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1.
Vitamin E and selenium (SE) are essential nutrients that are integral components of the antioxidant defense of tissues and cells. Soils in many of the important dairy regions of the world are Se-deficient, and feedstuffs grown on these soils will not provide adequate dietary Se. Cattle consuming stored forages are likely to be low in vitamin E unless supplemented, and vitamin E deficiencies are frequently observed in peripartum dairy cows. Many new intramammary infections (IMI) occur in the 2 wk before and after calving. Deficiencies of either vitamin E or Se have been associated with increased incidence and severity of IMI, increased clinical mastitis cases, and higher somatic cell counts (SCC) in individual cows and bulk tank milk. Somatic cell counts are a primary indicator of mastitis and milk quality in dairy herds. The polymorphonuclear neutrophil (PMN) is a major defensive mechanism against infection in the bovine mammary gland. A know consequence of vitamin E and Se deficiency is impaired PMN activity and postpartum vitamin E deficiencies are frequently observed in dairy cows. Dietary supplementation of cows with Se and vitamin E results in a more rapid PMN influx into milk following intramammary bacterial challenge and increased intracellular kill of ingested bacteria by PMN. Subcutaneous injections of vitamin E approximately 10 and 5 d before calving successfully elevated PMN alpha-tocopherol concentrations during the periparturient period and negated the suppressed intracellular kill of bacteria by PMN that commonly is observed around calving.  相似文献   

2.
The relationship between atherosclerosis and fat soluble vitamin, especially vitamin E is reviewed on the basis of oxidised modification of low density lipoprotein (LDL). Data now support the notion that the oxidised LDL is present in the blood and arterial wall and antioxidant drugs such as probucol and vitamin E, beta-carotene, may prevent the progression of atherosclerosis. LDL alpha-tocopherol levels are generally correlated to the plasma concentrations and supplementation with alpha-tocopherol increases its content in LDL. There is a significant correlation between the LDL alpha-tocopherol level and the resistance to oxidative modification. Epidemiological data also shows the relation between low levels of plasma vitamin E and the increased incidence of coronary heart disease. Clinical application of vitamin E should be clarified in detail to inhibit the progression of atherosclerosis.  相似文献   

3.
Supplementation of selenium and vitamin E to enhance disease resistance in dairy cattle has become common, particularly to prevent periparturient reproductive disorders and mastitis. To establish reference values for serum vitamin E and selenium concentrations in postparturient dairy cattle and to determine whether serum concentrations of these micronutrients varied with season and stage of lactation, cows from a stratified random sample of 50 herds were studied for 1 year. Blood samples were collected from each of the 50 study herds twice, from the 10 most recently parturient cows or from 10% of the herd, whichever was greatest. Mean concentration of vitamin E and selenium was 2.55 micrograms/ml and 78.12 ng/ml, respectively. Vitamin E concentrations were significantly (P < 0.05) higher during the summer and fall than during the winter and spring. Selenium concentrations were significantly (P < 0.05) lower during the summer and fall than during the winter and spring. Herd, season of blood sample collection, and time since parturition were significant (P < 0.02) in explaining variation in vitamin E and selenium concentrations.  相似文献   

4.
Five groups of winter-housed cows (n = 10 per group) that calved in the winter were used to assess the effect of beta-carotene supplementation on postpartum reproductive performance. Near parturition and immediately after calving the beta-carotene concentrations of the blood plasma were decreased and no differences could be found between the control and the supplemented groups. The results obtained at postpartum day 60 suggest that supplementation of the daily winter ration with 300 mg of synthetic beta-carotene with or without vitamins A, D3 and E exerts the most favourable effect on reproduction, as judged not only from B-carotene and vitamin A contents of the blood plasma, colostrum and milk but also from the improved fertility indices. The number of inseminations per cow was reduced and the conception rate was significantly higher in cows supplied additionally with 300 mg of synthetic beta-carotene with or without vitamins A, D3 and E. It can be concluded that beta-carotene is an important factor in bovine reproduction and that its specific role cannot be taken over by vitamin A.  相似文献   

