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 Cadmium is a toxic and carcinogenic heavy metal that nowadays constitutes a serious environmental health problem. The aim of this study is to review the effects of cadmium on selected inflammatory mediators and markers, such as NF-κB and AP-1 transcription factors, IL-6, TNF-α, IL-1β cytokines, IL-8 or MIP-2 chemokine, MPO, iNOS, MMPs and COX-2 enzymes, PGE2 (product of COX-2 enzyme), ICAM-1, VCAM-1 and PECAM-1 adhesion molecules, and CRP. The research strategy identified articles; available in , published between 1998 and 2012; we included both in vivo and in vitro studies carried out on humans and rodents. Most of the reviewed research findings suggest that cadmium in micromolar concentrations (especially in the 1-10 μM range) causes up-regulation of the mediators and markers of inflammation, and appears to have pro-inflammatory properties. However, it is worth mentioning that a contradictory or even opposite hypothesis exists, which suggests cadmium to be an anti-inflammatory factor. Further research including detailed histological analyses should solve this discrepancy. Nevertheless, it appears that the main reason for these contradictory findings is the experimental setup: different biological systems analyzed and different doses of cadmium applied.
Vanadium belongs to the group of transition metals and is present in the air and soil contaminants in large urban agglomerations due to combustion of fossil fuels. It forms numerous inorganic compounds (vanadyl sulfate, sodium metavanadate, sodium orthovanadate, vanadium pentoxide) as well as complexes with organic compounds (BMOV, BEOV, METVAN). Depending on the research model, vanadium compounds exhibit antitumor or carcinogenic properties. Vanadium compounds generate ROS as a result of Fenton's reaction or of the reaction with atmospheric oxygen. They inactivate the Cdc25B2 phosphatase and lead to degradation of Cdc25C, which induces G2/M phase arrest. In cells, vanadium compounds activate numerous signaling pathways and transcription factors, including PI3K-PKB/Akt-mTOR, NF-κB, MEK1/2-ERK, that cause cell survival or increased expression and release of VEGF. Vanadium compounds inhibit p53-dependent apoptosis and promote entry into the S phase of cells containing functional p53 protein. In addition, vanadium compounds, in particular organic derivatives, have insulin-mimetic and antidiabetic properties. Vanadium compounds lower blood glucose levels in animals and in clinical trials. They also inhibit the activity of protein tyrosine phosphatase 1B. By activating the PI3K-PKB/Akt pathway, vanadium compaunds increase the cellular uptake of glucose by the GLUT4 transporter. The PKB/Akt pathway is also used to inactivate glycogen synthase kinase-3. The impact of vanadium compounds on inflammatory reactions has not been fully studied. Vanadium pentoxide causes expression of COX-2 and the release of proinflammatory cytokines in a human lung fibroblast model. Other vanadium compounds activate NF-κB in macrophages by activating IKKβ.
Zaburzenia w składzie mineralnym mogą bezpośrednio decydować o zdrowotnym stanie zębów. Celem badań było zbadanie zależności ilościowych między zawartością magnezu i zawartością wapnia w zawiązkach zębowych i zębach. Materiał do badań stanowiły zawiązki zębów trzonowych płodów oraz zęby mleczne i stałe pochodzące od pacjentów leczonych w Przychodniach Rejonowych Szczecina. Zawartość magnezu i wapnia w przygotowanych próbkach oznaczano metodą absorpcyjnej spektrometrii atomowej. Opracowanie statystyczne danych wykonano z użyciem programu statystycznego Statistica PL v 5.0. Na podstawie otrzymanych wyników stwierdzono, że zawartość magnezu i wapnia nie koreluje z wiekiem w zębach mlecznych i stałych, natomiast koreluje dodatnio w zawiązkach zębowych. Przeprowadzone badania wskazują na zmiany ilościowe zachodzące w części mineralnej twardych tkanek zęba, zarówno w pre-, jak i posterupcyjnej fazie mineralizacji. W zębach mlecznych wyraźnie uwidaczniają się różnice ilościowe między magnezem a wapniem. Ocena zawartości pierwiastków w zawiązkach zębowych, zębach mlecznych i stałych daje pełniejszy obraz przemian chemicznych w ciągu życia osobniczego.
