that the northern squawfish

JAMES D. ANDROS; RONALD R. GARTON

1980-01-01

15

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

16

The distribution of zinc, cadmium, lead and copper within the hepatopancreas of a woodlouse.  

PubMed

The distribution of metals within the hepatopancreas of Oniscus asellus (Crustacea, Isopoda) from two uncontaminated sites, and two sites contaminated with zinc, cadmium and lead, has been studied by atomic absorption spectrophotometry, light microscopy, transmission and scanning electron microscopy and X-ray microanalysis. The hepatopancreas contains two types of intracellular granule. The first type, in the S cells, are spherical granules which contain copper, sulphur and calcium. In woodlice from contaminated sites, these 'copper' granules, also contain zinc, cadmium and lead. The second type, in the B cells, are flocculent deposits which contain iron. In woodlice from contaminated sites, these 'iron' granules also contain zinc and lead. Moribund woodlice from contaminated sites have large numbers of 'copper' and 'iron' granules in the hepatopancreas and a fine deposit of zinc and lead on the membranes of the cells. There are numerous microorganisms in close association with the microvillous border of the hepatopancreas of woodlice from all four sites. Within the microorganisms of Oniscus asellus from contaminated sites, there are deposits of material which contain zinc, lead, calcium and phosphorus 'Copper' and 'iron' granules could have evolved as storage sites for essential metals to be utilized when demand from the body exceeds uptake from the food. Woodlice in contaminated sites may be able to 'detoxify' potentially harmful amounts of essential and non-essential metals by storing them in a relatively insoluble form within these granules. PMID:7170709

Hopkin, S P; Martin, M H

1982-01-01

17

Water Research 37 (2003) 21732185 Natural variation of copper, zinc, cadmium and selenium  

E-print Network

Water Research 37 (2003) 2173­2185 Natural variation of copper, zinc, cadmium and selenium 2002; accepted 22 November 2002 Abstract Copper, zinc, cadmium and selenium were measured the accumulation of trace metals in contaminated environments. Copper, zinc, cadmium and selenium concentrations

Canberra, University of

18

Cadmium, copper and zinc in octopuses from Kerguelen Islands, Southern Indian Ocean  

E-print Network

Cadmium, copper and zinc in octopuses from Kerguelen Islands, Southern Indian Ocean P. Bustamante1-en-Bois, France ABSTRACT: Concentrations of cadmium, copper and zinc were measured in 34 octopuses over a large: Cephalopods . Octopus . Sub-Antarctic . Heavy metals . Cadmium . Digestive gland . Detoxification processes

Paris-Sud XI, Université de

19

Follow up of Treatment of Cadmium and Copper Toxicity in Clarias Gariepinus Using Laser Techniques  

NASA Astrophysics Data System (ADS)

Two purified diets were formulated and fed to seven groups of the Nile catfish; Clarias gariepinus for 12 weeks. The formulated diets contained 50 or 500 mg/kg diet of an ascorbic acid equivalent, supplied by L-ascorbyl-2-monophosphate (Mg salt). Laser induced breakdown spectroscopy (LIDS) technique has been used to characterize the bioaccumulation of cadmium, copper and iron in some selected organs (Gills, liver, kidney and muscles) and disturbance in the distribution of sodium, calcium and magnesium in gills and muscles of fish fed the minimum requirement of vitamin C (50 mg/kg diet) and exposed to cadmium (0.165 mg/l) and copper (0.35 mg/l) individually or in combination. Heavy metals bioaccumulation affect histological structure of gills, liver and kidney and consequently, fish exhibited the lowest growth rate and meat quality with a progressive fall in RBCs count, Hb content and haematocrite value. These effects were concomitant with significant increase in the WBCs count, serum glucose, total protein, AST, ALT, creatinine and uric acid. On the contrary, serum total lipids and liver glycogen revealed a significant decrease. However, fish fed 500 mg vitamin C/kg diet and exposed to the same concentrations of cadmium and copper either individually or in mixture showed an improvement in the growth rate and meat quality and a tendency to exhibit close to the control values for most of the other studied physiological, biochemical and histopathological investigations.

Zaghloul, Khalid H.; Ali, Maha F.; El-Bary, Manal G. Abd; Abd El-Harith, Mohamed

2010-04-01

20

Effects of Cadmium and Copper Biosorption on Chlorella vulgaris.  

PubMed

Changes in protein levels and lipid compositions in algal cells indicate the severity of stress related to toxic concentrations of heavy metals. In this study, the effects of exposure to cadmium and copper on Chlorella vulgaris and its capacity to remove metals were evaluated. The data revealed ion removal activity by microalgae under all treatments and different levels of protein expression after 48 h of exposure. Furthermore, we analyzed lipids contents to characterize them. PMID:25151280

de Abreu, Fabiano C P; da Costa, Péricles N M; Brondi, Ariadne M; Pilau, Eduardo J; Gozzo, Fábio C; Eberlin, Marcos N; Trevisan, Marcello G; Garcia, Jerusa S

2014-10-01

21

Copper deficiency increases iron absorption in the rat.  

PubMed

Release of iron from enterocytes and hepatocytes is thought to require the copper-dependent ferroxidase activity of hephaestin (Hp) and ceruloplasmin (Cp), respectively. In swine, copper deficiency (CD) impairs iron absorption, but whether this occurs in rats is unclear. By feeding a diet deficient in copper, CD was produced, as evidenced by the loss of copper-dependent plasma ferroxidase I activity, and in enterocytes, CD reduced copper levels and copper-dependent oxidase activity. Hematocrit was reduced, and liver iron was doubled. CD reduced duodenal mucosal iron and ferritin, whereas CD increased iron absorption. Duodenal mucosal DMT1-IRE and ferroportin1 expression remained constant with CD. When absorption in CD rats was compared with that seen normally and in iron-deficient anemic animals, strong correlations were found among mucosal iron, ferritin, and iron absorption, suggesting that the level of iron absorption was appropriate given that the erythroid and stores stimulators of iron absorption are opposed in CD. Because CD reduced the activity of Cp, as evidenced by copper-dependent plasma ferroxidase I activity and hepatocyte iron accumulation, but iron absorption increased, it is unlikely that the ferroxidase activity of Hp is important and suggests another function for this protein in the export of iron from the enterocyte during iron absorption. Also, the copper-dependent ferroxidase activity of Cp does not appear important for iron efflux from macrophages, because Kupffer cells of the liver and nonheme iron levels of the spleen were normal during copper deficiency, suggesting another role for Cp in these cells. PMID:12760904

Thomas, Carla; Oates, Phillip S

2003-11-01

22

Cadmium effects in rats on tissue iron, selenium, and blood pressure; blood and hair cadmium in some oregon residents.  

PubMed

Exposure of rats to cadmium causes a marked depletion of iron in liver and kidney. Selenium neither counteracts or intensifies the influence of cadmium on tissue iron levels. Selenium injections protect against cadmium-induced testicular damage but cause this element to accumulate in the testes at higher concentration than in animals exposed to cadmium without selenium. Selenium injection diverts the binding of cadmium from low molecular weight proteins to high molecular weight ones. Dosing rats with selenium and cadmium or inclusion of Se or Cd in the diet did not result in altered cadmium binding in tissues, raising some questions concerning the environmental significance of these injection experiments. Addition of selenium to a diet containing cadmium decreased the accumulation of cadmium in liver and kidney, but increased its deposition in testes. The metabolism of cadmium bound to metallothionein was markedly different as compared to the inorganic salt of this element. Dietary ascorbate, but not citrate or cysteine, decreased the deposition of cadmium in rat tissues. In some low-level exposure experiments with cadmium (1 to 1000 ppb), no differences were found in the percentage of dose absorbed or rate of cadmium accumulation when provided in food versus water. Female rats tended to absorb more cadmium than males. The binding of cadmium to cytosolic proteins was found to be different between rats fed low levels of cadmium (up to 1 ppm) as compared to those fed high levels of this element (100 ppm). Cadmium was not found to contribute to hypertension in rats, and a summary of results by various investigators is presented. Blood and hair cadmium levels in Oregon residents were found to be highest in employees of a mine, and hair cadmium was found to be respectively higher in smokers than nonsmokers and in metal workers than office workers. No relationships were observed in humans between blood or hair cadmium levels and blood pressure. PMID:488028

Whanger, P D

1979-02-01

23

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

24

Growth of Trichosporon cutaneum R 57 in the Presence of Toxic Concentration of Cadmium and Copper  

Microsoft Academic Search

The filamentous yeast Trichosporon cutaneum R57 strain was cultivated in batch mode on a liquid medium in the presence of increased concentrations of cadmium and copper ions (from 1 to 112 mg L -1 ). The experiments elucidated the ability of the investigated strain to grow and to accumulate cadmium and copper ions. The obtained results have shown low to

NELLY GEORGIEVA

25

Physiological responses of Lemna trisulca L. (duckweed) to cadmium and copper bioaccumulation  

Microsoft Academic Search

Aquatic plants are known to accumulate and bioconcentrate heavy metals. In this study, several physiological responses of aquatic vascular plant Lemna trisulca L. to elevated concentrations of cadmium (up to 10 mM) and copper (up to 50 ?M) were investigated. It was found that Lemna fronds were able to accumulate both cadmium and copper, but Cu-treated material showed pronounced toxic

M. N. V Prasad; P Malec; A Waloszek; M Bojko; K Strza?ka

2001-01-01

26

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

27

Sorption of cadmium and copper ions on natural and synthetic hydroxylapatite particles  

Microsoft Academic Search

The sorption of divalent cadmium and copper ions from aqueous solutions on natural and synthetic hydroxyapatite was investigated by the batch method and under dynamic conditions in columns at 22 °C and pH 5. The effect of cadmium and copper concentration on sorption was studied. Both types of apatites are efficient, despite their different composition and morphology. The sorption mechanism involves

F. Fernane; M. O. Mecherri; P. Sharrock; M. Hadioui; H. Lounici; M. Fedoroff

2008-01-01

28

Effect of Acute and Subchronic Exposure to Cadmium on the Retention of Iron in Rats  

Microsoft Academic Search

The influence of cadmium on the retention of a single dose of iron after acute and subchronic treatment with cadmium was studied in normal rats. Additionally the results were compared with iron retention in unexposed iron-defi cient animals. Test solutions contained iron and cadmium in various molar ratios (Fe:Cd = 1:0, 1:0.5, 1:1, 1:2 jimol\\/kg body weight). In acute experiments

SIEGFRIED G. SCHÃ; FER ANDWOLFGANG FORTH

29

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

30

Iron versus Copper II. Principles and Applications in Bioinorganic Chemistry.  

ERIC Educational Resources Information Center

Discusses the differences between iron and copper. Describes various aspects of the behaviors of these two elements, including those of biological and environmental significance. Addresses the evolution of the atmosphere and sedimentary ore formation, the phylogeny of iron and copper, and some anthropological notes regarding the use of the metals.…

Ochiai, Ei-Ichiro

1986-01-01

31

Old Iron, Young Copper: from Mars to Venus  

Microsoft Academic Search

Iron and copper are metals which play an important role in the living world. From a brief consideration of their chemistry and biochemistry we conclude that the early chemistry of life used water soluble ferrous iron while copper was in the water-insoluble Cu(I) state as highly insoluble sulphides. The advent of oxygen was a catastrophic event for most living organisms,

R. R. Crichton; J.-L. Pierre

2001-01-01

32

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

33

Determination of Cadmium and Copper in Fish Samples from Sir And Menzelet Dam Lake Kahramanmara?, Turkey  

Microsoft Academic Search

The cadmium and copper levels were determined in the total of 126 fish samples which belongs to five fish species collected\\u000a from S?r and Menzelet Dam Lakes in Kahramanmara? Province by Atomic Absorption Spectrophotometer. The concentrations of heavy\\u000a metals were expressed as ppm wet weight of tissue. The mean levels of cadmium and copper in muscle, liver and gill tissues

Özlem Erdo?rul; D. Ayfer Ate?

2006-01-01

34

TOXICITIES OF CADMIUM, COPPER, AND ZINC TO FOUR JUVENILE STAGES OF CHINOOK SALMON AND STEELHEAD  

EPA Science Inventory

Continuous-flow toxicity tests were conducted to determine the relative tolerances of newly hatched alevins, swim-up alevins, parr, and smolts of chinook salmon (Oncorhyncus tshawytscha) to cadmium, copper, and zinc. Newly hatched alevins were much more tolerant to cadmium and, t...

35

A comparative study of cadmium and copper in ruffed grouse ( Bonasa umbellus) in regions with and without historic mining  

Microsoft Academic Search

Mining activities can increase the bioavailability of metals in aquatic and terrestrial ecosystems. Following over 100 years of copper mining in portions of Michigan's Upper Peninsula (UP) terrestrial ecosystems retain vast quantities of waste rock with traces of cadmium and large concentrations of copper. We compared liver cadmium and copper concentrations in ruffed grouse (Bonasa umbellus), a popular game bird

Marian Snively; David J. Flaspohler

2006-01-01

36

Removal of copper and cadmium from aqueous solution using switchgrass biochar produced via hydrothermal carbonization process.  

PubMed

Biochar produced from switchgrass via hydrothermal carbonization (HTC) was used as a sorbent for the removal of copper and cadmium from aqueous solution. The cold activation process using KOH at room temperature was developed to enhance the porous structure and sorption properties of the HTC biochar. The sorption efficiency of HTC biochar and alkali activated HTC biochar (HTCB) for removing copper and cadmium from aqueous solution were compared with commercially available powdered activated carbon (PAC). The present batch adsorption study describes the effects of solution pH, biochar dose, and contact time on copper and cadmium removal efficiency from single metal ion aqueous solutions. The activated HTCB exhibited a higher adsorption potential for copper and cadmium than HTC biochar and PAC. Experiments conducted with an initial metal concentration of 40 mg/L at pH 5.0 and contact time of 24 h resulted in close to 100% copper and cadmium removal by activated HTCB at 2 g/L, far greater than what was observed for HTC biochar (16% and 5.6%) and PAC (4% and 7.7%). The adsorption capacities of activated HTCB for cadmium removal were 34 mg/g (0.313 mmol/g) and copper removal was 31 mg/g (0.503 mmol/g). PMID:22687632

Regmi, Pusker; Garcia Moscoso, Jose Luis; Kumar, Sandeep; Cao, Xiaoyan; Mao, Jingdong; Schafran, Gary

2012-10-30

37

Cadmium and copper toxicity in three marine macroalgae: evaluation of the biochemical responses and DNA damage.  

PubMed

Marine macroalgae have evolved a different mechanism to maintain physiological concentrations of essential metal ions and non-essential metals. The objective of the present work was to evaluate the antioxidant response and DNA damage of copper and cadmium ions in three halophytes, namely, Acanthophora spicifera, Chaetomorpha antennina, and Ulva reticulata. Accumulation of copper was significantly higher (P?cadmium. Biochemical responses showed that copper was considerably more toxic than cadmium (P?copper and cadmium in seaweeds. The present study also showed that copper and cadmium increased oxidative stress and induced antioxidant defense systems against reactive oxygen species. The order of toxicity for metals in the studied seaweeds was U. reticulata > A. spicifera > C. antennina. DNA damage index analysis supported that copper was significantly (P?cadmium. Bioaccumulation, biochemical responses, and DNA damage observed in the here analyzed marine macroalgae after exposure to selected metals indicate that these marine organisms represent useful bioindicators of marine pollution. PMID:24859697

Babu, M Yokesh; Palanikumar, L; Nagarani, N; Devi, V Janaki; Kumar, S Ramesh; Ramakritinan, C M; Kumaraguru, A K

2014-08-01

38

Zinc and cadmium specifically interfere with RNA-binding activity of human iron regulatory protein 1  

Microsoft Academic Search

The cellular pro-oxidative stress induced by high zinc concentrations or cadmium is most likely mediated by disruption of redox (mainly thiol) homeostasis or by mishandling of redox-active transition metals. The impact of zinc and cadmium on the main regulators of iron homeostasis in metazoans, the iron regulatory proteins (IRP) 1 and 2, has been probed with the human recombinant proteins.

Alain Martelli; Jean-Marc Moulis

2004-01-01

39

Biochemical and Physiological Responses in Atlantic Salmon ( Salmo salar) Following Dietary Exposure to Copper and Cadmium  

Microsoft Academic Search

Three experiments were conducted with Atlantic salmon (Salmo salar) to assess the effects of dietary exposure to copper and cadmium. The results presented here provide an overview, details of each experiment will be published in full elsewhere. In the first experiment, salmon parr exposed for four weeks to 35 and 700 mg Cu kg?1 diet had significantly elevated intestinal copper

A.-K Lundebye; M. H. G Berntssen; S. E. Wendelaar Bonga; A Maage

1999-01-01

40

Ecological risk assessment of copper and cadmium in surface waters of Chesapeake Bay watershed  

SciTech Connect

This ecological risk assessment was designed to characterize risk of copper and cadmium exposure in the Chesapeake Bay watershed by comparing the probability distributions of environmental exposure concentrations with the probability distributions of species response data determined from laboratory studies. The overlap of these distributions was a measure of risk to aquatic life. Dissolved copper and cadmium exposure data were available from six primary data sources covering 102 stations in 18 basins in the Chesapeake Bay watershed from 1985 through 1996. Highest environmental concentrations of copper (based on 90th percentiles) were reported in the Chesapeake and Delaware (C and D) Canal, Choptank River, Middle River, and Potomac River; the lowest concentrations of copper were reported in the lower and middle mainstem Chesapeake Bay and Nanticoke River. Based on the calculation of 90th percentiles, cadmium concentrations were highest in the C and D Canal, Potomac River, Upper Chesapeake Bay, and West Chesapeake watershed. Lowest environmental concentrations of cadmium were reported in the lower and middle mainstem Chesapeake Bay and Susquehanna River. The ecological effects data used for this risk assessment were derived primarily from acute copper and cadmium laboratory toxicity tests conducted in both fresh water and salt water; chronic data were much more limited. The 10th percentile (concentration protecting 90% of the species) for all species derived from the freshwater acute copper toxicity database was 8.3 {micro}g/L. For acute saltwater copper data, the 10th percentile for all species was 6.3 {micro}g/L copper. The acute 10th percentile for all saltwater species was 31.7 {micro}g/L cadmium. Highest potential ecological risk from copper exposures was reported in the C and D Canal area of the northern Chesapeake Bay watershed.

Hall, L.W. Jr.; Scott, M.C.; Killen, W.D. [Univ. of Maryland Agricultural Experiment Station, Queenstown, MD (United States). Wye Research and Education Center

1998-06-01

41

Effect of zinc on copper and iron bioavailability as influenced by dietary copper and fat source  

SciTech Connect

In a number of experiments, they have observed that liver copper levels of young male rats fed low zinc diets were essentially the same as liver copper levels of rats fed adequate zinc. Liver iron levels of rats fed low zinc diets, however, tended to be markedly higher than liver iron levels of rats fed adequate zinc. Increases in dietary zinc (up to 200 ppm) were generally associated with decreases in liver iron deposition, but had little effect on liver copper deposition. Iron bioavailability appeared to be enhanced when fat sources high in saturated fatty acids were used, and there was evidence that the type of dietary fat influenced the effect of zinc on iron bioavailability. Liver copper deposition, however, did not appear to be markedly affected by the type of dietary fat suggesting that copper bioavailability is less affected by fat source. Increases in dietary copper were associated with increases in liver copper levels and decreases in liver iron levels of rats fed increasing levels of zinc. These data suggest that potential interrelationships between dietary factors not being considered as experimental variables could have significant effects on results and on the interrelationships between dietary variables which are being studied.

Magee, A.C.; Jones, B.P.; Lin, F.; Sinthusek, G.; Frimpong, N.A.; Wu, S.

1986-03-05

42

Reductive iron uptake by Candida albicans: role of copper, iron and the TUP1 regulator  

Microsoft Academic Search

High-affinity iron uptake by a ferrous permease in the opportunistic pathogen Candida albicans is required for virulence. Here this iron uptake system has been characterized by investigating three distinct activities: an externally directed surface ferric reductase, a membrane-associated PPD ( p- phenylenediamine) oxidase and a cellular ferrous iron transport activity. Copper was required for the PPD oxidase and ferrous transport

Simon A. B. Knight; Emmanuel Lesuisse; Robert Stearman; Richard D. Klausner; Andrew Dancis

43

Iron, copper, and iron regulatory protein 2 in Alzheimer's disease and related dementias  

Microsoft Academic Search

Accumulating evidence implicates a role for altered iron and copper metabolism in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease (AD). However, imbalances in the levels of the various forms of iron at different stages of AD have not been examined. In this pilot study we extracted and measured the levels of loosely bound, non-heme and total iron and

Shino Magaki; Ravi Raghavan; Claudius Mueller; Kerby C. Oberg; Harry V. Vinters; Wolff M. Kirsch

2007-01-01

44

Influence of iron and zinc status on cadmium accumulation in Bangladeshi women  

SciTech Connect

Cadmium is a widespread environmental contaminant present in food. The absorption in the intestine increases in individuals with low iron stores, but the effect of zinc deficiency is not clear. The aim of the present study was to assess the influence of iron and zinc status on cadmium accumulation in pregnant Bangladeshi women. We measured cadmium in urine from 890 women using inductively coupled plasma mass spectrometry (ICPMS). Further, we also measured ferritin and zinc in plasma. The median cadmium concentration in urine was 0.59 {mu}g/L (adjusted to mean specific gravity of 1.012 g/mL). Analysis of covariance (ANCOVA) showed that urinary cadmium was associated with plasma ferritin and plasma zinc via a significant interaction between dichotomized plasma ferritin and plasma zinc. The analysis was adjusted for age and socioeconomic status. Women with low iron stores and adequate zinc status had significantly higher urinary cadmium compared to women with both adequate iron stores and zinc status. There was no difference in urinary cadmium between women with both low iron stores and zinc status compared to those with both adequate iron stores and zinc status. In conclusion, low iron stores were associated with increased cadmium accumulation, but only at adequate zinc status.

Kippler, Maria [Institute of Environmental Medicine, Karolinska Institutet, Stockholm (Sweden); Ekstroem, Eva-Charlotte [International Maternal and Child Health, Uppsala University, Uppsala (Sweden); Loennerdal, Bo [Department of Nutrition, University of California, Davis, CA 95616 (United States); Goessler, Walter [Institut fuer Chemie - Analytische Chemie, Karl-Franzens-Universitaet, Graz (Austria); Akesson, Agneta [Institute of Environmental Medicine, Karolinska Institutet, Stockholm (Sweden); El Arifeen, Shams [International Centre for Diarrhoeal Disease Research, Bangladesh - ICDDR-B, GPO Box 128, Dhaka 1000 (Bangladesh); Persson, Lars-Ake [International Maternal and Child Health, Uppsala University, Uppsala (Sweden); Vahter, Marie [Institute of Environmental Medicine, Karolinska Institutet, Stockholm (Sweden)]. E-mail: Marie.Vahter@ki.se

2007-07-15

45

Iron-Deficiency Induces Cadmium Uptake and Accumulation in Solanum nigrum L  

Microsoft Academic Search

Phytoremediation is a promising tool in removing pollutants from the environment or in rendering them harmless. The objective\\u000a of this research was to determine the effect of iron-deficiency on the uptake of cadmium by Solanum nigrum L. Results showed that iron-deficiency induced cadmium uptake, biomass decrease and changes in pH and Eh in hydroponic culture.\\u000a Under iron-deficiency status, the decrease

Tong Bao; Lina Sun; Tieheng Sun; Pin Zhang; Zhixin Niu

2009-01-01

46

Phytoremediation of soil contaminated with cadmium, copper and polychlorinated biphenyls.  

PubMed

A pot experiment and afield trial were conducted to study the remediation of an aged field soil contaminated with cadmium, copper and polychlorinated biphenyls (PCBs) (7.67 +/- 0.51 mg kg(-1) Cd, 369 +/- 1 mg kg(-1) Cu in pot experiment; 8.46 +/- 0.31 mg kg(-1) Cd, 468 +/- 7 mg kg(-1) Cu, 323 +/- 12 microg kg(-1) PCBs for field experiment) under different cropping patterns. In the pot experiment Sedum plumbizincicola showed pronounced Cd phytoextraction. After two periods (14 months) of cropping the Cd removal rates in these two treatments were 52.2 +/- 12.0 and 56.1 +/- 9.1%, respectively. Total soil PCBs in unplanted control pots decreased from 323 +/- 11 to 49.3 +/- 6.6 microg kg(-1), but with no significant difference between treatments. The field microcosm experiment intercropping of three plant species reduced the yield of S. plumbizincicola, with a consequent decrease in soil Cd removal. S. plumbizincicola intercropped with E. splendens had the highest shoot Cd uptake (18.5 +/- 1.8 mg pot(-1)) after 6 months planting followed by intercropping with M. sativa (15.9 +/- 1.9 mg pot(-1)). Liming with S. plumbizincicola intercropped with M. sativa significantly promoted soil PCB degradation by 25.2%. Thus, adjustment of soil pH to 5.56 combined with intercropping with S. plumbizincicola and M. sativagave high removal rates of Cd, Cu, and PCBs. PMID:22908627

Wu, Longhua; Li, Zhu; Han, Cunliang; Liu, Ling; Teng, Ying; Sun, Xianghui; Pan, Cheng; Huang, Yujuan; Luo, Yongming; Christie, Peter

2012-07-01

47

Effect of excess iron and copper on physiology of aquatic plant Spirodela polyrrhiza (L.) Schleid.  

PubMed

To elucidate effect of chemical reagents addition on growth of aquatic plants in restoration of aquatic ecosystem, Spirodela polyrrhiza (L.) Schleid was used to evaluate its physiological responses to excess iron (Fe(3+)) and copper (Cu(2+)) in the study. Results showed that accumulation of iron and copper both reached maximum at 100 mg L(-1) iron or copper after 24 h short-term stress, but excess iron and copper caused plants necrosis or death and colonies disintegration as well as roots abscission at excess metal concentrations except for 1 mg L(-1) iron. Significant differences in chlorophyll fluorescence (Fv/Fm) were observed at 1-100 mg L(-1) iron or copper. The synthesis of chlorophyll and protein as well as carbohydrate and the uptake of phosphate and nitrogen were inhibited seriously by excess iron and copper. Proline content decreased with increasing iron or copper concentration, however, MDA content increased with increasing iron or copper concentration. PMID:19260045

Xing, Wei; Huang, Wenmin; Liu, Guihua

2010-04-01

48

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

49

The copper-iron connection: hereditary aceruloplasminemia.  

PubMed

Hereditary aceruloplasminemia is an autosomal recessive disorder of iron homeostasis due to loss-of-function mutations in the ceruloplasmin gene. Affected individuals may present in adulthood with evidence of hepatic iron overload, diabetes, peripheral retinal degeneration, dystonia, dementia, or dysarthria. Laboratory studies demonstrate microcytic anemia, elevated serum ferritin, and a complete absence of serum ceruloplasmin ferroxidase activity. Consistent with the observed neurologic findings, magnetic resonance imaging reveals iron accumulation within the basal ganglia. Histologic studies detect abundant iron in hepatocytes, reticuloendothelial cells of the liver and spleen, beta cells of the pancreas, and astrocytes and neurons throughout the central nervous system. Characterization of this disorder reveals an essential role for ceruloplasmin in determining the rate of iron efflux from cells with mobilizable iron stores and provides new insights into the mechanisms of human iron metabolism. PMID:12382203

Nittis, Thalia; Gitlin, Jonathan D

2002-10-01

50

Toxicities of Cadmium, Copper, and Zinc to Four Juvenile Stages of Chinook Salmon and Steelhead  

Microsoft Academic Search

Continuous-flow toxicity tests were conducted to determine the relative tolerances of newly hatched alevins, swim-up alevins, parr, and smolts of chinook salmon (Oncorhynchus tshawytscha) and steelhead (Salmo gairdneri) to cadmium, copper, and zinc. Newly hatched alevins were much more tolerant to cadmium and, to a lesser extent, to zinc than were later juvenile forms. However, the later progression from swim-up

GARY A. CHAPMAN

1978-01-01

51

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

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

Canadian soil quality criteria for lead, copper, arsenic, cadmium and mercury  

SciTech Connect

National soil quality criteria for the protection of ecological receptors, including livestock and wildlife, are currently under development in Canada. Based on an evaluation of direct soil contact and soil and food ingestion pathways for sensitive species, soil quality criteria for lead, copper, arsenic, cadmium and mercury for three land use categories have been derived. The draft values, in mg/kg soil, for agricultural, residential/parkland, commercial/industrial land uses are: mercury, 4, 4, 30; copper, 62, 62, 100; cadmium, 10, 10, 27; lead, 70, 250, 400; arsenic, 17, 17, 26. Critical data requirements in developing soil quality criteria are also reviewed.

Gaudet, C.; Milne, D.; Teed, S.; Lin, J.; Raju, G.S.; Ouellet, S. [Environment Canada, Hull, Quebec (Canada)

1995-12-31

54

Accumulation and egestion of dietary copper and cadmium by the grasshopper Locusta migratoria R & F (Orthoptera: Acrididae)  

Microsoft Academic Search

Copper and cadmium budgets were studied for a model insect herbivore\\/host plant system comprising the oligophagous leaf-chewing grasshopper (Locusta migratoria) feeding on Zea mays (Gramineae). Fifth instar larvae were fed, for between 5 and 20 days, on maize foliage contaminated with either copper, cadmium or on control foliage containing no excess metal. Male and female locusts fed on copper-treated maize

Linda A. Crawford; Nicholas W. Lepp; Ian D. Hodkinson

1996-01-01

55

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

56

Accumulation and egestion of dietary copper and cadmium by the grasshopper Locusta migratoria R & F (Orthoptera: Acrididae).  

PubMed

Copper and cadmium budgets were studied for a model insect herbivore/host plant system comprising the oligophagous leaf-chewing grasshopper (Locusta migratoria) feeding on Zea mays (Gramineae). Fifth instar larvae were fed, for between 5 and 20 days, on maize foliage contaminated with either copper, cadmium or on control foliage containing no excess metal. Male and female locusts fed on copper-treated maize retained 45 and 42% of ingested copper respectively, figures not significantly different from the 41 and 33% retained on untreated maize. Remaining copper was egested with the faeces. Locusts fed on copper-treated maize showed an increase of 27% in body copper burden compared with those on the control diet: the increase was independent of time on the diet. Female locusts retained 33% and males 21% of ingested cadmium. Faecal cadmium levels were elevated, and accumulation in both sexes was proportional to time on the Cd-enriched diet. For both copper and cadmium, some ingested metal probably passed directly through the locust gut, bound to undigested food material. Results suggest that grasshoppers may effectively regulate excess dietary copper, but are unable efficiently to regulate cadmium. PMID:15091374

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

1996-01-01

57

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

58

Iron supplementation in pregnancy and breastfeeding and iron, copper and zinc status of lactating women from a human milk bank.  

PubMed

This study evaluated the influence of iron supplementation in pregnancy and breastfeeding on iron status of lactating women from a Brazilian Human Milk Bank. Blood and mature breast milk samples were collected from 145 women for assessment of iron status, as well as copper and zinc status. Haemoglobin, serum iron and ferritin were determined, respectively, by electronic counting, colorimetry and chemiluminescence. Transferrin and ceruloplasmin were analysed by nephelometry. Serum copper and zinc were measured by atomic absorption spectrophotometry, and serum alkaline phosphatase was measured by a colorimetric method. Iron, zinc and copper in breast milk were determined by spectrometry. Mean values of iron, copper and zinc (blood and breast milk) were compared by ANOVA, followed by Tukey's test. Iron supplementation was beneficial to prevent anaemia in pregnancy but not effective to treat anaemia. During breastfeeding, iron supplementation had a negative effect on maternal copper status, confirming an interaction between these micronutrients. PMID:23070740

Mello-Neto, Julio; Rondó, Patricia Helen Carvalho; Oshiiwa, Marie; Morgano, Marcelo Antonio; Zacari, Cristiane Zago; dos Santos, Mariana Lima

2013-04-01

59

Lead, zinc, cadmium, mercury, selenium and copper in Greenland caribou and reindeer ( Rangifer tarandus)  

Microsoft Academic Search

Samples of caribou and reindeer muscle (127 samples) and liver (126 samples) were collected from four locations during two seasons plus 3 years in Greenland. The levels of lead, zinc, cadmium, mercury, selenium, and copper were determined, and analyzed in relation to location, two seasons, age and year of sampling. The lead concentrations (geometric mean) ranged from below the detection

P Aastrup; F Riget; R Dietz; G Asmund

2000-01-01

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

Copper, cadmium, and nickel accumulation in crayfish populations near copper-nickel smelters at Sudbury, Ontario, Canada  

SciTech Connect

The Sudbury basin, an elliptical 646 square mile depression containing a number of freshwater reservoirs, has been subjected to extreme ecological disturbances from logging, mining and smelting activities. The purpose of the present study was to compare tissue concentration of copper, cadmium and nickel in freshwater crayfish at selected distances of the habitat from the emission source. Various tissue concentrations in crayfish from the sites were also examined to determine if particular body tissues were specific sites for metal accumulation.

Bagatto, G.; Aikhan, M.A.

1987-03-01

62

A comparative study of cadmium and copper in ruffed grouse (Bonasa umbellus) in regions with and without historic mining.  

PubMed

Mining activities can increase the bioavailability of metals in aquatic and terrestrial ecosystems. Following over 100 years of copper mining in portions of Michigan's Upper Peninsula (UP) terrestrial ecosystems retain vast quantities of waste rock with traces of cadmium and large concentrations of copper. We compared liver cadmium and copper concentrations in ruffed grouse (Bonasa umbellus), a popular game bird from landscapes with and without historic mining. We also used chickens (Gallus domesticus) to determine whether mine waste was a direct source of liver cadmium. Cadmium and copper levels did not differ between mining areas in Michigan and non-mining areas in Wisconsin. We found nearly significant difference between sexes in cadmium levels. Cadmium levels for all chickens were below the method detection limit of the lab (0.03 mg/kg) and copper levels did not differ in the experimental chickens. These results suggest that the historic mining in the western UP is not leading to higher cadmium or copper uptake in grouse. PMID:16750853

Snively, Marian; Flaspohler, David J

2006-10-01

63

Cadmium exposure affects iron acquisition in barley (Hordeum vulgare) seedlings.  

PubMed

This study addresses the question of the interference between iron (Fe) nutrition and cadmium (Cd) toxicity at the level of growth performance, phytosiderophores (PS) release, micronutrient accumulation and expression of genes involved in Fe homeostasis in barley seedlings, a plant with strategy II-based response to Fe shortage. Cd exposure induced responses similar to those of genuine Fe deficiency also in Fe-sufficient plants. Most genes involved in PS biosynthesis and secretion (HvNAS3, HvNAS4, HvNAS6, HvNAS7, HvNAAT-A, HvDMAS1 and HvTOM1) induced by Fe deprivation were also significantly upregulated in the presence of Cd under Fe sufficient conditions. Accordingly, the enhanced expression of these genes in roots under Cd exposure was accompanied by an increase of PS release. However, induced expression of HvIRO2 and the downregulation of HvIDEF1 and HvIRT1, after Cd exposure, suggested the presence of a pathway that induces HvIRO2-mediated PS biosynthesis under Cd stress, which probably is not simply caused by Fe deficiency. The downregulation of HvIRT1 and HvNramp5 may represent a protective mechanism at transcriptional level against further Cd uptake by these transporters. These results likely indicate that Cd itself may be able to activate Fe acquisition mechanism in an Fe-independent manner. PMID:24724721

Astolfi, Stefania; Ortolani, Maria R; Catarcione, Giulio; Paolacci, Anna R; Cesco, Stefano; Pinton, Roberto; Ciaffi, Mario

2014-12-01

64

The effects of copper and iron deficiencies in the chick  

E-print Network

rusty swords in drinking water to cure anemia. Both Syndenham in 1664 and Willis in 1681 showed that giving cholybeate water or salts of iron to chlorotic indivi- duals would restore the pink color to their cheeks (Fowler, 1936) . The presence... In 1928, Hart et al. demonstrated the importance of copper and iron in correcting the anemia of rats fed diets consisting only of milk. It was found that young weanling rats placed on a diet of whole cow's milk developed anemia in six to eight weeks...

McGhee, Flin Cameron

2012-06-07

65

Dietary Cadmium, Zinc and Copper: Effects on Chick Lung Morphology and Elastin Cross-linking1  

Microsoft Academic Search

ABSTRACT Day-old White Leghorn cockerels were divided into seven dietary groups and,fed one of the following diets: 7) a casein-based basal diet; 2) a casein-based diet supplemented with 10 mg\\/kg cadmium, 3) 100 mg\\/kg cadmium, 4) or 800 mg\\/kg zinc; 5) a casein-based diet pair-fed to the 100 mg\\/kg,Cd group; 6) a spray-dried nonfat milk-based diet with no added copper,

MICHAEL LEFEVRE; HELEN HENG ANDR; B. RUCKER

2009-01-01

66

Methods for making a supported iron-copper catalyst  

DOEpatents

A catalyst is described for the synthesis of hydrocarbons from CO+H.sub.2 utilizing a porous Al.sub.2 O.sub.3 support impregnated with iron and copper and optionally promoted with an alkali metal. The use of an Al.sub.2 O.sub.3 support results in the suppression of heavy waxes (C.sub.26 + hydrocarbons), particularly in slurry phase operation, when compared to unsupported or co-precipitated catalysts.

Dyer, Paul N. (Allentown, PA); Pierantozzi, Ronald (Macungie, PA)

1986-01-01

67

Iron oxide-copper-gold deposits: an Andean view  

Microsoft Academic Search

Iron oxide-copper-gold (IOCG) deposits, defined primarily by their elevated magnetite and\\/or hematite contents, constitute a broad, ill-defined clan related to a variety of tectono-magmatic settings. The youngest and, therefore, most readily understandable IOCG belt is located in the Coastal Cordillera of northern Chile and southern Peru, where it is part of a volcano-plutonic arc of Jurassic through Early Cretaceous age.

Richard H. Sillitoe

2003-01-01

68

Effect of copper and cadmium ions on heart function and calpain activity in blue mussel Mytilus edulis  

Microsoft Academic Search

The heart rate and calpain activity of blue mussels Mytilus edulis from the sublittoral zone, exposed to different levels of water-borne copper and cadmium, was investigated in a long-term experiment. The content of cadmium and copper in the blue mussel was determined using flame and graphite Atomic absorption spectroscopy. The observed concentrations ranged from 2.5 to 89.1 ?g\\/g dry weight

Igor N. Bakhmet; Nadezhda P. Kantserova; Liudmila A. Lysenko; Nina N. Nemova

2012-01-01

69

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

70

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

71

Changes in Selenium, Copper, Cadmium, and Zinc Concentrations in Mullet (Mugil cephalus) from the Southern Basin of Lake Macquarie, Australia, in  

E-print Network

Changes in Selenium, Copper, Cadmium, and Zinc Concentrations in Mullet (Mugil cephalus) from Abstract. Selenium, copper, cadmium, and zinc concentrations were measured in mullet (Mugil cephalus) from concentrations in mullet tissues. Mean muscle tissue concentrations of selenium (5.9 0.7 g/g dry mass), copper (3

Canberra, University of

72

Iron Acquisition by Phytosiderophores Contributes to Cadmium Tolerance1[OA  

PubMed Central

Based on the ability of phytosiderophores to chelate other heavy metals besides iron (Fe), phytosiderophores were suggested to prevent graminaceous plants from cadmium (Cd) toxicity. To assess interactions between Cd and phytosiderophore-mediated Fe acquisition, maize (Zea mays) plants were grown hydroponically under limiting Fe supply. Exposure to Cd decreased uptake rates of 59Fe(III)-phytosiderophores and enhanced the expression of the Fe-phytosiderophore transporter gene ZmYS1 in roots as well as the release of the phytosiderophore 2?-deoxymugineic acid (DMA) from roots under Fe deficiency. However, DMA hardly mobilized Cd from soil or from a Cd-loaded resin in comparison to the synthetic chelators diaminetriaminepentaacetic acid and HEDTA. While nano-electrospray-high resolution mass spectrometry revealed the formation of an intact Cd(II)-DMA complex in aqueous solutions, competition studies with Fe(III) and zinc(II) showed that the formed Cd(II)-DMA complex was weak. Unlike HEDTA, DMA did not protect yeast (Saccharomyces cerevisiae) cells from Cd toxicity but improved yeast growth in the presence of Cd when yeast cells expressed ZmYS1. When supplied with Fe-DMA as a Fe source, transgenic Arabidopsis (Arabidopsis thaliana) plants expressing a cauliflower mosaic virus 35S-ZmYS1 gene construct showed less growth depression than wild-type plants in response to Cd. These results indicate that inhibition of ZmYS1-mediated Fe-DMA transport by Cd is not related to Cd-DMA complex formation and that Cd-induced phytosiderophore release cannot protect maize plants from Cd toxicity. Instead, phytosiderophore-mediated Fe acquisition can improve Fe uptake in the presence of Cd and thereby provides an advantage under Cd stress relative to Fe acquisition via ferrous Fe. PMID:17337530

Meda, Anderson R.; Scheuermann, Enrico B.; Prechsl, Ulrich E.; Erenoglu, Bulent; Schaaf, Gabriel; Hayen, Heiko; Weber, Gunther; von Wiren, Nicolaus

2007-01-01

73

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

74

Arsenic, Cadmium, Copper, Lead, and Selenium in Migrating Blue-Winged Teal ( Anas discors L.)  

Microsoft Academic Search

The blue-winged teal (Anas discors L.), an abundant waterfowl species in North America, winters primarily in Mexico, Central America, and South America. Its\\u000a transcontinental migratory behavior provides the opportunity to examine contaminant acquisition across a diverse biogeographic\\u000a landscape that has varied environmental regulations and wildlife laws. We determined concentrations of arsenic (As), cadmium\\u000a (Cd), copper (Cu), lead (Pb), and selenium

A. M. Fedynich; B. M. Ballard; T. J. McBride; J. A. Estrella; J. M. Garvon; M. J. Hooper

2007-01-01

75

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

76

Combined toxicity of copper and cadmium to six rice genotypes ( Oryza sativa L.)  

