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1.
Proton-induced X-ray emission (PIXE) analysis was employed to determine the concentrations of six elements in the plasma and erythrocytes of 18 cancer subjects (15 males and 3 females) with neoplastic disorders and in 70 controls (35 males and 35 females). It was found that the concentrations of Br, K, and Zn were significantly elevated in the erythrocytes of the cancer subjects compared to the controls, whereas the concentration of Fe was significantly depressed, but with no difference observed in the concentration of Ca. In the plasma, the concentrations of Br, Cu, Ca, and K were significantly elevated, whereas the concentrations of Fe and Zn were found to be significantly depressed compared to the controls.  相似文献   

2.
This study monitored total atmospheric deposit (TAD) around a smelting plant in Ile-Ife, Nigeria to assess the contributions of the industry to Nigeria's air-shed pollution. Samples were collected for 12 consecutive months using an Australian model gauge, harvested after 30 d of exposure, filtered and dried to constant weights using oven. Monthly deposition rates were determined and elemental characterizations of the TAD samples were done using proton-induced X-ray emission technique. Results revealed that the monthly deposition rates ranged from 0.69 to 4.62 gm?3 and was more pronounced in Harmattan. Twenty-three elements were detected; their total elemental concentrations ranged from 1.23 to 13.63 mg m?3 with Fe having the highest concentrations, while Na has the least. Pearson correlation indicated that some elements have common sources and/or similar chemical properties; enrichment factor showed that Fe, Zn, Pb, Mn were extremely enriched in the study area, modified degree of contamination (3.75) and pollution load intensity (1.21) showed that the neighborhoods could be exposed to high air pollution related impacts. Positive matrix factorization model revealed three distinct sources: Smelting emission (63%), biomass burning (17%), and suspended input material emissions (21%). The study concluded that the smelting activities posed a great hazard to receptors around the smelting industry.  相似文献   

3.
Variation in the distribution of trace elements in hepatoma   总被引:3,自引:0,他引:3  
There are many reports of reduction of zinc level and rise of copper level in serum of patients with liver disease. However, there are a few reports that compare the trace elements in tumor tissues and nontumor tissues of the liver with hepatoma. We studied trace element distribution in tumor tissues and nontumor tissues of liver with hepatoma and compared them with data from normal liver tissues. Zinc (Zn), copper (Cu), selenium (Se), cadmium (Cd), mercury (Hg), and iron (Fe) were chosen as the trace elements to be observed. We observed falls of Zn, Cd, and Hg levels in tumor tissues and the rise of Cu level as a result of this investigation. Zn, Cd, and Hg levels in tumor tissues were significantly lower than those in nontumor tissues and Zn, Cd, and Hg levels in nontumor tissues were significantly lower than in normal liver tissues. This tendency was clearer for Cd and Hg than for Zn. Although the distribution of Cu was not significant, a distribution contrary to that of Zn was shown. These findings indicate that the distribution of Zn, Cd, and Hg can serve as supportive evidence that could be useful as a tumor marker. Selenium showed almost the same accumulation tendency among tumor tissues, nontumor tissues, and normal livers. Although correlation was observed among most metals in the normal liver, there was almost no correlation in tumor tissues.  相似文献   

4.
A particle-induced X-ray emission (PIXE) analysis method is presented, which allows measurement of eight elements (i.e., K, Ca, Mn, Fe, Cu, Zn, Se, and Rb) in human brain samples of only a few mg dry weight. The precision and accuracy of the method were investigated by analyzing animal brain matter with both PIXE and instrumental neutron activation analysis (INAA). The method was applied to measure the 8 elements in 46 different regions of 3 human brains. The sections analyzed originated from either the left or the right cerebral hemisphere, brain stem, and cerebellum. For one of the brains, sections were also analyzed from 26 corresponding regions of both hemispheres. For all elements, similar concentrations were found in the corresponding areas of the left and right sides of the brain. The concentrations (in μg/g dry weight) of the elements K, Fe, Cu, Zn, Se, and Rb were consistently higher in cortical structures than in white matter. Deep nuclei and brain stem, which have a mixed composition, showed intermediate values for K, Zn, Se, and Rb. A hierarchical cluster analysis indicated that the various brain regions clustered into two large groups, one comprising gray and mixed matter regions and the other, white and mixed matter brain areas.  相似文献   

