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PubMed2006

Selenium, iron, copper, and zinc levels and copper-to-zinc ratios in serum of patients at different stages of viral hepatic diseases.

Viral hepatic diseases, especially those induced by the hepatitis B virus, can progress into more serious pathological outcomes and eventually to hepatocellular carcinoma. A growing body of evidence indicates that many trace elements play important roles in a number of carcinogenic processes that proceed through various mechanisms. To examine the status of trace elements during the development of hepatic carcinoma, we determined the selenium, iron, copper, and zinc levels and copper-to-zinc ratios in the serum of patients at different stages of viral hepatic disease. We observed significant changes in the selenium, iron, copper, and zinc levels in the serum of patients having hepatocellular carcinoma, relative to those of healthy controls (p < 0.05). The mean serum copper level in patients with hepatocellular carcinoma was significantly higher than that of the control group. In contrast, the mean selenium, iron, and zinc levels in patients having hepatocellular carcinoma were significantly lower than those of the control group. In addition, the mean zinc level in the serum of patients with hepatic cirrhosis was significantly lower than that of the control group (p < 0.05). Moreover, we found markedly elevated Cu: Zn ratios (p < 0.05) in patients having hepatic cirrhosis or hepatocellular carcinoma. Our findings imply that the levels of some trace elements, such as selenium, iron, copper, and zinc, and Cu: Zn ratios, might serve as biomarkers for the increased severity of viral hepatic damage.

Adolescent↗
PubMed2004

Toxicity of binary mixtures of cadmium-copper and carbendazim-copper to the nematode Caenorhabditis elegans.

For ecological risk assessment, the additive model may be used to empirically predict toxic mixture effects. Detailed toxicity tests were performed to determine whether effects of mixtures of copper-cadmium and copper-carbendazim on Caenorhabditis elegans were similar to the effects of the individual compounds. Effects on the course of reproduction, the length of the juvenile period, the length of the reproductive period, and body length were analyzed. Dose-response data were compared to the additive model and tested for four deviation patterns from additivity: No deviation, synergistic/antagonistic deviation, dose ratio-dependent deviation, dose level-dependent deviation. During the exposure, the cadmium-copper effect on reproduction changed from a synergistic, to a dose ratio-dependent deviation from additivity. More cadmium in the mixture decreased the toxicity and more copper increased the toxicity. The effect of copper-carbendazim on reproduction was synergistic at low dose levels and antagonistic at high dose levels and independent of time. Mixture effects on the juvenile and reproductive period were similar to single component effects. It was concluded that the observed time-dependence of toxic interactions was small and that interactions on the timing of reproduction were not found. The additive model underestimated mixture effects on reproduction and body length.

Animals↗
PubMed1979

The interaction of divalent copper and the microsomal electron transport system. A re-examination of the effects of copper chelates on the function of cytochrome P-450.

Lipophilic chelates of divalent copper, possessing superoxide dismutase-like activity, have been proposed to enhance the decay of oxycytochrome P-450 to explain their inhibitory effect on microsomal mixed-function oxidation reactions (Richter, C., Azzi, A., Weser, U., and Wendel, A. (1977) J. Biol. Chem. 252, 5061-5066). The present investigation, however, failed to provide evidence in favor of this hypothesis. In particular, it was found that the reported inhibition of cytochrome P-450-catalyzed hydroxylation reactions by copper-tyrosine is associated with an inhibition rather than a stimulation of the formation of hydrogen peroxide, the product of the dismutation of the superoxide radicals generated as a result of the decay of oxycytochrome P-450. The attenuation of both these reactions was shown to be the consequence of an impaired function of the NADPH-cytochrome P-450 reductase. Additional sites of interaction of copper chelates and the microsomal electron transport system appear to exist since divalent copper was found to undergo reduction reactions with NADPH and NADH as electron donors. These reduction reactions do not involve superoxide radicals and, therefore, are unrelated to the ability of copper chelates to function in a superoxide dismutase-like manner.

Animals↗
PubMed1989

Enhancement of tetrathiomolybdate-induced biliary copper excretion in sheep by general anaesthesia and the effect on copper excretion in urine and bile.

