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1.
Thorax ; 76(1): 86-88, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33097604

RESUMO

False negatives from nasopharyngeal swabs (NPS) using reverse transcriptase PCR (RT-PCR) in SARS-CoV-2 are high. Exhaled breath condensate (EBC) contains lower respiratory droplets that may improve detection. We performed EBC RT-PCR for SARS-CoV-2 genes (E, S, N, ORF1ab) on NPS-positive (n=16) and NPS-negative/clinically positive COVID-19 patients (n=15) using two commercial assays. EBC detected SARS-CoV-2 in 93.5% (29/31) using the four genes. Pre-SARS-CoV-2 era controls (n=14) were negative. EBC was positive in NPS negative/clinically positive patients in 66.6% (10/15) using the identical E and S (E/S) gene assay used for NPS, 73.3% (11/15) using the N/ORF1ab assay and 14/15 (93.3%) combined.


Assuntos
Testes Respiratórios/métodos , /diagnóstico , Expiração , RNA Viral/análise , /genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
2.
J Breath Res ; 14(4): 047104, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33021211

RESUMO

Exhaled breath aerosols contain valuable metabolomic content due to gas exchange with blood at the alveolar capillary interface in the lung. Passive and selective filtering of these aerosols and droplets may reduce the amount of saliva contaminants and serve as an aid to enhance targeted metabolomic content when sampled in exhaled breath condensate (EBC). It is currently unknown if breath aerosol size distribution affects the types or abundances of metabolites sampled through EBC. This pilot study uses a previously described hand-held human breath sampler device with varying notch filter geometries to redirect the trajectory of breath aerosols based on size. Ten notch filter lengths were simulated with the device to calculate the effect of filter length on the breath aerosol size distribution and the proportion of aerosols which make their way through to an EBC collection tube. From three notch filter lengths, we investigate metabolite content of various aerosol fractions. We analyzed the non-volatile fraction of breath condensate with high performance liquid chromatography-mass spectrometry for broad metabolite coverage. We hypothesize that: (1) increasing the length of the notch filter in this device will prevent larger aerosols from reaching the collection tube thus altering the breath aerosol size distribution sampled in EBC; and (2) there is not a systematic large-scale difference in EBC metabolomic content that correlates with breath aerosol size. From simulation results, particles typically larger than 10 µm were filtered out. This indicates that a longer notch filter in this device prevents larger particles from reaching the collection tube thus altering the aerosol particle size distribution. Most compounds were commonly present in all three filter lengths tested, and we did not see strong statistical evidence of systematic metabolite differences between breath aerosol size distributions.


Assuntos
Aerossóis/análise , Testes Respiratórios/métodos , Expiração , Metabolômica , Tamanho da Partícula , Adulto , Simulação por Computador , Humanos , Masculino , Metaboloma , Projetos Piloto
3.
J Breath Res ; 14(4): 046013, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33021204

RESUMO

Volatile organic compound (VOC) breath testing of lung and head and neck squamous cell carcinoma (SCC) has been widely studied, however little is known regarding VOC profiles of in-situ SCC. A prospective study of VOC in patients with histologically proven SCC, either in-situ or advanced, and controls. Breath samples were analysed using the E-nose Cyranose ®320 and by gas chromatography/mass spectroscopy. Predictive models were developed using bootstrap forest using all 32 sensors. Data from 55 participants was analysed: 42 SCC cases comprising 20 bronchial (10 in-situ, 10 advanced) and 22 laryngeal (12 in-situ, 10 advanced), and 13 controls. There were 32 (76%) male SCC cases with mean age 63.6 (SD = 9.5) compared with 11 (85%) male controls with mean age 61.9 (SD = 10.1). Predictive models for in situ cases had good sensitivity and specificity compared to controls (overall, 95% and 69%; laryngeal, 100% and 85%; bronchial, 77% and 80%). When distinguishing in-situ and advanced tumours, sensitivity and specificity 82% and 75% respectively. For different tumour types (bronchial versus advanced laryngeal) sensitivity and specificity were 100% and 80% respectively. VOCs isolated from in-situ cancers included some previously demonstrated in advanced cancers and some novel VOCs. In-situ bronchial and laryngeal cancer can be detected by VOC analysis. Distinction from normal controls and between the two tumour types could allow screening in high risk groups for these curable lesions.


