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PubMed1986

Influence of copper supplementation on blood and liver copper in cattle fed tall fescue or quackgrass.

Copper concentrations were measured in naturally Cu-deficient and Cu-supplemented yearling Hereford heifers fed tall fescue (Festuca arundinacea Schreb.) or quackgrass (Agropyron repens [L] Beauv.) forage. The data were used to establish a relationship between dietary Cu supplementation and accumulation of liver Cu, and to test the influence of diet and Cu supplementation on blood plasma Cu and ceruloplasmin oxidase activity. Dietary Cu supplementation was positively correlated with accumulation of liver Cu; the rate of increase in liver Cu levels diminished at high supplementation rates (liver Cu = 410.43 - 353.47 x e-.00295 x mg Cu supplement; R2 = .740), suggesting an efficient mechanism preventing fast, toxic Cu-overloading in cattle. The linear relationship (R2 = .7878) between blood plasma Cu and ceruloplasmin oxidase activity indicated that similar percentages of blood plasma Cu were present as ceruloplasmin in deficient, normal and Cu-supplemented cattle. However, the portion of plasma Cu occurring as ceruloplasmin changes significantly with type of feed. When compared with quackgrass, tall fescue not only produced rapid Cu depletion in unsupplemented cattle, but affected intermediary Cy metabolism and activity of Cu-enzyme ceruloplasmin differently at all levels of experimental Cu supplementation.

Animal Feed↗
PubMed1989

A laboratory study of the copper and nickel uptake and regulation in a copper-tolerant decapod, Cambarus bartoni (Fabricius) (Decapoda, Crustacea).

Tissue copper concentration in whole Cambarus bartoni, exposed for four weeks to 0.125, 0.25 and 0.5 mg Cu/litre and 0.2, 0.4 and 0.8 mg Ni/litre in the laboratory at 18 degrees C, showed a linear relationship with exposure time at 0.25 and 0.5 mg Cu/litre; the regression slope at 0.5 mg Cu/litre (r2 = 0.218; 0.001 less than P less than or equal to 0.05) was approximately two times higher than that at 0.25 mg Cu/litre (r2 = 0.148; 0.025 less than P less than or equal to 0.05). Regression analysis of nickel concentrations in whole crayfish as a function of exposure time showed a third degree polynomial relationship at 0.4 (y = 49.989 + 14.77x - 15.395x2 + 3.194x3) and 0.8 (y = 52.053 + 37.05x - 28.933x2 + 5.133x3) mg Ni/litre, as well as in the control (y = 49.126 + 27.253x - 23.468x2 + 4.168x3) (y = Ni concentration; x = exposure time in weeks), suggesting the occurrence of a Ni flux every 4 weeks.

Animals↗
PubMed2001

Copper status, serum cholesterol, and milk fatty acid profile in Holstein cows fed varying concentrations of copper.

An experiment was conducted to determine the effects of dietary copper (Cu) on Cu status and lipid metabolism in Holstein cows. Three primiparous and 21 multiparous Holstein cows were utilized in this experiment. Groups of three cows similar in parity, days in milk, and milk yield were assigned randomly to one of the following three treatments: 1) control (no supplemental Cu), 2) 10 mg of Cu/kg of DM from Cu sulfate (CuSO4), and 3) 40 mg of Cu/kg of DM from CuSO4. Liver Cu concentrations were higher in Cu supplemented cows at the end of the 61-d study. Cows receiving 40 mg of Cu/kg of DM had higher liver Cu concentrations than cows receiving 10 mg of Cu. Plasma Cu concentrations were similar across treatments. Total serum cholesterol concentrations were higher in cows receiving supplemental Cu. Cows receiving 40 mg of Cu/kg of DM had higher serum cholesterol concentrations than cows receiving 10 mg of Cu. Dry matter intake, average daily milk production, and milk lipid, protein, and somatic cell numbers were similar across treatments. On d 61, milk fatty acids C18:1 trans and C18-conjugated dienes were lower in cows receiving supplemental Cu relative to the nonsupplemented controls. Cows receiving 40 mg of Cu/kg of DM had higher C12:0 and lower C18:2 and total polyunsaturated fatty acids in milk than cows receiving 10 mg of Cu/kg of DM. These results indicate that Cu supplementation alters lipid metabolism in high producing dairy cows and that Cu supplementation at 40 mg/kg of DM for 61 d can elevate liver Cu concentrations to levels considered to be marginally toxic in dairy cattle.

