Breath Condensate Research Articles

Functional analysis of airway remodeling is related with fibrotic mediators in asthmatic children

Background Asthmatic children present variable degrees of airway inflammation, remodeling, and resistance, which correlate with disease control and severity. The chronic inflammatory process of the airway triggers airway remodeling, which reflects the degree of airway resistance. Pro-inflammatory and pro-fibrotic mediators are centrally involved in this process. Objective To investigate whether the levels of pulmonary and systemic pro-inflammatory and pro-fibrotic mediators present a correlation with the resistance of the respiratory system and of the proximal and distal airways. Methods 39 Asthmatic children (persistent mild and moderate) and 39 non-asthmatic children (both between 6 and 13 years old) were evaluated for anthropometric characteristics, lung function and mechanics, and pulmonary and systemic immune responses. Results Asthmatic children showed an increased number of blood eosinophils (p < 0.04), basophils (p < 0.04), monocytes (p < 0.002) and lymphocytes (p < 0.03). In addition, asthmatic children showed impaired lung function, as demonstrated by FEV1 (p < 0.0005) and FEV1/FVC (p < 0.004), decreased total resistance of the respiratory system (R5Hz; p < 0.009), increased resistance of the proximal airways (R20Hz; p < 0.02), increased elastance (Z5Hz; p < 0.02) and increased reactance (X5Hz; p < 0.002) compared to non-asthmatic children. Moreover, the following inflammatory factors were significantly higher in asthmatic than non-asthmatic children: GM-CSF in the breath condensate (BC) (p < 0.0001) and in the serum (p < 0.0001); TGF-beta in the BC (p < 0.0001) and in the serum (p < 0.004); IL-5 in the BC (p < 0.02) and in the serum (p < 0.01); IL-4 in the serum (p < 0.0002). Conclusions Impulse oscillometry is a sensitive method to detect airway resistance in persistent mild and moderate asthmatic children, an event followed by increased levels of pro-inflammatory and pro-fibrotic mediators.

Protocol for a mixed-method study to assess chronic cough in patients with renal cell carcinoma: the prevalence, impact on quality of life, trigger and potential clinical application of chronic cough as an early screening tool in patients with kidney cancer

IntroductionCough as a symptom of renal cell carcinoma (RCC) was first described by Creevy in 1935, and despite one (unpublished) study suggesting it may affect 31% of these patients, as...

Advancements in Rapid and Affordable Diagnostic Testing for Respiratory Infectious Diseases: Evaluation of Aptamer Beacon Technology for Rapid and Sensitive Detection of SAR-CoV-2 in Breath Condensate.

The demand for rapid and efficient diagnostic point-of-care tests for respiratory infectious diseases has become increasingly critical in the current landscape. The emphasis on accessibility has been underscored over the past year, making it crucial to have biological components that exhibit fast and accurate kinetics. The foundation for precise, swift, and effective testing relies on the availability of highly responsive biological agents. Two published aptamer DNA sequences designated Song and MSA52 and their truncated internal stem-loop structures were studied for their potential to serve as aptamer beacons for rapid COVID detection. The candidate beacons were covalently labeled with Atto 633 dye attached to their 5' ends and Iowa Black quencher attached to their 3' ends. The whole aptamer structures exhibited the greatest fluorescence signal intensities and higher fluorescence background than their truncated internal stem-loop beacon structures suggesting that the distance between fluorophores and quenchers was greater for the whole aptamer beacon candidates versus the isolated stem-loop structures. Beacon candidates were tested against two heat- or gamma radiation-killed SARS-CoV-2 Washington 1/2020 virus samples and three different COVID spike (S) proteins to test their effectiveness. Despite the higher background fluorescence, the whole aptamer beacons showed better signal-to-noise ratios and were selected for further investigation. Limit of detection (LOD) studies revealed that both the whole Song and whole MSA52 aptamer beacon candidates had a LOD of 9.61 × 103 genome equivalents in phosphate-buffered saline using the red channel of a Promega Quantus™ fluorometer which correlated well with confirmatory spectrofluorometry. Cross-reactivity studies using numerous COVID variants, related coronaviruses, and other common respiratory pathogens suggested greater COVID selectivity for the whole MSA52 versus the whole Song aptamer beacon candidate, indicating promise for specific COVID detection. Importantly, both whole aptamer beacon candidates exhibited very rapid "bind and detect" fluorescence increases within the first 1-2min of mixing the beacons with killed SARS-CoV-2 viruses in 100µl samples. Overall, this work illustrates the strong potential for aptamer beacons for rapid, on-site detection and presumptive diagnosis of COVID in breath condensates or other small liquid samples. This research highlights the strong potential of aptamer beacons for addressing the need for fast and convenient diagnostic tools in global health contexts, especially in resource-limited settings.

