Stopové prvky jsou v lidském těle součástí řady důležitých funkcí. Svůj nepochybný význam mají i pro vývoj skeletu od fetálního období s podílem na novotvorbě kosti, a v dospělosti pak v udržení její integrity. Některé stopové prvky mají na kost efekt protektivní (zinek), jiné naopak toxický (kadmium, chrom, kobalt). Měření koncentrací stopových prvků v tělních tekutinách (krev a moč) a ve tkáních (vlasy a kost) umožní identifikovat jedince ohrožené osteoporotickými frakturami v důsledku nutričního deficitu. Článek podává přehled součas- ných znalostí o významu stopových prvků pro fyziologii skeletu.
Trace elements are involved in a number of important functions in the human body. They are of undoubted importance for the development of the skeleton from the foetal period onwards, contributing to new bone formation, and in adulthood to the maintenance of its integrity. Some trace elements have a protective effect on the bone (zinc), others have a toxic effect (cadmium, chromium, cobalt). Measurement of trace element concentrations in body fluids (blood and urine) and tissues (hair and bone) will allow identification of individuals at risk of osteoporotic fractures due to nutritional deficiencies. This article provides current knowledge on the importance of trace elements for skeletal physiology.
- MeSH
- kostra * fyziologie růst a vývoj MeSH
- lidé MeSH
- nutriční nároky MeSH
- stopové prvky * krev metabolismus moč nedostatek toxicita MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Today, it is proven that the contaminated urban soils are hazardous for the human health. Soil substrates of playgrounds call for special research as they are places where children are directly exposed to soil contaminants. Therefore, the objective of this work was to measure the pseudo-total contents and bioaccessibility of several metals and metalloids (As, Bi, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, Sn, V, Zn) in two grain sizes (< 150 μm and < 50 μm) of playground soils in Bratislava city (the capital of Slovakia). The content of metal(loid)s in the soils was controlled by a number of factors, with their increased contents (above 75% percentile or higher) at sites influenced by point sources of pollution (industry and agriculture) or at old sites located in the city centre. Cobalt, Cr, Fe, Mn, Ni and V had relatively uniform contents in soils compared to the other elements. As regression modelling with a categorical variable confirmed, the age of urban areas influenced the accumulation of As, Bi, Cd, Cu, Hg, Pb, Sb and Sn in playground soils. Exploratory statistical techniques with compositionally transformed data (principal component analysis, cluster analysis and construction of symmetric coordinates for correlation analysis) divided trace elements into the two main groupings, Co, Cr, Fe, Mn, Ni, V and Bi, Cd, Cu, Hg, Pb, Sb, Sn, Zn. Median concentrations of the elements in smaller soil grains (< 50 μm) were significantly higher than in coarser grains (< 150 μm). Cobalt, Cu, Mn, Pb, Sn and Zn had significantly higher bioaccessible proportions (% of the pseudo-total content) in < 50 μm soil size than in < 150 μm; however, the same order of bioaccessibility was achieved in both grain sizes. The highest bioaccessibility had Cd, Cu, Pb and Zn (~ 40% and more), followed by Co, As, Mn, Sb (18-27%), Hg, Ni, Sn (10-12%) and finally Cr, Fe and V (less than 4%). The hazard index and carcinogenic risk values were higher in < 50 μm than in < 150 μm and significantly decreased in the two soil sizes when the bioaccessibility results were included in the health hazard calculation.