5.
Although altered levels of circulating essential trace elements are known to accompany malignant disease, the lack of sensitivity of conventional detection methods has generally limited their study to clinical conditions involving extensive disease (i.e., significant tumor burden). As such, the application of altered trace element levels as potential prognostic guides or as response indicators subsequent to treatment has been of limited use. During this study, proton-induced X-ray emission spectroscopy was evaluated as a tool to determine trace element imbalances in a murine tumor model. Using plasma from C57B1/6 mice bearing the syngeneic Lewis lung carcinoma (LLCa), levels of Fe, Cu, and Zn, as well as changes in the Cu/Zn ratio, were measured in animals carrying an increasing primary tumor burden. The plasma levels of Fe, Cu, and Zn were found to decrease significantly 7 d following implants of LLCa cells with no significant change observed in the Cu/Zn ratio. By d 21, however, an increase in the Cu/Zn ratio was found to accompany increased growth of the LLCa tumor; the plasma levels of Cu had returned to normal levels, whereas both the Fe and Zn plasma levels remained lowered. Collectively, the results suggest that although a net change in individual plasma trace element concentrations might not be accurately associated with tumor growth, a clear relationship was established between the Cu/Zn ratio and tumor size.  相似文献   

6.
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   

7.
Summary Two different immunocytochemical techniques based on specific antibodies against -subunits of porcine, rat and bovine TSH were applied at the ultrastructural level to identify the TSH cells in the porcine anterior pituitary and to compare the subcellular localization of the hormone.The post-embedding method on serial ultrathin sections revealed the localization of TSH in the granules of a specific cell type, negative for the other hormones. TSH was found in polyhedral cells characterized (i) by their content of granules that were the smallest of all the cell types examined, and (ii) by their flattened or slightly dilated RER cisternae. The pre-embedding method applied to isolated cells permitted a good penetration of antisera and the maintenance of antigenicity in sites inaccessible to the post-embedding method. Thus, immunoreactivity of TSH was detected in the secretory granules, the cytoplasmic matrix and in portions of the rough endoplasmic reticulum, in association with some membranes and inside some saccular structures.  相似文献   

8.
Summary Electron microscopic studies have been carried out on the innervation of the mammalian anterior pituitary and parathyroids. The total area of grid squares (2.25·10–2mm2) examined was 2000 per gland and species. In the pituitary pars distalis and in the parenchyma of the parathyroid gland we did not observe a single axon profile. According to the equation proposed by Hennig (1963) we have calculated that there might be—if any—0.133 mm of nerves per 1 mm3 tissue in those two endocrine glands (level of significance 0.95). Comparing these results to the degree of innervation in brown adipose tissue containing more than 160 mm nerve per 1 mm3 tissue we can not imagine that such a small degree of innervation is of any biological importance.In the pituitary pars tuberalis two types of axon terminals have been found both inside and outside the basement membrane surrounding the epithelial complexes. One type contains synaptic and two populations of smaller dense-cored vesicles, the other one contains a population of larger granules which have some properties of the classical elementary granules. Further investigations have to clarify the functional significance of those nerve endings.This investigation was supported by the Deutsche Forschungsgemeinschaft.  相似文献   

