Journal of breath research最新文献

{"title":"Wearable Sensors and VOC Monitoring: Data Fusion and Machine Learning for Non-Invasive Disease Detection.","authors":"Reid Honeycutt, Flore M Hervé, Patrick Gibson, Eva Borras, Dante E Rojas, Yevgeniy Belous, Stephanie Fung, Mitchell M McCartney, Nicholas J Kenyon, Cristina E Davis","doi":"10.1088/1752-7163/aeb685","DOIUrl":"https://doi.org/10.1088/1752-7163/aeb685","url":null,"abstract":"<p><p>Emerging technologies that detect volatile organic compounds (VOCs) emanating from the body enable rapid and non-invasive detection of diseases. Respiratory illnesses, in particular, can be identified through measurement of VOCs in exhaled breath. However, the low specificity of some methods leaves room for improvement. By combining information from multiple data streams, we can potentially improve on the results obtained from using each data stream individually. Here we evaluate a novel data fusion approach combining a wearable vitals monitor and exhaled breath VOCs for the classification of asthma patients. The wearable vitals monitor or \"e-glove\" measures key information such as skin temperature, trans-epidermal water loss (TEWL), heart rate, and galvanic skin response (GSR), while the breath VOC data (measured by gold standard gas chromatography-mass spectrometry, GC-MS) provide insight into the biochemical and metabolic state of the body. Data fusion is a process used in many applications for combining information from disparate sources. We leverage data fusion in this case to achieve superior classification accuracy using the integrated data streams. The low-level data fusion achieved a higher ROC AUC score (0.88) in asthma classification than the breath VOC-only approach (0.72, p<0.001). These results are promising for the future data analysis workflows for non-invasive diagnostic and health monitoring.</p>","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149228036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overnight changes in exhaled carbon dioxide, oxygen, and nitrous oxide in obstructive sleep apnea: associations with disease severity and polysomnographic findings.","authors":"Mustafa Buğra Buğra Coşkuner, Buğra Kerget, Esra Sönmez, Huseyin Erdal, İsmail Bayraklı","doi":"10.1088/1752-7163/aeb686","DOIUrl":"https://doi.org/10.1088/1752-7163/aeb686","url":null,"abstract":"<p><strong>Background: </strong>Exhaled breath analysis is a non-invasive approach for assessing physiological alterations in obstructive sleep apnea (OSA). This study evaluated overnight changes in exhaled CO₂, O₂, and N₂O concentrations and their associations with OSA severity and polysomnographic parameters.&#xD;Methods: In this prospective observational study, 62 adults undergoing diagnostic overnight polysomnography were enrolled and classified as having no OSA (n = 21), mild-to-moderate OSA (n = 21), or severe OSA (n = 20) according to the apnea-hypopnea index. Exhaled CO₂, O₂, and N₂O concentrations were measured immediately before and after overnight polysomnography under standardized conditions.&#xD;Results: Morning exhaled N₂O concentrations were significantly higher in patients with severe OSA than in the other groups (p = 0.001). Overnight changes in exhaled CO₂ (ΔCO₂), N₂O (ΔN₂O), and O₂ (ΔO₂) differed significantly according to OSA severity (all p < 0.001). Compared with the no OSA group, patients with OSA exhibited greater overnight increases in exhaled CO₂ and N₂O concentrations together with greater decreases in exhaled O₂ concentrations. Overnight ΔN₂O and ΔO₂ showed strong correlations with AHI (ρ = -0.760 and 0.912, respectively; both p < 0.001) and ODI (ρ = -0.713 and 0.913, respectively; both p < 0.001).&#xD;Conclusion: Patients with OSA exhibited more pronounced overnight alterations in exhaled gas composition, particularly greater changes in exhaled O₂ and N₂O concentrations. These findings suggest that dynamic overnight exhaled gas changes may reflect physiological alterations associated with OSA severity and warrant further validation in larger prospective studies.&#xD.