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1.
The aim of the present study is to evaluate the status of plasma essential trace element selenium (Se), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) concentrations and the effect of these elements on oxidative status in patients with childhood asthma. Plasma Se, Mn, Cu, and Zn concentrations were determined by atomic absorption spectrophotometry (AAS) and Fe concentrations, malondialdehyde (MDA), and total antioxidant capacity (TAC) were determined by the colorimetric method. The plasma MDA/TAC ratio was calculated as an index of oxidative status. Plasma albumin levels were measured to determine nutritional status. Plasma Fe concentrations, MDA levels and the MDA/TAC ratio were significantly higher (p<0.001, p<0.001, and p<0.01, respectively) and Se and Mn concentrations and TAC were lower (p<0.01, p<0.05, and p<0.01, respectively) in patients when compared to the healthy subjects. Plasma Zn, Cu, and albumin levels were not found to be significantly different in patients and controls (p>0.05). There were positive relationships between plasma MDA and Fe (r=0.545, p<0.001) and TAC and Se (r=0.485, p<0.021), and a negative correlation between TAC and MDA values (r= −0.337, p<0.031) in patients with childhood asthma. However, there was no correlation between these trace elements and albumin content in patient groups. These observations suggest that increased Fe and decreased Se concentrations in patients with childhood asthma may be responsible for the oxidant/antioxidant imbalance.  相似文献   

2.
The aim of the present study is to evaluate the status of plasma essential trace elements selenium (Se), zinc (Zn), copper (Cu), and iron (Fe) concentrations and their related acute-phase proteins, ceruloplasmin (Cp), ferritin, transferrin (Tf), and albumin levels in patients with vivax malaria. Plasma Cu and Zn concentrations were determined by atomic absorption spectrometry (AAS). Se concentrations were determined by graphite furnace AAS. Fe, Cp, Tf, and albumin levels were determined by colorimetric methods. Plasma Se, Fe, and albumin levels were found to be significantly lower (p<0.01, p<0.001, and p<0.05, respectively) and Cu, Cp, and ferritin levels and Cu/Zn ratios were significantly higher (p<0.001, p<0.001, p<0.001, and p<0.05, respectively) in patients when compared with those of healthy subjects. Plasma, Tf, and Zn levels were not found to be significantly different (p>0.05) in patients and controls. There were positive important correlations between Cu and Cp (r=0.908, p<0.001), Zn and albumin (r=0.633, p<0.001), and negative correlations between Fe and ferritin content (r=−0.521, p<0.05) and Fe and Tf (r=−0.616, p<0.01) in the patients group. Our findings demonstrated that plasma essential trace elements Se, Cu, and Fe change, but these changes might be dependent on acute-phase proteins, which were regulated as a part of defense strategies of the organism, induced by hormonelike substances.  相似文献   

3.
Iron overload could promote the generation of free radicals and result in deleterious cellular damages. A physiological increase of oxidative stress has been observed in pregnancy. A routine iron supplement, especially a combined iron and vitamin C supplementation, without biological justifications (low hemoglobin [Hb] and iron stores) could therefore aggravate this oxidative risk. We investigated the effect of a daily combined iron supplementation (100 mg/d as fumarate) and vitamin C (500 mg/d as ascorbate) for the third trimester of pregnancy on lipid peroxidation (plasma TBARS), antioxidant micronutriments (Zn, Se, retinol, vitaminE, (β-carotene) and antioxidant metalloenzymes (RBC Cu-Zn SOD and Se-GPX). The iron-supplemented group (n=27) was compared to a control group (n=27), age and number of pregnancies matched. At delivery, all the women exhibited normal Hb and ferritin values. In the supplemented group, plasma iron level was higher than in the control group (26.90±5.52 mmol/L) and TBARs plasma levels were significantly enhanced (p<0.05) (3.62±0.36 vs 3.01±0.37 mmol/L). No significant changes were observed in plasma trace elements and red blood cell antioxidant metalloenzymes. Furthermore, the α-tocopherol plasma level was lowered in the iron-supplemented groups, suggesting an increased utilization of vitamin E. These data show that pharmalogical doses of iron, associated with high vitamin C intakes, can result in uncontrolled lipid peroxidation. This is predictive of adverse effects for the mother and the fetus. This study illustrates the potential harmful effects of iron supplementation when prescribed only on the assumption of anemia and not on the bases of biological criteria.  相似文献   

