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1.
To determine the content of total iron (TFe) and heme iron (HeFe) in major cuts of meat and principal viscera of bovine origin. 55Fe (30 mCi) was injected into two 4-month-old calves. Triplicate samples of the 12 basic American cuts of meat and major viscera were obtained from each specimen. Samples were acid digested and their iron content was read by atomic absorption spectrophotometry. Duplicate samples of the basic cuts of meat and major viscera were analyzed to determine the concentration of 55Fe using a double isotopic technique. The mean and standard deviation of TFe for all cuts was 1.4?±?0.3 mg/100 g of meat. The mean TFe for organs was (per mg/100 g): 0.9?±?0.1 brain, 3.0?±?0.05 kidney, 3.2?±?0.04 heart, 5.7?±?0.2 lung, 6.0?±?0.1 liver, and 31.2?±?0.4 spleen. HeFe was 64% of TFe in meat and 72.8% in spleen, 53.8% in lung, 35.7% in brain, 35.0% in kidney, 27.3% in heart, and only 13.6% in liver. Blood contained 85.5% of the radioisotope and only 1.4% was found in muscle and 1.6% was found in viscera. Results suggest that bovine cuts of meat have a low variation in TFe and that HeFe comprises more than 60% of TFe.  相似文献   

2.
Although there are many studies on effect of fluoride on trace elements in experimental animals, few studies exist on serum trace elements levels in patients with endemic fluorosis. We aimed to determine the serum levels of trace elements including serum copper (Cu), zinc (Zn), and serum levels of minerals including calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na), potassium (K) in patients with endemic fluorosis. The study group consisted of 30 patients with endemic fluorosis (17 females, 13 males, mean age 33.53 ± 9.85 years). An age, gender, and body mass index matched 30 healthy volunteers comprised control group (21 females, ten males with a mean age 33.93 ± 7.39 years). Urine fluoride levels of chronic fluorosis patients were significantly higher than that of control subjects as expected (1.92 ± 0.10 mg/l vs. 0.41 ± 0.09 mg/l, respectively; P < 0.001). Serum Cu levels (89.14 ± 16.77 μg/dL vs. 102.69 ± 25.04 μg/dL, respectively, P = 0.017), serum Zn levels (77.98 ± 20.58 μg/dL vs. 94.57 ± 35.87μg/dL, respectively, P = 0.032), and serum Mg levels (1.92 ± 0.18 mg/dL vs. 2.07 ± 0.31 mg/dL, respectively, p = 0.022) was significantly lower in chronic fluorosis patients than in controls. There were no statistically significant differences between the fluorosis group and control group with respect to serum levels of Na, K, Ca, and P. We concluded that chronic fluorosis is associated with reduced serum levels of Cu, Zn, and Mg.  相似文献   

3.
Laparoscopic adjustable gastric banding (LAGB) causes significant weight loss in morbidly obese adults. However, its consequences on nutritional status still remain unclear. There are a few studies determining the nutritional status after LAGB and none have focused on the serum levels of zinc (Zn), copper (Cu), and ceruloplasmin (CP). We aimed to investigate the effects of LAGB surgery on plasma Zn, Cu, and CP levels. Thirty patients with LAGB with morbid obesity were included. Blood samples were collected preooperatively and in the postoperative third month to determine plasma Zn, Cu, and CP levels. The mean preoperative and postoperative body mass indexes (BMI) were 44.9 ± 7.4 kg/m2 and 44.1 ± 6.5 kg/m2, respectively. The mean weight loss was 12.9 ± 3.3 kg at the postoperative third month. The postoperative Zn (500 ± 130 ng/ml), Cu (280 ± 80 ng/ml), and CP (23.9 ± 8.8 mg/dl) values were statistically significantly lower than the preooperative Zn (740 ± 230 ng/ml), Cu (370 ± 80 ng/ml) and CP (33.3 ± 15.7 mg/dl) levels (p < 0.05). Decreases in the plasma levels of Zn, Cu, and CP were seen postoperatively following LAGB surgery. The nutritional status of LAGB-applied patients should be monitored and mineral supplementation may be considered.  相似文献   