Background. Although Poland belongs to the economically developed countries, social transformations affect people’s incomes and, consequently, their diets, what in many cases caused development of diet-related diseases. Results of epidemiological studies among students show symptoms of certain civilization diseases. Objective. The aim of this study was to compare the intake of nutrients by Polish students in our study with the nutrients intake by students from other university centres abroad and the determination of the direct impact on health parameters of educated people. Material and Methods. The study involved 329 Polish students. The dietary information was collected by interview on food intake during the last 24 hours. The index of BMI and WHR were calculated using anthropometric method. 27 nutrients, dietary fibre and daily total cholesterol intake with the computer program „Dietetyk 2” (National Food and Nutrition Institute, Warsaw, Poland). Results. Both women and men consume inadequate amounts of milk and dairy products, fruits, vegetables, vitamin C and iron. The average daily intake of vitamin C and iron was below the standard of nutrition. Diets in men was characterized by excessive content of meat and in women sucrose. 35% of the students surveyed were overweight or obese. There was a lot of irregularities in the diet of both women and men, but men’s diet was more balanced in terms of nutrient content than the diet of women. Conclusions. The delivery of thiamine, riboflavin, calcium, and vitamin C is less in Polish students than in other populations compared. Nutritional mistakes and dietary habits during studies can influence the development of disease in young educated people.
Oznaczano zawartość pierwiastków w kościach ogonowych owiec rasy laine-merynos pochodzących z czterech owczarni położonych na obszarze województwa zachodniopomorskiego. Materiałem do analizy były kręgi ogonowe owiec, które amputowano żywym owcom. Oznaczenia wykonano za pomocą metody potencjometrycznej dla oznaczenia fluorków, kolorymetrycznej dla oznaczania fosforanów oraz absorpcyjnej spektrofotometrii atomowej dla pozostałych pierwiastków: Ca, Mg, Fe i Zn. Obliczenia statystyczne, a w szczególności analizę parametryczną, wykonano za pomocą programu komputerowego Statistica i Statistica Neural Network.
Our study assesses environmental lead and fluoride pollution in West Pomeranian forests in Poland, on the basis of chemical analysis of antlers and skull bones of roe deer (Capreolus capreolus L.) from the surroundings of Szczecin and Drawsko Pomorskie, Poland. Lead was measured by atomic absorption spectrometry, and fluorides by using an ion-selective electrode. Our study indicates greater lead contamination in the forests near Drawsko Pomorskie than in the forests near Szczecin. The cause may be their long-term exploitation as a military area. The roe deer population near Szczecin is exposed to increased fluoride pollution, but the concentration of fluoride in hard tissues of roe deer has diminished considerably in comparison with data acollected 10 years prior to our study.
Lead (Pb2+) is a widespread pollutant and potent central neurotoxin. We have studied its effect on energetic metabolism of cerebellar granule cells (CGC) in pre- and postnatally intoxicated rats. Pregnant Wistar rats received 0.1% lead acetate in water. CGC were prepared from 8-day-old born rats according to a standard procedure. Pb2+concentration was measured in blood and in cerebellum homogenates by AAS. Intracellular Pb2+ concentrations in CGC was studied by fl uorescent microscopy, in neurons loaded with the Ca2+-sensitive indicator Oregon Green. Intracellular Pb2+ was evaluated from the fl uorescence intensity and estimate in μM range. Pb-induced decrease in Adenylate Energy Charge (by 10%) and ATP concentration (by 35%) in cerebellum homogenates (HPLC method) was observed at Pb concentrations in whole blood (7.05 ± 2.05 μg/dL).The function of mitochondria of neurons of Pb-treated and control rats were evaluated using: Mitotracker Green FM and JC-1. We observed active mitochondria stained green with Mitotracker in cytoplasm of CGC from control and Pb-treated rats. Incubation of cultured CGC from rats of control groups with the mitochondrial probe JC-1 produced red-orange fl uorescence showing mitochondria with high membrane potential ΔΨ. The green fl uorescence dependent on mitochondria with low ΔΨ was visible in cytoplasm of cells in Pb-treated rats. Pre- and postnatal low-level exposure to lead caused disruption of mitochondria energetic status in neurons.
