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Nickel in the environment

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The importance of nickel (Ni) in the environment is an issue that is gaining broader recognition. While nickel is an element essential for plants, it is also a heavy metal. Nickel is a component of nine metalloenzymes, including urease, which participates in urea hydrolysis. It also helps some plants to protect themselves against pathogens and herbivorous insects. There are many sources of Ni in the environment, which can be a problem because at higher concentrations this element is toxic to plants and other living organisms. Therefore, standards have been defined for the Ni content in air, water, soil and plants. Its content is monitored in the air. More and more frequently, attention is paid to this element as an allergen in humans. In the world, attempts have been made to phytoextract nickel from contaminated soils using nickelphilous plants, the so-called hyperaccumulators, and even to recover the metal from these plants by so-called phytomining. On the other hand, nickel-containing fertilizers are marketed and used in cases of nickel deficiency in plants. In industry, this element is primarily used for the production of steel and alloys. The most recent application of nickel is related to graphene, which was invented 10 years ago. Although nickel contamination does not occur in Poland, we cannot rule out this risk in the future. Thus, it is important to monitor the fate of nickel in the environment.
The role of contact with nickel-containing coins has been controversial. The aim of our study was to compare the release of nickel from Euro (1 and 2) coins and from Polish coins (2 PLN and 5 PLN) at 4ºC and 32ºC in an immersion test using artificial sweat according to the EU reference method. Nickel extract was analyzed at 8 time points starting from 1 h up to 168 h. After 7 days of test duration at 32ºC, nickel ion concentration was 96.27±4.01 μg/cm2, 79.31±1.95 μg/cm2, 38.34±1.19 μg/cm2, and 32.17±2.36 μg/cm2 for 2 Euro, 1 Euro, 5 PLN, and 2 PLN, respectively. The amount of nickel ion released at 4ºC was reduced by about 70% and 40% for Euro and Polish coins, respectively. These values exceed the limit acceptable for prolonged contact with human skin as defined by the EU Nickel Directive, which indicates that nickel may be capable of eliciting allergic reactions in subjects handling nickel-containing coins daily.
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House dust is an important source of different toxic metabolites as well as allergens, including those of fungal origin, in the indoor environment. A bio-assay employing 1-day-old chick tracheas was used to characterize airway effects of 2-butanone and dimethylsulphoxide (Me2SO) extracts of 23 dust samples collected from water damaged (13) and control (10) Danish schools. Direct microscopical analysis of samples, followed by cultivation on dichloran 18% glycerol agar at 25oC for 10 days to establish their mycoflora, was performed. The in vitro ciliostatic potential of the chloroform-extractable endo- and exometabolites of 41 representative fungal isolates was determined. Nine dust extracts in 2-butanone (2 from damp rooms) or 10 (6) in Me2SO showed some ciliostatic activity in the 3-days' experiment. Fungal composition of dust from buildings with leakage was almost identical with that from undamaged houses, as well as the fungal colony counts from the damp schools and the control samples. Aspergillus spp. were prevalent in the samples - 31 or 40% of all fungi, followed by Penicillium spp. and Cladosporium cladosporioides. Alternaria spp., Chaetomium spp., Mucor spp., Mycelia sterilia, Paecilomyces variotii, Rhizopus sp., Ulocladium sp. and yeasts were each isolated in less than 8% of the fungal content. No Aspergillus flavus isolate (8 in total) was aflatoxigenic ,em>in vitro. Alternaria spp., Aspergillus spp., Botrytis cinerea, Penicillium spp., C. cladosporioides, Chaetomium spp. and Ulocladium sp.; in total, 88% of all fungi tested, produced ciliostatically active metabolites. These toxigenic strains were also present in 4 dust samples from controls and 5 dust samples from water damaged buildings. Extracts of these dust samples were also toxic in bioassay. There were bio-detectable concentrations (10-20 µg of extracts/ml of the organ culture medium) of toxic compounds in house dust. Contribution of fungal metabolites to its toxic effect should be studied further.
