Journal of breath research最新文献

Introduction: Pulmonary function tests (PFTs) are the gold standard for diagnosing of Chronic obstructive pulmonary disease (COPD). Given its limitation in some scenarios, it is imperative to develop new high-throughput screening methods for biomarkers in diagnosing COPD. This study aims to explore the feasibility of screening novel diagnostic biomarkers based on salivary metabolomics for the limited availability of PFTs and difficulties in implementation at primary care facilities. Methods: Participants were recruited from the outpatient department of West China Hospital. Saliva samples were collected to analyze the metabolites through the UPLC-Q-Exactive Orbitrap-MS platform. The raw data from the mass spectrometer was preprocessed with R software after peak extraction. The Wilcoxon rank sum test, Fold change analysis, PCA and OPLS-DA were used to identify potential biomarkers. The ROC curve was used to assess the diagnostic efficacy of the predictive model generated by potential biomarkers. Results: Saliva samples were collected from 66 patients with COPD and 55 healthy volunteers. Significant differences in the salivary metabolome between COPD patients and healthy controls were identified, with 261 differential metabolites recognized, 16 of which were considered as potential biomarker. The diagnostic model generated by these 16 biomarkers can successfully distinguish COPD patients from healthy people. Conclusions Salivary metabolomic profiling is likely to emerge as a promising method for screening potential diagnostic biomarkers of COPD. Further prospective studies with large sample size are needed to verify the predictive value of these biomarkers in COPD diagnosis. .

Rationale:Chronic obstructive pulmonary disease (COPD) exacerbations significantly contribute to disease progression, hospitalizations, and decreased quality of life. Early detection of exacerbations through non-invasive methods, such as exhaled volatile organic compounds (VOCs), could enable timely interventions. This study aimed to identify and validate candidate VOC biomarkers that are associated with exacerbations and stable phases of COPD, and could contribute to the development of a breath-based monitoring device. Methods:A systematic review was conducted to identify VOCs associated with COPD and exacerbations. VOCs were selected as candidate biomarkers if they were reported in at least two studies by different research groups. These VOCs were then validated using longitudinal exhaled breath data from the TEXACOLD study, where exhaled breath samples were collected at baseline, during exacerbation, and at follow-up in 14 COPD patients. Sparse Partial Least Squares-Discriminant Analysis (sPLS-DA) was applied to differentiate between samples collected during exacerbation and those at stable phases. Diagnostic accuracy was assessed using Receiver Operating Characteristic (ROC) curves. Results:The systematic review identified nine candidate VOCs. Three were excluded from validation because their dataset overlapped with one used in one of the included review studies. Validation confirmed the discriminatory power of a composite model of these six VOCs, achieving an area under the ROC curve of 0.98, a diagnostic accuracy of 94.3% and a sensitivity of 0.97 and a specificity of 0.93. Conclusion:This study demonstrates that exhaled VOCs can differentiate between exacerbations and stable phases in COPD patients. The validated biomarkers hold promise for future clinical applications, particularly in the development of a non-invasive, breath-based monitoring device for early detection and management of COPD exacerbations, potentially reducing hospitalizations and improving patient outcomes.

The measurement of exhaled carbon monoxide (eCO) is relevant to understanding normal physiology and disease states but has been limited by deficiencies in valid sampling protocols, accurate and feasible measurement methods, and the understanding of normal physiological variation. The purposes of this study were (1) to compare the three collection methods for eCO and (2) to gain a better understanding of patterns of normal variation by obtaining repeated daily and weekly measurements. We compared three techniques to sample eCO: continuous breathing (ConB), breath-holding (BrH), and short rebreathing (SrB). We used a Carbolyzer mBA-2000 instrument that involves an electrochemical method to quantify CO, with the final value corrected for ambient CO. In Phase I, we compared ConB with BrH in 10 healthy non-smokers (5 male, five female). On day 1, the eCO was determined from 0730 to 1700 (11 samples), and the first four morning time points were repeated on days 7, 14, and 21. ConB had a lower eCO than BrH, and eCO2 was frequently below the threshold of 4.6% compatible with inadequate alveolar sampling. The eCO measured by the ConB and BrH methods increased during the day and showed week-to-week variability. In Phase II, we compared the BrH and SrB techniques by collecting prebreakfast samples weekly for four weeks in 30 healthy non-smokers (15 male,15 female). Comparing the SrB vs. the BrH method, SrB was the easier for the participants to perform, generated higher eCO (~0.5 ppm), and produced higher eCO2 levels (5.2% ± 0.3 vs. 5.0% ± 0.2); Importantly, Phase II study revealed that week-to-week changes in prebreakfast fasting eCO for individual participants were ≥1.0 ppm in ~37%. This variability complicates the interpretation of the relationship between small changes in eCO and the underlying physiological or disease states.