4.
The concentrations of cadmium, lead, selenium, and zinc in blood and seminal plasma were determined in 76 Singapore males. Except for zinc, the concentrations were generally higher in blood than in seminal plasma (cadmium, 1.31 μg/L vs 0.61 μg/L; lead, 82.6 μg/L vs 12.4 μg/L, and selenium, 163.6 μg/L vs 71.5 μg/L). The mean concentration of zinc in seminal plasma was more than 30 times higher than in blood (202 mg/L vs 6.2 mg/L). Significant positive correlations were found between the concentrations in blood and seminal plasma for the two essential trace elements: selenium (r=0.45,p<0.001) and zinc (r=0.25,p<0.05). However, no relationships were found between the concentrations in blood and seminal plasma for two toxic metals (cadmium and lead). Significant inverse correlations were observed between Cd and Zn (r=−0.40,p<0.01), and Pb and Se (r=−0.32,p<0.05) in blood, whereas significant positive correlations were noted between Cd and Se (r=0.45,p<0.01), Cd and Zn (r=0.35,p<0.05), and Se and Zn (r=0.57,p<0.001) in seminal plasma. The physiological significance of these relationships are also discussed in this paper.  相似文献   

5.
The study describes the concentrations of zinc, magnesium, copper, iron, and biochemical markers of seminal vesicle and prostate in seminal plasma of different categories of infertile men. The zinc level in oligasthenospermic subjects was significantly higher than in azoospermic, asthenospermic, and oligospermic subjects. The γ-glutamyl transpeptidase activity in both oligoasthenospermic and azoospermic subjects were significantly lower than in asthenospermic and oligospermic individuals. There was no significant difference in iron, copper, and magnesium levels and acid phosphatase activity among the different infertile categories. A positive correlation between zinc and acid phosphatase (r=0.84, r=0.73; p<0.05), and between copper and fructose (r=0.81, r=0.72; p<0.05) was observed in oligoasthenospermic and azoospermic men, respectively. On the basis of our results, it may be postulated that there is a direct effect of the trace elements zinc and copper on acid phosphatase and fructose, respectively, in oligoasthenospermic and azoospermic subjects.  相似文献   

6.
In recent years, a great number of studies have investigated the possible role of trace elements in the etiology and pathogenesis of rheumatoid arthritis (RA) and osteoartritis (OA). We studied synovial fluid and plasma concentrations of selenium (Se), zinc (Zn), copper (Cu), and iron (Fe) in patients with RA and OA and compared them with sex- and age-matched healthy subjects. Plasma albumin levels were measured as an index of nutritional status. Plasma Se, Cu, and Zn concentrations were determined by atomic absorption spectrophotometry and Fe concentrations were determined by the colorimetric method. Although plasma and synovial fluid Se concentration were found to be significantly lower (p<0.05, and p<0.05, respectively), Cu concentrations were significantly higher in patients with RA than those of healthy subjects and OA (p<0.05 and p<0.05, respectively). There were no significant differences in plasma and synovial fluid Zn concentrations and albumin levels among three groups (p>0.05). On the other hand, synovial fluid Cu and Fe concentrations were significantly higher in patients with OA than those of healthy subjects (p<0.05). There was a significantly positive correlation between synovial fluid Se−Cu values and Zn−Fe values in patients with RA. Our results showed that synovial fluid and plasma trace element concentrations, excluding Zn, change in inflammatory RA, but not in OA. These alterations in trace element concentrations in inflammatory Ra might be a result on the changes of the immunoregulatory cytokines.  相似文献   