Assuntos
Testes Respiratórios/métodos , Neoplasias Brônquicas/diagnóstico , Carcinoma in Situ/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Laríngeas/diagnóstico , Compostos Orgânicos Voláteis/análise , Brônquios/patologia , Broncoscopia , Estudos de Casos e Controles , Feminino , Fluorescência , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Laringe/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
4.
J Breath Res ; 14(4): 047105, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33021205

RESUMO

The influence of breath sampling on exhaled carbon monoxide (eCO) and related pulmonary gas exchange parameters is investigated in a study with 32 healthy non-smokers. Mid-infrared tunable diode laser absorption spectroscopy and well-controlled online sampling is used to precisely measure mouth- and nose-exhaled CO expirograms at exhalation flow rates (EFRs) of 250, 120 and 60 ml s-1, and for 10 s of breath-holding followed by exhalation at 120 ml s-1. A trumpet model with axial diffusion is employed to fit simulated exhalation profiles to the experimental expirograms, which provides equilibrium airway and alveolar CO concentrations and the average lung diffusing capacity in addition to end-tidal concentrations. For all breathing maneuvers, excellent agreement is found between mouth- and nose-exhaled end-tidal CO (ETCO), and the individual values for ETCO and alveolar diffusing capacity are consistent across maneuvers. The eCO parameters clearly show a dependence on EFR, where the lung diffusing capacity increases with EFR, while ETCO slightly decreases. End-tidal CO is largely independent of ambient air CO and alveolar diffusing capacity. While airway CO is slightly higher than, and correlates strongly with, ambient air CO, and there is a weak correlation with ETCO, the results point to negligible endogenous airway CO production in healthy subjects. An EFR of around 120 ml s-1 can be recommended for clinical eCO measurements. The employed method provides means to measure variations in endogenous CO, which can improve the interpretation of exhaled CO concentrations and the diagnostic value of eCO tests in clinical studies. Clinical trial registration number: 2017/306-31.


Assuntos
Testes Respiratórios/métodos , Monóxido de Carbono/análise , Expiração , Manejo de Espécimes , Adulto , Feminino , Heme/metabolismo , Humanos , Masculino , Boca , Nariz , Reologia
5.
J Breath Res ; 14(4): 046012, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33021213

RESUMO

Breath analysis holds promise for non-invasive in vivo monitoring of disease related processes. However, physiological parameters may considerably affect profiles of exhaled volatile organic substances (VOCs). Volatile substances can be released via alveoli, bronchial mucosa or from the upper airways. The aim of this study was the systematic investigation of the influence of different sampling sites in the respiratory tract on VOC concentration profiles by means of a novel experimental setup. After ethical approval, breath samples were collected from 25 patients undergoing bronchoscopy for endobronchial ultrasound or bronchoscopic lung volume reduction from different sites in the airways. All patients had total intravenous anaesthesia under pressure-controlled ventilation. If necessary, respiratory parameters were adjusted to keep PETCO2 = 35-45 mm Hg. 30 ml gas were withdrawn at six sampling sites by means of gastight glass syringes: S1 = Room air, S2 = Inspiration, S3 = Endotracheal tube, S4 = Trachea, S5 = Right B6 segment, S6 = Left B6 segment (S4-S6 through the bronchoscope channel). 10 ml were used for VOC analysis, 20 ml for PCO2 determination. Samples were preconcentrated by solid-phase micro-extraction (SPME) and analysed by gas chromatography-mass spectrometry (GC-MS). PCO2 was determined in a conventional blood gas analyser. Statistically significant differences in substance concentrations for acetone, isoprene, 2-methyl-pentane and n-hexane could be observed between different sampling sites. Increasing substance concentrations were determined for acetone (15.3%), 2-methyl-pentane (11.4%) and n-hexane (19.3%) when passing from distal to proximal sampling sites. In contrast, isoprene concentrations decreased by 9.9% from proximal to more distal sampling sites. Blank bronchoscope measurements did not show any contaminations. Increased substance concentrations in the proximal respiratory tract may be explained through substance excretion from bronchial mucosa while decreased concentrations could result from absorption or reaction processes. Spatial mapping of VOC profiles can provide novel insights into substance specific exhalation kinetics and mechanisms.


