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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Technological Advancements in Breath Analysis

de Silva, Geethanga January 2016 (has links)
No description available.
2

Évaluation méthodologique et clinique des marqueurs de l’atteinte pulmonaire dans l’air exhalé : comparaison de sujets présentant une pathologie respiratoire chronique et sujets témoins / Methodological and clinical evaluation of markers of the lung injury in exhaled breath : comparison of subjects with chronic respiratory disease and controls

Kornobis-Chérot, Nathalie 17 July 2012 (has links)
Un accès direct et non invasif à la pathogénèse par l’évaluation de biomarqueurs volatils (FeNO) ou non volatils de l’air exhalé grâce à la méthode des condensats de l’air exhalé (EBC) est utile pour estimer précocement le degré d’atteinte pulmonaire en rapport avec une exposition professionnelle et surveiller son évolution en regard des mesures correctives mises en place. L’étude du NO exhalé (FeNO) est actuellement bien standardisée et l’augmentation exponentielle des publications concernant les EBC reflètent un intérêt croissant pour le diagnostic non invasif des atteintes pulmonaires. Les marqueurs étudiés dans l’air exhalé sont des produits de l'inflammation tels que le FeNO et les cytokines ainsi que des produits du stress oxydant incluant le peroxyde d'hydrogène, les produits de peroxydation lipidique (8-isoprostane, malondialdehyde) et les oxydes d'azote (NOx). S’agissant d’une technique d’exploration relativement récente, les modalités méthodologiques font encore l’objet de nombreux travaux, les premières recommandations internationales étant apparues en 2005. Les écueils méthodologiques sont nombreux et encore décrits dans la littérature en 2012. Ils concernent toutes les étapes du processus du recueil et d’analyses.Objectifs : L’objectif principal de notre recherche était dans un premier temps de développer la méthode des EBC pour l'étude des composés de l'air exhalé puis de détecter et quantifier des biomarqueurs tels que les protéines totales, les NOx et le 8-isoprostane dans les EBC d’une population d’adultes sains (n= 48) ou atteints de pathologies pulmonaires telles que l'asthme (n=24), la BPCO (n=20), la pneumopathie interstitielle diffuse (n=27) et la sclérodermie (n=27). L’objectif secondaire était la comparaison des niveaux de biomarqueurs dosés dans les EBC et du FeNO chez les sujets malades par rapport aux témoins.Résultats / Conclusion : Notre recherche, soutenue l’ANR et l’ANSES, a permis de standardiser la méthodologie de recueil et d’analyse des EBC avec une optimisation du système de recueil et de l’agent coatant pour la détermination de la concentration nécessaire et compatible avec les analyses. Nous maitrisons le dosage dans les EBC des biomarqueurs tels que les protéines, les NOx et le 8-isoprostane. D'autres biomarqueurs sont encore en cours d'étude tels que le malondialdehyde et les cytokines. Ce travail méthodologique, publié, a permit dans un second temps la détection (> à 95%) et la quantification de ces biomarqueurs dans les EBC des sujets sains et malades de notre population.Perspectives : La constitution des valeurs de référence pour les biomarqueurs dosés dans les EBC est nécessaire à l’interprétation des dosages chez les sujets malades. Il convient également de finaliser la standardisation de la mesure des cytokines et du malondialdehyde et d’explorer de nouveaux biomarqueurs produits lors du stress nitrosant tels que la 3-nitrotyrosine pour compléter les mécanismes physiopathologiques. Enfin le développement de cette méthode non invasive et peu contraignante apparait prometteuse en clinique médicale dans le suivi individuel de la maladie ou son traitement comme lors d’études épidémiologiques respiratoires dans des populations exposées professionnellement ou environnementalement. Dans ce cadre, l’étude de marqueurs d’exposition professionnelle tels que les métaux lourds dans les EBC est en cours de développement. / The study of both volatile (FeNO) and non-volatile respiratory biomarkers using the method of exhaled breath condensates can be useful in medical surveillance of exposed workers, the early identification of respiratory diseases or in the monitoring of their development. Studies of exhaled NO (FeNO) is now well standardized and the exponential increase in publications on exhaled breath condensate (EBC) reflects growing interest in a non-invasive diagnosis of pulmonary diseases. The biomarkers studied are products of inflammation, such as FeNO and cytokines, and products of oxidative stress, including hydrogen peroxide (H202), products of lipid peroxydation (8-isoprostane, malondialdehyde) and nitrogen oxides. The first recommendation was published in 2005 but although many recent publications have applied this new method, numerous methodological pitfalls remain and still described in 2012. They concern all the stages of the collection to the analysis.Objectives: The main objective of this research was initially to develop the method of EBC for the study of compounds of exhaled air and then detect and quantify biomarkers such as total protein, NOx and 8-isoprostane in exhaled air in a population of healthy adults (n = 48) or patients with lung inflammatory diseases such as asthma (n = 24), COPD (n = 20), diffuse interstitial pneumonia (n = 27) and scleroderma (n = 27). The secondary objective was to compare levels of biomarkers measured in the EBC and FeNO in patients compared to controls.Results / conclusion: Our research, supported by ANR and ANSES, allowed to standardize the methodology of collection and analysis of EBC with a choice of the collection system and coating which must be effective and compatible with the analyzes. In EBC, we control the dosage of biomarkers such as proteins, NOx and 8-isoprostane. Other biomarkers are still being studied such as malondialdehyde and cytokines. This published methodological study, allowed in a second step the detection (> 95%) and quantification of these biomarkers in EBC of healthy patients in our population.Perspectives: This standardization is a key epidemiological requirement for the task force on the establishment of reference values and the publication of methodological guidelines so as to realize the promise of this approach for clinical studies of lung diseases. We have also to finish the development of biomarkers such as cytokines or malondialdehyde and to investigate new biomarkers to complete the pathophysiological mechanisms. Finally our objective is the widespread use of this noninvasive method in daily epidemiological studies on subjects with professional and/or environmental exposure. In this context, the study of markers of the toxic burden in the lungs such as heavy metals in the EBC is being developed.
3