Animals↗
PubMed1991

Effects of copper status on neutrophil function, superoxide dismutase, and copper distribution in steers.

Twelve Holstein steers in a completely randomized block design were fed either a basal diet (concentrate:silage or hay at a DM ratio of 35:65) plus Cu sulfate at 20 ppm of Cu (Cu-supplemented diet) or a basal diet plus ammonium molybdate to obtain 10 ppm of Mo (Cu-depleting diet) on a DM basis in the whole diet for 8 mo. Supplemental Mo was utilized in the Cu-depleting diet to develop a Cu-deficient group. Molybdenum slowly accumulated in the liver in the group fed the Cu-depleting diet. Copper concentrations in the liver and polymorphonuclear neutrophils decreased in the Cu-deficient group compared with the Cu-sufficient group. Plasma Cu concentration did not change during the trial for the Cu-sufficient group. In the Cu-deficient group, plasma Cu concentrations increased during the first 3 mo of the trial, then declined, and remained unchanged for the last 5 mo. Superoxide dismutase activities in red blood cells, polymorphonuclear neutrophils, and whole blood decreased in the Cu-deficient group. Phagocytic capacity was not affected by Cu status, but killing capacity was decreased by low Cu status in the Cu-deficient group by the end of the trial. Glutathione peroxidase activity was unaffected by Cu status. Clinical symptoms of Cu-deficiency were not observed in this trial; there was no evidence of blood hemoglobin or BW gain difference between the two groups. In this study, Cu status affected its distribution in the tissues and related enzyme activities as well as bactericidal function of neutrophils.

Animals↗
PubMed1992

Effects of copper supplementation on ceruloplasmin and copper-zinc superoxide dismutase in free-living rheumatoid arthritis patients.

Inflammation, an acute phase stress, alters copper (Cu) metabolism, but effects on human Cu requirements are unknown. Cu supplementation (2 mg/day, 4 weeks) increased erythrocyte Cu-zinc (Zn) superoxide dismutase (SOD) activity levels in 18 of 23 rheumatoid arthritis (RA) patients receiving gold or methotrexate (mean increase 21%). SOD values were significantly lower in RA patients than in 47 age- and sex-matched controls before, but not after supplementation. Supplementation did not significantly affect ceruloplasmin (Cp) activity or protein concentrations in either group. However, RA subjects showed significantly lower Cp activity to protein ratios compared to controls, before and after supplementation. Cu supplementation did not affect acute phase status of RA patients as evidenced by unchanged serum alpha-1-acid glycoprotein levels. In conclusion, the effects of Cu supplementation on erythrocyte SOD activities suggested a trend toward marginal Cu status in RA patients.

Adult↗
PubMed1991

Interactions between copper and selenium in sheep in the course of experimentally-produced copper intoxication.

This work evaluated the effect of interactions between copper (Cu) and selenium (Se) in the course of experimentally-produced Cu intoxication with industrial emissions on the animals' life spans and the Cu and Se concentrations in serum, liver and kidneys. We selected 15 Valaska ewes 1.5 y old. After the morning feeding all the animals were given emissions from a nearby Cu plant that contained 16.5% Cu and 0.0093% Se. Seven of the animals (group B) were given 5 ml SELEVIT injectable (Biotika, Slovenska Lupca)/head before starting the experiment and again on days 30 and 60. In the animals without Se supplementation (group A) the daily Cu and Se intakes from the emission and food were 466.0 mg and 2.56 mg, respectively. The average life span of the sheep in group A was 77 d and in group B it was 79.83 d. The first death due to intoxication occurred on the day 65 in group A and on day 69 in group B. During the emission feeding period no statistically significant differences were observed in cupraemia between the ewes with Se supplementation and those without it. Hypercupraemia was found in both groups from day 50 till death. Only at the end of the experiment was the serum Cu of group A statistically lower than that in group B. Cu concentrations in the liver and kidneys (dry matter) of the sheep that died with Cu intoxication in group A was 2138 +/- 1090.96 mg/kg and 272.94 +/- 197.16 mg/kg, and in group B they were 2603 +/- 1332.9 mg/kg and 341.65 +/- 307.45 mg/kg, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollutants, Occupational↗
PubMed1988