Microsoft Academic Search

Accumulations of copper (Cu) and cadmium (Cd) in six rice cultivars (94D-22, 94D-54, 94D-64, Gui630, YY-1, and KY1360) were evaluated through exposure to heavy metal contamination (100 mg\\/kg Cu, 1.0 mg\\/kg Cd, and 100 mg\\/kg Cu + 1.0 mg\\/kg Cd) in a greenhouse. The dry weights of shoot and root, concentrations of Cu and Cd in plant tissues and the

Yizong HUANG; Ying HU; Yunxia LIU

2009-01-01

77

Biosorption of lead, copper and cadmium by biomass of Pseudomonas aeruginosa PU21  

Microsoft Academic Search

In this study, the biosorption kinetics of lead (Pb), copper (Cu) and cadmium (Cd) ions on the biomass of Pseudomonas aeruginosa PU21 (Rip64) was investigated. Effects of environmental factors and growth conditions on the biosorption were studied. Efficiency of metal ion recovery from metal-loaded biomass and subsequent regeneration of the biosorbent were also determined. The results show that, at pH

Jo-Shu Chang; Robin Law; Chung-Cheng Chang

1997-01-01

78

Bile secretion of cadmium, silver, zinc and copper in the rat. Involvement of various transport systems  

Microsoft Academic Search

In the present study we compared, in vivo in rats, the hepatobiliary transport of monovalent (silver:Ag) and divalent metals (zinc:Zn; cadmium:Cd) with that of copper (Cu). Cu can have two oxidation states in vivo, i.e. Cu(I) and Cu(II). Studies were performed in normal Wistar (NW) rats and mutant GY Wistar rats. The latter express defective canalicular ATP-dependent glutathione-conjugate transport (cMOAT);

Marjan Dijkstra; Rick Havinga; Roel J. Vonk; Folkert Kuipers

1996-01-01

79

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

Microsoft Academic Search

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

A. Karam; A. Jaouich

2009-01-01

80

Thermodynamics of ion association. Part XXIII. Copper, zinc, and cadmium complexes of some dipeptides  

Microsoft Academic Search

Calorimetric and potentiometric studies have been made at 25°C of the formation of zinc and cadmium complexes of diglycine and of the copper complexes of glycylsarcosine, glycineamide, glycylproline, glycyl-l-alanine, a-alanylglycine, and glycyl-?-aminobutyric acid. In addition, a potentiometric investigation has been made of the formation of copperl-alanyl-l-alanine complexes. The data have been used to calculate ?G, ?H, and ?S values for

A. P. Brunetti; E. J. Burke; M. C. Lim; G. H. Nancollas

1972-01-01

81

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

82

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 PMID:16666274

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

1988-01-01

83

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

84

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

85

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

86

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. PMID:24739807

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

2014-01-01

87

Structure and reactivity of copper-zinc-cadmium chromite catalysts  

Microsoft Academic Search

Different mixed oxides containing Cu, Zn, Cd and Cr were obtained by heating hydroxycarbonate precursors at various temperatures and in different atmospheres, and characterized by using X-ray diffraction (XRD), infrared, diffuse reflectance spectroscopy, thermogravimetry, and BET and copper surface area analysis. The reduction process and the phase evolution during reduction of the mixed oxides was followed by temperature-programmed reduction and

G. L. Castiglioni; A. Vaccari; G. Fierro; M. Inversi; M. Lo Jacono; G. Minelli; I. Pettiti; P. Porta; M. Gazzano

1995-01-01

88

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

89

Removal of copper and cadmium from the aqueous solutions by activated carbon derived from Ceiba pentandra hulls.  

PubMed

Activated carbon prepared from Ceiba pentandra hulls, an agricultural solid waste by-product, for the removal of copper and cadmium from aqueous solutions has been studied. Parameters such as equilibrium time, effect of pH and adsorbent dose on removal were studied. The adsorbent exhibited good sorption potential for copper and cadmium at pH 6.0. C=O and S=O functional groups present on the carbon surface were the adsorption sites to remove metal ions from solution. The experimental data was analysed by both Freundlich and Langmuir isotherm models. The maximum adsorption capacity of copper and cadmium was calculated from Langmuir isotherm and found to be 20.8 and 19.5 mg/g, respectively. The sorption kinetics of the copper and cadmium have been analysed by Lagergren pseudo-first-order and pseudo-second-order kinetic models. The desorption studies were carried out using dilute hydrochloric acid solution and the effect of HCl concentration on desorption was also studied. Maximum desorption of 90% for copper and 88% for cadmium occurred with 0.2 M HCl. PMID:16191464

Rao, M Madhava; Ramesh, A; Rao, G Purna Chandra; Seshaiah, K

2006-02-28

90

Cadmium, zinc, copper, sodium and potassium concentrations in rooster and turkey semen and their correlation.  

PubMed

The purpose of this study was to assess concentration of selected elements (cadmium, zinc, copper, sodium and potassium) in rooster and turkey semen and to find possible correlations between these elements. Samples were analyzed on the atomic absorption spectrophotometer. The analysis of cadmium showed that the concentration in rooster is 9.06 +/- 7.70 and in turkey 4.10 +/- 3.59 microg/mL. In zinc 5.25 +/- 1.96 microg/mL in rooster and 3.70 +/- 1.26 microg/mL in turkey were detected. Higher concentration of copper was found in rooster semen (6.79 +/- 6.42 microg/mL) in comparison with turkey semen (4.29 +/- 5.43 microg/mL). The level of sodium (3.96 +/- 1.02 microg/mL; 3.14 +/- 0.85 microg/mL) and potassium (2.88 +/- 0.65 microg/mL; 3.42 +/- 1.41 microg/mL) was very similar in both species. Correlation analysis detected high positive correlation between cadmium and zinc (r = 0.701) in rooster and between sodium and potassium (r = 0.899) in turkey semen. PMID:18324544

Massanyi, Peter; Weis, Jan; Lukac, Norbert; Trandzik, Jozef; Bystricka, Judita

2008-04-01

91

Metal-Responsive Transcription Factors That Regulate Iron, Zinc, and Copper Homeostasis in Eukaryotic Cells  

Microsoft Academic Search

Iron, copper, and zinc are all essential nutrients. The elec- tron transfer properties of iron and copper are fundamental to processes such as respiration and photosynthesis. Zinc forms the catalytic center in numerous enzymes and has an important structural role in a wide range of proteins. However, all these metals can be toxic if their levels and distribution are not

Julian C. Rutherford; Amanda J. Bird

2004-01-01

92

Oxidoreductive coupling of thiols with aryl halides catalyzed by copper on iron.  

PubMed

Synthesis and utilization of a simple copper on iron catalyst in the coupling of aryl halides with thiols through disulfide intermediate is reported. The iron support of copper catalyst ensures reductive media for the coupling, allows easy removal of the metals by outer magnetic field and enables the recycling of the catalyst. PMID:21079878

Kovács, Szabolcs; Novák, Zoltán

2011-02-01

93

Selenium, Cadmium, Copper, and Zinc Concentrations in Sediments and Mullet (Mugil cephalus) from the Southern Basin of Lake Macquarie, NSW, Australia  

E-print Network

Selenium, Cadmium, Copper, and Zinc Concentrations in Sediments and Mullet (Mugil cephalus) from. Selenium, cadmium, copper, and zinc concentrations were measured in sediments and the tissues of mullet in surficial sediments are enriched in trace metals relative to background concentrations (selenium, 3

Canberra, University of

94

Detoxification Mechanism of Heavy Metals in Marine Mammals and Seabirds: Interaction of Selenium with Mercury, Silver, Copper, Zinc, and Cadmium in Liver  

Microsoft Academic Search

Subcellular distribution of mercury, selenium, silver, copper, zinc, and cadmium was determined in the liver of northern fur seals (Callorhinus ursinus), black-footed albatrosses (Diomedea nigripes), and Dall’s porpoises (Phocoenoides dalli). Mercury, selenium, and silver were preferentially accumulated in nuclear, lysosomal, and mitochondrial fraction with an increase in their hepatic concentrations, whereas copper, zinc, and cadmium were accumulated mainly in cytosol

T. Ikemoto; T. Kunito; H. Tanaka; N. Baba; N. Miyazaki; S. Tanabe

2004-01-01

95

Copper-dependent iron assimilation pathway in the model photosynthetic eukaryote Chlamydomonas reinhardtii.  

PubMed

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 byAtx1), and a copper-transporting ATPase. A cDNA, Fer1, encoding ferritin for iron storage also was identified. Expression analysis demonstrated that Fox1 and Ftrl 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. PMID:12455693

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

2002-10-01

96

Use of Azolla to assess toxicity and accumulation of metals from artificial and natural sediments containing cadmium, copper, and zinc  

SciTech Connect

The aquatic macrophyte Azolla mexicana was studied to determine if it could indicate toxicity and bioavailability of cadmium, copper, and zinc in sediments. Plants were exposed to metal-fortified artificial sediment and to natural sediment contaminated with tailings from a Superfund site near Deer Lodge, Montana. Dry weights (mass) of biomass were used to determine effects of the metal concentrations and tissue metals were measured to determine metal uptake from the sediments. Plants exposed to artificial sediments fortified with cadmium and copper showed the greatest reduction in dry mass while zinc showed the least. And, plants exposed to copper singly in artificial sediments lost both zinc and cadmium for their tissues. Plants exposed to metal-contaminated natural sediment developed necrotic and chlorotic tissue within 24 hours in 75% and 100% dilutions but significant effects (P < 0.0001) using dry mass were found as low as 3.13%.

Powell, G.M. [S.M. Stoller Corp., Boulder, CO (United States); Nimmo, D.W.R.; Flickinger, S.A.; Brinkman, S.F.

1998-12-31

97

Effect of cadmium on prenatal development and on tissue cadmium, copper, and zinc concentrations in rats  

SciTech Connect

Administration of 60 and 180 ppm Cd in the drinking water of female rats from Day 1 to Day 20 of gestation resulted in a pronounced accumulation of Cd in all organs examined with the highest increase in the intestinal wall. The copper concentration was decreased in the liver and in the intestine of females from both groups in a dose-dependent manner and in the blood of females given Cd (180 ppm). The zinc concentration was decreased only in the kidney and the intestine of females from the higher level group. The serum glucose level, hemoglobin, and hematocrit were not affected in maternal blood, but the hematocrit was reduced in fetal blood in the 60-ppm Cd group. The fetal body weight and length were decreased in both groups though litter size was not affected. The fetal growth retardation was not concomitant with an increase of Cd concentration or with a decrease of copper and zinc concentration in fetal organs. Cd concentration was not changed in the fetal brain, liver, and kidney and increased only in the gastrointestinal tract of fetuses from the 180-ppm Cd group. The zinc concentration was decreased in fetal liver in the 180-ppm group and in brain of fetuses from the 60-ppm Cd group. The copper concentration was decreased in the gastrointestinal tract and increased in kidney of fetuses from the higher level group.

Baranski, B.

1987-02-01

98

Hyperfine field and hyperfine anomalies of copper impurities in iron  

SciTech Connect

A new value for the hyperfine magnetic field of copper impurities in iron is obtained by combining resonance frequencies from experiments involving {beta}-NMR on oriented nuclei on {sup 59}Cu, {sup 69}Cu, and {sup 71}Cu with magnetic moment values from collinear laser spectroscopy measurements on these isotopes. The resulting value, i.e., B{sub hf}(CuFe) = -21.794(10) T, is in agreement with the value adopted until now but is an order of magnitude more precise. It is consistent with predictions from ab initio calculations. Comparing the hyperfine field values obtained for the individual isotopes, the hyperfine anomalies in Fe were determined to be {sup 59{Delta}69}=0.15(9)% and {sup 71{Delta}69}=0.07(11)%.

Golovko, V. V.; Wauters, F.; Breitenfeldt, M.; De Leebeeck, V.; Roccia, S.; Soti, G.; Tandecki, M.; Traykov, E.; Van Gorp, S.; Severijns, N. [Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Cottenier, S. [Center for Molecular Modeling, Ghent University, Technologiepark 903, B-9052 Zwijnaarde (Belgium); Zakoucky, D. [Nuclear Physics Institute, ASCR, CZ-250 68 Rez (Czech Republic)

2011-07-15

99

Hyperfine Field and Hyperfine Anomalies of Copper Impurities in Iron  

E-print Network

A new value for the hyperfine magnetic field of copper impurities in iron is obtained by combining resonance frequencies from experiments involving {\\beta}-NMR on oriented nuclei on 59-Cu, 69-Cu, and 71-Cu with magnetic moment values from collinear laser spectroscopy measurements on these isotopes. The resulting value, i.e., Bhf(CuFe) = -21.794(10) T, is in agreement with the value adopted until now but is an order of magnitude more precise. It is consistent with predictions from ab initio calculations. Comparing the hyperfine field values obtained for the individual isotopes, the hyperfine anomalies in Fe were determined to be 59{\\Delta}69=0.15(9)% and 71{\\Delta}69=0.07(11)%.

V. V. Golovko; F. Wauters; S. Cottenier; M. Breitenfeldt; V. De Leebeeck; S. Roccia; G. Soti; M. Tandecki; E. Traykov; S. Van Gorp; D. Zákoucký; N. Severijns

2011-07-29

100

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

101

Evidence of maternal copper and cadmium transfer in two live-bearing fish species.  

PubMed

We studied maternal transfer of an essential metal (copper) and a non-essential one (cadmium) in the live-bearing fishes Heterandria formosa and Gambusia affinis. The goals of this study were: (1) to determine whether metals are transferred from exposed females to their developing offspring; (2) to determine if this transfer differs between two fish species that differ in their degree of maternal provisioning during development; (3) to determine the duration of maternal metal transfer once females are no longer exposed; and (4) to determine whether copper and cadmium are transferred equivalently. We exposed gravid females to background levels (control) or 0.15 µM of metal for 10 days, and then transferred them to clean water. We allowed females to give birth to up to three broods, and then quantified metal levels in offspring born at least 3 days after the transfer. We detected maternal metal transfer for both metals and in both species. Offspring metal levels decreased as females spent more time in clean water. Similarly, metal levels were lower in later broods than in earlier ones. Maternal metal transfer was higher in H. formosa than in G. affinis. Our results constitute the first report of maternal metal transfer in live-bearing fishes, and show that developing embryos acquire both essential and non-essential metals from their mothers in both species. This shows that metal toxicity may be an issue for live-bearing fish in clean environments when the previous generation has encountered metal pollution. PMID:25194944

Cazan, Alfy Morales; Klerks, Paul L

2014-11-01

102

Derived reference doses for three compounds used in the photovoltaics industry: Copper indium diselenide, copper gallium diselenide, and cadmium telluride  

SciTech Connect

Polycrystalline thin-film photovoltaic modules made from copper indium diselenide (CIS), copper gallium diselenide (CGS), and cadmium telluride (CdTe) arc nearing commercial development. A wide range of issues are being examined as these materials move from the laboratory to large-scale production facilities to ensure their commercial success. Issues of traditional interest include module efficiency, stability and cost. More recently, there is increased focus given to environmental, health and safety issues surrounding the commercialization of these same devices. An examination of the toxicological properties of these materials, and their chemical parents is fundamental to this discussion. Chemicals that can present large hazards to human health or the environment are regulated often more strictly than those that are less hazardous. Stricter control over how these materials are handled and disposed can increase the costs associated with the production and use of these modules dramatically. Similarly, public perception can be strongly influenced by the inherent biological hazard that these materials possess. Thus, this report: presents a brief background tutorial on how toxicological data are developed and used; overviews the toxicological data available for CIS, CGS and CdTe; develops ``reference doses`` for each of these compounds; compares the reference doses for these compounds with those of their parents; discusses the implications of these findings to photovoltaics industry.

Moskowitz, P.D.; Bernholc, N.; DePhillips, M.P.; Viren, J.

1995-07-06

103

Subcellular partitioning of cadmium, copper, nickel and zinc in indigenous yellow perch ( Perca flavescens) sampled along a polymetallic gradient  

Microsoft Academic Search

Sub-cellular metal distributions were studied in indigenous yellow perch (Perca flavescens) collected from eight lakes located along a cadmium (Cd), copper (Cu), nickel (Ni) and zinc (Zn) concentration gradient. Ambient dissolved metal concentrations were measured to evaluate exposure and total hepatic metal concentrations were determined as a measure of metal bioaccumulation. Metal partitioning among potentially metal-sensitive fractions (cytosolic enzymes, organelles)

Anik Giguère; Peter G. C. Campbell; Landis Hare; Patrice Couture

2006-01-01

104

Blood Pressure in Relation to Biomarkers of Lead, Cadmium, Copper, Zinc, and Selenium in Men without Occupational Exposure to Metals  

Microsoft Academic Search

The interrelationship of blood lead (BPb), activity of ?-aminolevulinic acid dehydratase (ALAD), erythrocyte protoporphyrin (EP), blood cadmium (BCd), serum copper (SCu), serum zinc (SZn), serum selenium (SSe), hematocrit (Hct), body mass index (BMI), age, smoking habits, and alcohol consumption to blood pressure was examined in 154 Croatian male subjects 19–53 years of age. None of the subjects had been occupationally

Spomenka Telišman; Jasna Jurasovi?; Alica Pizent; Petar Cvitkovi?

2001-01-01

105

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

106

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...

107

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

108

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

109

Cadmium, Copper, Lead and Zinc Concentrations in Female and Embryonic Pacific Sharpnose Shark (Rhizoprionodon longurio) Tissues.  

PubMed

In this work we compared the cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) contents of muscle, liver and placenta of gestating females of the viviparous shark Rhizoprionodon longurio and of muscle, liver and umbilical cord of their respective embryos. The higher values of the essential Cu and Zn were in embryonic or embryo-related tissues (placenta and umbilical cord). Maternal muscle and liver had the highest values of Pb and Cd, respectively. There were significant direct correlations between the Zn and Cd concentrations of placenta and umbilical cord, as well as between maternal muscle and embryonic livers for Pb and Cd, but the relation between these tissues was inverse in the case of Zn. All correlations between the metal content of embryonic tissues and size of the embryos were negative, suggesting an inverse relation between the rate of mother-to-embryo metal transfer and embryonic growth. PMID:25151279

Frías-Espericueta, M G; Cardenas-Nava, N G; Márquez-Farías, J F; Osuna-López, J I; Muy-Rangel, M D; Rubio-Carrasco, W; Voltolina, D

2014-11-01

110

The diverse roles of FRO family metalloreductases in iron and copper homeostasis.  

PubMed

Iron and copper are essential for plants and are important for the function of a number of protein complexes involved in photosynthesis and respiration. As the molecular mechanisms that control uptake, trafficking and storage of these nutrients emerge, the importance of metalloreductase-catalyzed reactions in iron and copper metabolism has become clear. This review focuses on the ferric reductase oxidase (FRO) family of metalloreductases in plants and highlights new insights into the roles of FRO family members in metal homeostasis. Arabidopsis FRO2 was first identified as the ferric chelate reductase that reduces ferric iron-chelates at the root surface-rhizosphere interface. The resulting ferrous iron is subsequently transported across the plasma membrane of root epidermal cells by the ferrous iron transporter, IRT1. Recent work has shown that two other members of the FRO family (FRO4 and FRO5) function redundantly to reduce copper to facilitate its uptake from the soil. In addition, FROs appear to play important roles in subcellular compartmentalization of iron as FRO7 is known to contribute to delivery of iron to chloroplasts while mitochondrial family members FRO3 and FRO8 are hypothesized to influence mitochondrial metal ion homeostasis. Finally, recent studies have underscored the importance of plasma membrane-localized ferric reductase activity in leaves for photosynthetic efficiency. Taken together, these studies highlight a number of diverse roles for FROs in both iron and copper metabolism in plants. PMID:24711810

Jain, Anshika; Wilson, Grandon T; Connolly, Erin L

2014-01-01

111

Impairment of Interrelated Iron- and Copper Homeostatic Mechanisms in Brain Contributes to the Pathogenesis of Neurodegenerative Disorders  

PubMed Central

Iron and copper are important co-factors for a number of enzymes in the brain, including enzymes involved in neurotransmitter synthesis and myelin formation. Both shortage and an excess of iron or copper will affect the brain. The transport of iron and copper into the brain from the circulation is strictly regulated, and concordantly protective barriers, i.e., the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (CSF) barrier (BCB) have evolved to separate the brain environment from the circulation. The uptake mechanisms of the two metals interact. Both iron deficiency and overload lead to altered copper homeostasis in the brain. Similarly, changes in dietary copper affect the brain iron homeostasis. Moreover, the uptake routes of iron and copper overlap each other which affect the interplay between the concentrations of the two metals in the brain. The divalent metal transporter-1 (DMT1) is involved in the uptake of both iron and copper. Furthermore, copper is an essential co-factor in numerous proteins that are vital for iron homeostasis and affects the binding of iron-response proteins to iron-response elements in the mRNA of the transferrin receptor, DMT1, and ferroportin, all highly involved in iron transport. Iron and copper are mainly taken up at the BBB, but the BCB also plays a vital role in the homeostasis of the two metals, in terms of sequestering, uptake, and efflux of iron and copper from the brain. Inside the brain, iron and copper are taken up by neurons and glia cells that express various transporters. PMID:23055972

Skj?rringe, Tina; M?ller, Lisbeth Birk; Moos, Torben

2012-01-01

112

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

113

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

114

Grain refinement of copper by the addition of iron and by electromagnetic stirring  

NASA Astrophysics Data System (ADS)

The effect of iron additions in the range of 0.57 to 7.5 wt pet on the grain size of electromagnetically levitated copper-iron alloys was investigated. The samples were solidified while levitated or quenched in water from the molten state. The addition of iron was found to be effective in reducing the grain size of copper, and the average grain size decreased as the iron content was increased up to the peritectic liquid composition of about 2.8 wt pet Fe. Beyond this composition, the grain size of the samples solidified in the levitated state was insensitive to the iron content, whereas that of the quenched samples continuously decreased with increasing iron content. The results indicate that electromagnetic stirring causes fragmentation of copper dendrites in the hypoperitectic region, and hence enhances grain refinement. In the hyperperitectic region, on the other hand, the stirring has a detrimental effect on the grain refinement by agglomerating the primary iron particles which act as heterogeneous nucleation sites for the copper matrix.

Patchett, J. A.; Abbaschian, G. J.

1985-09-01

115

Iron, copper and zinc isotopic fractionation up mammal trophic chains  

NASA Astrophysics Data System (ADS)

There is a growing body of evidence that some non-traditional elements exhibit stable isotope compositions that are distinct in botanical and animal products, providing potential new tracers for diet reconstructions. Here, we present data for iron (Fe), copper (Cu) and zinc (Zn) stable isotope compositions in plants and bones of herbivores and carnivores. The samples come from trophic chains located in the Western Cape area and in the Kruger National Park in South Africa. The Fe, Cu and Zn isotope systematics are similar in both parks. However, local Cu, and possibly Zn, isotopic values of soils influence that of plants and of higher trophic levels. Between plants and bones of herbivores, the Zn isotope compositions are 66Zn-enriched by about 0.8‰ whereas no significant trophic enrichment is observed for Fe and Cu. Between bones of herbivores and bones of carnivores, the Fe isotope compositions are 56Fe-depleted by about 0.6‰, the Cu isotope compositions are 65Cu-enriched by about 1.0‰, and the Zn isotope compositions are slightly 66Zn-depleted by about 0.2‰. The isotopic distributions of the metals in the body partly explain the observed trophic isotopic systematics. However, it is also necessary to invoke differential intestinal metal absorption between herbivores and carnivores to account for the observed results. Further studies are necessary to fully understand how the Fe, Cu and Zn isotope values are regulated within the ecosystem's trophic levels, but the data already suggests significant potential as new paleodietary and paleoecological proxies.

Jaouen, Klervia; Pons, Marie-Laure; Balter, Vincent

2013-07-01

116

Effects of cadmium, copper and zinc on growth of four isolated algae from a highly polluted Argentina river.  

PubMed

Toxicity of cadmium, copper and zinc was tested on four green algal species (Ankistrodesmus fusiformis, Chlorella ellipsoidea, Monoraphidium contortum and Scenedesmus acuminatus) isolated from a highly polluted river (Matanza-Riachuelo River, Buenos Aires, Argentina). The relative abundance of these species in river waters showed that C. ellipsoidea was the most abundant species (mean 4,540 ind mL(-1)), whereas the less abundant species was S. acuminatus (mean 220 ind mL(-1)). The most sensitive species was A. fusiformis, which EC50 were Cd = 141 ?g L(-1), Cu = 72 ?g L(-1), and Zn = 199 ?g L(-1), whereas C. ellipsoidea was the most resistant species to copper (EC50 = 489 ?g L(-1)) and cadmium (EC50 = 429 ?g L(-1)), and M. contortum and S. acuminatus were the most resistant species to zinc (EC50 = 381 and 394 ?g L(-1), respectively). PMID:24297640

Magdaleno, Anahí; Vélez, Carlos Guillermo; Wenzel, María Teresa; Tell, Guillermo

2014-02-01

117

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

118

Evolution of Microstructures During Austempering of Ductile Irons Alloyed with Manganese and Copper  

NASA Astrophysics Data System (ADS)

The influences of relatively high manganese (0.45 through 1.0 wt pct) and copper (0.56 through 1.13 wt pct) contents on microstructure development and phase transformation in three austempered ductile irons have been studied. The experimental ductile irons alloyed with copper and manganese are found to be practically free from intercellular manganese segregation. This suggests that the positive segregation of manganese is largely neutralized by the negative segregation of copper when these alloying elements are added in appropriate proportions. The drop in unreacted austenite volume (UAV) with increasing austempering temperature and time is quite significant in irons alloyed with copper and manganese. The ausferrite morphology also undergoes a transition from lenticular to feathery appearance of increasing coarseness with the increasing austempering temperature and time. SEM micrographs of the austempered samples from the base alloy containing manganese only, as well as copper plus manganese-alloyed irons, clearly reveal the presence of some martensite along with retained austenite and ferrite. X-ray diffraction analysis also confirms the presence of these phases. SEM examination further reveals the presence of twinned martensite in the copper plus manganese-alloyed samples. The possibility of strain-induced transformation of austenite to martensite during austempering heat treatment is suggested.

Dasgupta, Ranjan Kumar; Mondal, Dipak Kumar; Chakrabarti, Ajit Kumar

2013-03-01

119

TOXICITY OF CADMIUM AND COPPER AND THEIR EFFECT ON SOME BIOCHEMICAL PARAMETERS OF MARINE FISH MUGIL SEHELI  

Microsoft Academic Search

The present work aimed to estimate the toxicity of cadmium and copper to fingerlings of marine fish Mugil seheli, as well as the effect of different concentratios of Cd and Cu on some biochemical parameters (Aspartate and alanine transaminase enzymes, glucose, glycogen, lipid and protein) in the fish organs. 96-h LC50s of Cd and Cu were 5.36 and 1.64 ppm,

EMAD H. ABOU EL-NAGA; KHALID M. EL-MOSELHY; MOHAMED A. HAMED

120

Urinary excretion of copper, zinc and iron with and without D-penicillamine administration in relation to hepatic copper concentration in dogs.  

PubMed

Hereditary copper-associated hepatitis in dogs resembles Wilson's disease, a copper storage disease in humans. Values for urinary copper excretion are well established in the diagnostic protocol of Wilson's disease, whereas in dogs these have not been evaluated. The objectives of this study were to characterize both basal and D-penicillamine induced urinary copper, zinc and iron excretion in dogs in relation to hepatic copper concentration. Beagles, Beagle-Bedlington terrier cross-breeds homozygous for the COMMD1 gene mutation that causes copper toxicosis, and Labrador retrievers with normal or increased hepatic copper concentrations were investigated. The hepatic copper phenotype was determined by histological evaluation of liver biopsies and measurement of the hepatic copper concentration by instrumental neutron activation analysis. Urinary excretion of copper, iron and zinc was measured via inductively coupled plasma optical emission spectrometry under basal conditions and after oral administration of a single dose (20mg/kg bodyweight) of the chelator D-penicillamine. There was a rapid increase in urinary excretion of copper and zinc, but not iron after D-penicillamine administration. This increase was not different between dogs with high or normal hepatic copper concentrations. D-penicillamine-induced urinary copper excretion and the copper/creatinine ratio did not correlate with hepatic copper concentrations in the dogs studied, although basal urinary copper/zinc ratios did correlate with hepatic copper concentrations in Labrador retrievers. The latter parameter may be useful in diagnostic and follow-up protocols for copper-associated hepatitis in Labrador retrievers. PMID:23583003

Fieten, H; Hugen, S; van den Ingh, T S G A M; Hendriks, W H; Vernooij, J C M; Bode, P; Watson, A L; Leegwater, P A J; Rothuizen, J

2013-08-01

121

Seasonal variations in the concentrations of cadmium, copper, lead and zinc in leaves of the horse chesnut (Aesculus hippocastanum L.).  

PubMed

The concentrations of cadmium, copper, lead and zinc have been measured in the leaves of a deciduous tree the horse chestnut (Aesculus hippocastanum L.) over the period of their lifetime (7 months). The average concentrations for the total sample based on ash weight are: (microg g(-1)) cadmium, 0.197; copper, 129; lead, 294; and zinc, 299. The temporal trends in the concentrations of the metals can be related to their dominant source. Copper and zinc concentrations are highest in the new leaves and decrease with time, suggesting the main source of the elements are uptake from the soil. The decrease occurs partly because of dilution by leaf material as it increases over the growing period. In the case of zinc, however, aerial deposits appear to be also a significant source. Lead concentrations, on the other hand, show an increase with time, which can be related to increasing deposits from aerosol lead arising from the combustion of petrol lead. The increase is enough to offset the dilution effect. For cadmium there is no significant trend, but the tendency is a decrease with time. It is not possible, however, to distinguish between soil uptake and aerial deposit as both are small compared with increase in leaf material. PMID:15091650

Kim, N D; Fergusson, J E

1994-01-01

122

Some new chromogens for iron, cobalt, and copper Substituted hydrazidines and 1,2,4-triazines containing the ferroin group.  

PubMed

The spectral characteristics and solution conditions requisite for formation of the iron(II), cobalt(II), and copper(I) complexes of some newly synthesised compounds containing the ferroin functional grouping have been determined. These properties are useful for evaluation of the possible analytical effectiveness of the compounds as spectrophotometric reagents for the determination of iron, cobalt, and copper. PMID:18959951

Schilt, A A

1966-07-01

123

77 FR 36980 - Migratory Bird Hunting; Application for Approval of Copper-Clad Iron Shot as Nontoxic for...  

Federal Register 2010, 2011, 2012, 2013

...FF09M21200-123-FXMB1231099BPP0L2] RIN 1018-AY61 Migratory Bird Hunting; Application for Approval of Copper-Clad Iron Shot as Nontoxic for Waterfowl Hunting AGENCY: Fish and Wildlife Service, Interior...copper and iron as nontoxic for waterfowl hunting in the United States. The shot...

2012-06-20

124

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

125

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. PMID:24351714

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

2013-01-01

126

Strength and elasticity of iron and copper at high shock-wave compression pressures  

Microsoft Academic Search

The elastic and strength parameters of iron and copper were determined experimentally at high shock-wave compression pressures of 1–2 Mbar. The attenuation of shock waves created by the impact of thin plates in blocks of the investigated materials was recorded in the experiments. The Poisson ratios, bulk moduli, shear moduli, and yield strength Y for iron at 1.11 and 1.85

L. V. Al'tshuler; M. I. Brazhnik; G. S. Telegin

1971-01-01

127

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

128

Heavy metals zinc, cadmium, and copper stimulate pulmonary sensory neurons via direct activation of TRPA1.  

PubMed

Airway exposure to zinc dust and zinc-containing ambient particulates can cause symptoms of airway irritation and inflammation, but the underlying molecular and cellular mechanisms are largely unknown. Transient receptor potential A1 (TRPA1) is selectively expressed in a subpopulation of pulmonary C-fiber afferents and has been considered as a major irritant sensor in the lung and airways. Using whole cell patch-clamp recording and Ca(2+) imaging, we have demonstrated that application of ZnCl(2) concentration dependently evoked inward current and Ca(2+) transient in isolated vagal pulmonary sensory neurons; both responses were almost completely inhibited after pretreatment with AP18, a specific TRPA1 antagonist. In anesthetized spontaneously breathing animals, intratracheal instillation of ZnCl(2) (2 mM, 25 microl) induced pronounced respiratory depression in wild-type mice, and the effect was essentially absent in TRPA1-deficient mice. In addition, our study showed that two other heavy metals, cadmium and copper, also stimulated pulmonary sensory neurons via a direct activation of TRPA1. In summary, our results suggest that activation of TRPA1 in pulmonary C-fiber sensory nerves may contribute to the respiratory toxicity induced by airway exposure to these three heavy metals. PMID:20133428

Gu, Qihai; Lin, Ruei-Lung

2010-04-01

129

Determination and Evaluation of Cadmium, Copper, Nickel, and Zinc in Agricultural Soils of Western Macedonia, Greece  

NASA Astrophysics Data System (ADS)

The objective of this study was to determine the levels of major phytotoxic metals?including cadmium (Cd), copper (Cu), nickel (Ni), and zinc (Zn)?in agricultural soils of Western Macedonia, Greece. We also wanted to determine the possible relationships among elements and between soil properties and elemental concentrations. Surface soil samples, n = 570, were collected and analyzed. The results of the elemental analysis showed that the mean metal concentrations were consistent with reported typical concentrations found in Greek agricultural soils in the cases of Zn and Cu. Cd exhibited lower and Ni higher mean concentrations than the typical levels reported in the literature. Metal concentrations in the majority of the examined samples (>69%) were found to be higher than the respective critical plant-deficiency levels. However, only 0.4% and 0.2% of the analyzed soil samples, respectively, exhibited Cd and Ni concentrations higher than the levels that cause plant toxicity, as referenced by other investigators. These results suggest that the soils studied can be considered as unpolluted with respect to the examined food-chain metal contaminants. However, the levels of the metal concentrations in some of the soil samples, and the low correlation of the metals with soil properties, suggest an anthropogenic rather that lithogenic origin.

Papadopoulos, A.; Prochaska, C.; Papadopoulos, F.; Gantidis, N.; Metaxa, E.

2007-10-01

130

Toxicological effect of joint cadmium selenium quantum dots and copper ion exposure on zebrafish.  

PubMed

Quantum dots (QDs) have strong adsorption capacity; therefore, their potential toxicity to aquatic organisms from the facilitated transport of other trace toxic pollutants when they coexist has received increasing interest. However, the impact of cadmium selenium (CdSe) QDs and copper ion (Cu(2+)) joint exposure on zebrafish (Danio rerio) embryo and larvae remains almost unknown. Therefore, the present study was performed to determine the developmental toxicities to zebrafish exposed to combined pollution with CdSe QDs (500 µg/L) and Cu(2+) (0, 0.1, 1, 10, and 100 µg/L CuC1(2)) compared with single exposure. Our findings for the first time revealed that: (1) QDs facilitated the accumulation of Cu(2+) in zebrafish; (2) QDs caused higher mortality, lower hatch rate, and more malformations of the exposed zebrafish; (3) junction, bifurcation, crossing, particles, and aggregation of the exposed FLI-1 transgenic zebrafish larvae can be observed; (4) embryo cell apoptosis appeared in the head and tail region; and (5) synergistic effects played an important role during joint exposure. These observations provide a basic understanding of CdSe QDs and Cu(2+) joint toxicity to aquatic organisms and suggest the need for additional research to identify the toxicological mechanism. PMID:22714141

Zhang, Wei; Sun, Xue; Chen, Lin; Lin, Kuang-Fei; Dong, Qiao-Xiang; Huang, Chang-Jiang; Fu, Rong-Bing; Zhu, Jiang

2012-09-01

131

Evidence of Common Cadmium and Copper Uptake Routes in Zebrafish Danio rerio.  

PubMed

Cadmium and copper accumulations in gills of zebrafish were measured during a 48 h exposure to 0.025 ?M (106)Cd and 0.05 or 0.5 ?M (65)Cu as a single metal or their mixtures. The gill transcript levels of genes involved in the transport of Cu (CTR1 and ATP7A), Na (NHE-2), Ca (ECaC), divalent metals (DMT1), and Zn (ZIP8) were also compared between treatments at 24 and 48 h. Cd uptake was significantly suppressed in the presence of Cu, indicating interaction between Cu and Cd at uptake sites, but Cu uptake was unaffected by Cd. The decrease in Cd accumulation rates in the presence of Cu was associated with an increase in transcript abundance of ECaC at 24 h and DMT1 at 48 h and a decrease in Zip8 transcript levels, all known as routes for Cd uptake. Fish exposed to 0.5 ?M (65)Cu show an increase in gill ATP7a transcript abundance, suggesting that Cu is removed from the gill and is transferred to other organs for detoxification. A reduction in gill CTR1 transcript abundance was observed during the Cu-Cd exposure; this may be a regulatory mechanism to reduce Cu loading if Cu is entering the gills by other uptake routes, such as ECaC and DMT1. PMID:25289693

Komjarova, I; Bury, N R

2014-11-01

132

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

133

Effects of mine drainage on the river hayle, cornwall a) factors affecting concentrations of copper, zinc and iron in water, sediments and dominant invertebrate fauna  

Microsoft Academic Search

Concentrations of copper, zinc and iron were measured in waters, sediments and invertebrates collected from the River Hayle. In river water at least 70% of copper and iron was associated with the ‘particulate’ fraction whereas 80% of zinc was in the ‘soluble’ form. Although total concentrations of zinc in water exceeded those of copper approximately ten fold, copper predominated over

Barbara E. Brown

1977-01-01

134

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

135

Lenticular nucleus hyperechogenicity in Wilson's disease reflects local copper, but not iron accumulation.  

PubMed

In patients with Wilson's disease (WD) transcranial brain sonography typically reveals areas of increased echogenicity (hyperechogenicity) of the lenticular nucleus (LN). Correlation with T2-hypointensity on magnetic resonance images suggested that LN hyperechogenicity in WD is caused by trace metal accumulation. Accumulation of both, copper and iron, in the brain of WD patients has been reported. The present study was designed to elucidate whether LN hyperechogenicity in WD reflects accumulation of copper or iron. Post-mortem brains of 15 WD patients and one non-WD subject were studied with ultrasonography in an investigator-blinded fashion. LN hyperechogenicity was measured planimetrically by manual tracing as well as using digitized image analysis. The putaminal copper content was determined in samples of 11 WD brains and the non-WD brains using inductively coupled plasma mass spectrometry, and iron content was assessed using flame atomic absorption spectroscopy. LN was normal on ultrasonography only in the non-WD brain, but abnormal (hyperechogenic) in all WD brains. Digitized image analysis measures of LN hyperechogenicity and, by trend, manual measures correlated with putaminal copper content (Pearson test; digitized: r = 0.77, p = 0.04; manual: r = 0.57, p = 0.051) but not with iron content (each, p > 0.18). LN hyperechogenicity measures were unrelated to age at death of patients, age at onset of WD, WD duration, age of brain specimen, serum copper or serum ceruloplasmin (each, p > 0.1). We conclude that LN hyperechogenicity in WD reflects copper, but not iron accumulation. Further studies are warranted to elucidate the use of transcranial brain sonography for monitoring therapeutic effects of chelating agents in WD patients. PMID:24615184

Walter, Uwe; Skowro?ska, Marta; Litwin, Tomasz; Szpak, Gra?yna Maria; Jab?onka-Salach, Katarzyna; Skoloudík, David; Bulska, Ewa; Cz?onkowska, Anna

2014-10-01

136

Metal passivity as mechanism of metal carcinogenesis: Chromium, nickel, iron, copper, cobalt, platinum, molybdenum  

Microsoft Academic Search

For the transition metals chromium, nickel, iron, copper, cobalt, platinum, and molybdenum, mechanisms of stable bonding in biochemistry (emphasis on carcinogenic mechanisms), chemistry, industrial chemistry, as well as epidemiological, occupational, orthopedic (implant devices) effects related to carcinogenesis, were reviewed. Hypothetically, the propensity to stable bonding (inertness), which ensures the metals’ performance capacity for consumers and industrial application, relates to their

Cornelia Richardson-Boedler

2007-01-01

137

Influence of vegetative cycle of asparagus ( Asparagus officinalis L.) on copper, iron, zinc and manganese content  

Microsoft Academic Search

The essential elements copper (Cu), iron (Fe), zinc (Zn) and manganese (Mn) were analyzed in fresh asparagus to determine the effects of the vegetative cycle of the plant on the micronutrient content. Asparagus samples were classified in two groups by diameter (14 mm). Asparagus from a sample group with the same diameter were divided into two portions (apical and basal)

M. A. Amaro-Lopez; G. Zurera-Cosano; R. Moreno-Rojas; R. M. Garcia-Gimeno

1995-01-01

138

The effect of iron and copper impurities on the wettability of sphalerite (110) surface.  

PubMed

The effect of impurities in the zinc sulfide mineral sphalerite on surface wettability has been investigated theoretically to shed light on previously reported conflicting results on sphalerite flotation. The effect of iron and copper impurities on the sphalerite (110) surface energy and on the water adsorption energy was calculated with the semi-empirical method modified symmetrically orthogonalized intermediate neglect of differential overlap (MSINDO) using the cyclic cluster model. The effect of impurities or dopants on surface energies is small but significant. The surface energy increases with increasing surface iron concentration while the opposite effect is reported for increasing copper concentration. The effect on adsorption energies is much more pronounced with water clearly preferring to adsorb on an iron site followed by a zinc site, and copper site least favorable. The theoretical results indicate that a sphalerite (110) surface containing iron is more hydrophilic than the undoped zinc sulfide surface. In agreement with the literature, the surface containing copper (either naturally or by activation) is more hydrophobic than the undoped surface. PMID:21462368

Simpson, Darren J; Bredow, Thomas; Chandra, Anand P; Cavallaro, Giuseppe P; Gerson, Andrea R

2011-07-15

139

Cadmium  

Microsoft Academic Search

\\u000a Cadmium is a Group lib element discovered in 1818 by Herman and Strohmeyer and named after the mythological hero Cadmus who\\u000a founded Thebes in Greece. It was first extracted commercially in 1886 in Silesia. Its atomic weight is 112.41 (with natural\\u000a isotopes ranging from 106 to 116). A soft, ductile, silver-white metal (described also as blue-white; Baud, 1962) with a

Michael J. Scoullos; Gerrit H. Vonkeman; Iain Thornton; Zen Makuch

140

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

141

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

142

Blood cadmium is elevated in iron deficient U.S. children: a cross-sectional study  

PubMed Central

Background Cadmium (Cd), a widespread environmental contaminant, and iron deficiency (ID), the most common nutrient deficiency in the world, are known risk factors for neurodevelopmental delays, as well as other disorders, in infants and children. Studies assessing the cumulative effects of these factors are lacking in children, despite concerns of increased uptake of metals in the presence of ID. Here we sought to determine if blood and urine Cd levels were elevated in ID children compared to non-ID children. Methods Data for 5224 children, aged 3–19 years, were obtained from the 1999–2002 NHANES. ID was defined as ?2 of 3 abnormal iron indicators (low serum ferritin [SF], high free erythrocyte protoporphyrin [FEP], low % transferrin saturation [TSAT]); ID anemia (IDA) was defined as ID plus low hemoglobin (Hgb). Logistic regression was used to evaluate associations between ID, IDA, and abnormal iron indicators and categories of blood and urine Cd. Results Adjusted odds of ID, IDA, low SF, and low TSAT were associated with increasing category of blood Cd but not urine Cd. Adjusted ORs (95% CI) for blood Cd ?0.5 ?g/L versus?iron indicators revealed that the observed associations were strongest in females aged 16–19 years. Conclusions Given their shared neurotoxic effects in children, and that many people live in areas with high burdens of both ID and Cd, more research into the complex relationships between nutrient deficiencies and environmental toxicants is vital. PMID:24373608

2013-01-01

143

Computational Benchmarking in Biomimetic Nickel, Copper, and Iron Complexes  

E-print Network

in the absence of experimental data. In this dissertation, such techniques serve to elucidate the observed reactivity or electronic character of both nickel and copper bound in square planar N?S? ligand fields, and of {Fe(NO)?} units, respectively. Nickel...