Assuntos
Testes Respiratórios/métodos , Broncoscopia , Expiração , Manejo de Espécimes , Compostos Orgânicos Voláteis/análise , Dióxido de Carbono/química , Feminino , Humanos , Limite de Detecção , Pulmão/química , Masculino , Pessoa de Meia-Idade , Pressão Parcial
6.
Sci Rep ; 10(1): 16159, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999424

RESUMO

Chronic inflammatory lung diseases impact more than 300 million of people worldwide. Because they are not curable, these diseases have a high impact on both the quality of life of patients and the healthcare budget. The stability of patient condition relies mostly on constant treatment adaptation and lung function monitoring. However, due to the variety of inflammation phenotypes, almost one third of the patients receive an ineffective treatment. To improve phenotyping, we evaluated the complementarity of two techniques for exhaled breath analysis: full resolving comprehensive two-dimensional gas chromatography coupled to high-resolution time-of-flight mass spectrometry (GC × GC-HRTOFMS) and rapid screening selected ion flow tube MS (SIFT-MS). GC × GC-HRTOFMS has a high resolving power and offers a full overview of sample composition, providing deep insights on the ongoing biology. SIFT-MS is usually used for targeted analyses, allowing rapid classification of samples in defined groups. In this study, we used SIFT-MS in a possible untargeted full-scan mode, where it provides pattern-based classification capacity. We analyzed the exhaled breath of 50 asthmatic patients. Both techniques provided good classification accuracy (around 75%), similar to the efficiency of other clinical tools routinely used for asthma phenotyping. Moreover, our study provides useful information regarding the complementarity of the two techniques.


Assuntos
Asma/metabolismo , Testes Respiratórios/métodos , Expiração , Inflamação/metabolismo , Fenótipo , Adulto , Idoso , Eosinófilos/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Escarro/metabolismo
7.
PLoS One ; 15(10): e0241079, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33096546

RESUMO

PURPOSE: To evaluate the intra-unit (RELINTRA) and inter-unit reliability (RELINTER) of two structurally identical units of the metabolic analyser K5 (COSMED, Rome, Italy) that allows to utilize either breath-by-breath (BBB) or dynamic mixing chamber (DMC) technology. METHODS: Identical flow- and gas-signals were transmitted to both K5s that always operated simultaneously either in BBB- or DMC-mode. To assess RELINTRA and RELINTER, a metabolic simulator was applied to simulate four graded levels of respiration. RELINTRA and RELINTER were expressed as typical error (TE%) and Intraclass Correlation Coefficient (ICC). To assess also inter-unit differences via natural respiratory signals, 12 male athletes performed one incremental bike step test each in BBB- and DMC-mode. Inter-unit differences within biological testing were expressed as percentages. RESULTS: In BBB, TE% of RELINTRA ranged 0.30-0.67 vs. RELINTER 0.16-1.39 and ICC ranged 0.57-1.00 vs. 0.09-1.00. In DMC, TE% of RELINTRA ranged 0.38-0.90 vs. RELINTER 0.03-0.86 and ICC ranged 0.22-1.00 vs. 0.52-1.00. Mean inter-unit differences ranged -2.30-2.20% (Cohen's ds (ds) 0.13-1.52) for BBB- and -0.55-0.61% (ds 0.00-0.65) for DMC-mode, respectively. Inter-unit differences for [Formula: see text] and RER were significant (p < 0.05) at each step. CONCLUSION: Two structurally identical K5-units demonstrated accurate RELINTRA with TE < 2.0% and similar RELINTER during metabolic simulation. During biological testing, inter-unit differences for [Formula: see text] and RER in BBB-mode were higher than 2% with partially large ES in BBB. Hence, the K5 should be allocated personally wherever possible. Otherwise, e.g. in multicenter studies, a decrease in total reliability needs to be considered especially when the BBB-mode is applied.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Teste de Esforço/normas , Adulto , Atletas , Testes Respiratórios/métodos , Teste de Esforço/métodos , Teste de Esforço/estatística & dados numéricos , Humanos , Estudos Longitudinais , Masculino , Estudos Multicêntricos como Assunto , Variações Dependentes do Observador , Guias de Prática Clínica como Assunto , Reprodutibilidade dos Testes , Respiração
8.
Am J Physiol Heart Circ Physiol ; 319(5): H1078-H1086, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32946269