5.
We conducted an experiment for 112 d with yearling beef heifers to evaluate the effects of cottonseed meal (CSM) fed with various concentrations of vitamin E on hematological and tissue components. Heifers were assigned randomly to four treatments, with eight heifers per treatment. The treatments consisted of the following dietary supplements: 1) CON, based on soybean meal with 30 IU vitamin E/kg; 2) GOS, based on CSM with 30 IU vitamin E/kg; 3) G+2E, based on CSM with 2,000 IU vitamin E x animal(-1) x d(-1); and 4) G+4E, based on CSM with 4,000 IU vitamin E x animal(-1) x d(-1). Supplements based on CSM provided 4.5 g of free and 50.5 g of total gossypol x animal(-1) x d(-1). The total gossypol present in the supplements was 29.1% of the negative isomer (-) and 70.9% of the positive isomer (+). Blood samples were collected at the start of the experiment and every 2 wk thereafter up to 16 wk. There was a time x treatment interaction (P<.01) for plasma alpha-tocopherol ( alpha-T) concentration; however, feeding gossypol did not decrease plasma alpha-T. Weight gain, retinol palmitate, retinol, beta-carotene (beta-C), hemoglobin, and hematocrit were not affected by treatment. Erythrocyte osmotic fragility (EOF) increased (P<.05) in gossypol-fed animals; however, vitamin E supplementation lowered EOF (P<.05). Heifers fed the supplements GOS, G+2E, and G+4E had greater (P<.01) plasma (-)-, (+)-, and total gossypol than heifers fed CON from Collection 2 to the end of the experiment. There was a treatment effect (P<.05) on vitamin E and gossypol concentrations in different tissues, with no effect (P>.05) for trace minerals (Cu, Zn, Fe, and Se). Vitamin E concentration in tissue increased with increased dietary supplementation of vitamin E. In heart and neck muscle, (-)-gossypol was greater (P<.05) than (+)-gossypol, but the reverse was true for liver. Gossypol decreased in vitro lipid peroxidation of liver homogenate in tissues. Gossypol deposition in tissue was liver > heart > muscle. In summary, gossypol from CSM did not decrease concentrations of antioxidant vitamins, including alpha-T, vitamin A, and beta-C, or have any detrimental effect on performance of beef heifers.  相似文献   

6.
SETTING: Inflammation-related oxidative stress has been implicated in the pathogenesis of lung fibrosis and dysfunction in patients with pulmonary tuberculosis. OBJECTIVE: To investigate the effects of antimicrobial chemotherapy and smoking status on the plasma concentrations of the anti-oxidative nutrients vitamin C, vitamin E and beta-carotene, as well as those of iron, lipid peroxides and the acute phase reactants C-reactive protein (CRP) and ferritin. DESIGN: A total of 41 patients with active pulmonary tuberculosis were studied at the outset and after 6 months of antimicrobial chemotherapy. RESULTS: Initial plasma concentrations of vitamin C and beta-carotene were low, returning to normal values after chemotherapy in the non-smokers, but not in the smokers, while those of vitamin E remained low throughout in both groups. Ferritin and CRP concentrations decreased significantly following chemotherapy, with the former higher in smokers than in non-smokers. Serum lipid peroxides were elevated in patients with pulmonary tuberculosis and were unaffected by chemotherapy or smoking habits, while iron levels were not significantly affected by chemotherapy. Although residual dysfunction and infiltration were evident, pulmonary function (FEV1) and radiographic score improved equally in both smokers and non-smokers following antimicrobial chemotherapy. CONCLUSIONS: Even after 6 months of apparently successful antimicrobial chemotherapy, pulmonary tuberculosis is associated with increased oxidative stress, which is unrelated to cigarette smoking and characterized by increased levels of circulating lipid peroxides and low concentrations of plasma vitamin E.  相似文献   