Brothers, Scott Michael

2012-02-14

144

Cloning and characterization of the HSP90 beta gene from Tanichthys albonubes Lin (Cyprinidae): effect of copper and cadmium exposure.  

PubMed

Heat shock protein 90 (HSP90) is a highly conserved molecular chaperone important in the maturation of a broad spectrum of proteins. In order to evaluate the effect of copper (Cu(2+)) and cadmium (Cd(2+)) on the expression of HSP90 from Tanichthys albonubes (designated TaHSP90), the full-length complementary DNA (cDNA) of TaHSP90 was cloned using reverse transcription PCR and rapid amplification of cDNA ends (RACE) techniques. A 2,687-bp sequence was sequenced and consisted of an open reading frame (ORF) of 2,181 bp encoding a polypeptide of 727 amino acids with five HSP90 family signatures. Homologous analysis revealed that TaHSP90 gene shared high similarity with other known HSP90 genes and belonged to HSP90? subtype. Fluorescent real-time quantitative PCR was used to examine the expression pattern of TaHSP90? mRNA in different tissues (liver, muscle, gill, fin, eye, ovary, intestine and brain), and the result indicated that TaHSP90? was widely expressed in all examined tissues at different levels. Sensitivity of TaHSP90? to copper and cadmium was examined by exposing fish to different concentrations of Cu(2+) (0, 13.50 and 27.00 ?g/L) and Cd(2+) (0, 1.15, 2.31 mg/L) for 24, 48, 72 and 96 h, respectively. The copper treatment induced TaHSP90? expression slight increase only at 24 and 48 h, while cadmium treatment caused slight down-regulation of TaHSP90? only 72 and 96 h. Our data suggest that the cloning and expression analysis of T. albonubes HSP90? gene provided useful molecular information of T. albonubes responses in stress conditions and potential ways to monitor the chronic stressors in T. albonubes culture environments. PMID:21915694

Liu, Haichao; Chen, Huihui; Jing, Jing; Ma, Xufa

2012-06-01

145

Stress-related physiological effects in fish exposed to combinations of copper and cadmium  

SciTech Connect

During waterborne exposure, heavy metals such as copper (Cu) and cadmium (Cd) are not only taken up by fish gills, but also exert their primary toxic effect on this tissue. When the adaptive responses of the animals are inadequate, symptoms of stress have been observed. Tolerance for toxicants depends on specific physiological and biochemical accommodation of this tissue, partly regulated hormonally by products from the pituitary-interrenal axis. Cortisol not only modulates bronchial ion mechanisms but also regulates intermediate metabolism. The hormone is released in response to various stressful stimuli, such as heavy metals, and has been put forward as a stress index. Despite the increasing knowledge about the toxic mechanisms of sublethal concentrations of either Cu or Cd for fish, little is known about the effects of combined Cu/Cd exposure. The potential toxic effects of mixtures of heavy metals for fish is a subject of growing interest. The present study was undertaken to investigate the effects on fish exposed during 6 days to sublethal waterborne Cu and Cd concentrations, singly and in combination. It is demonstrated that although Cu and Cd have metal-specific effects, the effects observed in combined Cu/Cd exposed fish were not simple additive or synergistic, as demonstrated by metal accumulation in organs, chloride cell numbers, active ion transport activities and plasma ion composition. For several of these parameters, more deleterious effects were observed in combined Cu/Cd exposed fish than could have been predicted from effects observed in single Cu or Cd exposed fish. Plasma cortisol levels were increased in Cu-exposed fish, but an increase was not observed in combined Cu/Cd exposed fish. It is argued that the absence of this cortisol response contributes to the inadequate reaction of the combined Cu/Cd exposed fish.

Pelgrom, S.M.G.J.; Lock, R.A.C.; Balm, P.H.M.; Bonga, S.E.W. [Univ. of Nijmegen (Netherlands). Dept. of Animal Physiology

1995-12-31

146

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. PMID:18054180

Wang, Dixin; Du, Xuqin; Zheng, Wei

2014-01-01

147

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

148

Cadmium, lead and their mixtures with copper: Paracentrotus lividus embryotoxicity assessment, prediction, and offspring quality evaluation.  

PubMed

The aim of this research was to assess the combined effects of three heavy metals (copper, lead, cadmium) on the fertilization and offspring quality of the sea urchin Paracentrotus lividus at EC50, NOEL, and EC1 concentrations. The observed data were compared with the predictions derived from approaches of Concentration Addition (CA) and Independent Action (IA) in order to evaluate the proper prediction of the observed mixture toxic effect. The P. lividus embryotoxicity of trace metals decreases as follows: Cu > Pb > Cd at all toxicity concentration tested. EC50 mixture revealed less toxic only than Cu; EC50 was 0.80 (± 0.07) mg/l, the offspring malformations were mainly P1 type (skeletal alterations) up to 20% mixture concentration, and P2 type from 70% concentration. The NOEL and EC1 mixtures evidenced that all compounds contribute to the overall toxicity, even if present at low concentrations: the former EC50 was 0.532 (± 0.058) mg/l and the latter was 1.081 (± 0.240) mg/l. The developmental defects observed were mainly P1 type in both mixtures. Both CA and IA models did not accurately predict mixture toxicity for EC50 and NOEL mixtures. Instead, EC1 mixture effects seemed well represented by the IA model. The protective action of the CA model, although quite accurate when applied to simple biological systems like algae and bacteria, but failed to represent the worst-case in this study with more complex organisms. It would be useful to introduce in the models one or more factors that take into account the complexity of these biological systems. PMID:20552397

Manzo, Sonia; Buono, Silvia; Cremisini, Carlo

2010-10-01

149

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

150

Zinc Pyrithione Inhibits Yeast Growth through Copper Influx and Inactivation of Iron-Sulfur Proteins?†  

PubMed Central

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.

2011-01-01

151

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

152

Procion Blue MX3G-Attached Microporous Poly(2-Hydroxyethyl Methacrylate) Membranes for Copper, Arsenic, Cadmium, and Mercury Adsorption  

Microsoft Academic Search

pHEMA membranes carrying 25.6 mmol Procion Blue MX-3G\\/m were used for removal of heavy metal ions (i.e., copper, arsenic, cadmium, and mercury) from aqueous media containing different amounts of these ions (0.1–4.5 mmol\\/L) and at different pH values (2.0–8.0). The maximum adsorption capacities of heavy metal ions onto Procion Blue MX-3G-attached membranes under noncompetitive conditions were 5.6 mmol\\/m for Cu(II),

AD?L DEN?ZL?; RIDVAN SAY; H. NUR TESTEREC?; M. YAKUP ARICA

1999-01-01

153

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

Chronic toxicity of cadmium, copper, lead, or zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) was evaluated in water-only exposures started with newly hatched larvae or approximately 1-mo-old juveniles. The 20% effect concentration (EC20) for cadmium from the sturgeon tests was higher than the EC20 from the trout tests, whereas the EC20 for copper, lead, or zinc for the sturgeon were lower than those EC20s for the trout. When the EC20s from the present study were included in compiled toxicity databases for all freshwater species, species mean chronic value for white sturgeon was in a relatively low percentile of the species sensitivity distribution for copper (9th percentile) and in the middle percentile for cadmium (55th percentile), zinc (40th percentile), or lead (50th percentile). However, the species mean chronic value for rainbow trout was in a high percentile for copper, lead, and zinc (?68th–82nd percentile), but in a low percentile for cadmium (23rd percentile). The trout EC20s for each of the 4 metals and the sturgeon EC20s for cadmium or lead were above US Environmental Protection Agency chronic ambient water quality criteria (AWQC) or Washington State chronic water quality standards (WQS), whereas the sturgeon EC20s for copper or zinc were approximately equal to or below the chronic AWQC and WQS. In addition, acute 50% effect concentrations (EC50s) for copper obtained in the first 4 d of the chronic sturgeon test were below the final acute value used to derive acute AWQC and below acute WQS for copper.

Wang, Ning; Ingersoll, Christopher G.; Dorman, Rebecca A.; Brumbaugh, William G.; Mebane, Christopher A.; Kunz, James L.; Hardesty, Douglas K.

2014-01-01

154

Cadmium and Nickel Adsorption and Uptake in Cattail as Affected by Iron and Manganese Plaque on the Root Surface  

Microsoft Academic Search

The effects of iron (Fe) and manganese (Mn) plaque on the adsorption and uptake of cadmium (Cd) and nickel (Ni) in cattail (Typha latifolia L.) were investigated in nutrient solution cultures under laboratory conditions. Seedlings with and without Fe or Mn plaque on the roots (induced with 15 µg mL Fe or Mn) were exposed to 0.2 and 0.8 µg

Z. H. Ye; K. C. Cheung; M. H. Wong

2003-01-01

155

Study of the effect of cadmium vapor on the intensity of copper spectral lines excited in a discharge with a hollow cathode  

Microsoft Academic Search

The investigations were performed with the following combinations of copper and cadmiumcompounds: Cu(N03) 2 + Cd(N03)2; Cu(N03) 2 + CdCI2; CuCI 2 + Cd(N03) 2 and CuCI 2 + CdCI 2. The copper concentration in the solution equaled 10 -4 %. We employed two methods for introducing the cadmium into the discharge zone of the hollow cathode. In the first

A. N. Rudnevskii; V. N. Muzgin; D. E. Maksimov

1987-01-01

156

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

157

Effects of pH on the toxicities of cadmium, copper, and zinc to steelhead trout (salmo gairdneri) (journal version)  

SciTech Connect

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 trout (Salmo gairdneri). LC50 values were calculated for 96- and 168-h exposure periods in waters of pH 4.7, 5.7, and 7.0. Test fish were significantly more tolerant of the metals at the lowest pH value than at higher pHs. The 96-h LC50 values at pH 4.7, 5.7, and 7.0 were 671, 97, and 66 micrograms/L for zinc, 66.0, 4.2 and 2.8 micrograms/L for copper, and 28.0, 0.7 and less than 0.5 micrograms/L for cadmium, respectively. The 168-h results were similar to the 96-h values. The results indicate that for the metals tested, toxicity is ameliorated in depressed pH waters over short exposure periods, such as may occur during snowmelt runoff. The possibility of hydrogen-ion interference with metal uptake is postulated.

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

1986-01-01

158

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, Éder 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

159

Iron release from transferrin induced by mixed ligand complexes of copper(II).  

PubMed

Copper(II) complexes CuL1L2 with the ligand pairs 3-phosphoglycerate (PG)/ethylenediamine (en), phosphoserine (PS)/ethylenediamine, phosphoserine/malonate (mal) are shown to be effective in inducing the release of both iron atoms from di-ferric transferrin (Fe2Tf; human serum transferrin) at pH 7.3 in 1 M NaCl at 25 degrees C. Half-times of the reaction with Cu(PG)(en)- were less than 1 min at 0.02 M concentration. The iron(III) products are polynuclear hydroxo complexes. There is weaker interaction with Cu(PS)4-2 and virtually none with Cu(serine)(en) nor Cu(PS)(2,2'-bipyridyl)-, revealing crucial effects of the combined ligand sphere including the phosphomonoester group. The results suggest that the release of iron from Fe2Tf, or from either monoferric transferrins, occurred due to the breakdown of the stability of iron binding in conjunction with the expulsion of the synergistic anion carbonate (or oxalate). The active copper(II) complexes are postulated to be models of membrane components that could liberate iron from transferrin succeeding its uptake at the receptor sites of cells. PMID:2490073

Glaus, M; Schneider, W

1989-01-01

160

Kinetics and deposit morphology of gold cemented on magnesium, aluminum, zinc, iron and copper from ammonium thiosulfate–ammonia solutions  

Microsoft Academic Search

The kinetics of gold cementation by magnesium aluminum, zinc, iron and copper at equal conditions as well as the morphology of cementation products and the dissolution of cementing agents were investigated. Both the effect of cementing agents on gold cementation rate and the dissolution of metals decrease in order Cu>Zn>Mg>Fe>Al. High dissolution of magnesium, zinc, iron and copper per mol

M. Karavasteva

2010-01-01

161

Arsenic, cadmium, copper, lead, and selenium in migrating blue-winged teal (Anas discors L.).  

PubMed

The blue-winged teal (Anas discors L.), an abundant waterfowl species in North America, winters primarily in Mexico, Central America, and South America. Its transcontinental migratory behavior provides the opportunity to examine contaminant acquisition across a diverse biogeographic landscape that has varied environmental regulations and wildlife laws. We determined concentrations of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), and selenium (Se) in liver samples of blue-winged teal migrating through southern Texas during autumn 1998 (n = 47) and spring 1999 (n = 46). Concentrations for As (range 0.006 to 0.22 microg/g wet weight [ww]), Cd (range 0.007 to 8.14 microg/g ww), and Pb (range 0.012 to 1.79 microg/g ww) were at background levels for birds, whereas Cu (8.1 to 227.3 microg/g ww) and Se (0.36 to 5.07 microg/g ww) were increased in several individuals. All 24 hatch-year (HY) blue-winged teal had detectable levels of Cd, Cu, Pb, and Se, and eight had detectable levels of As. A seasonal effect was found for Cd, in which the mean Cd concentration in autumn was lower (p < 0.015) than in spring. Comparisons between autumn-collected HY and autumn-collected after-hatch-year (AHY) blue-winged teal found the mean concentration of Cd was higher (p < 0.001) in AHY birds. A seasonal effect occurred for Cu, in which the mean concentration was higher (p < 0.001) in autumn than in spring. Comparisons between seasons using only AHY blue-winged teal found that the mean concentration of Cu was higher (p < 0.001) in autumn than in spring. No sex effects (p > 0.05) were found for the five elements examined. Results indicated that blue-winged teal were acquiring all five elements; that HY blue-winged teal were exposed to these elements in North America; and that increased Se concentrations in 15% of the 93-bird sample were at levels known to cause impairment in birds. PMID:17571203

Fedynich, A M; Ballard, B M; McBride, T J; Estrella, J A; Garvon, J M; Hooper, M J

2007-11-01

162

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. PMID:19309492

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

2009-01-01

163

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

164

The effects of oral contraceptive use on iron and copper concentrations in breast milk  

Microsoft Academic Search

Objective: To determine the effects of oral contraceptive (OC) treatment on maternal iron and copper metabolism during lactation.Design: Observational study.Setting: Private and public clinics in Brazil.Patient(s): Lactating mothers attending the family planning clinic of the University of Brasilia.Intervention(s): The OCs used were a combination pill (0.15 mg of levonorgestrel and 0.03 mg of ethinyl estradiol) and a minipill (0.35 mg

Jose G Dorea; Edina S Miazaki

1999-01-01

165

Plasma manganese, selenium, zinc, copper, and iron concentrations in patients with schizophrenia  

Microsoft Academic Search

A number of essential trace elements play a major role in various metabolic pathways. Selenium (Se), manganese (Mn), copper\\u000a (Cu), zinc (Zn), and iron (Fe) are essential trace elements that have been studied in many diseases, including autoimmune,\\u000a neurological, and psychiatric disorders. However, the findings of previous research on the status of trace elements in patients\\u000a with schizophrenia have been

Medaim Yanik; Abdurrahim Kocyigit; Hamdi Tutkun; Huseyin Vural; Hasan Herken

2004-01-01

166

Simultaneous determination of cobalt, copper, iron and vanadium in crude petroleum oils by HPLC  

Microsoft Academic Search

A method has been developed for the simultaneous formation and solvent extraction of cobalt (II), copper (II), iron (II) and vanadium (IV) complexes of bis (acetylpivalylmethane)ethylenediamine (H2APM2en) in methyl isobutyl ketone. The complexes are eluted from a reversed phase HPLC column with a mixture of methanol:water:acetonitrile and detection was at 260 nm. The method has been applied to the simultaneous

S. N. Lanjwani; K. P. Mahar; A. H. Channer

1996-01-01

167

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

168

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

169

Bioaccumulation of Cadmium, Copper and Zinc in some Tissues of Three Species of Marine Turtles Stranded Along the French Atlantic Coasts  

Microsoft Academic Search

Cadmium, copper and zinc have been analysed in some tissues and organs of Loggerhead, Kemp’s Ridley (only muscle for this species) and Leatherback turtles stranded along the Atlantic coasts of France. The pancreas analysed only in Leatherback turtles exhibited the highest metal concentrations, which is very surprising for an organ which does not play a role in the detoxification processes.

F Caurant; P Bustamante; M Bordes; P Miramand

1999-01-01

170

Effects of iron on Vitamin C/copper-induced hydroxyl radical generation in bicarbonate-rich water.  

PubMed

The aim of this study was to evaluate whether iron, like copper, could support Vitamin C mediated hydroxyl radical formation in bicarbonate-rich water. By using the hydroxyl radical indicator coumarin-3-carboxylic acid, we found that iron, in contrast to copper, was not capable to support Vitamin C induced hydroxyl radical formation. However, when 0.2 mg/l iron and 0.1 mg/l copper were both added to bicarbonate supplemented Milli-Q water, the Vitamin C induced formation of 7-hydroxycoumarin, as measured by HPLC analysis, was inhibited by 47.5%. The inhibition of hydroxyl radical formation by iron was also evident in the experiments performed on copper contaminated bicarbonate-rich household drinking water samples. In the presence of 0.2 mg/l of ferric iron the ascorbic acid induced hydroxyl radical formation was inhibited by 36.0-44.6%. This inhibition was even more significant, 47.0-59.2%, when 0.8 mg/l of ferric iron was present. None of the other redox-active metals, e.g. manganese, nickel or cobalt, could support ascorbic acid induced hydroxyl radical formation and did not have any impact on the ascorbic acid/copper-induced hydroxyl radical generation. Our results show, that iron cannot by itself produce hydroxyl radicals in bicarbonate rich water but can significantly reduce Vitamin C/copper-induced hydroxyl radical formation. These findings might partly explain the mechanism for the iron-induced protective effect on various copper related degenerative disorders that earlier has been observed in animal model systems. PMID:16036332

Jansson, Patric J; Del Castillo, Urko; Lindqvist, Christer; Nordström, Tommy

2005-05-01

171

Iron deficiency is associated with increased levels of blood cadmium in the Korean general population: Analysis of 2008-2009 Korean National Health and Nutrition Examination Survey data  

SciTech Connect

Introduction: We present data from the Korean National Health and Nutrition Examination Survey 2008-2009 on the distribution of blood cadmium levels and their association with iron deficiency in a representative sample of the adult Korean population. Methods: Serum ferritin was categorized into three levels: low (serum ferritin <15.0 {mu}g/L), low normal (15.0-30.0 {mu}g/L for women and 15.0-50.0 for men), and normal ({>=}30.0 {mu}g/L for women and {>=}50.0 for men), and its association with blood cadmium level was assessed after adjustment for various demographic and lifestyle factors. Results: Geometric means of blood cadmium in the low serum ferritin group in women, men, and all participants were significantly higher than in the normal group. Additionally, multiple regression analysis after adjusting for various covariates showed that blood cadmium was significantly higher in the low-ferritin group in women, men, and all participants compared with the normal group. We also found an association between serum ferritin and blood cadmium among never-smoking participants. Discussion: We found, similar to other recent population-based studies, an association between iron deficiency and increased blood cadmium in men and women, independent of smoking status. The results of the present study show that iron deficiency is associated with increased levels of blood cadmium in the general population.

Lee, Byung-Kook [Institute of Environmental and Occupational Medicine, Soonchunhyang University, 646 Eupnae-ri, Shinchang-myun, Asan-si, Choongnam 336-745 (Korea, Republic of)] [Institute of Environmental and Occupational Medicine, Soonchunhyang University, 646 Eupnae-ri, Shinchang-myun, Asan-si, Choongnam 336-745 (Korea, Republic of); Kim, Yangho, E-mail: yanghokm@nuri.net [Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, 290-3 Cheonha-Dong, Dong-Gu, Ulsan 682-060 (Korea, Republic of)] [Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, 290-3 Cheonha-Dong, Dong-Gu, Ulsan 682-060 (Korea, Republic of)

2012-01-15

172

Comparison of the mineralogy of the Boss-Bixby, Missouri copper-iron deposit, and the Olympic Dam copper-uranium-gold deposit, South Australia  

Microsoft Academic Search

An ore microscopic examination of 80 polished sections prepared from selected drill core specimens from the Boss-Bixby, Missouri copper-iron deposit has shown that its mineral assemblage is similar to that of the Olympic Dam (Roxby Downs) copper-uranium-gold deposit in South Australia. A comparison with the mineralogy reported for Olympic Dam shows that both deposits contain: 1) the principal minerals, magnetite,

R. T. Brandom; R. D. Hagni; C. R. Allen

1985-01-01

173

Cadmium (Cd(2+)) removal by nano zerovalent iron: surface analysis, effects of solution chemistry and surface complexation modeling.  

PubMed

Nano zerovalent iron (nZVI) is an effective remediant for removing various organic and inorganic pollutants from contaminated water sources. Batch experiments were conducted to characterize the nZVI surface and to investigate the effects of various solution properties such as pH, initial cadmium concentration, sorbent dosage, ionic strength, and competitive ions on cadmium removal by nZVI. Energy-dispersive X-ray and X-ray photoelectron spectroscopy results confirmed removal of Cd(2+) ions by nZVI through adsorption. Cd(2+) adsorption decreased in the presence of competitive cations in the order: Zn(2+)?>?Co(2+)?>?Mg(2+)?>?Mn(2+)?=?Cu(2+)?>?Ca(2+)?>?Na(2+)?=?K(+). Higher concentrations of Cl(-) significantly decreased the adsorption. Cadmium removal increased with solution pH and reached a maximum at pH 8.0. The effects of various solution properties indicated Cd(2+) adsorption on nZVI to be a chemisorption (inner-sphere complexation) process. The three surface complexation models (diffuse layer model, constant capacitance model, and triple layer model) fitted well to the adsorption edge experimental data indicating the formation of nZVI-Cd bidentate inner-sphere surface complexes. Our results suggest that nZVI can be effectively used for the removal of cadmium from contaminated water sources with varying chemical conditions. PMID:23589245

Boparai, Hardiljeet K; Joseph, Meera; O'Carroll, Denis M

2013-09-01

174

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. PMID:24946800

2014-01-01

175

Environmental, health, safety, and regulatory review of selected photovoltaic options: Copper sulfide/cadmium sulfide and polycrystalline silicon  

NASA Astrophysics Data System (ADS)

Emissions, effluents and solid wastes from the fabrication of both polycrystalline silicon and front-wall copper sulfide/cadmium sulfide photovoltaic cells are summarized. Environmental, health, and safety characteristics of cell fabrication material inputs and by products are listed. Candidate waste stream treatment methods and resultant effluents are reviewed. Environmental, health, and safety effects of photovoltaic cell/module/array installation, operation, maintenance, and decommission are summarized. Federal legislation is addressed and future regulatory trends under these laws as they may affect each cell process are discussed. Water quality, solid waste disposal, and occupational health and safety regulations will likely be those most applicable to commercial scale PV production. Currently available control technology appears sufficient to treat cell fabrication wastes.

Lawrence, K.; Morgan, S.; Schaller, D.; Wilczak, T.

1981-06-01

176

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

177

Responses of seedling growth and antioxidant activity to excess iron and copper in Triticum aestivum L.  

PubMed

The purpose of this study was to analyze phytotoxicity mechanism involved in root growth and to compare physiological changes in the leaves of wheat seedlings exposed to short term iron (Fe) and copper (Cu) stresses (0, 100, 300 and 500?M). All applied Fe or Cu concentrations reduced root and shoot lengths, but seed germination was inhibited by Cu only at 500?M. Analyses using fluorescent dye 2',7'-dichlorodihydrofluorescein diacetate indicated enhanced H(2)O(2) levels in seedling roots under Fe and Cu treatments. Cu stress at the same concentration induced a great reduction in cell viability and a strong damage on membrane lipid in the roots with respect to Fe treatment. Significant increases in the total chlorophyll (chl) content including chl a and chl b were observed in response to higher Fe concentrations, whereas the highest Cu concentration (500?M) led to significant decreases in the total chl content including chl a. Additionally, leaf peroxidase (POD) and ascorbate peroxidase (APX) were stimulated by Fe stress, but the highest Fe concentration exhibited inhibitory effect on leaf APX activity. In contrast, copper treatment resulted in an elevation in leaf catalase and POD activities. Therefore, H(2)O(2) content in the leaves associated with copper was significantly lower than that with iron at the same concentration. PMID:23025893

Li, Xiaoning; Ma, Haizhen; Jia, Pengxiang; Wang, Juan; Jia, Lingyun; Zhang, Tengguo; Yang, Yingli; Chen, Haijian; Wei, Xia

2012-12-01

178

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

PubMed Central

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

179

National contaminant biomonitoring program: Concentrations of arsenic, cadmium, copper, lead, mercury, selenium, and zinc in U.S. Freshwater Fish, 1976–1984  

Microsoft Academic Search

From late 1984 to early 1985, the U.S. Fish and Wildlife Service collected a total of 315 composite samples of whole fish\\u000a from 109 stations nationwide, which were analyzed for arsenic, cadmium, copper, lead, mercury, selenium, and zinc. Geometric\\u000a mean, maximum, and 85th percentile concentrations (?g\\/g wet weight) for 1984 samples were as follows: arsenic-0.14, 1.5, 0.27;\\u000a cadmium-0.03, 0.22, 0.05;

Christopher J. Schmitt; William G. Brumbaugh

1990-01-01

180

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...

181

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

182

Determination of copper, scandium, molybdenum, tin, lead, and iron group elements in lunar surface materials  

NASA Technical Reports Server (NTRS)

Distribution regularities of copper, scandium, molybdenum, tin, lead, and iron group elements were investigated in basaltoid rocks of lunar and terrestrial origin. Samples of various regolith zones taken in the area of the Sea of Fertility were analyzed, along with samples of basic and ultrabasic rocks of the East African Rift for their content of the trace admixtures listed. Data obtained on the abundance of copper, scandium, molybdenum, tin, lead, cobalt, nickel, chromium, and vanadium in Luna 16 lunar surface material were compared with the abundance of these elements in samples of lunar rocks returned by Apollo 11, Apollo 12, and Apollo 14, with the exception of scandium; its content in the latter samples was considerably higher.

Pavlenko, L. I.; Simonova, L. V.; Karyakin, A. V.

1974-01-01

183

Manganese and iron oxide immobilized activated carbons precursor to dead biomasses in the remediation of cadmium-contaminated waters.  

PubMed

The aim of the present investigation was to exploit the high specific surface area of activated carbons in immobilizing the manganese and iron oxides as to obtain a suitable, efficient and cost effective and environment benign wastewater treatment process in the remediation of cadmium-contaminated waters. The manganese and iron oxides were impregnated in situ onto the surface and pores of the activated carbons precursors to the rice hulls and areca nut wastes. The solids were characterized with the help of Fourier transform infrared spectroscopy and X-ray diffraction analytical data, and the BET specific surface area as obtained. The surface morphology of these solids was discussed with the help of scanning electron microscopic images. The activated carbon samples along with the manganese and iron immobilized activated carbons were further employed in the batch and column reactor operations in the remediation of cadmium-contaminated waters. The batch data showed that an increase in sorptive pH from 2.0 to 10.0 and concentration from 1.0 to 20 mg/L favoured the uptake of cadmium by these solids. Moreover, the 1,000 times increase in background electrolyte concentrations NaNO3 caused an insignificant decrease in cadmium uptake by these solids, which inferred that sorbing ions/species were sorbed specifically and forming 'inner-sphere' complexes onto the solid surface. The concentration dependence data were utilized to model various adsorption isotherms and indicated that Freundlich adsorption isotherm was reasonably fitted well. The kinetic data was fitted well to the pseudo-second-order rate equations; hence, the equilibrium sorption capacity was estimated. Furthermore, the dynamic experiments carried out by the column experiments and the breakthrough data were fitted well to the non-linear Thomas equations; accordingly, the loading capacity of the column was estimated. Iron or manganese immobilized activated carbons showed relatively higher loading capacity compared to its precursor activated carbons hence showing its possible implication in the remediation processes. Moreover, among these modified ACs, IIAC showed higher removal capacity than the MIAC solid. PMID:23589235

Lee, Seung-Mok; Lalhmunsiama; Choi, Sang-Il; Tiwari, Diwakar

2013-10-01

184

Iron and Copper Act Synergistically To Delay Anaerobic Growth of Bacteria  

PubMed Central

Transition metals are known to cause toxic effects through their interaction with oxygen, but toxicity under anoxic conditions is poorly understood. Here we investigated the effects of iron (Fe) and copper (Cu) on the anaerobic growth and gene expression of the purple phototrophic bacterium Rhodopseudomonas palustris TIE-1. We found that Fe(II) and Cu(II) act synergistically to delay anaerobic growth at environmentally relevant metal concentrations. Cu(I) and Cu(II) had similar effects both alone and in the presence of ascorbate, a Cu(II) reductant, indicating that reduction of Cu(II) to Cu(I) by Fe(II) is not sufficient to explain the growth inhibition. Addition of Cu(II) increased the toxicity of Co(II) and Ni(II); in contrast, Ni(II) toxicity was diminished in the presence of Fe(II). The synergistic anaerobic toxicity of Fe(II) and Cu(II) was also observed for Escherichia coli MG1655, Shewanella oneidensis MR-1, and Rhodobacter capsulatus SB1003. Gene expression analyses for R. palustris identified three regulatory genes that respond to Cu(II) and not to Fe(II): homologs of cueR and cusR, two known proteobacterial copper homeostasis regulators, and csoR, a copper regulator recently identified in Mycobacterium tuberculosis. Two P-type ATPase efflux pumps, along with an FoF1 ATP synthase, were also upregulated by Cu(II) but not by Fe(II). An Escherichia coli mutant deficient in copA, cus, and cueO showed a smaller synergistic effect, indicating that iron might interfere with one or more of the copper homeostasis systems. Our results suggest that interactive effects of transition metals on microbial physiology may be widespread under anoxic conditions, although the molecular mechanisms remain to be more fully elucidated. PMID:23563938

Bird, Lina J.; Coleman, Maureen L.

2013-01-01

185

Iron and copper act synergistically to delay anaerobic growth of bacteria.  

PubMed

Transition metals are known to cause toxic effects through their interaction with oxygen, but toxicity under anoxic conditions is poorly understood. Here we investigated the effects of iron (Fe) and copper (Cu) on the anaerobic growth and gene expression of the purple phototrophic bacterium Rhodopseudomonas palustris TIE-1. We found that Fe(II) and Cu(II) act synergistically to delay anaerobic growth at environmentally relevant metal concentrations. Cu(I) and Cu(II) had similar effects both alone and in the presence of ascorbate, a Cu(II) reductant, indicating that reduction of Cu(II) to Cu(I) by Fe(II) is not sufficient to explain the growth inhibition. Addition of Cu(II) increased the toxicity of Co(II) and Ni(II); in contrast, Ni(II) toxicity was diminished in the presence of Fe(II). The synergistic anaerobic toxicity of Fe(II) and Cu(II) was also observed for Escherichia coli MG1655, Shewanella oneidensis MR-1, and Rhodobacter capsulatus SB1003. Gene expression analyses for R. palustris identified three regulatory genes that respond to Cu(II) and not to Fe(II): homologs of cueR and cusR, two known proteobacterial copper homeostasis regulators, and csoR, a copper regulator recently identified in Mycobacterium tuberculosis. Two P-type ATPase efflux pumps, along with an F(o)F(1) ATP synthase, were also upregulated by Cu(II) but not by Fe(II). An Escherichia coli mutant deficient in copA, cus, and cueO showed a smaller synergistic effect, indicating that iron might interfere with one or more of the copper homeostasis systems. Our results suggest that interactive effects of transition metals on microbial physiology may be widespread under anoxic conditions, although the molecular mechanisms remain to be more fully elucidated. PMID:23563938

Bird, Lina J; Coleman, Maureen L; Newman, Dianne K

2013-06-01

186

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

187

Simultaneous determination of iron and copper in children's sera by FAAS.  

PubMed

A new and simple flame atomic-absorption spectrometric (FAAS) method is proposed for simultaneous determination of iron and copper in children's sera. It is based on single-step sample pretreatment (deproteinization with 3 mol L-1 HCl, ratio 1:1) and single-step calibration using 1.5 mol L-1 HCl standard. During method's optimization a short multifactorial design experiment was used. The proposed method assures accuracy, sensitivity and precision comparable to that of the reference methods. The new approach is simple and time-, labour- and serum-saving, the latter being especially important in pediatric diagnostics. PMID:21406347

Luterotti, Svjetlana; Kordi?, Ton?ica Vukman; Dodig, Slavica

2011-03-01

188

Seasonal changes of zinc, copper, and iron in gilthead sea bream ( Sparus aurata ) fed fortified diets  

Microsoft Academic Search

Four groups of gilthead sea bream (Sparus aurata) were fed diets with additional metal contents: a basal diet (diet A) contained Zn at 60.9 ± 1.9 mg\\/kg diet, Cu at 3.9 ±\\u000a 0.9 mg\\/kg diet, and Fe at 138.3 ± 6.8 mg\\/kg diet; the other diets were supplemented with copper (20 mg\\/kg, diet B), iron (100\\u000a mg\\/kg, diet C), or

Emilio Carpeme; Rossella Serra; Maurizio Manera; Gloria Isani

1999-01-01

189

Leaching of antimony, cadmium, copper, lead, silver, tin and zinc prom copper piping with non?lead?based soldered joints  

Microsoft Academic Search

Studies were done on the leaching of Ag, Cd, Cu, Pb, Sb, Sn and Zn from 95\\/5 Sn\\/Sb?, 96\\/4 Sn\\/Ag?, 94\\/6 Sn\\/Ag?, and 95.5\\/4.0\\/0.5 Sn\\/Cu\\/Ag?soldered copper pipes into high?purity, tap, and well water samples as a function of standing time in a static test on new plumbing. There was no significant leaching of Ag, Cd, Pb, Sb and Sn from

K. S. Subramanian; J. W. Connor; J. C. Meranger

1991-01-01

190

Contact Killing of Bacteria on Copper Is Suppressed if Bacterial-Metal Contact Is Prevented and Is Induced on Iron by Copper Ions  

PubMed Central

Bacteria are rapidly killed on copper surfaces, and copper ions released from the surface have been proposed to play a major role in the killing process. However, it has remained unclear whether contact of the bacteria with the copper surface is also an important factor. Using laser interference lithography, we engineered copper surfaces which were covered with a grid of an inert polymer which prevented contact of the bacteria with the surface. Using Enterococcus hirae as a model organism, we showed that the release of ionic copper from these modified surfaces was not significantly reduced. In contrast, killing of bacteria was strongly attenuated. When E. hirae cells were exposed to a solid iron surface, the loss of cell viability was the same as on glass. However, exposing cells to iron in the presence of 4 mM CuSO4 led to complete killing in 100 min. These experiments suggest that contact killing proceeds by a mechanism whereby the metal-bacterial contact damages the cell envelope, which, in turn, makes the cells susceptible to further damage by copper ions. PMID:23396344

Mathews, Salima; Hans, Michael

2013-01-01

191

Content of trace metals (iron, zinc, manganese, chromium, copper, nickel) in canned variegated scallops (Chlamys varia).  

PubMed

This article presents the results obtained through a study of the concentration of trace metals (iron, zinc, manganese, chromium, copper, nickel) in some conserves of variegated scallops (Chlamys varia, Bivalvia, Mollusca). A total of 300 samples of seven different commercial brands (named A, B, D, H, J, L and M) and one processing type, 'scallop sauce', were analysed. Samples were collected weekly in a large shopping centre in Santa Cruz de Tenerife during a 12-month period. Variegated scallops have considerable concentrations of zinc, cupper and manganese, so that their dietary intake constitutes an important source of these metals. However, they have low concentrations of chrome and nickel, and the levels of iron are similar to those found in other bivalve molluscs. PMID:19086337

Gutiérrez, Angel J; González-Weller, Dailos; González, Tomás; Burgos, Antonio; Lozano, Gonzalo; Hardisson, Arturo

2008-09-01

192

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. PMID:23530765

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

2013-01-01

193

Age-associated changes of brain copper, iron, and zinc in Alzheimer's disease and dementia with lewy bodies.  

PubMed

Disease-, age-, and gender-associated changes in brain copper, iron, and zinc were assessed in postmortem neocortical tissue (Brodmann area 7) from patients with moderate Alzheimer's disease (AD) (n = 14), severe AD (n = 28), dementia with Lewy bodies (n = 15), and normal age-matched control subjects (n = 26). Copper was lower (20%; p < 0.001) and iron higher (10-16%; p < 0.001) in severe AD compared with controls. Intriguingly significant Group*Age interactions were observed for both copper and iron, suggesting gradual age-associated decline of these metals in healthy non-cognitively impaired individuals. Zinc was unaffected in any disease pathologies and no age-associated changes were apparent. Age-associated changes in brain elements warrant further investigation. PMID:25024342

Graham, Stewart F; Nasaruddin, Muhammad Bin; Carey, Manus; Holscher, Christian; McGuinness, Bernadette; Kehoe, Patrick G; Love, Seth; Passmore, Peter; Elliott, Christopher T; Meharg, Andrew A; Green, Brian D

2014-01-01

194

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. PMID:25027256

2014-01-01

195

Liquid chromatographic determination of chelates of cobalt (II), copper (II) and iron (II) with 2-thiophonaldehyde-4-phenyl-3-thiosemicarbazone  

Microsoft Academic Search

Summary  A new chelating reagent 2-thiophenaldehyde-4-phenyl-3-thiosemicarbazone (TAPT) has been examined for high performance liquid\\u000a chromatographic (HPLC) separations of cobalt (II), copper(II) and iron (II) or cobalt (II), nickel (II), iron (II), copper\\u000a (II) and mercury (II) as metal chelates on a C18, 5?m column (2504 mm i.d.) The chelates were eluted isocratically with methanol: acetonitrile: water containing sodium acetate\\u000a and tetrabutylammonium

Y. Zhao

2000-01-01

196

UltramicroAnalysisfor Copper, Cadmium,and Zinc in Human LiverTissueby Use of Atomic Absorption Spectrophotometryand the Heated GraphiteTube Atomizer  

Microsoft Academic Search

We describe a method of analysis for copper, cadmium, and zinc in a 15-mg (wet weight) sample of human liver by atomic absorption spectrophotometry. The sample is digested with nitric acid (1.0 mol\\/liter), evaporated, and dilute HNO3 (10 mmol\\/Iiter) added. The reconstituted acid mixture is injected into the graphite tube atomizer for analysis of Cu and Cd and aspirated into

Merle A. Evensonand; C. ThomasAnderson

1975-01-01

197

Simultaneous detection of cadmium, copper, and lead using a carbon paste electrode modified with carbamoylphosphonic acid self-assembled monolayer on mesoporous silica (SAMMS)  

Microsoft Academic Search

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 (SAM) on mesoporous silica (Ac-Phos SAMMS). The adsorptive stripping voltammetry (AdSV) technique involves preconcentration of the metal ions onto Ac-Phos SAMMS under an open circuit,

Wassana Yantasee; Yuehe Lin; Glen E. Fryxell; Brad J. Busche

2004-01-01

198

[Crosslinked carboxymethyl konjac glucomannan microcolumn preconcentration of trace lead, cadmium and copper in water samples and determination by graphite furnace atomic absorption spectrometry].  

PubMed

A novel solid phase extraction technique was developed for the determination of trace lead, cadmium and copper in environmental water samples based on separation and preconcentration with a microcolumn packed with crosslinked carboxymethyl konjac glucomannan (CCMKGM)prior to its determination by graphite furnace atomic absorption spectrometry. Various influential factors on the separation and preconcentration of lead, cadmium and copper, such as the acidity of the aqueous solution, sample flow rate and volume, and eluent concentration and volume, were investigated systematically, and the optimized operation conditions were established. The analytes could be quantitatively retained by CCMKGM in the pH range of 5.0-7.0, then eluted completely with 1.0 mL 0.5 mol x L(-1) HCl. The detection limits (3sigma) for analyte ions were 0.038 microg x L(-1) for Pb2+, 0.0005 microg x L(-1) for Cd2+ and 0.014 microg x L(-1) for Cu2+ with an enrichment factor of 50, and the relative standard deviations were 3.5% for Pb2+, 9.2% for Cd2+ and 4.7% for Cu2+ (c(Pb2+) = C(Cu2+) = 1.0 microg x L(-1); c(Cd2+) = 0.1 microg x L(-1), n=11). The proposed method was successfully applied to the determination of trace lead, cadmium and copper in environmental water samples (local tap water and lake water). In order to validate the method, the developed method was applied to the determination of lead, cadmium and copper in environmental water reference materials (ERMs, GSBZ 50009-88, PR China), and the results obtained were in good agreement with the certified values. PMID:19650505

Chen, Hao; Shen, Min; Xue, Ai-fang; Li, Sheng-qing; Pan, Si-yi

2009-05-01

199

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

200

Branchial cadmium and copper binding and intestinal cadmium uptake in wild yellow perch (Perca flavescens) from clean and metal-contaminated lakes.  

