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At least 721 records · Page 40Linked to original sources
PubMed2002

[Concentration of nitric oxide in exhaled air in patients with sarcoidosis--pilot study].

Exhaled nitric oxide (eNO) concentration measurement may allow for noninvasive estimation of severity of airways inflammation in asthma and other airways diseases. The purpose of this study was to evaluate usefulness of eNO concentration measurements in patients with pulmonary sarcoidosis. Study group consisted of 22 patients with sarcoidosis (8 women, 14 men aged 26-46). They included 11 patients with radiographically stage I and II and 11 patients with stage III of disease. Sixteen patients had active pulmonary sarcoidosis and 6 had nonactive disease. Ten patients had indications for treatment, 12 patients had not any. Exhaled NO was measured by means of SIEVERS 280 Nitric Oxide Analyser (USA). There was no significant difference in mean eNO concentration in study group (6.91 +/- 0.60 ppb) and in normal control (5.2 +/- 0.73 ppb, p = 0.10). Exhaled NO concentration was similar in patients with sarcoidosis stage I and II (7.5 +/- 1.08 ppb) and in patients with stage III disease (6.2 +/- 0.51 ppb, p = 0.27). We failed to found significant difference in eNO concentration between patients with active (6.7 +/- 0.71 ppb) and nonactive sarcoidosis (7.5 +/- 1.1 ppb; p = 0.57). Neither did eNO concentration differ between patients with and without indications for therapy (5.77 +/- 0.50 ppb vs. 7.8 +/- 0.95 ppb; p = 0.08). In conclusion our pilot study results indicate that measurement of eNO concentrations may be of little value in patients with sarcoidosis.

Adult↗
PubMed2002

Markers of pulmonary diseases in exhaled breath condensate.

Exhaled breath condensate has been more and more extensively used as a novel and non-invasive method to study airway inflammation. It is simple to perform, very well tolerated by patients and no adverse events have been reported so far. Serial measurements can be made with no harmful effects on patients, which is of extreme value in occupational medicine. Exhaled breath condensate has been obtained from both adult and children patients suffering from various pulmonary diseases such as asthma, cystic fibrosis, chronic obstructive pulmonary disease, and interstitial lung diseases. Several markers and mediators are detectable in breath condensate: hydrogen peroxide, thiobarbituric acid-reactive substances, isoprostanes, prostaglandins and leukotrienes. Nitric oxide-related markers have also been studied in the condensate. There is increasing body of evidence that changes in condensate markers reflect local abnormalities of airway lining fluid.

Adult↗
PubMedDate not supplied

Exhaled nitric oxide as a marker of adverse respiratory health effect in environmental disease.

The presence of, and the possibility to assay, nitric oxide (NO) in exhaled breath of humans caused a great deal of interest in relation to understanding the physiological and pathophysiological role of this molecule. Most studies have measured exhaled NO by chemiluminescence and detection depends on the photochemical reaction between NO and ozone generated in the analyzer. Here we discuss the role of exhaled NO as a physiological method to evaluate the effect of environmental changes on lower and upper airways in healthy subjects; particularly, its potential application as non invasive marker of the effect of outdoor and indoor air pollution on the respiratory tract.

Air Pollutants↗
PubMed2003

[Markers of lung disease in expired air].

Many chronic inflammatory pulmonary diseases are associated with inflammation and oxidative stress. A complex interplay between the specific cause of the diseases, the type and intensity of inflammation and oxidative stress, results in the clinical picture and reveals the probability of progression of the specific disease. The presence of inflammation and oxidative stress has been established in interstitial lung diseases, cystic fibrosis, bronchiectasis, adult respiratory distress syndrome, chronic obstructive lung diseases and asthma. Noninvasively obtained markers of inflammation and oxidative stress from the breath may assist in diagnosis of pulmonary diseases, assessment of diseases severity and response to treatment. Exhaled markers include NO, CO, H2O2, ethane, pentane, and isoprostanes.

Biomarkers↗
PubMedDate not supplied

Exhaled biomarkers in COPD: their potential role in diagnosis, treatment and prognosis.

