共查询到20条相似文献,搜索用时 15 毫秒
1.
A. -L. Mäkelä W. -C. Wang M. Hämäläinen V. Näntö P. Laihonen H. Kotilainen L. -X. Meng P. Mäkelä 《Biological trace element research》1995,47(1-3):289-298
To study the possible pollution of natural waters by selenium added to agricultural fertilizers, water selenium concentrations
were determined in lakes and ground water pools during the year 1992, when the enrichment of fertilizers by selenium had continued
for 8 yr. Water samples were preconcentrated by evaporating, and selenium concentrations were analyzed fluorometrically using
the dye 2,3-diaminonaphthalene after wet digestion. In lake water samples from 13 lakes, no significant correlations were
found between selenium and pH, chlorophyll A, total nitrogen, or phosphorus. Agriculturally affected and nonaffected lakes
had no differences in their selenium concentrations. In the lakes that were surrounded by cultivated fields mean water selenium
was 83.4 ng/L (range: 75.2–93.4 ng/L,n=9). Correspondingly, in lakes situated in forests without agricultural surroundings, mean water selenium concentration was
76.5 ng/L (range: 51.2–110 ng/L,n=3). Only one lake in the close vicinity of a coal power plant had a high water selenium concentration (mean 272 ng/L).
In ground water samples, there was a big variation in selenium levels between different pools, the levels varying between
33 and 260 ng/L. This variation may partly be explained by different selenium concentrations of the bedrock and sediments.
However, simultaneous increase of total nitrogen, phosphorus, and selenium levels in consecutive samples from some ground
water pools indicates leaching of selenium from the fertilizers into the ground water in certain areas. 相似文献
2.
A. A. Goede 《Biological trace element research》1993,39(2-3):177-190
The distribution of selenium in a marine wader, the Oystercatcher (Haematopus ostralegus) is given by the levels in 15 tissues and plasma. Red blood cells (RBC) contain the highest level (23 mg/kg dry wt) followed
by liver, lung, and kidney (17–19 mg/kg). Most other tissues range from 3–10 mg/kg. The average kidney and liver concentrations
of the Oystercatcher belong to the concentrations characteristic in birds. However, the Oystercatcher's tissue selenium concentrations
are in general four-to fivefold mammalian levels, but in liver and lung, 11- to 13-fold and in the RBC, 12- to 33-fold. The
selenium plasma and RBC levels of the Oystercatcher vary during the year from 280 to 410 μg/L and 13 to 30 mg/kg dry wt, respectively;
the plasma concentrations are positively correlated with the RBC selenium concentrations. An overview of literature data shows
that the selenium kidney and liver concentrations of birds do not vary with geographical latitude and size (length) of the
birds. In species of the ordersCharadriiformes andProcellariiformes, high selenium kidney, and to a lesser extent liver, concentrations may occur. A function of selenium in antioxidation is
suggested. 相似文献
3.
Josef Kiem 《Biological trace element research》1988,15(1):83-88
Blood and its main components are commonly used to detect states of selenium deficiency. In order to examine whether human
platelets are able to provide better or additional information, improvements analytical method resulted in surprisingly narrow
normal ranges for selenium and other mineral elements using neutron activation analysis (NAA) and atomic absorption spectrophotometry
(AAS), and controlling thermal neutron flux, (n,γ)-cross sections, mean platelet wet wt, and water fraction of the platelets.
Previously reported selenium concentrations in platelets on wet wt basis in the order of 500 ng/g—half of which had been found
to derive from early bone marrow precursors using74Se-selenite—were reproduced by NAA and AAS. However, with the new analytical method the selenium concentrations showed a narrower
normal range than that of plasma. Moreover, platelet selenium did not in all cases correlate with plasma selenium. Cellular
tissues such as platelets should, therefore, help to detect latent states of selenium deficiency. 相似文献
4.
Generational differences in selenium status of women 总被引:3,自引:0,他引:3
In this cross-sectional study of three generations of women, daughters (19–26 yr), mothers (40–58 yr) and maternal grandmothers
(67–84 yr) from the same 10 families in central Ohio were studied to determine the effect of life-cycle differences, including
estrogen status, on selenium status. Plasma and red blood cell (RBC) selenium and glutathione peroxidase (GPx) activities
were determined and typical dietary selenium intakes were calculated from food-frequency questionnaires. Selenium status was
lowest in the oldest generation. Plasma selenium of daughters and grandmothers were significantly lower than those of mothers,
and plasma GPx and RBC selenium of grandmothers were also lower than those of the mothers. A positive correlation (r=0.42, p<0.04) was found between plasma estrogen and plasma selenium concentrations. Selenium intakes of all groups were adequate
and no differences in selenium intakes were found among groups. The results of this study indicate that selenium status fluctuates
during the female life cycle and is related to estrogen status. 相似文献
5.