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Airborne pollen grains in Bursa, Turkey, 1999-2000

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In this study, pollen grains were sampled by using a Lanzoni trap (Lanzoni VPPS 2000) in atmosphere of Bursa in 1999 and 2000. During two years, a total of 13,991 pollen grains/m3 which belonged to 59 taxa and unidentified pollen grains were recorded. A total of 7,768 pollen grains were identified in 1999 and a total of 6,223 in 2000. From these taxa, 36 belong to arboreal and 23 taxa to non-arboreal plants. Total pollen grains consist of 78.61% arboreal, 20.37% non-arboreal plants and 1.03% unidentified pollen grains. In the region investigated, Pinus sp., Olea sp., Platanus sp., Gramineae, Cupressaceae/Taxaceae, Quercus sp., Acer sp., Morus sp. Xanthium sp., Castanea sp., Chenopodiaceae/Amaranthaceae, Corylus sp., Artemisia sp., Urtica sp. and Fraxinus sp. were responsible for the greatest amounts of pollen. During the study period the pollen concentration reached its highest level in April.
The presence of common epitopes among tropomyosins of invertebrates, including arthropods, e.g. edible ones, may help to explain the molecular basis of cross-reactivity between allergens. The work presented is the fi rst survey concerning global distribution of epitopes from Pen a 1.0102 in universal proteome. In the group of known tropomyosin epitopes, the fragment with the sequence ESKIVELEEEL was found in the sequence of channel catfish (Ictalurus punctatus) tropomyosin. To date, this is the fi rst result suggesting the presence of a complete sequential epitope interacting with IgE in vertebrate tropomyosin. Another fragment with the sequence VAALNRRIQL, a major part of the epitope, was found in 11 fi sh, 8 amphibians, 3 birds, 19 mammalians and 4 human tropomyosin sequences. Identical epitopes are common in sequences of invertebrate tropomyosins, including food and non-food allergens annotated in the Allergome database. The rare pentapeptide with the DEERM sequence occurs in proteins not sharing homology with tropomyosins. Pathogenic microorganisms are the most abundant category of organisms synthesizing such proteins.
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Birch pollen grains are one of the most important groups of atmospheric biological particles that induce allergic processes. The fluctuation pattern of birch pollen seasons in selected cities of Poland is presented. Measurements were performed by the volumetric method (Burkard and Lanzoni 2000 pollen samplers). The distributions of the data were not normal (Shapiro–Wilk test) and statistical error risk was estimated at a significance level of α = 0.05. Pollen season was defined as the period in which 95% of the annual total catch occurred. The linear trend for the selected features of the pollen season, skewness, kurtosis and coefficient of variation (V%) were also analyzed. During the 12–14 years of study, the beginnings of birch pollen seasons were observed 7–14 days earlier, the ends were noted 5–10 days earlier, and the days with maximum values occurred 7–14 days earlier compared to the long-term data. The left-skewed distribution of the pollen season starts in most sampling sites confirms the short-lasting occurrence of pollen in the air. The threat of birch pollen allergens was high during the pollen seasons. If vegetation is highly diverse, flowering and pollen release are extended in time, spread over different weeks and occur at different times of the day. Flowering time and pollen release are affected by insolation, convection currents, wind, and turbulence. Therefore, pollen seasons are characterized by great inter-annual variability.
Allergies and/or food intolerances are a growing problem of the modern world. Diffi culties associated with the correct diagnosis of food allergies result in the need to classify the factors causing allergies and allergens themselves. Therefore, internet databases and other bioinformatic tools play a special role in deepening knowledge of biologically-important compounds. Internet repositories, as a source of information on different chemical compounds, including those related to allergy and intolerance, are increasingly being used by scientists. Bioinformatic methods play a signifi cant role in biological and medical sciences, and their importance in food science is increasing. This study aimed at presenting selected databases and tools of bioinformatic analysis useful in research on food allergies, allergens (11 databases), epitopes (7 databases), and haptens (2 databases). It also presents examples of the application of computer methods in studies related to allergies.