7.
In this study, we investigated the α-tocopherol plasma concentrations in healthy free-ranging nestlings of the white-tailed sea eagle (Haliaeetus albicilla) (n = 32), osprey (Pandion haliaetus) (n = 39), northern goshawk (Accipiter gentilis) (n = 25), common buzzard (Buteo buteo) (n = 31), and honey buzzard (Pernis apivorus) (n = 18) as well as of free-ranging adults of the white-tailed sea eagle (n = 10), osprey (n = 31), and northern goshawk (n = 45). α-Tocopherol plasma concentrations were determined by reverse-phase high-performance liquid chromatography. α-Tocopherol plasma concentrations in nestlings of osprey, white-tailed sea eagle, and northern goshawk did not differ significantly amongst the species, but the common buzzard and honey buzzard nestlings had significantly lower α-tocopherol plasma concentrations than nestlings of the other species (both P < 0.001). Adult male ospreys and white-tailed sea eagles had significantly higher α-tocopherol concentrations compared to adult females (both P < 0.005). Adult ospreys and northern goshawks had significantly higher α-tocopherol plasma concentrations compared to their nestlings (both P < 0.001). In adult female northern goshawks, plasma concentrations of α-tocopherol increased significantly before egg laying (P < 0.001). These results demonstrate α-tocopherol plasma concentrations in birds of prey to be species specific and influenced by age and reproductive status.  相似文献   

8.
This study aimed to compare the trace element status of patients with type 2 diabetes (n=53) with those of nondiabetic healthy controls (n=50). The concentrations of seven trace elements were determined in the whole blood, blood plasma, erythrocytes, and lymphocytes of the study subjects. Vanadium and iron levels in lymphocytes were significantly higher in diabetic patients as compared to controls (p<0.05 for iron and p<0.01 for vanadium). In contrast, lower manganese (p<0.01) and selenium (p<0.01) concentrations were detected in lymphocytes derived from patients with type 2 diabetes versus healthy subjects. Furthermore, significantly lower chromium levels (p<0.05) were found in the plasma of diabetic individuals as compared to controls. Trace element concentrations were not dependent on the degree of glucose control as determined by correlation analysis between HBA1c versus metal levels in the four blood fractions. In summary, this study primarily demonstrated that trace element levels in lymphocytes of patients with type 2 diabetes could deviate significantly from controls, whereas, in general, no considerable differences could be found when comparing the other fractions between both patient groups. Therefore, it seems reasonable to analyze metal levels in leukocytes to determine trace element status in patients with type 2 diabetes and perhaps in other diseases.  相似文献   

9.
This study evaluated levels of plasma zinc, copper, and leptin, body composition, and their relationship in nine elite female judo athletes under two different training conditions. Body composition and biochemical measurements (hematological indexes, plasma zinc, plasma copper, and plasma leptin) were analyzed 24 h after intense training and following a 5-d period without training (no-training). Plasma leptin and plasma zinc increased with no-training. Plasma zinc correlated negatively with percent fat mass (r=−0.62; r=0.05) and positively with plasma leptin (r=0.83; p=0.002) in the no-training condition Plasma copper did not change during the study and correlated positively with plasma leptin (r=0.66; p=0.05) and with percent fat mass (r=0.80; p=0.007) after training. Percent fat mass was associated negatively with plasma zinc (r=−0.62; p=0.05) in the no-training condition. Moreover percent fat mass was negatively associated with the Zn/Cu plasma ratio under both training conditions (r<−0.78, p<0.001). These results are consistent with the possible function of zinc as a lipid-mobilizing factor and of copper as a limiting factor in energy metabolism.  相似文献   

10.
This study was conducted to examine the relationship between the concentration of zinc and neutral α-glucosidase (NAG) with semen quality. Semen samples from 75 male partners of couples who were attending the Obstetrics and Gynecology Department were analyzed for semen quality. Based on sperm count, the subjects were divided into three groups. Zinc and neutral α-glucosidase activity were estimated in seminal plasma. Results showed that mean the α-glucosidase activity was lowest among the azoospermic group with respect to oligozoospermic and normozoospermic groups. Mean zinc levels were also lower among azoospermics compared to oligozoospermic and normospermic groups. The difference was statistically significant (p<0.05). A significant positive correlation was observed between zinc levels and sperm count (r=0.29, p<0.05) and zinc and α-glucosidase activity (r=0.31, p<0.05) in seminal plasma. These results suggest that zinc and neutral α-glucosidase seem to play an important role in human reproduction.  相似文献   