4.
Sera of 890 healthy Jinan residents were chosen randomly, and the concentrations of serum Zn and Cu were detected by atomic absorption spectrometry. The mean serum Zn and Cu concentrations and Zn/Cu were 1.32 ± 0.49 mg/l, 0.99 ± 0.26 mg/l, and 1.41 ± 0.56, respectively. Significantly higher levels of serum Zn and Zn/Cu but lower serum Cu were found in the men. Descending tendency of serum Zn and Zn/Cu was observed with social-economic status and age but not significant. Alcohol consumption produced higher level of serum Zn and Zn/Cu but lower Cu concentration. Smoking caused significant lower level in serum Cu concentration but no significance in serum Zn and Zn/Cu. Serum Zn and Zn/Cu were normal only when hours of sleep a night were kept within 7–9 h. Higher level of serum Zn and Cu concentrations and Zn/Cu were observed in individuals with regular physical exercise, but still no significant difference existed. No clear relationship between educational levels with serum Zn and Cu concentrations and Zn/Cu was observed.  相似文献   

5.
The levels of zinc, copper, iron, and manganese were measured in the hippocampus, thalamus, gyrus cinguli, hypothalamus, and in the prefrontal, parietal, temporal, and occipital cortexes of lamb brain by flame atomic absorption spectrometry. Standard addition method was also applied to samples and it was observed that there was no matrix interference affecting the determination of elements interested. In the determination of Cu, a slotted tube atom trap was used to improve sensitivity. One-way analysis of variance was used for the statistical evaluation of the results for each element. Limit of detection results for Zn, Cu, Fe, and Mn were found to be 24, 4.5, 60, and 25 ng/mL, respectively. Region-specific differences were found for all elements interested. Mn concentration ranging from 0.29 ± 0.04 to 0.61 ± 0.04 mg/kg was found to be the lowest in all brain regions among the all elements interested.  相似文献   

6.
Deficiencies in Cu, Se, and Zn impair one or more biochemical functions, and excess are associated with toxicity. Baseline studies on the Ghanaian population are scanty. The study was undertaken to determine whether significant rural/urban differences in the serum levels of Cu, Se, and Zn did exist. Forty males/60 females from rural and 50 males/50 females from urban Ghanaian communities were sampled. Serum Cu, Se, and Zn were determined using flame atomic absorption spectrometry. Cu level for rural and urban subjects was 997 ± 333 and 979 ± 290 μg/L, respectively (p = 0.68). However, Cu levels were significantly higher in the rural females (1,063 ± 367 μg/L) than the rural males (898 ± 249 μg/L; p = 0.0085). Se levels for rural/urban subjects were 97 ± 36 and 87 ± 31 μg/L, respectively (p = 0.03). Zn levels in the rural/urban subjects were 312 ± 218 and 150 ± 102 μg/L, respectively (p = 0.002). Additionally, Zn was significantly higher in rural females (428 ± 204 μg/L) than the urban females (166 ± 103 μg/L; p = 0.0002). Finally, Zn was significantly higher in rural females (428 ± 204 μg/L) than males (172 ± 116 μg/L; p = 0.0028). In conclusion, Cu, Se, and Zn were higher in the rural group compared to the urban group, and the generally low Zn levels were confirmed in another cohort follow-up study.  相似文献   

7.
Quantitative analysis of follicular fluid and granulosa cells from small, medium and large antral atretic follicles of goat (Capra hircus) ovaries was conducted to study the alterations in trace elements viz zinc (Zn), copper (Cu), manganese (Mn), and iron (Fe). The zinc content was lower in the follicular fluid (0.993 ± 0.001, 0.935 ± 0.002, 1.321 ± 0.001 μg/ml) and granulosa cells (0.867 ± 0.002, 0.801 ± 0.001, 1.073 ± 0.002 μg/mg) of small, medium, and large antral atretic follicles respectively than their respective controls. Copper quantity was higher in the follicular fluid (0.113 ± 0.001, 0.163±0.001 0.{163}\pm 0.00{1} , 0.224 ± 0.001 μg/ml) and granulosa cells (0.094 ± 0.001, 0.114 ± 0.001, 0.182 ± 0.001 μg/mg) from small, medium, and large antral atretic follicles respectively than their respective controls. Similarly, iron and manganese was also found higher in the follicular fluid and granulosa cells of small, medium, and large antral atretic follicles than their respective controls. The present study provides the basic data on trace elements that can be safely used as atretic marker and will find use in in vitro studies for fertility improvement plan. Thus, help in elevating the number of ovulations and screening of follicles to enhance the success rate in vivo and in vitro fertilization and embryo transfer technology.  相似文献   