7.
The aim of this randomized study was to examine changes in vitamin E concentration in female subjects (age 30-60, ASA I) after cholecystectomy and halothane (N = 16) or isoflurane (N = 16) anaesthesia. Vitamin E concentration was measured two days before, and then one, five and twenty-four hours and four days after surgery. High-pressure liquid chromatography was used for its determination. Simultaneously activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyltransferase (GGT) were determined. Statistical analysis: ANOVA, Tukay HSD test. The research has been accepted by the Drugs Committee of the Karlovac County Hospital. Preoperative vitamin E concentrations in the halothane group were 8.69 +/- 2.35 micrograms/L, median 8.67 micrograms/L and in the isoflurane group 9.43 +/- 2.4 micrograms/L, median 9.08 micrograms/L. Statistically lower vitamin E concentrations compared with preoperative values were noted one hour (P < 0.05), 5 hours (P < 0.01), 24 hours (P < 0.01), as well as 4 days (P < 0.01) after the operation. The lowest vitamin E concentrations were noted 24 hours after the operation with statistically insignificantly higher values in the isoflurane group (halothane group 5.98 +/- 2.08 micrograms/L, isoflurane group 6.58 +/- 1.51 micrograms/L). Analyzing enzyme (ALT, AST and GGT) pre- and postoperative values, no statistically significant differences between the investigated groups and during the time were observed. Statistically significant differences were found between individual measurement times, with no statistical significance of the differences between the halothane and isoflurane groups. It seems that neither the difference in halothane and isoflurane biotransformation nor their distinct effect on perfusion of some organs are the determining factors in post-operative changes in vitamin E concentration.  相似文献   

8.
Paediatric reference intervals for blood concentrations of certain nutrients are often based on either adult data or are derived from small samples of young children. Biochemical data were obtained from 467 randomly selected, healthy preschool children aged 9-62 months in Sydney, Australia. Data were obtained for plasma vitamins A, E and beta-carotene and for serum zinc, retinol-binding protein and prealbumin. Reference intervals based on the 2.5 and 97.5 centiles for age groups 9-23, 24-35, 36-47, 48-62 months and for the total group (9-62 months) were calculated. The 2.5-97.5 centiles for the whole group were: vitamin A, 0.7-1.8 mumol/l (20.05-51.56 micrograms/dl); vitamin E, 8-30 mumol/l (0.34-1.29 mg/dl); beta-carotene, 0.1-1.1 mumol/l (5.4-59.0 micrograms/dl); zinc, 9-19 mumol/l (58.8-124.2 micrograms/dl); retinol-binding protein, 14-36 mg/l; prealbumin, 104-264 mg/l. The reference intervals reported are consistent with the findings of a number of smaller studies and are likely to be an accurate reflection of the true intervals for healthy preschool children in western developed countries.  相似文献   

9.
Vitamin C status and possible associations with the disease process in cystic fibrosis (CF) patients were investigated. Plasma vitamin C concentrations in patients from two different mid-European populations (Swiss, n = 62; Austrian, n = 60) taking no or low-dose vitamin C from multivitamin supplements did not differ from each other or from control subjects (n = 34). Vitamin C concentrations decreased with age (5.05 mumol.L-1, y-1). When followed up for 12 mo, patients had the highest plasma vitamin C concentrations in February and the lowest in May and August (P < 0.01); the decrease in vitamin C was accompanied by increases in plasma malondialdehyde (P < 0.001) and tumor necrosis factor alpha concentrations (P < 0.01). During supplementation with vitamin E for 2 mo or beta-carotene for 12 mo vitamin C concentrations did not change. They correlated inversely with white blood cell count (r = -0.36, P = 0.008), bands (r = -0.36, P = 0.02), alpha 1-acid glycoprotein (r = -0.45, P = 0.002), interleukin 6 (r = -0.46, P = 0.0006), and neutrophil elastase/alpha 1-proteinase inhibitor complexes (r = -0.34, P = 0.02). In patients with vitamin C concentrations < 40 mumol/L, all indexes of inflammation were relatively high, whereas those with concentrations > 80 mumol/L (upper quartile of control subjects) showed clearly lower values. These results are consistent with the hypothesis that by scavenging oxygen free radicals vitamin C interacts with an inflammation-amplifying cycle of activation of alveolar macrophages and neutrophils, release of proinflammatory cytokines and oxygen free radicals, and inactivation of antiproteases.  相似文献   