PubMed

Branchial binding kinetics and gastro-intestinal uptake of copper and cadmium where examined in yellow perch (Perca flavescens) from a metal-contaminated lake (Hannah Lake, Sudbury, Ontario, Canada) and an uncontaminated lake (James Lake, North Bay, Ontario, Canada). An in vivo approach was taken for gill binding comparisons while an in vitro gut binding assay was employed for gastro-intestinal tract (GIT) uptake analysis. By investigating metal uptake at the gill and the gut we cover the two main routes of metal entry into fish. Comparisons of water and sediment chemistries, metal burdens in benthic invertebrate, and metal burdens in the livers of perch from the two study lakes clearly show that yellow perch from Hannah L. are chronically exposed to a highly metal-contaminated environment compared to a reference lake. We found that metal-contaminated yellow perch showed no significant difference in gill Cd binding compared to reference fish, but they did show significant decreases in new Cd binding and absorption in their GITs. The results show that gill Cd binding may involve low-capacity, high-affinity binding sites, while gastro-intestinal Cd uptake involves binding sites that are high-capacity, low-affinity. From this we infer that Cd may be more critically controlled at the gut rather than gills. Significant differences in branchial Cu binding (increased binding) were observed in metal-contaminated yellow perch. We suggest that chronic waterborne exposure to Cu (and/or other metals) may be the dominant influence in gill Cu binding rather than chronic exposure to high Cu diets. We give supporting evidence that Cd is taken up in the GIT, at least in part, by a similar pathway as Ca(2+), principally that elevated dietary Ca(2+) reduces Cd binding and uptake. Overall our study reveals that metal pre-exposure via water and diet can alter uptake kinetics of Cu and Cd at the gill and/or the gut. PMID:17643503

Klinck, J S; Green, W W; Mirza, R S; Nadella, S R; Chowdhury, M J; Wood, C M; Pyle, G G

2007-08-30

201

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

202

Do We Take Minerals for Granted? Did you know that the average automobile contains more than a ton of iron  

E-print Network

about the lead, nickel, cadmium, or lithium used to make the batteries that store power for our cell a ton of iron and steel, 240 lbs of aluminum, 50 lbs of carbon, 42 lbs of copper, 41 lbs of silicon, 22? Do you know the cost of a pound of copper or an ounce of platinum? Though you are constantly reminded

203

Micronutrient status in female university students: iron, zinc, copper, selenium, vitamin B12 and folate.  

PubMed

Young women are at an increased risk of micronutrient deficiencies, particularly due to higher micronutrient requirements during childbearing years and multiple food group avoidances. The objective of this study was to investigate biomarkers of particular micronutrients in apparently healthy young women. Female students (n = 308; age range 18-35 year; Body Mass Index 21.5 ± 2.8 kg/m2; mean ± SD) were recruited to participate in a cross-sectional study. Blood samples were obtained from participants in the fasted state and analysed for biomarkers of iron status, vitamin B12, folate, homocysteine, selenium, zinc, and copper. The results show iron deficiency anaemia, unspecified anaemia, and hypoferritinemia in 3%, 7% and 33.9% of participants, respectively. Low vitamin B12 concentrations (<120 pmol/L) were found in 11.3% of participants, while 4.7% showed sub-clinical deficiency based on serum methylmalonic acid concentrations >0.34 ?mol/L. Folate concentrations below the reference range were observed in 1.7% (serum) or 1% (erythrocytes) of participants, and 99.7% of the participant had erythrocyte-folate concentrations >300 nmol/L. Serum zinc concentrations <10.7 ?mol/L were observed in 2% of participants. Serum copper and selenium concentrations were below the reference range in 23% and 11% of participants, respectively. Micronutrient deficiencies including iron and vitamin B12, and apparent excess of folate are present in educated Australian female students of childbearing age, including those studying nutrition. The effects of dietary behaviours and food choices on markers of micronutrient status require further investigation. PMID:25401503

Fayet-Moore, Flavia; Petocz, Peter; Samman, Samir

2014-01-01

204

Micronutrient Status in Female University Students: Iron, Zinc, Copper, Selenium, Vitamin B12 and Folate  

PubMed Central

Young women are at an increased risk of micronutrient deficiencies, particularly due to higher micronutrient requirements during childbearing years and multiple food group avoidances. The objective of this study was to investigate biomarkers of particular micronutrients in apparently healthy young women. Female students (n = 308; age range 18–35 year; Body Mass Index 21.5 ± 2.8 kg/m2; mean ± SD) were recruited to participate in a cross-sectional study. Blood samples were obtained from participants in the fasted state and analysed for biomarkers of iron status, vitamin B12, folate, homocysteine, selenium, zinc, and copper. The results show iron deficiency anaemia, unspecified anaemia, and hypoferritinemia in 3%, 7% and 33.9% of participants, respectively. Low vitamin B12 concentrations (<120 pmol/L) were found in 11.3% of participants, while 4.7% showed sub-clinical deficiency based on serum methylmalonic acid concentrations >0.34 ?mol/L. Folate concentrations below the reference range were observed in 1.7% (serum) or 1% (erythrocytes) of participants, and 99.7% of the participant had erythrocyte-folate concentrations >300 nmol/L. Serum zinc concentrations <10.7 ?mol/L were observed in 2% of participants. Serum copper and selenium concentrations were below the reference range in 23% and 11% of participants, respectively. Micronutrient deficiencies including iron and vitamin B12, and apparent excess of folate are present in educated Australian female students of childbearing age, including those studying nutrition. The effects of dietary behaviours and food choices on markers of micronutrient status require further investigation. PMID:25401503

Fayet-Moore, Flavia; Petocz, Peter; Samman, Samir

2014-01-01

205

Impairment of metabolic capacities in copper and cadmium contaminated wild yellow perch ( Perca flavescens)  

Microsoft Academic Search

This study examined variations in resting oxygen consumption rate (ROCR), post-exercise oxygen consumption rate, relative scope for activity (RSA), liver and muscle aerobic and anaerobic capacities (using citrate synthase (CS) and lactate dehydrogenase, respectively, as indicators), and tissue biosynthetic capacities (using nucleoside diphosphate kinase (NDPK) as an indicator), in wild yellow perch from four lakes varying in copper (Cu) and

Patrice Couture; Puja Rajender Kumar

2003-01-01

206

Haemolysis and Perturbations in the Systemic Iron Metabolism of Suckling, Copper-Deficient Mosaic Mutant Mice - An Animal Model of Menkes Disease  

PubMed Central

The biological interaction between copper and iron is best exemplified by the decreased activity of multicopper ferroxidases under conditions of copper deficiency that limits the availability of iron for erythropoiesis. However, little is known about how copper deficiency affects iron homeostasis through alteration of the activity of other copper-containing proteins, not directly connected with iron metabolism, such as superoxide dismutase 1 (SOD1). This antioxidant enzyme scavenges the superoxide anion, a reactive oxygen species contributing to the toxicity of iron via the Fenton reaction. Here, we analyzed changes in the systemic iron metabolism using an animal model of Menkes disease: copper-deficient mosaic mutant mice with dysfunction of the ATP7A copper transporter. We found that the erythrocytes of these mutants are copper-deficient, display decreased SOD1 activity/expression and have cell membrane abnormalities. In consequence, the mosaic mice show evidence of haemolysis accompanied by haptoglobin-dependent elimination of haemoglobin (Hb) from the circulation, as well as the induction of haem oxygenase 1 (HO1) in the liver and kidney. Moreover, the hepcidin-ferroportin regulatory axis is strongly affected in mosaic mice. These findings indicate that haemolysis is an additional pathogenic factor in a mouse model of Menkes diseases and provides evidence of a new indirect connection between copper deficiency and iron metabolism. PMID:25247420

Lenartowicz, Malgorzata; Starzynski, Rafal R.; Krzeptowski, Wojciech; Grzmil, Pawel; Bednarz, Aleksandra; Ogorek, Mateusz; Pierzchala, Olga; Staron, Robert; Gajowiak, Anna; Lipinski, Pawel

2014-01-01

207

An Experimental Study of Molten Salt Electrorefining of Uranium Using Solid Iron Cathode and Liquid Cadmium Cathode for Development of Pyrometallurgical Reprocessing  

Microsoft Academic Search

Electrorefining of uranium was studied for developing pyrometallurgical reprocessing technology of metal fuel cycle. After concentration dependence of polarization curve was measured, uranium was electrodeposited either on solid iron cathode or in liquid cadmium cathode. Design and operational conditions of the cathode were improved for obtaining much greater quantity of deposit, resulting in recovery of 732g of dendritic uranium on

Tadafumi KOYAMA; Masatoshi IIZUKA; Yuichi SHOJI; Reiko FUJITA; Hiroshi TANAKA; Tsuguyuki KOBAYASHI; Moriyasu TOKIWAI

1997-01-01

208

78 FR 65573 - Migratory Bird Hunting; Application for Approval of Copper-Clad Iron Shot and Fluoropolymer Shot...  

Federal Register 2010, 2011, 2012, 2013

...1018-AY61, 1018-AY66 Migratory Bird Hunting; Application for Approval of Copper-Clad...Shot Coatings as Nontoxic for Waterfowl Hunting AGENCY: Fish and Wildlife Service, Interior...iron shot and fluoropolymer coatings for hunting waterfowl and coots. We published a...

2013-11-01

209

77 FR 59158 - Migratory Bird Hunting; Application for Approval of Copper-Clad Iron Shot and Fluoropolymer Shot...  

Federal Register 2010, 2011, 2012, 2013

...1018-AY61, 1018-AY66 Migratory Bird Hunting; Application for Approval of Copper-Clad...Shot Coatings as Nontoxic for Waterfowl Hunting AGENCY: Fish and Wildlife Service, Interior...iron shot and fluoropolymer coatings for hunting waterfowl and coots. We published a...

2012-09-26

210

The effect of nonylphenylpolyethylene glycol on the kinetics and morphology of silver cemented using zinc, iron, copper and aluminum  

Microsoft Academic Search

The effect of nonylphenylpolyethylene glycol (D1) and cementing agents zinc, iron, copper and aluminum on silver cementation kinetics and deposit morphology was investigated. It was found that D1 inhibits both silver cementation and cementing agent dissolution with greater effect on cementing agent dissolution. The silver deposition rate and metal consumption per mole silver decreased in the order Zn, Fe, Cu,

M. Karavasteva

2009-01-01

211

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

212

Essential elements, cadmium, and lead in raw and pasteurized cow and goat milk  

Microsoft Academic Search

Fifteen essential elements plus cadmium and lead were determined in raw and pasteurized cow and goat milks by atomic absorption spectrophotometry. When results were compared on a wet weight basis, there were no significant differences between the raw and pasteurized milks except for cobalt, iron, and lead in goat milk. When copper in goat milk was expressed on a dry

Anthony Lopez; W. F. Collins; H. L. Williams

1985-01-01

213

Accumulation of cadmium, zinc, and copper in maternal blood and developmental placental tissue: differences between Finland, Estonia, and St. Petersburg.  

PubMed

Cadmium, zinc, and copper from placental tissue and blood samples at the first trimester (n = 64) and at term (n = 152) were analyzed; the welfare of newborns and placental 7-ethoxycoumarin O-deethylase (ECOD) activities in vitro were determined. The study material was collected from Finland, Estonia, and Russia. The results demonstrate that Cd starts to accumulate in the placenta during the first trimester and that Zn and Cu contents were significantly higher at the first trimester than at term. Among nonsmokers a negative correlation was found between placental Cu content and birth weight of neonates. Among smokers a positive correlation between placental Zn content and birth weight and ECOD activity was found. The birth weights correlated inversely with the length of time the mothers smoked. The highest Cd concentrations were detected in the samples collected from St. Petersburg. The data demonstrate an inverse accumulation of Zn and Cd throughout the pregnancy in the placenta and maternal blood samples. Zn may act as a positive marker or even an enzymatic enhancement for the human placental vital functions. Smoking, parity, age, and especially the place of residence affect the Cd, Zn, and Cu contents and ratios in placenta and mother's blood. PMID:10845782

Kantola, M; Purkunen, R; Kröger, P; Tooming, A; Juravskaja, J; Pasanen, M; Saarikoski, S; Vartiainen, T

2000-05-01

214

Vitamin E attenuates liver injury induced by exposure to lead, mercury, cadmium and copper in albino mice.  

PubMed

Water pollution is the contamination of water resources by harmful wastes or toxins. Both community and private sources of drinking water are susceptible to a myriad of chemical contaminants. Heavy metals pollution of surface water can create health risks. The present study was aimed to investigate the effect of vitamin E supplementation on male mice exposed to a mixture of some heavy metals (lead, mercury, cadmium and copper) in their drinking water for seven weeks. Significant increases of blood alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT) were detected in heavy metals-treated mice. Histopathologically, the liver sections from heavy metals-treated mice showed severe changes including disarrangement of hepatic strands, rupture in hepatocytes, advanced hepatocellular necrosis, dilation and congestion of blood vessels with hemorrhage, dense lymphocytic infiltration round the central vein and dark stained hepatocytic nuclei indicating cell pycnosis. Administration of vitamin E at a dose of 50 IU/kg body weight, five times weekly improved the observed biochemical and histopathological changes induced by these heavy metals intoxication. Hence, the results of this study suggest that vitamin E protects against these heavy metals-induced liver injury and the attenuating effect of vitamin E may be due to its antioxidant activity. PMID:23961152

Al-Attar, Atef M

2011-10-01

215

Sensitivity of mottled sculpins (Cottus bairdi) and rainbow trout (Onchorhynchus mykiss) to acute and chronic toxicity of cadmium, copper, and zinc  

USGS Publications Warehouse

Studies of fish communities of streams draining mining areas suggest that sculpins (Cottus spp.) may be more sensitive than salmonids to adverse effects of metals. We compared the toxicity of zinc, copper, and cadmium to mottled sculpin (C. bairdi) and rainbow trout (Onchorhynchus mykiss) in laboratory toxicity tests. Acute (96-h) and early life-stage chronic (21- or 28-d) toxicity tests were conducted with rainbow trout and with mottled sculpins from populations in Minnesota and Missouri, USA, in diluted well water (hardness = 100 mg/L as CaCO3). Acute and chronic toxicity of metals to newly hatched and swim-up stages of mottled sculpins differed between the two source populations. Differences between populations were greatest for copper, with chronic toxicity values (ChV = geometric mean of lowest-observed-effect concentration and no-observed-effect concentration) of 4.4 ??g/L for Missouri sculpins and 37 ??g/L for Minnesota sculpins. Cadmium toxicity followed a similar trend, but differences between sculpin populations were less marked, with ChVs of 1.1 ??g/L (Missouri) and 1.9 ??g/L (Minnesota). Conversely, zinc was more toxic to Minnesota sculpins (ChV = 75 ??g/L) than Missouri sculpins (chronic ChV = 219 ??g/L). Species-average acute and chronic toxicity values for mottled sculpins were similar to or lower than those for rainbow trout and indicated that mottled sculpins were among the most sensitive aquatic species to toxicity of all three metals. Our results indicate that current acute and chronic water quality criteria for cadmium, copper, and zinc adequately protect rainbow trout but may not adequately protect some populations of mottled sculpins. Proposed water quality criteria for copper based on the biotic ligand model would be protective of both sculpin populations tested. ?? 2007 SETAC.

Besser, J. M.; Mebane, C. A.; Mount, D. R.; Ivey, C. D.; Kunz, J. L.; Greer, I. E.; May, T. W.; Ingersoll, C. G.

2007-01-01

216

Analytical methods for copper, zinc and iron quantification in mammalian cells.  

PubMed

Highly complex analytical methods with different accuracies of measurement, reproducibilities and ease of analyses are currently being used to quantify metals in cellular media and tissue samples. In this review, the analytical methods commonly used for iron, copper and zinc quantification in mammalian cells are presented and discussed. Herein, we present a literature survey of the most commonly found concentrations of these metals in various mammalian cells in culture and tissues. The aim of this review is to help researchers in metallomic-related areas identify the method that best suits their needs for the accurate quantification of these metals in cells. This accuracy goes beyond simple knowledge of the limit of detection of each technique and needs to be evaluated through comparisons with similar previous studies. PMID:23925479

Cerchiaro, Giselle; Manieri, Tania Maria; Bertuchi, Fernanda Rodrigues

2013-10-01

217

Selective nucleation of iron phthalocyanine crystals on micro-structured copper iodide.  

PubMed

Morphological and structural control of organic semiconductors through structural templating is an efficient route by which to tune their physical properties. The preparation and characterisation of iron phthalocyanine (FePc)-copper iodide (CuI) bilayers at elevated substrate temperatures is presented. Thin CuI(111) layers are prepared which are composed of isolated islands rather than continuous films previously employed in device structures. Nucleation in the early stages of FePc growth is observed at the edges of islands rather than on the top (111) faces with the use of field emission scanning electron microscopy (FE-SEM). Structural measurements show two distinct polymorphs of FePc, with CuI islands edges nucleating high aspect ratio FePc crystallites with modified intermolecular spacing. By combining high substrate temperature growth and micro-structuring of the templating CuI(111) layer structural and morphological control of the organic film is demonstrated. PMID:25340949

Rochford, Luke A; Ramadan, Alexandra J; Heutz, Sandrine; Jones, Tim S

2014-12-14

218

Hot gas desulfurization with sorbents containing oxides of zinc, iron, vanadium and copper  

SciTech Connect

The main objective of this research is to evaluate the desulfurization performance of novel sorbents consisting of different combinations of zinc, iron, vanadium and copper oxides; and to develop a sorbent which can reduce H{sub 2}S levels to less than 1 ppmv, which can stabilize zinc, making operations above 650{degrees}C possible, and which can produce economically recoverable amounts of elemental sulfur during regeneration. This objective will be accomplished by evaluating the sorbent performance using fixed-bed and TGA experiments supported by sorbent characterization at various reaction extents. In the seventh quarter, the screening of the promoted sorbents in the packed bed reactor was continued. The results of this work were presented at the 1992 University Coal Research Contractors, Review Conference at Pittsburgh, PA.

Akyurtlu, A.; Akyurtlu, J.F.

1992-01-01

219

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

220

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.

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

2014-01-01

221

Size-dependent study of pulmonary responses to nano-sized iron and copper oxide nanoparticles.  

PubMed

The application of nanotechnology in various fields has resulted in a tremendous increase in the synthesis of variety of engineered nanoparticles (NPs). These applications are possible only due to the small size and large surface area of the NPs which imparts them unique properties. Inorganic oxide NPs as iron and copper oxide NPs are widely used in several biomedical and synthetic applications. The beneficial aspects of these NPs are concurrently associated with several drastic and deleterious effects as well. Size of the NPs plays a critical role in systemic clearance from the body. Initial studies have confirmed inflammatory responses in mice associated with non-biodegradable oxide NPs. The associated oxidative stress varied from mild effects to reactive oxygen species generation which can potentiate DNA damage or even induced carcinogenesis. Copper oxide NPs, in particular, induced acute toxicity and inflict neutrophil infiltration. This chapter focuses on the applicability of various in vivo techniques for studying the effect of these NPs, especially on the pulmonary system. These in vivo techniques would certainly provide a better understanding and insight into the mechanistic pathways by which these NPs interact with various organ systems in human body. PMID:23740125

Kumar, Rajiv; Nagesha, Dattatri K

2013-01-01

222

Influence of iron overload on manganese, zinc, and copper concentration in rat tissues in vivo: study of liver, spleen, and brain.  

PubMed

Although hemochromatosis and pathological situations due to chronic iron overload have been extensively described, there is little information about the influence of iron on other trace elements in the cell. The aim of this study was to investigate changes in the concentration of zinc, manganese, and copper in the liver, spleen, and brain of rats after iron overload. Iron overload in Wistar rats was achieved by iron-supplemented diet or by intraperitoneal or intravenous injection of polymaltose iron. Iron, zinc, manganese, and copper were determined by atomic absorption spectrophotometry. Iron overload in rats, regardless of the route of its application, resulted in an increase not only of iron but also of zinc and manganese in the liver and the spleen, whereas the content of these metals in the brain did not change. The copper content of the liver, spleen, and brain remained the same after iron overload. The increase of zinc and manganese in the liver and spleen following iron overload was probably a result not only of increased intestinal absorption but also of increased uptake from the cell. This is also supported by the fact that no increase in the zinc and manganese concentrations occurred in the brain since, despite iron overload, the iron content remained constant. PMID:9801930

Vayenas, D V; Repanti, M; Vassilopoulos, A; Papanastasiou, D A

1998-01-01

223

The Menkes/Wilson disease gene homologue in yeast provides copper to a ceruloplasmin-like oxidase required for iron uptake.  

PubMed Central

The CCC2 gene of the yeast Saccharomyces cerevisiae is homologous to the human genes defective in Wilson disease and Menkes disease. A biochemical hallmark of these diseases is a deficiency of copper in ceruloplasmin and other copper proteins found in extracytosolic compartments. Here we demonstrate that disruption of the yeast CCC2 gene results in defects in respiration and iron uptake. These defects could be reversed by supplementing cells with copper, suggesting that CCC2 mutant cells were copper deficient. However, cytosolic copper levels and copper uptake were normal. Instead, CCC2 mutant cells lacked a copper-dependent oxidase activity associated with the extracytosolic domain of the FET3-encoded protein, a ceruloplasmin homologue previously shown to be necessary for high-affinity iron uptake in yeast. Copper restored oxidase activity both in vitro and in vivo, paralleling the ability of copper to restore respiration and iron uptake. These results suggest that the CCC2-encoded protein is required for the export of copper from the cytosol into an extracytosolic compartment, supporting the proposal that intracellular copper transport is impaired in Wilson disease and Menkes disease. Images Fig. 1 Fig. 3 PMID:7708696

Yuan, D S; Stearman, R; Dancis, A; Dunn, T; Beeler, T; Klausner, R D

1995-01-01

224

Copper(i)- and copper(0)-promoted homocoupling and homocoupling-hydrodehalogenation reactions of dihalogenoclathrochelate precursors for C-C conjugated iron(ii) bis-cage complexes.  

PubMed

Iron(ii) dibromo- and diiodoclathrochelates undergo copper(i)-promoted reductive homocoupling in HMPA at 70-80 °C leading to C-C conjugated dibromo- and diiodo-bis-clathrochelates in high yields. Under the same conditions, their dichloroclathrochelate analog does not undergo the same homocoupling reaction, so the target dichloro-bis-cage product was obtained in high yield via dimerization of its heterodihalogenide iodochloromonomacrobicyclic precursor. The use of NMP as a solvent at 120-140 °C gave the mixture of bis-clathrochelates resulting from a tandem homocoupling-hydrodehalogenation reaction: the initial acetonitrile copper(i) solvato-complex at a high temperature underwent re-solvatation and disproportionation leading to Cu(ii) ions and nano-copper, which promoted the hydrodehalogenation process even at room temperature. The most probable pathway of this reaction in situ includes hydrodehalogenation of the already formed dihalogeno-bis-clathrochelate via the formation of reduced anion radical intermediates. As a result, chemical transformations of the iron(ii) dihalogenoclathrochelates in the presence of an acetonitrile copper(i) solvato-complex were found to depend both on the nature of halogen atoms in their ribbed chelate fragments and on reaction conditions (i.e. solvent and temperature). The C-C conjugated iron(ii) dihalogeno-bis-clathrochelates easily undergo nucleophilic substitution with various N,S-nucleophiles giving ribbed-functionalized bis-cage species. These iron(ii) complexes were characterized by elemental analysis, MALDI-TOF mass spectrometry, IR, UV-Vis, (1)H and (13)C NMR spectroscopy, and by X-ray diffraction; their electrochemical properties were studied by cyclic voltammetry. The isomeric shift values in (57)Fe Mössbauer spectra of such cage compounds allowed identifying them as low-spin iron(ii) complexes, while those of the quadrupole splitting are the evidence for a significant TP distortion of their FeN6-coordination polyhedra. As follows from CV data, the C-C conjugated iron(ii) bis-clathrochelates undergo stepwise electrochemical reduction and oxidation giving mixed-valence Fe(II)Fe(I) and Fe(II)Fe(III) bis-cage intermediates. PMID:25056255

Varzatskii, Oleg A; Shul'ga, Sergey V; Belov, Alexander S; Novikov, Valentin V; Dolganov, Alexander V; Vologzhanina, Anna V; Voloshin, Yan Z

2014-11-18

225

Derivative potentiometric stripping analysis (dPSA) used for the determination of cadmium, copper, lead, and zinc in Sicilian olive oils.  

PubMed

Derivative potentiometric stripping analysis (dPSA) was utilized to evaluate the Cd(II), Cu(II), Pb(II), and Zn(II) content in olive oil samples produced in Sicily in the crop year 2000-2001. The repeatability of the method was attested at 86.36% for cadmium, at 94.94% for copper, at 99.00% for lead, and at 98.92% for zinc. Recovery tests were carried out, both on cleanup procedures and on extraction steps, on olive oil spiked at different levels; obtained recoveries were 84.52 +/- 9.86 for cadmium, 97.34 +/- 2.72 for copper, 100.68 +/- 0.67 for lead and 83.35 +/- 1.72 for zinc. Theoretic detection limits were 1.2 ng g(-1) for Cd, 3.6 ng g(-1) for Cu, 5.9 ng g(-1) for Pb, and 14.3 ng g(-1) for Zn. Found concentrations range were 15.94-58.51 ng g(-1) for Cu, 32.64-156.48 ng g(-1) for Pb, and 157.00-385.22 ng g(-1) for Zn. Copper, lead, and zinc were found in all samples. The main advantage of this determination consists of a not too aggressive metals extraction procedure using hydrochloric acid, which avoids losses of elements typical of sample calcinations methods. PMID:12009967

La Pera, Lara; Lo Curto, Simona; Visco, Alessandro; La Torre, Loredana; Dugo, Giacomo

2002-05-22

226

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

227

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

USGS Publications Warehouse

The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47?µg Cd/L to 2.62?µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46?µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02?µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51?µg Cu/L to 21.9?µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model–normalized EC50 of 209?µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution.

Calfee, Robin D.; Little, Edward E.; Puglis, Holly J.; Scott, Erinn L.; Brumbaugh, William G.; Mebane, Christopher A.

2014-01-01

228

Influence of iron overload on manganese, zinc, and copper concentration in rat tissues in vivo: study of liver, spleen, and brain  

Microsoft Academic Search

Although hemochromatosis and pathological situations due to chronic iron overload have been extensively described, there is\\u000a little information about the influence of iron on other trace elements in the cell. The aim of this study was to investigate\\u000a changes in the concentration of zinc, manganese, and copper in the liver, spleen, and brain of rats after iron overload. Iron\\u000a overload

D. V. Vayenas; M. Repanti; A. Vassilopoulos; D. A. Papanastasiou

1998-01-01

229

Study of Reaction Mechanisms for Copper-Cobalt-Iron Sulfide Concentrates in the Presence of Lime and Carbon  

NASA Astrophysics Data System (ADS)

The reaction mechanisms for the carbothermic reduction of complex mineral sulfide concentrates in the presence of lime were studied between 1073 K and 1323 K. The reaction mechanisms were studied by stopping the reduction experiments at different times and analyzing the reaction products by x-ray diffraction and scanning electron microscopy techniques. Magnetite (Fe3O4) and digenite (Cu1.8S) were the initial phases formed during reduction of CuFeS2 and Cu5FeS4 mineral particles, such that metallization of iron occurred before copper above 1173 K and at an equal stoichiometric ratio of CaO and C. The metallization of iron was found to take place via reduction of intermediate oxide phase (Fe3O4/FeO), whereas metallization of copper occurred via diffusion of S2- ions away from the mineral particles or via formation of Cu-O-S liquid phase. Metallic iron and cobalt were embedded in the copper matrix due to a preferential reduction of iron and cobalt from the Cu-Fe-S and Cu-Co-S type of mineral particles. The effects of CaO/C ratio were analyzed and the rate of reactions was increasing with an increase in the CaO/C ratio. The formation of liquid phase has been discussed. The experimental results were found to be in good agreement with the thermodynamic predictions.

Hara, Yotamu Stephen Rainford

2013-11-01

230

Reactivity of nanoparticles; interaction between zinc and copper oxide nanoparticles and iron ions in an alkaline medium  

Microsoft Academic Search

The reactivity of zinc and copper oxide nanoparticles was investigated upon their interaction with iron oxides. It was ascertained\\u000a that, depending on the reaction conditions, nanoparticles of zinc and copper ferrites (ZnFe2O4 and CuFe2O4) or core\\/shell nanoparticles (Fe3O4\\/ZnO) are produced. Size, composition, and structure of the resulting nanoparticles were determined by transmission electron\\u000a microscopy and X-ray diffraction analysis. The average

A. Ya. Shalyapina; L. A. Polyakova; M. A. Zaporozhets; E. M. Khokhlov; S. P. Gubin

2011-01-01

231

Accumulation and soluble binding of cadmium, copper, and zinc in the polychaete Hediste diversicolor from coastal sites with different trace metal bioavailabilities.  

PubMed

Bioaccumulation of cadmium, copper, and zinc was examined in common ragworms Hediste diversicolor from control (Bay of Somme, Blackwater) and metal-rich (Seine estuary, Boulogne harbor, Restronguet Creek) sites in France and the United Kingdom. The degree of exposure in the field was assessed by considering both total concentrations in superficial sediment and the quantities of metals which may be released in vitro at different pH levels. Among the three contaminated sites, release of the three metals was not detectable in Boulogne harbor, in correlation with limited enhancement of the metal concentrations in the common ragworms from this site. Even at those sites where zinc could be released in vitro from the sediment, zinc concentrations were not enhanced in common ragworms, in agreement with previous findings indicating that the body content of this metal is regulated in H. diversicolor. At all the studied sites, bioaccumulated zinc was mainly in cytosolic form. The distribution of cadmium and copper varied according to the origin of the common rag-worms, the insoluble fraction increasing with the degree of contamination (cadmium in the Restronguet Creek, copper in the Seine estuary, and even more in Restronguet Creek). In the cytosolic fraction, metals were partly linked to cytosolic heat-stable thiolic compounds (CHSTC) with molecular masses (5-6 kDa and about 12 kDa) consistent with metallothionein-like proteins (MTLP). Metal-binding to MTLP varied with the degree of contamination and with the metal studied. In contrast to many invertebrates, the presence of metal-binding CHSTC (MM about 2 kDa) other than MTLP seems to be a peculiar feature of H. diversicolor. PMID:14708663

Berthet, B; Mouneyrac, C; Amiard, J C; Amiard-Triquet, C; Berthelot, Y; Le Hen, A; Mastain, O; Rainbow, P S; Smith, B D

2003-11-01

232

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

233

Variations between rice cultivars in iron and manganese plaque on roots and the relation with plant cadmium uptake.  

PubMed

To understand certain mechanisms causing variations between rice cultivars with regard to cadmium uptake and tolerance, pot soil experiments were conducted with two rice cultivars of different genotypes under different soil Cd levels. The relationships between plant Cd uptake and iron/manganese (Fe/Mn) plaque formation on roots were investigated. The results showed that rice cultivars differed markedly in Cd uptake and tolerance. Under soil Cd treatments, Cd concentrations and accumulations in the cultivar Shanyou 63 (the genotype indica) were significantly higher than those in the cultivar Wuyunjing 7 (the genotype japonica) (P < 0.01, or P < 0.05), and Shanyou 63 was more sensitive to Cd toxicity than Wuyunjing 7. The differences between the rice cultivars were the largest at relatively low soil Cd level (i.e., 10 mg/kg). Fe concentrations in dithionite-citrate-bicarbonate root extracts of Shanyou 63 were generally lower than that of Wuyunjing 7, and the difference was the most significant under the treatment of 10 mg Cd/kg soil. The results indicated that the formation of iron plaque on rice roots could act as a barrier to soil Cd toxicity, and may be a "buffer" or a "reservoir" which could reduce Cd uptake into rice roots. And the plaque may contribute, to some extent, to the genotypic differences of rice cultivars in Cd uptake and tolerance. PMID:21174997

Liu, Jianguo; Cao, Changxun; Wong, Minghung; Zhang, Zhijun; Chai, Yuhong

2010-01-01

234

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

235

Determination of copper, nickel, cobalt, silver, lead, cadmium, and mercury ions in water by solid-phase extraction and the RP-HPLC with UV-Vis detection  

Microsoft Academic Search

A new method for the simultaneous determination of seven heavy metal ions in water by solid-phase extraction and reversed-phase high-performance liquid chromatography (RP-HPLC) was developed. The copper, nickel, cobalt, silver, lead, cadmium, and mercury ions were pre-column derivatized with tetra(m-aminophenyl)porphyrin (Tm-APP) to form colored chelates. The metal-Tm-APP chelates in 100 mL of sample were preconcentrated to 1 mL by solid-phase

Qiufen Hu; Guangyu Yang; Yiyun Zhao; Jiayuan Yin

2003-01-01

236

Evaluating the Metal Source(s) of Iron Oxide-Copper-Gold (IOCG) Deposits (Invited)  

NASA Astrophysics Data System (ADS)

Iron oxide - copper - gold deposits (IOCG) are characterized by high modal abundances of magnetite and/or hematite, ubiquitous and variable grades of Cu and Au, and, often, economic grades of other metals including REE, U, Ag, Mo and Zn. The largest deposits contain >1 billion tonnes of iron. There seems to be a general consensus that metals in IOCG deposits were transported by, and precipitated from, aqueous fluids. However, there is a lack of agreement for the source of the metal-bearing aqueous fluid(s) as well as the source of iron and other metals (i.e., magmatic or hydrothermal, or some combination of the two). Published fluid inclusion data indicate that metal-bearing aqueous fluids were trapped over a wide range of temperatures, with homogenization temperatures between 500 and 600 °C for inclusions associated with the precipitation of iron-oxide minerals, and between 300 and 500 °C for inclusions associated with main-stage sulfides (e.g., chalcopyrite, pyrite). The high trapping temperatures for fluid inclusions and the observation that some IOCG deposits appear to be related temporally and spatially to igneous intrusions, characteristics similar to those observed for porphyry-type ore deposits, have led some authors to propose that magmatic-hydrothermal aqueous fluids are responsible for IOCG formation. Others, however, favor a genetic model that invokes large-scale circulation of basinal brines, which are heated by magmatic intrusions and subsequently leach Fe and other metals from the crust. Evidence cited for this model includes the pervasive alkali metasomatism associated with some IOCG deposits, and the depletion of Fe, Cu and Au in some deposit wall rocks. Stable isotope evidence thus far is inconclusive. Published d34S values for IOCG deposits range from -30 to +30, but generally cluster around zero per mil. d18O ranges from ~0 to +10 per mil. Chlorine isotope values for fluids in inclusions liberated from quartz, calcite and apatite are consistent with mantle derived Cl, mixed with basinal brines. All of these data provide important constraints on various aspects of IOCG deposits. None of these data however provide direct evidence for the source of the metals in IOCG deposits. In this contribution, we will evaluate the source of Fe in selected IOCG deposits, as well as the plausibility for other metals to be magmatically sourced. Our approach combines: 1) solubility data for iron in aqueous fluid at temperatures that span the hydrothermal to magmatic regime; 2) new experimental data that constrain the fractionation of iron isotopes among silicate melt, aqueous fluid, magnetite, and sulfide, and at sub-solidus temperatures between aqueous fluid and magnetite; and 3) new iron isotope data for several IOCG deposits of the Coastal Cordillera in northern Chile. The combination of these data allows us to discriminate between the proposed basinal brine and magmatic-hydrothermal models.

Simon, A. C.; Bilenker, L.; Lundstrom, C.; Reich, M.; Barra, F.; Hanchar, J. M.; Westhues, A.

2013-12-01

237

Milk trace elements in lactating cows environmentally exposed to higher level of lead and cadmium around different industrial units  

Microsoft Academic Search

The present investigation was carried out to assess the trace mineral profile of milk from lactating cows reared around different industrial units and to examine the effect of blood and milk concentration of lead and cadmium on copper, cobalt, zinc and iron levels in milk. Respective blood and milk samples were collected from a total of 201 apparently healthy lactating

R. C. Patra; D. Swarup; P. Kumar; D. Nandi; R. Naresh; S. L. Ali

2008-01-01

238

Mineral chemistry of ore and hydrothermal alteration at the Sossego iron oxide–copper–gold deposit, Carajás Mineral Province, Brazil  

Microsoft Academic Search

The Sossego iron oxide–copper–gold deposit in the Carajás Mineral Province comprises two major orebodies, Sequeirinho and Sossego. Sodic alteration (albite–hematite) and sodic–calcic alteration zones represented by albite, ferro-edenite\\/hastingsite (up to 3.8 wt.% Cl), actinolite\\/magnesiohornblende, magnetite, titanite, epidote, and calcite are predominant at Sequeirinho. Magnetite bodies with envelopes of apatite-rich actinolitite were formed with the sodic–calcic event at high temperatures (~500 °C at

Lena Virgínia Soares Monteiro; Roberto Perez Xavier; Murray W. Hitzman; Caetano Juliani; Carlos Roberto de Souza Filho; Emerson de R. Carvalho

2008-01-01

239

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

240

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

241

Phase diagram, thermal stability, and high temperature oxidation of the ternary copper-nickel-iron system  

NASA Astrophysics Data System (ADS)

Due to the aluminum industry demands, a large effort has recently been devoted to the development of special alloys to be used as inert anodes for a newly designed aluminum reduction cell. The implementation of this new technology aims at the replacement of the graphite anodes that have been used for over 100 years in aluminum smelting, which would reduce fossil carbon consumption, and eliminate the emission of carbon dioxide and of perfluorocarbons. Ternary alloys containing copper, nickel, and iron have been the subject of the research activities. The present research focused on the stability of the Cu-Ni-Fe alloys at high temperatures in oxidizing and fluoridating environments. The experimental methods included thermodynamic calculations of the phase diagram (Thermocalc), optical microscopy and microprobe microstructural and chemical investigations (EMPA), small-angle neutron scattering (SANS), differential thermal analysis (DTA), and air-oxidation studies. The results have led to the optimization of the Cu-Ni-Fe ternary phase diagram and to an extensive study of the thermodynamics and kinetics of the spinodal decomposition and discontinuous reactions occurring during ageing as a function of alloy composition. The oxidizing reactions occurring in air at high temperatures at the surface of the alloys have been also discussed in terms of thermodynamic and kinetic laws. The phase formation in a fluorine containing environment as encountered in an aluminum electrolytic cell is predicted using principles of physical chemistry.

Gallino, Isabella

242

Assessing Plasma Levels of Selenium, Copper, Iron and Zinc in Patients of Parkinson's Disease  

PubMed Central

Trace elements have been recognized to play an important role in the development of Parkinson’s disease (PD). However, it is difficult to precisely identify the relationship between these elements and the progression of PD because of an insufficient number of patients. In this study, quantifications of selenium (Se), copper (Cu), iron (Fe) and zinc (Zn) by atomic absorption spectrophotometry were performed in plasma from 238 PD patients and 302 controls recruited from eastern China, which is so far the largest cohort of PD patients and controls for measuring plasma levels of these elements. We found that plasma Se and Fe concentrations were significantly increased whereas Cu and Zn concentrations decreased in PD patients as compared with controls. Meanwhile, these four elements displayed differential changes with regard to age. Linear and logistic regression analyses revealed that both Fe and Zn were negatively correlated with age in PD patients. Association analysis suggests that lower plasma Se and Fe levels may reduce the risk for PD, whereas lower plasma Zn is probably a PD risk factor. Finally, a model was generated to predict PD patients based on the plasma concentrations of these four trace elements as well as other features such as sex and age, which achieved an accuracy of 80.97±1.34% using 10-fold cross-validation. In summary, our data provide new insights into the roles of Se, Cu, Fe and Zn in PD progression. PMID:24340079

Cheng, Xing; Wang, Jian-Yong; Hu, Bei-Lei; Zhang, Yan; Zhang, Xiong; Zhu, Jian-Hong

2013-01-01

243

Transcription patterns of genes encoding four metallothionein homologs in Daphnia pulex exposed to copper and cadmium are time- and homolog- dependent  

PubMed Central

Metallothioneins are proteins that play an essential role in metal homeostasis and detoxification in nearly all organisms studied to date. Yet discrepancies between outcomes of chronic and acute exposure experiments hamper the understanding of the regulatory mechanisms of their isoforms following metal exposure. Here, we investigated transcriptional differences among four identified homologs (mt1–mt4) in Daphnia pulex exposed across time to copper and cadmium relative to a control. Transcriptional upregulation of mt1 and mt3 was detected on day four following exposure to cadmium, whereas that of mt2 and mt4 was detected on day two and day eight following exposure to copper. These results confirm temporal and metal-specific differences in the transcriptional induction of genes encoding metallothionein homologs upon metal exposure which should be considered in ecotoxicological monitoring programs of metal-contaminated water bodies. Indeed, the mRNA expression patterns observed here illustrate the complex regulatory system associated with metallothioneins, as these patterns are not only dependent on the metal, but also on exposure time and the homolog studied. Further phylogenetic analysis and analysis of regulatory elements in upstream promoter regions revealed a high degree of similarity between metallothionein genes of Daphnia pulex and Daphnia magna, a species belonging to the same genus. These findings, combined with a limited amount of available expression data for D. magna metallothionein genes, tentatively suggest a potential generalization of the metallothionein response system between these Daphnia species. PMID:24113165

Asselman, Jana; Shaw, Joseph R.; Glaholt, Stephen P.; Colbourne, John K.; De Schamphelaere, Karel AC.

2013-01-01

244

Expression of metallothionein of freshwater crab (Sinopotamon henanense) in Escherichia coli enhances tolerance and accumulation of zinc, copper and cadmium.  

PubMed

Metallothioneins (MTs) are ubiquitous metal-binding, cysteine-rich, small proteins and play a major role in metal homeostasis and/or detoxification in all organisms. In a previous study, a novel full length MT gene was isolated from the freshwater crab (Sinopotamon henanense), a species widely distributed in Shanxi and Henan Provinces, China. In this report, the gene for the crab MT was inserted into a PET-28a-6His-SUMO vector and recombinant soluble MT was over-expressed as fusions with SUMO in Escherichia coli. The recombinant fusion protein was purified by affinity chromatography and its biochemical properties were analyzed. In addition, on the basis of constructing SUMO-MT, two mutants, namely SUMO-MTt1 and SUMO-MTt2, were constructed to change the primary structure of SUMO-MT using site-directed mutagenesis techniques with the amino acid substitutions D3C and S37C in order to increase metal-binding capacity of MT. E. coli cells expressing SUMO-MT and these single-mutant proteins exhibited enhanced metal tolerance and higher accumulation of metal ions than control cells. The results showed that the bioaccumulation and tolerance of Zn(2+), Cu(2+) and Cd(2+) in these strains followed the decreasing order of SUMO-MTt1 > SUMO-MTt2 > SUMO-MT. E. coli cells have low tolerance and high accumulation towards cadmium compared to zinc and copper. These results show that the MT of S. henanense could enhance tolerance and accumulation of metal ions. Moreover, we were able to create a novel protein based on the crab MT to bind metal ions at high density and with high affinity. Therefore, SUMO-MT and its mutants can provide potential candidates for heavy metal bioremediation. This study could help further elucidate the mechanism of how the crab detoxifies heavy metals and provide a scientific basis for environment bioremediation of heavy metal pollution using the over-expression of the crab MT and mutant proteins. PMID:24276409

He, Yongji; Ma, Wenli; Li, Yingjun; Liu, Jinping; Jing, Weixin; Wang, Lan

2014-01-01

245

Concentrations of Arsenic, Cadmium, Copper, Lead, Selenium, and zinc in fish from the Mississippi River basin, 1995.  