Physical Training Reduces Chronic Airway Inflammation and Mediators of Remodeling in Asthma.

Several benefits of aerobic training for asthmatic patients have been demonstrated. However, its effects on systemic inflammation and on airway remodeling mediators and lung mechanics are unknown. This prospective study included 21 intermittent and mild asthma patients, and as primary outcomes, the evaluation of pro- and anti-inflammatory and pro- and antifibrotic mediators in exhaled breath condensate (EBC) and blood were performed, beyond the cell counting in blood and in induced sputum. Aerobic training was performed for 3 months, 3 times per week. Aerobic training increased the levels of anti-inflammatory cytokines and of antifibrotic mediators in the breath condensate: IL-1ra (p = 0.0488), IL-10 (p = 0.0048), relaxin-3 (p = 0.0019), and klotho (p < 0.0043), respectively. Similarly, in plasma, increased levels of IL-1ra (p = 0.0147), IL-10 (p < 0.0001), relaxin-3 (p = 0.004), and klotho (p = 0.0023) were found. On contrary, reduced levels of proinflammatory cytokines in the breath condensate, IL-1β (p = 0.0008), IL-4 (p = 0.0481), IL-5 (p < 0.0001), IL-6 (p = 0.0032), IL-13 (p = 0.0013), and TNF-α (p = 0.0001) and profibrotic markers VEGF (p = 0.0017) and TSLP (p = 0.0056) were found. Similarly, in plasma, aerobic training significantly reduced the levels of proinflammatory cytokines IL-1β (p = 0.0008), IL-4 (p = 0.0104), IL-5 (p = 0.0001), IL-6 (p = 0.006), IL-13 (p = 0.0341), and TNF-α (p = 0.0003) and of profibrotic markers VEGF (p = 0.0009) and TSLP (p < 0.0076). Fractional exhaled nitric oxide (FeNO) was reduced after the intervention (p = 0.0313). Regarding inflammatory cells in sputum, there was a reduction in total cells (p = 0.008), eosinophils (p = 0.009), and macrophages (p = 0.020), as well as of blood eosinophils (p = 0.0203) and lymphocytes (p = 0.0198). Aerobic training positively modulates chronic airway inflammation and remodeling mediators, beyond to improve systemic inflammation in intermittent and mild asthmatic patients.

Combined resistance and aerobic training improves lung function and mechanics and fibrotic biomarkers in overweight and obese women.