8.
Changes in the cupper (Cu) and zinc (Zn) concentrations have been reported previously in idiopathic dilated cardiomyopathy (IDCMP). As a result of controversial results, the aim of this study was to compare the Zn and Cu concentrations and Zn/Cu ratio of IDCMP patients to healthy volunteers. In addition, the correlation of Cu and Zn levels with age has been evaluated. The study population consisted of 18 IDCMP patients and 27 healthy volunteers. IDCMP patients had normal angiography with echocardiography supporting cardiomyopathy without pericardial and valvular diseases. Exclusion criteria were renal or hepatic insufficiency, alcohol usage, and intake of supplements containing Cu or Zn within 1 week ago. Cu and Zn levels have been assayed with atomic absorption spectrophotometry. Statistical analysis was performed with SPSS 10 software with independent sample t test for comparing the level of Cu and Zn of IDCMP patients with normal subjects and Pearson correlation to determine the correlation between numeric data. P < 0.05 was considered as significant differences. There was a trend for a lower Zn level in IDCMP patients compared to healthy volunteers. (0.97 ± 0.25 mg/l vs. 1.12 ± 0.42 mg/l, respectively). The mean Cu levels of IDCMP and normal subjects were 1.33 ± 0.20 mg/l and 1.31 ± 0.23 mg/l, respectively. There was a significant difference in Zn/Cu ratio among patients based on the NYHA classification of heart failure (P = 0.003). Age was negatively correlated with Zn levels in IDCMP group (P = 0.037) and positively with Cu levels in healthy volunteers (P = 0.012). A lower Zn level in IDCMP patients compared to healthy volunteers and specially a significant difference in Zn/Cu ratio of patients based on their NYHA classification would suggest a critical role of zinc and Cu imbalance in development of IDCMP.  相似文献   

9.
Premature graying of hair with unclear etiology, which is known as premature canities, is a common cause of referrals to the dermatologists. We assessed the relationship between serum iron, copper, and zinc concentrations with premature canities. This study was conducted on patients under 20 years old suffering from premature canities, having a minimum of ten gray hair fibers, and referring to university hospitals of Isfahan (Iran). The results were compared with age–sex-matched controls. Demographic data and disease characteristics were recorded for two groups. We studied serum iron, copper, and zinc concentrations of 66 patients and 66 controls using atomic absorption and Ferrozine methods. The mean age of studied cases was 17.8 ± 2.0 years, and the mean age of the onset of canities was 15.5 ± 3.2 years with no significant difference between males and females (P > 0.05). Serum copper concentration was significantly lower in patients compared with controls (90.7 ± 37.4 vs. 105.3 ± 50.2 μg/dL, P = 0.048), but serum iron concentration was significantly lower in controls compared to patients (88.8 ± 39.5 vs. 108.3 ± 48.4 μg/dL, P = 0.008). Also, there was no significant difference between patients and controls in serum zinc concentration (114.8 ± 67.8 vs. 108.2 ± 49.9 μg/dL, P = 0.285). According to these results, among copper, zinc, and iron, a low serum copper concentration may play a role in premature graying of hairs in our society. Further studies are needed to find the underlying mechanism of this relationship.  相似文献   

10.
We have determined the trace element composition of anti-influenza virus mushrooms using atomic absorption spectrophotometer. The elements present in greater concentration in Ganoderma lucidum samples are selenium, iron, and zinc, with selenium being the element with the highest concentration of all, at 416 ± 38.5 mg/kg; in Cordyceps militaris samples are iron, selenium, and zinc, with iron being the element with the highest concentration of all, at 291 ± 20.9 mg/kg; in Kuehneromyces mutabilis samples are selenium, iron, and manganese, with selenium being the element with the highest concentration of all, at 203 ± 9.8 mg/kg; in Inonotus hispidus samples are zinc, selenium, and iron, with zinc being the element with the highest concentration of all, at 194 ± 16.9mg/kg; in the Collybia maculata samples are iron, selenium, and zinc, with iron being the element with the highest concentration of all, at 274 ± 22.2 mg/kg, respectively. The average metal concentrations in mushrooms decreases in the order: selenium > iron > zinc > chromium > manganese > copper > magnesium > lead. After the mice were administered (orally) with mushroom extracts for 8 weeks and inoculated intranasally with viral suspension, element levels in serum were also measured. Highly significantly increased values of Se, Zn, and Mg in the serum of mice supplemented with anti-influenza virus mushrooms were a characteristic finding. Se, Zn, and Mg present in mushrooms may play a direct or indirect role in their anti-influenza virus nature. They may provide prophylactic protection against influenza infection via stimulation of host innate immune response.  相似文献   