PubMed

Fish were collected in late 1995 from 34 National Contaminant Biomonitoring Program (NCBP) stations and 12 National Water Quality Assessment Program (NAWQA) stations in the Mississippi River basin (MRB), and in late 1996 from a reference site in West Virginia. The NCBP sites represented key points (dams, tributaries, etc.) in the largest rivers of the MRB. The NAWQA sites were typically on smaller rivers and were selected to represent dominant land uses in their watersheds. The West Virginia site, which is in an Eastern U.S. watershed adjacent to the MRB, was selected to document elemental concentrations in fish used for other aspects of a larger study and to provide additional contemporaneous data on background elemental concentrations. At each site four samples, each comprising (nominally) 10 adult common carp (Cyprinus carpio, 'carp') or black bass (Micropterus spp., 'bass') of the same sex, were collected. The whole fish were composited by station, species, and gender for analysis of arsenic (As), lead (Pb), and selenium (Se) by atomic absorption spectroscopy and for cadmium (Cd), copper (Cu), and zinc (Zn) by inductively-coupled plasma emission spectroscopy. Concentrations of most of the elements examined were lower in both carp and bass from the reference site, a small impoundment located in a rural area, than from the NCBP and NAWQA sites on rivers and larger impoundments. In contrast, there were few overall differences between NCBP sites NAWQA sites. The 1995 results generally confirmed the continued weathering and re-distribution of these elemental contaminants in the MRB; concentrations declined or were unchanged from 1984-1986 to 1995 at most NCBP sites, thus continuing two-decade trends. Exceptions were Se at Station 77 (Arkansas R. at John Martin Reservoir, CO), where concentrations have been elevated historically and increased slightly (to 3.8-4.7 microg g-(1) in bass and carp); and Pb, Cd, and Zn at Station 67 (Allegheny R. at Natrona, PA), where levels of these metals were high in the past and increased from 1986 to 1995. PMID:15887377

Schmitt, Christopher J

2004-01-01

246

High performance liquid chromatographic separation and UV determination of cobalt, copper iron and platinum in pharmaceutical preparations using bis(isovalerylacetone)ethylenediimine as complexing reagent  

Microsoft Academic Search

The reagent bis(isovalerylacetone)ethylenediimine(H2IVA2en) has been examined for HPLC separation and UV determination of cobalt, copper, iron and platinum using off-line precolumn derivatization and extraction in chloroform. The complexes of cobalt(II), cobalt(III), iron(II), iron(III) and the reagent have been subsequently separated on a Microsorb C-18 column. The complexes were eluted isocratically using ternary mixtures of methanol\\/water\\/acetonitrile. Detection was achieved by UV

Muhammad Yas Khuhawar; Shah Nawaz Lanjwani

1998-01-01

247

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

248

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. PMID:23629701

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

2013-01-01

249

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

PubMed

The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47?µg Cd/L to 2.62?µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46?µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02?µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51?µg Cu/L to 21.9?µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model-normalized EC50 of 209?µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution. Environ Toxicol Chem 2014;33:2259-2272. © 2014. The Authors. This article is a US government work and, as such, is in the public domain in the United States of America. Environmental Toxicology and Chemistry published byWiley Periodicals, Inc. on behalf of SETAC. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. PMID:25043712

Calfee, Robin D; Little, Edward E; Puglis, Holly J; Scott, Erinn; Brumbaugh, William G; Mebane, Christopher A

2014-10-01

250

Factors Influencing the DNA Nuclease Activity of Iron, Cobalt, Nickel, and Copper Chelates  

PubMed Central

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 coreactants were quantified by gel electrophoresis, yielding second-order rate constants for DNAsupercoiled to DNAnicked conversion up to 2.5 ×106 M-1min-1, and for DNAnicked to DNAlinear up to 7 ×105 M-1min-1. Relative rates of radical generation and characterization of radical species were determined by reaction with the fluorescent radical probe TEMPO-9-AC and rhodamine B. Ascorbate turnover rate constants ranging from 9.1×10-3 to 8.2 min-1 were determined, although many complexes demonstrated no measureable activity. Inhibition and Freifelder-Trumbo analysis of DNA cleavage supported concerted cleavage of dsDNA by a metal associated ROS in the case of Cu2+(aq), Cu-KGHK, Co-KGHK, and Cu-NTA and stepwise cleavage for Fe2+(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 mV to +1111 mV versus NHE, and complexes demonstrated optimal catalytic activity in the range of the physiological redox coreactants ascorbate and peroxide (-66 to +380 mV). PMID:21815680

Joyner, Jeff C.; Reichfield, Jared; Cowan, J. A.

2012-01-01

251

Copper  

MedlinePLUS

... copper status and certain CVD risk markers in young healthy women. Br J Nutr. 2005;94:231-236. Cassileth B. The Alternative Medicine Handbook: The Complete Reference Guide to Alternative and Complementary Therapies. New York, NY: W.W. Norton; 1998. Castillo-Durán C, Fisberg M, ...

252

Biochemical lesions in copper-deficient rats caused by secondary iron deficiency. Derangement of protein synthesis and impairment of energy metabolism  

PubMed Central

Severe copper deficiency was induced in rats by rearing nursing dams and their offsprings on a semisynthetic diet comprising all the requisite nutrients and trace metals except copper. The copper-deprived rats exhibited growth retardation, severe anaemia, loss of caeruloplasmin, decrease of cytochrome oxidase, accumulation of salt-soluble collagen and a drastic decrease in iron in plasma and liver. Apart from these characteristic signs of deficiency, a marked inhibition of protein synthesis was found to occur both in vivo and in cell-free liver preparations. The curtailed ability to carry out endogenously coded amino acid incorporation into protein contrasted with the unimpaired poly(U)-acid-directed phenylalanine polymerization. This inhibition pattern, as well as the attendant disaggregation of the liver polyribosomes, suggested that the primary biosynthetic lesion was located at the stage of peptide-chain initiation. Concurrently with this alteration there was a pronounced depletion of the hepatic ATP content, associated with a parallel depression of mitochondrial respiration and an enhancement of ATPase activity. Supplementation of the copper-deficient diet with a 2–4-fold excess of iron (relative to the standard diet) prevented growth retardation and anaemia and restored normal energy metabolism, as well as unimpaired protein-synthesizing capacity. The conclusion that these disturbances were primarily determined by the secondary iron deficiency was also borne out by the finding that similar alterations occurred in rats maintained on a copper-sufficient but iron-deficient diet. On the other hand, the iron-fortified diet failed to reverse the other signs of copper deficiency, namely the loss of caeruloplasmin, the diminished rate of cytochrome oxidase and the increase of soluble collagen. The interrelations between the various biochemical lesions induced by deprivation of copper or iron are discussed and the possible role of ATP depletion in determining the derangement of protein synthesis is considered. PMID:6258558

Weisenberg, Emil; Halbreich, Avraham; Mager, Jacob

1980-01-01

253

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

254

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

255

Trophic relationships and transference of cadmium, copper, lead and zinc in a subtropical coastal lagoon food web from SE Gulf of California.  

PubMed

Trophic relationships and heavy metal transference in a coastal subtropical lagoon marine food web were investigated through the use of stable isotopes in food sources and biota. A selective extraction scheme was applied to the surface sediments as an indirect way to evaluate the potential of toxicity of metals. Results showed that cadmium, copper, lead and zinc concentrations were within sediment quality guidelines criteria. Concentrations of these metals in organisms varied widely among functional groups and within the same and closely related taxa. delta(13)C values varied significantly among organisms from different functional groups, while the delta(15)N values varied according with their feeding habits. Cd, Cu, Pb, and Zn were not positively transferred (biomagnification factor <1) through entire food web. However, a partial positive transference was observed for Cu and Zn involving three trophic levels (from the phytoplankton to crab as secondary consumer). PMID:19818990

Jara-Marini, M E; Soto-Jiménez, M F; Páez-Osuna, F

2009-11-01

256

Effects of sulfur, zinc, iron, copper, manganese, and boron applications on sunflower yield and plant nutrient concentration  

SciTech Connect

Sulfur, zinc, iron, copper, manganese, and boron application did not affect the seed yield or oil percentage of sunflower (Helianthus annuus L.) on both dryland and irrigated soils in North Dakota in 1981. Field averages indicated significant Zn, Mn, and B uptake by sunflower at the 12-leaf stage as a result of fertilization with these elements. Increased Zn uptake was also observed in the uppermost mature leaf at anthesis from zinc fertilization. Although sunflower yield from boron fertilization was not significantly different from the check, a trend was observed in which boron fertilization seemed to decrease sunflower yield. Sunflower yields from the boron treatment were the lowest out of seven treatments in three out of four fields. Also, sunflower yield from the boron treatment was significantly lower than both iron and sulfur treatments when all fields were combined.

Hilton, B.R.; Zubriski, J.C.

1985-01-01

257

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

258

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. PMID:24901737

Tang, Yulin; Cao, Yan; Qiu, Jianbin; Gao, Zhan; Ou, Zhonghua; Wang, Yajing; Zheng, Yizhi

2014-01-01

259

Myriophyllum alterniflorum DC., biomonitor of metal pollution and water quality. Sorption/accumulation capacities and photosynthetic pigments composition changes after copper and cadmium exposure.  

PubMed

Watermilfoil genus Myriophyllum could be used in ecological surveys as in-situ biomonitors of metal pollution and water quality due to its ability to accumulate chemicals. The copper and cadmium sorption characteristics of Myriophyllum alterniflorum have been investigated. The Langmuir and Freundlich isotherms were used to model the metal sorption isotherms and the monolayer sorption capacities, as obtained by the Langmuir isotherm, were determined to be 13.9 mg/g and 11.1 mg/g for Cu2+ and Cd2+ respectively. Results have been compared with previous works on watermilfoils and are in accordance with those obtained on Myriophyllum spicatum. The sorption of the two metals was time-dependent and the kinetics fitted the pseudo-second-order equation well. The data were discussed in terms of ionic radii and HSAB concept. The phytotoxic effects assessed by classical (i.e. changes in biomass, node length) and photosynthetic pigments content endpoints have been investigated using chemometric techniques leading to an effect of cadmium onto photosynthetic pigments. PMID:17217998

Ngayila, Nadine; Basly, Jean-Philippe; Lejeune, Anne-Hélène; Botineau, Michel; Baudu, Michel

2007-02-15

260

New Measurements of the Densities of Copper, Nickel, and Iron Sulfide Liquids  

NASA Astrophysics Data System (ADS)

Density measurements of sulfide liquids in the Fe-Ni-Cu-S-O system were performed from 1150°C-1250°C under controlled oxygen and sulfur fugacities. Measurements were made using the modified single bob (MSB) Archimedean method using zirconia ceramic bobs and crucibles. A 0.005mm resolution micrometer was attached to an elevator, which raised the crucible and melt relative to the free-hanging, stationary bob. A 0.001 g resolution analytical balance connected to a laptop computer continuously recorded the buoyancy as a function of crucible elevation. Densities were calculated by converting elevation to immersed volume and regressing the slope of buoyancy versus volume immersed. log(fO2) in the experiments ranged from -7.8 to -12.6 and log(fS2) ranged from -0.9 to -3.3. 38 successful sulfide liquid density measurements were performed, with values ranging from 3.8 g/cc to 6.6 g/cc. Regression of the resulting data suggests that a simple linear volume mixing model is adequate to represent the compositional dependence of density in copper- and nickel-sulfide liquids. A moderate positive excess mixing volume appears to be justified in iron-sulfide liquids. This result, along with high derived partial molar volumes for oxygen and sulfur components, are qualitatively consistent with the suggestion that increasing pressure will partition oxygen and sulfur out of the sulfide liquid during planetary accretion. The MSB density measurement also provides information on the relative magnitude of gas-zirconia and sulfide-zirconia surface energies. Assuming most of the observed variation results from sulfide chemistry it appears that oxidizing conditions significantly decrease sulfide-zirconia surface energies (increase wetting). If we can extrapolate this result to silicate minerals, this would suggest that oxidizing conditions will decrease wetting angle and thus increase the potential for sulfide segregation during planetary formation. We hope to test this hypothesis soon. Our experience suggests that trivial modifications to the apparatus used in this study may provide an effective and reliable method for measuring liquid-solid surface energies in both sulfide and silicate systems. Such data would prove useful in both melt percolation and bubble nucleation and growth calculations.

Mioduszewski, L.; Kress, V. C.

2005-12-01

261

Copper and Iron Determination with [ N , N ?Bis(salicylidene)-2,2?-dimethyl-1,3-propanediaminato] in Edible Oils Without Digestion  

Microsoft Academic Search

A new method for the determination of copper(II) and iron(III) in liquid edible oils which does not require a digestion step\\u000a was developed. The suggested method involves extraction of metals with [N,N?-bis(salicylidene)-2,2?-dimethyl-1,3-propanediaminato] (LDM) followed by flame atomic absorption spectrometry measurement.\\u000a As a first step, metal complexes of copper(II) and iron(III) ions with LDM were investigated spectrophotometrically. After\\u000a the analytical properties

Eda Köse Baran; Sema Ba?dat Ya?ar

2010-01-01

262

Liquid chromatographic determination of cobalt(II), copper(II) and iron(II) using 2-thiophenaldehyde-4-phenyl-3-thiosemicarbazone as derivatizing reagent  

Microsoft Academic Search

The complexing reagent 2-thiophenaldehyde-4-phenyl-3-thiosemicarbazone (TAPT) was examined for high performance liquid chromatographic (HPLC) separations of cobalt(II), copper(II) and iron(II) or cobalt(II), nickel(II), iron(II), copper(II) and mercury(II) as metal chelates on a Microsorb C-18, 5-?m column (150×4.6 mm i.d.) (Rainin Instruments Woburn, MA, USA). The complexes were eluted isocratically with methanol:acetonitrile:water containing sodium acetate and tetrabutyl ammonium bromide (TBA). UV detection

M. Y Khuhawar; S. N Lanjwani

1998-01-01

263

Enhanced degradation of chlorobenzene in aqueous solution using microwave-induced zero-valent iron and copper particles.  

PubMed

Microwaves were applied to reduce the activation energy of chlorobenzene in aqueous solution and enhance its removal using nanoscale zero-valent iron (Fe0) or zero-valent copper (Cu0) particles as dielectric media. When Fe0 and Cu0 particles absorb microwave energy, the electrical potential difference causes the metal electrons to rotate faster, thus producing more heat. The microwave-irradiated metal particles reduced the chlorobenzene activation energy by 6.1 kJ/mol (13.3 kJ/mol versus 19.4 kJ/mol) for Fe0 and 5.4 kJ/mol (15.8 kJ/mol versus 21.4 kJ/mol) for Cu0 and enhanced the chlorobenzene removal 4.1 times (82.8% versus 20.4%) for Fe0 and 3.7 times (72.1% versus 19.5%) for Cu0. The Fe0 has a higher standard reduction potential than Cu0; it is capable of removing more chlorobenzene than Cu0 (82.8% versus 72.1%). Using the microwave-induced nano-scale iron or copper particle is effective in treating toxic organic substances, as demonstrated in this study. PMID:20669726

Lee, Chien-Li; Jou, Chih-Ju G; Wang, H Paul

2010-07-01

264

The release of zinc, copper, lead, and cadmium from the mineral tissue of teeth under the influence of soft drinks and sour-tasting food.  

PubMed

This study was carried out with the aim of identifying the effects of consuming sour-tasting food and refreshing drinks on the bone tissue of teeth among teenagers. The cumulative effect of a year-long exposure of teeth to the erosive effects of a model system of acidic media (citric acid, lactic acid, acetic acid, apple vinegar, lemonade, the soft drink Sprite, mineral water) was studied. The effects were registered based on the amount of released biometal ions, of zinc and copper, and toxic lead, during a period of 24 hr at room temperature, using the potentiometric stripping analysis. In the given time span, amounts ranging from 75 to 750 ppm of zinc, from 0.1 to 1.0 ppm of copper, and up to 1.5 ppm of lead were released from the dental matrix, while the release of cadmium was below the level of detection. The changes to the mineral structure of the bone tissue were monitored by the Fourier's transformation infrared spectroscopy and scanning electron microscopy technique. These studies have shown that under the influence of an acidic medium significant erosion to the tooth enamel ensues and that the eroded surfaces had a radius of 1-5 ?m. PMID:22141735

Nikoli?, Ružica; Kali?anin, Biljana; Krsti?, Nenad

2012-01-01

265

Origin of fluids in iron oxide–copper–gold deposits: constraints from ? 37 Cl, 87 Sr\\/ 86 Sr i and Cl\\/Br  

Microsoft Academic Search

The origin of the hypersaline fluids (magmatic or basinal brine?), associated with iron oxide (Cu–U–Au–REE) deposits, is controversial. We report the first chlorine and strontium isotope data combined with Cl\\/Br ratios of fluid inclusions from selected iron oxide–copper–gold (IOCG) deposits (Candelaria, Raúl–Condestable, Sossego), a deposit considered to represent a magmatic end member of the IOCG class of deposit (Gameleira), and

Massimo Chiaradia; Dave Banks; Robert Cliff; Robert Marschik; Antoine de Haller

2006-01-01

266

Iron  

MedlinePLUS

... shows that giving iron intravenously can improve some symptoms of heart failure. It is not yet known if taking an iron supplement by mouth would help.Attention deficit-hyperactivity disorder (ADHD). Developing research shows that taking iron sulfate ( ...

267

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

268

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

269

Copper and iron isotope fractionation during weathering and pedogenesis: Insights from saprolite profiles  

NASA Astrophysics Data System (ADS)

Iron and copper isotopes are useful tools to track redox transformation and biogeochemical cycling in natural environment. To study the relationships of stable Fe and Cu isotopic variations with redox regime and biological processes during weathering and pedogenesis, we carried out Fe and Cu isotope analyses for two sets of basalt weathering profiles (South Carolina, USA and Hainan Island, China), which formed under different climatic conditions (subtropical vs. tropical). Unaltered parent rocks from both profiles have uniform ?56Fe and ?65Cu values close to the average of global basalts. In the South Carolina profile, ?56Fe values of saprolites vary from -0.01‰ to 0.92‰ in the lower (reduced) part and positively correlate with Fe3+/?Fe (R2 = 0.90), whereas ?65Cu values are almost constant. By contrast, ?56Fe values are less variable and negatively correlate with Fe3+/?Fe (R2 = 0.88) in the upper (oxidized) part, where large (4.85‰) ?65Cu variation is observed with most samples enriched in heavy isotopes. In the Hainan profile formed by extreme weathering under oxidized condition, ?56Fe values vary little (0.05-0.14‰), whereas ?65Cu values successively decrease from 0.32‰ to -0.12‰ with depth below 3 m and increase from -0.17‰ to 0.02‰ with depth above 3 m. Throughout the whole profile, ?65Cu positively correlate with Cu concentration and negatively correlate with the content of total organic carbon (TOC). Overall, the contrasting Fe isotopic patterns under different redox conditions suggest redox states play the key controls on Fe mobility and isotope fractionation. The negative correlation between ?56Fe and Fe3+/?Fe in the oxidized part of the South Carolina profile may reflect addition of isotopically light Fe. This is demonstrated by leaching experiments, which show that Fe mineral pools extracted by 0.5 N HCl, representing poorly-crystalline Fe (hydr)-oxides, are enriched in light Fe isotopes. The systematic Cu isotopic variation in the Hainan profile reflects desorption and downward transport of isotopically heavy Cu, leaving the organically-bound Cu enriched in light isotope as supported by the negative correlation of ?65Cu with TOC (R2 = 0.88). The contrasting (mostly positive vs. negative) Cu isotopic signatures in the upper parts of these two profiles can be attributed to the different climatic conditions, e.g., high rainfall at a tropical climate in Hainan favors desorption and the development of organism, whereas relatively dry climate in South Carolina favors Cu re-precipitation from soil solutions and adsorption onto Fe (hydr)-oxides. Our results highlight the potential applications of Fe and Cu isotopes as great tracers of redox condition, ancient climate and biological cycling during chemical weathering and pedogenic translocation.

Liu, Sheng-Ao; Teng, Fang-Zhen; Li, Shuguang; Wei, Gang-Jian; Ma, Jing-Long; Li, Dandan

2014-12-01

270

Effects of contaminants in the Antarctic environment — potential of the gammarid amphipod crustacean Paramorea walkeri as a biological indicator for Antarctic ecosystems based on toxicity and bioacccumulation of copper and cadmium  

Microsoft Academic Search

This study provides information on LC50 toxicity tests and bioaccumulation of heavy metals in the nearshore Antarctic gammarid, Paramorea walkeri. The 4 day LC50 values were 970 ?g\\/l for copper and 670 ?g\\/l for cadmium. Net uptake rates and bioconcentration factors of these elements were determined under laboratory conditions. After 12 days of exposure to 30 ?g\\/l, the net uptake

S. Duquesne; M. Riddle; R. Schulz; M. Liess

2000-01-01

271

Superfund Record of Decision (EPA Region 9): Iron Mountain Mine, Redding, California, October 1986. Final report  

SciTech Connect

Iron Mountain Mine (IMM) was periodically mined for iron, silver, gold, copper, zinc, and pyrite. Rainfall, infiltrating into the underground mine workings mixes with ground water and the ore zone to produce sulfuric acid and high concentrations of zinc, cadmium, and copper. The resulting heavy metal-laden acidic waters, referred to as acid mine drainage (AMD), was eventually discharged through mine adits or ground water seepage into the Spring Creek watershed streams, Spring Creek Reservoir, and the Sacramento River. The primary contaminants of concern include: AMD, copper, cadmium, and zinc. The desired remedial action for this site was not selected due to excessive cost. Alternatives were proposed and are detailed in the report.

Not Available

1986-10-03

272

A multicommuted flow system for the determination of copper, chromium, iron and lead in lubricating oils with detection by flame AAS  

Microsoft Academic Search

In this work, a flow analysis procedure for the determination of copper, chromium, iron and lead in lubricating oils using flame AAS as detection technique is described. The flow manifold was designed to implement the multicommutation approach and it comprised three 3-way solenoid valves controlled by a personal computer. The flow system presented allowed to process the oil samples to

B. F. Reis; M. Knochen; G. Pignalosa; N. Cabrera; J. Giglio

2004-01-01

273

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

274

Effect of copper and iron on the oxidative flavor deterioration of ice cream  

E-print Network

aateinisation and hc: ogenisation can have a pronounced effect cn the occixrrence of oxidised flavor defeo+s. . sr&sauk and '. opps (39, C2) reported that, copper-protein complex was catalytically active in ths oxid itive f3&vcr development clnlsad hy a E... aateinisation and hc: ogenisation can have a pronounced effect cn the occixrrence of oxidised flavor defeo+s. . sr&sauk and '. opps (39, C2) reported that, copper-protein complex was catalytically active in ths oxid itive f3&vcr development clnlsad hy a E...

Miah, Md. Abdul Hamid

2012-06-07

275

Size- and temperature-dependent second-order optical effects in copper-doped cadmium iodide nanocrystals  

NASA Astrophysics Data System (ADS)

Size and temperature dependences of second-order optical effects in Cu-doped cadmium iodide nanocrystals are studied. A large enhancement of photoinduced second harmonic generation (PSHG) with decreasing thickness of the nanocrystals or temperature is observed. The PSHG is also found to be enhanced with increasing Cu doping. However, due to the formation of the metallic agglomerates, the PSHG for the crystals with high Cu contents decreases. The results are presented by discussing photoinduced kinetics of the electron-phonon anharmonic interaction and nanosized quantum confined effect, the crucial roles played in the observed effects.

Miah, M. Idrish

2008-09-01

276

Prokaryotic iron superoxide dismutase replaces cytosolic copper, zinc superoxide dismutase in protecting yeast cells against oxidative stress.  

PubMed

The iron superoxide dismutase (FeSOD) gene of Escherichia coli was cloned in Saccharomyces cerevisiae cells deficient in copper,zinc superoxide dismutase (Cu,ZnSOD). FeSOD replaced Cu,ZnSOD in protecting the yeast cells against oxidative stress. In the recombinant strains the FeSOD gene, which was under the transcriptional control of the yeast phosphoglycerate kinase gene promoter, was functionally expressed at two different levels on episomal and centromeric plasmids. Despite suppression of methionine and lysine auxotrophy, the higher level of FeSOD activity was more beneficial to growth of the mutant yeast cells only when these were exposed to higher levels of oxidative stress induced by paraquat or 100% oxygen. In the presence of paraquat, there was a novel stimulation of FeSOD activity. This was associated with a marked increase in catalase activity, and a decrease in glutathione reductase activity. PMID:9503146

Agius, D R; Bannister, W H; Balzan, R

1998-01-01

277

Hot gas desulfurization with sorbents containing oxides of zinc, iron, vanadium and copper. Quarterly technical progress report, July 1992  

SciTech Connect

The main objective of this research is to evaluate the desulfurization performance of novel sorbents consisting of different combinations of zinc, iron, vanadium and copper oxides; and to develop a sorbent which can reduce H{sub 2}S levels to less than 1 ppmv, which can stabilize zinc, making operations above 650{degrees}C possible, and which can produce economically recoverable amounts of elemental sulfur during regeneration. This objective will be accomplished by evaluating the sorbent performance using fixed-bed and TGA experiments supported by sorbent characterization at various reaction extents. In the seventh quarter, the screening of the promoted sorbents in the packed bed reactor was continued. The results of this work were presented at the 1992 University Coal Research Contractors, Review Conference at Pittsburgh, PA.

Akyurtlu, A.; Akyurtlu, J.F.

1992-09-01

278

Progressive Sorption and Oxidation\\/Hydrolysis of Fe(II) Affects Cadmium Immobilization by Bacteria-Iron Oxide Composites  

Microsoft Academic Search

Iron-bacteria composite suspensions were prepared by exposure of Anoxybacillus flavithermus cells to increasing concentrations of Fe cations under different degrees of oxidation. Cd immobilization was investigated during and after the synthesis of the iron-bacteria composites via scanning electron microscopy and isotherm sorption experiments conducted at varied ratios of total iron to bacteria (expressed by the variable ?, mg Fe per

Christopher J. Daughney; Mohamad Fakih; Xavier Châtellier

2011-01-01

279

Removal of copper and iron by polyurethane foam column in FIA system for the determination of nickel in pierced ring.  

PubMed

Polyurethane foam (PUF) mini-column was used to eliminate copper and iron for the determination of nickel in pierced rings. The PUF mini-column was connected to FIA system for on-line sorption of copper and iron in complexes form of CuSCN(+) and FeSCN(2+). For this season, the acid solution containing a mixture of Ni(II), Fe(III), Cu(II) and SCN(-) ions was firstly flew into the PUF column. Then, the percolated solution which Fe(III) and Cu(II) ions is separated from analysis was injected into FIA system to react with 4-(2-pyridylazo) resorcinol (PAR) reagent in basic condition which this method is called pH gradient technique. The Ni-PAR complexes obtained were measured theirs absorbance at 500nm by UV visible spectrophotometer. In this study, it was found that Cu(II) and Fe(III) were completely to form complexes with 400mmol/L KSCN and entirely to eliminate in acidic condition at pH 3.0. In the optimum condition of these experiments, the method provided the linear relationship between absorbance and the concentration of Ni(II) in the range from 5.00 to 30.00mg/L. Linear equation is y=0.0134x+0.0033 (R(2)=0.9948). Precision, assessed in the term of the relative standard deviation, RSD, and accuracy for multiple determinations obtained in values of 0.77-1.73% and 97.4%, respectively. The level of an average amount of Ni(II) in six piercing rings was evaluated to be 14.78mg/g. PMID:25281109

Vongboot, Monnapat; Suesoonthon, Monrudee

2015-01-01

280

1. Introduction Copper, along with iron active sites dominate the field of  

E-print Network

to oxida- tion of substrates (amine, galactose, and catechol oxidases),[6] activation for hydroxylation proteins include hemocya- nin, tyrosinase, and catechol oxidase.[5, 7] The binuclear copper centers, ascorbate oxidase, ceruloplasmin and Fet3p)[7] or proton pumping (cytochrome c oxidase, which also contains

Chen, Peng

281

Transcriptome Sequencing Identifies SPL7-Regulated Copper Acquisition Genes FRO4/FRO5 and the Copper Dependence of Iron Homeostasis in Arabidopsis[C][W  

PubMed Central

The transition metal copper (Cu) is essential for all living organisms but is toxic when present in excess. To identify Cu deficiency responses comprehensively, we conducted genome-wide sequencing-based transcript profiling of Arabidopsis thaliana wild-type plants and of a mutant defective in the gene encoding SQUAMOSA PROMOTER BINDING PROTEIN-LIKE7 (SPL7), which acts as a transcriptional regulator of Cu deficiency responses. In response to Cu deficiency, FERRIC REDUCTASE OXIDASE5 (FRO5) and FRO4 transcript levels increased strongly, in an SPL7-dependent manner. Biochemical assays and confocal imaging of a Cu-specific fluorophore showed that high-affinity root Cu uptake requires prior FRO5/FRO4-dependent Cu(II)-specific reduction to Cu(I) and SPL7 function. Plant iron (Fe) deficiency markers were activated in Cu-deficient media, in which reduced growth of the spl7 mutant was partially rescued by Fe supplementation. Cultivation in Cu-deficient media caused a defect in root-to-shoot Fe translocation, which was exacerbated in spl7 and associated with a lack of ferroxidase activity. This is consistent with a possible role for a multicopper oxidase in Arabidopsis Fe homeostasis, as previously described in yeast, humans, and green algae. These insights into root Cu uptake and the interaction between Cu and Fe homeostasis will advance plant nutrition, crop breeding, and biogeochemical research. PMID:22374396

Bernal, Maria; Casero, David; Singh, Vasantika; Wilson, Grandon T.; Grande, Arne; Yang, Huijun; Dodani, Sheel C.; Pellegrini, Matteo; Huijser, Peter; Connolly, Erin L.; Merchant, Sabeeha S.; Kramer, Ute

2012-01-01

282

The Phalabowra (Palabora) carbonatite-hosted magnetite–copper sulfide deposit, South Africa: an end-member of the iron-oxide copper–gold–rare earth element deposit group?  

Microsoft Academic Search

Olympic Dam-type iron-oxide copper–gold deposits are widely recognised in terrains with significant Palaeoproterozoic to\\u000a Mesoproterozoic granitic magmatism. Most researchers favour a magmatic association for these deposits, but none of the 100–2000?Mt\\u000a recognised copper-bearing deposits has a spatial and\\/or temporal relationship to an intrusive body of sufficient dimensions\\u000a to produce the hosting giant breccia and\\/or hydrothermal systems. In other words, if

David I. Groves; Noreen M. Vielreicher

2001-01-01

283

Iron  

MedlinePLUS

... several factors [ 1 , 3 , 8 , 11-15 ]. Storage levels of iron have the greatest influence on iron ... RDA), Adequate Intakes (AI), and Tolerable Upper Intake Levels (UL). The RDA recommends the average daily intake ...

284

Metallothioneins and energy budget indices in cadmium and copper exposed spiders Agelena labyrinthica in relation to their developmental stage, gender and origin.  

PubMed

The aim of our studies was to explain the role of metallothioneins (MTs) in the neutralization of excessive amounts of metals (essential: copper (Cu) and toxic: cadmium (Cd)) and to describe the energy status in metal-exposed spiders Agelena labyrinthica in relation to its developmental stage, gender and origin. Juvenile, female and male spiders were collected from three variously polluted habitats, transferred to the laboratory and exposed to the metals in their diet. Cu and Cd accumulation in the body and exuviae, bioaccumulation factor, percentage of metallothionein positive cells, MT concentration, percentage of cells with depolarized mitochondria, ATP concentration and ADP/ATP ratio were measured and calculated. Cu appeared to be regulated and its excess is eliminated via, among others, the molting process, while Cd was rather accumulated by the spiders. The level of MTs increased significantly mainly in females exposed to both metals, irrespectively of the pollution degree of their site of origin, indicating a defensive role of the proteins. In general, even if both the MT level and the energy status indices were positively correlated with Cd and Cu concentrations in the spider body, the energy status of A. labyrinthica did not seem disturbed. PMID:21620997

Babczy?ska, Agnieszka; Wilczek, Gra?yna; Wilczek, Piotr; Szuli?ska, El?bieta; Witas, Ilona

2011-09-01

285

Elevated CO2 levels affects the concentrations of copper and cadmium in crops grown in soil contaminated with heavy metals under fully open-air field conditions.  

PubMed

Elevated CO(2) levels and the increase in heavy metals in soils through pollution are serious problems worldwide. Whether elevated CO(2) levels will affect plants grown in heavy-metal-polluted soil and thereby influence food quality and safety is not clear. Using a free-air CO(2) enrichment (FACE) system, we investigated the impacts of elevated atmospheric CO(2) on the concentrations of copper (Cu) or cadmium (Cd) in rice and wheat grown in soil with different concentrations of the metals in the soil. In the two-year study, elevated CO(2) levels led to lower Cu concentrations and higher Cd concentrations in shoots and grain of both rice and wheat grown in the respective contaminated soil. Elevated CO(2) levels slightly but significantly lowered the pH of the soil and led to changes in Cu and Cd fractionation in the soil. Our study indicates that elevated CO(2) alters the distribution of contaminant elements in soil and plants, thereby probably affecting food quality and safety. PMID:21770376

Guo, Hongyan; Zhu, Jianguo; Zhou, Hui; Sun, Yuanyuan; Yin, Ying; Pei, Daping; Ji, Rong; Wu, Jichun; Wang, Xiaorong

2011-08-15

286

Sub-cellular partitioning of cadmium, copper, nickel and zinc in indigenous yellow perch (Perca flavescens) sampled along a polymetallic gradient.  

PubMed

Sub-cellular metal distributions were studied in indigenous yellow perch (Perca flavescens) collected from eight lakes located along a cadmium (Cd), copper (Cu), nickel (Ni) and zinc (Zn) concentration gradient. Ambient dissolved metal concentrations were measured to evaluate exposure and total hepatic metal concentrations were determined as a measure of metal bioaccumulation. Metal partitioning among potentially metal-sensitive fractions (cytosolic enzymes, organelles) and detoxified metal fractions (metallothionein) was determined after differential centrifugation of fish liver homogenates. Major proportions of hepatic Cd and Cu were found in the heat-stable cytosolic peptides and proteins fraction (HSP), a fraction including metallothioneins, whereas the potentially metal-sensitive heat-denaturable proteins fraction (HDP) was the largest contributor to the total Ni and Zn burdens. The concentrations of Cd, Cu and Ni (but not Zn) in each sub-cellular fraction increased along the metal contamination gradient, but the relative contributions of each fraction to the total burden of each of these metals remained generally constant. For these chronically exposed fish there was no threshold exposure concentration below which binding of Cd or Ni to the heat-denaturable protein fraction did not occur. The presence of Cd and Ni in the HDP fraction, even for low chronic exposure concentrations, suggests that metal detoxification was imperfect, i.e. that P. flavescens was subject to some metal-related stress even under these conditions. PMID:16430977

Giguère, Anik; Campbell, Peter G C; Hare, Landis; Couture, Patrice

2006-05-01

287

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

288

Neutron production in collisions between carbon nuclei of energy 2 GeV per nucleon and carbon, aluminum, copper, cadmium, and lead nuclei  

SciTech Connect

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 Degree-Sign , 53 Degree-Sign , and 90 Degree-Sign 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., E-mail: yurevich@sunhe.jinr.ru [Joint Institute for Nuclear Research (Russian Federation); Yakovlev, R. M.; Lyapin, V. G. [Khlopin Radium Institute (Russian Federation)

2012-02-15

289

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

290

Concentrations of PCBs, organochlorine pesticides and heavy metals (lead, cadmium, and copper) in fish from the Drôme river: potential effects on otters (Lutra lutra).  

PubMed

In this study samples of ten species of fish were analyzed for concentrations of organochlorine pesticides, PCBs and heavy metals (Pb, Cd, and Cu). Fish were captured using electric fishing on ten sites along the Drôme river (Rhône-Alpes region). Quantitative determination of the organochlorine and PCBs compounds was performed by gas chromatography-electron-capture detection (GC-ECD). The concentrations of heavy metals were determined by atomic absorption spectrophotometry. Samples contained detectable concentrations of lindane, PCBs, and heavy metals but at concentrations below the maximum residue limit (MRL). Non-parametric statistical analysis was performed to distinguish groups of sites with different levels of contamination. PCBs concentrations increased along the river with four groups of sites significantly different from each other. Cadmium concentrations were below the MRL. Lead contamination showed two groups significantly different and a repartition similar to PCBs. Copper contamination was correlated with the localization of vineyards. We assessed the potential effects of contamination the otter (Lutra lutra). The concentrations of all pollutants analyzed in fish sampled in this study are lower than the threshold values described in literature. The Drôme river is relatively unpolluted river, and the establishment of otter populations should not be affected by pollution. PMID:15964052

Mazet, Alexandra; Keck, Gérard; Berny, Philippe

2005-11-01

291

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

292

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

293

Iron, zinc and copper in the Alzheimer's disease brain: a quantitative meta-analysis. Some insight on the influence of citation bias on scientific opinion  

PubMed Central

Dysfunctional homeostasis of transition metals is believed to play a role in the pathogenesis of Alzheimer’s disease (AD). Although questioned by some, brain copper, zinc, and particularly iron overload are widely accepted features of AD which have led to the hypothesis that oxidative stress generated from aberrant homeostasis of these transition metals might be a pathogenic mechanism behind AD. This meta-analysis compiled and critically assessed available quantitative data on brain iron, zinc and copper levels in AD patients compared to aged controls. The results were very heterogeneous. A series of heavily cited articles from one laboratory reported a large increase in iron in AD neocortex compared to age-matched controls (p<0.0001) while seven laboratories failed to reproduce these findings reporting no significant difference between the groups (p=0.76). A more than three-fold citation bias was found to favor outlier studies reporting increases in iron and this bias was particularly prominent among narrative review articles. Additionally, while zinc was not significantly changed in the neocortex (p=0.29), copper was significantly depleted in AD (p=0.0003). In light of these findings, it will be important to re-evaluate the hypothesis that transition metal overload accounts for oxidative injury noted in AD. PMID:21600264

Schrag, Matthew; Mueller, Claudius; Oyoyo, Udochukwu; Kirsch, Wolff M.

2011-01-01

294

Co-Overexpression FIT with AtbHLH38 or AtbHLH39 in Arabidopsis-Enhanced Cadmium Tolerance via Increased Cadmium Sequestration in Roots and Improved Iron Homeostasis of Shoots1[W  

PubMed Central

Cadmium (Cd) is toxic to plant cells. Under Cd exposure, the plant displayed leaf chlorosis, which is a typical symptom of iron (Fe) deficiency. Interactions of Cd with Fe have been reported. However, the molecular mechanisms of Cd-Fe interactions are not well understood. Here, we showed that FER-like Deficiency Induced Transcripition Factor (FIT), AtbHLH38, and AtbHLH39, three basic helix-loop-helix transcription factors involved in Fe homeostasis in plants, also play important roles in Cd tolerance. The gene expression analysis showed that the expression of FIT, AtbHLH38, and AtbHLH39 was up-regulated in the roots of plants treated with Cd. The plants overexpressing AtbHLH39 and double-overexpressing FIT/AtbHLH38 and FIT/AtbHLH39 exhibited more tolerance to Cd exposure than wild type, whereas no Cd tolerance was observed in plants overexpressing either AtbHLH38 or FIT. Further analysis revealed that co-overexpression of FIT with AtbHLH38 or AtbHLH39 constitutively activated the expression of Heavy Metal Associated3 (HMA3), Metal Tolerance Protein3 (MTP3), Iron Regulated Transporter2 (IRT2), and Iron Regulated Gene2 (IREG2), which are involved in the heavy metal detoxification in Arabidopsis (Arabidopis thaliana). Moreover, co-overexpression of FIT with AtbHLH38 or AtbHLH39 also enhanced the expression of NICOTIANAMINE SYNTHETASE1 (NAS1) and NAS2, resulting in the accumulation of nicotiananamine, a crucial chelator for Fe transportation and homeostasis. Finally, we showed that maintaining high Fe content in shoots under Cd exposure could alleviate the Cd toxicity. Our results provide new insight to understand the molecular mechanisms of Cd tolerance in plants. PMID:22184655

Wu, Huilan; Chen, Chunlin; Du, Juan; Liu, Hongfei; Cui, Yan; Zhang, Yue; He, Yujing; Wang, Yiqing; Chu, Chengcai; Feng, Zongyun; Li, Junming; Ling, Hong-Qing

2012-01-01

295

Silencing the Menkes copper-transporting ATPase (Atp7a) gene in rat intestinal epithelial (IEC-6) cells increases iron flux via transcriptional induction of ferroportin 1 (Fpn1).  

PubMed

The Menkes copper-transporting ATPase (Atp7a) gene is induced in rat duodenum during iron deficiency, consistent with copper accumulation in the intestinal mucosa and liver. To test the hypothesis that ATP7A influences intestinal iron metabolism, the Atp7a gene was silenced in rat intestinal epithelial (IEC-6) cells using short hairpin RNA (shRNA) technology. Perturbations in intracellular copper homeostasis were noted in knockdown cells, consistent with the dual roles of ATP7A in pumping copper into the trans-Golgi (for cuproenzyme synthesis) and exporting copper from cells. Intracellular iron concentrations were unaffected by Atp7a knockdown. Unexpectedly, however, vectorial iron ((59)Fe) transport increased (?33%) in knockdown cells grown in bicameral inserts and increased further (?70%) by iron deprivation (compared with negative control shRNA-transfected cells). Additional experiments were designed to elucidate the molecular mechanism of increased transepithelial iron flux. Enhanced iron uptake by knockdown cells was associated with increased expression of a ferrireductase (duodenal cytochrome b) and activity of a cell-surface ferrireductase. Increased iron efflux from knockdown cells was likely mediated via transcriptional activation of the ferroportin 1 gene (by an unknown mechanism). Moreover, Atp7a knockdown significantly attenuated expression of an iron oxidase [hephaestin (HEPH); by ?80%] and membrane ferroxidase activity (by ?50%). Cytosolic ferroxidase activity, however, was retained in knockdown cells (75% of control cells), perhaps compensating for diminished HEPH activity. This investigation has thus documented alterations in iron homeostasis associated with Atp7a knockdown in enterocyte-like cells. Alterations in copper transport, trafficking, or distribution may underlie the increase in transepithelial iron flux noted when ATP7A activity is diminished. PMID:24174620

Gulec, Sukru; Collins, James F

2014-01-01

296

Bioconcentration patterns of zinc, copper, cadmium and lead in selected fish species from the Fox River, Illinois  

SciTech Connect

This study was conducted to determine if bioconcentration patterns were similar between four common essential and nonessential trace elements. The whole body concentrations of Zn, Cu, Cd and Pb were related to the whole body dry weights of blue-gill (Lepomis macrochirus), black crappie (Pomoxis nigromaculatus), black bullhead (Ictalurus melas), and yellow perch (Perca flavescens). Zinc, Cu, Cd, and Pb were selected because most studies of heavy metal concentrations in fish have examined one or more of these elements. These metals are often closely associated with each other as natural impurities or as alloys. Zinc and Cu are essential components of metallo-enzymes. Cadmium and Pb have not been shown to have essential functions in fishes, but rather inhibit biological systems and competitively interfere with Zn and Cu. The fish species were chosen on the basis of their importance as recreational and food species and their frequent use in both field and laboratory studies. Patterns of metal bioconcentrations with fish size were determined by simple linear regression.