RESUMO

Mixed venous oxygen (O2) saturation ([Formula: see text]) is an important measure for evaluating the sufficiency of cardiac output (CO) relative to whole body O2 consumption (V̇o2), while clinical use is limited to the required invasive catheterization. According to Fick's equation, V̇o2 (mL/min) = CO (L/min) × Hb (g/dL) × 1.36 (mL/g) × ([Formula: see text] - [Formula: see text])/10 (Hb = hemoglobin concentration, [Formula: see text] = arterial blood O2 saturation). Because V̇o2, CO, Hb, and [Formula: see text] can be measured noninvasively with expired gas analysis, echocardiography, a simple blood test, and percutaneous O2 saturation, respectively, [Formula: see text] can be calculated noninvasively. We hypothesized that noninvasively calculated [Formula: see text] shows a significant correlation and agrees well with invasively measured [Formula: see text]. In 47 patients (29 men; mean age, 70 ± 12 yr) who underwent right heart catheterization, [Formula: see text] was directly measured by sampling pulmonary artery blood. Noninvasively calculated [Formula: see text] was also obtained by the method described above. The calculated [Formula: see text] was significantly correlated with the measured [Formula: see text] (r = 0.79, P < 0.001) and was significantly smaller than the measured [Formula: see text] (70 ± 5.1 vs. 72.1 ± 4.9%, P < 0.001). Bias at [Formula: see text] was -2.2% (95% confidence interval, -3.2 to -1.1%) with limits of agreement from -9.5 to 5.2%, demonstrating acceptable agreement. The optimal cutoff value of calculated [Formula: see text] was 69% for reduced measured [Formula: see text] < 70% with an area under the curve of 0.94. Reduced calculated [Formula: see text] < 69% indicated a sensitivity of 92.9% and a specificity of 90.9% for reduced measured [Formula: see text] < 70%. Noninvasive [Formula: see text] calculated from echocardiography, expired gas analysis, percutaneous arterial blood O2 saturation, and hemoglobin level significantly correlated and agreed well with direct [Formula: see text] measured by catheterization. This novel method allows for practical evaluation of [Formula: see text] to assess the sufficiency of CO according to whole body metabolism.NEW & NOTEWORTHY Clinical use of mixed venous oxygen saturation ([Formula: see text]) is limited to the required invasive procedure. With Fick's equation, expired gas analysis, echocardiography, simple blood tests, and percutaneous oxygen saturation, [Formula: see text] can be calculated noninvasively. We hypothesized that noninvasively calculated [Formula: see text] shows a significant correlation and agrees well with invasively measured [Formula: see text]. The present study examined the relationship between measured [Formula: see text] and calculated [Formula: see text] in patients who underwent right heart catheterization and demonstrated acceptable agreement. This novel method can expand the indication of evaluating [Formula: see text].


Assuntos
Ecocardiografia/métodos , Expiração , Oximetria/métodos , Consumo de Oxigênio , Oxigênio/sangue , Veias/fisiologia , Idoso , Idoso de 80 Anos ou mais , Testes Respiratórios/métodos , Débito Cardíaco , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Clinics (Sao Paulo) ; 75: e1764, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935823

RESUMO

OBJECTIVES: This study aimed to determine the accuracy of the Breath-Alert™ portable breath meter (BA) for the detection of halitosis in children and adolescents, considering the organoleptic test (OT) as the gold standard in this assessment. METHODS: A cross-sectional study was conducted on 150 children (aged 6-12 years). OT was performed by three independent examiners on a single occasion, obtaining three scores of 0-5 points on the Rosenberg's organoleptic scale. The median of the three evaluations for each child was used for analysis. BA was used according to the manufacturer's instructions, with breath odor scored from 0-5 points. Scores ≥2 on both tests were considered indicative of halitosis. RESULTS: A total of 26 (17.3%) and 23 (15.3%) children were detected with halitosis on the OT and BA tests, respectively. The sensitivity and specificity of the BA scores for the detection of halitosis were 80.76% and 98.38%, respectively. The positive and negative predictive values for BA were 91.3% and 96.06%, respectively. CONCLUSION: In the present study involving children, who require fast, practical examinations, BA proved to be an auxiliary tool to OT for the detection of halitosis in the practice of pediatric dentistry, demonstrating high sensitivity and specificity.