Use of 2,3,2-tetramine as a hepatic copper chelating agent for treatment of copper hepatotoxicosis in Bedlington terriers.

Five Bedlington Terriers with inherited copper (Cu) hepatotoxicosis and with hepatic Cu concentrations ranging from 3,000 to 11,000 micrograms/g of dry weight (normal, less than 350 micrograms/g of dry weight) were treated daily for up to 200 days with 2,3,2-tetramine tetrahydrochloride. During treatment, no change was made in the dietary Cu intake, which ranged from 12 to 16 micrograms/g of dry diet. Concentrations of hepatic and serum Cu, iron, and zinc were determined before and at the conclusion of the treatment period. In one dog, 24-hour urinary Cu concentration was measured before and during treatment. A liver biopsy specimen obtained after treatment had significantly (P less than 0.05) reduced hepatic Cu concentration (3,282 micrograms/g of dry weight; a 54.9% reduction), compared with the pretreatment value (7,281 micrograms/g of dry weight). After treatment, there was an overall general lessening of the extent of hepatic morphologic damage. Cytochemical examination for Cu in rhodanine-stained biopsy specimens revealed decreased numbers of Cu-laden hepatic lysosomes. The mean daily urinary Cu concentration increased as much as 25-fold during 2,3,2-tetramine treatment. Hepatic iron and zinc concentrations and serum Cu concentrations remained within normal ranges after treatment. Clinical or laboratory evidence of 2,3,2-tetramine toxicosis was not detected during treatment. These findings indicated that in affected Bedlington Terriers, 2,3,2-tetramine was a safe and rapid chelating agent of hepatic Cu.

Animals↗
PubMed1981

Protections by non-copper metal ions against copper-mediated inactivation of poliovirion RNA occurring at extraction of virions with phenol.

Al3+, Ca2+, Co2+, Cu1+, Fe2+, Fe3+, Mg2+, Mn2+, Ni2+, Pb2+, Sn4+, and Zn2+ were incubated individually with redistilled reagent-grade phenol containing impurities known from previous work to interact with Cu2+ to produce a potent inactivator(s) of the transfectivity of naked poliovirion RNA. Only the mixture with Cu1+ inactivated the RNA. Tests of each of the 11 non-copper test metal ions mixed with Cu2+ before adding the phenol showed that Ca2+ and Mg2+ do not protect, Co2+, Mn2+, Ni2+, Pb2+, and Zn2+ provide moderate protection, and Al3+, Fe2+, Fe3+, and Sn4+ give strong protection against the Cu2+-mediated inactivation. Other points of addition of protective metal ion were tested using Fe3+. Strong protection was afforded even when Fe3+ was added after synthesis of the inactivator(s) from Cu2+ and the active impurities. The relation between Cu2+ and the Fe3+ was shown to be competitive. The hypothesis that ions compete for semi-quinone anion is proposed.

Copper↗
PubMed1996

Dosimetric evaluation of copper-64 in copper-67-2IT-BAT-Lym-1 for radioimmunotherapy.