11.
Plasma and liver selenium of Wistar rats were determined after 1, 3, and 6 mo supplementation with 0.5, 2, 6, or 15 ppm selenium as sodium selenite in drinking water. Plasma selenium was not different from control values at additional intake of 0.5 ppm but increased above usual levels at higher intakes. A highly significant correlation was observed between the total quantity of selenium ingested and plasma selenium after 1 mo treatment (r=0.99,p<0.01), but was less pronounced after 3 and 6 mo (0.94,p<0.05, and 0.78,p<0.05, respectively). The decrease in plasma selenium with time of treatment was more pronounced at higher intakes. There was also a highly significant correlation between total selenium intake and liver selenium concentration (r=0.99,p<0.01) after 1 mo of treatment, but this time liver selenium did not change with time, and the correlation remained highly significant throughout the investigation. Liver selenium therefore appears as a more sensitive and more representative measure of selenium intake than plasma selenium. Most supplements did not affect body weight and survival of animals, except when the diet was supplemented with 15 ppm for 6 mo; however, alterations in biochemical parameters concerning lipid status and hepatic function were observed at levels above 2.0 ppm.  相似文献   

12.
Leptin, the obesity gene protein product, is a hormone with multiple physiological functions in the human. However, there are few reports in the literature on its role in trace element metabolism in the normal population. Therefore, we investigated the association among serum leptin, zinc, copper, and zinc/copper ratio in 570 healthy men and women aged 15 yr and older. Serum leptin assay was done with a commercial enzymelinked immunosorbent assay kit; serum zinc and copper levels were measured by an atomic absorption spectrophotometer. Serum leptin was found to be positively associated with age (r=0.254, p<0.001), sex (r=0.406, p<0.001), body mass index (BMI) (r=0.553, p<0.001), and serum copper (r=0.419, p<0.001), but negatively associated with the zinc/copper ratio (r=−0.423, p<0.001). There was no significant association between serum leptin and zinc (r=−0.131, p>0.05). When the confounding effects of age, sex, and BMI were removed, serum leptin was still positively associated with serum copper (r=0.197, p=0.02) and the serum zinc/copper ratio (r=−0.182, p=0.03). These results suggest that copper and not zinc has an effect on serum leptin levels.  相似文献   

13.
Objective: Leptin concentrations increase with obesity and tend to decrease with weight loss. However, there is large variation in the response of serum leptin levels to decreases in body weight. This study examines which endocrine and body composition factors are related to changes in leptin concentrations following weight loss in obese, postmenopausal women. Research Methods and Procedures: Body composition (DXA), visceral obesity (computed tomography), leptin, cortisol, insulin, and sex hormone‐binding globulin (SHBG) concentrations were measured in 54 obese (body mass index [BMI] = 32.0 ± 4.5 kg/m2; mean ± SD), women (60 ± 6 years) before and after a 6‐month hypocaloric diet (250 to 350 kcal/day deficit). Results: Body weight decreased by 5.8 ± 3.4 kg (7.1%) and leptin levels decreased by 6.6 ± 11.9 ng/mL (14.5%) after the 6‐month treatment. Insulin levels decreased 10% (p < 0.05), but mean SHBG and cortisol levels did not change significantly. Relative changes in leptin with weight loss correlated positively with relative changes in body weight (r = 0.50, p < 0.0001), fat mass (r = 0.38, p < 0.01), subcutaneous fat area (r = 0.52, p < 0.0001), and with baseline values of SHBG (r = 0.38, p < 0.01) and baseline intra‐abdominal fat area (r = ?0.27, p < 0.06). Stepwise multiple regression analysis showed that baseline SHBG levels (r2 = 0.24, p < 0.01), relative changes in body weight (cumulative r2 = 0.40, p < 0.05), and baseline intra‐abdominal fat area (cumulative r2 = 0.48, p < 0.05) were the only independent predictors of the relative change in leptin, accounting for 48% of the variance. Discussion: These results suggest that obese, postmenopausal women with a lower initial SHBG and more visceral obesity have a greater decrease in leptin with weight loss, independent of the amount of weight lost.  相似文献   