Assuntos
Testes Respiratórios/métodos , Halitose/diagnóstico , Adolescente , Testes Respiratórios/instrumentação , Criança , Estudos Transversais , Feminino , Halitose/metabolismo , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Compostos de Enxofre/análise
10.
J Breath Res ; 14(4): 043001, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32969348

RESUMO

Cavity-enhanced absorption spectroscopies (CEAS) have gained importance in a wide range of applications in molecular spectroscopy. The development of optical sensors based on the CEAS techniques coupled with the continuous wave or pulsed laser sources operating in the mid-infrared or near-infrared spectral regime uniquely offers molecularly selective and ultra-sensitive detection of trace species in complex matrices including exhaled human breath. In this review, we discussed recent applications of CEAS for analyzing trace constituents within the exhaled breath matrix facilitating the non-invasive assessment of human health status. Next to a brief discussion on the mechanisms of formation of trace components found in the exhaled breath matrix related to particular disease states, existing challenges in CEAS and future development towards non-invasive clinical diagnostics will be discussed.


Assuntos
Testes Respiratórios/métodos , Expiração , Óptica e Fotônica/métodos , Animais , Humanos , Óxido Nítrico/análise , Consumo de Oxigênio , Espectroscopia de Luz Próxima ao Infravermelho
11.
J Breath Res ; 14(4): 046010, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32969351

RESUMO

Inhalation of smoke is shown to be associated with adverse respiratory outcomes in firefighters. Due to invasiveness of procedures to obtain airways lining fluid, the immediate responses of the target organ (i.e. lung) are secondarily assessed through biomarkers in blood and urine. The objective of this study was to identify changes in metabolic profile of exhaled breath condensate (EBC) and lung function of firefighters exposed to wildfires smoke. A total of 29 subjects were studied over 16 events; 14 of these subjects provided cross-shift EBC samples. The predominant types of non-exchangeable hydrogen in EBC were saturated oxygenated hydrogen, aliphatic alkyl and allylic. Non-exchangeable allylic and oxygenated hydrogen concentrations decreased in post-exposure EBC samples. Longer exposures were correlated with increased abundance of oxidized carbon in ketones, acids and esters. Post-exposure lung function declines (forced expiratory volume in 1 s (FEV1): 0.08 l, forced vital capacity (FVC): 0.07 l, FEV1/FVC: 0.03 l, peak expiratory flow (PEF): 0.39 l s-1) indicated airways inflammation. They were related to exposure intensity (FEV1 and FVC) and exposure duration (PEF). This study showed that EBC characterization of non-exchangeable hydrogen types by NMR may provide insights on EBC molecular compositions in response to smoke inhalation and facilitate targeted analysis to identify specific biomarkers.


Assuntos
Testes Respiratórios/métodos , Expiração , Bombeiros , Hidrogênio/análise , Pulmão/fisiologia , Testes de Função Respiratória , Incêndios Florestais , Adulto , Biomarcadores/análise , Biomassa , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Espectroscopia de Prótons por Ressonância Magnética , Capacidade Vital
12.
Sci Rep ; 10(1): 15403, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958842

RESUMO

The eradication rate of Helicobacter pylori (H. pylori) has been decreasing every year, mainly due to the increase in antibiotic resistance. In fact, many other factors may affect H. pylori eradication. To analyze the clinical factors affecting the initial eradication therapy in Chinese patients with H. pylori infection. We conducted a retrospective study on 264 outpatients who were diagnosed with H. pylori-associated chronic gastritis and peptic ulcer disease between January and December 2015 at a large tertiary hospital in China. The patients were divided into three groups: ECA, RCA, and RCM (R: 20 mg rabeprazole, E: 40 mg esomeprazole, C: 0.5 g clarithromycin, A: 1.0 g amoxicillin and M: 0.4 g metronidazole). The patients were treated for 14 days and followed up for 1 year. The 14C-urea breath test (14C-UBT) was performed 4 weeks after the completion of the eradication therapy. The eradication rate was higher in ≥ 40-year-old patients than in < 40-year-old-patients (85.7% vs. 54.7%, p = 0.002). Multivariate analyses revealed only age ≥ 40 years to be significantly associated with a high H. pylori eradication rate [odds ratio (OR) 4.58, p = 0.003]. The H. pylori eradication rate in patients with duodenal ulcers was significantly higher than that in patients with gastric ulcers (79% vs. 60%, p = 0.012). Age could be a predictor of successful H. pylori eradication. Patients with duodenal ulcers had a higher H. pylori eradication rate than those with other lesions.