Several diagnostic tools have been developed for diagnosing, monitoring and evaluating Chronic Obstructive Pulmonary Disease (COPD). There is an increasing interest in the use of non or less invasive biological markers (biomarkers) which reflect the character and intensity of the pathological processes in the lungs of COPD patients. The main goal of this review was to discuss the origin and current role of exhaled biomarkers in the diagnosis, evaluation of treatment and prognosis of COPD. Data of cross-sectional, cohort and intervention studies on exhaled biomarkers were studied. These studies were identified by a Medline search on papers in the English language published from 1990 to November 2001. The following markers were discussed: exhaled nitric oxide (NO), exhaled carbon monoxide (CO), exhaled alkanes, exhaled hydrogen peroxide (H2O2), exhaled isoprostanes, exhaled NO metabolites and exhaled thiobarbituric acid-reactive substances (TBARs). Data on these markers were summarized. The origin of each marker, the technique of analysis, the values in healthy controls and COPD patients, the effect of treatment and the correlation with other parameters were presented. Most studies, however, were cross-sectional studies with small populations. It was also difficult to compare studies because of differences in technique and study population. This review shows that exhaled biomarkers need to be studied further before using them in clinical practice. There is a need for standardization of the measurements, for comparison of COPD patients with healthy persons matched for age and smoking-status, for data on reproducibility and variability of all markers, for correlation of exhaled markers with other parameters and for intervention studies.

Biomarkers↗
PubMed2003

[Importance of determining hydrogen peroxide in expired air in the evaluation of oxidative lung damage].

Classical methods of respiratory diagnosis were extended with methods allowing determination of the metabolic products from lung tissue--the biochemical analysis of expired air. Hydrogen peroxide is one of the substances used as markers of pathological processes in the respiratory system. This review describes position of hydrogen peroxide in the metabolic pathway of reactive oxygen species, methods of hydrogen peroxide measurement in expired air and changes in hydrogen peroxide production in lung diseases.

Biomarkers↗
PubMed2003

The importance of exhaled air condensate in assessing the oxidant-antioxidant system in patients with chronic obstructive pulmonary disease.

The aim of this study was to investigate the relationship between selected lipid peroxidation products as markers of oxidative stress and antioxidant defense capacity in exhaled air condensate in comparison to blood and COPD severity. We detected that the increase of lipids peroxidation products in exhaled air condensate (less in blood) was accompanied by the reduction of total antioxidant capacity (antiradical activity and ceruloplasmin) according to the severity of COPD. Thus, the level of malondialdehyde significantly increased both in blood and exhaled air condensate in COPD1,2,3 (by 24%, 86%, 100% and 58%, 92%, 2,3 times respectively). Antiradical activity level was significantly decreased both in blood and exhaled air condensate in patients with COPD2,3 by 24%, 51% and 23.31% respectively. The results of this study clearly demonstrated the imbalance in oxidant-antioxidant system in advanced COPD.

Adult↗
PubMed2003

Comparison of exhaled breath condensate from nasal and oral collection.

BACKGROUND: Analysis of exhaled breath condensate may provide new insights into pulmonary inflammatory processes. A new collection method via suction of nasally expired air especially suitable for younger children was presented recently. Here we compare this nasal suction method with the more widely used oral collection method regarding the amount of condensate collected as well as the concentrations of hydrogen peroxide (H2O2), nitrite and nitrate, respectively. MATERIALS AND METHODS: Exhaled breath condensate was collected from 11 healthy adults for the measurements of the amount of condensate and H2O2 concentration and from 17 children for the measurements of nitrite and nitrate. Condensate was collected via nasal suction and oral exhalation from each subject. RESULTS: Overall, no differences between both collection methods were found for all variables assessed except the concentration of H2O2, whereas the latter closely correlated (Spearman r = 0.88, p = 0.0007) between both collection methods. No correlation was found for the amount of condensate collected and the concentration of nitrite and nitrate. The Bland-Altman limits of agreement scattered over a wide range with clinical impact, proving significant differences between both collection methods for all variables measured. CONCLUSIONS: Although nasal and oral collection method proved again suitable for the collection of exhaled breath condensate, the variability of the results obtained precludes the interchangeable usage of the inflammatory markers assessed here.