Vinikour, W.S.; Goldstein, R.M.; Anderson, R.V.

1980-05-01

297

Bioaccumulation of lead, copper, iron, and zinc by fish in a transect of the Santa Catarina River in Cadereyta Jimenez, Nuevo Leon, Mexico  

SciTech Connect

Changes have been observed in the ichthyic species community, upriver in the San Juan River in Nuevo Leon, Mexico. A disappearance of Notropis amabilis, Notropis stramineus, Dionda episcopa and Campostoma anomalum and an increased mortality of Astyanax mexicanus, Lepomis macrochirus and Cichlasoma cyanoguttatum have been found. These changes were probably due to industrial and domestic discharges which produced high levels of lead, copper, iron and detergents in the water. The investigation reported here was done in order to detect the possible presence of lead, copper, iron and zinc in the river waters and also, to determine a probable bioaccumulation of these metals in fish species of the Santa Catarina River in the state of Nuevo Leon in northeastern Mexico, since this river transports domestic and industrial wastes of urban and suburban zones.

Not Available

1986-09-01

298

Cadmium sulfide-copper sulfide heterojunction cell research. Quarterly progress report, December 1, 1979-February 29, 1980  

SciTech Connect

Attempts have been continued to increase the short circuit current in cells of enhanced open circuit voltage. Both deposition of copper on the surface of the Cu/sub 2/S layer and hydrogen plasma treatments have been attempted. To date, no significant increase in ultimate current has been achieved. Various changes in cell production procedure have been made with significant improvements in reproducibility. Improvements in the structure of (CdZn)S layers and resulting cell properties have been achieved using modified substrates based on NiFe. Improvement have been made to the capacitance measuring systems with a consequent gain in resolution, accuracy and reproducibility. Structural studies of the electron beam deposited glass have revealed the presence of cracking and experiments have been carried out to determine the optimum deposition conditions for producing defect-free coatings.

None

1980-07-01

299

Reconnaissance-scale conceptual fuzzy-logic prospectivity modelling for iron oxide copper-gold deposits in the northern Fennoscandian Shield, Finland  

Microsoft Academic Search

The conceptual approach used in this study incorporates spatial analysis techniques for data integration and analysis to perform reconnaissance-scale mineral prospectivity mapping for iron oxide copper – gold (IOCG) mineralisation in Finland. The known IOCG occurrences in Finland are characterised by the following features: (i) an epigenetic magnetite-rich host-rock; (ii) an association of Fe – Cu – Au ± Co ± U; (iii) ore minerals comprising magnetite, chalcopyrite, pyrite or

V. Nykänen; D. I. Groves; V. J. Ojala; P. Eilu; S. J. Gardoll

2008-01-01

300

Tourmaline B-isotopes fingerprint marine evaporites as the source of high-salinity ore fluids in iron oxide copper-gold deposits, Carajás Mineral Province (Brazil)  

Microsoft Academic Search

The Carajás Mineral Province in northern Brazil containsa variety of world-class (>100 Mt ore) iron oxide copper-gold(IOCG) deposits, including the only Archean examples of thisdeposit class (e.g., the Igarapé Bahia\\/Alemãoand Salobo deposits). Tourmaline of schorl-dravite composition,a common gangue mineral in these deposits, precipitated shortlyprior to and after the ore assemblage. A boron isotope studyof texturally different tourmaline from three IOCG

Roberto Perez Xavier; Michael Wiedenbeck; Robert B. Trumbull; Ana M. Dreher; Lena V. S. Monteiro; Dieter Rhede; Carlos E. G. de Araújo; Ignacio Torresi

2008-01-01

301

Alterations in plasma essential trace elements selenium, manganese, zinc, copper, and iron concentrations and the possible role of these elements on oxidative status in patients with childhood asthma  

Microsoft Academic Search

The aim of the present study is to evaluate the status of plasma essential trace element selenium (Se), manganese (Mn), copper\\u000a (Cu), zinc (Zn), and iron (Fe) concentrations and the effect of these elements on oxidative status in patients with childhood\\u000a asthma. Plasma Se, Mn, Cu, and Zn concentrations were determined by atomic absorption spectrophotometry (AAS) and Fe concentrations,\\u000a malondialdehyde

A. Kocyigit; F. Armutcu; A. Gurel; B. Ermis

2004-01-01

302

Simultaneous high performance liquid chromatographic determination of vanadium, nickel, iron and copper in crude petroleum oils using bis(acetylpivalylmethane)ethylenediimine as a complexing reagent  

Microsoft Academic Search

A method is described for the simultaneous high performance liquid chromatographic (HPLC) determination of copper, iron, nickel and vanadium, based on complexation of analytes by bis(acetylpivalylmethane)ethylenediimine (H2APM2en) followed by solvent extraction and HPLC separation on a reversed-phase. C-18, 5 ?m column with UV detection at 260 nm. The method has been applied to the determination of metals in crude petroleum

M. Y. Khuhawar; S. N. Lanjwani

1996-01-01

303

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

304

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

305

Hydrothermal alteration, fluid inclusions and stable isotope systematics of the Alvo 118 iron oxide-copper-gold deposit, Carajás Mineral Province (Brazil): Implications for ore genesis  

Microsoft Academic Search

The Alvo 118 iron oxide-copper-gold (IOCG) deposit (170 Mt at 1.0 wt.% Cu, 0.3 g\\/t Au) lies in the southern sector of the Itacaúnas Shear Belt, Carajás Mineral Province, along a WNW-ESE-striking, 60-km-long shear zone, close to the contact of the ~2.76-Ga metavolcano-sedimentary Itacaiúnas Supergroup and the basement (~3.0 Ga Xingu Complex). The Alvo 118 deposit is hosted by mafic

Ignacio Torresi; Roberto Perez Xavier; Diego F. A. Bortholoto; Lena V. S. Monteiro

2011-01-01

306

Spatial and temporal zoning of hydrothermal alteration and mineralization in the Sossego iron oxide-copper-gold deposit, Carajás Mineral Province, Brazil: paragenesis and stable isotope constraints  

Microsoft Academic Search

The Sossego iron oxide-copper-gold deposit (245 Mt @ 1.1% Cu, 0.28 g\\/t Au) in the Carajás Mineral Province of Brazil consists of two major groups of orebodies (Pista-Sequeirinho-Baiano and Sossego-Curral) with distinct alteration assemblages that are separated from each other by a major high angle fault. The deposit is located along a regional WNW-ESE-striking shear zone that defines the contact

Lena V. S. Monteiro; Roberto P. Xavier; Emerson R. de Carvalho; Murray W. Hitzman; Craig A. Johnson; Carlos Roberto de Souza Filho; Ignácio Torresi

2008-01-01

307

Iron prevents ascorbic acid (vitamin C) induced hydrogen peroxide accumulation in copper contaminated drinking water.  

PubMed

Ascorbic acid (vitamin C) induced hydrogen peroxide (H(2)O(2)) formation was measured in household drinking water and metal supplemented Milli-Q water by using the FOX assay. Here we show that ascorbic acid readily induces H(2)O(2) formation in Cu(II) supplemented Milli-Q water and poorly buffered household drinking water. In contrast to Cu(II), iron was not capable to support ascorbic acid induced H(2)O(2) formation during acidic conditions (pH: 3.5-5). In 12 out of the 48 drinking water samples incubated with 2 mM ascorbic acid, the H(2)O(2) concentration exceeded 400 microM. However, when trace amounts of Fe(III) (0.2 mg/l) was present during incubation, the ascorbic acid/Cu(II)-induced H(2)O(2) accumulation was totally blocked. Of the other common divalent or trivalent metal ions tested, that are normally present in drinking water (calcium, magnesium, zinc, cobalt, manganese or aluminum), only calcium and magnesium displayed a modest inhibitory activity on the ascorbic acid/Cu(II)-induced H(2)O(2) formation. Oxalic acid, one of the degradation products from ascorbic acid, was confirmed to actively participate in the iron induced degradation of H(2)O(2). Ascorbic acid/Cu(II)-induced H(2)O(2) formation during acidic conditions, as demonstrated here in poorly buffered drinking water, could be of importance in host defense against bacterial infections. In addition, our findings might explain the mechanism for the protective effect of iron against vitamin C induced cell toxicity. PMID:16298750

Jansson, Patric J; Lindqvist, Christer; Nordström, Tommy

2005-11-01

308

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

309

Fast ultrasound-assisted extraction of copper, iron, manganese and zinc from human hair samples prior to flow injection flame atomic absorption spectrometric detection.  

PubMed

A dynamic ultrasound-assisted extraction procedure utilizing diluted nitric acid was developed for the determination of copper, iron, manganese and zinc in human hair taken from workers in permanent contact with a polluted environment. The extraction unit of the dynamic ultrasound-assisted extraction system contains a minicolumn into which a specified amount of hair (5-50 mg) is placed. Once inserted into the continuous manifold, trace metals were extracted at 3 mL min(-1) with 3 mol L(-1) nitric acid under the action of ultrasound for 2 min for zinc and 3 min for copper, iron and manganese determination, and using an ultrasonic water-bath temperature of 70 degrees C for zinc and 80 degrees C for copper, iron and manganese determination. The system permits the direct analysis of hair and yields concentrations with relative standard deviations of <3% (n = 11). The applicability of the procedure was verified by analysing human hair samples from workers exposed to welding fumes, and its accuracy was assessed through comparison with a conventional sample dissolution procedure and the use of a certified reference material (BCR 397, human hair). PMID:17404713

Yebra-Biurrun, M C; Cespón-Romero, R M

2007-06-01

310

Coumarin-Based Fluorescent Probes for Dual Recognition of Copper(II) and Iron(III) Ions and Their Application in Bio-Imaging  

PubMed Central

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?5 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

Garcia-Beltran, Olimpo; Cassels, Bruce K.; Perez, Claudio; Mena, Natalia; Nunez, Marco T.; Martinez, Natalia P.; Pavez, Paulina; Aliaga, Margarita E.

2014-01-01

311

Synthesis and properties of ternary GIC with iron or copper chlorides  

NASA Astrophysics Data System (ADS)

The variety of graphite intercalation compounds (GIC) is provided by the possibility to obtain ternary intercalation (TGIC) compounds containing two or more intercalates. A wide range of metal chlorides (FeCl3, AlCl3, CuCl2, NiCl2) and Brönsted acids (HNO3, CH3COOH, H2SO4) are generally used as intercalates. Iron chloride intercalation into the graphite leads to the formation of binary GIC with composition C6nFeCl3. Iron chloride acts as intercalate and oxidizer for the graphite matrix. Oxidation ability is due to the evolving of chlorine gas. Intercalation of CuCl2 requires harder conditions and occurs only with Cl2 presence. Co-intercalation GICs with FeCl3 and CH3COOH were synthesized by electrochemical graphite oxidation in the mixed electrolyte. Bi-intercalation GICs containing CuCl2 and H2SO4 were obtained by successive graphite intercalation with metal chloride and acid. All the synthesized compounds were investigated by physicochemical analysis. New ternary intercalation compounds with the FeCl3 CH3COOH mixture or CuCl2 H2SO4 one were synthesized. The correlation between intercalation features and reagents intercalation ability was shown.

Shornikova, O. N.; Dunaev, A. V.; Maksimova, N. V.; Avdeev, V. V.

2006-05-01

312

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

313

Acute effect of copper and cadmium exposure on the expression of heat shock protein 70 in the Cyprinidae fish Tanichthys albonubes.  

PubMed

A full sequence of TaHSP70 (heat shock protein 70 of Tanichthys albonubes) was amplified which was 2398 bp, including an open reading frame (ORF) of 1392 bp encoding a polypeptide of 643 amino acids with all three HSP70 family signatures and cytosolic motif of EEVD. Genomic DNA structure analysis revealed that the TaHSP70 gene contained one intron in 5'UTR. BLAST analysis revealed that the TaHSP70 gene shared high similarity with other known HSP70 genes. The alignment of inferred amino acid sequences also showed high degrees of similarity among the homologues. There was a basal mRNA expression of TaHSP70 in the different tissues from the non-exposed T. albonubes and the highest expression level in the liver. To investigated the time- and dose-dependent relationship of the expression of TaHSP70 following exposure to heavy metals, T. albonubes were exposed to 2(-1) 96 h-LC50 (0.027 mg L(-1)), 4(-1) 96 h-LC50 (0.0135 mg L(-1)) of copper and 2(-1) 96 h-LC50 (2.31 mg L(-1)), 4(-1) 96 h-LC50 (1.15 mg L(-1)) of cadmium for 96 h. Hsp70 expression relative to the control was analyzed by Quantitative real-time PCR and Western blotting. The results indicated that there were a dose-dependent expression pattern and an exposure time effect in the liver responded to heavy metal stress. Interestingly, TaHSP70 gene expressions did not show consistent changes between transcription and translation levels. Taken together, the dynamics of TaHSP70 expression observed provided important insight into heavy metal stress, heat shock protein activity, and the potential ways to monitor the chronic stressors in T. albonubes culture environments. PMID:23402923

Jing, Jing; Liu, Haichao; Chen, Huihui; Hu, Sifan; Xiao, Kan; Ma, Xufa

2013-05-01

314

I. Electronic properties of cyclopentadienyl ytterbium complexes. II. Copper (I) complexes as synthetic precursors to cadmium sulfide/cuprous sulfide photovoltaic cells  

SciTech Connect

A brief review of organometallic lanthanide chemistry is given. Adduct formation of tris(cyclopentadienyl)ytterbium with a variety of Lewis bases in non-coordinating solvents can be quantitatively monitored by electronic absorption and emission spectral changes. Resulting spectral changes have been used to postulate the energy manifolds for the /sup 2/F/sub (7/2)/ and /sup 2/F/sub (5/2)/ states of the adducts. The fundamental principles of p-n junctions are discussed alongf with a brief review of cadmium sulfide/cuprous sulfide solar cells. Topics include the properties of semiconductors, (the properties of) p-n junction, and solar cells; fabrication of CdS/Cu/sub 2/S solar cells; and characterization of CdS/Cu/sub 2/S solar cells. Amyl alcohol solutions of the bis(2,2'-biquinoline) copper (I) cation, I, react with single-crystal, n-type CdS to yield n-CdS/p-Cu/sub 2/S heterojunctions. The intense visible absorption band of I (lambda/sub max/ 545 nm; epsilon approx.6300 M/sup -1/ cm/sup -1/ at 25/sup 0/C) provides an in situ spectrophotometric probe of heterojunction formation: spectral changes can be correlated with the extent of reaction. Kinetic studies using the nitrate salt of I reveal that initial reaction rates are directly proportional to Cds macroscopic surface area, first order in concentration of I, and temperature dependent with an apparent activation energy of 13 +/- 2 kcal/mol between 60 and 90/sup 0/C. Mechanistic aspects of the reaction are discussed.

Schlesener, C.J.

1982-01-01

315

Biochemical responses of juvenile European sturgeon, (Huso huso) to a sub-lethal level of copper and cadmium in freshwater and brackish water environments  

PubMed Central

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

2013-01-01

316

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. PMID:21841973

Rodney, Eric; Herrera, Pedro; Luxama, Juan; Boykin, Mark; Crawford, Alisa; Carroll, Margaret A.; Catapane, Edward J.

2011-01-01

317

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

318

Effects of chronic light/dark cycle on iron zinc and copper levels in different brain regions of rats.  

PubMed

In this study, we aimed to investigate whether chronic shift in light/dark cycle alters brain trace element concentrations. For this purpose, 20 male Wistar albino adult rats were weighed and randomly divided into three groups. The first group (n?=?6) was the control and had been subjected to 12/12-h light/dark cycle for 30 days. The second group (n?=?7) was subjected to 6/18-h light/dark cycle for 15 days, and the third group (n?=?7) was also subjected to 6/18-h light/dark cycle for 15 days and then returned to normal 12/12-h light/dark cycle for 15 days. When light/dark cycle protocols were completed, tissue specimens of the frontal lobe, temporal lobe, and brain stem were collected. Iron (Fe), zinc (Zn), and copper (Cu) concentrations of the frontal lobe, temporal lobe, and brain stem were determined by an atomic absorption spectrophotometer. When compared with controls, Fe levels of the temporal lobe significantly increased in 6/18-h light/dark cycle group (p?

Karakoc, Yunus; Buruk, Mehmet Seyfi; Aktan, Burak; Kirvar, Ramazan; Erdogan, Songul; Sahbaz, Mehmet Akif; Aksoy, Sevket; Gulyasar, Tevfik

2011-12-01

319

Copper stable isotopes as tracers of metal-sulphide segregation and fractional crystallisation processes on iron meteorite parent bodies  

NASA Astrophysics Data System (ADS)

We report high precision Cu isotope data coupled with Cu concentration measurements for metal, troilite and silicate fractions separated from magmatic and non-magmatic iron meteorites, analysed for Fe isotopes (? 57Fe; permil deviation in 57Fe/ 54Fe relative to the pure iron standard IRMM-014) in an earlier study ( Williams et al., 2006). The Cu isotope compositions (? 65Cu; permil deviation in 65Cu/ 63Cu relative to the pure copper standard NIST 976) of both metals (? 65Cu M) and sulphides (? 65Cu FeS) span much wider ranges (-9.30 to 0.99‰ and -8.90 to 0.63‰, respectively) than reported previously. Metal-troilite fractionation factors (? 65Cu M-FeS = ? 65Cu M - ? 65Cu FeS) are variable, ranging from -0.07 to 5.28‰, and cannot be explained by equilibrium stable isotope fractionation coupled with either mixing or reservoir effects, i.e. differences in the relative proportions of metal and sulphide in the meteorites. Strong negative correlations exist between troilite Cu and Fe (? 57Fe FeS) isotope compositions and between metal-troilite Cu and Fe (? 57Fe M-FeS) isotope fractionation factors, for both magmatic and non-magmatic irons, which suggests that similar processes control isotopic variations in both systems. Clear linear arrays between ? 65Cu FeS and ? 57Fe FeS and calculated Cu metal-sulphide partition coefficients (D Cu = [Cu] metal/[Cu] FeS) are also present. A strong negative correlation exists between ? 57Fe M-FeS and D Cu; a more diffuse positive array is defined by ? 65Cu M-FeS and D Cu. The value of D Cu can be used to approximate the degree of Cu concentration equilibrium as experimental studies constrain the range of D Cu between Fe metal and FeS at equilibrium to be in the range of 0.05-0.2; D Cu values for the magmatic and non-magmatic irons studied here range from 0.34 to 1.11 and from 0.04 to 0.87, respectively. The irons with low D Cu values (closer to Cu concentration equilibrium) display the largest ? 57Fe M-FeS and the lowest ? 65Cu M-FeS values, whereas the converse is observed in the irons with large values D Cu that deviate most from Cu concentration equilibrium. The magnitudes of Cu and Fe isotope fractionation between metal and FeS in the most equilibrated samples are similar: 0.25 and 0.32‰/amu, respectively. As proposed in an earlier study ( Williams et al., 2006) the range in ? 57Fe M-FeS values can be explained by incomplete Fe isotope equilibrium between metal and sulphide during cooling, where the most rapidly-cooled samples are furthest from isotopic equilibrium and display the smallest ? 57Fe M-FeS and largest D Cu values. The range in ? 65Cu M-FeS, however, reflects the combined effects of partial isotopic equilibrium overprinting an initial kinetic signature produced by the diffusion of Cu from metal into exsolving sulphides and the faster diffusion of the lighter isotope. In this scenario, newly-exsolved sulphides initially have low Cu contents (i.e. high D Cu) and extremely light ? 65Cu FeS values; with progressive equilibrium and fractional crystallisation the Cu contents of the sulphides increase as their isotopic composition becomes less extreme and closer to the metal value. The correlation between ? 65Cu M-FeS and ? 57Fe M-FeS is therefore a product of the superimposed effects of kinetic fractionation of Cu and incomplete equilibrium between metal and sulphide for both isotope systems during cooling. The correlations between ? 65Cu M-FeS and ? 57Fe M-FeS are defined by both magmatic and non-magmatic irons record fractional crystallisation and cooling of metallic melts on their respective parent bodies as sulphur and chalcophile elements become excluded from crystallised solid iron and concentrated in the residual melt. Fractional crystallisation processes at shallow levels have been implicated in the two main classes of models for the origin of the non-magmatic iron meteorites; at (i) shallow levels in impact melt models and (ii) at much deeper levels in models where the non-magmatic irons represent metallic melts that crystallised within the in

Williams, Helen M.; Archer, Corey

2011-06-01

320

Method for selective recovery of cadmium from cadmium-bearing waste  

Microsoft Academic Search

A method for the selective recovery of cadmium, nickel and cobalt from a nickel--cadmium battery waste comprises the following steps: (A) leaching the waste with an ammoniacal carbonate solution to form an aqueous ammoniacal carbonate solution containing cadmium, nickel and cobalt (II) ammine complexes and a leaching residue--any iron in the waste is in the leaching residue; (B) adding air

H. Reinhardt; H. D. Ottertun; J. H. A. Rydberg

1977-01-01

321

Microstructural Evolution and Mechanical Properties of Fusion Welds in an Iron-Copper-Based Multicomponent Steel  

NASA Astrophysics Data System (ADS)

NUCu-140 is a copper-precipitation-strengthened steel that exhibits excellent mechanical properties with a relatively simple chemical composition and processing schedule. As a result, NUCu-140 is a candidate material for use in many naval and structural applications. Before NUCu-140 can be implemented as a replacement for currently used materials, the weldability of this material must be determined under a wide range of welding conditions. This research represents an initial step toward understanding the microstructural and mechanical property evolution that occurs during fusion welding of NUCu-140. Microhardness traverses and tensile testing using digital image correlation show local softening in the heat-affected zone (HAZ). Microstructural characterization using light optical microscopy (LOM) revealed very few differences in the softened regions compared with the base metal. Local-electrode atom-probe (LEAP) tomography demonstrates that local softening occurs as a result of dissolution of the Cu-rich precipitates. MatCalc kinetic simulations (Vienna, Austria) were combined with welding heat-flow calculations to model the precipitate evolution within the HAZ. Reasonably good agreement was obtained between the measured and calculated precipitate radii, number density, and volume fraction of the Cu-rich precipitates in the weld. These results were used with a precipitate-strengthening model to understand strength variations within the HAZ.

Farren, Jeffrey D.; Hunter, Allen H.; Dupont, John N.; Seidman, David N.; Robino, Charles V.; Kozeschnik, Ernst

2012-11-01

322

Adsorption and decomposition of hydrazine on metal films of iron, nickel, and copper  

SciTech Connect

The interaction of hydrazine with evaporated metal films of Fe, Ni, and Cu has been investigated in the temperature range 243-393 K. Dissociative chemisorption of hydrazine occurred on Fe and Ni films at 243 K with liberation of NH/sub 3/, N/sub 2/, and H/sub 2/ gases. Adsorption on Cu film at the same temperature was molecular and a significant fraction of the adsorption was reversible. Two different mechanisms have been suggested for the adsorption and the subsequent formation of the decomposition products. Ammonia was the main gaseous product of hydrazine decomposition on the films at all temperatures. The desorption of the products was more extensive in the case of Ni film as compared with the other two metals. The activation energy (E/sub a/) of hydrazine adsorption as well as the pre-exponential factor (A) in the rate equation remained independent of extent of adsorption. The relationship which was found to exist between the values of log A and those of E/sub a/ indicated the operation of a compensation effect in the hydrazine adsorption on the films. Copper film was found to have a greater capability for hydrazine adsorption than the other two films. The geometric requirements for appropriate hydrazine adsorption on this metal are probably more satisfied than on the other two metals. 27 references, 6 figures, 4 tables.

Al-Haydari, Y.K.; Saleh, J.M.; Matloob, M.H.

1985-07-18

323

Accumulation and fractionation of copper, iron, manganese, and zinc in calcareous soils amended with composts.  

PubMed

Amending soils with compost may lead to accumulation of metals and their fractions at various concentrations in the soil profile. The objectives of this study were to determine 1) the accumulation of Cu, Fe, Mn, and Zn with depth and 2) the distribution of water soluble, exchangeable, carbonate, Fe-Mn oxides, organic and residual forms of each metal in soils amended with MSW compost, co-compost, biosolids compost and inorganic fertilizer (as control). Total concentrations of Cu, Fe, Mn and Zn were concentrated in the 0-22 cm soil layer and scant in the rock layer. These metals were in the decreasing order of Fe > Mn > Zn > or = Cu. Copper, Fe, and Zn were predominantly in the residual form followed by fractions associated with Fe-Mn oxides, carbonate, organic, exchangeable and water soluble in all treatments except MSW compost amended soil where the organic fraction was higher than the carbonate fraction. In fertilizer, co-compost and biosolids compost treated soils Mn concentrated mainly in the Fe-Mn oxides form followed by residual, carbonate, and organic forms whereas, in MSW compost treated soil the same pattern occurred except that Mn organic fraction was higher than that in the carbonate form. The MSW compost has a greater potential to be used as a soil amendment to supply plants with Cu, Mn and Zn than other treatments in calcareous soils of south Florida. PMID:11409501

Zinati, G M; Li, Y; Bryan, H H

2001-03-01

324

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

325

Molecular mechanisms of the epithelial transport of toxic metal ions, particularly mercury, cadmium, lead, arsenic, zinc, and copper. Progress report, January 1, 1977December 31, 1977. [In chickens  

Microsoft Academic Search

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 investigated in some detail.

1977-01-01

326

Effect of Copper and Nickel on the Transformation Kinetics of Austempered Ductile Iron  

NASA Astrophysics Data System (ADS)

The kinetics of reaction occurring during the austempering treatment of ductile iron (DI) containing different additions of Cu and Ni was investigated in this work. DI bars were heat treated in an instrumented dilatometer in order to follow the exhibited transformation kinetics. The dilatometric results indicated that the addition of Cu alone did not have a significant effect on the incubation times for the austempering transformation. Also, the addition of both, Cu and Ni resulted in a significant effect on reducing the transformation rates. It was found that the austempering process is characterized by two clearly distinguished transformation stages. In the initial stage, the addition of Cu, and to a greater extent, additions of both Cu and Ni led to reductions in the transformation rates shifting the maximum transformation rate values toward longer times. The outcome of this work indicates that during the first stage of austempering, nucleation of the ferrite plates occurs via a diffusionless mechanism while their growth is diffusion controlled. Moreover, after the maximum in the transformation rate has been reached, the growth of ferrite plates becomes dominant with the rate-limiting step becoming the diffusion of C into the surrounding austenite. A qualitative model for the austempering transformation is proposed in this work to account for the experimental observations.

Górny, Marcin; Tyra?a, Edward; Lopez, Hugo

2014-10-01

327

The long-term effects of copper surface area on menstrual blood loss and iron status in women fitted with an IUD.  

PubMed

The long-term effects of copper surface area on menstrual blood loss (MBL) and iron status (hemoglobin, hematocrit, red cell count and indices, and serum ferritin) were evaluated in 25 healthy women who were observed for a period of 3 years following insertion of an intrauterine device. MBL was determined objectively by the alkaline hematin method. The women (mean age 37.2 +/- 1.6 yr, range 27-46 yr) were fitted with a Multiload intrauterine device (IUD) with a copper surface area of either 250 mm2 (MLCu-250, n = 13) or 375 mm2 (MLCu-375, n = 12). MBL prior to IUD insertion was 55 +/- 8 ml for women subsequently fitted with a MLCu-250 and 59 +/- 9 ml for women fitted with a MLCu-375. An increase in MBL was recorded at all measurement points following IUD insertion (MLCu-250/MLCu-375: 3 months: 55/49%; 6 months: 58/49%; 12 months: 64/41%; 24 months: 55/49%; 36 months: 47/39%, NS). There were no significant differences in iron status parameters before IUD insertion between groups nor were there any significant changes recorded in any of these parameters after IUD insertion. Our findings that the increase in copper surface area from 250 mm2 to 375 mm2 had no effect on MBL were thus substantiated by the hematological findings. Based on the results of the present study, women from developed countries apparently tolerate an increased MBL of approximately 45% without developing anemia. Iron stores were unchanged indicating an adequate adaptive increase in intestinal iron absorption. PMID:8275696

Larsson, G; Milsom, I; Jonasson, K; Lindstedt, G; Rybo, G

1993-11-01

328

Iron(II) and copper(I) coordination polymers: electrochromic materials with and without chiroptical properties.  

PubMed

The electrochemical and optical properties of films prepared from two different Fe(II) coordination polymers (TPT[Fe(II)TPT](n)(PF(6))(2)(n) (TPT = terpyridine-phenyl-terpyridine) and CTPCT[Fe(II)CTPCT](n)(PF(6))(2)(n) (CTPCT = chiral terpyridine-phenyl-chiral terpyridine)) and a coordination polymer based on Cu(I) metal centers (PDP[Cu(I)PDP](n)(BF(4))(n)) (PDP = phenanthroline-dodecane-phenanthroline) have been studied. The oxidation of a PDP[Cu(I)PDP](n)(BF(4))(n) film coated on an indium-tin oxide (ITO) electrode by stepping the potential from 0.0 to +1.4 V vs Ag/AgCl led not only to the complete bleaching of the absorption in the visible region of the spectrum within 5 min but also to a redox-induced dissociation and dissolution of the polymer. The reverse reaction of binding and reassembling the polymer at the electrode surface, upon stepping the potential back to 0.0 V, occurred with a rate which was at least 1 order of a magnitude slower. In contrast, the bis(2,2':6',2' '-terpyridine)iron(II)-based redox polymers TPT[Fe(II)TPT](n)(PF(6))(2)(n) and CTPCT[Fe(II)CTPCT](n)(PF(6))(2)(n), during similar spectroelectrochemical experiments, not only exhibited a dramatically enhanced switching rate but also displayed symmetric switching kinetics. The films did not show signs of deterioration over 150 switching cycles. Additionally, in an effort to assemble an electrochromic device with chiroptical properties, the electrochromism of films generated from the enantiomerically pure CTPCT[Fe(II)CTPCT](n)(PF(6))(2)(n) polymer was studied through circular dichroism. PMID:12844311

Bernhard, Stefan; Goldsmith, Jonas I; Takada, Kazutake; Abruña, Héctor D

2003-07-14

329

Solid state 31phosphorus nuclear magnetic resonance of iron-, manganese-, and copper-containing synthetic hydroxyapatites.  

PubMed

The incorporation of micronutrients into synthetic hydroxyapatite (SHA) is proposed for slow release of these nutrients to crops in the National Aeronautics and Space Administration's (NASA's) Advanced Life Support (ALS) program for Lunar or Martian outposts. Solid state 31P nuclear magnetic resonance (NMR) was utilized to examine the paramagnetic effects of Fe3+, Mn2+, and Cu2+ to determine if they were incorporated into the SHA structure. Separate Fe3+, Mn2+, and Cu2+ containing SHA materials along with a transition metal free SHA (pure-SHA) were synthesized using a precipitation method. The proximity (<1 nm) of the transition metals to the 31P nuclei of SHA were apparent when comparing the integrated 31P signal intensities of the pure-SHA (87 arbitrary units g-1) with the Fe-, Mn-, and Cu-SHA materials (37-71 arbitrary units g-1). The lower integrated 31P signal intensities of the Fe-, Mn-, and Cu-SHA materials relative to the pure-SHA suggested that Fe3+, Mn2+, and Cu2+ were incorporated in the SHA structure. Further support for Fe3+, Mn2+, and Cu2+ incorporation was demonstrated by the reduced spin-lattice relaxation constants of the Fe-, Mn-, and Cu-SHA materials (T'=0.075-0.434s) relative to pure-SHA (T1=58.4s). Inversion recovery spectra indicated that Fe3+, Mn2+, and Cu2+ were not homogeneously distributed about the 31P nuclei in the SHA structure. Extraction with diethylene-triamine-penta-acetic acid (DTPA) suggested that between 50 and 80% of the total starting metal concentrations were incorporated in the SHA structure. Iron-, Mn-, and Cu-containing SHA are potential slow release sources of Fe, Mn, and Cu in the ALS cropping system. PMID:12088032

Sutter, B; Taylor, R E; Hossner, L R; Ming, D W

2002-01-01

330

Copper and Iron Homeostasis in Plants: The Challenges of Oxidative Stress  

PubMed Central

Abstract Significance: Photosynthesis, the process that drives life on earth, relies on transition metal (e.g., Fe and Cu) containing proteins that participate in electron transfer in the chloroplast. However, the light reactions also generate high levels of reactive oxygen species (ROS), which makes metal use in plants a challenge. Recent Advances: Sophisticated regulatory networks govern Fe and Cu homeostasis in response to metal ion availability according to cellular needs and priorities. Molecular remodeling in response to Fe or Cu limitation leads to its economy to benefit photosynthesis. Fe toxicity is prevented by ferritin, a chloroplastic Fe-storage protein in plants. Recent studies on ferritin function and regulation revealed the interplay between iron homeostasis and the redox balance in the chloroplast. Critical Issues: Although the connections between metal excess and ROS in the chloroplast are established at the molecular level, the mechanistic details and physiological significance remain to be defined. The causality/effect relationship between transition metals, redox signals, and responses is difficult to establish. Future Directions: Integrated approaches have led to a comprehensive understanding of Cu homeostasis in plants. However, the biological functions of several major families of Cu proteins remain unclear. The cellular priorities for Fe use under deficiency remain largely to be determined. A number of transcription factors that function to regulate Cu and Fe homeostasis under deficiency have been characterized, but we have not identified regulators that mediate responses to excess. Importantly, details of metal sensing mechanisms and cross talk to ROS-sensing mechanisms are so far poorly documented in plants. Antioxid. Redox Signal. 19, 919–932. PMID:23199018

Pilon, Marinus

2013-01-01

331

Solid state 31phosphorus nuclear magnetic resonance of iron-, manganese-, and copper-containing synthetic hydroxyapatites  

NASA Technical Reports Server (NTRS)

The incorporation of micronutrients into synthetic hydroxyapatite (SHA) is proposed for slow release of these nutrients to crops in the National Aeronautics and Space Administration's (NASA's) Advanced Life Support (ALS) program for Lunar or Martian outposts. Solid state 31P nuclear magnetic resonance (NMR) was utilized to examine the paramagnetic effects of Fe3+, Mn2+, and Cu2+ to determine if they were incorporated into the SHA structure. Separate Fe3+, Mn2+, and Cu2+ containing SHA materials along with a transition metal free SHA (pure-SHA) were synthesized using a precipitation method. The proximity (<1 nm) of the transition metals to the 31P nuclei of SHA were apparent when comparing the integrated 31P signal intensities of the pure-SHA (87 arbitrary units g-1) with the Fe-, Mn-, and Cu-SHA materials (37-71 arbitrary units g-1). The lower integrated 31P signal intensities of the Fe-, Mn-, and Cu-SHA materials relative to the pure-SHA suggested that Fe3+, Mn2+, and Cu2+ were incorporated in the SHA structure. Further support for Fe3+, Mn2+, and Cu2+ incorporation was demonstrated by the reduced spin-lattice relaxation constants of the Fe-, Mn-, and Cu-SHA materials (T'=0.075-0.434s) relative to pure-SHA (T1=58.4s). Inversion recovery spectra indicated that Fe3+, Mn2+, and Cu2+ were not homogeneously distributed about the 31P nuclei in the SHA structure. Extraction with diethylene-triamine-penta-acetic acid (DTPA) suggested that between 50 and 80% of the total starting metal concentrations were incorporated in the SHA structure. Iron-, Mn-, and Cu-containing SHA are potential slow release sources of Fe, Mn, and Cu in the ALS cropping system.

Sutter, B.; Taylor, R. E.; Hossner, L. R.; Ming, D. W.

2002-01-01

332

Solid phase extraction of trace amounts of silver, cadmium, copper, mercury, and lead in various food samples based on ethylene glycol bis-mercaptoacetate modified 3-(trimethoxysilyl)-1-propanethiol coated Fe3O4 nanoparticles.  

PubMed

Extraction, pre-concentration, and determination of trace amounts of silver, cadmium, copper, mercury, and lead from some food samples were investigated by magnetic solid phase extraction using Fe3O4 nanoparticles coated with 3-(trimethoxysilyl)-1-propanethiol and modified with ethylene glycol bis-mercaptoacetate as a new adsorbent. SEM, X-ray diffraction, and FT-IR were used to characterise the adsorbent. Metal ions were measured using ICP-OES, except for mercury, which was determined by CV-AAS method. Various factors affecting the extraction and desorption of target metal ions were investigated. 1 mL of 1 mol/L HCl and 5% thiourea was used as eluent. The detection limits of 0.07, 0.06, 0.09, 0.01, and 0.08 ng/mL were obtained for silver, cadmium, copper, mercury, and lead with enrichment factors of 240, 294, 297, 291, and 236, respectively. The method was used for determination of target metal ions in rice, canned tuna fish, and tea leaves. PMID:24423536

Mashhadizadeh, Mohammad Hossein; Amoli-Diva, Mitra; Shapouri, Mahmoud Reza; Afruzi, Hossein

2014-05-15

333

Acute and subacute response of iron, zinc, copper and selenium in pigs experimentally infected with Actinobacillus pleuropneumoniae.  

PubMed

This study was performed to characterise the response of iron (Fe), zinc (Zn), copper (Cu) and selenium (Se) in bacterial-induced porcine acute phase reaction (APR). Twenty piglets were challenged by aerosolic infection with Actinobacillus pleuropneumoniae (A.pp.) serotype 2, ten piglets serving as controls. Blood sampling was done initially and at day 4 and 21 after infection, collection of liver tissue was done at day 21 (autopsy). A.pp.-infection caused fever and respiratory symptoms. APR at day 4 after infection was marked by an increase in total white blood cells, granulocytes and monocytes in whole blood samples and an increase in globulin/albumin ratio (G/A), ?2-globulins, C-reactive protein, haptoglobin, ceruloplasmin (Cp), Cu and Se in serum. Concurrently, there was a decrease in haemoglobin (Hb) and packed cell volume (PCV) in whole blood as well as a decrease in albumin, transferrin, total iron binding capacity and Fe in serum and Zn in plasma. The subacute stage at day 21 was characterised by progressively increased concentrations of G/A, ?-globulins and ?-globulins reflecting the specific immune reaction. Hb and PCV showed further decreases, all other parameters returned to the initial concentrations. Glutathione peroxidase activity in plasma and liver tissue remained unaffected by A.pp.-infection. The liver concentration (day 21) of Zn was found to be higher, that of Se was lower in the A.pp.-group, whereas hepatic concentrations of Cu and Fe were not affected by A.pp.-infection. In summary, the acute and subacute stages of A.pp.-infection were accurately characterised by the APR-related parameters. Se was only marginally affected by the A.pp.-infection. The elevated plasma Cu concentration may be a side effect of the transient hepatic induction of Cp synthesis. Zn responded, being distinctly reduced in plasma and probably having been sequestered in the liver tissue. Reduction in serum Fe can be regarded as an unspecific defence mechanism in A.pp.-infection to withdraw Fe from bacterial acquisition systems. PMID:25100437

Humann-Ziehank, Esther; Menzel, Anne; Roehrig, Petra; Schwert, Barbara; Ganter, Martin; Hennig-Pauka, Isabel

2014-10-01

334

Origin of fluids in iron oxide-copper-gold deposits: constraints from ? 37Cl, 87Sr/86Sri and Cl/Br  

NASA Astrophysics Data System (ADS)

The origin of the hypersaline fluids (magmatic or basinal brine?), associated with iron oxide (Cu-U-Au-REE) deposits, is controversial. We report the first chlorine and strontium isotope data combined with Cl/Br ratios of fluid inclusions from selected iron oxide-copper-gold (IOCG) deposits (Candelaria, Raúl-Condestable, Sossego), a deposit considered to represent a magmatic end member of the IOCG class of deposit (Gameleira), and a magnetite-apatite deposit (El Romeral) from South America. Our data indicate mixing of a high ? 37Cl magmatic fluid with near 0‰ ? 37Cl basinal brines in the Candelaria, Raúl-Condestable, and Sossego IOCG deposits and leaching of a few weight percent of evaporites by magmatic-hydrothermal (?) fluids at Gameleira and El Romeral. The Sr isotopic composition of the inclusion fluids of Candelaria, Raúl-Condestable, and El Romeral confirms the presence of a non-magmatic fluid component in these deposits. The heavy chlorine isotope signatures of fluids from the IOCG deposits (Candelaria, Raúl-Condestable, Sossego), reflecting the magmatic-hydrothermal component of these fluids, contrast with the near 0‰ ? 37Cl values of porphyry copper fluids known from the literature. The heavy chlorine isotope compositions of fluids of the investigated IOCG deposits may indicate a prevailing mantle Cl component in contrast to porphyry copper fluids, an argument also supported by Os isotopes, or could result from differential Cl isotope fractionation processes (e.g. phase separation) in fluids of IOCG and porphyry Cu deposits.

Chiaradia, Massimo; Banks, Dave; Cliff, Robert; Marschik, Robert; de Haller, Antoine

2006-09-01

335

Fractionation of Fulvic Acid by Iron and Aluminum Oxides-Influence on Copper Toxicity to Ceriodaphnia dubia.  