Assuntos
Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/terapia , Helicobacter pylori/efeitos dos fármacos , Adulto , Idoso , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Antiulcerosos/uso terapêutico , Testes Respiratórios/métodos , Claritromicina/uso terapêutico , Esquema de Medicação , Quimioterapia Combinada , Esomeprazol/uso terapêutico , Feminino , Gastrite/tratamento farmacológico , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/patogenicidade , Helicobacter pylori/virologia , Humanos , Masculino , Metronidazol/uso terapêutico , Pessoa de Meia-Idade , Úlcera Péptica/tratamento farmacológico , Inibidores da Bomba de Prótons/uso terapêutico , Rabeprazol/uso terapêutico , Estudos Retrospectivos
13.
Sci Rep ; 10(1): 14109, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32839494

RESUMO

Control of breathing is automatic and its regulation is keen to autonomic functions. Therefore, involuntary and voluntary nervous regulation of breathing affects ventilatory variations, which has profound potential to address expanding challenges in contemporary pulmonology. Nonetheless, the fundamental attributes of the aforementioned phenomena are rarely understood and/or investigated. Implementation of unconventional approach like breathomics may leads to a better comprehension of those complexities in respiratory medicine. We applied breath-resolved spirometry and capnometry, non-invasive hemodynamic monitoring along with continuous trace analysis of exhaled VOCs (volatile organic compounds) by means of real-time mass-spectrometry in 25 young and healthy adult humans to investigate any possible mirroring of instant ventilatory variations by exhaled breath composition, under varying respiratory rhythms. Hemodynamics remained unaffected. Immediate changes in measured breath compositions and corresponding variations occurred when respiratory rhythms were switched between spontaneous (involuntary/unsynchronised) and/or paced (voluntary/synchronised) breathing. Such changes in most abundant, endogenous and bloodborne VOCs were closely related to the minute ventilation and end-tidal CO2 exhalation. Unprecedentedly, while preceded by a paced rhythm, spontaneous rhythms in both independent setups became reproducible with significantly (P-value ≤ 0.005) low intra- and inter-individual variation in measured parameters. We modelled breath-resolved ventilatory variations via alveolar isoprene exhalation, which were independently validated with unequivocal precision. Reproducibility i.e. attained via our method would be reliable for human breath sampling, concerning biomarker research. Thus, we may realize the actual metabolic and pathophysiological expressions beyond the everlasting in vivo physiological noise. Consequently, less pronounced changes are often misinterpreted as disease biomarker in cross-sectional studies. We have also provided novel information beyond conventional spirometry and capnometry. Upon clinical translations, our findings will have immense impact on pulmonology and breathomics as they have revealed a reproducible pattern of ventilatory variations and respiratory homeostasis in endogenous VOC exhalations.


Assuntos
Testes Respiratórios/métodos , Dióxido de Carbono/análise , Expiração/fisiologia , Respiração , Compostos Orgânicos Voláteis/análise , Adulto , Monitorização Transcutânea dos Gases Sanguíneos/métodos , Feminino , Hemodinâmica/fisiologia , Humanos , Inalação/fisiologia , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Pneumologia , Espirometria/métodos , Adulto Jovem
15.
ACS Nano ; 14(9): 12125-12132, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32808759

RESUMO

This article reports on a noninvasive approach in detecting and following-up individuals who are at-risk or have an existing COVID-19 infection, with a potential ability to serve as an epidemic control tool. The proposed method uses a developed breath device composed of a nanomaterial-based hybrid sensor array with multiplexed detection capabilities that can detect disease-specific biomarkers from exhaled breath, thus enabling rapid and accurate diagnosis. An exploratory clinical study with this approach was examined in Wuhan, China, during March 2020. The study cohort included 49 confirmed COVID-19 patients, 58 healthy controls, and 33 non-COVID lung infection controls. When applicable, positive COVID-19 patients were sampled twice: during the active disease and after recovery. Discriminant analysis of the obtained signals from the nanomaterial-based sensors achieved very good test discriminations between the different groups. The training and test set data exhibited respectively 94% and 76% accuracy in differentiating patients from controls as well as 90% and 95% accuracy in differentiating between patients with COVID-19 and patients with other lung infections. While further validation studies are needed, the results may serve as a base for technology that would lead to a reduction in the number of unneeded confirmatory tests and lower the burden on hospitals, while allowing individuals a screening solution that can be performed in PoC facilities. The proposed method can be considered as a platform that could be applied for any other disease infection with proper modifications to the artificial intelligence and would therefore be available to serve as a diagnostic tool in case of a new disease outbreak.