9.
Summary The ultrastructure of immunoreactive somatotrophs and lactotrophs in pituitaries of fetal rats at 19, 20 and 21 days of gestation and on the day of birth was studied. Somatotrophs, first detectable at 19 days of gestation, undergo only minor modifications before reaching the structure described for adults. In particular there is an increase in the endoplasmic reticulum and Golgi apparatus. Lactotrophs, first identifiable in newborn rats, are very different in ultrastructure from adult cells, because the secretory granules are generally small, but variable in shape and size, and the Golgi complex is prominent.  相似文献   

10.
Neuropeptide Y (NPY) has been recently localized in several hypothalamic nuclei in the mammalian brain. In order to investigate the possible role of NPY on neuroendocrine function, we have investigated the effects of the peptide on the release of anterior pituitary hormones in the rat. Both intravenous (300 μg) or intraventricular (2 to 15 μg) injection of NPY produced in gonadectomized male rats a significant and long-lasting decrease of plasma LH levels. A short duration stimulating effect on prolactin plasma levels was also observed after the intravenous but not after the intraventricular injection of NPY. Plasma levels of the other pituitary hormones were not significantly modified after NPY injection. When incubated in vitro with anterior pituitary cells in monolayer culture, NPY produced no significant change in release of pituitary hormones. Thus NPY seems to exert a selective effect on LH release. Since this effect can be observed after both intravenous and intraventricular injection, it might be hypothesized that NPY could affect LHRH release in two areas which lack blood-brain barrier: the organum vasculosum of the lamina terminalis (OVLT) which contains LHRH cell bodies and NPY fibers and the median eminence which contains both LHRH and NPY fibers. The effect on prolactin release needs to be carefully evaluated in different experimental conditions.  相似文献   

11.
Monitoring levels of mineral concentrations in animal tissues is important for assessing the effect of contamination on animal health and safety of animal origin products in human nutrition. This study evaluated the levels of certain trace elements (copper, zinc, iron, and manganese) in cattle from an industrial and mining region in the north of Spain (Asturias). Samples of 312 animals aged 9–12 mo were collected from the whole region and analyzed after acid digestion using atomic absorption spectrophotometry (AAS). The geometric mean concentrations obtained per wet weight for the liver, kidney, muscle, and blood were 34.3 mg/kg, 4.04 mg/kg, 1.65 mg/kg, and 0.651 mg/L for copper, respectively, and 38.5 mg/kg, 23.0 mg/kg, 47.0 mg/kg, and 2.44 mg/L for zinc, respectively. For iron, blood was not analyzed and results were 96.2 mg/kg, 105 mg/kg, and 56.0 mg/kg for the liver, kidney and muscle, respectively. For manganese, only the liver and kidney were analyzed, and the results were 3.11 mg/kg and 1.19 mg/kg, respectively. There was no evidence of an accumulation of toxic levels of trace metals in Asturian cattle. Females accumulated more iron in the liver (p<0.001, F 1,310=18.4) and the kidney (p<0.001, F 1,310=13.5) and more manganese in the liver (p<0.01, F 1,310=9.55) than males.  相似文献   

12.
Summary Unusual paracrystalline aggregates of microtubules which have not been described in any other mammalian species were observed in cultured anterior pituitary cells of normal chinchillas as well as in situ in the pituitary glands of these animals. These aggregates appeared as regularly arranged tubular structures in the longitudinal plane, and as a checkerboard pattern of closely and regularly packed microtubules when examined in transverse section. Supplementation with vinblastine, colcemide or colchicine in the culture medium did not change these structures morphologically. Each unit of tubules consisted of an outer wall or parellelogram profile and an inner wall composed of a single hexagonal doublet or in a figure 8 form. The outer wall of the parallelogram was 35×28 nm in length for both sides, while the diagonal of the inner wall was 18×28 nm. These paracrystalline aggregates of microtubules in the chinchilla pituitary cells are morphologically distinct from the paracrystalline assembly of cytoplasmic microtubules induced by vinblastine or other alkaloids.The function and significance of these paracrystalline aggregates in anterior pituitary cells of the chinchilla are uncertain.Supported by USPHS Grant HD 11826  相似文献   