Adult↗
PubMed2003

[Exhaled breath condensate and its analysis--a new method in pulmonology].

In the middle of the nineties a new, non-invasive method for investigation of the lung aroused the interest of many researchers: the exhaled breath condensate. It shows the extent of the interest that in the last five years more than 80 original articles have been published in this theme. Many substances are found in the expired breath which are detectable in the liquid that we obtain by cooling (= condensing) the exhaled breath. The advantages of this method are that it is non-invasive, convenient, it could be performed with mechanically ventilated patients as well as with children. The most studied substance is the hydrogen-peroxide, which is the marker of oxidative stress, and its level in condensate is elevated in numerous inflammatory diseases. 8-isoprostane was also studied a lot, which is another marker of oxidative stress. Numerous substances could be even measured in condensate, so the decay-product of nitric-oxide (nitrite, nitrate, nitrotyrosine), further nitrosothiol, adenosine, ammonia, different ions, leukotrienes, cytokines; recently even other feature of condensate is examined, such as its pH. The different mediators could help us to know better the diseases, support the diagnosis, follow the treatment or the disease. In this study the authors attempt to present the most important knowledge till now.

Asthma↗
PubMed2003

[Concentration of nitric oxide exhaled air (eNO) in patients with COPD and bronchiectasis].

UNLABELLED: Exhaled nitric oxide (eNO) concentration measurement may allow for noninvasive estimation of severity of airways inflammation in respiratory tract diseases. Exhaled nitric oxide concentration is a sensitive marker of bronchial inflammation in asthma. The purpose of this study was: to evaluate eNO concentration in patients with COPD and bronchiectasis; to evaluate correlation between eNO concentration and the degree of airways obstruction in patients with COPD as well as correlation between eNO and extent of bronchiectasis in HRCT; to evaluate the effect of smoking on eNO concentration in COPD group. There were two groups of patients and the control group. The first group consisted of 20 patients with COPD (17 men, 3 women aged 41-68 yr). Ten patients were ex-smokers, and ten were current smokers. The second group consisted of 15 nonsmokers (10 men, 5 women aged 45-72 yr) with the diagnosis of bronchiectasis based on high-resolution CT criteria. The control group consisted of 11 healthy, nonsmoking subjects who had no respiratory disease or allergy, aged 28-52 years. Exhaled NO was measured by means of SIEVERS 280 Nitric Oxide Analyser (Boulder, Colorado, USA). RESULTS: The highest eNO concentration was found in patients with bronchiectasis (9.83 ppb +/- 3.09; median 8.0). It was significantly elevated compared to the values found in patients with COPD (5.3 ppb +/- 0.57, median 4.46; p = 0.002) or in the control group (5.17 ppb +/- 0.73, median 4.32; p = 0.007). Ex-smokers with COPD had higher eNO levels (6.3 ppb +/- 0.73; median 5.7) than did active smokers with COPD (4.3 ppb +/- 0.80; median 3.39; p = 0.017). Exhaled NO did not differ between exsmokers and healthy nonsmokers. There was no correlation between eNO and number of packyears (r = -0.022; p = 0.928). The extent of bronchiectasis expressed as CT score did not correlate with eNO concentration. There was also no significant relationship between eNO and FEV1 (r = -0.046; p = 0.87).

Adult↗
PubMed2004

[Significance of nitric oxide for patients with asthma].

Scientific knowledge about general importance of nitric oxide has considerably increased. In the field of respiratory medicine this comprehensive research has achieved already very useful and practical form in diagnostics of asthma. Nitric oxide belongs to non-specific markers of inflammation. Despite the measurement of exhaled nitric oxide has only limited significance for diagnosis of asthma, it is very useful for monitoring of inflammatory process. This method is also suitable for the control of effectiveness of the antiinflammatory treatment. In some developing countries. measurement of concentration of exhaled nitric oxide in asthmatic patients is already used in fields between research and clinical practice. Author reviewed the recent information with the emphasis on clinical relevance.