Assuntos
Testes Respiratórios/instrumentação , Infecções por Coronavirus/diagnóstico , Nanoestruturas , Pneumonia Viral/diagnóstico , Grupo com Ancestrais do Continente Asiático , Betacoronavirus , Biomarcadores/análise , Testes Respiratórios/métodos , China , Confiabilidade dos Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Sistema Respiratório , Sensibilidade e Especificidade
16.
J Stud Alcohol Drugs ; 81(4): 505-510, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32800088

RESUMO

OBJECTIVE: Sensing the effects of alcohol consumption in real time could offer numerous opportunities to reduce related harms. This study sought to explore accuracy of gait-related features measured by smartphone accelerometer sensors on detecting alcohol intoxication (breath alcohol concentration [BrAC] > .08%). METHOD: In a controlled laboratory study, participants (N = 17; 12 male) were asked to walk 10 steps in a straight line, turn, and walk 10 steps back before drinking and each hour, for up to 7 hours after drinking a weight-based dose of alcohol to reach a BrAC of .20%. Smartphones were placed on the lumbar region and 3-axis accelerometer data was recorded at a rate of 100 Hz. Accelerometer data were segmented into task segments (i.e., walk forward, walk backward). Features were generated for each overlapping 1-second windows, and the data set was split into training and testing data sets. Logistic regression models were used to estimate accuracy for classifying BrAC ≤ .08% from BrAC > .08% for each subject. RESULTS: Across participants, BrAC > .08% was predicted with a mean accuracy of 92.5% using logistic regression, an improvement from a naive model accuracy of 88.2% (mean sensitivity = .89; specificity = .92; positive predictive value = .77; and negative predictive value = .97). The two most informative accelerometer features were mean signal amplitude and variance of the signal in the x-axis (i.e., gait sway). CONCLUSIONS: We found preliminary evidence supporting use of gait-related features measured by smartphone accelerometer sensors to detect alcohol intoxication. Future research should determine whether these findings replicate in situ.


Assuntos
Acelerometria/métodos , Intoxicação Alcoólica/diagnóstico , Testes Respiratórios/métodos , Marcha , Smartphone , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
17.
J Breath Res ; 14(4): 046009, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32698165

RESUMO

The objective of the present study was to identify volatile prints from exhaled breath, termed breath-print, from breast cancer (BC) patients and healthy women by means of an electronic nose and to evaluate its potential use as a screening method. A cross-sectional study was performed on 443 exhaled breath samples from women, of whom 262 had been diagnosed with BC by biopsy and 181 were healthy women (control group). Breath-print analysis was performed utilizing the Cyranose 320 electronic nose. Group data were evaluated by principal component analysis (PCA), canonical discriminant analysis (CDA), and support vector machine (SVM), and the test's diagnostic power was evaluated by means of receiver operating characteristic (ROC) curves. The results obtained using the model generated from the CDA, which best describes the behavior of the assessed groups, indicated that the breath-print of BC patients was different from that of healthy women and that they presented with a variability of up to 98.8% and a correct classification of 98%. The sensitivity, specificity, negative predictive value, and positive predictive value reached 100% according to the ROC curve. The present study demonstrates the capability of the electronic nose to separate between healthy subjects and BC patients. This research could have a beneficial impact on clinical practice as we consider that this test could probably be used at the first point before the application of established gold tests (mammography, ultrasound, and biopsy) and substantially improve screening tests in the general population.


Assuntos
Neoplasias da Mama/diagnóstico , Testes Respiratórios/métodos , Nariz Eletrônico , Expiração , Compostos Orgânicos Voláteis/análise , Adulto , Estudos de Casos e Controles , Estudos Transversais , Análise Discriminante , Feminino , Humanos , Pessoa de Meia-Idade , Análise de Componente Principal , Curva ROC , Reprodutibilidade dos Testes
18.
Chest ; 158(6): 2502-2510, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32652095

