| 1. |
- Bedada, G. B., et al.
(författare)
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Urban background particulate matter and allergic sensitization in adults of ECRHS II
- 2007
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Ingår i: Int J Hyg Environ Health. - : Elsevier BV. - 1438-4639. ; 210:6, s. 691-700
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Epidemiological studies have shown weak or inconsistent associations between ambient air pollutants and allergic sensitization. The aim of this study was to evaluate whether regional urban air pollution may partly explain the large variation in the prevalence of allergic sensitization across cities of the European Community Respiratory Health Survey (ECRHS) II. METHODS: ECRHS is a cross-sectional survey initiated in 29 countries across Europe in the 1990s (ECRHS I) with a follow-up conducted 10 years later (ECRHS II). Subject characteristics were measured by questionnaires and blood tests conducted for the measurement of specific immunoglobulin E. Fine particle mass (PM(2.5), <2.5mum) and sulphur on PM(2.5) were measured in 21 centres and annual averages of urban regional background air pollution were calculated. Results were scaled by an interquartile range increase in ambient PM(2.5) (6.03mug/m(3)) and sulphur (1336ng/m(3)). Generalized estimating equations were applied to compute population average effect estimates with adjustment for age, gender, smoking habit, education and number of siblings. RESULTS: A notable variation in pollution level and prevalence of allergic sensitization was observed. Moreover, exposure to urban regional background air pollution was not associated with allergic sensitization; adjusted odds ratios and 95% confidence interval were 1.02 (0.95-1.09) for PM(2.5) and 1.08 (0.86-1.31) for sulphur. These statistically non-significant associations were sensitive to model specification. CONCLUSIONS: The study suggests that regional air pollution measured at fixed sites is not associated with allergic sensitization among adults in ECRHS II.
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| 2. |
- Castro-Giner, F., et al.
(författare)
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Joint effect of obesity and TNFA variability on asthma : two international cohort studies
- 2009
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Ingår i: European Respiratory Journal. - : European Respiratory Society (ERS). - 0903-1936 .- 1399-3003. ; 33:5, s. 1003-1009
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Tidskriftsartikel (refereegranskat)abstract
- Obesity is a risk factor for asthma. Adipose tissue expresses pro-inflammatory molecules including tumour necrosis factor (TNF), and levels of TNF are also related to polymorphisms in the TNF-alpha (TNFA) gene. The current authors examined the joint effect of obesity and TNFA variability on asthma in adults by combining two population-based studies. The European Community Respiratory Health Survey and the Swiss Cohort Study on Air Pollution and Lung and Heart Disease in Adults used comparable protocols, questionnaires and measures of lung function and atopy. DNA samples from 9,167 participants were genotyped for TNFA -308 and lymphotoxin-alpha (LTA) +252 gene variants. Obesity and TNFA were associated with asthma when mutually adjusting for their independent effects (odds ratio (OR) for obesity 2.4, 95% confidence interval (CI) 1.7-3.2; OR for TNFA -308 polymorphism 1.3, 95% CI 1.1-1.6). The association of obesity with asthma was stronger for subjects carrying the G/A and A/A TNFA -308 genotypes compared with the more common G/G genotype, particularly among nonatopics (OR for G/A and A/A genotypes 6.1, 95% CI 2.5-14.4; OR for G/G genotype 1.7, 95% CI 0.8-3.3). The present findings provide, for the first time, evidence for a complex pattern of interaction between obesity, a pro-inflammatory genetic factor and asthma.
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| 3. |
- Cerveri, I, et al.
(författare)
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What defines airflow obstruction in asthma?
- 2009
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Ingår i: European Respiratory Journal. - : European Respiratory Society (ERS). - 0903-1936 .- 1399-3003. ; 34:3, s. 568-573
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Tidskriftsartikel (refereegranskat)abstract
- Asthma guidelines from the Global Initiative for Asthma (GINA) and from the National Heart, Lung, and Blood Institute provide conflicting definitions of airflow obstruction, suggesting a fixed forced expiratory volume in 1 s (FEV(1))/forced vital capacity (FVC) cut-off point and the lower limit of normality (LLN), respectively. The LLN was recommended by the recent American Thoracic Society/European Respiratory Society guidelines on lung function testing. The problem in using fixed cut-off points is that they are set regardless of age and sex in an attempt to simplify diagnosis at the expense of misclassification. The sensitivity and specificity of fixed FEV(1)/FVC ratios of 0.70, 0.75 and 0.80 versus the LLN were evaluated in 815 subjects (aged 20-44 yrs) with a diagnosis of asthma within the framework of the European Community Respiratory Health Survey. In males, the 0.70 ratio showed 76.5% sensitivity and 100.0% specificity, the 0.75 ratio 100.0% sensitivity and 92.4% specificity, and the 0.80 ratio 100.0% sensitivity but 58.1% specificity. In females, the 0.70 ratio showed 57.3% sensitivity and 100.0% specificity, the 0.75 ratio 91.5% sensitivity and 95.9% specificity, and the 0.80 ratio 100.0% sensitivity but 72.9% specificity. The fixed cut-off points cause a lot of misidentification of airflow obstruction in young adults, with overestimation with the 0.80 ratio and underestimation with the 0.70 ratio. In conclusion, the GINA guidelines should change their criteria for defining airflow obstruction.
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| 4. |
- Echtermeyer, Tim J., et al.