Asthma↗
PubMed2004

Leukotriene-B4 concentrations in breathing condensate before and after simulated deep dives.

During diving the respiratory tract is exposed to occupational hazards (increased oxygen partial pressure, pulmonary vessel engorgement during submersion, inert gas micro embolism during decompression). Leukotriene-B4 [LTB4] concentrations in the exhaled breath mirrors the inflammatory activity of the airways if the respiratory tract has been exposed to occupational hazards. In this study LTB4-concentrations in the exhaled breath and spirometry data obtained before and after simulated dives helped to elucidate any contributions by hyperbaric exposure to impaired lung function and to separate effects of ambient pressure from those of submersion and increased oxygen partial pressure. Thirty two healthy subjects carried out dives in a hyperbaric chamber using a cross over design to 600 kPa ambient pressure with and without submersion and a dry exposure to pure oxygen at 120 kPa ambient pressure (durations: 43 min). Pre-dive and four hours after surfacing the exhaled breath was collected non-invasively. Condensate was measured by a standard enzyme immuno-assay for LTB4 in parallel with lung function values (FVC, FEV1, MEF 25-75). Pre-exposure baseline values of LTB4-concentrations and lung function values were in the normal range. Post-exposure values did not differ significantly from the baseline values. The data gave no evidence of any inflammatory activity in the subjects' airways after hyperbaric exposure.

Adult↗
PubMed2004

[Examination of exhaled breath condensate in patients with asthma and chronic obstructive pulmonary diseases].

Considerable interest of specialists all over the world has focused on the measurement of the markers of inflammation and oxidative stress in the exhaled breath condensate in patients with asthma or chronic obstructive pulmonary diseases recently. Use of exhaled condensate is based on the hypothesis that aerosol particles exhaled in human breath reflect the composition of the bronchoalveolar extracellular lining fluid. The standard collection of the material requires condensation of exhaled air and the samples have to be kept in biologically inert containers. Measurement of the very low concentrations of selected substances requires very sensitive analytical methods. The examination of exhaled breath condensate is absolutely non-invasive method, which can be repeated as often as needed and it is extremely well tolerated both by children and seniors. Markers in the condensate enable detection and quantification of the inflammation process, the disease monitoring, and assessment of the response to the treatment. The breath condensate diagnostics is a new progressive method and in the patients with asthma and chronic obstructive pulmonary disease it can bring complementary information to the very sensitive method of determination of exhaled nitric oxide.

Asthma↗
PubMed2004

Exhaled carbon monoxide is not flow dependent in children with cystic fibrosis and asthma.

STUDY OBJECTIVES: Exhaled nitric oxide (eNO) and carbon monoxide (eCO) concentrations are elevated in inflammatory airway diseases like asthma and have been investigated as potential diagnostic markers. For eNO concentrations knowledge about the inverse flow dependency is essential for reproducibility and comparability of measurements. The aim of this investigation was to evaluate a possible expiratory flow dependency of eCO in children with different inflammatory airway diseases. DESIGN: ENO and eCO concentrations were measured electrochemically and via chemiluminescence in the exhaled air of 20 healthy children, 17 stable cystic fibrosis (CF)-patients and 15 steroid-naive asthmatics in a combined analyzer at five different expiratory flows (10, 20, 45, 86, 184 ml/sec). RESULTS: ECO was not flow dependent in any of the three groups. At 45 ml/sec the mean eCO-concentration of healthy children was 3.72 +/- 0.23 ppm, of CF-patients 3.67 +/- 0.37 ppm and of asthmatics 4.99 +/- 0.45 ppm. Elevated eCO (p<0.0122) was found in asthmatics but not in CF-children. There was no age dependency and no correlation between eNO and eCO. CONCLUSIONS: In contrast to CF-patients in the exhaled air of steroid-naive asthmatics elevated eCO concentrations are found that may serve as non-invasive inflammatory marker. In contrast to eNO, eCO did not show any expiratory flow dependency.

Adolescent↗