</p>","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149227985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Breath acetone changes in decompensated heart failure patients on inotropes.","authors":"Daniella Motta da Costa Dan, Fernando Bacal, Diogenes Furlan, Camila Lira, Rafael Rinco, Sandrigo Mangini, Beatriz Guilherme, Giovanna Magalhães, Tatiana Leal, Alexandre Soeiro, Monica Avila, Iascara Wozniak de Campos, Luis Fernando Bernal Seguro, Bruno Biselli, Edimar Bocchi, Múcio Tavares Oliveira-Junior, Ivano Gutz, Fabiana G Marcondes-Braga","doi":"10.1088/1752-7163/aeab05","DOIUrl":"10.1088/1752-7163/aeab05","url":null,"abstract":"<p><p>Early assessment of treatment response in patients with decompensated heart failure (HF) requiring inotropic support remains challenging. Exhaled breath acetone, a noninvasive marker of ketone body metabolism, may reflect dynamic metabolic changes associated with clinical status. We aimed to evaluate short-term temporal changes in exhaled breath acetone levels following inotropic therapy in patients with decompensated HF. This is a prospective, single-center observational study including patients with HF requiring inotropic therapy. Exhaled breath acetone levels were measured in decompensated HF patients requiring inotropic support using a previously described noninvasive device at hospital admission and within 48 h. The analysis was performed by spectrophotometry after reaction with salicylaldehyde. Ninety-seven patients were enrolled. Baseline median exhaled breath acetone concentration at admission was 7.75 (3.90-12.27)<i>µ</i>g l^-1and decreased to 2.15 (1.10-4.19)<i>µ</i>g l^-1after 48 h of inotrope initiation (<i>p</i>< 0.001 for within-patient comparison). This reduction was accompanied by clinical improvement in signs of HF decompensation and occurred in patients with or without type 2 diabetes, although the magnitude of this reduction was greater in patients without diabetes (<i>p</i>= 0.001). Elevated exhaled breath acetone levels were observed in patients with decompensated HF and decreased after initiation of inotropic therapy, paralleling clinical improvement. These findings are hypothesis-generating and larger prospective studies may confirm the potential role of exhaled breath acetone in clinical decision-making.</p>","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149025049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Amino acid profiles in exhaled breath condensate: evaluation of collection methods and diurnal variation using LC-MS/MS.","authors":"Soo Takasu, Momoka Ishizuka, Hiroya Murakami, Norio Teshima, Yukihiro Esaka","doi":"10.1088/1752-7163/aead13","DOIUrl":"10.1088/1752-7163/aead13","url":null,"abstract":"<p><p>Exhaled breath condensate (EBC) is a non-invasive biological fluid that reflects metabolic activity in the respiratory tract. It has attracted interest as a potential source of biomarkers for respiratory diseases. EBC contains amino acids that play central roles in metabolism and disease pathophysiology; these amino acids may therefore serve as promising biomarkers. However, the analysis of these amino acids remains limited because of their low concentrations, and their diurnal variation remains unclear. Furthermore, variability in collection devices and the risk of saliva contamination can make the reliable analysis of amino acids in EBC difficult. In this study, we developed a sensitive and robust method for analyzing amino acids in EBC using hydrophilic interaction chromatography coupled with mass spectrometry. Adding succinic acid to the mobile phase increased ionization efficiency. In post-column mixing experiments, addition of succinic acid improved peak areas, with more than three-fold increases observed for 10 of 16 amino acids. We conducted preliminary human studies to evaluate the effects of collection devices, saliva contamination, and diurnal variation. Both syringe-based and commercial RTube devices enabled EBC collection in a small sample size (); however, the RTube yielded larger sample volumes. Despite differences in EBC yield, amino-acid concentrations showed largely similar trends between the two devices in most participants, although sample-specific variation was observed. Diurnal variation in healthy subjects () revealed peak amino-acid levels after overnight fasting, followed by a secondary rise after lunch. Differences in amino-acid composition ratios between individuals were less pronounced than differences in absolute concentrations. This study demonstrates a practical method for quantifying amino acids in EBC and highlights the impact of technical and biological factors on measured levels. These preliminary findings support further evaluation of EBC amino-acid profiles as potential biomarkers for respiratory diseases.