UNLABELLED: Copper-67 (67Cu) is an attractive radionuclide for radioimmuno-therapy because of its favorable physical and biologic characteristics. Current supplies of 67Cu, however, contain as much as 60% of 64Cu at the time of delivery. Scatter photons from 64Cu enter the 67Cu energy window, affecting image resolution and counting accuracy. The radiation dose to tissue is also altered. METHODS: A line source and a small vial source of 67Cu containing varying amounts of 64Cu were used to evaluate the impact of 64Cu on image resolution and activity quantitation, respectively. Identical pharmacokinetics for 67Cu and 64Cu was assumed, and the radiation dosimetry of 64Cu was assessed using quantitative imaging data for 67Cu because the amount of 64Cu could be calculated for any time after 67Cu production. MIRD formalism was used to estimate the therapeutic index, defined as the ratio of radiation dose to tumor divided by the radiation dose to bone marrow. RESULTS: As the amount of 64Cu increased, the full width at tenth maximum of the line spread function increased, although there was no significant change in full width at half maximum. The number of scatter counts from 64Cu increased as the amount of 64Cu or the size of the source region of interest increased. When 64Cu was 25% of the total activity, less than 10% of the total 67Cu photopeak counts detected with a scintillation camera were attributable to 64Cu. Although the tumor radiation dose per unit of activity (cGy/GBq) from 67Cu was five times greater than that from 64Cu, the marrow dose (CGy/GBq) from 67Cu was only three times greater than that from 64Cu. Therefore, the therapeutic index was diminished by the presence of 64Cu. When 64Cu radioimpurity was less than 25% of the total activity, there was less than a 10% decrease in the therapeutic index. CONCLUSION: The shorter physical half-life of 64Cu relative to that of 67Cu and slower uptake and longer retention of antibody by tumor than by marrow result in a lower therapeutic index for 64Cu. The 25% radioimpurity of 64Cu causes less than 10% deviation in activity quantitation and diminution in the therapeutic index. The change in therapeutic index is predictable over time and can be used to determine the optimal time for radiopharmaceutical administration.

Bone Marrow↗
PubMed2003

Investigation of protonatable residues in Rhodothermus marinus caa3 haem-copper oxygen reductase: comparison with Paracoccus denitrificans aa3 haem-copper oxygen reductase.

The Rhodothermus marinus caa(3 )haem-copper oxygen reductase contains all the residues of the so-called D- and K-proton channels, with the notable exception of the helix VI glutamate residue (Glu278(I) in Paracoccus denitrificans aa(3)), being nevertheless a true oxygen reductase reducing O(2) to water, and an efficient proton pump. Instead, in the same helix, but one turn below, it has a tyrosine residue (Tyr256(I), R. marinus caa(3) numbering), whose hydroxyl group occupies the same spatial position as the carboxylate group of Glu278(I), as deduced by comparative modelling techniques. Therefore, we proposed previously that this tyrosine residue could play an important role in the proton pathway. In this article we further study this hypothesis, by investigating the equilibrium thermodynamics of protonation in R. marinus caa(3), using theoretical methodologies based on the structural model previously obtained. Control calculations are also performed for the P. denitrificans aa(3) oxygen reductase. In both oxygen reductases we find several residues that are proton active (i.e., that display partial protonation) at physiological pH, some of them being redox sensitive (i.e., sensitive to the protein redox state). However, the caa(3 )Tyr256(I) is not proton active at physiological pH, in contrast to the aa(3) Glu278(I) which is both proton active at physiological pH and shows a high redox sensitivity. In R. marinus caa(3) we do not find any other residues in the same protein zone that can have this property. Therefore, there are no putative D-channel residues that are proton active in this oxidase. The protonatable residues of the K-channel are much more functionally conserved in both oxygen reductases than the same type of residues in the D-channel. Two (Tyr262(I) and Lys336(I), caa(3) numbering) out of three protonatable K-channel residues are proton active and redox sensitive in both proteins.

Amino Acids↗
PubMed1983

Blue copper sites and analogous sites in copper-containing oxidases: a structural description.

The secondary structure of the C-terminal region of all blue copper proteins can be assigned to two beta strands and a connecting segment that contains a potential histidine ligand. A similar assignment is made for the second probable blue (Type 1) site that is located in the middle fragment of ceruloplasmin also. The secondary structure regions for stellacyanin and subunit II of cytochrome oxidase predicted by the Chou-Fasman method are compared to those found in the crystal structures of plastocyanin and azurin.

Azurin↗
PubMed1987

A potential copper radiopharmaceutical for imaging the heart and brain: copper-labeled pyruvaldehyde bis(N4-methylthiosemicarbazone).