Lars Björkman Brita Palm Magnus Nylander Monica Nordberg 《Biological trace element research》1994,40(3):255-265
Concentration of mercury and selenium were analyzed in tissue fractions of human kidney cortex samples from seven autopsy
cases. Total mercury content ranged between 0.3–9.0 nmol Hg/g wet wt. Between 27–61% of the total mercury was found in the
105,000g supernatant of the tissue homogenate from six cases. In kidney cortex from the seventh case, a deceased dentist with
the highest concentration of mercury, only 3% of the total mercury was found in the 105,000g supernatant and about 88% in
a SDS-insoluble fraction. In this fraction the molar ratio between mercury and selenium was close to 1∶1. This study supports
results from previous animal studies and indicates that mercury in human kidney cortex could be deposited in forms with different
solubility. It could be of importance to speciate different forms of mercury in tissues according to solubility and association
to selenium when interpretations of mercury concentrations are made. 相似文献
6.
Antti Aro Jorma Kumpulainen Georg Alfthan Anatoly V. Voshchenko Vladimir N. Ivanov 《Biological trace element research》1994,40(3):277-285
The selenium concentration in foods grown and consumed and in plasma, red blood cells, and toenails of people living in the
district of Chita in the transbaikalian part of Russia were studied in August 1991. Preliminary results from the area have
suggested low selenium intakes and the possible occurrence of cardiomyopathy (Keshan disease) in the population. A low selenium
concentration in foods grown locally was found: mean selenium concentration in wheat grains was 1, 5, and 28 μg/kg, respectively,
in three villages studied, that of oats was beween 3–6 μg/kg, and of cow's milk 10–27 μg/kg dry matter. The selenium concentration
of bread was considerably higher, between 87–337 μg/kg dry wt, presumably because wheat imported from the US had been used
for baking. Occasional samples of pork, beef, and mutton contained between 32–318 μg selenium/kg dry wt. Low selenium concentrations
were observed in samples of soil and river water. The mean plasma selenium concentration of 52 persons was 1.02 μmol/L, including
33 children and 19 adult subjects. The selenium concentrations in red blood cells and toenails were 1.95 μmol/L and 0.61 mg/kg,
respectively. No symptoms of heart disease caused by selenium deficiency were observed. It is concluded that the selenium
status of people was fairly good thanks to the contribution to dietary intake of imported wheat with a high selenium content.
As the selenium concentration was very low in foods grown in the area, the selenium intake of the population will be reduced
to a very low level if only locally produced foods are consumed. 相似文献
7.
Bogumiła Pilarczyk Diana Hendzel Renata Pilarczyk Agnieszka Tomza-Marciniak Barbara Błaszczyk Marta Dąbrowska-Wieczorek Małgorzata Bąkowska Ewa Adamowicz Tomasz Bujak 《European Journal of Wildlife Research》2010,56(5):797-802
The aim of this study was to determine liver and kidney concentrations of selenium in wild boars from the northwest part of
Poland, depending on season of the year, age, sex, and body weight. Altogether, samples of livers and kidneys from 172 wild
boars that were shot in 2005–2008 were investigated. Liver and kidney concentrations of selenium were determined using spectrofluorometric
method. In all the animals studied, selenium concentration was several times lower in the liver than in the kidneys. Selenium
concentration averaged 0.19 μg/g wet weight (w.w.) in the liver and 1.20 μg/g w.w. in kidneys. The present study showed that
season (P ≤ 0.05), age (P ≤ 0.01), and body weight (P ≤ 0.01) have a significant effect on selenium concentration in the liver of wild boars. Liver selenium concentration was
the highest in spring (0.23 μg/g w.w.) and the lowest in autumn (0.16 μg/g w.w). Young animals (up to 1 year of age) and those
with the lowest body weight (up to 20 kg) were characterized by a slightly lower selenium concentration in the liver compared
to older and heavier animals. No significant differences were found in organ selenium concentration between males and females.