Non-invasive measurement of markers of oxidative stress in asbestos-related lung diseases and pulmonary fibrosis

Chow, Sharron Sau Ming, Medical Sciences, Faculty of Medicine, UNSW January 2009 (has links)
Background and objective: Asbestos can cause various pulmonary diseases including asbestosis, pleural plaques and pleural thickening. Animal and in vitro studies suggest that the toxicity of asbestos is due to the iron content of the fibres which not only generate oxidants directly, but also activate the inflammatory cells in the lung that contribute to oxidative stress. This study therefore sought to establish data in man to corroborate the animal and in vitro evidence. Exhaled breath condensate (EBC) collection is a novel, non-invasive technique to collect samples from the lung for investigating inflammatory biomarkers of lung diseases. This technique is harmless, rapid and easily repeatable which leads itself to the investigation of lung diseases such as asbestos-related diseases and pulmonary fibrosis (PF) that are otherwise difficult to study. The hypothesis tested was that oxidative and nitrosylative stress markers will be elevated in the EBC of patients with asbestos-related diseases and PF compared to normal control subjects. Methods: The study design was a cross-sectional and observational in vivo study whereby EBC was collected and fractional exhaled nitric oxide (FeNO) and carbon monoxide (eCO) were measured. EBC markers including pH, hydrogen peroxide (H2O2), total nitrogen oxides (NOx), 3-nitrotyrosine (3-NT), 8-isoprostane (8-iso), total protein and transforming growth factor-β1 (TGFβ1) were measured by microelectrode analysis, colorimetric and enzyme immunoassays. 3-NT and 8-iso were further examined by immunohistochemical techniques in samples of lung tissue. Results: Subjects with asbestosis had significantly raised levels of EBC H2O2, 8-iso, total protein and FeNO compared with healthy individuals. The same markers except H2O2, but with 3-NT and eCO were again significantly increased in those with other causes of PF, compared with control subjects. Heavy nitrotyrosine staining was found on the lung sections from patients with asbestosis and PF. Conclusions: This study confirmed that increased production of reactive oxygen and nitrogen species is associated with asbestos exposure and pulmonary fibrosis in vivo confirming animal and in vitro studies. Analysis of EBC may prove a useful non-invasive tool in exploring the basic pathophysiology of lung diseases in clinical research and may in the future be used to monitor progress in asbestosis and pulmonary fibrosis.
4