13.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

14.
We have measured and compared several metallic elements and matrix metalloproteinases (MMPs) in saliva from patients with taste disorder and healthy subjects. Stimulated whole saliva was collected from 20 patients and 35 healthy subjects. Inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of metallic elements in saliva. Amounts of MMP-1, MMP-3, MMP-9 and IL-1alpha, IL-6 in saliva were measured using an enzyme-linked immunosorbent assay systems. Zinc in the serum was determined by flame atomic absorption spectrometry. Our results provide evidence that levels of zinc, manganese and the amount of MMP-3 in saliva are significantly decreased in the patients with taste disorder compared to the healthy subjects; Zn (p.p.b.): healthy subjects 79.8 +/- 42.6, patients 47.22 +/- 17.1, (P < 0.001), Mn (p.p.b.): healthy subjects 4.48 +/- 2.46, patients 2.78 +/- 1.23, (P < 0.004), MMP-3 (ng/ml), healthy subjects 0.820 +/- 0.417, patients 0.594 +/- 0.179 (P < 0.01). In contrast, copper is significantly increased in the patients; Cu (p.p.b.): healthy subjects 34.5 +/- 13.5, patients 45.9 +/- 20.8 (P < 0.049). These differences may be closely related with this disease. ICP-MS is an easy and accurate instrument for measurements of salivary metallic elements and may be useful in establishing a diagnosis of taste disorder.  相似文献   

15.
The levels of seven trace elements such as copper, iron, zinc, selenium, cadmium, chromium, and nickel were determined by graphite furnace-atomic absorption spectrometry in the cervical mucus of 45 women residing in Taiwan, Republic of China. These women were in good health and had no precancerous or cancerous lesions on their cervix. The women were separated into four age groups to establish if there was a relationship between the age of the subjects and the values of these elements in the cervical mucus. By one-way analysis of variance, significant differences in the selenium and nickel concentrations were found among the four age groups (p<0.05). The mean concentration of selenium in each age group was significantly higher for the older women. A significant correlation between age and selenium concentration was found by linear regression (r=0.23, p=0.00048). No significant differences among the concentrations of copper, iron, zinc, cadmium, and chromium were found among these four age groups (p>0.05). The results presented in this work may be considered as baseline values for these elements in the cervical mucus of healthy Taiwanese women for use as reference in studies on cervical diseases and tissue damage.  相似文献   

16.
Solar UV-B radiation increased to 20 % over ambient level at Madurai was given to cowpea (Vigna unguiculata L. cv. Pusa-152) seedlings sufficiently supplied by potassium (0.88 mM K2SO4) and K-deficient (0.05 mM K2SO4). Leaf mineral composition was significantly changed due to both increased UV-B radiation and K-deficiency imposed independently or jointly for 12 d. A severe reduction in 23 kDa chloroplast protein was seen only in seedlings encountered combined stress. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
Multielemental detection using Instrumental Neutron Activation Analysis (INAA) and Proton-Induced X-Ray Emission (PIXE) of drinkable water of Florence (Italy) is described. The concentrations of 52 elements were measured. No chemical treatment was performed on the samples, before or after irradiation. On the basis of an appropriate combination of the two analytical techniques, a procedure for aluminum determination was developed. Results are briefly discussed from a methodological point of view.  相似文献   