Background: Obesity impairs lung function and mechanics and leads to low-grade inflammation, but the effects of combined physical exercise (CPE) on that are unknown. Methods: We investigated the effects of 12 weeks of combined physical exercise (aerobic + resistance training), in non-obese (n = 12), overweight (n = 17), and obese grade I (n = 11) women. Lung function and lung mechanics were evaluated. The systemic immune response was evaluated by whole blood analysis and biomarker measurements, while pulmonary fibrotic biomarkers were evaluated in the breath condensate. Result: CPE improved forced vital capacity (FVC) % (p < 0.001) and peak expiratory flow (PEF) % (p < 0.0003) in the obese group; resistance of the respiratory system (R5Hz) in non-obese (p < 0.0099), overweight (p < 0.0005), and obese (p < 0.0001) groups; resistance of proximal airways (R20Hz) in non-obese (p < 0.01), overweight (p < 0.0009), and obese (p < 0.0001) groups; resistance of distal airways (R5Hz–R20Hz) in non-obese (p < 0.01), overweight (p < 0.0012), and obese (p < 0.0001) groups; reactance of the respiratory system (X5Hz) in non-obese (p < 0.01), overweight (p < 0.0006), and obese (p < 0.0005) groups; impedance of the respiratory system (Z5Hz) in non-obese (p < 0.0099), overweight (p < 0.0005), and obese (p < 0.0001) groups; central resistance (RCentral) in non-obese (p < 0.01), overweight (p < 0.001), and obese (p < 0.0003) groups; and the peripheral resistance (RPeripheral) in non-obese (p < 0.03), overweight (p < 0.001), and obese (p < 0.0002) groups. CPE reduced the pro-fibrotic IGF-1 levels in BC in overweight (p < 0.0094) and obese groups (p < 0.0001) and increased anti-fibrotic Klotho levels in BC in obese (p < 0.0001) groups, and reduced levels of exhaled nitric oxide in overweight (p < 0.03) and obese (p < 0.0001) groups. Conclusion: CPE improves lung function, mechanics, and pulmonary immune response in overweight and obese grade I women by increasing anti-fibrotic protein Klotho and reducing pro-fibrotic IGF-1.

Aluminium Gauze Reduces SARS-CoV-2 Viral Load in Non-Woven Masks Worn by Patients with COVID-19.

Background: Aluminium reduces severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) survival in experimental settings. It is unknown whether adding an aluminium gauze to a mask reduces the SARS-CoV-2 RNA load in the mask and whether SARS-CoV-2 is detectable in the breath that permeates through such a mask in clinical settings. Methods: Patients admitted to Kishiwada City Hospital, Osaka, Japan, between July 2021 and September 2021 were enrolled in the study. Non-woven masks comprising filters with 99% viral filtration efficacy and aluminium and cotton gauzes attached to plastic collection cases were developed. All participants wore the experimental mask models for three hours. Results: Twenty-nine patients who wore the final model masks were analysed in this study. The Ct values of the nucleocapsid gene and envelope gene of SARS-CoV-2 were significantly higher in the aluminium gauze than in the cotton gauze. SARS-CoV-2 RNA was detected in the masks of 8 out of 12 vaccinated patients (66.7%). Although breath condensates were collected behind both aluminium and cotton gauzes, SARS-CoV-2 RNA was not detected in these condensates. Conclusions: Our study indicated that non-woven masks with an aluminium gauze may obstruct SARS-CoV-2 transmission in clinical settings better than non-woven masks with cotton gauzes.

Engineered Electroactive Solutions for Electrochemical Detection of Tuberculosis-Associated Volatile Organic Biomarkers.

Rapid screening of tuberculosis by evaluation of associated volatile organic biomarkers in breath is a promising technology that is significantly faster and more convenient than traditional sputum culture tests. Methyl nicotinate (MN) and methyl p-anisate (MPA) have been isolated as potential biomarkers for mycobacterium tuberculosis and have been found in the breath of patients with active pulmonary tuberculosis. A novel approach to detection of these biomarkers in liquid droplets (e.g. from breath condensate) using inexpensive screen-printed electrodes is presented. Previous modelling studies suggest that these biomarkers complex with certain transition metals of particular valence state. This interaction can be exploited by mixing the biomarker sample into an electroactive solution (EAS) containing the functional metal ion and observing the change electrochemically. The study focuses on low biomarker concentrations, determined to be clinically relevant based on preliminary GC-MS studies of the levels found in patient breath. It was found that both the cyclic voltammogram and square wave voltammogram of copper(II) change significantly when as little as 0.1 mM MN is added to the solution, with analysis times of less than 2 min. Copper(II) exhibits three separate peaks during square wave voltammetry. The location and area of each peak are affected differently as the concentration of MN increases, suggesting a reaction with specific oxidation states of the metal. In this way, a "fingerprint" method can be used to identify biomarkers once their known interaction is established.

