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Following the Czernobyl accident, an epidemiologic study was undertaken in which the daily iodine intake was estimated in 15% of the population studied. Iodine excretion was measured in single morning urine specimens. The iodine content was also assessed in the water form wells and in cow-milk at farms in randomly chosen villages in the region of Krynica and Nowy Sacz. On the basis of a 24-hour diet recall, the mass of each food product consumed daily was estimated for 483 persons in the Kraków voivodship (14.4% of the total population) and for 397 persons in the Nowy Sacz voivodship (15.8% of the total population). Using this data, the nutrient content of the daily diet was calculated for each studied individual. Measurements of iodine content in water and cow-milk show relatively lower iodine levels in the Nowy Sacz voivodship. The estimated value of the iodine content in milk (5.5 micrograms/100 g of milk) was considered in the estimates of the chemical composition of the daily diet of the inhabitants of this region. The mean values of the daily energy as well as the protein and calcium consumption in all subpopulations grouped with respect to domicile, age and sex, fell within the recommended daily allowances for these groups. The iodine content, while widely scattered, concentrated around low values. The median values of the iodine content in children of age 3-10 years, age 10-16 years and in adults, were 66%, 48% and 25-40% of the recommended daily allowances, respectively. No particular differences in the food intakes were observed between inhabitants of Kraków and Nowy Sacz voivodships. Nor were significant differences found in the urine iodine excretion in groups of these regions. The low iodine content in the daily food intake may be an essential factor in the ethiology of the increasing number of thyroid goiter.  相似文献   
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The microbeam synchrotron X-ray fluorescence (MSXRF) technique is powerful tool for determining elemental composition and spatial distribution of elements within materials on the microscopic level. Therefore, application of this technique seems to be helpful for investigation of the role of trace elements in neurodegenerative processes. As a preliminary study the MSXRF technique was applied for elemental microanalysis in cryo-sections of substantia nigra tissue for cases of Parkinson's disease (PD) and the control. Two-dimensional maps of elemental distribution showed significant topographic and quantitative differences between the pathological and control tissues. Quite interesting is significant increased accumulation of Ca, Cu, Fe, Fe, and Zn that was observed in PD neuron perikaryal parts.  相似文献   
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Industrial waste substrata, rich in heavy metals, are poorly suited for plant growth. Efforts are made to establish an appropriate plant cover to reduce erosion and further contamination. Grasses are the usual solution, as they grow fast, thrive on poor substrata and have well-developed root systems. Some of them are also highly dependent on mycorrhizal symbiosis that supports their growth especially on poor and polluted soils. However, the commercially available grasses often meet a lack of well established mycorrhiza on the site and the introduced plant populations dramatically decrease with time, despite large financial input including covering the substratum with soil and intensive watering. The aim of this paper was to select proper plants together with mycorrhizal fungi that could accelerate the establishment of the vegetation and improve its diversity under these extreme conditions, minimizing the financial costs of the reclamation (no use of soil layering and watering). The experiments were carried out under field and laboratory conditions. The plant seeds used originated from dry calcareous grasslands. The seeds were germinated under field conditions or in pots filled with soil supplemented with substratum from the industrial wastes. The seedlings were inoculated with AM fungi and introduced on the field plots a few weeks after germination. The inoculum consisted of either crude inoculum harvested from the dry calcareous grasslands or strains originating from polluted areas. Plants colonized by mycorrhizal fungi established well in the experimental plots. The results suggest that inocula from dry calcareous grasslands are potentially useful in revegetation of industrial wastes. Although in several cases the photosynthetic activity of plants was lower than at the natural sites, almost all plants survived and formed seeds. In all experiments the plant vitality was estimated on the basis of chlorophyll a fluorescence and was useful to show differences between waste substrata, inocula and coexisting plant species. The interactions between mycorrhizal and non-mycorrhizal plants were studied under greenhouse conditions and at least no negative effect of this coexistence was found.  相似文献   
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Lentinula edodes (shiitake), an edible and medicinal mushroom, was chosen for this study with the aim of evaluating the possibility of release of bioelements into artificial digestive juices and analyzing the anti-inflammatory properties. The extracts were prepared from fruiting bodies and biomass enriched with copper (Cu), zinc (Zn), and selenium (Se). The content of bioelements was analyzed by total reflection X-ray fluorescence method. Relatively low content of elements was observed in the fruiting bodies: Cu–1.6, Zn–7.6, and Se–0.12 mg/100 g d.w. compared to mycelial cultures. The anti-inflammatory properties were evaluated in RAW 264.7 cells. Based on the levels of cyclooxygenase 2 protein, nuclear factor erythroid 2-related factor 2, and peroxisome proliferator-activated receptor γ determined using Western blot technique, it was found that the addition of bioelements enhanced the anti-inflammatory properties of mycelium. This indicates that L. edodes cultured on a suitable medium may be used as a potential component of anti-inflammatory products.

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Lead (Pb) is a known neurotoxic agent, however, mechanisms of its neurotoxicity are still an open question. The aim of the study was to assess the function of nerve endings and astroglia in regard to the relationships between GABA, glutamate and glutamine using the rodent model of Pb toxicity. Synaptosomal processes of radioactive neurotransmitter transport, both GABA and glutamate, were impaired. Moreover, the uptake of glutamine, involved in the neuronal recycling of the neurotransmitters GABA and glutamate, decreased. However, evidences of astroglial activation (enhanced uptake of glutamate and activation of glutamine synthetase) were observed, together with parallel existing weakness of glutamine transport. The results suggest that the disturbances in GABAergic and glutamateric neurotransmission may be partially the effect of impaired neuronal–astrocytic interaction, mainly in intercellular trafficking of glutamine.  相似文献   
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