- MeSH
- biologická dostupnost MeSH
- dítě MeSH
- karcinogeny analýza MeSH
- kovy analýza farmakokinetika MeSH
- látky znečišťující půdu analýza farmakokinetika toxicita MeSH
- lidé MeSH
- monitorování životního prostředí metody MeSH
- polokovy analýza farmakokinetika MeSH
- půda chemie MeSH
- stopové prvky analýza farmakokinetika toxicita MeSH
- velikost částic MeSH
- velkoměsta MeSH
- veřejné parky MeSH
- vystavení vlivu životního prostředí škodlivé účinky analýza MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Slovenská republika MeSH
- velkoměsta MeSH
The normotensive (Wistar) and spontaneously hypertensive (SHR) rats were examined to assess the response of the organism to selenium (Se) overdose. Moreover, the effect of zinc (Zn) and vitamin E, i.e. dietary components interacting in many biochemical processes with Se, on the Se uptake was evaluated. The control group was fed an untreated diet, and the diets of two other groups were overdosed with Se in the form of sodium selenite (9 mg/kg) and supplemented with Zn (13 mg/kg). Two experimental groups were fed a diet supplemented with Zn (13 mg/kg) and Se at an adequate level (0.009 mg/kg); a half of the animals was supplemented with vitamin E. The results showed significant differences in the Se contents between the rat strains in case of Se-overdosed groups, where in the liver and kidney tissue Se contents of SHR rats exceeded 3- and 7-fold the normotensive ones. The Se uptake was altered by the vitamin E; no effect of Zn was observed. Activities of antioxidant enzymes were determined in the animal tissues indicating different patterns according to rat strain, tissue analysed, and administered Se dose. Thus, Se overdose, for instance, via an incorrectly prepared dietary supplement, can result in serious imbalances of the biochemical status of the animals.
- MeSH
- antioxidancia aplikace a dávkování terapeutické užití MeSH
- kombinovaná farmakoterapie MeSH
- krysa rodu rattus MeSH
- potkani inbrední SHR MeSH
- potkani inbrední WKY MeSH
- potravní doplňky MeSH
- předávkování léky farmakoterapie metabolismus MeSH
- selen aplikace a dávkování toxicita MeSH
- stopové prvky aplikace a dávkování terapeutické užití toxicita MeSH
- vitamin E aplikace a dávkování terapeutické užití MeSH
- zinek aplikace a dávkování terapeutické užití MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Urban particulate matter (PM) can affect green plants either via deposition on the above-ground biomass, where the contaminants can penetrate the leaf surface, or indirectly via soil-root interaction. This experiment assessed the potential risk of PM-derived risk elements contained in vegetables. The bioavailable portions of arsenic (As), cadmium (Cd), iron (Fe), and zinc (Zn) in leafy vegetables amended by PM via soil and/or foliar application were investigated in a model pot experiment, in which lettuce and chard were cultivated. RESULTS: By using the physiologically based extraction test simulating in vitro human digestive processes in the stomach and small intestine, the bioavailable portions of toxic elements from PM-amended plant biomass were extracted. Extractable portions of elements by a simulated gastric solution from biomass decreased for lettuce in the order Zn > Cd > As > Fe; while for chard, the order was As > Zn > Cd > Fe. No significant effects of PM physical fractions or soil were observed. CONCLUSIONS: Although the bioavailable element portions in the PM samples were lower compared to plants, the bioavailable element contents in foliar PM-amended plant leaves exceeded the control and soil PM amendment levels, even after biomass washing.
- MeSH
- arsen analýza MeSH
- Beta vulgaris chemie MeSH
- biologická dostupnost MeSH
- biomasa MeSH
- dieta MeSH
- kadmium analýza MeSH
- kořeny rostlin MeSH
- látky znečišťující půdu analýza MeSH
- látky znečišťující vzduch analýza MeSH
- lidé MeSH
- listy rostlin * MeSH
- pevné částice analýza MeSH
- půda chemie MeSH
- salát (hlávkový) chemie MeSH
- stopové prvky analýza toxicita MeSH
- tenké střevo MeSH
- žaludek MeSH
- železo analýza MeSH
- zinek analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Changes of amino acid concentrations (glutamic acid, glutamine, asparagine, aspartate, proline, tryptophan, alanine, glycine, valine and serine), gas-exchange parameters (net photosynthetic rate, transpiration rate, stomatal conductance and intercellular CO(2) concentration) and nitrate levels in Lactuca serriola L. under airborne particulate matter (PM) contamination reported here reveal their role in plant chronic stress adaptation. Results of the pot experiment confirmed the toxic effect of trace elements present in PM for lettuce. PM applied to soil or on the lettuce leaves were associated with the strong inhibition of above-ground biomass and with the enhancement of plant trace element contents. The significant changes of amino acid levels and leaf gas-exchange parameters of the plants showed strong linear dependences on PM contamination (R(2)=0.60-0.99). PM application on leaves intensified toxic effect of trace elements (As, Pb, Cr and Cd) originating from PM by shading of the leaf surface. The plant accumulation of nitrate nitrogen after PM contamination confirmed to block nitrate assimilation.