PubMed

This study examines the effect on aquatic copper toxicity of the chemical fractionation of fulvic acid (FA) that results from its association with iron and aluminum oxyhydroxide precipitates. Fractionated and unfractionated FAs obtained from streamwater and suspended sediment were utilized in acute Cu toxicity tests on Ceriodaphnia dubia. Toxicity test results with equal FA concentrations (6 mg FA/L) show that the fractionated dissolved FA was 3 times less effective at reducing Cu toxicity (EC50 13 ± 0.6 ?g Cu/L) than were the unfractionated dissolved FAs (EC50 39 ± 0.4 and 41 ± 1.2 ?g Cu/L). The fractionation is a consequence of preferential sorption of molecules having strong metal-binding (more aromatic) moieties to precipitating Fe- and Al-rich oxyhydroxides, causing the remaining dissolved FA to be depleted in these functional groups. As a result, there is more bioavailable dissolved Cu in the water and hence greater potential for Cu toxicity to aquatic organisms. In predicting Cu toxicity, biotic ligand models (BLMs) take into account dissolved organic carbon (DOC) concentration; however, unless DOC characteristics are accounted for, model predictions can underestimate acute Cu toxicity for water containing fractionated dissolved FA. This may have implications for water-quality criteria in systems containing Fe- and Al-rich sediment, and in mined and mineralized areas in particular. Optical measurements, such as specific ultraviolet absorbance at 254 nm (SUVA254), show promise for use as spectral indicators of DOC chemical fractionation and inferred increased Cu toxicity. PMID:25289694

Smith, Kathleen S; Ranville, James F; Lesher, Emily K; Diedrich, Daniel J; McKnight, Diane M; Sofield, Ruth M

2014-10-21

336

Iron and copper isotope fractionation during filtration and ultrafiltration of boreal organic-rich waters  

NASA Astrophysics Data System (ADS)

Typical feature of all boreal surface waters is high concentration of dissolved (< 0.22 µm) organic matter (DOM) and iron, notably in the form of Fe(III)-OM complexes. Organic and organo-mineral colloids are the most likely carriers of trace metals such as Cu in rivers of the boreal zone. This work addresses colloidal speciation of Cu and Fe using conventional size separation technique, on-site frontal ultrafiltration. Specifically, we aimed to test the possibility of the presence of different pools of metal having specific isotopic signatures in different colloidal fractions using stable isotope measurements. We have chosen Cu for its high affinity to colloidal DOM and Fe for its tendency to form stable organo-mineral colloids of various size. Samples of natural waters were collected from small rivers, lakes, bogs, groundwater and soil environments in the Northern Karelia (NW Russia) during summer baseflow period. Large volumes (20-40 L) of water were filtered in the field through progressively decreasing pore size filters: 20, 10, 5, 0.8, 0.45, 0.22, 0.1 µm and 100, 10 and 1 kDa (1 kDa ~ 1 nm) using nylon and regenerated cellulose membranes and frontal ultrafiltration (Millipore, Amicon) devises. The homogeneity of the sample was verified by tracing radiogenic Sr isotopes in each fraction. In all filtrates and ultrafiltrates (permeates), and in selected retentates, stable isotopic composition of Cu and Fe was measured using double focusing high resolution MC-ICP MS (Neptune). We observe rather constant Cu isotopic ratio in all filtrate series and a systematic enrichment of heavy isotope of Fe with decreasing poresize. These preliminary results can be explained by strong complexation of Cu with small-size organic ligands of fulvic nature and its partial association with organo-mineral colloids. Both Fe(III) - OM complxeation and Fe(III) oxyhydroxides precipitation can be invoked to explain Fe isotope fractionation. This work allows, for the first, time, multi-isotopic approach to trace the origin of colloids in surficial waters and it provides new constrains on chemical speciation (and, thus, bioavailability) of metals in colloids of various size. The work is executed at a Russian Federal Property Fund and CNRS support (?? 08-05-00312_a, 07-05-92212-CNRS_a).

Ilina, Svetlana M.; Viers, Jerome; Pokrovsky, Oleg S.; Poitrasson, Franck; Lapitsky, Sergey A.; Alekhin, Yuriy V.

2010-05-01

337

Mineral commodity profiles: Cadmium  

USGS Publications Warehouse

Overview -- Cadmium is a soft, low-melting-point metal that has many uses. It is similar in abundance to antimony and bismuth and is the 63d element in order of crustal abundance. Cadmium is associated in nature with zinc (and, less closely, with lead and copper) and is extracted mainly as a byproduct of the mining and processing of zinc. In 2000, it was refined in 27 countries, of which the 8 largest accounted for two-thirds of world production. The United States was the third largest refiner after Japan and China. World production in 2000 was 19,700 metric tons (t) and U.S. production was 1,890 t. In the United States, one company in Illinois and another in Tennessee refined primary cadmium. A Pennsylvania company recovered cadmium from scrap, mainly spent nickel-cadmium (NiCd) batteries. The supply of cadmium in the world and in the United States appears to be adequate to meet future industrial needs; the United States has about 23 percent of the world reserve base.

Butterman, W. C.; Plachy, Jozef

2004-01-01

338

Cadmium transport in isolated enterocytes of freshwater rainbow trout: interactions with zinc and iron, effects of complexation with cysteine, and an ATPase-coupled efflux.  

PubMed

The present study investigated the mechanisms of intestinal cadmium (Cd) uptake and efflux, using isolated enterocytes of freshwater rainbow trout (Oncorhynchus mykiss) as the experimental model. The apical uptake of free Cd(2+) in the enterocytes was a saturable and high-affinity transport process. Both zinc (Zn(2+)) and iron (Fe(2+)) inhibited cellular Cd(2+) uptake through a competitive interaction, suggesting that Cd(2+) enters enterocytes via both Zn(2+) (e.g., ZIP8) and Fe(2+) (e.g., DMT1) transport pathways. Cellular Cd(2+) uptake increased in the presence of HCO(3)(-), which resembled the function of mammalian ZIP8. Cellular Cd(2+) uptake was unaffected by Ca(2+), indicating that Cd(2+) does not compete with Ca(2+) for apical uptake. Interestingly, Cd uptake was influenced by the presence of l-cysteine, and under the exposure condition where Cd(Cys)(+) was the predominant Cd species, cellular Cd uptake rate increased with the increased concentration of Cd(Cys)(+). The kinetic analysis indicated that the uptake of Cd(Cys)(+) occurs through a low capacity transport mechanism relative to that of free Cd(2+). In addition, Cd efflux from the enterocytes decreased in the presence of an ATPase inhibitor (orthovanadate), suggesting the existence of an ATPase-coupled extrusion process. Overall, our findings provide new mechanistic insights into the intestinal Cd transport in freshwater fish. PMID:21930242

Kwong, Raymond W M; Niyogi, Som

2012-03-01

339

Effects of chloride, sulfate and natural organic matter (NOM) on the accumulation and release of trace-level inorganic contaminants from corroding iron.  

PubMed

This study examined effects of varying levels of anions (chloride and sulfate) and natural organic matter (NOM) on iron release from and accumulation of inorganic contaminants in corrosion scales formed on iron coupons exposed to drinking water. Changes of concentrations of sulfate and chloride were observed to affect iron release and, in lesser extent, the retention of representative inorganic contaminants (vanadium, chromium, nickel, copper, zinc, arsenic, cadmium, lead and uranium); but, effects of NOM were more pronounced. DOC concentration of 1 mg/L caused iron release to increase, with average soluble and total iron concentrations being four and two times, respectively, higher than those in the absence of NOM. In the presence of NOM, the retention of inorganic contaminants by corrosion scales was reduced. This was especially prominent for lead, vanadium, chromium and copper whose retention by the scales decreased from >80% in the absence of NOM to <30% in its presence. Some of the contaminants, notably copper, chromium, zinc and nickel retained on the surface of iron coupons in the presence of DOC largely retained their mobility and were released readily when ambient water chemistry changed. Vanadium, arsenic, cadmium, lead and uranium retained by the scales were largely unsusceptible to changes of NOM and chloride levels. Modeling indicated that the observed effects were associated with the formation of metal-NOM complexes and effects of NOM on the sorption of the inorganic contaminants on solid phases that are typical for iron corrosion in drinking water. PMID:23863395

Peng, Ching-Yu; Ferguson, John F; Korshin, Gregory V

2013-09-15

340

Effects of silicon, copper and iron on static and dynamic properties of alloy 206 (aluminum-copper) in semi-solids produced by the SEED process  

NASA Astrophysics Data System (ADS)

The advantages of producing metal parts by rheocasting are generally recognised for common foundry alloys of Al-Si. However, other more performing alloys in terms of mechanical properties could have a great interest in specialized applications in the automotive industry, while remaining competitive in the forming. Indeed, the growing demand for more competitive products requires the development of new alloys better suited to semi-solid processes. Among others, Al-Cu alloys of the 2XX series are known for their superior mechanical strength. However, in the past, 2XX alloys were never candidates for pressure die casting. The main reason is their propensity to hot tearing. Semi-solid processes provide better conditions for molding with the rheological behavior of dough and molding temperatures lower reducing this type of defect. In the initial phase, this research has studied factors that reduce hot tearing susceptibility of castings produced by semi-solid SEED of alloy 206. Subsequently, a comparative study on the tensile properties and fatigue was performed on four variants of the alloy 206. The results of tensile strength and fatigue were compared with the specifications for applications in the automotive industry and also to other competing processes and alloys. During this study, several metallurgical aspects were analyzed. The following main points have been validated: i) the main effects of compositional variations of silicon, iron and copper alloy Al-Cu (206) on the mechanical properties, and ii) certain relationships between the mechanism of hot cracking and the solidification rate in semi-solid. Parts produced from the semi-solid paste coming from the SEED process combined with modified 206 alloys have been successfully molded and achieved superior mechanical properties than the requirements of the automotive industry. The fatigue properties of the two best modified 206 alloys were higher than those of A357 alloy castings and are close to those of the wrought alloy AA6061. At present, there is simply no known application for pressure die-cast alloy with 206 (Liquid Die-casting). This is mainly due to the high propensity to hot cracking and limitations facing the part geometry and the subsequent assembly. This study demonstrated that in addition to pieces produced by semi-solid die-casting using large variations in chemical composition, the SEED process allows obtaining spare sound (sound part) and more complex geometry. Moreover, as the semi-solid parts have less porosity, they can also be machined and welded for some applications. The conclusions of this study demonstrate significant progress in identifying the main issues related to the feasibility of die-casting good parts with high performance using the modified 206 alloy combined with SEED process. This work is therefore a baseline work in the development of new Al-Cu alloys for industries of semi-solid and, at the same time, for the expansion of aluminum for high performance applications in the industry. N.B. This thesis is part of a research project developed by the NSERC / Rio Tinto Akan Industrial Research Chair in Metallurgy of Innovative Aluminum Transformation (CIMTAL).

Lemieux, Alain

341

Inhibition of cadmium-induced hypertension in rats.  

PubMed

In a low cadmium environment, adding 10 parts per million (ppm) of cadmium to the drinking water of rats for 3 to 18 months induced increases in systolic pressure averaging 12 to 18 mm Hg. The pressor effect of the cadmium was inhibited by adding 3.6 ppm of selenium or 200 ppm of zinc to the drinking water or by dissolving the cadmium in hard water rather than deionized water. A second experiment with 2.5 ppm of cadmium and smaller amounts of selenium and zinc was confirmatory. Exposure to 10 ppm of cadmium increased renal, hepatic, and cardiac cadmium many fold from barely detectable control levels; however, the increases were much less when the cadmium was dissolved in hard water. Cadmium exposure also increased tissue zinc by 30 to 60%. The addition of selenium to cadmium further increased cardiac cadmium, but the addition of zinc to cadmium had no further effect on tissue cadmium. Tissue selenium concentrations were suggestively but not significantly higher following selenium exposure. Cadmium alone, or combined with selenium or zinc, increased renal copper; while the combination of cadmium and selenium increased hepatic copper. PMID:7367855

Perry, H M; Erlanger, M W; Blotcky, A J; Perry, E F

1980-03-01

342

Chelatometric determination of calcium and magnesium in iron ores, slags, anorthosite, limestone, copper-nickel-lead-zinc ores and divers materials.  

PubMed

Chelatometric methods for the determination of calcium and magnesium in iron ores, slags, anorthosite, copper-nickel-lead-zinc ores and various other materials are described. Potential interfering elements are masked with triethanolamine and potassium cyanide. In one aliquot calcium is titrated at pH > 12, with calcein and thymolphthalein mixed indicator and in another aliquot calcium and magnesium are titrated in ammonia buffer, with o-cresolphthalein complexone screened with Naphthol Green B as indicator. The results compare favourably with certified values for reference materials of diverse nature. PMID:18962661

Hitchen, A; Zechanowitsch, G

1980-03-01

343

Hydrothermal alteration, fluid inclusions and stable isotope systematics of the Alvo 118 iron oxide–copper–gold deposit, Carajás Mineral Province (Brazil): Implications for ore genesis  

Microsoft Academic Search

The Alvo 118 iron oxide–copper–gold (IOCG) deposit (170 Mt at 1.0 wt.% Cu, 0.3 g\\/t Au) lies in the southern sector of the\\u000a Itacaúnas Shear Belt, Carajás Mineral Province, along a WNW–ESE-striking, 60-km-long shear zone, close to the contact of the\\u000a ~2.76-Ga metavolcano-sedimentary Itacaiúnas Supergroup and the basement (~3.0 Ga Xingu Complex). The Alvo 118 deposit is hosted\\u000a by mafic and felsic metavolcanic

Ignacio Torresi; Roberto Perez Xavier; Diego F. A. Bortholoto; Lena V. S. Monteiro

344

Spatial and temporal zoning of hydrothermal alteration and mineralization in the Sossego iron oxide–copper–gold deposit, Carajás Mineral Province, Brazil: paragenesis and stable isotope constraints  

Microsoft Academic Search

The Sossego iron oxide–copper–gold deposit (245 Mt @ 1.1% Cu, 0.28 g\\/t Au) in the Carajás Mineral Province of Brazil consists\\u000a of two major groups of orebodies (Pista–Sequeirinho–Baiano and Sossego–Curral) with distinct alteration assemblages that are\\u000a separated from each other by a major high angle fault. The deposit is located along a regional WNW–ESE-striking shear zone\\u000a that defines the contact between

Lena V. S. Monteiro; Roberto P. Xavier; Emerson R. de Carvalho; Murray W. Hitzman; Craig A. Johnson; Carlos Roberto de Souza Filho; Ignácio Torresi

2008-01-01

345

An intrusion-related origin for Cu-Au mineralization in iron oxide-copper-gold (IOCG) provinces  

NASA Astrophysics Data System (ADS)

Major Cu-Au deposits of iron oxide-copper-gold (IOCG) style are temporally associated with oxidized, potassic granitoids similar to those linked to major porphyry Cu-Au deposits. Stable and radiogenic isotope evidence indicates fluids and ore components were likely sourced from the intrusions. IOCG deposits form over a range of crustal levels because CO2-rich fluids separate from the magmas at higher pressures than in CO2-poor systems, thereby, promoting partitioning of H2O, Cl and metals to the fluid phase. At deep levels, the magma-fluid system cannot generate sufficient mechanical energy to fracture the host rocks as in porphyry systems and the IOCG deposits therefore form in a variety of fault-related structural traps where the magmatic fluids may mix with other fluids to promote ore formation. At shallow levels, the IOCG deposits form breccia and fracture-hosted mineralization styles similar to the hydrothermal intrusive breccias and sulphide vein systems that characterize many porphyry Cu-Au deposits. The fluids associated with IOCG deposits are typically H2O-CO2-salt fluids that evolve by unmixing of the carbonic phase and by mixing with fluids from other sources. In contrast, fluids in porphyry systems typically evolve by boiling of moderate salinity fluid to produce high salinity brine and a vapor phase commonly with input of externally derived fluids. These different fluid compositions and mechanisms of evolution lead to different alteration types and parageneses in porphyry and IOCG deposits. Porphyry Cu-Au deposits typically evolve through potassic, sericitic and (intermediate and/or advanced) argillic stages, while IOCG deposits typically evolve through sodic(-calcic), potassic and carbonate-rich stages, and at deeper levels, generally lack sericitic and argillic alteration. The common association of porphyry and IOCG Cu-Au deposits with potassic, oxidized intermediate to felsic granitoids, together with their contrasting fluid compositions, alteration styles and parageneses suggest that they should be considered as part of the broad family of intrusion-related systems but that they are typically not directly related to each other.

Pollard, Peter J.

2006-05-01

346

Investigation of the effects of cadmium by micro analytical methods on Lycopersicon esculentum Mill. roots.  

PubMed

The interactions between cadmium stress and plant nutritional elements have been investigated on complete plant or at the level of organs. This study was undertaken to contribute to the exploration of the physiological basis of cadmium phytotoxicity. We examined the changes in the nutritional element compositions of the root epidermal cells of the seedlings of Lycopersicon esculentum Mill. at the initial growth stages that is known as the most sensitive stage to the stress. Effects of cadmium stress on the seedlings of Lycopersicon esculentum Mill. were examined by EDX (Energy Dispersive X-Ray Microanalysis) assay performed with using low vacuum (? 24 Pascal) Scanning Electron Microscopy. In the analysis performed at the level of root epidermal cells, some of the macro- and micronutrient contents of the cells (carbon, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, copper, and zinc levels) were found to change when the applying toxic concentrations of cadmium. There was no change in the manganese and sodium content of the epidermal cells. It was concluded that the changes in nutritional element composition of the cells can be considered as an effective parameter in explaining the physiological mechanisms of cadmium-induced growth inhibition. PMID:25194735

Colak, G; Baykul, M C; Gürler, R; Catak, E; Caner, N

2014-09-01

347

Activation of Methanogenesis by Cadmium in the Marine Archaeon Methanosarcina acetivorans  

PubMed Central

Methanosarcina acetivorans was cultured in the presence of CdCl2 to determine the metal effect on cell growth and biogas production. With methanol as substrate, cell growth and methane synthesis were not altered by cadmium, whereas with acetate, cadmium slightly increased both, growth and methane rate synthesis. In cultures metabolically active, incubations for short-term (minutes) with 10 µM total cadmium increased the methanogenesis rate by 6 and 9 folds in methanol- and acetate-grown cells, respectively. Cobalt and zinc but not copper or iron also activated the methane production rate. Methanogenic carbonic anhydrase and acetate kinase were directly activated by cadmium. Indeed, cells cultured in 100 µM total cadmium removed 41–69% of the heavy metal from the culture and accumulated 231–539 nmol Cd/mg cell protein. This is the first report showing that (i) Cd2+ has an activating effect on methanogenesis, a biotechnological relevant process in the bio-fuels field; and (ii) a methanogenic archaea is able to remove a heavy metal from aquatic environments. PMID:23152802

Lira-Silva, Elizabeth; Santiago-Martinez, M. Geovanni; Hernandez-Juarez, Viridiana; Garcia-Contreras, Rodolfo; Moreno-Sanchez, Rafael; Jasso-Chavez, Ricardo

2012-01-01

348

Characterization of iron- and sulphide mineral-oxidizing moderately thermophilic acidophilic bacteria from an Indonesian auto-heating copper mine waste heap and a deep South African gold mine  

Microsoft Academic Search

Iron- and chalcopyrite-oxidizing enrichment cultures were obtained at 50°C from acidic, high-temperature, copper\\/gold mine environments in Indonesia and South Africa. Over 90% copper yield was obtained from chalcopyrite concentrate with the Indonesian enrichment in 3 months with 2% solids concentration, when pH was maintained at around 2. Neither addition of silver cations nor an enhanced nutrient concentration influenced chalcopyrite leaching. Excision

Päivi H.-M. Kinnunen; Jaakko A. Puhakka

2004-01-01

349

Syntheses and structural characterization of iron(II) and copper(II) coordination compounds with the neutral flexible bidentate N-donor ligands  

NASA Astrophysics Data System (ADS)

Two new coordination compounds [Fe(bib)2(N3)2]n(1) and [Cu2(bpp)2(N3)4] (2) with azide and flexible ligands 1,4-bis(imidazolyl)butane (bib) and 1,3-bis(3,5-dimethylpyrazolyl)propane (bpp) were prepared and structurally characterized. In the 2D network structure of 1, the iron(II) ion lies on an inversion center and exhibits an FeN6 octahedral arrangement while in the dinuclear structure of 2, the copper(II) ion adopts an FeN5 distorted square pyramid geometry. In the complex 1, each ?2-bib acts as bridging ligand connecting two adjacent iron(II) ions while in the complex 2, the bpp ligand is coordinated to copper(II) ion in a cyclic-bidentate fashion forming an eight-membered metallocyclic ring. Coordination compounds 1 and 2 have been characterized by infrared spectroscopy, elemental analyses and single-crystal X-ray diffraction. Thermal analysis of polymer 1 was also studied.

Beheshti, Azizolla; Lalegani, Arash; Bruno, Giuseppe; Rudbari, Hadi Amiri

2014-08-01

350

Acute toxicity of copper, lead, cadmium, and zinc to early life stages of white sturgeon (Acipenser transmontanus) in laboratory and Columbia River water.  

PubMed

Populations of white sturgeon (Acipenser transmontanus) are in decline in North America. This is attributed, primarily, to poor recruitment, and white sturgeon are listed as threatened or endangered in several parts of British Columbia, Canada, and the United States. In the Columbia River, effects of metals have been hypothesized as possible contributing factors. Previous work has demonstrated that early life stage white sturgeon are particularly sensitive to certain metals, and concerns over the level of protectiveness of water quality standards are justified. Here we report results from acute (96-h) toxicity tests for copper (Cu), cadmium (Cd), zinc (Zn), and lead (Pb) from parallel studies that were conducted in laboratory water and in the field with Columbia River water. Water effect ratios (WERs) and sensitivity parameters (i.e., median lethal accumulations, or LA50s) were calculated to assess relative bioavailability of these metals in Columbia River water compared to laboratory water, and to elucidate possible differences in sensitivity of early life stage white sturgeon to the same concentrations of metals when tested in the different water sources. For Cu and Pb, white sturgeon toxicity tests were initiated at two life stages, 8 and 40 days post-hatch (dph), and median lethal concentrations (LC50s) ranged between 9-25 ?g Cu/L and 177-1,556 ?g Pb/L. LC50s for 8 dph white sturgeon exposed to Cd in laboratory water and river water were 14.5 and 72 ?g/L, respectively. Exposure of 8 dph white sturgeon to Zn in laboratory and river water resulted in LC50s of 150 and 625 ?g/L, respectively. Threshold concentrations were consistently less in laboratory water compared with river water, and as a result, WERs were greater than 1 in all cases. In addition, LA50s were consistently greater in river water exposures compared with laboratory exposures in all paired tests. These results, in combination with results from the biotic ligand model, suggest that the observed differences in toxicity between river water exposures and laboratory water exposures were not entirely due to differences in water quality and metal bioavailability but rather in combination with differences in fish sensitivity. It is hypothesized that differences in concentrations of calcium in the different water sources might have resulted in differences in acquired sensitivity of sturgeon to metals. Canadian water quality guidelines, US national criteria for the protection of aquatic life, and water quality criteria for the state of Washington were less than LC50 values for all metals and life stages tested in laboratory and Columbia River water. With the exception, however, that 40 dph white sturgeon exposed to Cu in laboratory water resulted in threshold values that bordered US national criteria and criteria for the state of Washington. PMID:24920427

Vardy, David W; Santore, Robert; Ryan, Adam; Giesy, John P; Hecker, Markus

2014-07-01

351

Experimental studies of the interaction of aqueous metal cations with mineral substrates: Lead, cadmium, and copper with perthitic feldspar, muscovite, and biotite  

NASA Astrophysics Data System (ADS)

The interactions between each of the metal ions copper(II), cadmium(II), and lead(II) in aqueous solution and the surfaces of the minerals muscovite, biotite, and perthitic feldspar have been studied using batch sorption experiments and X-ray photoelectron (XPS) and X-ray absorption (XAS) spectroscopies. The purpose of the work has been to establish the extent of removal from solution of these metal ions by interaction with the mineral surfaces and the mechanisms involved (whether ion exchange, precipitation, or adsorption). The experiments utilised both powdered samples and flat polished or cleaved surfaces of natural minerals which were characterised compositionally and structurally by electron probe microanalysis and X-ray diffraction. Reaction solutions contained Cu (II) , Cd (II) , or Pb (II) in a background electrolyte of NaNO 3 (0.1 or 0.01 M) at a pH of 5.4 ± 0.2 with a wide range of initial concentrations. The extent of uptake of each of the metals by a particular mineral substrate was measured by analysis of the liquid portion separated by centrifugation after a controlled period of exposure (solution analyses were performed by atomic absorption spectroscopy or by inductively coupled plasma mass spectroscopy as appropriate). The data obtained were used to plot sorption isotherms for the various metal ions and substrates showing the dependence of uptake on initial concentration of metal in solution and background electrolyte concentration. Studies of the reacted mineral surfaces using XPS were used to identify the chemical speciation and bonding environment of Cu, Cd, and Pb present at the surface and to assess surface coverage in planar surface samples and whether significant infiltration of the metal cation into the mineral surface had occurred. Parallel studies using XAS (in particular Extended X-ray Absorption Fine Structure Spectroscopy-EXAFS) were employed to determine the local environments of Cu, Cd, and Pb at the surface of powdered mineral samples. Planar surfaces of muscovite, biotite, and perthitic feldspar exposed to Cu(II) and of muscovite exposed to Cd(II) were also studied using Reflection Extended X-ray Absorption Fine Structure (REFLEXAFS) spectroscopy. The results show that muscovite, biotite, and perthitic feldspar have surfaces that can strongly interact with (and remove) particularly Cu (II) and Pb (II) in such mildly acidic aqueous solutions. Biotite also strongly interacts with Cd(II) in solution. Generally biotite provides the most reactive mineral surface followed by muscovite, with perthitic feldspar being the least reactive. Of the possible mechanisms for removal of metals under the conditions of these experiments, precipitation was not observed, but three other mechanisms (inner-sphere complexation, outer-sphere complexation, and ion exchange) were all observed. The inner-sphere complexation and ion exchange mechanisms often take place in combination: however, Pb (II) forms no outer-sphere complexes on the surfaces of these minerals, and Cd (II) forms only outer-sphere complexes with perthitic feldspar and muscovite. Cu(II) in solution promotes the release of K + from the surface region of muscovite and, particularly, biotite, and subsequent uptake of Cu (II) by ion exchange. These findings have important environmental implications and show the significant role that major rock-forming aluminosilicates may play in the geochemical cycling of Cu(II), Cd(II), and Pb(II).

Farquhar, Morag L.; Vaughan, David J.; Hughes, Colin R.; Charnock, John M.; England, Katharine E. R.

1997-08-01

352

Effects of microbial iron reduction and oxidation on the immobilization and mobilization of copper in synthesized Fe(III) minerals and Fe-rich soils.  

PubMed

The effects of microbial iron reduction and oxidation on the immobilization and mobilization of copper were investigated in a high concentration of sulfate with synthesized Fe(III) minerals and red earth soils rich in amorphous Fe (hydr)oxides. Batch microcosm experiments showed that red earth soil inoculated with subsurface sediments had a faster Fe(III) bioreduction rate than pure amorphous Fe(III) minerals and resulted in quicker immobilization of Cu in the aqueous fraction. Coinciding with the decrease of aqueous Cu, SO4(2-) in the inoculated red earth soil decreased acutely after incubation. The shift in the microbial community composite in the inoculated soil was analyzed through denaturing gradient gel electrophoresis. Results revealed the potential cooperative effect of microbial Fe(III) reduction and sulfate reduction on copper immobilization. After exposure to air for 144 h, more than 50% of the immobilized Cu was remobilized from the anaerobic matrices; aqueous sulfate increased significantly. Sequential extraction analysis demonstrated that the organic matter/sulfide-bound Cu increased by 52% after anaerobic incubation relative to the abiotic treatment but decreased by 32% after oxidation, indicating the generation and oxidation of Cu-sulfide coprecipitates in the inoculated red earth soil. These findings suggest that the immobilization of copper could be enhanced by mediating microbial Fe(III) reduction with sulfate reduction under anaerobic conditions. The findings have an important implication for bioremediation in Cucontaminated and Fe-rich soils, especially in acid-mine-drainage-affected sites. PMID:24448165

Hu, Chaohua; Zhang, Youchi; Zhang, Lei; Luo, Wensui

2014-04-01

353

Theoretical (in B3LYP/6-3111++G** level), spectroscopic (FT-IR, FT-Raman) and thermogravimetric studies of gentisic acid and sodium, copper(II) and cadmium(II) gentisates  

NASA Astrophysics Data System (ADS)

The DFT calculations (B3LYP method with 6-311++G(d,p) mixed with LanL2DZ for transition metals basis sets) for different conformers of 2,5-dihydroxybenzoic acid (gentisic acid), sodium 2,5-dihydroxybenzoate (gentisate) and copper(II) and cadmium(II) gentisates were done. The proposed hydrated structures of transition metal complexes were based on the results of experimental findings. The theoretical geometrical parameters and atomic charge distribution were discussed. Moreover Na, Cu(II) and Cd(II) gentisates were synthesized and the composition of obtained compounds was revealed by means of elemental and thermogravimetric analyses. The FT-IR and FT-Raman spectra of gentisic acid and gentisates were registered and the effect of metals on the electronic charge distribution of ligand was discussed.

Regulska, E.; Kalinowska, M.; Wojtulewski, S.; Korczak, A.; Sienkiewicz-Gromiuk, J.; Rz?czy?ska, Z.; ?wis?ocka, R.; Lewandowski, W.

2014-11-01

354

Effect of chronic ethanol ingestion on the metabolism of copper, iron, manganese, selenium, and zinc in an animal model of alcoholic cardiomyopathy  

SciTech Connect

Alcoholic cardiomyopathy (AC) is one of the diseases caused by alcohol abuse, and there has been considerable debate about the possibility that nutritional factors may be important in the etiology of AC. In addition, there is evidence that ethanol may affect the metabolism of trace elements. The purpose of this investigation was to determine if chronic ethanol administration produces changes in the metabolism of the essential metals copper, iron, manganese, zinc, and selenium using an animal model of AC. Eighteen male Sprague-Dawley rats were divided into three groups; an ad libitum control group (AL), a pair-fed control group (PF), and an ethanol-dosed group (ETOH). The latter group received gradually increasing concentrations (5-25%) of ethanol in the drinking water for 15 wk. Food intake was monitored and urine and feces collected for a 4-d period during the study to determine ethanol effects on trace-element balance. Growth of both the PF and ETOH animals was inhibited. Ethanol produced substantial increases in liver manganese and decreases in liver copper and zinc. Metal concentrations in heart and concentrations in other tissues studied (spleen, testes, brain, bone, kidney, and muscle) did not differ significantly among the groups, except for testes selenium and kidney zinc. Reduced food intake and ethanol ingestion were associated with a reduced percentage of ingested selenium excreted in the urine. Deficiencies of copper, iron, manganese, selenium, and zinc in myocardial tissue are not likely to be involved in the pathogenesis of AC in the rat. 38 references, 1 figure, 4 tables.

Bogden, J.D.; Al-Rabiai, S.; Gilani, S.H.

1984-01-01

355

Influence of aluminum, silicon, and copper on the properties of composite welded joints in an iron base  

Microsoft Academic Search

The properties of welded steel-aluminum joints is governed to a considerable extent by the type of plating preliminarily applied to the steel and the dimensions and character of the diffusion layer produced at the boundary between the iron and molten aluminum [1]. The present investigation completed our study of the influence of alloying Of the iron base on the properties

V. R. Ryabov; V. I. Yumatova

1975-01-01

356

Ecological risk assessment of on-site soil washing with iron(III) chloride in cadmium-contaminated paddy field.  

PubMed

On-site soil washing with iron(III) chloride reduces Cd levels in soil, and thus the human health risks caused by Cd in food. However, it may threaten aquatic organisms when soil washing effluent is discharged to open aquatic systems. Therefore, we conducted trial-scale on-site soil washing and ecological risk assessment in Nagano and Niigata prefectures, Japan. The ecological effect of effluent water was investigated by two methods. The first was bioassay using standard aquatic test organisms. Twice-diluted effluent water from the Nagano site and the original effluent water from the Niigata site had no significant effects on green algae, water flea, caddisfly, and fish. The safe dilution rates were estimated as 20 times and 10 times for the Nagano and Niigata sites, respectively, considering an assessment factor of 10. The second method was probabilistic effect analysis using chemical analysis and the species sensitivity distribution concept. The mixture effects of CaCl(2), Al, Zn, and Mn were considered by applying a response additive model. The safe dilution rates, assessed for a potentially affected fraction of species of 5%, were 7.1 times and 23.6 times for the Nagano and Niigata sites, respectively. The actual dilution rates of effluent water by river water at the Nagano and Niigata sites were 2200-67,000 times and 1300-110,000 times, respectively. These are much larger than the safe dilution rates derived from the two approaches. Consequently, the ecological risk to aquatic organisms of soil washing is evaluated as being below the concern level. PMID:22377402

Nagai, Takashi; Horio, Takeshi; Yokoyama, Atsushi; Kamiya, Takashi; Takano, Hiroyuki; Makino, Tomoyuki

2012-06-01

357

Long-distance transport, vacuolar sequestration and transcriptional responses induced by cadmium and arsenic  

PubMed Central

Summary Iron, zinc, copper and manganese are essential metals for cellular enzyme functions while cadmium, mercury and the metalloid arsenic lack any biological function. Both, essential and non-essential metals and metalloids are extremely reactive and toxic. Therefore, plants have acquired specialized mechanisms to sense, transport and maintain essential metals within physiological concentrations and to detoxify non-essential metals and metalloids. This review focuses on the recent identification of transporters that sequester cadmium and arsenic in vacuoles and the mechanisms mediating the partitioning of these metal(loid)s between roots and shoots. We further discuss recent models of phloem-mediated long-distance transport, seed accumulation of Cd and As and recent data demonstrating that plants posses a defined transcriptional response that allow plants to preserve metal homeostasis. This research is instrumental for future engineering of reduced toxic metal(loid) accumulation in edible crop tissues as well as for improved phytoremediation technologies. PMID:21820943

Mendoza-Cózatl, David G.; Jobe, Timothy O.; Hauser, Felix; Schroeder, Julian I.

2011-01-01

358

Nutritional interactions in intestinal cadmium uptake--possibilities for risk reduction.  

PubMed

Effects of dietary composition and trace element status on fractional intestinal cadmium uptake is reviewed below. Fractional cadmium uptake is of fundamental importance for internal dose, related individual susceptibility to cadmium, induced renal damage and eventually bone disease. Diet composition with regard to macronutrients has some effects on cadmium bioavailability. Major determinants of intestinal cadmium uptake are however diet composition with regard to crude fibres and trace elements, especially iron. Deficiencies may increase intestinal cadmium uptake 5-8 times. Ultimate risk management would be not to raise crops on cadmium polluted soil. Provisionally, assurance of optimal trace element statusin persons exposed to cadmium is essential for risk reduction. PMID:15688861

Andersen, Ole; Nielsen, Jesper B; Nordberg, Gunnar F

2004-10-01

359

Table of interplanar spacings for crystal-structure determinations by X-ray diffraction with molybdenum, copper, cobalt, iron, and chromium radiations  

NASA Technical Reports Server (NTRS)

For a simple diffraction pattern, the time required to calculate interplanar distances from measurements of the pattern is not excessive. If more than a few lines are present, however, or if several patterns are to be studied, it is very advantageous to have available a table giving interplanar spacings directly in terms of the linear measurements made on the film of the lines appearing on the diffraction pattern. The preparation of the table given here was undertaken when the expansion of research activities involving X-ray diffraction techniques indicated that such a table would greatly decrease the time required to analyze diffraction patterns. The table was prepared for use with K alpha(sub 1) radiation from the following target materials: molybdenum, copper, cobalt, iron, and chromium.

Kittel, J Howard

1945-01-01

360

Comparison of the levels of copper, zinc and iron in cervical mucus and in blood serum of women of childbearing age.  

PubMed

The objective of this research study was a preliminary comparison of some chosen trace elements concentrations in cervical mucus and blood serum of women of childbearing age. The levels of iron (Fe), copper (Cu) and zinc (Zn) were determined in cervical mucus and serum of 10 patients. The obtained results do not point to any association between the levels of the examined trace elements in cervical mucus or any correlation between their contents in mucus and blood serum. As no correlation was found between the blood serum and cervical mucus, as far as trace elements are concerned, one might suggest that the uptake of trace elements by the mucus has an active form. PMID:16145958

Kaczmarek, Andrzej; Robak-Cho?ubek, Dorota; Sowa, Ireneusz; Jakiel, Grzegorz

2004-01-01

361

[Preliminary study of the effect of supplementation of iron, copper, cobalt and zinc on cellulolytic activity in the cecum of the pony].  

PubMed

We studied a caecum-cannulated pony fed hay libitum in order to determine the mineral elements likely to cause deficiencies which decrease microbial activity in the caecum. During four successive 1-month periods, we observed the effects of adding 50 mg of iron, 1 mg of cobalt, 40 mg of copper and 200 mg of zinc, respectively. Except for the introduction of zinc, which greatly diminishes cellulolytic activity measured with the nylon bag technique, there was no significant modification in that activity as shown by pH, NH3-nitrogen, total nitrogen and volatile fatty acid production (table 1). It can be concluded that endogenous secretion in the pre-caecal part of the digestive system of the mineral elements used was sufficient to guarantee good symbiosis between the microbial population of the caecum and the organism. PMID:7349504

Tisserand, J L; Boulard, F; Deponge, P

1980-01-01

362

Evaluating In-Situ Reactions of Chlorine and Chloramines at the Surface of Copper and Iron using Microelectrodes  

EPA Science Inventory

Corrosion of drinking water plumbing materials is a significant cause of deterioration of treated drinking water quality and a failure to supply safe water to the public. As a result of the Lead and Copper Rule, many water utilities in the US have developed and evaluated corrosio...

363

Temporal trends in the concentration of arsenic, chromium, copper, iron, nickel, vanadium and zinc in mosses across Europe between 1990 and 2000  

NASA Astrophysics Data System (ADS)

The European heavy metals in mosses biomonitoring network provides data on the concentration of 10 heavy metals in naturally growing mosses and is currently coordinated by the UNECE ICP Vegetation (United Nations Economic Commission for Europe International Co-operative Programme on Effects of Air Pollution on Natural Vegetation and Crops). The technique of moss analysis provides a surrogate, time-integrated measure of metal deposition from the atmosphere to terrestrial systems. It is easier and cheaper, less prone to contamination and allows a much higher sampling density than conventional precipitation analysis. Moss surveys have been repeated at five-yearly intervals and in this paper we report on the temporal trends in the concentration of arsenic, chromium, copper, iron, nickel, vanadium and zinc between 1990 and 2000. Maps were produced of the metal concentration in mosses for 1990, 1995 and 2000, showing the mean concentration per metal per 50km×50km EMEP grid square. Metal- and country-specific temporal trends were observed. Although the metal concentration in mosses generally decreased with time for all metals, only the decreases for arsenic, copper, vanadium and zinc were statistically significant. The observed temporal trends were compared with emission trends for Europe reported by EMEP (Co-operative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutant in Europe).

Harmens, Harry; Norris, David A.; Koerber, Georgia R.; Buse, Alan; Steinnes, Eiliv; Rühling, Åke

364

Formation of nickel and copper ferrites in ceramics: a potential reaction in the reuse of iron-rich sludge incineration ash.  

PubMed

This study investigates potential solid-state reactions for the stabilization of hazardous metals when reusing the incineration ash from chemically enhanced primary treatment (CEPT) sludge to fabricate ceramic products. Nickel and copper were used as examples of hazardous metals, and the iron content in the reaction system was found to play a major role in incorporating these hazardous metals into their ferrite phases (NiFe2O4 and CuFe2O4). The results from three-hour sintering experiments on NiO + Fe2O3 and CuO + Fe2O3 systems clearly demonstrate the potential for initiating metal incorporation mechanisms using an iron-containing precursor at attainable ceramic sintering temperatures (above 750 degrees C). Both ferrite phases were examined using a prolonged leaching experiment modified from the widely used toxicity characteristic leaching procedure (TCLP) to evaluate their long-term metal leachability. The leaching results indicate that both the NiFe2O4 and the CuFe2O4 products were significantly superior to their oxide forms in immobilizing hazardous metals. PMID:23437648

Shih, Kaimin

2012-12-01

365

Calcium, potassium, iron, copper and zinc concentrations in the white and gray matter of the cerebellum and corpus callosum in brain of four genetic mouse strains  

NASA Astrophysics Data System (ADS)

In the central nervous system, metallic cations are involved in oligodendrocyte maturation and myelinogenesis. Moreover, the metallic cations have been associated with pathogenesis, particularly multiple sclerosis and malignant gliomas. The brain is vulnerable to either a deficit or an excess of available trace elements. Relationship between trace metals and myelinogenesis is important in understanding a severe human pathology : the multiple sclerosis, which remains without efficient treatment. One approach to understand this disease has used mutant or transgenic mice presenting myelin deficiency or excess. But to date, the concentration of trace metals and mineral elements in white and gray matter areas in wild type brain is unknown. The aim of this study is to establish the reference concentrations of trace metals (iron, copper and zinc) and minerals (potassium and calcium) in the white and gray matter of the mouse cerebellum and corpus callosum. The brains of four different genetic mouse strains (C57Black6/SJL, C57Black6/D2, SJL and C3H) were analyzed. The freeze-dried samples were prepared to allow PIXE (Proton-induced X-ray emission) and RBS (Rutherford backscattering spectrometry) analyses with the nuclear microprobe in Bordeaux. The results obtained give the first reference values. Furthermore, one species out of the fours testes exhibited differences in calcium, iron and zinc concentrations in the white matter.

Sergeant, C.; Vesvres, M. H.; Devès, G.; Guillou, F.

2005-04-01

366

SOURCES OF COPPER AIR EMISSIONS  

EPA Science Inventory

The report gives results of a study to update estimates of atmospheric emissions of copper and copper compounds in the U.S. Source categories evaluated included: metallic minerals, primary copper smelters, iron and steel making, combustion, municipal incineration, secondary coppe...

367

Copper, iron, zinc, and selenium dietary intake and status of Nepalese lactating women and their breast-fed infants13  

Microsoft Academic Search

The dietary intake ofcopper, iron, zinc, and selenium of26 Nepalese lactat- ing mothers was estimated from chemical analysis of24-h food and beverage composites. Fast- ing blood and milk samples were obtained from the mothers and blood samples were obtained from the infants. The Nepalese mothers consumed significantly more Cu, significantly less Fe and Se, and similar amounts of Zn as

Phylis B Moser; Robert D Reynolds; Suniti Acharya; M Pat Howard; Mark B Andon; Susan A Lewis

368

Changes in Fractions of Iron, Manganese, Copper, and Zinc in Soil under Continuous Cropping for More Than Three Decades  

Microsoft Academic Search

The effect of continuous cropping with maize and wheat on soil characteristics and various forms of micronutrient cations in an Incetisol over the years was studied in an ongoing long?term experiment in New Delhi, India. The soil samples collected in the years of 1993, 1995, 1997, 1999, 2001, 2003, and 2004 were analyzed for different fractions of iron (Fe), manganese

Sanjib Kumar Behera; Dhyan Singh; Brahma Swaroop Dwivedi

2009-01-01

369

Precipitation and Characterization of Arsenate Phases from Calcium-Copper-Iron-Arsenic Oxide-Sulfate Hydrothermal Systems  

NASA Astrophysics Data System (ADS)

The scope of this thesis is the study of three Fe(III)-As(V) hydrothermal systems. The first one is the Fe(III)-AsO4-SO 4 system and crystalline phases that are produced under high temperature (150-225°C); this was studied to clear up previous contradicting information on this system in relation to industrial arsenic products that are formed during the autoclave processing of arsenical sulphide gold feedstocks and asses their arsenic stability. The second system studied was Cu(II)-Fe(III)-AsO 4-SO4 system at 150°C; this was investigated due to its relevance to industrial pressure leaching of copper concentrates. This system was studied in order to examine the possible effect of copper on the precipitation of scorodite. Finally, the structural and molecular examination of two members of the Ca(II)-Fe(III)-AsO4 system, namely yukonite (synthetic and natural and arseniosiderite was undertaken due to their relatively unknown nature and the potential role play in controlling arsenic release in tailings.