11.
Research works that would determine the content of chemical elements in black population organisms on the basis of hair analysis are not numerous. There are no studies referring to black populations living in indigenous environment, like the Mafinga region, Iringa District in Tanzania examined by us. The aim of the study performed was to analyse the content of chemical elements Fe, Ca, Mg, Zn and Cu in easily available biological media like hair. The material was collected in October 2005 and March 2006 during anthropological examination, which came from young males (n = 91), students of a secondary school. Large Ca concentration range was found for the total number of subjects (680.20 to 2,089.70 μg/g d.m.). Mean Fe content in hair for the total number of subjects was 11.19 ± 3.70 μg/g d.m., while that of Mg 6.84 ± 2.02 μg/g d.m. Mean Zn concentration for the total number of subjects was 91.06 ± 39.22 μg/g d.m., being significantly higher in younger group than in older one (p = 0.039). Mean Cu concentration in hair for the total number of subjects was 7.50 ± 2.90 μg/g d.m Body mass index (BMI = kg/m2) was calculated for the subjects showing that out of 91 men participating in the study 15.4% was characterised by mediocre nutrition. No statistically significant correlations were found between BMI and the analysed chemical elements. The analysis of the content of trace elements in the hair of the examined young males showed deficiencies in Zn, Cu, Fe and significantly in Mg.  相似文献   

12.
Concentration level of nine elements viz. Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li were determined in leaves and roots of Asparagus curillus (Buch.-Ham.) ex Roxb. collected from four different altitudes in three seasons by atomic absorption spectroscopy. The overall concentration of K was found to be highest, whereas the level of Cu was lowest. The maximum concentrations of Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li were found to be 97.0 ± 1.5, 28.0 ± 7.0, 44.0 ± 7.3, 1138.0 ± 18.5, 91.0 ± 6.2, 381.0 ± 7.8, 9508.0 ± 7.8, 3076.0 ± 6.4, and 78.0 ± 4.6 mg/kg, respectively.  相似文献   

13.
One hundred twenty crossbred piglets (Duroc × Landrace × Yorkshire) were used to determine the effects of dietary zinc glycine chelate on growth performance, tissue mineral concentrations, and serum enzyme activity. All pigs were allotted to four treatments and fed with basal diets supplemented with 0, 50, and 100 mg/kg Zn as zinc glycine chelate or 3,000 mg/kg Zn as zinc oxide (ZnO). After the 35-day feeding trial, results of the study showed that, compared to the control, average daily gain was improved (P < 0.05) for pigs fed 100 mg/kg Zn from zinc glycine chelate or 3,000 mg/kg Zn from ZnO and Zn concentrations in serum and M. longissimus dorsi were significantly enhanced by 100 mg/kg dietary zinc glycine chelate and 3,000 mg/kg ZnO. In addition, supplementation of 100 mg/kg zinc glycine chelate decreased (P < 0.05) the liver Fe level, liver Zn level, spleen Cu level, and kidney Cu level compared to that of the 3,000-mg/kg ZnO group. For feces mineral excretion, 3,000 mg/kg Zn from ZnO greatly increased the concentration of fecal Zn (P < 0.01) and Mn (P < 0.05) compared to that of the control or the 100-mg/kg zinc glycine chelate group. Moreover, alkaline phosphatase and Cu/Zn superoxide dismutase activities of pigs in 100 mg/kg zinc glycine chelate and ZnO treatments were greatly higher than that of the control. The results of present study showed that supplementation with zinc glycine chelate could improve growth and serum enzyme activities and could also decrease zinc excretion in feces in weanling pig compared to high dietary ZnO.  相似文献   