RESUMO

To reduce the spread of the severe acute respiratory syndrome coronavirus 2, many pulmonary function testing (PFT) laboratories have been closed or have significantly reduced their testing capacity. Because these mitigation strategies may be necessary for the next 6 to 18 months to prevent recurrent peaks in disease prevalence, fewer objective measurements of lung function will alter the diagnosis and care of patients with chronic respiratory diseases. PFT, which includes spirometry, lung volume, and diffusion capacity measurement, is essential to the diagnosis and management of patients with asthma, COPD, and other chronic lung conditions. Both traditional and innovative alternatives to conventional testing must now be explored. These may include peak expiratory flow devices, electronic portable spirometers, portable exhaled nitric oxide measurement, airwave oscillometry devices, and novel digital health tools such as smartphone microphone spirometers and mobile health technologies along with integration of machine learning approaches. The adoption of some novel approaches may not merely replace but could improve existing management strategies and alter common diagnostic paradigms. With these options comes important technical, privacy, ethical, financial, and medicolegal barriers that must be addressed. However, the coronavirus disease 19 pandemic also presents a unique opportunity to augment conventional testing by including innovative and emerging approaches to measuring lung function remotely in patients with respiratory disease. The benefits of such an approach have the potential to enhance respiratory care and empower patient self-management well beyond the current global pandemic.


Assuntos
Assistência à Saúde/métodos , Pneumopatias/diagnóstico , Pneumopatias/terapia , Testes de Função Respiratória/instrumentação , Testes de Função Respiratória/métodos , Asma/diagnóstico , Asma/fisiopatologia , Asma/terapia , Testes Respiratórios/instrumentação , Testes Respiratórios/métodos , Doença Crônica , Fibrose Cística/diagnóstico , Fibrose Cística/terapia , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/terapia , Invenções , Pneumopatias/fisiopatologia , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/terapia , Medidas de Volume Pulmonar , Aprendizado de Máquina , Oscilometria/instrumentação , Oscilometria/métodos , Pico do Fluxo Expiratório , Capacidade de Difusão Pulmonar/instrumentação , Capacidade de Difusão Pulmonar/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/terapia , Autogestão , Smartphone , Espirometria/instrumentação , Espirometria/métodos
19.
J Breath Res ; 14(3): 030202, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32662449

RESUMO

November 2019 saw Cambridge, UK play host to the second Breath Biopsy Conference, a community-focused event aimed at sharing and supporting advancements in the collection and analysis of volatile organic compounds in exhaled breath. The event expanded upon the previous year's format, spanning two days and concluding with an expert panel discussion. Presentations covered detection, monitoring and precision medicine studies examining diseases including asthma, cirrhosis, cancer and tuberculosis. The meeting attracted representatives from diverse backgrounds, such as metabolomics, artificial intelligence, clinical research and chemical analysis. This meeting report offers an overview of what was presented and discussed during the conference.


Assuntos
Biomarcadores/análise , Testes Respiratórios/métodos , Expiração , Inteligência Artificial , Biópsia , Humanos , Compostos Orgânicos Voláteis/análise
20.
J Breath Res ; 14(4): 046008, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32604084

RESUMO

Sampling of volatile organic compounds (VOCs) has shown promise for detection of a range of diseases but results have proved hard to replicate due to a lack of standardization. In this work we introduce the 'Peppermint Initiative'. The initiative seeks to disseminate a standardized experiment that allows comparison of breath sampling and data analysis methods. Further, it seeks to share a set of benchmark values for the measurement of VOCs in breath. Pilot data are presented to illustrate the standardized approach to the interpretation of results obtained from the Peppermint experiment. This pilot study was conducted to determine the washout profile of peppermint compounds in breath, identify appropriate sampling time points, and formalise the data analysis. Five and ten participants were recruited to undertake a standardized intervention by ingesting a peppermint oil capsule that engenders a predictable and controlled change in the VOC profile in exhaled breath. After collecting a pre-ingestion breath sample, five further samples are taken at 2, 4, 6, 8, and 10 h after ingestion. Samples were analysed using ion mobility spectrometry coupled to multi-capillary column and thermal desorption gas chromatography mass spectrometry. A regression analysis of the washout data was used to determine sampling times for the final peppermint protocol, and the time for the compound measurement to return to baseline levels was selected as a benchmark value. A measure of the quality of the data generated from a given technique is proposed by comparing data fidelity. This study protocol has been used for all subsequent measurements by the Peppermint Consortium (16 partners from seven countries). So far 1200 breath samples from 200 participants using a range of sampling and analytical techniques have been collected. The data from the consortium will be disseminated in subsequent technical notes focussing on results from individual platforms.


Assuntos
Testes Respiratórios/métodos , Mentha piperita/química , Compostos Orgânicos Voláteis/química , Benchmarking , Feminino , Humanos , Masculino
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