10.
We tested the hypothesis that the incidence of retained fetal membranes could be reduced by limiting oxidative stress. Sixty-four primigravid heifers (56 Holstein and 8 Jersey) and 80 multiparous cows (64 Holstein and 16 Jersey) were used. A combination of vitamin E or Zn and Fe was fed in a 2 x 2 x 2 factorial arrangement during the last 42 d prepartum. Amounts of supplements per animal were 1000 IU of vitamin E (d, l alpha-tocopheryl acetate), 0.8 g of Zn (Zn-Met and ZnSO4), and 12 g of Fe (FeSO4.7H2O) for Holsteins and 9 g for Jerseys. Neither vitamin E nor Zn directly affected the incidence of retained fetal membranes, but plasma alpha-tocopherol was lower when fetal membranes were retained > 12 h or when vitamin E was not supplemented. Iron had no direct negative effects on reproductive performance, but cows receiving additional Fe had lower unsaturated iron-binding capacity, which, in turn, was also lower in cows that retained fetal membranes. Days to first observed estrus were reduced by supplementation with either vitamin E or Zn. Vitamin E reduced days to first artificial insemination (AI) and tended to reduce days open. Supplemental Zn tended to reduce days to first AI but did not affect days open. Milk production during the first 12 wk and AI per conception were not affected by supplementation with either vitamin E or Zn. Both vitamin E and Zn reduced days to first observed estrus, indicating improved reproductive health during the early postpartum period.  相似文献   

11.
The phospholipids of avian spermatozoa are characterized by high proportions of arachidonic (20:4n-6) and docosatetraenoic (22:4n-6) fatty acids and are therefore sensitive to lipid peroxidation. Alpha-tocopherol and glutathione peroxidase [GSH-Px] are believed to be the primary components of the antioxidant system of the spermatozoa. The present study evaluates the effect of vitamin E and vitamin E plus Se supplementation of the cockerel diet on GSH-Px activity, vitamin E accumulation, and lipid peroxidation in the spermatozoa, testes, and liver. At the beginning of the experiment 75 Rhode Island Red cockerels were divided into five groups, kept in individual cages, and fed a wheat-barley-based ration balanced in all nutrients. Supplements fed to the different groups were as follows: vitamin E, 0, 20, 200, 20, and 200 mg/kg to groups 1-5, respectively, with groups 4 and 5 also receiving 0. 3 mg Se/kg. The vitamin E supplementation produced increased levels of alpha-tocopherol in semen, testes, and liver. The inclusion of the Se into the cock diet had a significant (P < 0.01) stimulating effect on GSH-Px activity in seminal plasma, spermatozoa, testes, and liver. The increased vitamin E concentration in the spermatozoa was associated with a reduction in their susceptibility to lipid peroxidation. Similarly, the increased GSH-Px activity provided enhanced protection against lipid peroxidation.  相似文献   

12.
A study was conducted to evaluate the effects of high dietary vitamin A on vitamin E status and performance of growing-finishing pigs fed diets supplemented with varying levels of vitamin E. Treatments consisted of corn-soybean meal-based diets supplemented with retinyl acetate to provide 2,000 or 20,000 IU of vitamin A/kg of diet and with DL-alpha-tocopheryl acetate to provide 0, 15, or 150 IU of added vitamin E/kg in a 2 x 3 factorial arrangement. The trial involved 84 crossbred pigs (26 kg initial BW) allotted to pens of two pigs each (one gilt, one barrow). Serum was obtained from all pigs on d 0, 3, 7, 21, 35, 63, and 77 of the 83- or 90-d feeding period. Tissue samples (liver, leg, and neck muscle, backfat, and leaf fat) were collected from one pig (barrow) in each pen at the end of the feeding period. Average daily gain and gain:feed were .93 kg and .30, respectively, without treatment differences (P > .10). Serum alpha-tocopherol increased linearly (P < .01) by d 3 with increasing level of dietary vitamin E supplementation. High dietary vitamin A resulted in a small decrease (P < .01) in serum alpha-tocopherol on d 3, but serum alpha-tocopherol concentration was not affected (P > .10) on other days. Tissue alpha-tocopherol increased linearly (P < .001) as dietary vitamin E increased in all tissues examined. No consistent evidence was found to indicate that a high level of dietary vitamin A interfered with performance or with blood serum or tissue alpha-tocopherol concentrations in growing-finishing swine.  相似文献   