14.
Changes in the copper (Cu) and zinc (Zn) concentrations have been reported previously in ischemic cardiomyopathy (ISCMP). Due to controversial results, the aims of this study were to compare levels of Cu, Zn, and Zn/Cu ratio of ISCMP patients with healthy volunteers and also to investigate the possible relationship between trace elements status in ISCMP patients with the severity of clinical disease based on the New York Heart Association (NYHA) classification. The subjects of this study consisted of 30 ISCMP and 27 healthy volunteers. ISCMP was diagnosed with a history of previous myocardial infarction and also coronary artery disease was confirmed by coronary angiography. Exclusion criteria were renal or hepatic insufficiency, alcohol usage, and intake of supplements containing Cu or Zn within 1 week. Cu and Zn levels have been assayed with atomic absorption spectrophotometry. Statistical analysis was performed with the SPSS 10 software using independent sample t test for comparing the levels of Cu and Zn between ISCMP and normal subjects. The mean Cu level of the ISCMP group (1.54 ± 0.52 mg/L) was significantly more than the Cu levels of the healthy volunteers (1.31 ± 0.24 mg/L; p = 0.048). The mean Zn levels of the ISCMP and healthy volunteers were 1.05 ± 0.28 and 1.12 ± 0.42, respectively, without any significant difference between groups. There was a trend for higher Cu level, lower Zn level, and lower Zn/Cu ratio in NYHA III patients in comparison with NYHA II group. Considering the results of this study, Cu may have a role in the development of ISCMP. Interventions such as administration of Cu chelators to relieve the symptoms or to decrease the progression of ISCMP is needed to be examined in large clinical trials. In this study, the Zn level of ISCMP patients was not significantly different in comparison with the healthy volunteers.  相似文献   

15.
The purpose of the study was to determine the concentration of trace elements present in scalp hair sample of schizophrenic patients and to find out the relationship between trace elements level and nutritional status or socioeconomic factors. The study was conducted among 30 schizophrenic male patients and 30 healthy male volunteers. Patients were recruited from Bangabandhu Sheikh Mujib Medical University by random sampling. Hair trace element concentrations were determined by flame atomic absorption spectroscopy and analyzed by independent t test, Pearson’s correlation analysis, regression analysis, and analysis of variance (ANOVA). Mn, Zn, Ca, Cu, and Cd concentrations of schizophrenic patients were 3.8 ± 2.31 μg/gm, 171.6 ± 59.04 μg/gm, 396.23 ± 157.83 μg/gm, 15.40 ± 5.68 μg/gm, and 1.14 ± 0.89 μg/gm of hair sample, while those of control subjects were 4.4 ± 2.32 μg/gm, 199.16 ± 27.85 μg/gm, 620.9 ± 181.55 μg/gm, 12.23 ± 4.56 μg/gm, and 0.47 ± 0.32 μg/gm of hair sample, respectively. The hair concentration of Zn and Ca decreased significantly (p = 0.024; p = 0.000, respectively) and the concentration of Cu and Cd increased significantly (p = 0.021; p = 0.000, respectively) in schizophrenic patients while the concentration of Mn (p = 0.321) remain unchanged. Socioeconomic data reveals that most of the patients were poor, middle-aged and divorced. Mean body mass indices (BMIs) of the control group (22.26 ± 1.91 kg/m2) and the patient group (20.42 ± 3.16 kg/m2) were within the normal range (18.5−25.0 kg/m2). Pearson’s correlation analysis suggested that only Ca concentration of patients had a significant positive correlation with the BMI (r = 0.597; p = 0.000) which was further justified from the regression analysis (R 2 = 44%; t = 3.59; p = 0.002) and one-way ANOVA test (F = 3.62; p = 0.015). A significant decrease in the hair concentration of Zn and Ca as well as a significant increase in the hair concentration of Cu and Cd in schizophrenic patients than that of its control group was observed which may provide prognostic tool for the diagnosis and treatment of this disease. However, further work with larger population is suggested to examine the exact correlation between trace element level and the degree of disorder.  相似文献   