According to biochemical criteria for the diagnosis of selenium deficiency in pig liver, which were used to evaluate selenium
concentration in the liver of wild boars, no individuals were found to have optimal levels. Considering that in Se deficiency
higher selenium concentrations are found in kidneys than in the liver, it can be presumed that the wild boars had Se deficiency.
However, this is difficult to state conclusively because there are no reference values for this species. 相似文献
8.
Gürgöze MK Olçücü A Aygün AD Taskin E Kiliç M 《Biological trace element research》2006,111(1-3):23-29
In the present study, the serum and hair levels of zinc, selenium, and copper were determined in children with iron-deficiency
anemia (IDA). A total of 52 anemic children aged 1–4 yr constituted the study group. Fortysix healthy children acted as controls.
The copper and zinc levels were measured with an atomic absorption spectrophometer. Serum and hair selenium was determined
by a spectroflourometric method. The serum zinc and selenium concentrations in the IDA group were found to be significantly
lower and serum copper significantly higher than those in the controls (p<0.05). Lower iron, zinc, and selenium concentrations (p<0.001) but not copper were found in hair (p>0.05). 相似文献
9.
Our purpose in this study was to investigate the protective effects of selenium and vitamin E on the blood–brain barrier (BBB)
permeability in rats with convulsion under hyperthermic conditions. To eliminate the effect of sex on BBB, we performed our
study on 4- to 5-week-old prepubertal rat pups. Evans-blue was used as a BBB tracer. Convulsions were induced by administration
of i.p. pentylenetetrazol. In the selenium group, 4 ppm selenium was added to the drinking water for 4–5 weeks. Vitamin E
was administered at 700 mg/kg ip. It was shown that the convulsions, both under normothermic and hyperthermic conditions,
caused widespread increase in the BBB permeability (p < 0.05). In addition, a significant difference was observed among female and male rats (f [1, 102] = 6.387, p < 0.05). In convulsions under normothermic conditions, there was a further increase in the BBB permeability (F[3, 102] = 43.534, p < 0.001) and a greater increase of permeability in males compared to females (F[1, 102] = 6.387, p < 0.05). Selenium and vitamin E significantly decreased the BBB destruction caused by convulsions under hyperthermic conditions
in males (p < 0.05). Treatment with selenium or vitamin E has beneficial effects on the BBB breakdown during convulsions. But gender
differences are very important in BBB permeability under pathological conditions and antioxidant treatments. 相似文献
10.
As part of the general host response to coxsackievirus B3 (CB3) infection, the concentration of essential and nonessential
trace elements changes in different target organs of the infection. Essential (e.g., Se) and nonessential (e.g., Hg) trace
elements are known to interact and affect inflammatory tissue lesions induced by CB3 infection. However, it is unknown whether
these changes involve the brain. In the present study, the brain Hg and Se contents were measured through inductively coupled
plasma-mass spectrometry and their distribution investigated by means of nuclear microscopy in the early phase (d 3) of CB3
infection in normally fed female Balb/c mice. Because of the infection, the concentration of Hg (4.07±0.46 ng/g wet wt) and
Se (340±16 ng/g wet wt) in the brain increased twofold for Hg (8.77±1.65 ng/g wet wt, p<0.05) and by 36% for Se (461±150 ng/g wet wt, ns). Nuclear microscopy of brain sections from mice having elevated Se and
Hg concentrations failed to find localized levels of the elements high enough to make detection possible, indicating approximately
homogeneous tissue distribution. Although the pathophysiological interpretation of these findings requires further research,
the increase of Hg in the brain during infection might have an influence on the pathogenesis of the disease. 相似文献
11.
Kłapcińska B Poprzecki S Danch A Sobczak A Kempa K 《Biological trace element research》2005,108(1-3):1-15
The selenium status and the relationship of whole-blood selenium and plasma homocysteine are reported for healthy human subjects
living in Upper Silesia. A total of 1063 individuals (627 male and 436 female) examined for whole-blood selenium were subdivided
into six groups according to age; the youngest included adolescents (n=143) aged 10–15 yr, and the oldest were centenarians (n=132). The mean Se content was relatively low (62.5±18.4 μg/L), and it tended to be higher in men (65.9±17.2 μg/L) than in
women (57.5±18.9 μg/L). Selenium levels appeared to be age dependent, as the highest values were observed in young and middle-age
adults (21–40 yr), whereas they were significantly lower in adolescents and in the elderly. In more than 40% of apparently
healthy adults (aged 21–69 yr), the Se concentration was within the range 60–80 μg/L (i.e., below the lower limit of the nutritional
adequacy range [80 μg/L]). A significant inverse correlation between whole-blood selenium and plasma total homocysteine was
detected in a smaller population sample of middle-aged and elderly persons (n=204). 相似文献
12.