Small intestinal bacterial overgrowth (SIBO) and extraoral halitosis are often observed in functional dyspepsia (FD). We aimed to identify their associations for the first time. In this study, extraoral halitosis was diagnosed and assessed through the organoleptic score (OLS). Total symptom score (TSS) of FD, SIBO, gastricHelicobacter pylori(H. pylori) infection, and three exhaled volatile sulfur compounds (VSCs) (hydrogen sulfide, methyl mercaptan, and dimethyl sulfide (DMS)), were evaluated. Finally, 63 non-halitosis patients and 45 halitosis patients with extraoral halitosis were identified. Compared to non-halitosis patients, halitosis patients exhibited significantly higher TSS (86 [56, 123] vs 43 [34, 57],P< 0.001) and SIBO positivity rate (66.67% vs 11.11%,P< 0.001), but similarH. pyloripositivity rate. The adjusted odds ratios of TSS and SIBO were 1.06 and 5.02, respectively. The area under curve of the combination of TSS and SIBO for predicting extraoral halitosis was 0.89. Positive correlations were observed between TSS and OLS (r= 0.64), and between TSS and exhaled DMS level (r= 0.86), respectively. The other two VSCs were undetectable or of little value. We conclude that: (1) Extraoral halitosis is closely associated with FD and SIBO; (2) DMS is its primary contributing VSC; (3) FD patients with SIBO as opposed to gastricH. pyloriinfection are more prone to extraoral halitosis; (4) Clinicians should be aware of SIBO in the management of extraoral halitosis in FD.

Lung cancer is one of the most common malignancy in the world, and early detection of lung cancer remains a challenge. The exhaled breath condensate (EBC) from lung and trachea can be collected totally noninvasively. In this study, our aim is to identify differential metabolites between non-small cell lung cancer (NSCLC) and control EBC samples and discriminate NSCLC group from control group by orthogonal projections to latent structures-discriminant analysis (OPLS-DA) models. The EBC differential metabolites between NSCLC patients (n= 29) and controls (n= 24) (20 healthy and 4 benign individuals) were identified using ultra-performance liquid chromatography-high resolution mass spectrometry based untargeted metabolomics method. The upregulated metabolites in EBC of NSCLC included amino acids and derivatives (phenylalanine, tryptophan, 1-carboxyethylisoleucine/1-carboxyethylleucine, and 2-octenoylglycine), dipeptides (leucyl-phenylalanine, leucyl-leucine, leucyl-histidine/isoleucyl-histidine, and prolyl-valine), and fatty acids (tridecenoic acid, hexadecadienoic acid, tetradecadienoic acid, 9,12,13-trihydroxyoctadec-10-enoic acid/9,10,13-trihydroxyoctadec-11-enoic acid (9,12,13-TriHOME/9,10,13-TriHOME), 3-hydroxysebacic acid/2-hydroxydecanedioic acid, 9-oxooctadeca-10,12-dienoic acid/9,10-Epoxy-12,15-octadecadienoate (9-oxoODE/9(10)-EpODE), and suberic acid). The downregulated metabolites in EBC of NSCLC were 3,4-methylenesebacic acid, 2-isopropylmalic acid/3-isopropylmalic acid/2,3-dimethyl-3-hydroxyglutaric acid, and trimethylamine-N-oxide. The OPLS-DA model based on 5 EBC metabolites achieved 86.2% sensitivity, 83.3% specificity and 84.9% accuracy, showing a potential to distinguish NSCLC patients from controls.