To determine whether copper removed from the liver by tetrathiomolybdate (TTM) but not excreted in bile, is excreted in saliva or urine, the effect of an intravenous injection of 100 mg of TTM, as ammonium tetrathiomolybdate, on copper excretion by these routes was measured in conscious sheep and sheep maintained under general anaesthesia. During 4.5 hours the total amount of copper excreted in bile in the untreated, conscious animal was 0.52 +/- 0.04 mumols (mean +/- SE). A dose of 100 mg TTM increased excretion by an average of 11.7-fold to 6.06 +/- 0.29 mumols. Under halothane or barbiturate general anaesthesia copper excretion was increased 3.4-fold to 1.78 +/- 0.30 mumols. In anaesthetised sheep 100 mg TTM produced a 40.7-fold increase to 21.18 +/- 0.95 mumols. Neither anaesthesia nor TTM caused any increase in copper excretion in saliva or urine.

Anesthesia, General↗
PubMed1988

Evolutionary relationships among copper proteins containing coupled binuclear copper sites.

The amino acid sequences of different copper proteins containing coupled binuclear copper centers are compared. Hemocyanins from arthropods and molluscs and tyrosinases from three different species were found to share a highly homologous region in the C-terminal parts. This region contains three invariant histidines previously identified as ligands to Cu(B) in Panulirus interruptus hemocyanin by X-ray crystallography (Gaykema et al., Nature 309, 23-29 (1984]. In contrast, the ligand environment for the second copper, Cu(A), proved to be quite variable. It is proposed that hemocyanin and tyrosinase have arisen from a common mononuclear copper protein with the typical Cu(B) site. From this ancestral protein two types of binuclear proteins evolved independently into a tyrosinase and an arthropodan hemocyanin type. The amino acid sequence comparison between human ceruloplasmin and Neurospora crassa laccase together with the results from a preliminary X-ray structure analysis of zucchini ascorbate oxidase showed a close relationship in primary and most likely also in tertiary structure in the C-terminal parts of these enzymes. It is suggested that the multicopper oxidases have evolved from an ancestral copper protein which presumably contained all the ligands required for the binding of one binuclear and two additional mononuclear metal centers.

Animals↗
PubMed1986

[Serum copper and the copper:zinc ratio in patients with gastric cancer].

Serum copper levels, serum zinc levels, and serum Cu:Zn ratios were evaluated in 100 patients with gastric cancer. The following conclusions were drawn from the results: Serum copper levels and the serum Cu:Zn ratio were elevated, while serum zinc levels were decreased, reflecting the progress of the disease. Since serum zinc levels varied more remarkably, it was suggested that this value was more useful than serum copper levels as an indicator of tumor activity. Serum copper and zinc levels were independent of the presence of liver metastasis and of the histological types. It was shown that the serum copper levels correlated (significantly) to the survival time (p less than 0.005).

Adult↗
PubMed1985

[Evaluation of the exposure to copper and other non-ferrous metals in copper foundries].

Working environment has been evaluated in two copper metallurgy plants by analysis of Cu and other metals (Pb, Cd, Zn) concentrations. At the Charge Preparation Department the greatest concentrations of Cu and Pb were found. Copper concentrations at Metallurgy Department (shaft furnace, converter and anodic furnace) oscillate between 0.1-0.5 mg/m3, and Pb 0.06-0.71 mg/m3. In order to accurately evaluate copper exposure at working places where copper fume may arise (Metallurgy Department) it is necessary to determine Cu concentrations in respirable dust. At other working places Cu, Pb and Zn concentrations were low. Cadmium appears in vestigial amounts. The quantitative analysis indicates that airborne copper at the Charge Preparation Department and at the shaft furnace appears as CuS, at converter as Cu2O, and at other working places as metal Cu.

Air Pollutants, Occupational↗
PubMed1971

Effects of dietary copper loading on livers of rats. I. Changes in subcellular acid phosphatases and detection of an additional acid p-nitrophenylphosphatase in the cellular supernatant during copper loading.

Significant changes occurred in lysosomal structure and function as copper was metabolized by rat livers. Hepatic total acid p-nitrophenylphosphatase (pNphiPase) activity was markedly increased in copper-loaded rats, and this increase was almost completely accounted for by heat- and formalin-stable (HFS) acid pNphiPase. Heat- and formalin-labile acid pNphiPase was essentially unchanged. On a subcellular level, the microsomal and supernatant fractions reflected the greatest relative increase in HFS acid pNphiPase. Increases in lysosomal, HFS acid pNphiPase in the large-granule fractions correlated with increase in solubilized large-granule enzymes, LG I, with mol wt > 200,000. LG II, representng solubilized large-granule enzymes with mol wt < 200,000, remained unchanged. Marked increases in supernatant acid pNphiPase were principally accounted for by a sevenfold increase in a supernatant lysosomal-like enzyme, DEAE Pk 1, separated by DEAE cellulose chromatography. An additional enzyme, DEAE Pk 2A', that was hardly or not detectable in normal rats, was consistently demonstrated and increased in copper-loaded rats. Serum HFS acid pNphiPase increased in copper-loaded rats, suggesting that the increased hepatic supernatant acid pNphiPase in part escaped into the circulating fluid. Copper was principally associated with cytoplasmic organelles and was highest in mitochondrial and lysosomal fractions.