Exhaled breath analysis in exercise and health

Heaney, Liam M. January 2016 (has links)
Research in the field of exhaled breath analysis is developing rapidly and is currently focussed on disease diagnosis and prognosis. The ability to identify early onset of life-threatening diseases, by a subtle change in exhaled profile that is picked up through a non-invasive measure, is of clinical interest. However, implementation of exhaled breath analysis can extend further beyond disease diagnosis and/or management. Using a non-invasive and rapid sample collection with high sensitivity, breath analysis may be seen to have potential benefit to the wider community. This research describes preliminary investigations into exhaled breath in exercise-based scenarios that aims to translate current breath analysis methodologies into a sport and exercise medicine context. An adaptive absorbent-based breath sampling methodology was used to collect a total of 220 breath samples from 54 participants over 3 studies. Breath volatiles were analysed using thermal desorption-gas chromatography-mass spectrometry. Data were analysed with targeted, and multivariate metabolomics-based approaches. Potential health impacts to high performance and recreational swimmers exposed to chlorinated water was studied. Following preliminary and scoping studies, 19 participants were sampled before a 30 min swim, and a further 5 times for 10 hrs after swimming. Environmental and control samples were also collected. Concentrations of chlorine-based disinfection by-products were observed to increase by up to a median of 121-fold, and take up to 8.5 hrs to return to pre-swimming levels. Metabolomic profiling identified the monoterpene geranylacetone to be a discriminant variable in samples taken 10 hrs after swimming. Geranylacetone is associated with membranes and extracellular fluids and an upregulated trend was observed across the five sampling time points post-swimming. Further research with an appropriately stratified and powered cohort (n=38) was recommended. The effects of intense exercise on breath profiles was explored for the possible use of breath analysis for exercise science with elite performance-based medicine. Twenty-nine participants provided exhaled breath samples before undergoing a maximal oxygen uptake (fitness) test and then provided 2 additional samples over the following 1 hr period. High and low fitness groupings, deemed by oxygen uptake values, were compared for exhaled metabolites. Lower exhaled acetone and isoprene were observed in participants with greater absolute oxygen uptake leading to a hypothesis for a non-invasive breath based fitness test. Finally, an interface for breath-by-breath analysis using a transportable mass spectrometer was developed. A controlled change in exhaled profiles was achieved through the ingestion of a peppermint oil capsule. Menthone was measured on-line and monitored for up to 10 hrs post-administration. Sixteen participants enabled the system to be demonstrated as exhaled menthone was at elevated concentrations for at least 6 hrs. Validation against thermal desorption-gas chromatography-mass spectrometry confirmed the system to be detecting metabolites at the sub-μg L-1 range.
5

Nitric oxide in airway inflammation

Liu, Jia, Clinical School - Prince of Wales Hospital, Faculty of Medicine, UNSW January 2009 (has links)
Exhaled breath condensate (EBC) is a non-invasive method of investigating airway inflammation associated with nitric oxide (NO) and the metabolites nitrite/nitrates (NOx) in diseases such as chronic obstructive pulmonary disease (COPD), but some of the variables affecting the results are unknown. It was hypothesised that 1) EBC would be influenced by lung volumes and the type of EBC collection device; 2) fractional exhaled NO (FENO) and EBC NOx in COPD patients would be altered by smoking and glucocorticosteroids (GCS); 3) cigarette smoke could contribute to the EBC NOx concentration while it may also decrease FENO indirectly by converting airway NO to NOx. It was found that EBC volume was significantly correlated with both tidal volume and minute volume. Comparing four EBC collection devices demonstrated greater efficiency with the ECoScreen?? than siliconised glass tubes or RTube?? but it gave factitiously high NOx levels. Total EBC protein levels over a 10-minute collection were significantly higher using the ECoScreen?? than either glass or RTube?? devices. A cross-sectional study of 96 COPD patients and 80 age-matched control subjects demonstrated that FENO levels in COPD patients were significantly higher than normal subjects when comparing either the combined groups or appropriate two subgroups: ex-smokers and smokers. GCS treatment demonstrated no significant effect on either FENO levels or EBC NOx, but EBC NOx was elevated in smokers. In vitro, cigarette smoke extract (CSE) induced significantly higher NOx and asymmetric dimethylarginine (ADMA) levels in A549 cells when compared with control media. The anti-oxidant, NAC pre-treatment partially reversed the elevated NOx levels but not the ADMA levels. This thesis is the first to report FENO and EBC NOx in COPD patients in an appropriate sample size to be able to evaluate each subgroup, and the increased EBC NOx levels found in smokers in vivo was consistent with the elevated NOx level in response to CSE observed in vitro. These data indicate that smoking-related airway inflammation and activation of the NO pathway are complex with both an increase in ADMA, NO, NOx and may be regulated by oxidative stress rather than the nitric oxide synthase (NOS) pathway.
6