AEROBIC TRAINING MODULATE PULMONARY AND SYSTEMIC INFLAMMATORY AND FIBROTIC RESPONSE IN PATIENTS WITH ASTHMA

TOPIC: Pulmonary Rehabilitation TYPE: Original Investigations PURPOSE: Airway remodeling is a hallmark of asthma, characterized by structural changes in the airways, including epithelial metaplasia, subepithelial fibrosis, angiogenesis and thickening of smooth muscle. Airway remodeling promotes irreversible loss of lung function and subside the airway hyperresponsiveness and is associated with severity of the disease. In addition, airway remodeling is caused by an unresolved chronic inflammatory response, involving exacerbated release of profibrotic mediators. Aerobic exercise (AE) is the main component of pulmonary rehabilitation and in pre-clinical studies in models of asthma, AE reduced airway remodeling, by reducing the release of pro-fibrotic mediators and increasing the release of anti-fibrotic mediators. However, no clinical study has tested whether AE could promote any effect on airway remodeling in asthmatic patients. METHODS: Treadmill aerobic exercise (AE) (12 weeks, 3x/week, 40min/session, 60-80%MaxHR) was applied to 17 persistent moderate asthmatic patients (42.11±19.13). Body mass index (BMI), lung function, induced sputum, breath condensate, whole blood analysis and CD4+ cells proliferation, 6MWT, exhaled nitric oxide, was evaluated. RESULTS: AE improved VEF3 (L) (p<0.03) and PEF (L/min) (p<0.005) and PEF (%) (p<0.004), reduced the number of total leukocytes, eosinophils, neutrophils, lymphocytes and macrophages (p<0.01), as well as the levels of IL-1beta, IL-4, IL-5, IL-6, IL-8, IL-13, IL-17, IL-23 (p<0.01) in induced sputum. AE also reduced the levels of IL-1beta, IL-5, IL-6, IL-13, VEGF (p<0.01), while increased the levels of anti-inflammatory IL-1ra and IL-10 (p<0.01) and anti-fibrotic Relaxin 3 (p<0.01) in breath condensate. Systemically, AE reduced the number of eosinophils, neutrophils and lymphocytes (p<0.01), as well as the levels of IL-1beta, IL-5, IL-6, IL-13, VEGF (p<0.01), while increased anti-inflammatory IL-1ra, IL-10 (p<0.01) and anti-fibrotic Relaxin 3 (p<0.01) in plasma. AE improved 6MWT (p<0.01) and reduced exhaled nitric oxide (p<0.01) and CD4+ cells proliferation (p<0.01). CONCLUSIONS: In conclusion, AE improves airway and systemic inflammation reducing pro-inflammatory cytokines, while increased anti-inflammatory and anti-fibrotic mediators systemically and into the lungs. CLINICAL IMPLICATIONS: These findings present unprecedented findings on auxiliary treatment and prevention of the health consequences of people with asthma through the practice of physical exercise. From a social point of view, it demonstrates a low-cost and easily accessible intervention, while from a scientific point of view, it will promote research ideas in a promising field. DISCLOSURES: No relevant relationships by thiago alves, source=Web Response no disclosure on file for Helida Aquino-Santos; No relevant relationships by RENILSON FERREIRA, source=Web Response no disclosure on file for Claudio Frison; No relevant relationships by Victor Hugo Palmeira, source=Web Response No relevant relationships by 119 Maysa Alves Rodrigues Rangel, source=Web Response No relevant relationships by Anamei Silva-Reis, source=Web Response No relevant relationships by Rodolfo Vieira, source=Web Response