</p>","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149074935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metabolic alterations in pneumonia assessed by breath analysis: an exploratory paired longitudinal study comparing acute infection and post-recovery states.","authors":"Britta C Brugger, Noriane A Sievi, Sarah Basler, Patrick Baumgartner, Jonas Herth, Felix Schmidt, Kapil Dev Singh, Pablo Sinues, Malcolm Kohler","doi":"10.1088/1752-7163/aead14","DOIUrl":"10.1088/1752-7163/aead14","url":null,"abstract":"<p><p>The diagnosis and monitoring of pneumonia remain a challenge due to its diverse etiology, overlapping clinical symptoms with other respiratory infections, and limitations in current diagnostic technologies for timely and accurate detection. We evaluated whether real-time secondary electrospray ionization-high-resolution mass spectrometry breathomics can capture pneumonia-associated breath-profile changes in a paired longitudinal cohort. In this single-center longitudinal study at University Hospital Zurich, Switzerland, adults with clinically confirmed pneumonia (<i>n</i>= 47, median age: 63) were enrolled between 2020 and 2023 sampled during acute infection and again after recovery (median interval 85 d). After pre-processing, 3635 mass-spectral features were retained across ion modes, and 1498 could be linked to at least one human metabolome database (HMDB) entry by accurate-mass matching (±1 ppm). Breath profiles were assessed using a subject-grouped, nested cross-validated partial least squares discriminate analysis (PLS-DA) and paired differential analysis. PLS-DA showed framework moderate exploratory internal discrimination between pneumonia and post-pneumonia measurements with moderate performance (median balanced accuracy 0.72; median AUROC 0.80;<i>Q</i>²0.24; two latent variables), with a permutation<i>p</i>-value of 0.112. Paired differential analysis identified 104 recovery-associated features (58 higher and 46 lower during pneumonia) meeting |mean log₂fold change| ⩾ 1 and FDR<i>q</i>⩽ 0.05, with putative accurate-mass matches to 239 HMDB accessions. Real-time breathomics captures reproducible changes in exhaled breath mass-spectral profiles from pneumonia to convalescence and reveals breath-profile heterogeneity not fully reflected by standard clinical indices. These results should be interpreted as exploratory and hypothesis-generating, motivating multicenter validation with tandem mass spectrometry-supported compound identification, clinically relevant control groups, and longitudinal outcome linkage.</p>","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149074940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-resolution FAIMS-mass spectrometry for breath analysis using atmospheric pressure chemical ionisation.","authors":"J Diana Zhang, Ezaz Ahmed, Oscar H Lloyd Williams, Merryn Baker, Nicole J Rijs, K M Mohibul Kabir, William A Donald","doi":"10.1088/1752-7163/aeabcd","DOIUrl":"10.1088/1752-7163/aeabcd","url":null,"abstract":"<p><p>Exhaled breath containing volatile organic compounds (VOCs) can be analysed non-invasively and has potential applications in disease diagnosis. Previous high-field asymmetric waveform ion mobility spectrometry (FAIMS)-based breath studies have primarily used low-resolution FAIMS with ion current detection rather than mass spectrometry (MS). Here, atmospheric pressure chemical ionisation (APCI) was coupled with high-resolution FAIMS-MS for direct breath analysis. APCI-FAIMS-MS increased the number of detected breath features by >200% compared with APCI-MS alone and consistently detected 60-130 breath features per sample. Within-participant heatmap consistency was comparable across the four participants based on structural similarity index analysis. Exploratory principal component analysis showed participant-associated clustering of breath profiles. These results demonstrate that high-resolution FAIMS substantially enhances breath feature detection and provides an orthogonal separation dimension for untargeted breath profiling. Future studies involving larger cohorts and disease-specific populations will determine whether the increased breath feature coverage afforded by high-resolution FAIMS can improve VOC-based classification and diagnostic performance.</p>","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149030500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of PTR-ToF-MS for detecting and tracking E-liquid aroma compounds in exhaled breath.","authors":"Joris Meurs, Philipp Kemkes, Evangelia Sakkoula, Simona M Cristescu","doi":"10.1088/1752-7163/aeac7a","DOIUrl":"10.1088/1752-7163/aeac7a","url":null,"abstract":"<p><p>Real-time characterization of e-cigarettes chemical constituents' persistence in the respiratory tract is essential for exposure assessment and health risk evaluation, but has not been previously demonstrated. In this study, proton transfer reaction-time-of-flight-mass spectrometry (PTR-ToF-MS) is integrated with multivariate statistical analysis to select volatile and semi-volatile organic compounds (VOCs) from commercially available e-liquid products and to track their washout kinetics. Participants (= 10) inhaled single puffs from an e-cigarette loaded with unflavoured e-liquid base, or cinnamon, or peppermint/menthol flavour. Exhaled breath samples were collected before and after