Low-Flow Domiciliary Oxygen as a Mechanism of Ongoing Oxidative Stress in COPD Patients

Stulce, Jill 01 January 2015 (has links)
Healthcare costs are escalating in the U.S., with a projected 48 trillion dollars by 2021. More than ever medical researches are obligated to ensure that costly treatment modalities are safe and effective. Chronic obstructive pulmonary disease (COPD) is a costly and debilitating disease, ranked as the third leading cause of death in America. Currently, treatment for COPD consists of anti-inflammatory agents, bronchodilators, antibiotics and supplemental oxygen when hypoxemia or clinical manifestations ensue. Oxidative stress is central to the pathology of COPD. Supplemental oxygen has been substantiated as an instigator of oxidative stress; however, LFDO has not been evaluated as a mechanism of ongoing oxidative stress in individuals with COPD. Isofuran (IsoF), a biosynthetic relative of the validated oxidative stress biomarker 8-isoprostane, is preferentially synthesized during periods of increased tissue oxygen tension. This sort of specificity allows for refinement in the assessment of supplemental oxygen as a source of oxidative stress. To address this potential this study evaluated individuals diagnosed with COPD utilizing LFDO. The study also aimed to determine if IsoF possessed clinical application in predicting the standard pulmonary function test (PFT) parameters of FEV1, FVC, FEV1/FVC and FEF25-75. The exhaled breath condensate (EBC) of 52 individuals with COPD was evaluated for the presence of IsoF. An active control group not receiving LFDO (n=26) was compared to an active treatment group receiving LFDO for a minimum of 6 hrs/day (n=26). The groups showed no statistically significant demographic differences in age, gender, height, weight, ethnicity or smoking history or in the pulmonary function test parameters of FEV1, FVC, and FEV1/FVC, with the exception of the FEF25-75 (P=0.03). The active control group generated a mean EBC IsoF level of 35.81 ± 4.91 pg/ml (± SEM) compared to the active treatment group mean EBC IsoF level of 51.37 ± 8.27 pg/ml (P=0.057). Currently, no research has been conducted that defines baseline EBC IsoF levels in healthy or diseased lungs. No statistically significant differences in mean EBC IsoF levels were noted between the control and treatment groups; however, the results, in conjunction with the only two studies available utilizing EBC IsoF as an oxidative stress biomarker, may serve to provide benchmark information for future research regarding individuals with diseased lungs, specifically COPD.
7

Desenvolvimento de um aparato para a coleta do condensado do exalado pulmonar visando a análise do óxido nítrico em indivíduos hígidos / Development of an apparatus for the collection of Exhaled Breath Condensate in order to analysis of Nitric Oxide in healthy subjects