14.
15.
Selenium is an important trace element for brain function. Our objective was to analyse cerebrospinal fluid (CSF) selenium (Se) in 89 paediatric patients. We also studied correlations between Se and other biochemical variables (age, CSF protein concentrations and glutathione peroxidase activity and plasma Se values). Cerebrospinal fluid Se values showed a significant negative correlation with the age of patients (r = −0.476; p < 0.0001), and positive with CSF total protein concentrations and GPX activity (r = 0.446, p < 0.001; r = 0.431; p = 0.001, respectively). No association was observed between plasma and CSF Se concentrations. Median CSF Se values were 32 times lower when compared with those for plasma. In conclusion, CSF Se concentrations depend on age and total CSF protein values. The association observed between CSF Se and GPX activity suggests that Se quantification might be a reflection of some Se-dependent protein function. Cerebrospinal fluid Se values were independent of serum Se concentrations.  相似文献   

16.
Plasma retinol and α-tocopherol concentrations were measured in heparinized blood samples collected from 51 free-ranging adult Humboldt penguins (Sphenicus humboldti) residing at two colonies off the Chilean coast. Thirty samples were collected in April 1992 from penguins inhabiting the Ex-islote de los Pájaros Niños in Algarrobo, Chile. In September 1992, 21 samples were collected from birds inhabiting Isla de Cachagua, Chile. Samples were assayed for retinol, retinyl palmitate, α-tocopherol, γ-tocopherol, lutein, β-cryptoxanthin, lycopene, α-carotene, and β-carotene. Retinol, α-tocopherol, and lutein were detected in all samples, while lycopene and γ-tocopherol were not detected in any. A significantly higher percentage of samples had detectable levels of retinyl palmitate and α-carotene in April (P < 0.001): for β-cryptoxanthin the percentage was higher in September (P < 0.001). Plasma concentrations of α-tocopherol and lutein were higher in September. Alpha-tocopherol concentrations were 1,877.1 ± 99.0 (SEM) μg/dl in April compared to 2.289 ± 122.3 μg/dl in September (P < 0.05); lutein concentrations were 4.16 ± 0.43 μg/dl in April vs. 10.68 ± 1.02 μg/dl in September (P < 0.001). Retinol concentrations were not significantly different (117 ± 8.0 μg/dl in April vs. 105.3 ± 7.6 μg/dl in September). Both physiologic changes associated with season, and the change in locale may have contributed to the differences seen in the assay means and the number of samples with detectable levels. © 1996 Wiley-Liss, Inc.  相似文献   

17.
Background: Much experimental evidence suggests that lipid oxidation is important in atherogenesis and in epidemiological studies dietary antioxidants appear protective against cardiovascular events. However, most large clinical trials failed to demonstrate benefit of oral antioxidant vitamin supplementation in high-risk subjects. This paradox questions whether ingestion of antioxidant vitamins significantly affects lipid oxidation within established atherosclerotic lesions. Methods and results: This placebo-controlled, double blind study of 104 carotid endarterectomy patients determined the effects of short-term α-tocopherol supplementation (500 IU/day) on lipid oxidation in plasma and advanced atherosclerotic lesions. In the 53 patients who received α-tocopherol there was a significant increase in plasma α-tocopherol concentrations (from 32.66±13.11 at baseline to 38.31±13.87 (mean±SD) μmol/l, p&lt;0.01), a 40% increase (compared with placebo patients) in circulating LDL-associated α-tocopherol (p&lt;0.0001), and their LDL was less susceptible to ex vivo oxidation than that of the placebo group (lag phase 115.3±28.2 and 104.4±15.7 min respectively, p&lt;0.02). Although the mean cholesterol-standardised α-tocopherol concentration within lesions did not increase, α-tocopherol concentrations in lesions correlated significantly with those in plasma, suggesting that plasma α-tocopherol levels can influence lesion levels. There was a significant inverse correlation in lesions between cholesterol-standardised levels of α-tocopherol and 7β-hydroxycholesterol, a free radical oxidation product of cholesterol. Conclusions: These results suggest that within plasma and lesions α-tocopherol can act as an antioxidant. They may also explain why studies using &lt;500 IU α-tocopherol/day failed to demonstrate benefit of antioxidant therapy. Better understanding of the pharmacodynamics of oral antioxidants is required to guide future clinical trials.  相似文献   