Glycation (non-enzymatic glycosylation) is a spontaneous reaction that occurs during food processing, storage and preparation of food, which can have a significant influence on physiochemical and biological properties of food proteins. Glycation has been used mostly for improvement of functional properties of proteins although there is increasing concern of possible changes in biologic properties of glycation products. The influence of dry-heat glycation with glucose on immunoreactive properties of wheat salt-soluble proteins has been studied. It has been shown that glycation caused differences in electrophoretic patterns (both 1D and 2D), as well as in Western-immunoblotting with rabbit IgG and human IgE. A significant increase in immunoreactivity has been observed, as well as a decrease in free amino group. Thermostable, immunoreactive and susceptible for glycation protein band with molecular weight of approximately 13 kDa (by SDS-PAGE) has been selected for the N-terminal sequence analysis and determined to be an alpha-amylase inhibitor. Dry heat glycation is a very potent but nondestructive method of protein glycation, that leads to high degree of substitution and changes in both physicochemical and biological (immunological) properties of food proteins.
Introduction. Occupational exposure to bio-aerosols has been linked to various health effects. This review presents an overview of bio-aerosol exposure levels in veterinary practices, and investigates the possibility of health effects associated with bio-aerosol exposure. Methods. A systematic literature search was carried out in PubMed. Publications were included if they provided information on bio-aerosol exposure and related health effects through veterinary practice and other professions with similar exposures, occupationally exposed to animals. Results. Few studies in veterinary settings showed that substantial bio-aerosol exposure levels (e.g. endotoxin and β(1→3)-glucan) were likely occur when handling farm animals and horses. Exposure levels are comparable to those levels observed in farming which have been associated with respiratory health effects. Animal specific allergen exposures have hardly been studied, but showed to be measurable in companion animal clinics and dairy barns. The findings of the few studies available among veterinary populations, particularly those working with farm animals and horses, are indicative of an elevated risk for developing respiratory symptoms. Studies among pig farmers, exposed to similar environments as veterinarians, strongly confirm that veterinary populations are at an increased risk of developing respiratory diseases in relation to bio-aerosol exposure, in particular endotoxin. Exposure to animal allergens during veterinary practice may cause allergic inflammation, characterized by IgE-mediated reactions to animal allergens. Nonetheless, the occurrence of sensitization or allergy against animal allergens is poorly described, apart from laboratory animal allergy, especially known from exposure to rats and mice. Conclusion. Veterinary populations are likely exposed to elevated levels of bio-aerosols such as endotoxins, β(1→3)-glucans, and some specific animal allergens. Exposures to these agents in animal farmers are associated with allergic and non-allergic respiratory effects, proposing similar health effects in veterinary populations.
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Nasal provocative test (NPT) can be defined as a method for recreating upper respiratory tract response to natural allergens or irritants. It can be used in solving nasal patophisiology problems: establishing whether and how the patient's nose is sensitive to antigens or irritants; quantitative evaluation of sensitivity; establishing factors influencing sensitivity. This method is employed to confirm clinical diagnosis in cases where difficulties arise in interpretation of diagnostic tests. The study based on nasal provocative tests establish an allergy to pollen in cases of pollinosis, and select appropriate components for the desensitising vaccine. Sample group included 53 patients, 29 were females and 24 were males, aged 15-42 years, selected from 1,021 patients diagnosed between 1999-2002 in the Allergology Department of the ENT Department of the MMI. The sample patients were diagnosed based on additional tests with allergic inflammation of the nasal mucosa caused by allergy to pollen of such plants as birch, grass, rye, mugwort and plantain. Research methods included: subjective physical examination, prick tests, total and specific IgE levels in serum, nasal provocative tests and rhinomanometric examination. Allergen solution was administered onto the mucosa with a calibrated atomiser. NPT solutions containing pollen of birch, grass, rye, mugwort and plantain were used. Provocative test was considered positive if, following allergen provocation, rhinomanometric examination revealed an increase in respiratory resistance by at least 40% in comparison with the control test. On the basis of the study, 2 conclusions were drawn: 1) Nasal provocative test is an essential element in diagnostics of allergic nasal obstruction. 2) Rhinomanometry, as an objective method of examining nasal patency, is crucial for evaluating the nasal provocative test.
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Pollen and spore forecasting has become an important aim in aerobiology. The main goal is to provide accurate information on biological particles in the air to sensitive users in order to help them optimize their treatment process. Many statistical methods of data analysis are based on the assumptions of linearity and normality that often cannot be fulfilled. The advanced statistical methods can be applied to the problems that cannot be solved in any other effective way, and are suited to predicting the concentration of airborne pollen or spores in relation to weather conditions. The purpose of the study was to review some advanced statistical methods that can be used in aerobiological studies.
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