Vento, Daniella Alves 02 September 2011 (has links)
O óxido nítrico (NO) tem papel relevante nas diversas funções fisiológicas do organismo e nos mais variados sistemas que o compõe. Sabe-se que esta molécula é um constituinte normal do ar exalado na respiração de humanos e de animais. Tem como funções modular respostas inflamatórias e imunes bem como atuar na regulação do tônus vascular da musculatura lisa das vias aéreas. Esta molécula vem sendo reconhecida como importante marcador de lesão pulmonar, o que despertou a intensa investigação do NO no ar exalado. Uma metodologia não invasiva, de baixo custo e de fácil aplicação está sendo extensivamente estudada para a captação do ar exalado através do seu resfriamento e condensação, denominada Condensado do Exalado Pulmonar (CEP). É grande o interesse no estudo de doenças pulmonares inflamatórias, no entanto, observa-se uma considerável carência de evidências acerca dos níveis de concentração de mediadores inflamatórios, como o NO em amostras de indivíduos hígidos utilizando o CEP. Diante disso, decidiu-se elaborar um protótipo de aparato para coleta do condensado e empregar esta técnica para determinar valores de concentração de NO em uma amostra de voluntários hígidos. A metodologia de coleta utilizada foi baseada nas recomendações da força tarefa da American Thoracic Society/European Respiratory Society (ATS/ERS) para procedimentos de coleta de condensado, com o intuito de evitar erros metodológicos, padronizar e trazer mais evidências para auxiliar a inserção do método na rotina clínica, além de disponibilizá-lo para novas pesquisas. Para isto foram selecionados 116 indivíduos adultos hígidos de ambos os sexos, com idade entre 20 e 70 anos. O protótipo de aparato utilizado na pesquisa foi de fabricação artesanal e desenvolvido na Divisão de Cirurgia Torácica e Cardiovascular da Faculdade de Medicina da Universidade de São Paulo- FMRP/USP, visto que os aparatos comerciais são todos importados, de custo elevado e que ainda não forneceram evidências suficientes de que algum destes seria o padrão ouro para a coleta. O aparato foi eficiente para coletar o CEP e o NO foi detectável em todas as amostras. A média de NO foi de 13±14,4µM, e não houve correlação com o gênero (p=0,847) e idade (p=0,811). Não foi observado correlação entre o NO e o volume de CEP coletado (p=0,944). O volume de CEP coletado é dependente do volume exalado total (p<0,001). A partir destes resultados pode-se verificar que o aparato é viável e eficiente. Não foram encontradas correlações entre a concentração de NO no CEP, idade e o gênero. O presente estudo poderá contribuir com futuras pesquisas de caráter comparativo e fornecer mais uma opção de aparato para coleta do condensado do exalado pulmonar, provendo baixo custo, reprodutibilidade e reutilização do aparato / Nitric oxide (NO) plays an important role in various physiological functions in the body and in various systems that compose it. It is known that this molecule is a normal constituent of exhaled breath in humans and animals. Its functions modulate inflammatory and immune responses as well as act in the regulation of vascular tone of smooth muscles of the airways. This molecule has been recognized as an important marker of lung injury, which sparked intense investigation of exhaled NO. A non-invasive method, low cost and easy application has been extensively studied to collect the exhaled air through its cooling and condensation, termed exhaled breath condensate. There is great interest in the study of inflammatory lung diseases, however, there is a considerable lack of evidence about the concentration levels of inflammatory mediators such NO in samples of healthy individuals using exhaled breath condensate. Given this, it was decided to develop a prototype apparatus for collecting exhaled breath condensate (EBC) and employ this technique to determine concentration values of nitric oxide in a sample of healthy volunteers. The sampling methodology based on the recommendations of the task force of the American Thoracic Society / European Respiratory Society (ATS / ERS) for procedures using for collection of condensate, in order to avoid methodological errors, standardize and bring more evidence to support the inclusion of the method in clinical routine, and make it available for further research. We selected 116 healthy adults of both gender, aged between 20 and 70. The prototype apparatus used in the research was designed, produced and developed in the Division of Thoracic and Cardiovascular Surgery, Faculty of Medicine, University of São Paulo-FMRP / USP. The commercial devices are all imported, expensive and not yet provided sufficient evidence that any of these would be the gold standard for collection. The apparatus was efficient to collect the EBC and NO was detectable in all samplesThe average NO was 14.4 ± 13 µM, and there was no correlation with gender (p = 0.847) and age (p = 0.811). There was no correlation between NO and the volume of collected EBC (p = 0.944). The volume of collected EBC is dependent on the total exhaled volume (p <0.001). From these results it can be seen that the apparatus is feasible and efficient. No correlation was found between the concentration of NO in the EBC, age and gender. The present study may contribute to future comparative studies of character and provide another option for apparatus for collecting condensate, providing low cost, reliability and reusability of the apparatus
8

