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- Högman, Marieann, et al.
(author)
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Extended NO analysis in a healthy subgroup of a random sample from a Swedish population
- 2009
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In: Clinical Physiology and Functional Imaging. - 1475-0961 .- 1475-097X. ; 29:1, s. 18-23
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Journal article (peer-reviewed)abstract
- INTRODUCTION: There is an interest in modelling exhaled nitric oxide (NO). Studies have shown that flow-independent NO parameters i.e. NO of the alveolar region (C(A)NO), airway wall (C(aw)NO), diffusing capacity (D(aw)NO) and flux (J(aw)NO), are altered in several disease states such as asthma, cystic fibrosis, alveolitis and chronic obsmuctive pulmonary disease (COPD). However, values from a healthy population are missing. OBJECTIVES: To calculate NO parameters in a healthy population by collecting NO values at different exhalation flow rates. METHODS: A random sample from the ECRHS II study was investigated. Among the 281 subjects that had performed a bronchial hyperreactivity (BHR)-test, FEV(1.0), IgE and NO-analyses 89 were found to be healthy. RESULTS: There were no differences in F(E)NO(0.05) or NO parameters between men and women. There were weak correlations between height and both F(E)NO(0.05) (r = 0.23, P = 0.03) and C(aw)NO (r = 0.22, P = 0.04). There was also a correlation between age and C(A)NO (r = 0.28, P = 0.007). When controlled for gender, this correlation was more powerful in women (r = 0.51, P = 0.001) but did not remain for male subjects. CONCLUSION: Extended NO analysis is a simple non-invasive tool that gives by far more information than F(E)NO(0.05). Based on our results, we suggest that the values for healthy subjects should be considered to fall between the following ranges: F(E)NO(0.05), 10-30 ppb; C(aw)NO, 50-250 ppb; D(aw)NO, 5-15 ml s(-1); J(aw)NO, 0.8-1.6 nl s(-1); and C(A)NO, 0-4 ppb. Values outside these intervals indicate the need for further investigation to exclude a state of disease.
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| 2. |
- Högman, Marieann, et al.
(author)
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Extended NO analysis in asthma
- 2007
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In: Journal of Breath Research. - : IOP Publishing. - 1752-7155 .- 1752-7163. ; 1:2, s. 024001-
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Research review (peer-reviewed)abstract
- The discovery of the flow dependence of exhaled NO made it possible to model NO production in the lung. The linear model provides information about the maximal flux of NO from the airways and the alveolar concentrations of NO. Nonlinear models give additional flow-independent parameters such as airway diffusing capacity and airway wall concentrations of NO. When these models are applied to patients with asthma, a clear-cut increase in NO flux is found, and this is caused by an increase in both airway diffusing capacity and airway wall concentrations of NO. There is no difference in alveolar concentrations of NO compared to healthy subjects, except in severe asthma where an increase has been found. Inhaled corticosteroids are able to reduce the airway wall concentrations but not diffusing capacity or alveolar concentrations. Oral prednisone affects the alveolar concentration, suggesting that in severe asthma there is a systemic component. Steroids distributed by any route do not affect the airway diffusing capacity. Therefore, the airway diffusing capacity should be in focus in testing new drugs or in combination treatment for asthma. Exhaled NO analysis is a promising tool in characterizing asthma in both adults and children. However, there is a strong need to agree on the models and to standardize the flow rates to be used for the modelling in order to perform a systematic and robust analysis of NO production in the lung.
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| 3. |
- Malinovschi, Andrei, et al.
(author)
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IgE sensitisation in relation to flow-independent nitric oxide exchange parameters
- 2006
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In: Respiratory Research. - : Springer Science and Business Media LLC. - 1465-9921 .- 1465-993X. ; 7, s. 92-
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Journal article (peer-reviewed)abstract
- Background: A positive association between IgE sensitisation and exhaled NO levels has been found in several studies, but there are no reports on the compartment of the lung that is responsible for the increase in exhaled NO levels seen in IgE-sensitised subjects.Methods: The present study comprised 288 adult subjects from the European Community Respiratory Health Survey II who were investigated in terms of lung function, IgE sensitisation ( sum of specific IgE), smoking history and presence of rhinitis and asthma. Mean airway tissue concentration of NO (Caw(NO)), airway transfer factor for NO (Daw(NO)), mean alveolar concentration of NO (Calv(NO)) and fractional exhaled concentration of NO at a flow rate of 50 mL s(-1) ( FENO0.05) were determined using the extended NO analysis.Results: IgE-sensitised subjects had higher levels ( geometric mean) of FENO 0.05 (24.9 vs. 17.3 ppb) ( p < 0.001), Daw(NO) ( 10.5 vs. 8 mL s(-1)) ( p = 0.02) and Caw(NO) (124 vs. 107 ppb) ( p < 0.001) and positive correlations were found between the sum of specific IgE and FENO 0.05, Caw(NO) and Daw(NO) levels ( p < 0.001 for all correlations). Sensitisation to cat allergen was the major determinant of exhaled NO when adjusting for type of sensitisation. Rhinitis and asthma were not associated with the increase in exhaled NO variables after adjusting for the degree of IgE sensitisation.Conclusion: The presence of IgE sensitisation and the degree of allergic sensitisation were related to the increase in airway NO transfer factor and the increase in NO concentration in the airway wall. Sensitisation to cat allergen was related to the highest increases in exhaled NO parameters. Our data suggest that exhaled NO is more a specific marker of allergic inflammation than a marker of asthma or rhinitis.
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