The permissible threshold level of lead in blood (Pb-B) is currently established at 5 mg dL-1, but evidence suggests that it is impossible to determine the safety threshold for lead (Pb) and any exposure, especially in children, must be considered as potentially harmful. Methods used to reduce the concentration of Pb in blood (e.g. EDTA, penicillamine) are not always effective and are associated with serious side effects. One of the proposed dietary supplements in the case of exposure to Pb and low blood Pb concentrations is zinc (Zn), but the published literature on its effectiveness is limited. Therefore, the aim of this study was to clarify whether Zn supplementation may help reduce the concentration of Pb in the blood and tissues of rats, at the Pb-B level previously recognized as safe. Tests were performed on 6-8 week old male Wistar rats. Rats were divided into control and experimental groups: Group C – rats receiving drinking water ad libitum for 4 weeks; Group Pb – rats receiving Pb acetate 0.1% (PbAc) in drinking water ad libitum for 4 weeks; Group Zn – rats receiving ZnCO3 300 mg kg-1 diet for 4 weeks; Group Pb+Zn – rats receiving PbAc in drinking water ad libitum plus 300 mg ZnCO3 kg-1 diet for 4 weeks. The applied dose of 300 mg of ZnCO3 kg-1 diet results in a high but non-toxic Zn level. The concentrations of Pb and Zn in blood, plasma, liver and bone were determined by emission spectrometry in inductively coupled argon plasma (ICP OES). Incidental exposure of adult rats to Pb at doses resulting in the level of Pb in blood below the previously recognized as safe one caused: (i) increased Pb concentration in the bones and plasma and its reduction in the whole blood and liver (ii) simultaneous supplementation of rats exposed to Pb with a high but non-toxic dose of zinc did not result in the reduction of the Pb concentration in the blood and tissues of rats, nor did it induce any changes in the distribution of Pb in the examined tissues (iii) supplementation of diets with a high but non-toxic dose of Zn is not an effective method of reducing the concentration of Pb in blood at Pb-B previously recognized as safe. However, the therapy consisting of zinc supplementation to support the action of chelators could be crucial for the elimination of Pb from the body.
Annual shedding of antlers by males is a characteristic feature of most deer species. Regrowth is very fast, reaching 2 cm/day for some species and making them an interesting model for studying tissue regeneration processes. The aim of this study was to compare the contents of calcium, magnesium, and phosphorus in antlers and cranial bones of European red deer from Western Pomerania, Poland. We obtained 30 antlers from three forestry districts that differed in the extent of environmental pollution with fluorine compounds, SO₂, NOx, CO, and CO₂ (Trzebież, Rokita and Gryfino). Deer were assigned to two age groups: from 2 to 4 years, and from 6 to 8 years. Powdered samples of cranial bones and antler base obtained with a dental drill were dissolved in nitric acid. Calcium and magnesium contents were measured by atomic absorption spectroscopy, while phosphorus was determined colorimetrically. The content of calcium was higher in antlers - (mean 133.96 mg/g) hardly surprising given the higher calcified cartilage and immature bone content in antler as opposed to cranial bone (mean 123.79 mg/g). Phosphorus content was slightly higher in bones than in antlers (84.62 mg/g and 83.58 mg/g, respectively), which suggests that Ca:P ratios are different in the mineral phase or that there is more P in bone compared to the antler matrix. No difference in magnesium content was noted (5.23 to 5.46 mg/g). Statistical analysis revealed significant differences depending on age of the animal and level of industrial pollution in the animal's habitat.
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