Breath biomarkers associated with lung cancer

Tran , Vanessa Hoang, Medical Sciences, Faculty of Medicine, UNSW January 2009 (has links)
Lung cancer (LC) is often diagnosed at advanced stage and as a result, survival rates are low. Recent studies describe exhaled breath and exhaled breath condensate (EBC) as a potential non-invasive method of sampling the airways for assessing inflammation of the respiratory system, and possibly for the early detection of LC. It was hypothesised that higher concentrations of markers and protein will be present in the EBC of LC patients compared to those of normal controls and healthy smokers, and may aid in assessing lung status. Methods: The gaseous phase of breath was investigated for volatile organic compound (VOC) patterns using an electronic nose (eNose) system, in addition to off-line measurements of carbon monoxide (CO) and nitric oxide (NO) levels. The aqueous phase, EBC, was collected during tidal breathing through a glass collection device cooled to 4??C by ice. Nitrite/nitrate (NOx) and pH levels were determined by a fluorescent modification of the Griess method, and silicon chip sensor pH meter, respectively. Protein levels in EBC were examined with a bicinchoninic acid (BCA) assay, silver staining and PAGE techniques, while the levels of tumour markers, CYFRA 21-1 and CEA, were quantified by enzyme-linked immunosorbent assays (ELISA). Results: The eNose machine was not able to produce characteristic VOC profiles from exhaled breath unique to each study group, while no significant difference was observed for mean NOx concentrations in the LC group when compared to other subjects (p=0.8824). Higher protein levels were found in the EBC of LC patient compared to normal controls (p=0.0204), with subsequent measurements of elevated CEA levels observed in the LC group when compared to non-smokers and smokers (p=0.023). Conclusion: This study showed that protein can be detected in the exhaled breath condensate of patients, with a significantly elevated amount in the samples from newly diagnosed LC patients. The mechanism for these differences remains to be determined but may be related to inflammatory changes within the airway, such as vascular protein leakage and release of mediators. Future work may aim to identify the upregulated proteins, and focus on proteomics and tissue microarrays to explore candidate proteins.
9

Breath biomarkers associated with lung cancer

Tran , Vanessa Hoang, Medical Sciences, Faculty of Medicine, UNSW January 2009 (has links)
Lung cancer (LC) is often diagnosed at advanced stage and as a result, survival rates are low. Recent studies describe exhaled breath and exhaled breath condensate (EBC) as a potential non-invasive method of sampling the airways for assessing inflammation of the respiratory system, and possibly for the early detection of LC. It was hypothesised that higher concentrations of markers and protein will be present in the EBC of LC patients compared to those of normal controls and healthy smokers, and may aid in assessing lung status. Methods: The gaseous phase of breath was investigated for volatile organic compound (VOC) patterns using an electronic nose (eNose) system, in addition to off-line measurements of carbon monoxide (CO) and nitric oxide (NO) levels. The aqueous phase, EBC, was collected during tidal breathing through a glass collection device cooled to 4??C by ice. Nitrite/nitrate (NOx) and pH levels were determined by a fluorescent modification of the Griess method, and silicon chip sensor pH meter, respectively. Protein levels in EBC were examined with a bicinchoninic acid (BCA) assay, silver staining and PAGE techniques, while the levels of tumour markers, CYFRA 21-1 and CEA, were quantified by enzyme-linked immunosorbent assays (ELISA). Results: The eNose machine was not able to produce characteristic VOC profiles from exhaled breath unique to each study group, while no significant difference was observed for mean NOx concentrations in the LC group when compared to other subjects (p=0.8824). Higher protein levels were found in the EBC of LC patient compared to normal controls (p=0.0204), with subsequent measurements of elevated CEA levels observed in the LC group when compared to non-smokers and smokers (p=0.023). Conclusion: This study showed that protein can be detected in the exhaled breath condensate of patients, with a significantly elevated amount in the samples from newly diagnosed LC patients. The mechanism for these differences remains to be determined but may be related to inflammatory changes within the airway, such as vascular protein leakage and release of mediators. Future work may aim to identify the upregulated proteins, and focus on proteomics and tissue microarrays to explore candidate proteins.
10

Desenvolvimento de um aparato para a coleta do condensado do exalado pulmonar visando a análise do óxido nítrico em indivíduos hígidos / Development of an apparatus for the collection of Exhaled Breath Condensate in order to analysis of Nitric Oxide in healthy subjects