Isolation, characterisation and detection of breath-derived extracellular vesicles

The physical characterisation, capture and detection of extracellular vesicles (EVs) and exosomes derived from breath condensate is reported. Breath-derived EVs were isolated from breath condensate and captured on a gold substrate using two complimentary methods. The characterised and isolated EVs were detected using surface plasmon resonance (SPR) and electrochemical impedance spectroscopy (EIS). EIS was done using aptamers as a targeting moiety and showed a larger change in resistance between dilute concentrations of EVs (less than 7 μg/mL).This is the first report of EVs and exosomes isolated and characterised from breath. In addition, EVs from a non-invasive and easily available source such as breath opens up further avenues in the detection of pulmonary diseases.

Electrochemical Sensing Platforms for Tuberculosis-Associated VOCs from Patient Breath

In this presentation two point-of-care electrochemical sensing platforms (gas and liquid phase) to detect volatile organic compounds (VOCs) present in the breath of tuberculosis (TB) patients will be discussed. Rapid screening using patient breath is significantly faster, less expensive and more convenient than traditional sputum-based tests, and up to one third of adults and the majority of young children with TB are unable to produce sufficient sputum for traditional culture testing, making the development of non-sputum-based tests a priority in TB screening and diagnostics. Methyl nicotinate (MN) and methyl p-anisate (MPA) have been identified as specific biomarkers for TB in patient breath and culture by GC-MS [1], and are not found in readily in ambient air or the breath of healthy patients, making them good candidates for TB screening. Previous modelling studies [2] suggest that these biomarkers complex with certain transition metals (such as cobalt and copper) given a particular bias voltage and oxidation state of the metal. This known interaction was used as the basis for the sensing platforms described.A solid-state titanium dioxide nanotube array-based sensor is used to directly detect TB biomarkers in the gas phase, utilizing a divalent cobalt-functionalized surface (Co-TNA) to specifically bind MN and MPA [3]. The original sensor design consisted of a simple two-electrode setup and chronoamperometry at binding voltages specific to the VOCs of interest was used to selectively sense these biomarkers. However, the lack of a separate reference electrode in this system can cause a high level of variability in the sensors, limiting sensitivity and specificity. In order to improve reproducibility and specificity, a solid-state, electron-conductive polymer “electrolyte” of known resistance is used to create a gas-phase three-electrode system, utilizing silver screen-printed references and counter electrodes. This new configuration ensures more consistent interactions with the analyte of interest between sensors in the amperometric mode, and allows the sensor to be operated using more complex scanning techniques traditionally used in liquid systems. Scanning potential methods such as cyclic voltammetry (CV) have shown promise in detecting these VOCs more specifically than chronoamperometry alone. For example, the CV of a Co-TNA sensor shows a reduction peak at about -0.5 V vs the silver quasi-reference electrode when exposed to methyl nicotinate vapor which is not present when exposed to simple humid air (figure 1). In preliminary field studies, CVs of the Co-TNA sensor in response to the breath of sick patients show artifacts not present in healthy controls. Results comparing suspected TB patients (Xpert positive and negative) as well as healthy controls will be presented.Because the VOCs associated with Tuberculosis are only semi-volatile and readily dissolve in water at significantly high concentrations (mM range), collection of these compounds from breath and condensate into an aqueous solution can provide a simple concentration method when very low levels of VOC are present. In addition, breath condensate can be frozen and saved for later analysis when immediate testing is not available. Therefore, we have developed a liquid-phase sensing platform utilizing engineered electroactive solutions (EASs) containing a functional metal ion which can be customized to the analyte of interest without the need for a more expensive, highly specific working electrode as used in the gas-phase platform. Rather than observing interactions of the biomarker at the specific electrode surface, a functional metal solution of known electrochemical activity is used to detect the VOC of interest by observing the change electrochemically when it is added to the EAS. In this application, copper is preferred over cobalt because of its highly reversible redox reactions and the ability to observe multiple redox peaks within a relatively small potential window. Testing of this platform with a divalent copper EAS has shown that the cyclic voltammogram of a copper redox pair changes significantly when as little as 1 mM methyl nicotinate (MN) is added to the solution. The variation of peak oxidation voltage with MN concentration can be seen in figure 2. In order to further understand the reactions taking place and specifically identify the biomarkers, square wave voltammetry (SWV) is employed to show which oxidation states of the functionalized metal are complexing with the biomarker of interest. The SWV for the copper EAS alone shows three distinct peaks for each of the redox reaction couples present in the voltage window (less than ±1 V). When a small amount of MN is added, the size, shape and in some cases peak-voltage of each distinct peak is affected differently, implying a difference in reaction to specific valence states of copper (figure 3). When methyl p-anisate (MPA) was added at the same concentration, different interactions were observed. In this way, a “fingerprint” method can be used to identify biomarkers once their known interaction is established.