13.
Beginning at hatching, chicks were fed a Basal diet, without vitamin E or selenium (Se) or the same diet supplemented with vitamin E (100 IU/kg) and Se (0.2 ppm). The effect of these treatments on the expression of cell surface markers (CT-1a, CD3, CD4, CD8, sIgs, and Ia) defining specific thymocyte and peripheral blood leukocyte (PBL) subpopulations were examined using flow cytometric analyses. In parallel studies the effect of the dietary deficiencies on splenocyte proliferative responses to ConA or PHA stimulation was examined. The mean expression of CD3 and CT-1a per cell was increased while CD8 and CD4 expression was decreased on thymocytes from chicks fed the Basal diet. The proportion of double negative (CD4-, CD8-) thymocytes and single positive CD8+ thymocytes was significantly decreased while single positive CD4+ and double positive (CD4+, CD8+) thymocytes were significantly increased by the dietary vitamin E and Se deficiencies. The dietary deficiencies resulted in a decreased proportion of peripheral T cells and specifically decreased the number of CD4+ PBL. The proliferative response to both ConA and PHA was impaired by the vitamin E and Se dietary deficiencies. The proliferative response could be fully reconstituted but only after vitamin E and Se supplementation for periods longer than 1 week. Plasma SeGSHpx and alpha-tocopherol levels paralleled the mitogen responsiveness observed. These results support the conclusion that vitamin E and Se deficiencies may affect both the maturation of specific lymphocyte subpopulations and the functional and proliferative capabilities of the peripheral lymphocytes.  相似文献   

14.
BACKGROUND: Epidemiologic studies have shown dietary antioxidants to be inversely correlated with ischemic heart disease. OBJECTIVE: We investigated whether dietary beta-carotene, vitamin C, and vitamin E were related to the risk of myocardial infarction (MI) in an elderly population. DESIGN: The study sample consisted of 4802 participants of the Rotterdam Study aged 55-95 y who were free of MI at baseline and for whom dietary data assessed by a semiquantitative food frequency questionnaire were available. During a 4-y follow-up period, 124 subjects had an MI. The association between energy-adjusted beta-carotene, vitamin C, and vitamin E intakes and risk of MI was examined by multivariate logistic regression. RESULTS: Risk of MI for the highest compared with the lowest tertile of beta-carotene intake was 0.55 (95% CI: 0.34, 0.83; P for trend = 0.013), adjusted for age, sex, body mass index, pack-years, income, education, alcohol intake, energy-adjusted intakes of vitamin C and E, and use of antioxidative vitamin supplements. When beta-carotene intakes from supplements were considered, the inverse relation with risk of MI was slightly more pronounced. Stratification by smoking status indicated that the association was most evident in current and former smokers. No association with risk of MI was observed for dietary vitamin C and vitamin E. CONCLUSION: The results of this observational study in the elderly population of the Rotterdam Study support the hypothesis that high dietary beta-carotene intakes may protect against cardiovascular disease. We did not observe an association between vitamin C or vitamin E and MI.  相似文献   