Daniella Alves Vento 02 September 2011 (has links)
O óxido nítrico (NO) tem papel relevante nas diversas funções fisiológicas do organismo e nos mais variados sistemas que o compõe. Sabe-se que esta molécula é um constituinte normal do ar exalado na respiração de humanos e de animais. Tem como funções modular respostas inflamatórias e imunes bem como atuar na regulação do tônus vascular da musculatura lisa das vias aéreas. Esta molécula vem sendo reconhecida como importante marcador de lesão pulmonar, o que despertou a intensa investigação do NO no ar exalado. Uma metodologia não invasiva, de baixo custo e de fácil aplicação está sendo extensivamente estudada para a captação do ar exalado através do seu resfriamento e condensação, denominada Condensado do Exalado Pulmonar (CEP). É grande o interesse no estudo de doenças pulmonares inflamatórias, no entanto, observa-se uma considerável carência de evidências acerca dos níveis de concentração de mediadores inflamatórios, como o NO em amostras de indivíduos hígidos utilizando o CEP. Diante disso, decidiu-se elaborar um protótipo de aparato para coleta do condensado e empregar esta técnica para determinar valores de concentração de NO em uma amostra de voluntários hígidos. A metodologia de coleta utilizada foi baseada nas recomendações da força tarefa da American Thoracic Society/European Respiratory Society (ATS/ERS) para procedimentos de coleta de condensado, com o intuito de evitar erros metodológicos, padronizar e trazer mais evidências para auxiliar a inserção do método na rotina clínica, além de disponibilizá-lo para novas pesquisas. Para isto foram selecionados 116 indivíduos adultos hígidos de ambos os sexos, com idade entre 20 e 70 anos. O protótipo de aparato utilizado na pesquisa foi de fabricação artesanal e desenvolvido na Divisão de Cirurgia Torácica e Cardiovascular da Faculdade de Medicina da Universidade de São Paulo- FMRP/USP, visto que os aparatos comerciais são todos importados, de custo elevado e que ainda não forneceram evidências suficientes de que algum destes seria o padrão ouro para a coleta. O aparato foi eficiente para coletar o CEP e o NO foi detectável em todas as amostras. A média de NO foi de 13±14,4µM, e não houve correlação com o gênero (p=0,847) e idade (p=0,811). Não foi observado correlação entre o NO e o volume de CEP coletado (p=0,944). O volume de CEP coletado é dependente do volume exalado total (p<0,001). A partir destes resultados pode-se verificar que o aparato é viável e eficiente. Não foram encontradas correlações entre a concentração de NO no CEP, idade e o gênero. O presente estudo poderá contribuir com futuras pesquisas de caráter comparativo e fornecer mais uma opção de aparato para coleta do condensado do exalado pulmonar, provendo baixo custo, reprodutibilidade e reutilização do aparato / Nitric oxide (NO) plays an important role in various physiological functions in the body and in various systems that compose it. It is known that this molecule is a normal constituent of exhaled breath in humans and animals. Its functions modulate inflammatory and immune responses as well as act in the regulation of vascular tone of smooth muscles of the airways. This molecule has been recognized as an important marker of lung injury, which sparked intense investigation of exhaled NO. A non-invasive method, low cost and easy application has been extensively studied to collect the exhaled air through its cooling and condensation, termed exhaled breath condensate. There is great interest in the study of inflammatory lung diseases, however, there is a considerable lack of evidence about the concentration levels of inflammatory mediators such NO in samples of healthy individuals using exhaled breath condensate. Given this, it was decided to develop a prototype apparatus for collecting exhaled breath condensate (EBC) and employ this technique to determine concentration values of nitric oxide in a sample of healthy volunteers. The sampling methodology based on the recommendations of the task force of the American Thoracic Society / European Respiratory Society (ATS / ERS) for procedures using for collection of condensate, in order to avoid methodological errors, standardize and bring more evidence to support the inclusion of the method in clinical routine, and make it available for further research. We selected 116 healthy adults of both gender, aged between 20 and 70. The prototype apparatus used in the research was designed, produced and developed in the Division of Thoracic and Cardiovascular Surgery, Faculty of Medicine, University of São Paulo-FMRP / USP. The commercial devices are all imported, expensive and not yet provided sufficient evidence that any of these would be the gold standard for collection. The apparatus was efficient to collect the EBC and NO was detectable in all samplesThe average NO was 14.4 ± 13 µM, and there was no correlation with gender (p = 0.847) and age (p = 0.811). There was no correlation between NO and the volume of collected EBC (p = 0.944). The volume of collected EBC is dependent on the total exhaled volume (p <0.001). From these results it can be seen that the apparatus is feasible and efficient. No correlation was found between the concentration of NO in the EBC, age and gender. The present study may contribute to future comparative studies of character and provide another option for apparatus for collecting condensate, providing low cost, reliability and reusability of the apparatus

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