An investigation of the biodistribution of lipophilic copper-64 (half-life = 12.7 h) compounds has been initiated in order to screen potential tracers that could be used to measure regional cerebral and/or myocardial blood flow when labeled with generator-produced 62Cu. The 64Cu complex of pyruvaldehyde bis(N4-methylthiosemicarbazone), [64Cu]Cu-PTSM, was prepared and found to be lipophlic (octanol/saline partition coefficient, log p = 1.97 +/- 0.03). Biodistribution studies following i.v. injection of [64Cu]Cu-PTSM into rats show tracer uptake by the brain and heart. At 1, 5, and 15 min post-injection 3.3, 3.0 and 2.7% of the injected dose was found in the brain. Corresponding brain to blood ratios (per gram) were 3.2, 3.6 and 4.0 respectively. Heart to blood ratios of 7.6, 7.6 and 7.3 were observed at these same time points.

Animals↗
PubMed2001

Effects of high copper supplements on performance, health, plasma copper and enzymes in goats.

Six growing female Nubian goats (average BW=34.8+/-0.55kg, 7-8 months of age) were randomly assigned to either a basal diet (BD, 10-15ppm Cu/DM), or to medium Cu (MC, BD+50mgCu), or to high Cu (HC, BD+100mgCu) diets for 9 weeks. This level would cause Cu toxicity in sheep, but none occurred in the goats. Therefore, Cu supplementation was then increased to 150 and 300mg per head per day, for the following 14 weeks; to 300 and 600mg per head per day, for the next 8 weeks; and to 600 and 1200mg per head per day, for an additional 4 weeks, in the MC and HC group, respectively. Body weight and vital signs were recorded and blood samples collected at different time intervals. Hematological parameters, plasma Cu, sorbitol dehydrogenase (SDH), glutamic oxaloacetic transaminase (GOT), and gamma-glutamyl transferase (GGT) were determined. At the termination of the study, tissue Cu concentration in different organs was also determined. During first 23 weeks (<300mgCu per day) of the study there were no apparent signs of Cu toxicity. Cu supplementation at 600mg per head per day in young Nubian does, had no effect on respiration rate (RR), heart rate (HR), and decreased (P<0.05) rectal temperature (RT) in the HC group only. Leukocyte counts were positively correlated with Cu supplementation (r=+0.296, P<0.02) and negatively correlated (r=-0.254, P<0.05) with RT in the HC group. Plasma SDH increased (P<0.05) when Cu supplementation was >/=300mg per head per day, thus, SDH may serve as an early indicator of Cu toxicosis in goats. Increases (P<0.05) in GOT were noted when Cu intake was >/=600mg per head per day. Contrary to the results observed for SDH and GOT, feeding goats 50mgCu per day or more, resulted in an increased plasma GGT as compared to BD goats. Levels of SDH, GOT and GGT of the BD goats were within normal range. Plasma Cu was not indicative of Cu status of animals. Copper improved ADG by 28% at the 100-150ppm level in diet. No relationship between Cu intake and hair Cu was found in the present study. Highest concentration of Cu was found in liver, followed by duodenum, rumen and brain. Results of this study indicate that goats are more resistant to Cu toxicity than sheep. This is one of the first reports documenting significant differences in Cu requirements and tolerance between goats and sheep.

Journal Article↗
PubMed2001

Crossover phase behavior (discotic to calamitic) in liquid-crystalline copper complexes. Dependence on the length and position of alkoxy chains in new polycatenar bis[5-(dialkoxybenzylidine)aminotropololonato]copper(II) complexes.

New polycatenar metallomesogens have been synthesized containing a tropolone core joined to benzylidine terminal rings. Variation of the position, number, and nature of alkoxy substituents on the terminal rings allows for the control of the phase behavior of the compounds. In particular, for copper complexes with 3,4-dialkoxy substitution, a change from calamitic to discotic (columnar) behavior is seen as the chain lengths are increased.

Journal Article↗
PubMed2001

The contribution of ligand flexibility to metal center geometry modulated thermal cyclization of conjugated pyridine and quinoline metalloenediynes of copper(I) and copper(II).