15.
Lysosubtilin is a broad-spectrum preparation of lytic enzymes from Bacillus subtilis designed for veterinary medicine. This study demonstrates its efficacy for the treatment of reproductive system diseases (mastitis, superficial lesions of the udder and teats) in cows. Prior to determination of optimal therapeutic doses, samples taken from the milk and udder skin of sick animals were examined microbiologically. The examinations revealed a high incidence of polymicrobial infections (26.9 and 84.9% for mastitis and superficial udder lesions, respectively) caused by various mixtures of bacteria (both Gram-positive and Gram-negative) and fungi/yeasts. Dose determination studies involved 115 cows with clinical signs of mastitis. The optimal dose for mastitis treatment was found to be 3.5 x 10(6) U lysosubtilin dissolved in 100 mL of distilled water, which was then administered into the mammary gland via the teat canal once daily until recovery. Such a dose yielded statistically significant decreases (P < 0.05) both in the length of time before clinical recovery (2 d versus 4 and 4.5 d with either of the two antibiotic-based traditional drugs) and in the percentage of animals who suffered relapses within a 2-month period following treatment (5% versus 60%, with one of the two drugs). A field experiment involving 106 cows was designed to compare the efficacy of 1% lysosubtilin water-glycerin solution (1:9 v/v) and other traditional medications for the topical treatment of superficial lesions of the udder and teats as well as its potential for mastitis prevention. All drugs used yielded a 100% cure rate, but lysosubtilin application made it possible to achieve a statistically significant decrease (P < 0.05) in the duration of the recovery period (2.5 d versus 4.5 to 5.5 d) when compared with any of the four other drugs tested. Its efficacy for mastitis prevention was at least 3.4 times higher than the efficacy of the other medications used (statistically significant, P < 0.05, with regards to two of the four drugs) as well. We therefore conclude that lytic enzyme preparations are prospective antimicrobial drugs and when used to combat animal diseases they may serve as a possible alternative to common antibiotics.  相似文献   

16.
The aim of this work was to determine the effect of selenium (Se) deficiency on the porcine liver oxidative stability and to investigate Se content and oxidative status in porcine liver after dietary supplementation with vitamin E (vit E), sodium selenite, and selenized yeast. Experimental animals were fed a basal corn meal, low in Se and vit E, for a 4-week depletion period before being given the experimental diets containing different levels of Se and/or vit E for 5 months. Dietary treatments were the basal diet with no additions (control); the basal diet supplemented with 25 mg of vit E/kg of feed (group I); basal diet + 0.3 mg selenite-Se/kg (group II); basal diet + 0.3 mg selenized yeast-Se/kg (group III); basal diet + 0.1 mg selenite-Se + 10 mg vit E/kg (group IV); and basal diet + 0.3 mg selenite-Se + 25 mg vit E/kg (group V). The Se content in pig liver samples was 33 to 192% lower in the control group than in all the other groups. Dietary Se from selenized yeast had a more pronounced effect on Se level than dietary sodium selenite. The highest Se content was found in liver samples from the Se + vit E supplemented group (group V). All the dietary supplementation schemes significantly improved the oxidative status of porcine liver compared with the control group samples. The best results were obtained by simultaneous dietary supplementation with Se + vit E (groups IV and V) > group III > group II > group I.  相似文献   

17.
The present study was designed to investigate and compare the effects of dietary selenium (Se) and vitamin E on some physiological parameters and histological changes in liver, heart, and skin tissues, as well as the blood parameters and the related enzymes. Both sex young rabbits were fed with deficient (9.8 micrograms/kg diet), adequate (225 micrograms/kg diet), and rich (4.2 mg/kg diet) Se and vitamin E diets for 12-15 wk for this purpose. As the plasma Se levels and the erythrocyte glutathione (GSH) peroxidase activity decreased (79.8 +/- 9.4 ng/mL and 2.0 +/- 0.3 U/g Hb, respectively) in the deficient group, these values increased (100.4 +/- 2.7 ng/mL and 14.5 +/- 4.3 U/g Hb) in the rich group significantly with respect to the control group. The other antioxidant enzyme activities and the related element levels did not change significantly in either one of the experimental groups. Although the platelet counts of the two experimental groups were not different from the control values, the collagen and the adenosine diphosphate (ADP) stimulated platelet aggregation rate and intensity increased in the deficient group (p < 0.05) and decreased very significantly (p < 0.001) in the rich group. In both of the experimental groups, as the percentage values of the neutrophils decreased, the lymphocytes and the eosinophils increased significantly. According to the light microscopic investigations, the observed lesions of considerable intensity within the tissues that elicit cell degenerations were more pronounced in the animals fed with the rich diet than in those fed with the deficient diet. The deficiency as well as toxicity of Se and the deficiency of vitamin E caused several alterations in the physiological functions of the tissues, and these alterations were supported by the histological lesions within these tissues.  相似文献   

