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A feeding trial was designed to examine the effects of copper sulfate pentahydrate (Cu[SO.sub.4] * 5[H.sub.2]O) on the fatty acid composition and oxidative stability in muscle and adipose tissues of Boer x Spanish goat kids. Fifteen (n = 5 per treatment) goats were fed 0, 100, or 200 mg of supplemental Cu per day as copper sulfate for 98 d. The animals were slaughtered, and LM, s.c. adipose from the sternal region, and mesenteric adipose tissues were collected. Total lipids were extracted with chloroform:methanol (2:1), methylated and isolated via GLC from all tissues. The subsequent peaks were then positively identified by mass spectrom etry. Thiobarbituric acid-reactive substances were measured also. In s.c. adipose, dietary Cu significantly decreased C14:0 (P = 0.03) and C16:0 (P = 0.01). In muscle, C15:0 (P = 0.03) was linearly increased by Cu. Dietary Cu supplementation did not influence oxidative stability in goat muscle or s.c. adipose. Copper supplementation at 200 mg/d resulted in a significant increase in malondialdehyde in mesenteric adipose (P = 0.01) compared with the 0 or 100 mg/d groups. These results indicate that lipid composition may differ from depot to depot and that depending on the depot, dietary Cu seems to elicit a variable response on the fatty acid composition. Key words: copper, diet, goat, lipid

There are conflicting data on the associations between copper and glycemia, plasma lipids, and atherosclerotic diseases. Copper has both pro-oxidant and antioxidant effects. We performed a cross-sectional analysis to investigate the associations between dietary copper intake and metabolic variables and serum high-sensitivity C-reactive protein (hs-CRP) in asymptomatic subjects from a population-based cohort (n = 1197) and between serum copper concentration and markers of oxidative stress, including plasma nitrotyrosine (NT) and total antioxidant status (TAS), hs-CRP, and metabolic variables in a subgroup of men from this cohort (n = 231). In all subjects, diastolic blood pressure and circulating glucose, uric acid, and total and LDL-cholesterol concentrations significantly decreased, whereas the hs-CRP concentration increased, from the lowest to the highest tertile of copper intake. In the male subgroup, glucose and total and LDL-cholesterol and TAS decreased, whereas hs-CRP and NT concentrations increased from the lowest to the highest tertile of serum copper concentration. In multiple regression models, dietary copper intake was inversely associated with diastolic blood pressure (P = 0.002), fasting glucose (P < 0.001), total cholesterol (P < 0.001), LDL-cholesterol (P < 0.001), and uric acid (P < 0.001) and was directly associated with the hs-CRP concentration (P < 0.001). Serum copper concentrations were inversely associated with glucose (P < 0.001), total cholesterol (P < 0.001), LDL-cholesterol (P < 0.001), and TAS (P < 0.001) and were directly associated with hs-CRP (P < 0.001) and NT concentrations (P < 0.001). Marginal copper deficiency is associated with an unfavorable metabolic pattern, but copper supplementation might not be recommended in view of its association with inflammation and markers of oxidative stress.

It is now widely accepted that abnormal prion proteins are the likely causative agent in bovine spongiform encephalopathy. Cellular prion proteins ([PrP.sup.c]) bind Cu, which appears to be required to maintain functional characteristics of the protein. The replacement of Cu on [PrP.sup.c] with Mn has resulted in loss of function and increased protease resistance. Twelve mature cows were used to determine the effects of Cu deficiency, alone and coupled with high dietary Mn, on brain Cu and Mn concentrations and on [PrP.sup.c] functional characteristics. Copper-adequate cows were randomly assigned to treatments: 1) control (adequate in Cu and Mn), 2) Cu-deficient (-Cu), and 3) Cu-deficient plus high dietary Mn (-Cu+Mn). Cows assigned to treatments -Cu and -Cu+Mn received no supplemental Cu and were supplemented with Mo to further induce Cu deficiency. After 360 d, Cu-deficient cows (-Cu and -Cu+Mn) tended to have lesser concentrations of Cu (P = 0.09) in the obex region of the brain stem. Brain Mn tended (P = 0.09) to be greater in -Cu+Mn cattle compared with -Cu cattle. Western blots revealed that [PrP.sup.c] relative optical densities, proteinase K degradability, elution profiles, molecular weights, and glycoform distributions were not different among treatments. The concentration of [PrP.sup.c], as determined by ELISA, was similar across treatment groups. Brain tissue (obex) Mn superoxide dismutase activity was greatest (P = 0.04) in cattle receiving -Cu+Mn, whereas immunopurified [PrP.sup.c] had similar superoxide dismutase-like activities among treatments. Immunopurified [PrP.sup.c] had similar Cu concentrations across treatments, whereas Mn was undetectable. We concluded that Cu deficiency, coupled with excessive Mn intake, in the bovine may decrease brain Cu and increase brain Mn. Copper deficiency, alone or coupled with high dietary Mn, did not cause detectable alterations in [PrP.sup.c] functional characteristics. Key words: bovine, copper, manganese, prion

Intracellular copper homeostasis in bacteria is maintained as the result of a complex ensemble of cellular processes that in Escherichia coli involve the coordinated action of two systems, cue and cus. In contrast, the pathogenic bacterium Salmonella harbours only the cue regulon, including copA, which is shown here to be transcriptionally controlled by CueR. Mutant strains in the CueR-regulated genes were constructed to characterize the response of Salmonella enterica serovar Typhimurium to high concentrations of extracellular copper under both aerobic and anaerobic conditions. Unlike its counterpart in E. coli, inactivation of cuiD displays the most severe phenotype and is also required for copper tolerance under anaerobic conditions. Deletion of copA has a mild effect in aerobiosis, but strongly impairs survival in the absence of oxygen. In a [DELTA]copA strain, a second Salmonella-specific P-type ATPase, GolT, can substitute the copper transporter, diminishing the effect of its deletion. The overall results highlight the importance of the cue system for controlling intracellular copper stress. The observed differences between Salmonella and E. coli in handling copper excess may contribute to our understanding of the distinct capability of these related pathogenic bacteria to survive outside the host.

Copper seems to be the schizophrenic metal, often thought of as very bad, and yet, very clearly recognized as necessary. Literally, a type of schizophrenia may be due to poor [...]