- MeSH
- biomasa MeSH
- dusičnany metabolismus MeSH
- dusík metabolismus MeSH
- fotosyntéza účinky léků MeSH
- fyziologický stres MeSH
- fyziologie rostlin účinky léků MeSH
- látky znečišťující půdu analýza toxicita MeSH
- látky znečišťující vzduch analýza toxicita MeSH
- listy rostlin účinky léků metabolismus MeSH
- pevné částice analýza toxicita MeSH
- půda chemie MeSH
- rostliny účinky léků metabolismus MeSH
- salát (hlávkový) metabolismus MeSH
- stopové prvky analýza toxicita MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: The objective of the study was to assess the metabolic risk of excessive dietary iodine intake in ewes and neonatal lambs. DESIGN: Pregnant Šumava ewes received an experimental diet containing 3.1 mg iodine per kg of dietary dry matter in Group A (control, n=13, 6 ewes and 7 lambs) and 5.1 mg iodine per kg of dietary dry matter in Group B (experimental, n=12, 6 ewes, 6 lambs) for eight months. Iodine was administered to ewes as calcium iodate. TSH in blood serum; TT3, TT4, fT3, and fT4 in blood plasma were examined in both groups of ewes and lambs to assess the risks of iodine intake above the permitted limit, as it applies to thyroid gland activity. RESULTS: Group B ewes showed a significant increase in TSH and TT4 only on day 1 after parturition. The highest values of TT4, TT3, and fT3 in lambs were recorded on day 1 after birth. The lowest values of fT3 and fT4 in lambs were measured on day 60 after birth with no differences observed between the groups. In lambs of Group B the lower concentration of TSH until day 3 after birth was followed by a significant increase from day 10 after birth. CONCLUSION: Our results indicate a risk of postnatal hypothyroidism among lambs from pregnant and lactating ewes having a high iodine intake.
- MeSH
- hypotyreóza krev chemicky indukované MeSH
- jod toxicita MeSH
- laktace MeSH
- náhodné rozdělení MeSH
- novorozená zvířata MeSH
- ovce MeSH
- štítná žláza účinky léků fyziologie MeSH
- stopové prvky toxicita MeSH
- těhotenství MeSH
- thyreotropin krev MeSH
- thyroxin krev MeSH
- trijodthyronin krev MeSH
- zpožděný efekt prenatální expozice krev chemicky indukované MeSH
- zvířata MeSH
- Check Tag
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The aim of solidification of ashes is to reduce the bioavailability of toxic heavy metals. The review focuses on comparison of water leachability of raw ashes and ashes solidified with cement. The leachates of raw ashes were toxic due to increased concentrations of trace elements, in particular Cd, As, and Se. On solidification leachability of most of the toxic metals significantly decreased, but their ecotoxicity did not decrease to the expected extent.
- MeSH
- antioxidancia * MeSH
- biologická dostupnost MeSH
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- mladiství MeSH
- náhodné rozdělení MeSH
- selen * nedostatek škodlivé účinky terapeutické užití MeSH
- selenomethionin MeSH
- selenoproteiny fyziologie MeSH
- stopové prvky nedostatek toxicita MeSH
- výživové doporučené dávky MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- práce podpořená grantem MeSH
- MeSH
- finanční podpora výzkumu jako téma MeSH
- látky znečišťující životní prostředí farmakokinetika toxicita MeSH
- lišky metabolismus růst a vývoj MeSH
- sperma metabolismus účinky léků MeSH
- spermie patologie účinky léků MeSH
- stopové prvky farmakokinetika toxicita MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