Acid Phosphatase↗
PubMed1981

Anemia of inflammatory disease in the dog: measurement of hepatic superoxide dismutase, hepatic nonheme iron, copper, zinc, and ceruloplasmin and serum iron, copper, and zinc.

Copper and iron are involved in protection of the aerobic cell from highly toxic oxygen by-products, one of which is the superoxide anion-free radical. This protection is associated with a copper-zinc enzyme, superoxide dismutase. Increased hepatic superoxide dismutase activity correlated directly with hepatic nonheme iron, serum zinc, and serum copper concentrations and inversely with hepatic copper, hepatic zinc, and serum iron concentrations (P less than 0.001). Decrease in hepatic ceruloplasmin concentration was correlated with the decrease in hepatic copper concentration (P less than 0.001).

Anemia↗
PubMed1995

[Effect of copper and copper binding protein on the CT attenuation value of liver: experimental study in rats].

We analyzed the effect of copper and copper binding protein on CT attenuation value in a rat model. CT attenuation values of the liver were compared with hepatic copper content and grade of orcein-positive granules, which are thought to be a counterpart of polymerized methalothionein in lysosomes. The difference between hepatic copper and CT attenuation value was not statistically significant (R = 0.056, p = 0.96). CT value had a positive correlation with the grade of orcein-positive granules (Rho = 0.755, p = 0.0001). We concluded that the CT attenuation value of liver can be elevated by rich polymerized methalothionein (copper binding protein) in lysosomes.

Animals↗
PubMed1993

[Bacterial reducing qualities of copper-containing and non-copper-containing materials. I. Contamination and sedimentation in humid and dry conditions].

In this examination the bactericide qualities of different materials were tested. Particularly the effect of humidity was examined. 3 materials containing copper ("copper", "brass" and "brass sheet") and 2 materials not containing copper ("polyamide B" and "high-grade steel") were tested. The surfaces of the 5 types of material were contaminated with a suspension of 2 different bacteria species (Staphylococcus aureus and Micrococcus luteus). After defined exposure times the survival rate of the microorganisms on the surfaces was determined by the standardized method of the "Guidelines of the German Society of Hygiene and Microbiology". Additionally the sedimentation of airborne microorganisms on the materials was tested by determining the number of colony-forming-units after defined exposure times. In further examinations the materials were contaminated by hands, which were dipped into a suspension of different microorganisms (Micrococcus luteus, Staphylococcus aureus, Enterococcus faecium, Escherichia coli, Enterobacter cloacae and Pseudomonas aeruginosa). The following ways of contaminating the test materials were chosen: single contamination with wet hands, repeated contamination with wet and dry hands. After defined exposure times the survival rate of the microorganisms on the surfaces was determined. The results show, a bactericide quality of copper depends on the percent of copper-content of the tested materials, exposure time, humidity, frequency of contamination and bacteria species. Humidity and only single contamination cause a reduction of bacteria. Reduction of gram-negative bacteria is more easily than reduction of gram-positive bacteria. Enterococcus faecium shows the highest, Pseudomonas aeruginosa the lowest reduction rate of bacteria in the following sequence: Enterococcus faecium, Escherichia coli, Enterobacter cloacae, Micrococcus luteus, Staphylococcus aureus and Pseudomonas aeruginosa.

Air Microbiology↗
PubMed1977

Hepatic copper content, urinary copper excretion, and serum ceruloplasmin in liver disease.