18.
Objective: The metabolic syndrome is characterized by defective hepatic apolipoprotein B‐100 (apoB) metabolism. Hepato‐intestinal cholesterol metabolism may contribute to this abnormality. Research Methods and Procedures: We examined the association of cholesterol absorption and synthesis with the kinetics of apoB in 35 obese subjects with the metabolic syndrome. Plasma ratios of campesterol and lathosterol to cholesterol were used to estimate cholesterol absorption and synthesis, respectively. Very‐low‐density lipoprotein (VLDL), intermediate‐density lipoprotein (IDL), and low‐density lipoprotein apoB kinetics were studied using stable isotopy and mass spectrometry. Kinetic parameters were derived using multicompartmental modeling. Results: Compared with controls, the obese subjects had significantly lower plasma ratios of campesterol, but higher plasma ratios of lathosterol (p < 0.05 in both). This was associated with elevated VLDL‐apoB secretion rate (p < 0.05) and delayed fractional catabolism of IDL and low‐density lipoprotein‐apoB (p < 0.01). In the obese group, plasma ratios of campesterol correlated inversely with VLDL‐apoB secretion (r = ?0.359, p < 0.05), VLDL‐apoB (r = ?0.513, p < 0.01) and IDL‐apoB (r = ?0.511, p < 0.01) pool size, and plasma lathosterol ratio (r = ?0.366, p < 0.05). Subjects with low cholesterol absorption had significantly higher VLDL‐apoB secretion, VLDL‐apoB and IDL‐apoB pool size, and plasma lathosterol ratio (p < 0.05 in both) than those with high cholesterol absorption. Discussion: Subjects with the metabolic syndrome have oversecretion of VLDL‐apoB and decreased catabolism of apoB‐containing particles and low absorption and high synthesis rates of cholesterol. These changes in cholesterol homeostasis may contribute to the kinetic defects in apoB metabolism in the metabolic syndrome.  相似文献   

19.
The aim of this study was to determine whether the postprandial decline in plasma zinc concentration is altered by aging. Eleven women, between the ages of 65 and 82 yr, participated in two separate experimental protocols: a high carbohydrate breakfast trial and a fasting trial. Plasma zinc concentrations were measured from blood samples obtained at 8∶00am (baseline fasting) and at 30-min intervals until 1∶00pm during each trial. Following the breakfast meal, plasma zinc concentrations declined 14% from 75±1 to 65±2 μg/dL (p<0.05), reaching a nadir 2.7±0.2 h after the meal. This decline was significantly (p<0.0001) greater than the 3.6% fall observed during the fasting trial. Postprandial changes in the plasma zinc concentrations were correlated with postprandial changes in serum glucose (r=−0.43,p<0.001), serum insulin (r=−0.17,p<0.01), and serum phosphorus(r=0.32,p<0.005). These data show that plasma zinc concentrations decline following food intake in elderly women in the same manner as previously described for younger adult women.  相似文献   

20.
The effects of supplemental chromium (Cr) as chromic chloride hexahydrate in incremental dose levels (0, 0.5, 1.0, and 1.5 mg/day for 240 days) on metabolism of nutrients and trace elements were determined in dwarf Bengal goats (Capra hircus, castrated males, average age 3 months, n = 24, initial mean body weight 6.4 ± 0.22 kg). Live weight increased linearly (p < 0.05) with the level of supplemental Cr. Organic matter and crude protein digestibility, intake of total digestible nutrients, and retention of N (g/g N intake) increased (p < 0.05) in a dose-dependent linear manner. Serum cholesterol and tryacylglycerol concentrations changed inversely with the dose of supplemental Cr (p < 0.01). Supplemental Cr positively influenced retention of copper and iron (p < 0.05) causing linear increase (p < 0.01) in their serum concentrations. It was concluded that Cr supplementation may improve utilization of nutrients including the trace elements and may also elicit a hypolidemic effect in goats. However, further study with regards to optimization of dose is warranted.  相似文献   

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