Wayne Chris Hawkes Calvin C. Willhite Kimberly A. Craig Stanley T. Omaye Douglas N. Cox Wai Nang Choy Andrew G. Hendrickx 《Biological trace element research》1992,35(3):281-297
Forty pregnant long-tailed macaques were treated daily for 30 d with 0, 25, 150 or 300 μg selenium as L-selenomethionine/kg
body weight. Erythrocyte and plasma selenium and glutathione peroxidase specific activities, hair and fecal selenium, and
urinary selenium excretion were increased by and were linearly related to L-selenomethionine dose. Hair selenium was most
sensitive to L-selenomethionine dose, with an 84-fold increase in the 300 μg selenium/(kg-d) group relative to controls (r=0.917). Daily urinary selenium excretion (80-fold,r=0.958), plasma selenium (22-fold,r=0.885), erythrocyte selenium (24-fold,r=0.920), and fecal selenium (18-fold,r=0.911) also responded strongly to L-selenomethionine. Erythrocyte and plasma glutathione peroxidase specific activities increased
154% and 69% over controls, respectively. Toxicity was associated with erythrocyte selenium >2.3 μg/mL, plasma selenium >2.8
μg/mL, and hair selenium >27 μg/g. Plasma, erythrocyte, and hair selenium concentrations may be useful for monitoring and
preventing the toxicity of L-selenomethionine administered to humans in cancer chemoprevention trials. 相似文献
13.
In order to investigate the selenite metabolism in the anterior pituitary and compare it with other endocrine organs, rats
were injected intraperitoneally with75Se sodium selenite (5 mg/kg). The rats were whole body counted shortly after injection and recounted just before sacrifice,
which was performed 2, 24, 48 h, and 4, 10, 20, 30, 40, 60, and 80 d after injection. Besides the anterior pituitary, the
selenium content was also estimated in the thyroid gland, testis, adrenals, liver, kidney, and blood. The maximum selenium
content was observed in all organs 2 h after injection, at which time the anterior pituitary contained 2.9 μg/g wet wt, compared
to 13.5 μ/g wet wt in liver and .6 μg/mg wet wt in testis.
The excretion of selenite from the anterior pituitary resembled that seen in most other organs investigated, i.e., an initial
rapid excretion and a slower secondary phase resembling a first order reaction. Practically all selenium was excreted by 60
d after injection. 相似文献
14.
In order to evaluate hydrocarbon inputs to Crater Lake from anthropogenic and natural sources, samples of water, aerosol,
surface slick and sediment were collected and analyzed by gas chromatography-mass spectrometry (GC-MS) for determination of
their aliphatic and aromatic hydrocarbon concentrations and compositions. Results show that hydrocarbons originate from both
natural (terrestrial plant waxes and algae) and anthropogenic (petroleum use) sources and are entering the lake through direct
input and atmospheric transport. The concentrations of petroleum hydrocarbons range from low to undetectable. The distributions
and abundances of n-alkanes, polycyclic aromatic hydrocarbons (PAH) and unresolved complex mixture (UCM) from petroleum are similar for all surface
slick sampling sites. The estimated levels of PAH in surface slicks range from 7–9 ng/m2 which are low. Transport of petroleum-derived hydrocarbons from the lake surface has resulted in their presence in some sediments,
particularly near the boat operations mooring (total petroleum HC = 1440 μg/kg, dry wt. compared to naturally derived n-alkanes, 240 μg/kg, dry wt.). The presence of biomarkers such as the tricyclic terpanes, hopanes and steranes in shallow
sediments further confirms petroleum input from boat traffic. In the deep lake sediments, petroleum hydrocarbon concentrations
were very low (16 μg/kg, dry wt.). Very low concentrations of PAH were detected in shallow sediments (17–40 μg/kg at 5 m depth
near the boat operations) and deep sediments (3–15 μg/kg at 580 m depth). The individual PAH concentrations in sediments (μg/kg
or ppb range) are at least three orders of magnitude less than reported threshold effects levels (mg/kg or ppm range, test
amphipod Hyalella azteca). Therefore, no adverse effects are expected to occur in benthic biota exposed to these sediments. Boating activities are leaving a detectable level of petroleum in surface waters and lake sediments but these concentrations are very low. 相似文献
15.