e-cigarette puff and subsequently analysed with PTR-ToF-MS. Multivariate analysis identified compounds significantly elevated post-vaping (VIP1,0.05), including flavour components and potential thermal degradation products. Real-time washout monitoring (= 3) revealed that e-liquid-related VOCs can be retained for up to 32 min post-vaping, though substantial inter-individual variability was observed. These findings demonstrate the potential of PTR-ToF-MS as a non-invasive tool for real-time breath analysis of e-cigarette exposure, providing insight into the short-term kinetics and retention of e-cigarette constituents. This approach is well-suited for application in larger cohort studies aimed at exposure assessment and toxicokinetic evaluation.</p>","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149061383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mask for individual sampling of tidal and ruminal gas contaminated breath in dairy cows.","authors":"Jaehyun Ko, Jonas Hendricks, Frigga Dohme-Meier, Andreas T Güntner","doi":"10.1088/1752-7163/aeb152","DOIUrl":"https://doi.org/10.1088/1752-7163/aeb152","url":null,"abstract":"<p><p>Standardized breath sampling in dairy cows is helpful for health monitoring and emission control. Yet, controlled measurements of and discrimination between tidal and ruminal gas contaminated breath are challenging. Here, we introduce a sampler designed to collect exhaled breath reproducibly from dairy cows. The system integrates pressure regulators and valves to enable normal breathing patterns. Combined real-time monitoring of CH4 and CO2 concentrations facilitates distinction and separate collection of tidal versus ruminal gas contaminated breath into sampling bags. A comprehensive system-level validation is performed, including sampler inertness testing toward various volatile organic compounds (VOCs). Also sample stability over 14 days is exemplarily assessed with Supel™-Inert Multi-Layer Foil bags across different concentration ranges. The sampling mask is validated on 31 dairy cows (total 1187 samples) using proton-transfer-reaction time-of-flight mass spectrometry to quantify physiologically relevant VOCs, including acetone, ethanol, isoprene, acetic acid, propionic acid and butanoic acid. Overall, this sampler provides a robust, extendable solution for livestock breath sampling and characterization.</p>","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149127619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diagnosing pathogenic DNA from<i>Pneumocystis jirovecii</i>in exhaled breath condensate: a feasibility study.","authors":"Sophie Rex Christensen, Ditte Helene Lundsted, Ditte Høgh Nørholt, Emilie Jensen, Julie Houlind Wittrup, Jonas Abou-Harb, Victoria Dagmar Frank Stentoft, David Fuglsang-Damgaard, Inger Lise Gade","doi":"10.1088/1752-7163/aea9c2","DOIUrl":"10.1088/1752-7163/aea9c2","url":null,"abstract":"<p><p>Pathogen identification in pneumonia is achieved in less than 25% of cases. Diagnosis of Pneumocystis pneumonia relies on a multimodal approach combining clinical, radiological, and immunological assessment with microbiological confirmation, most often by polymerase chain reaction. However, the method cannot reliably distinguish between active infection and colonization because of limited assay standardization and lack of universally accepted interpretive criteria. This pilot study explored whether<i>Pneumocystis jirovecii</i>DNA could be detected in patients with suspected infection (PcP) in exhaled breath condensate (EBC). Ten patients with suspected PcP and ten healthy controls provided oral mouthwash (OW) and EBC samples for real-time PCR.<i>P. jirovecii</i>DNA was detected in both OW and EBC in four patients. Ongoing PcP therapy associated with absence of detectable DNA (<i>p =</i>0.048). Detecting<i>P. jirovecii</i>DNA in EBC is feasible, supporting its potential as a non-invasive diagnostic and monitoring tool. The study was approved by the North Denmark Regional Committee on Health Research Ethics (Journal number N-20190070).</p>","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149001909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reply to Comment on 'Feasibility study on training dogs to detect lung cancer: findings of a retrospective evaluation'.","authors":"Christian Grah, Shiao Li Oei, Steven Ngandeu Schepanski, Hannah Wüstefeld, Katarzyna Blazejczyk, Julia Kalinka-Grafe, Georg Seifert","doi":"10.1088/1752-7163/aeab06","DOIUrl":"https://doi.org/10.1088/1752-7163/aeab06","url":null,"abstract":"","PeriodicalId":15306,"journal":{"name":"Journal of breath research","volume":"20 4","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149110218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}