16.
Both total and dialyzable iron levels and corresponding dialyzability were determined in 108 duplicate meals during 36 consecutive days. Total mean iron fraction of 5.90 ± 4.97 mg was found in the meals. The iron supplied by the meals is directly and significantly (p < 0.05) correlated with macromicronutrient content (carbohydrates, fiber, and protein). The mean iron dialyzability (4.81 ± 3.25%) was low and not significantly different among the three primary meals (breakfast, lunch, and dinner). Significant interactions of several minerals on iron levels were found (p < 0.05). Iron dialyzability was only statistically influenced by zinc dialyzability in meals (p < 0.05). The dialyzed iron fraction present in meals was significantly correlated with protein and ascorbic acid levels (p < 0.01). The mean iron daily dietary intake was 17.7 ± 6.91 mg. The hospital meals provided enough iron. Foods of animal origin are primary sources of iron in diet.  相似文献   

17.
The purpose of the study was to determine the serum concentration of trace elements of panic disorder patients and to find out the relationship between trace element levels and nutritional status or socio-economic factors. The study was conducted among 54 panic disorder patients and 52 healthy volunteers. Patients were recruited from Bangabandhu Sheikh Mujib Medical University by random sampling. Serum trace element concentrations were determined by flame atomic absorption spectroscopy (for Mg, Zn, Ca, and Cu) as well as graphite furnace (for Mn). Data were analyzed by independent t test, Pearson’s correlation analysis, regression analysis, and ANOVA. The serum concentration of Mn, Zn, Ca, Cu, and Mg in panic disorder patients were 0.37 ± 0.30, 0.67 ± 0.20, 99.91 ± 15.15, 0.83 ± 0.23, and 21.14 ± 3.72 mg/L, while those were 0.4163 ± 0.2527, 0.86 ± 0.3, 106.6073 ± 18.6531, 0.8514 ± 0.3646, and 21.37 ± 2.03 mg/L in control subjects, respectively. The serum concentration of Zn decreased significantly (p = 0.001) in patient group. But the differences of the concentration of Mn, Ca, Cu, and Mg between patient and control group were not significant (p = 0.522, p = 0.065, p = 0.800, and p = 0.712, respectively). Socio-economic data reveal that most of the patients were very poor and middle aged. Mean BMIs of the control group (23.74 ± 2.71 kg/m2) and the patient group (22.62 ± 3.74 kg/m2) were within the normal range (18.5–25.0 kg/m2). There was no significant relationship between serum zinc level and BMI of patients (r = 0.038; p = 0.809). So the decreased level of serum zinc in panic disorder patients was not because of other reasons, but rather it may provide a prognostic tool for the diagnosis and treatment of this disease.  相似文献   

18.
The coastal marine sediments near Santa Rosalía on the eastern coast of the Baja California Peninsula (Mexico) are heavily polluted by metals due to copper mining and smelting over the past century (up to 1984). The present study compares the accumulation of metals in the brown seaweed Padina durvillaei from the central segment of the coast of Santa Rosalía (polluted by Co, Cu, Mn and Zn) and from two segments north and south of the known “hot spot”. The seaweed samples were collected in May and August 2004 and June 2005 at 13 stations located along the Santa Rosalía mining region. Heavy metal concentrations were measured by instrumental neutron activation analysis (Co and Fe) directly in dried homogenized subsamples or by flame atomic absorption spectrophotometry (Cd, Cu, Mn, Ni, Pb and Zn) after complete strong acid digestion of sub-samples. The means and standard deviations of the concentrations in dry tissues of Padina durvillaei specimens for all the studied metals and stations lie in the following sequence: Cd (3.6 ± 1.6 mg kg−1) < Co (6.5 ± 6.1 mg kg−1) < Pb (7.8 ± 6.2) < Ni (9.96 ± 5.28 mg kg−1) < Cu (53 ± 38 mg kg−1) < Zn (63 ± 43 mg kg−1) < Mn (295 ± 269 mg kg−1) < Fe (2243 ± 2325 mg kg−1). This increase of the average concentrations was statistically significant. Principal Component Analysis showed that Factor 1 (36.46%) displays high positive loadings for Co, Cu, Mn and Zn, reflecting the influence of local anthropogenic pollution on the seaweed composition, while Factor 2 (26.91%) is important for Co, Fe and Ni and probably corresponds to the adsorption or accumulation of terrigenous elements of the regional origin, while Factor 3, with a high positive loading for Pb and a high negative loading for Cd, is probably controlled by local and regional anthropogenic input of Pb and episodic supply of Cd by local upwellings. The results of ANOVA for each element do not show any significant differences between the average concentrations for Cd, Fe, Ni and Pb in the seaweed of the three segments, or between the central and southern segments for Cu, Mn and Zn. Cobalt contents in the seaweed from the northern and central segments are, however, significantly different from the southern segment. This indicates that element concentrations in Padina durvillaei generally do not follow the drastic increases and gradients of Cu, Co, Mn and Zn contents detected in surface sediments. The apparent contradiction could be explained by a low geochemical mobility of these metals in the polluted sediments, composed mainly of stable residues of smelter wastes, with very low content of organic matter usually driving diagenetic mobilization of some metals into interstitial waters and then to the overlying water.  相似文献   