Increased liver copper concentration and raised serum ceruloplasmin were demonstrated in primary biliary cirrhosis and disorders of the biliary tract, and occasionally in chronic active hepatitis and cirrhosis of the liver. Eight of 13 patients with primary biliary cirrhosis had liver copper content as high as seen in patients with hepatolenticular degeneration (is greater than 250 mjg/g dry weight). Normal liver content was found in patients with acute hepatitis, steatosis of the liver, hepatic amuloidosis, haemochromatosis, and Gilbert's syndrome. The urinary copper excretion was increased (is greater than 75 mjg/24 h) in half the patients with primary biliary cirrhosis and occasionally in the other patient groups. Serum ceruloplasmin was raised in more than half of all patients, and none had levels below the reference range. Raised heaptic copper content did not always coincide with enhanced urinary copper excretion, but was significantly correlated with this parameter and also with ceruloplasmin, alkaline phosphatases, and vitamin-K-dependent clotting factors, but not with ALAT. Combination of laboratory data, as found in typical cases of hepatolenticular degeneration, was not observed in this study, including 66 patients.

Acute Disease↗
PubMed1990

Duration of use of copper releasing IUDs and the incidence of copper wire breakage.

The incidence of copper wire breakage for IUDs (Multiloads) using 0.3 and 0.4 mm diameter copper wire was evaluated by examining 969 devices that had been removed for various reasons. The IUDs were examined by light microscopy to determine the integrity of the copper wire. As expected, the incidence of breakage increased with increasing duration of IUD use. The cumulative breakage rate (life table) was significantly lower (p less than 0.05) for the Multiload 375 that used 0.4 mm diameter wire, compared to the Multiload 250 that used 0.3 mm diameter wire. The cumulative rates were 5.4 per 100 IUDs after 3 years for the Multiload 250, and 3.8 per 100 IUDs after 5 years for the Multiload 375. In only 1 (0.1%) of the 969 Multiloads examined, the breakage of the copper wire was sufficiently extensive to adversely affect the user's risk of pregnancy.

Equipment Failure↗
PubMed1998

Corrosion behavior of copper in a copper bearing intrauterine device in the presence of indomethacin.

As an improvement to the use of the copper bearing intrauterine device, indomethacin has been introduced to reduce the incidence of bleeding after insertion of the device. The effects of indomethacin on copper corrosion were studied in vitro in simulated uterine fluid. Electrochemical polarization resistance measurements indicated that indomethacin powder slightly increased the corrosion rate of copper if pH of the fluid was not under control and it did not change the corrosion rate if pH was adjusted daily to maintain some constancy. The experimental results for medication by indomethacin-releasing Silastic were basically the same as those with powdered indomethacin. X-ray diffraction showed that only cuprous oxide was formed on the copper substrated surface and that indomethacin did not affect the corrosion products. As scanning electron microscopy demonstrated, however, in the presence of indomethacin the oxide particles formed were found to be more coarse and dense than in the absence of indomethacin.

Body Fluids↗
PubMed2000

Surface and Texture Characterization of Alumina-Supported Copper and Mixed Copper-Manganese Oxide Catalysts and Their Formate Precursors.

Alumina-supported copper and copper-manganese oxide catalysts as well as the parent formates were characterized by means of FTIR spectroscopy in situ and nitrogen physisorption. The IR spectroscopic results are discussed on the basis of the deposition scheme proposed recently by Kapteijn et al. (J. Catal. 150, 94 (1994). The infrared bands in the high-frequency region (OH stretches) indicate that the aqueous copper species formed in the solutions are deposited on the basic and neutral surface OH groups, while as our previous studies show the aqueous manganese species are deposited on the basic and acidic OH groups. However, the aqueous manganese species are deposited on the basic and neutral OH groups in the presence of copper ions (pH 4.6-4.7). The deposition of the aqueous metal species on the protonated basic OH groups occurs as a result of the "ion-pairing" process. The driving forces resulting in the deposition of the aqueous metal species on the neutral OH groups are considered to be hydrogen bonds. The deposition of the formate ions is also discussed. The higher uptake of copper as compared to manganese is discussed in terms of the metal ion properties (electronic configuration, the ability to form hydrogen bonds of different strength, metal species-support interaction). The nitrogen physisorption shows that the initial mesoporous character of gamma-Al(2)O(3) structure does not change during impregnation. The r(FHH) values which characterized the adsorbent-adsorbate interaction forces are calculated. The comparative analysis of the pore size distribution curves of the oxide-supported samples and their parent formates proves to be a useful tool to elucidate the metal species-support interaction strength. Copyright 2000 Academic Press.

Journal Article↗
PubMed2005

Arsenic speciation in water samples containing high levels of copper: removal of copper interference affecting arsine generation by continuous flow solid phase chelation.