Variation in the nitrotoxin concentration of 13 species ofAstragalus (fabaceae) over a 6-year period
U. M. Cowgill 《Biological trace element research》1991,31(2):111-118
The purpose of this study was to examine the variation in nitrite production in the leaves of various species ofAstragalus over a 6-y period. It was discovered that in drought years the nitrate concentration in leaves was consistently higher than
in wet years or those of edequate moisture. Among the plant examined,A. Hallii contained the greatest quantity in drought years (30–35 mg NO2/g leaf, dry wt basis) andA. aesclepiadoides had no detectable amounts in wet years. A two-way analysis of variance showed NO2 concentrations to be significantly different (p<0.0001) in the two climatic years. 相似文献
16.
K. Mengübaş N. A. Diab G. Gökmen O. Y. Ataman A. Cavdar Ş. Cin 《Biological trace element research》1996,54(2):163-172
Selenium concentrations, in blood plasma, red blood cells hair of 61 healthy children, ages 0–14 yr, were determined using
hydride generation atomic absorption spectrometry. Starting from late lactation period, selenium concentrations in all these
matrices were found to be increasing with age. A good correlation was found between erythrocyte and plasma, hair and plasma,
and hair and erythrocyte selenium concentrations. Although plasma, erythrocyte, and hair selenium concentrations of girls
seemed to be higher than that of boys (only in erythrocytes), selenium concentrations of girls were found to be significantly
(p<0.002) higher than that of boys, 71±9 ng/mL, vs 65±10 ng/mL, respectively. Selenium status of Turkish children is found to
be lower than that found in the literature; marginal selenium deficiency could be important in the development of some selenium
deficiency could be important in the development of some selenium deficiency related diseases. There is a need for extension
of this study to healthy children from different regions in Turkey and to different disease states. 相似文献
17.
Mireia Tondo Juan Moreno Mercedes Casado Nuria Brandi Cristina Sierra Maria A. Vilaseca Aida Ormazabal Rafael Artuch 《Neurochemical research》2010,35(8):1290-1293
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
18.
The liver of Hooded Seal (Cystophora cristata) consists of six lobes of unequal sizes. Extensive sampling by means of cutout samples covering the depth horizon 2–30 mm
below liver surface indicates that the liver may be considered homogeneous as to concentrations of zinc, cadmium, mercury,
and selenium (residuals of overall mean compatible with normality, the all-organ variance negligibly in excess of within-lobe
variance). Mercury and selenium are present in equimolar concentrations. Cutout samples have mercury and selenium concentrations
respectively c. 17 and 8% (dry weight basis) above those of homogenates of the same lobe. The apparent dilution of mercury
and selenium is tentatively attributed to coarse blood vessels and bile ducts abundantly present in the homogenate but almost
absent from the cutouts. 相似文献
19.
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
20.
Eduard Kühn Rudi Van Cauwenbergh Leo Huybrechts Hendrik Deelstra 《Biological trace element research》1992,32(1-3):289-292
Plasma concentrations of cGH, T3, and T4 were not different between dwarf and normal broiler breeders. Normal hens had a liver selenium content of 710±35 ng/g, and
dwarf hens 656 ±nine ng/g (n=8). Following injections into a wing vein of different doses (1.5, 3, 6, 12, and 24 μg/kg) of the hypothalamic hormone TRH,
GH was increased after 15 min. This effect seemed to last longer in dwarf chickens. Plasma concentrations of T3 increased significantly 1 h after TRH in normal hens, but TRH was ineffective in raising T3 levels in dwarf animals. The selenium content of livers obtained following decapitation after 2 h was also increased in normal
hens up to 902±42 ng/g using the highest dose of TRH (24 μg/kg). This seemed not to be the case for dwarf animals. A much
smaller. number of hepatic cGH receptors was also found in dwarf hens, whereas the affinity of the hepatic GH receptor was
not influenced by the genotype. It is concluded that the sex-linked dwarf hens are unable to increase their hepatic T4 into T3 conversion following a TRH challenge probably because of a deficiency in hepatic GH receptors. The lower content of selenium
in dwarfs and their inability to increase its uptake after TRH seem therefore to support the hypothesis that selenium has
a direct role in the activity of the 5′-deiodinase complex. 相似文献