19.
Three hundred and sixty healthy Ross × Ross 1-day-old broilers were used to study the effects of zinc glycine chelate (Zn-Gly) on oxidative stress, contents of trace elements, and intestinal morphology. All broilers were randomly assigned to six treatment groups, which replicates three times. Diets were as follows: (1) control (containing 29.3 mg zinc (Zn)/kg basic diet (0–21 days) and 27.8 mg Zn/kg (22–42 days)); (2) basic diet plus 30 mg Zn/kg from Zn-Gly; (3) basic diet plus 60 mg Zn/kg from Zn-Gly; (4) basic diet plus 90 mg Zn/kg from Zn-Gly; (5) basic diet plus 120 mg Zn/kg from Zn-Gly; and (6) positive control, basic diet plus 120 mg Zn/kg from zinc sulfate (ZnSO4). The results showed that the addition of 90 or 120 mg/kg Zn-Gly led to an improvement of activity of Cu/Zn superoxide dismutase and glutathione peroxidase and a reduction of malondialdehyde content in livers at 21 and 42 days. With 90 mg/kg Zn-Gly, the content of sera zinc increased by 17.55% (P < 0.05) in 21-day broilers and 10.77% (P > 0.05) in 42-day broilers compared with that of the control. Adding 120 mg/kg Zn-Gly or ZnSO4 to broilers' diets greatly enhanced the content of zinc in feces at 21 days (P < 0.05) and at 42 days (P < 0.05). For 42-day chickens, increased villus height and decreased crypt depth of the jejunum could be observed in the second growth stage of broilers fed with 90 mg/kg Zn-Gly. Also, intestinal wall thickness decreased (P < 0.05). In addition, adding 90 mg/kg Zn-Gly to the diet markedly elevated villus length of duodenum and decreased crypt depth of ileum (P < 0.05) in 42-day broilers.  相似文献   

20.
To measure the effect of acute copper (Cu) administration, given as an aqueous solution, on the absorption of iron (Fe), 29 healthy adult women participated in two iron absorption studies. Subjects received 0.5 mg of Fe, as ferrous sulfate, alone or with Cu, as copper sulfate, at 0.5:1, 1:1, or 2:1 Cu/Fe molar ratios (study I) or at 4:1, 6:1, or 8:1 Cu/Fe molar ratios (study II) as an aqueous solution on days 1, 2, 14, and 15 of the study. Fe absorption was assessed by erythrocyte incorporation of iron radioisotopes 55Fe and 59Fe. Geometric mean (range ± SD) absorption of Fe alone or at 0.5:1, 1:1, 2:1 Cu/Fe molar ratios were 34.4% (17.3–68.5%), 40.9% (24.9–67.2%), 48.3% (24.8–94.1%), and 50.2% (25.3–99.5%), respectively (ANOVA, p = 0.12). Geometric mean (range ± SD) absorption of Fe alone or at 4:1, 6:1, 8:1 Cu/Fe molar ratios were 28.7% (12.1–67.9%), 21.5% (6.5–71.5%), 29.6% (10.3–85.4%), and 36.5% (18.3–73.1%), respectively (ANOVA, p = 0.16). In conclusion, combined Cu and Fe administration in an aqueous solution does not inhibit Fe bioavailability. This information could help in the design of rational guidelines for copper and iron supplementation programs. Our results support the hypothesis that divalent metal transporter 1 is not physiologically relevant for copper absorption in humans.  相似文献   

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