We report the syntheses, reactivities, and structure evaluations of a series of Cu(I) and Cu(II) metalloenediynes of conjugated 1,6-bis(pyridine-3)hex-3-ene-1,5-diyne (PyED, 7) and 1,6-bis(quinoline-3)hex-3-ene-1,5-diyne (QnED, 8) enediyne ligands, as well as their benzoenediyne analogues. Differential scanning calorimetry demonstrates that the [Cu(PyED)(2)](NO(3))(2) (11) exhibits a Bergman cyclization temperature (156 degrees C) which is dramatically reduced from that of the corresponding [Cu(PyED)(2)](PF(6)) (19) analogue (326 degrees C), indicating that large differences in the reactivities of these metalloenediynes can be accessed by variations in metal oxidation state. The distorted, 4-coordinate dichloride compound Cu(PyED)(Cl)(2) (15) exhibits a cyclization temperature (265 degrees C) between those of 11 and 19, suggesting that variation in geometry of the copper center is responsible for the wide range of reactivities. Similar results are obtained for the benzoenediyne and quinoline analogues. The structures of the Cu(II) systems have also been evaluated by a combination of electronic absorption and EPR spectroscopies which reveal tetragonal, 6-coordinate structures for the bis(enediyne) complexes, and tetrahedrally distorted 4-coordinate Cu(enediyne)Cl(2) species. For the bis(quinoline) enediyne derivatives 12 and 14 the larger g-anisotropy (g( parallel) = 2.27-2.28; g( perpendicular) = 2.06-2.07) indicates strong oxygen coordination from counterion. Molecular mechanics/dynamics calculations reveal that the geometries of these metal centers force the alkyne termini to a wide range of distances (3.85-4.20 A), thereby accounting for the variability in Bergman cyclization temperatures. Overall, the results show that ligand rigidity plays a prominent role in the conformational response of the enediyne to metal center geometry, which results in enhanced variations in the Bergman cyclization temperatures between complexes of different geometries.

Journal Article↗
PubMed2001

Formation study and X-ray structures of dinuclear beta-diketonate copper(I) complexes with conjugated ene-yne Lewis base. Implications for the use of (hfac)Cu(MHY) as a precursor for copper CVD.

Dinuclear [(hfac)Cu](2)(MHY) and [(hfac)Cu](2)(HY) species, where hfac = hexafluoroacetylacetonate, MHY = 2-methyl-1-hexen-3-yne, and HY = hex-3-yn-1-ene), are formed during copper chemical vapor deposition experiments when a bubbler containing the corresponding mononuclear species is used. These compounds and the so far unknown (hfac)Cu(HY) have been characterized by (1)H and (13)C NMR and IR spectroscopy and the two dinuclear species by X-ray crystallography and elemental analysis. As expected, in the structure of the dinuclear species, two roughly perpendicular Cu(hfac) moieties are bound to a single ene-yne: one to the C[triple bond]C, the other to the conjuguated double bond. Weak intra- and intermolecular Cu...Cu interactions have been detected in the solid. [(hfac)Cu](2)(HY) is more stable and more easily formed than [(hfac)Cu](2)(MHY) because of the hindrance character of the additional methyl groups. The formation of the dinuclear species from the mononuclear species is reversible as it has been demonstrated by (1)H NMR. The mononuclear species can be recovered from the dinuclear species when free ene-yne base is added. Crystallographic data for [(hfac)Cu](2)(MHY): C(17)H(12)O(4)F(12)Cu(2), triclinic, P1 (No. 2), Z = 4; at 298 K, a = 11.112(3) A, b = 13.472(4) A, c = 15.747(3) A, alpha = 94.95(2) degrees, beta = 98.15(2) degrees, gamma = 100.27(2) degrees; Crystallographic data for [(hfac)Cu](2)(HY): C(16)H(10)O(4)F(12)Cu(2), orthorhombic, Cc2a (No. 41, Aba2), Z = 8; at 230 K, a = 12.280(3) A, b = 13.531(3) A, c = 25.461(5) A.

Journal Article↗