A simple continuous flow method is proposed to eliminate copper interference in arsenic speciation by hydride generation, based on the selective retention of this interfering ion in an iminodiacetate chelating resin previous to the hydride generation process. The arsines generated were cold trapped and measured by ICP/OES. The proposed method allows about 98% of the copper present in the samples to be removed. Minor co-retention of As(V) was observed as a result of electrostatic interaction between the arsenate anion and the nitrogen of the iminodiacetate group of the chelating resin Muromac A-1, the charge distribution of which is modified when copper is chelated. The species As(III), MMA and DMA were not retained in the microcolumn, probably because these species are mainly in the molecular form at the working pH value (4.5). In synthetic samples containing 50 microg l(-1) of each arsenic species together with 100 mg l(-1) copper, the recoveries obtained were: As(V) 97.6%, As(III) 100%, MMA 99.8%, and DMA 99.9%. The method was applied to arsenic speciation in river water samples containing high levels of copper.

Journal Article↗
PubMed1990

Effect of changing the type of dietary carbohydrate or copper level of copper-deficient, fructose-fed rats on tissue sorbitol concentrations.

This study was designed to examine the relationship between the fructose-copper interaction and tissue sorbitol concentrations. Weanling male rats were provided with a diet which contained 62.7% fructose and 0.6 microg copper/g (F-Cu) for 4 weeks. At this time, rats were changed to either a fructose diet which contained 6.0 microg copper/g or to a starch diet with or without copper for 2 weeks. When compared with the other dietary groups, it was found that rats fed the F-Cu diet grew poorly; had altered relative liver, pancreatic, heart, and kidney sizes; were anemic; and had higher tissue concentrations of pancreatic and heart glucose, liver, pancreatic, heart, and kidney fructose, and liver, pancreatic, and kidney sorbitol. When rats were changed from the F-Cu diet to one containing copper or to a starch diet with or without copper, weight gain, relative liver, pancreatic and heart sizes, and hematocrit improved significantly. In general, there was a reduction in pancreatic and heart glucose; liver, pancreatic, heart, and kidney fructose; and pancreatic and kidney sorbitol concentrations when rats were changed from the F-Cu diet to any of the other diets. We conclude that the fructose-copper interaction may have a common biochemical basis related to the metabolism of glucose, fructose, and sorbitol.

Journal Article↗
PubMed2001

Copper(II) complexes with 4-amino-N-[4,6-dimethyl-2-pyrimidinyl]benzenesulfonamide. Synthesis, crystal structure, magnetic properties, EPR, and theoretical studies of a novel mixed mu-carboxylato, NCN-bridged dinuclear copper compound.

New Cu(II) complexes of sulfamethazine (4-amino-N-[4,6-dimethyl-2-pyrimidinyl]benzenesulfonamide, HL) [Cu(2)(CH(3)COO)(2)(L)(2)].2dmf (1) and ([Cu(L)(2)].2H(2)O)(infinity) (2) were prepared and structurally characterized. Compound 1 crystallizes in the monoclinic system, space group P2(1)/n, with a = 8.9486(9) A, b = 15.0956(12) A, c = 16.542(3) A, beta = 105.584(15) degrees, and Z = 2. Compound 2 crystallizes in the monoclinic system, space group P2(1)/c, with a = 13.8097(8) A, b = 14.5765(4) A, c = 13.7853(15) A, beta = 96.033(9) degrees, and Z = 1. In compound 1 two copper ions are linked by two syn-syn acetates and two nonlinear NCN bridging groups pertaining to the deprotonated sulfamethazine ligands. Each copper center presents a nearly square planar geometry. Magnetic susceptibility data for 1 show a strong antiferromagnetic coupling with 2J = -216.7 cm(-)(1). The EPR spectra at the X- and Q-band frequencies present the signals corresponding to the dinuclear entity, being the zero-field splitting parameter, D = 0.265 cm(-)(1). The antiferromagnetic exchange coupling is discussed using DFT calculations on some model compounds with NCN bridging ligands and also on model structures with mixed mu-acetato and NCN bridges. The copper in the polymeric compound 2 is five coordinate. The CuN(5) chromophore has a highly distorted square pyramidal geometry with small axial N-Cu-N angles of 65.53(14) and 59.90(13) degrees. In the structure a sulfamethazinate anion binds to one copper through the sulfonamido and pyrimidine N atoms and to an adjacent copper via the amino N atom.

Journal Article↗