(författare)
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Nonvolatile switching in graphene field-effect devices
- 2008
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Ingår i: IEEE Electron Device Letters. - 0741-3106 .- 1558-0563. ; 29:8, s. 952-954
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Tidskriftsartikel (refereegranskat)abstract
- The absence of a band gap in graphene restricts its straightforward application as a channel material in field-effect transistors. In this letter, we report on a new approach to engineer a band gap in graphene field-effect devices (FEDs) by controlled structural modification of the graphene channel itself. The conductance in the FEDs is switched between a conductive "ON-state" and an insulating "OFF-state" with more than six orders of magnitude difference in conductance. Above a critical value of an electric field applied to the FED gate under certain environmental conditions, a chemical modification takes place to form insulating graphene derivatives. The effect can be reversed by electrical fields of opposite polarity or short current pulses to recover the initial state. These reversible switches could potentially be applied to nonvolatile memories and novel neuromorphic processing concepts.
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| 5. |
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| 6. |
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| 7. |
- Jacquemin, B., et al.
(författare)
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Annoyance due to air pollution in Europe
- 2007
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Ingår i: Int J Epidemiol. - : Oxford University Press (OUP). - 0300-5771 .- 1464-3685. ; 36:4, s. 809-20
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Annoyance due to air pollution is a subjective score of air quality, which has been incorporated into the National Environmental monitoring of some countries. The objectives of this study are to describe the variations in annoyance due to air pollution in Europe and its individual and environmental determinants. METHODS: This study took place in the context of the European Community Respiratory Health Survey II (ECRHS II) that was conducted during 1999-2001. It included 25 centres in 12 countries and 7867 randomly selected adults from the general population. Annoyance due to air pollution was self-reported on an 11-point scale. Annual mean mass concentration of fine particles (PM(2.5)) and its sulphur (S) content were measured in 21 centres as a surrogate of urban air pollution. RESULTS: Forty-three per cent of participants reported moderate annoyance (1-5 on the scale) and 14% high annoyance (>/=6) with large differences across centres (2-40% of high annoyance). Participants in the Northern European countries reported less annoyance. Female gender, nocturnal dyspnoea, phlegm and rhinitis, self-reported car and heavy vehicle traffic in front of the home, high education, non-smoking and exposure to environmental tobacco smoke were associated with higher annoyance levels. At the centre level, adjusted means of annoyance scores were moderately associated with sulphur urban levels (slope 1.43 mug m(-3), standard error 0.40, r = 0.61). CONCLUSIONS: Annoyance due to air pollution is frequent in Europe. Individuals' annoyance may be a useful measure of perceived ambient quality and could be considered a complementary tool for health surveillance.
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| 8. |
- Jacquemin, B, et al.
(författare)
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Association between annoyance and individuals' values of nitrogen dioxide in a European setting.
- 2008
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Ingår i: Journal of epidemiology and community health. - 1470-2738. ; 62:5, s. e12-
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Annoyance caused by air pollution has been proposed as an indicator of exposure to air pollution. The aim of this study was to assess the geographical homogeneity of the relationship between annoyance and modelled home-based nitrogen dioxide (NO2) measurements. METHODS: The European Community Respiratory Health Survey II was conducted in 2000-1, in 25 European centres in 12 countries. This analysis included 4753 subjects (from 37 in Tartu, Estonia, to 532 in Antwerp, Belgium) who answered the annoyance question and with available outdoor residential NO2 (4399 modelled and 354 measured) including 20 cities from 10 countries. Annoyance as a result of air pollution was self-reported on an 11-point scale (0, no disturbance at all; 10, intolerable disturbance). Demographic and socioeconomic factors, smoking status and the presence of respiratory symptoms or disease were measured through a standard questionnaire. Negative binomial regression was used. RESULTS: The median NO2 concentration was 27 microg.m(-3) (from 10 in Umeå, Sweden, to 57 in Barcelona, Spain). The mean of annoyance was 2.5 (from 0.7 in Reykjavik, Iceland, to 4.4 in Huelva, Spain). NO2 was associated with annoyance (ratio of the mean score 1.26 per 10 microg.m(-3), 95% CI 1.19 to 1.34). The association between NO2 and annoyance was heterogeneous among cities (p for heterogeneity <0.001). CONCLUSIONS: Annoyance is associated with home outdoor air pollution but with a different strength by city. This indicates that annoyance is not a valid surrogate for air pollution exposure. Nevertheless, it may be a useful measure of perceived ambient air quality and could be considered a complementary tool for health surveillance.
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| 9. |
- Jacquemin, B, et al.
(författare)
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Association between modelled traffic related air pollution (NO2) and asthma score in ECHRS.
- 2009
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Ingår i: European Respiratory Journal. - : The European Respiratory Society. - 0903-1936 .- 1399-3003. ; 34:4, s. 834-842
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this analysis is to study the association between air pollution and asthma among adults. For this goal, a previously developed "asthma score" was used.Persons aged 25-44 years were randomly selected (1991-1993) and followed up (2000-2002) within the European Community Respiratory Health Survey (ECRHS-I and II). The asthma score was defined from 0 to 5, based on positive answers to symptoms reported for the last 12 months: wheeze/breathlessness, chest tightness, dyspnoea at rest, dyspnoea after exercise, and woken by dyspnoea. Participants' home addresses were linked to outdoor modelled NO2 estimates for 2001. Negative binomial regression was used to model the asthma score.The score from ECRHS-II was positively associated with NO2 (Ratio of the Mean asthma Score (RMS) 1.23, 95% Confidence Intervals (CI): 1.09-1.38 for an increase of 10 microg.m(-3)). After excluding participants with asthma and symptoms at baseline, the association remained (RMS 1.25, 95%CI: 1.05-1.51) and was particularly high among those reporting a high score in ECRHS-II. The latter probably reflects incident cases of asthma.Our results suggest that traffic-related pollution causes asthma symptoms and possibly asthma incidence in adults. The asthma score offers an alternative to investigate the course and aetiology of asthma in adults.
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