18.
In 17 patients with osteitis and 16 polytraumatized patients changes in the plasma levels of vitamin A, vitamin E and beta-carotene were investigated. Plasma samples taken preoperatively, daily during the first three days and then twice a week postoperatively were analysed for fat-soluble vitamins by high performance liquid chromatography (HPLC). Significant changes in plasma levels of all three components depending on the outcome of injury were found in all patients. Increased levels were observed in patients that survived the injury, while in those who died a significant decrease was observed. Recommendations regarding the supplementation with these vitamins in clinical practice can not be made based on these results, but substitute might prove beneficial for vitamin E in certain types of injury.  相似文献   

19.
The DNA adduct 8-hydroxy-2'-deoxyguanosine (8-OHdG) has been widely used as a biomarker for oxidative stress. Bulky DNA adducts, which are detectable by the 32P-postlabelling method, provide evidence for exposure to and metabolic activation of large, mainly apolar compounds, e.g. polycyclic aromatic hydrocarbons. We determined both types of adducts in placental tissues of 30 term pregnancies and related the adduct levels to the exposure to tobacco smoke and the plasma antioxidant status. Urine and plasma continine concentrations were used to select 10 nonsmokers, 9 nonsmokers exposed to environmental tobacco smoke (ETS) and 11 smoking women. Placental levels of 8-OHdG were 0.84 +/- 0.11, 0.90 +/- 0.21 and 0.83 +/- 0.20/10(5) deoxyguanosine bases (dG) for nonsmokers, nonsmokers exposed to ETS and smokers, respectively. The differences between the groups were not significant. Smoking women had significantly lower plasma vitamin C and beta-carotene concentrations than nonsmoking women or nonsmoking women exposed to environmental tobacco smoke. The 8-OHdG adduct level in placental DNA was inversely correlated with the plasma vitamin E concentration (r = -0.47, P < 0.05). There was no association between placental 8-OHdG adducts and vitamin A, C and beta-carotene in plasma. In total, 15 different adducts could be identified in the 30 placenta samples by the 32P-postlabelling method. There was a strong inter-individual variation in both the number of adducts and adduct intensities. No smoking-related or vitamin-related effects on adduct patterns or intensities were found. Our findings suggests that, within the limits of the methods used, tobacco smoke exposure during pregnancy does not lead to a measurable increase in placental DNA adduct levels and that vitamin E appears to have a protective effect on placental 8-OHdG formation.  相似文献   

20.
This study was undertaken to evaluate relationships between blood or serum levels of lead (Pb), calcium, and 25-hydroxyvitamin D (25-OHD), within the framework of a nutritional survey of lead-burdened children. The results demonstrate that: regardless of blood Pb concentration and season of the year, serum 25-OHD concentration reflects vitamin D intake; high blood Pb (greater than or equal to 60 microgram/dl) was associated with decreased levels of 25-OHD (18+/--1 ng/ml vs. 32+/- in controls, P less than .001); concentrations Pb and calcium were inversely correlated in control and lead-burdened children; and children in the high blood Pb group (greater than or equal to 60 microgram/dl) had lower mean daily intakes of both calcium (610 +/- 20 mg vs. 770 +/- 20 in controls, P less than .001) and vitamin D (210 +/- 17 IU vs. 325 +/- 20 in controls, P less than .001). These data indicate that, in Pb-burdened children, multiple factors modify the absorption and toxicity of Pb, and relative vitamin D deficiency, not excess, is associated with high blood Pb levels. Assessment of nutrition, calcium metabolism, and vitamin D status is recommended in evaluating children known to have undue absorption of Pb.  相似文献   

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