Gomez, Mario Alberto

370

Magnetotelluric evidence for a deep-crustal mineralizing system beneath the Olympic Dam iron oxide copper-gold deposit, southern Australia  

NASA Astrophysics Data System (ADS)

The iron oxide copper-gold Olympic Dam deposit, situated along the margin of the Proterozoic Gawler craton, South Australia, is the world's largest uranium deposit and sixth-largest copper deposit; it also contains significant reserves of gold, silver, and rare earth elements. Gaining a better understanding of the mechanisms for genesis of the economic liberalization is fundamental for defining exploration models in similar crustal settings. To delineate crustal structures that may constrain mineral system fluid pathways, coincident deep crustal seismic and magnetotelluric (MT) transects were obtained along a 220 km section that crosses Olympic Dam and the major crustal boundaries. In this paper we present results from 58 long-period (10 104 s) MT sites, with site spacing of 5 10 km. A two-dimensional inversion of MT data from 33 sites to a depth of 100 km shows four notable features: (1) sedimentary cover sequences with low resistivity (<20 ?·m) thicken to 10 km toward the northern cover sequences of the Adelaide Rift Complex; (2) a northeast-dipping crustal boundary separates a highly resistive (>1000 ?·m) Archean crustal core from a more conductive crust and mantle to the north (typically <500 ?·m); (3) to the north of Olympic Dam, the upper-middle crust to ˜20 km is quite resistive (˜1000 ?·m), but the lower crust is much more conductive (<100 ?·m); and (4) beneath Olympic Dam, we image a low-resistivity region (<100 ?·m) throughout the crust, coincident with a seismically transparent region. We argue that the cause of the low-resistivity and low-reflectivity region beneath Olympic Dam may be due to the upward movement of CO2-bearing volatiles near the time of deposit formation that precipitated conductive graphite liberalization along grain boundaries, simultaneously annihilating acoustic impedance boundaries. The source of the volatiles may be from the mantle degassing or retrograde metamorphism of the lower crust associated with Proterozoic crustal deformation.

Heinson, Graham S.; Direen, Nicholas G.; Gill, Rob M.

2006-07-01

371

A validation of copper, nickel and iron data in endf\\/b-vi.2, jef-2.2 and jendl-3.2 through a series of br-1 critical core analysis  

Microsoft Academic Search

This report discusses the lessons learned from a validation of copper, nickel and iron data in ENDF\\/B-VI.2, JEF-2.2 and JENDL-3.2 through an analysis of 97.6 at. % 239PU metal fueled BR-1 fast reactor benchmarks. The specifications for the benchmarks in this study were taken from the ICSBEP handbook. The Monte Carlo code MCNP4B and continuous-energy cross-section libraries processed from the

Won-Guk Hwang; J KIM; S OH

1998-01-01

372

Correlations in distribution and concentration of calcium, copper and iron with zinc in isolated extracellular deposits associated with age-related macular degeneration.  

PubMed

Zinc (Zn) is abundantly enriched in sub-retinal pigment epithelial (RPE) deposits, the hallmarks of age-related macular degeneration (AMD), and is thought to play a role in the formation of these deposits. However, it is not known whether Zn is the only metal relevant for sub-RPE deposit formation. Because of their involvement in the pathogenesis of AMD, we determined the concentration and distribution of calcium (Ca), iron (Fe) and copper (Cu) and compared these with Zn in isolated and sectioned macular (MSD), equatorial (PHD) and far peripheral (FPD) sub-RPE deposits from an 86 year old donor eye with post mortem diagnosis of early AMD. The sections were mounted on Zn free microscopy slides and analyzed by microprobe synchrotron X-ray fluorescence (?SXRF). Metal concentrations were determined using spiked sectioned sheep brain matrix standards, prepared the same way as the samples. The heterogeneity of metal distributions was examined using pixel by pixel comparison. The orders of metal concentrations were Ca ? Zn > Fe in all three types of deposits but Cu levels were not distinguishable from background values. Zinc and Ca were consistently present in all deposits but reached highest concentration in MSD. Iron was present in some but not all deposits and was especially enriched in FPD. Correlation analysis indicated considerable variation in metal distribution within and between sub-RPE deposits. The results suggest that Zn and Ca are the most likely contributors to deposit formation especially in MSD, the characteristic risk factor for the development of AMD in the human eye. PMID:24740686

Flinn, Jane M; Kakalec, Peter; Tappero, Ryan; Jones, Blair; Lengyel, Imre

2014-07-01

373

Hydrogen bonding of sulfur ligands in blue copper and iron-sulfur proteins: detection by resonance raman spectroscopy  

SciTech Connect

The resonance Raman spectrum of the blue copper protein azurin from Alcaligenes denitrificans exhibits nine vibrational modes between 330 and 460 cm/sup -1/, seven of which shift 0.4-3.0 cm/sup -1/ to lower energy after incubation of the protein in D/sub 2/O. These deuterium-dependent shifts have been previously ascribed to exchangeable protons on imidazole ligands or to exchangeable protons on amide groups which are hydrogen bonded to the cysteine thiolate ligands (a feature common to all blue copper proteins of known structure). In order to distinguish between these two possibilities, a systematic investigation of Fe/sub 2/S/sub 2/(Cys)/sub 4/-containing proteins was undertaken. Extensive hydrogen bonding between sulfur ligands and the polypeptide backbone had been observed in the crystal structure of ferredoxin from Spirulina platensis. The resonance Raman spectrum of this protein is typical of a chloroplast-type ferredoxin and exhibits deuterium-dependent shifts of -0.3 to -0.5 cm/sup -1/ in the Fe-S modes at 283, 367, and 394 cm/sup -1/ and -0.6 to -0.8 cm/sup -1/ in the Fe-S modes at 328 and 341 cm/sup -1/. Considerably greater deuterium sensitivity is observed in the Raman spectra of spinach ferredoxin and bovine adrenodoxin, particularly for the symmetric stretching vibration of the Fe/sub 2/S/sub 2/ moiety at approx. 390 cm/sup -1/. This feature decreases of 9.8 and 1.1 cm/sup -1/, respectively, for the two oxidized proteins in D/sub 2/O and by 1.8 cm/sup -1/ for reduced adrenodoxin in D/sub 2/O. These results suggest that the bridging sulfido groups may be more extensively hydrogen bonded in spinach ferredoxin and adrenodoxin than in S. platensis ferredoxin, with a further increase in hydrogen-bond strength in the reduced form of adrenodoxin.

Mino, Y.; Loehr, T.M.; Wada, K.; Matsubara, H.; Sanders-Loehr, J.

1987-12-15

374

Transport and Fate of Copper in Soils  

Microsoft Academic Search

The presence of toxic heavy metals in industrial effluents is one of the serious threats to the environment. Heavy metals such as Cadmium, Chromium, Lead, Nickel, Zinc, Mercury, Copper, Arsenic are found in the effluents of industries such as foundries, electroplating, petrochemical, battery manufacturing, tanneries, fertilizer, dying, textiles, metallurgical and metal finishing. Tremendous increase of industrial copper usage and its

S K Sharma; N S Sehkon; S Deswal; Siby John

2009-01-01

375

Bis(2,2'-biquinoline)copper(I) nitrate as an in situ spectrophotometric probe of cadmium sulfide/cuprous sulfide heterojunction formation  

SciTech Connect

Amyl alcohol solutions of the bis(2,2'-biquinoline)copper(I) cation, I, react with single-crystal, n-type CdS to yield n-CdS/p-Cu/sub 2/S heterojunctions. The intense visible absorption band of I (lambda/sub max/ 545 nm; epsilon approx. 6300 M/sup -1/ cm/sup -1/ at 25/sup 0/C) provides an in situ spectrophotometric probe of heterojunction formation: spectral changes can be correlated with the extent of reaction. Kinetic studies using the nitrate salt of I reveal that initial reaction rates are directly proportional to CdS macroscopic surface area, first order in the concentration of I, and temperature dependent with an apparent activation energy of 13 +- 2 kcal/mol between 60 and 90/sup 0/C. Mechanistic aspects of the reaction are discussed.

Schlesener, C.J.; Streckert, H.H.; Ellis, A.B.

1981-12-01

376

A study of the kinetics and fate of zinc-65 and iron-59 mobilized from labeled ghosts by reticulocyte lysates of normal and cadmium-treated rabbits  

E-print Network

(12, 55, 56). lrcsh, nonsterile, pooled rabbit serum was ob- tained from Pel Fre& z Laboratories for use as starting mat& rial . A saturating amount of iron nitrilotriacetate was added to an aliquot of serum, assuming the concentration... (12, 55, 56). lrcsh, nonsterile, pooled rabbit serum was ob- tained from Pel Fre& z Laboratories for use as starting mat& rial . A saturating amount of iron nitrilotriacetate was added to an aliquot of serum, assuming the concentration...

McAleese, Kathryn Noel

2012-06-07

377

Effect of metallothionein core promoter region polymorphism on cadmium, zinc and copper levels in autopsy kidney tissues from a Turkish population  

SciTech Connect

Metallothioneins (MTs) are metal-binding, low molecular weight proteins and are involved in pathophysiological processes like metabolism of essential metals, metal ion homeostasis and detoxification of heavy metals. Metallothionein expression is induced by various heavy metals especially cadmium, mercury and zinc; MTs suppress toxicity of heavy metals by binding themselves to these metals. The aim of this study was to investigate the association between the - 5 A/G metallothionein 2A (MT2A) single nucleotide polymorphism (SNP) and Cd, Zn and Cu levels in the renal cortex from autopsy cases. MT2A core promoter region - 5 A/G SNP was analyzed by PCR-RFLP method using 114 autopsy kidney tissues and the genotype frequencies of this polymorphism were found as 87.7% homozygote typical (AA), 11.4% heterozygote (AG) and 0.9% homozygote atypical (GG). In order to assess the Cd, Zn and Cu levels in the same autopsy kidney tissues, a dual atomic absorption spectrophotometer system was used and the average levels of Cd, Zn and Cu were measured as 95.54 {+-} 65.58 {mu}g/g, 181.20 {+-} 87.72 {mu}g/g and 17.14 {+-} 16.28 {mu}g/g, respectively. As a result, no statistical association was found between the - 5 A/G SNP in the MT2A gene and the Zn and Cu levels in the renal cortex (p > 0.05), but considerably high accumulation of Cd was monitored for individuals having AG (151.24 {+-} 60.21 {mu}g/g) and GG genotypes (153.09 {mu}g/g) compared with individuals having AA genotype (87.72 {+-} 62.98 {mu}g/g) (p < 0.05). These results show that the core promoter region polymorphism of metallothionein 2A increases the accumulation of Cd in human renal cortex.

Kayaalti, Zeliha, E-mail: kayaalti@medicine.ankara.edu.t [Ankara University Institute of Forensic Medicine, Institute of Forensic Medicine, Ankara University, Dikimevi, 06590, Ankara (Turkey); Mergen, Goerkem; Soeylemezoglu, Tuelin [Ankara University Institute of Forensic Medicine, Institute of Forensic Medicine, Ankara University, Dikimevi, 06590, Ankara (Turkey)

2010-06-01

378

Aluminum, Iron, Lead, Cadmium, Copper, Zinc, Chromium, Magnesium, Strontium, and Calcium Content in Bone of End-Stage Renal Failure Patients  

Microsoft Academic Search

Background: Little is known about trace metal alter- ations in the bones of dialysis patients or whether particular types of renal osteodystrophy are associated with either increased or decreased skeletal concentra- tions of trace elements. Because these patients are at risk for alterations of trace elements as well as for morbidity from skeletal disorders, we measured trace elements in bone

Patrick C. D'Haese; Marie-Madeleine Couttenye; Ludwig V. Lamberts; Monique M. Elseviers; William G. Goodman; Iris Schrooten; Walter E. Cabrera; Marc E. De Broe

379

The effect of low doses of dietary cadmium oxide on the disposition of trace elements (zinc, copper, iron), hematological parameters, and liver function in rats  

Microsoft Academic Search

The Zn, Cu, and Fe concentrations in selected organs, tissues and in the excreta of male Wistar rats, exposed to dietary CdO (2.80 and 7.15 ppm) for 40 and 60 days, were investigated. Concomitantly hematological values and serum enzyme activities were recorded. Zn levels of spleen, kidney, testes, muscle and feces were not affected by the Cd treatment. After 40

H. J. Weigel; I. Elmadfa; H. J. Jäger

1984-01-01

380

Determination of iron, cobalt, nickel, manganese, zinc, copper, cadmium and lead in human hair by inductively coupled plasma-atomic emission spectrometry  

Microsoft Academic Search

A method was standardized for the dissolution of hair samples and analysis was carried out by inductively coupled plasma atomic emission spectrometry (ICP-AES). Hair samples were brought into solution by using a mixture of nitric acid and hydrogen peroxide. Various parameters that influence the sample preparation, namely temperature, digestion time and ratio of acid mixture were studied and standardized. The

K. Sreenivasa Rao; T. Balaji; T. Prasada Rao; Y. Babu; G. R. K. Naidu

2002-01-01

381

Cadmium-induced Cancers in Animals and in Humans  

PubMed Central

Discovered in the early 1800s, the use of cadmium and various cadmium salts started to become industrially important near the close of the 19th century, rapidly thereafter began to flourish, yet has diminished more recently. Most cadmium used in the United States is a byproduct from the smelting of zinc, lead, or copper ores, and is used to manufacture batteries. Carcinogenic activity of cadmium was discovered first in animals and only subsequently in humans. Cadmium and cadmium compounds have been classified as known human carcinogens by the International Agency for Research on Cancer and the National Toxicology Program based on epidemiologic studies showing a causal association with lung cancer, and possibly prostate cancer, and studies in experimental animals, demonstrating that cadmium causes tumors at multiple tissue sites, by various routes of exposure, and in several species and strains. Epidemiologic studies published since these evaluations suggest that cadmium is also associated with cancers of the breast, kidney, pancreas, and urinary bladder. The basic metal cationic portion of cadmium is responsible for both toxic and cardinogenic activity, and the mechanism of carcinogenicity appears to be multifactorial. Available information about the carcinogenicity of cadmium and cadmium compounds is reviewed, evaluated, and discussed. PMID:17718178

Huff, James; Lunn, Ruth M.; Waalkes, Michael P.; Tomatis, Lorenzo; Infante, Peter F.

2012-01-01

382

Minimization of lead and copper interferences on spectrophotometric determination of cadmium using electrolytic deposition and ion-exchange in multi-commutation flow system.  

PubMed

A new strategy for minimization of Cu(2+) and Pb(2+) interferences on the spectrophotometric determination of Cd(2+) by the Malachite green (MG)-iodide reaction using electrolytic deposition of interfering species and solid phase extraction of Cd(2+) in flow system is proposed. The electrolytic cell comprises two coiled Pt electrodes concentrically assembled. When the sample solution is electrolyzed in a mixed solution containing 5% (v/v) HNO(3), 0.1% (v/v) H(2)SO(4) and 0.5 M NaCl, Cu(2+) is deposited as Cu on the cathode, Pb(2+) is deposited as PbO(2) on the anode while Cd(2+) is kept in solution. After electrolysis, the remaining solution passes through an AG1-X8 resin (chloride form) packed minicolumn in which Cd(2+) is extracted as CdCl(4)(2-). Electrolyte compositions, flow rates, timing, applied current, and electrolysis time was investigated. With 60 s electrolysis time, 0.25 A applied current, Pb(2+) and Cu(2+) levels up to 50 and 250 mg l(-1), respectively, can be tolerated without interference. For 90 s resin loading time, a linear relationship between absorbance and analyte concentration in the 5.00-50.0 mug Cd l(-1) range (r(2)=0.9996) is obtained. A throughput of 20 samples per h is achieved, corresponding to about 0.7 mg MG and 500 mg KI and 5 ml sample consumed per determination. The detection limit is 0.23 mug Cd l(-1). The accuracy was checked for cadmium determination in standard reference materials, vegetables and tap water. Results were in agreement with certified values of standard reference materials and with those obtained by graphite furnace atomic absorption spectrometry at 95% confidence level. The R.S.D. for plant digests and water containing 13.0 mug Cd l(-1) was 3.85% (n=12). The recoveries of analyte spikes added to the water and vegetable samples ranged from 94 to 104%. PMID:18968135

Gomes Neto, J A; Oliveira, A P; Freshi, G P; Dakuzaku, C S; de Moraes, M

2000-12-01

383

Flame atomic absorption spectrometric (FAAS) determination of copper, iron and zinc in food samples after solid-phase extraction on Schiff base-modified duolite XAD 761.  

PubMed

The present study involves the development of solid-phase extraction (SPE) procedure for the preconcentration of trace amounts of copper (Cu(2+)), iron (Fe(3+)) and zinc (Zn(2+)) ions on duolite XAD 761 modified by bis(2-hydroxyacetophenone)-2,2-dimethyl-1,3-propanediimine(BHAPDMPDI). The complexation between the metal ions and the proposed ligand was investigated potentiometrically. The metal ions retained on the sorbent were quantitatively determined via complexation with BHAPDMPDI. The complexed metal ions were efficiently eluted using 6 mL of 4 mol L(-1) nitric acid in acetone. The influences of the analytical parameters, including pH, amounts of the ligand and the solid phase, eluent conditions and sample volume, on the recoveries of the metal ions were optimized. Using the optimized parameters, the linear response of the SPE method for Cu(2+), Zn(2+) and Fe(3+) ions were in the ranges of 0.01-0.34, 0.01-0.28 and 0.02-0.31 ?g mL(-1), respectively, and the detection limits for Cu(2+), Zn(2+) and Fe(3+) ions were 1.8, 1.6 and 2.4 ?g mL(-1), respectively. The proposed method exhibits a preconcentration factor of 208 for all of the ions studied and an enhancement factor for Cu(2+), Fe(3+) and Zn(2+) ions of 34, 28 and 38, respectively. The presented results demonstrate the successful application of the proposed method for the determination of these metal ions in some real samples with high recoveries (> 95%) and reasonable relative standard deviation (RDS <5%). PMID:23498267

Ghaedi, M; Mortazavi, K; Montazerozohori, M; Shokrollahi, A; Soylak, M

2013-05-01

384

Opacity of iron, nickel, and copper plasmas in the x-ray wavelength range: Theoretical interpretation of 2p-3d absorption spectra  

SciTech Connect

This paper deals with theoretical studies on the 2p-3d absorption in iron, nickel, and copper plasmas related to LULI2000 (Laboratoire pour l'Utilisation des Lasers Intenses, 2000J facility) measurements in which target temperatures were of the order of 20 eV and plasma densities were in the range 0.004-0.01 g/cm{sup 3}. The radiatively heated targets were close to local thermodynamic equilibrium (LTE). The structure of 2p-3d transitions has been studied with the help of the statistical superconfiguration opacity code sco and with the fine-structure atomic physics codes hullac and fac. A new mixed version of the sco code allowing one to treat part of the configurations by detailed calculation based on the Cowan's code rcg has been also used in these comparisons. Special attention was paid to comparisons between theory and experiment concerning the term features which cannot be reproduced by sco. The differences in the spin-orbit splitting and the statistical (thermal) broadening of the 2p-3d transitions have been investigated as a function of the atomic number Z. It appears that at the conditions of the experiment the role of the term and configuration broadening was different in the three analyzed elements, this broadening being sensitive to the atomic number. Some effects of the temperature gradients and possible non-LTE effects have been studied with the help of the radiative-collisional code scric. The sensitivity of the 2p-3d structures with respect to temperature and density in medium-Z plasmas may be helpful for diagnostics of LTE plasmas especially in future experiments on the {Delta}n=0 absorption in medium-Z plasmas for astrophysical applications.

Blenski, T.; Loisel, G.; Poirier, M.; Thais, F.; Arnault, P.; Caillaud, T.; Fariaut, J.; Gilleron, F.; Pain, J.-C.; Porcherot, Q.; Reverdin, C.; Silvert, V.; Villette, B.; Bastiani-Ceccotti, S.; Turck-Chieze, S.; Foelsner, W.; Gaufridy de Dortan, F. de [CEA, IRAMIS, Service 'Photons, Atomes et Molecules', Centre d'Etudes de Saclay, F-91191 Gif-sur-Yvette Cedex (France); CEA, DAM, DIF, F-91297 Arpajon (France); LULI, UMR No. 7605 CNRS - Ecole Polytechnique, F-91128 Palaiseau Cedex (France); CEA, IRFU, Service d'Astrophysique, Centre d'Etudes de Saclay, F-91191 Gif-sur-Yvette Cedex (France); Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); Institute of Nuclear Fusion, Universidad Politecnica de Madrid, Spain and Laboratoire d'Optique Appliquee, ENSTA-Paritech-Polytechnique, Chemin de la Huniere, F-91671 Palaiseau (France)

2011-09-15

385

Induction of metallothionein synthesis in rainbow trout, Salmo gairdneri , during long-term exposure to waterborne cadmium  

Microsoft Academic Search

Rainbow trout were exposed to 200 µg cadmium\\/l in the water during four months at 6–10°C. The liver, kidney and gills were analyzed for cadmium, copper, zinc, metallothionein and metallothionein mRNA. Cadmium accumulated in all three organs and reached the highest concentration in the kidney. The tissue zine and copper concentrations showed no major alterations during the experiment. The cytosolic

Per-Erik Olsson I; Åke Larsson; Amund Maage; Carl Haux; Keith Bonham; Muhammad Zafarullah; Lashitew Gedamu

1989-01-01

386

Sources of cadmium in the environment.  

PubMed

This paper is concerned with quantifying the major sources of cadmium in the European Community and assessing the relative significance of such inputs to the environmental compartments, air, land, and water. The methodology involved identification of potential sources of cadmium, including natural processes, as well as those associated with human activities. This was followed by a review of any emission studies of these processes and subsequent estimation of an emission factor for each source. The emission factor was applied to the most recent production or consumption data for the process in question to obtain an estimate of the annual discharge. The steel industry and waste incineration, followed by volcanic action and zinc production, are estimated to account for the largest emissions of atmospheric cadmium in the region. Waste disposal results in the single largest input of cadmium to land; the quantity of cadmium associated with this source is greater than the total from the four other major sources--coal combustion, iron and steel production, phosphate fertilizer manufacture and use, and zinc production. The characterization of cadmium inputs to aquatic systems is incomplete but of the sources considered, the manufacture of cadmium-containing articles accounts for the largest discharge, followed by phosphate fertilizer manufacture and zinc production. PMID:6303746

Hutton, M

1983-02-01

387

Spatial and temporal zoning of hydrothermal alteration and mineralization in the Sossego iron oxide-copper-gold deposit, Carajás Mineral Province, Brazil: paragenesis and stable isotope constraints  

NASA Astrophysics Data System (ADS)

The Sossego iron oxide-copper-gold deposit (245 Mt @ 1.1% Cu, 0.28 g/t Au) in the Carajás Mineral Province of Brazil consists of two major groups of orebodies (Pista-Sequeirinho-Baiano and Sossego-Curral) with distinct alteration assemblages that are separated from each other by a major high angle fault. The deposit is located along a regional WNW-ESE-striking shear zone that defines the contact between metavolcano-sedimentary units of the ˜2.76 Ga Itacaiúnas Supergroup and tonalitic to trondhjemitic gneisses and migmatites of the ˜2.8 Ga Xingu Complex. The deposit is hosted by granite, granophyric granite, gabbro, and felsic metavolcanic rocks. The Pista-Sequeirinho-Baiano orebodies have undergone regional sodic (albite-hematite) alteration and later sodic-calcic (actinolite-rich) alteration associated with the formation of massive magnetite-(apatite) bodies. Both these alteration assemblages display ductile to ductile-brittle fabrics. They are cut by spatially restricted zones of potassic (biotite and potassium feldspar) alteration that grades outward to chlorite-rich assemblages. The Sossego-Curral orebodies contain weakly developed early albitic alteration and very poorly developed subsequent calcic-sodic alteration. These orebodies contain well-developed potassic alteration assemblages that were formed during brittle deformation that resulted in the formation of breccia bodies. Breccia matrix commonly displays coarse mineral infill suggestive of growth into open space. Sulfides in both groups of deposits were precipitated first with potassic alteration and more importantly with a later assemblage of calcite-quartz-epidote-chlorite. In the Sequeirinho orebodies, sulfides range from undeformed to deformed; sulfides in the Sossego-Curral orebodies are undeformed. Very late, weakly mineralized hydrolytic alteration is present in the Sossego/Currral orebodies. The sulfide assemblage is dominated by chalcopyrite with subsidiary siegenite, and millerite. Pyrrhotite and pyrite are minor constituents of ore in the Sequerinho orebodies while pyrite is relatively abundant in the Sossego-Curral bodies. Oxygen isotope partitioning between mineral pairs constrains temperatures in the deposit spatially and through time. In the Sequeirinho orebody, the early sodic-calcic alteration stage was characterized by temperatures exceeding 500°C and ? ^{{{text{18}}}} {text{O}}_{{{text{H}}_{{text{2}}} {text{O}}}} values for the alteration fluid of 6.9 ± 0.9‰. Temperature declines outward and upward from the zone of most intense alteration. Paragenetically later copper-gold mineralization displays markedly lower temperatures (<300°C) and was characterized by the introduction of 18O-depleted hydrothermal fluids -1.8 ± 3.4‰. The calculated ?DH2O and ? ^{{{text{18}}}} {text{O}}_{{{text{H}}_{{text{2}}} {text{O}}}} values suggest that the fluids that formed the early calcic-sodic alteration assemblage were of formational/metamorphic or magmatic origin. The decrease of ? ^{{{text{18}}}} {text{O}}_{{{text{H}}_{{text{2}}} {text{O}}}} values through time may reflect influx of surficially derived waters during later alteration and mineralization events. Influx of such fluids could be related to episodic fluid overpressure, resulting in dilution and cooling of the metalliferous fluid, causing deposition of metals transported as metal chloride complexes.

Monteiro, Lena V. S.; Xavier, Roberto P.; de Carvalho, Emerson R.; Hitzman, Murray W.; Johnson, Craig A.; de Souza Filho, Carlos Roberto; Torresi, Ignácio

2008-02-01

388

Tourmaline B-isotopes fingerprint marine evaporites as the source of high-salinity ore fluids in iron oxide copper-gold deposits, Carajás Mineral Province (Brazil)  

NASA Astrophysics Data System (ADS)

The Carajás Mineral Province in northern Brazil containsa variety of world-class (>100 Mt ore) iron oxide copper-gold(IOCG) deposits, including the only Archean examples of thisdeposit class (e.g., the Igarapé Bahia/Alemãoand Salobo deposits). Tourmaline of schorl-dravite composition,a common gangue mineral in these deposits, precipitated shortlyprior to and after the ore assemblage. A boron isotope studyof texturally different tourmaline from three IOCG deposits(Igarapé Bahia, Salobo, and Sossego) using secondaryion mass spectrometry (SIMS) provides new evidence in the long-standingdebate of magmatic versus non-magmatic sources for the highsalinity (up to 50 wt% NaCl equiv.) of ore fluids in these deposits.Values of {delta}11B from 14{per thousand} to 26.5{per thousand} for the Igarapé Bahia andSalobo deposits confirm marine evaporite-derived brinesin the ore fluids, whereas lower {delta}11B values for the IgarapéBahia deposit (5.8{per thousand} to 8.8{per thousand}) suggest that these fluids may havemixed with an isotopically different hydrothermal fluid, orone that had a mixed boron source. More variable and isotopicallylighter boron in tourmaline from the Sossego deposit (-8{per thousand}to 11{per thousand}) is attributed to mixed sources, including light boronleached from felsic intrusive and volcanic host rocks, and heavyboron derived from marine evaporites. The boron isotope dataindicate that the characteristic high salinity of the ore fluidsin the Carajás Mineral Province was acquired by the interactionof hydrothermal fluids with marine evaporites. For IOCG depositsthat contain tourmaline as a common gangue mineral, boron isotopesoffer a valuable tool to constrain the high-salinity sourceproblem, which is a critical issue in metallogenesis of IOCGdeposits worldwide.

Perez Xavier, Roberto; Wiedenbeck, Michael; Trumbull, Robert B.; Dreher, Ana M.; Monteiro, Lena V. S.; Rhede, Dieter; de Araújo, Carlos E. G.; Torresi, Ignacio

2008-09-01

389

Combined effects of hydrographic structure and iron and copper availability on the phytoplankton growth in Terra Nova Bay Polynya (Ross Sea, Antarctica)  

NASA Astrophysics Data System (ADS)

Surface water (<100 m) samples were collected from the Terra Nova Bay polynya region of the Ross Sea (Antarctica) in January 2006, with the aim of evaluating the individual and combined effects of hydrographic structure, iron and copper concentration and availability on the phytoplankton growth. The measurements were conducted within the framework of the Climatic Long Term Interaction for the Mass-balance in Antarctica (CLIMA) Project of the Programma Nazionale di Ricerca in Antartide activities. Dissolved oxygen, nutrients, phytoplankton pigments and concentration and complexation of dissolved trace metals were determined. Experimental data were elaborated by Principal Component Analysis (PCA). As a result of solar heating and freshwater inputs from melting sea-ice, the water column was strongly stratified with an Upper Mixed Layer 4-16 m deep. The integrated Chl a in the layer 0-100 m ranged from 60 mg m-2 to 235 mg m-2, with a mean value of 138 mg m-2. The pigment analysis showed that diatoms dominated the phytoplankton assemblage. Major nutrients were generally high, with the lowest concentration at the surface and they were never fully depleted. The Si:N drawdown ratio was close to the expected value of 1 for Fe-replete diatoms. We evaluated both the total and the labile dissolved fraction of Fe and Cu. The labile fraction was operationally defined by employing the chelating resin Chelex-100, which retains free and loosely bound trace metal species. The total dissolved Fe ranged from 0.48 to 3.02 nM, while the total dissolved Cu from 3.68 to 6.84 nM. The dissolved labile Fe ranged from below the detection limit (0.15 nM) to 1.22 nM, and the dissolved labile Cu from 0.31 to 1.59 nM, respectively. The labile fractions measured at 20 m were significantly lower than values in 40-100 m samples. As two stations were re-sampled 5 days later, we evaluated the short-term variability of the physical and biogeochemical properties. In particular, in a re-sampled station at 20 m, the total dissolved Fe increased and the total dissolved Cu decreased, while their labile fraction was relatively steady. As a result of the increase in total Fe, the percentage of the labile Fe decreased. An increase of the Si:N, Si:P and Si:FUCO ratios was measured also in the re-sampled station. On this basis, we speculated that a switch from a Fe-replete to a Fe-deplete condition was occurring.

Rivaro, Paola; Luisa Abelmoschi, Maria; Grotti, Marco; Ianni, Carmela; Magi, Emanuele; Margiotta, Francesca; Massolo, Serena; Saggiomo, Vincenzo

2012-04-01

390

Effects of free iron oxyhydrates and soil organic matter on copper sorption-desorption behavior by size fractions of aggregates from two paddy soils.  

PubMed

Effects of free iron oxyhydrates (Fe(d)) and soil organic matter (SOM) on copper (Cu2+) sorption-desorption behavior by size fractions of aggregates from two typical paddy soils (Ferric-Accumulic Stagnic Anthrosol (Soil H) and Gleyic Stagnic Anthrosol (Soil W)) were investigated with and without treatments of dithionite-citrate-bicarbonate and of H2O2. The size fractions of aggregates were obtained from the undisturbed bulk topsoil using a low energy ultrasonic dispersion procedure. Experiments of equilibrium sorption and subsequent desorption were conducted at soil water ratio of 1:20, 25 degrees C. For Soil H, Cu2+ sorption capacity of the DCB-treated size fractions was decreased by 5.9% for fine sand fraction, by 40.4% for coarse sand fraction, in comparison to 2.9% for the bulk sample. However, Cu2+ sorption capacities of the H2O2-treated fractions were decreased by over 80% for the coarse sand fraction and by 15% for the clay-sized fraction in comparison to 88% for bulk soil. For Soil W, Cu2+ sorption capacity of the DCB-treated size fraction was decreased by 30% for the coarse sand fraction and by over 75% for silt sand fraction in comparison to 44.5% for the bulk sample. Cu2+ sorption capacities of the H2O2-treated fractions were decreased by only 2.0% for the coarse sand fraction and by 15% for the fine sand fraction in comparison to by 3.4% for bulk soil. However, Cu2+ desorption rates were increased much in H2O2-treated samples by over 80% except the clay-sized fraction (only 9.5%) for Soil H. While removal of SOM with H2O2 tendend to increase the desorption rate, DCB- and H2O2-treatments caused decrease in Cu2+ retention capacity of size fractions. Particularly, there hardly remained Cu2+ retention capacity by size fractions from Soil H after H2O2 treatment except for clay-sized fraction. These findings supported again the dominance of the coarse sand fraction in sorption of metals and the preference of absorbed metals bound to SOM in differently stabilized status among the size fractions. Thus, enrichment and turnover of SOM in paddy soils may have great effects on metal retention and chemical mobility in paddy soils. PMID:20108663

Wang, Fang; Pan, Genxing; Li, Lianqing

2009-01-01

391

Effect of natural organic materials on cadmium and neptunium sorption  

SciTech Connect

In a batch sorption study of the effect of naturally occurring organic materials on the sorption of cadmium and neptunium on oxides and tuff surfaces, the model sorbents were synthetic goethite, boehmite, amorphous silicon oxides, and a crushed tuff material from Yucca Mountain, Nevada. An amino acid, 3-(3,4-dihydroxypheny)-DL-alanine (DOPA), and an aquatic-originated fulvic material, Nordic aquatic fulvic acid (NAFA), were used as model organic chemicals. Sorption isotherm results showed that DOPA sorption followed the order aluminum oxide > iron oxide > silicon oxide and that the amount of DOAP sorption for a given sorbent increased as the solution pH was raised. The sorption of cadmium and neptunium on the iron oxide was about ten times higher than that on the aluminum oxide. The sorption of cadmium and neptunium on natural tuff material was much lower than that on aluminum and iron oxides. The sorption of cadmium on iron and aluminum oxides was found to be influenced by the presence of DOPA, and increasing the amount of DOPA coating resulted in higher cadmium sorption on aluminum oxide. However, for iron oxide, cadmium sorption decreased with increasing DOPA concentration. The presence of the model organic materials DOPA and NAFA did not affect the sorption of neptunium on tuff material or on the iron and aluminum oxides. Spectroscopic results indicate that cadmium complexes strongly with DOPA. Therefore, the effect of the organic material, DOPA, on the cadmium sorption is readily observed. However, neptunium is possibly complexed weakly with organic material. Thus, DOPA and NAFA have little effect on neptunium sorption on all sorbents selected for study.

Kung, K.S.; Triay, I.R.

1994-10-01

392

Remediation progress at the Iron Mountain Mine Superfund site, California. Information Circular/1991  

SciTech Connect

The report was prepared by the U.S. Bureau of Mines to present a brief history of the listing of Iron Mountain Mine as a Superfund site on the National Priorities List (NPL) and subsequent remedial actions. The mine area is located on 4,400 acres near Redding, CA, and includes underground workings, an open pit area, waste rock dumps, and tailings piles. The property involves multiple sources of acid mine drainage (AMD) that are high in copper, zinc, and cadmium. The selected remedial actions, based on the Record of Decision of 1986, would partially cap the richmond mineralized zone to reduce infiltration of clean water, divert clean surface waters away from contaminated areas, fill surface subsidence areas, and enlarge the Spring Creek debris dam to provide increased surge capacity. Site remediation efforts at Iron Mountain are well into the remedial design-remedial action phase. Details of activities and designs of remedial elements are presented, and future activities, discussed.

Biggs, F.R.

1991-01-01

393

Cadmium carcinogenesis in review  

Microsoft Academic Search

Cadmium is an inorganic toxicant of great environmental and occupational concern which was classified as a human carcinogen in 1993. Occupational cadmium exposure is associated with lung cancer in humans. Cadmium exposure has also, on occasion, been linked to human prostate cancer. The epidemiological data linking cadmium and pulmonary cancer are much stronger than for prostatic cancer. Other target sites

Michael P Waalkes

2000-01-01

394

A fungal multicopper oxidase restores iron homeostasis in aceruloplasminemia.  

PubMed

Mutations that lead to a loss of the copper-containing plasma enzyme ceruloplasmin disrupt mammalian iron homeostasis. The mechanism by which ceruloplasmin mobilizes iron from cell stores has been controversial. We demonstrate that injection of a soluble copper-containing yeast protein Fet3p can restore iron homeostasis in phlebotomized mice with a deletion of the ceruloplasmin gene. These results show the conservation of function of copper-containing proteins in eukaryotic iron metabolism. PMID:14739215

Harris, Z Leah; Davis-Kaplan, Sandra R; Gitlin, Jonathan D; Kaplan, Jerry

2004-06-15

395

Copper Test  

MedlinePLUS

... 3. What happens if I am exposed to toxic amounts of copper? Copper poisoning can cause vomiting ... Asked Questions American Cancer Society: Copper Agency for Toxic Substances and Disease Registry: Public Health Statement for ...

396

Identification of iron Superoxide dismutase and a copper\\/zinc Superoxide dismutase enzyme activity within the marine cyanobacterium Synechococcus sp. WH 7803  

Microsoft Academic Search

Three constitutive forms of Superoxide dismutase activity have been demonstrated in the cyanobacterial marine picoplankter Synechococcus sp. WH 7803 using polyacrylamide gel activity staining techniques. A protein which gave a positive non-haem iron stain on native polyacrylamide gels exhibited N-terminal similarity to both the iron Superoxide dismutase and the manganese Superoxide dismutase of Escherichia coli. The metal prosthetic group of

Helen E Chadd; Julie Newman; Nicholas H Mann; Noel G Carr

1996-01-01

397

[Role of lysosomes in the phenomenon of cadmium concentration. Microanalysis by X-ray spectrography].  

PubMed

Investigations were performed on the midgut gland cells of the Crayfish Pontastacus leptodactylus after intoxication with cadmium. The storage of cadmium occurs within the lysosomes where the mental coexists always with sulfur zinc and copper. The simultaneous presence of these elements favours the hypothesis that metallothioneins may be located within the lysosomes. PMID:6796209

Chassard-Bouchaud, C

1981-10-12

398

Trophic transfer of metals along freshwater food webs: Evidence of cadmium biomagnification in nature  

Microsoft Academic Search

We conducted a study with cadmium (Cd) and copper (Cu) in the delta of San Francisco Bay, using nitrogen and carbon stable isotopes to identify trophic position and food web structure. Cadmium is progressively enriched among trophic levels in discrete epiphyte-based food webs composed of macrophyte-dwelling invertebrates (the first link being epiphytic algae) and fishes (the first link being gobies).

Marie-Noële Croteau; Samuel N. Luoma; A. Robin Stewart

2005-01-01

399

Hydrothermal alteration, fluid inclusions and stable isotope systematics of the Alvo 118 iron oxide-copper-gold deposit, Carajás Mineral Province (Brazil): Implications for ore genesis  

NASA Astrophysics Data System (ADS)

The Alvo 118 iron oxide-copper-gold (IOCG) deposit (170 Mt at 1.0 wt.% Cu, 0.3 g/t Au) lies in the southern sector of the Itacaúnas Shear Belt, Carajás Mineral Province, along a WNW-ESE-striking, 60-km-long shear zone, close to the contact of the ~2.76-Ga metavolcano-sedimentary Itacaiúnas Supergroup and the basement (~3.0 Ga Xingu Complex). The Alvo 118 deposit is hosted by mafic and felsic metavolcanic rocks and crosscutting granitoid and gabbro intrusions that have been subjected to the following hydrothermal alteration sequence towards the ore zones: (1) poorly developed sodic alteration (albite and scapolite); (2) potassic alteration (biotite or K-feldspar) accompanied by magnetite formation and silicification; (3) widespread, pervasive chlorite alteration spatially associated with quartz-carbonate-sulphide infill ore breccia and vein stockworks; and (4) local post-ore quartz-sericite alteration. The ore assemblage is dominated by chalcopyrite (~60%), bornite (~10%), hematite (~20%), magnetite (10%) and subordinate chalcocite, native gold, Au-Ag tellurides, galena, cassiterite, F-rich apatite, xenotime, monazite, britholite-(Y) and a gadolinite-group mineral. Fluid inclusion studies in quartz point to a fluid regime composed of two distinct fluid types that may have probably coexisted within the timeframe of the Cu-Au mineralizing episode: a hot (>200°C) saline (32.8‰ to 40.6 wt.% NaCl eq.) solution, represented by salt-bearing aqueous inclusions, and a lower temperature (<200°C), low to intermediate salinity (<15 wt.% NaCl eq.) aqueous fluid defined by two-phase (LH2O + VH2O) fluid inclusions. This trend is very similar to those defined for other IOCG systems of the Carajás Mineral Province. ? 18OH2O values in equilibrium with calcite (-1.0‰ to 7.5‰ at 277°C to 344°C) overlap the lower range for primary magmatic waters, but the more 18O-depleted values also point to the involvement of externally derived fluids, possibly of meteoric origin. Furthermore, sulphide ? 34S values (5.1‰ to 6.3‰), together with available boron isotope and Cl/Br-Na/Cl data provide evidence for a significant component of residual evaporative fluids (e.g., bittern fluids generated by seawater evaporation) in this scenario that, together with magma-derived brines, would be the main sources of the highly saline fluids involved in the formation Alvo 118 IOCG deposit. The restricted high temperature sodic alteration, the pervasive overprinting of the potassic alteration minerals by chlorite proximal to the ore zones, ore breccias with open-space filling textures in brittle structures, microthermometric and stable isotope data indicate, collectively, that the Alvo 118 IOCG system developed at structurally high levels and may be considered the shallower representative of the IOCG systems of the CMP.

Torresi, Ignacio; Xavier, Roberto Perez; Bortholoto, Diego F. A.; Monteiro, Lena V. S.

2012-03-01

400

Copper in microbial pathogenesis: meddling with the metal  

PubMed Central

Transition metals such as iron, zinc, copper and manganese are essential for the growth and development of organisms ranging from bacteria to mammals. Numerous studies have focused on the impact of iron availability during bacterial and fungal infections, and increasing evidence suggests that copper is also involved in microbial pathogenesis. Not only is copper an essential co-factor for specific microbial enzymes, but several recent studies also strongly suggest that copper is used to restrict pathogen growth in vivo. Here, we review evidence that animals use copper as an anti-microbial weapon and, in turn, microbes have developed mechanisms to counteract the toxic effects of copper. PMID:22341460

Samanovic, Marie I.; Ding, Chen; Thiele, Dennis J.; Darwin, K. Heran

2012-01-01