Halitosis presents a significant global health concern, necessitating the development of precise and efficient testing methodologies owing to the high prevalence and the associated social and psychological effects. The measurement of volatile sulfur compounds (VSCs), recognized as primary contributors to halitosis, is particularly significant. While gas chromatography (GC-MS) offers accurate measurements, its bulky and expensive nature limits widespread accessibility. Hence, this study endeavors to devise a compact yet highly accurate AI-based halitosis measurement apparatus, termed 'Kunkun dental' and validate its efficacy. Specifically, we intend to compare the VSC concentrations obtained from halitosis patients' breath samples using Kunkun dental against those from conventional GC-MS to assess the criterion validity of the new testing method. The study cohort comprised 68 halitosis patients aged 20 years or older, attending the breath freshening outpatient clinic at Tokyo Medical and Dental University Hospital between October 2022 and March 2023, who consented to participate and underwent routine measurements. Participants completed an age and sex questionnaire, while VSC concentrations were determined using both GC-MS and Kunkun dental (H₂S, CH₃SH, (CH₃)₂S), enabling a comparative analysis of the results. Pearson product-moment correlation coefficients between GC-MS and Kunkun dental indicated significant correlations for all three gases: 0.719 for H₂S, 0.821 for CH₃SH, and 0.637 for (CH₃)₂S. Moreover, sensitivity and specificity in accordance with the predefined thresholds were confirmed, and their values ranged from 0.59 to 0.86 and 0.53-0.77, respectively. Furthermore, grouping Kunkun dental measurements into low-, medium-, and high-concentration groups revealed significantly higher GC-MS VSC concentrations in samples with elevated Kunkun dental readings. The amalgamation of AI technology and a semiconductor gas sensor holds great promise in creating a compact and precise halitosis analyzer. This study underscores the feasibility and effectiveness of Kunkun dental as a reliable tool for halitosis assessment, affirming its utility in clinical practice.

Sarcoidosis is considered a T-helper (Th) 1 related disease, but a transition from Th1 to Th2 pathway activation has been postulated in sarcoidosis-associated pulmonary fibrosis (SAPF). Fraction of exhaled nitric oxide (F_ENO) is a marker of Th2 airway inflammation, but alveolar concentration of nitric oxide (C_ANO) can be measured to assess Th2 inflammation in the periphery of the lung. The aim of this study is to assess whether C_ANO can be considered a biomarker of SAPF or active pulmonary sarcoidosis. In this single-center retrospective study, we compared exhaled NO levels of patients with pulmonary sarcoidosis without fibrosis (N= 11) with those obtained from patients with SAPF (N= 15). Clinical data, as well as respiratory function tests, were also analyzed. F_ENO (28.5 ± 16 ppb vs 30.9 ± 17.2 ppb,p= 0.72) and C_ANO (4.4 ± 3.5 ppb vs 3.2 ± 1.7 ppb,p= 0.73) levels did not differ significantly between patients with or without SAPF, even when dividing them according to treatment or disease activity. C_ANO appeared reduced in patients with active sarcoidosis (2.1 ± 0.8 ppb vs 4.1 ± 3 ppb,p< 0.05). In conclusion, C_ANO cannot be considered a biomarker of SAPF. Its lower level in patients with active disease confirms the prevalence of Th1 inflammation in granuloma formation and suggests its potential role as a biomarker of active pulmonary sarcoidosis, but further studies with larger samples are needed to confirm this hypothesis.

