Search Results - (Author, Cooperation:M. Vasar)

2015-09-01

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Animals ; Biodiversity ; DNA, Fungal/analysis ; *Ecosystem ; Environment ; Humans ; *Mycorrhizae/genetics/isolation & purification/physiology ; Phylogeny ; Phylogeography ; Plant Roots/*microbiology ; *Symbiosis ; Water ; Wind

1398-9995

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The prevalence of allergic disease is low in Eastern Europe for reasons that are poorly understood. Our study aimed to investigate the levels of exposure to indoor allergens and living conditions among Estonian infants in relation to sensitization. Dust samples were collected during four winter months in 1993/94 from the homes of 197 infants participating in a prospective study of sensitization. Information about living conditions was collected through home visit and interviewing the mothers when the children were 6 weeks old. Three dust samples were collected from each home: i.e., from the infant's mattress, bedroom floor, and living-room carpet. The levels of allergens were determined by ELISA with monoclonal antibodies. The highest allergen level in a home was regarded as the peak value. The peak geometric mean values (±SD) of Der p 1 and Der f 1 were 0.3 (0.07–1.4) μg/g dust, of Can 1, 0.86 (0.23–3.12) μg/g dust, and of Fel d 1, 0.1 (0.01–0.9) μg/g dust. In 12 homes (9%), the peak value of house-dust mite (HDM) allergens exceeded 2 μg/g dust, with Der p 1 as the dominating allergen. Multivariate analyses indicated that high levels of HDM allergens were more common in apartments that were on the ground floor or first floor, that were heated with stoves, and/or that had a dampness problem. The mean allergen levels at home were similar in children sensitized to HDM (n = 17. 0.29 v.s 0.3 μg/g dust), dog (n=5, 0.55 vs 1.06 μg/g dust, and cat (n= 18, 0.21 vs 0.09 μg/g dust) and in children who were not sensitized to these allergens. Most of the sensitized children were exposed to relatively low allergen levels at home; i.e., below 1 μg/g dust. This level was exceeded in the homes of 4/17 mite-, 5/18 cat-, and 0/5 dog-sensitized children. The similar levels of the major indoor allergens in Estonia and in Scandinavia indicate that the large differences in atopy prevalence among children and young adults in the two regions are not due to differences in allergen exposure. No allergen threshold level for sensitization was identified.

Electronic Resource

1399-3038

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

There is a lack of established criteria to identify asthma and bronchial hyerreactivity (BHR) in epidemiological studies, although both conditions appear to bear some relationship to atopy, at least in children. Recent studies indicate a low prevalence of atopy in former Socialist countries in Europe, yet the prevalence of BHR has been reported to be high. We have analysed the relationship between the outcome of various lung function tests, atopy and clinical symptoms of bronchial asthma in an epidemiological survey of Estonian 10-12 year old schoolchildren. Metacholine provocation test (four steps with the cumulative doses 100, 300, 700 and 1100uμg), exercise challenge test and PEF-variability over two weeks were done in 806 children in Tallinn (coastal, industrialised city) and 774 children in Tartu (inland, uniersity town). A positive response to the metacholine challenge test was recorded in 19% in Tallinn and in 32% in Tartu (p 〈 0.001). A similar tendency was observed for a more than 15% decrease of FEV1 in the exercise challenge test, i. e. 6% in Tallinn and 18% in Tartu. There was only a weak relationship between BHR, as defined by either a positive metacholine challenge and/or exercise test, diagnosed asthma and reported wheezing. Thus, 47% of the wheezing children and 30% of the children with asthma had negative test results. Only 17% of the children with a positive metacholine challenge were atopic, as defined by at least one positive skin prick test. In conclusion, none of the methods employed to assess bronchial hyperre-sponsiveness were very useful for the identification of wheezing and asthmatic children in this epidemiological study. In contrast to the results of studies in Western Europe, most children with bronchial hyperreactivity in Estonia are not atopic.

Electronic Resource

1365-2222

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background Epidemiological studies have demonstrated a low prevalence of allergic diseases and atopic sensitization among schoolchildren and young adults in the formerly socialist countries of Central and Eastern Europe as compared to Western Europe.Objective The aim of our study was to prospectively investigate IgE responses to food and inhalant allergens and the development of allergy during early childhood in a population with a low prevalence of atopic disorders.Methods In a population-based prospective study, 273 children were followed from birth through the first 5 years of life, recording manifestations of allergy by questionnaires and clinical examinations at 0.5, 1, 2 and 5 years (n = 213). Skin prick tests (SPT) were performed using natural foods (cow's milk, egg white) and commercial extracts of inhaled allergens (cat, dog, D. pteronyssinus, birch, timothy). In addition, serum IgE levels and circulating IgE antibodies against the seven allergens were determined.Results The prevalence of allergic diseases at 5 years of life was 19%. Atopic dermatitis was the most common allergic disease at all ages. The point prevalence of positive skin prick tests was 7% at 0.5, 1 and 2 years of age, and 3% at 5 years. Circulating IgE antibodies against food allergens were common at all ages, i.e. 13, 23, 36 and 36%, respectively, at 0.5, 1, 2 and 5 years. The prevalence of circulating IgE antibodies to inhalant allergens increased from 1.5% at 0.5 years to 11% at 1, 19% at 2 and 47% at 5 years. The antibody levels were generally low, however. The value of positive SPT and the presence of IgE antibodies in the diagnosis of clinical allergy were low.Conclusion The results of this prospective study carried out in a previously socialist country with a low allergy prevalence among schoolchildren and young adults indicate that transient sensitization in early childhood is followed by a down-regulation of skin reactivity.

Electronic Resource