18.
In liver cirrhosis, liver tissue becomes progressively substituted by fibrosis, ultimately leading to architectural distortion, liver circulatory changes, and liver failure. Some data support the hypothesis that protein undernutrition may play a role in the development and progression of nonalcoholic liver cirrhosis and that this progression is at least partially mediated by changes in glutathione peroxidase (GPX), superoxide dismutase (SOD), and other antioxidative systems, leading to an increase in lipid peroxidation. We analyzed the effects of protein deficiency on liver Cu, Fe, Zn, Mn, and Se in carbon tetrachloride (CCl4)-induced liver cirrhosis, the relation of protein undernutrition and these trace elements with the activity of some hepatic antioxidative enzymatic mechanisms, and the relation of all of them with morphological and biochemical changes in 40 male adult Sprague-Dawley rats divided in four groups. Liver cirrhosis was induced by intraperitoneal injection of CCl4 to 10 rats fed a 2% protein diet and another 10 fed a 18% protein control diet; two further groups included rats without cirrhosis fed the 2% protein and the 18% protein diets. The study period lasted 6 wk. GPX, SOD, and lipid peroxidation products as well as Zn, Cu, Mn, Se, and Fe were determined in liver samples. We found that liver GPX and Se were reduced in the cirrhotic animals, especially in the low-protein-fed ones, protein deficiency, but not cirrhosis, exerting the main effects. A close correlation was found between liver GPX and serum albumin and weight loss and an inverse one among GPX and hepatocyte ballooning, liver fibrosis, and fat, histomorphometrically determined. These results suggest a pathogenetic role of decreased GPX in the progression of liver disease, which may become enhanced by concomitant protein undernutrition. In addition to iron, the levels of which were increased in the malnourished rats, no differences were found regarding the other trace elements, SOD activity, and lipid peroxidation products.  相似文献   

19.
Serum levels of selenium, copper, and zinc were systematically determined in healthy subjects of the Lisbon population. The sample consisted of 183 blood donors of both genders who were divided into two age groups: 20–44 and 45–70 yr of age; relationships with gender, age, the lipid profile, and tobacco consumption were investigated. In the female group, the intake of oral contraceptives and pregnancy were considered for the youngest women, and hormonal replacement therapy (HRT) was taken into account for the oldest ones. Serum concentrations of these elements were in the same range as those found for populations of other European countries. Differences between genders were observed for the three elements studied, with serum selenium and zinc concentrations higher in men and copper levels higher in women. Age-dependent differences were found for selenium: The oldest subjects (regardless gender) presented the highest concentrations of selenium in serum as further demonstrated by the positive correlation with age. In both pregnant and contraceptive-using women, copper was greatly increased, confirming the influence of estrogen status and/or oral contraceptive intake on increased serum copper levels. However, in postmenopausal women, HRT did not significantly affect serum copper levels. Selenium, copper, and zinc status were not different between normolipidemic and hyperlipidemic subjects for the same gender and age range, but selenium levels tended to increase with hyperlipidemia when considering the whole group of subjects. With respect to the lifestyle, higher serum zinc levels were found in tobacco-consuming men. Albumin serum levels were similar for all considered subgroups, except for the pregnant women, for whom a decrease in this parameter was observed. The present study allowed one to obtain reference values for this healthy group of population, which will serve for a comparative study with groups having pathological conditions, such as cardiovascular disease.  相似文献   

20.
Summary After an exposure of 24 h to synthetic LHRH (100 ng/ml) in vitro, the anterior pituitaries of 4-day-old rats show a notable loss of immunoreactive material in most LH cells in males, but not in females. When radioimmunoassayed without incubation, the pituitary LH content of 4-day-old female rats is 2.8 times higher than that of males of the same age. LHRH treatment stimulates a higher rate of LH discharge in females than in males, but if LH release is expressed as a percentage of the initial pituitary LH content, there is no apparent difference. In both sexes, more than 70% of the initially stored LH is discharged into the medium after 24 h of LHRH stimulation. In males, this discharge produces a pronounced depletion, but in females, the pituitary still contains 78.2% of the initial LH content despite the large amount of hormone released.From these results, it is concluded that in newborn rats the LH synthetic rate in females is higher than that in males. This high synthetic activity, together with the large store of LH, may explain why prolonged LHRH treatment fails to cause LH depletion in females. At 4 days of age LHRH had no stimulatory effect on pituitary synthesis of LH in either sex.  相似文献   

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