The concentrations of nasal nitric oxide (nNO) vary in patients with chronic rhinosinusitis (CRS) supposedly depending upon whether the paranasal ostia are open or obstructed. Our aim was to assess whether nNO levels and their response to topical xylometazoline (a local vasoconstrictor used to alleviate nasal congestion) in patients with CRS differ between those with open or obstructed ostia and if the results were altered by the use of nasal corticosteroids. Sixty-six patients with CRS (43% with nasal polyps) or recurrent acute rhinosinusitis and 23 healthy controls were included. Nasal NO was measured (EcoMedics CLD 88p analyser) before and after two xylometazoline sprays during three consecutive visits: with the medication they were using when they were referred, after 4 weeks of medication pause, and after 4 weeks of using intranasal fluticasone propionate. The relative difference between the nNO before and after dosing of xylometazoline was calculated, and ostial obstruction was evaluated with cone-beam computed tomography at every visit. The nNO measurements were lowest in the patients with CRS and obstructed paranasal ostia. The presence or absence of nasal polyps did not affect the results. Xylometazoline did not significantly affect nNO in the subjects with obstructed ostia, but there was a significant reduction of nNO in those with open ostia. The Xylometazoline-induced change in nNO between the groups with open or obstructed ostia was significantly different at each visit: 'on previous medication' 10% (-5-25) versus -14% (-19 to -9),p= 0.004, 'after medication pause' 6% (-5-17) versus -16% (-23 to -9),p= 0.001 and 'after regular fluticasone spray' 6% (-3-15) versus -9% (-16 to -3),p= 0.04. The native nNO and xylometazoline-induced change in nNO can be used to detect the status of ostial obstruction in patients with CRS irrespective of their topical corticosteroid usage.

Halitosis specialists can be found all over the world, but very little is known about how they approach patients with halitosis complaints. Therefore, this web-based questionnaire study tried to reach as many of them to gain insight in their methods and tools used to diagnose the condition. Since this study was carried out in the aftermath of the COVID-19 pandemic, its impact was also examined. This survey encompassed 19 questions interrogating the responders' profile; their diagnostic process in general; the methods and tools used to examine the breath; and the impact of COVID-19 on them. It was accessible online from May till October 2022. Eighty halitosis professionals from 19 different countries replied. Their answers showed that the community behind the field of halitosis seems to be largely driven by oral health professionals. The respondents had been active in this niche for on average 12 years in consultations (41%), research (23%) or a combination (36%). To achieve a diagnosis 96% believed a thorough history is a must and 94% felt that a breath odor examination (instrumental and/or organoleptically) was necessary. The Halimeter® was the most common instrument used for breath odor analysis. There was a large variation in the organoleptic examination regarding the calibration and number of judges and the specific odors sources that were assessed (i.e. mouth odor versus nose odor). Less variation was noted on the rating scale used: 87% made use of the 6-point odor strength scale. For those that performed organoleptic examinations COVID-19 forced them to modify their examination (20%) or to stop performing it (67%). This international survey showed that there is not a consensus between specialists on how the diagnosis of halitosis should be carried out. However, a common thread can be noted: thoroughly interviewing the patients and examining the breath odor are of upmost importance.

Halitosis has a multifactorial etiology being of interest by different health areas. The aim of this study was to perform a bibliometric and altmetric analyzes of the top 100 most-cited papers on halitosis to provide a comprehensive view of their scientific and alternative metrics. This would give perspectives on citation dynamics and online attention of the research outputs. A search strategy was designed, tested and applied in the Web of Science database on August 1st, 2023. The 100 most-cited papers were selected by two reviewers. Data on title, year of publication, number of citations, authorship, journal title, study design, halitosis etiology and subject/field of the study or pathogenesis of halitosis were extracted from each paper. Altmetric attention score (AAS) for each paper was registered. Papers were published between 1972 and 2019. Most cited papers were non-systematic reviews (28%). USA was the country with the greatest number of publications (20%). Journals with the greater number of citations were related to dentistry. The altmetric analysis did not show correlation with the citation count but showed a few papers with elevated AAS and a good diffusion in social media. The level of evidence of the study design did not influence the citation number. This can indicate the need for citing studies with more robust designs in order to provide better scientific evidence of citations in epidemiology, etiology, diagnosis and treatment. Databases showed positive correlation among citation counts, but no correlation with the online attention.