Inflammation in children with neuromuscular disorders and sleep disordered breathing

IntroductionPaediatric obstructive sleep apnoea is associated with systemic inflammation and co-morbidities. We assessed whether sleep disordered breathing (SDB) due to neuromuscular weakness was associated with elevated airway and systemic pro-inflammatory cytokines. MethodsConsecutive neuromuscular children (age 5–18years) underwent overnight full polysomnography and morning collection of serum and breath condensate, analysed for cytokines (Interleukin-10, Interleukin-6, Interleukin-1β, Tumour Necrosis Factorα, high-sensitivity C-Reactive Protein, Intercellular and Vascular Adhesion Molecules ICAM-1, VCAM-1). Cytokine levels were related to Oxygen desaturation index (ODI), desaturation>4%/h, and levels of transcutaneous carbon dioxide overnight (tcCO2≥6.7 kPa > 2% sleep). ResultsA total of 23 patients were included, median age 12.6 years (IQR 8.7–14.6). ODI>3/h was associated with higher breath and serum IL-6 (p = 0.02). Children with elevated CO2 overnight had higher ICAM-1 and VCAM-1. CO2 levels correlated with serum ICAM-1 (rs0.570, p = 0.026) and VCAM-1 (rs0.76, p = 0.001). DiscussionSDB in neuromuscular children is associated with raised serum IL-6, VCAM-1, ICAM-1. This may predispose these children to future cardiovascular and other co-morbidities.

Early-life origin and prevention of chronic obstructive pulmonary diseases.

Chronic obstructive respiratory disorders such as asthma and chronic obstructive pulmonary disease (COPD) have their roots in the womb. Together with a genetic predisposition, prenatal and early-life factors, including maternal smoking, prematurity, and bronchopulmonary dysplasia (BPD), have a pivotal role in later respiratory health. Then, inappropriate responses to respiratory viruses (especially respiratory syncytial virus and rhinovirus) and early allergic sensitization are the strongest contributors to the inception of wheezing and early-onset asthma. There is an urgent need for early disease biomarkers to identify profiles at higher risk of chronic respiratory conditions. Applying the "-omic" technologies to urine, blood and breath condensate, and non-invasive inflammometry seem promising in this regard. The description of specific risk profiles may be the key to the use of targeted personalized therapies.

A sampler prototype for the simultaneous collection of exhaled air and breath condensate.

Exhaled air and breath condensate contain a large number of health biomarkers, such as volatile and semi-volatile organic compounds, proteins and lipids. Nowadays, the collection of breath samples is carried out by commercial or lab-made sampling systems that collect only one type of sample (e.g. gaseous or condensate phase), thus limiting the diagnostic capability of breath tests. This work presents a portable prototype optimized for the simultaneous collection of gaseous exhaled breath and exhaled breath condensate within five minutes. The system is fully portable and has a total weight of about 1 Kg. An illustrative determination of ethanol, isoprene, acetone, isopropyl alcohol, 1-propanol, 2-butanone, 2-pentanone, toluene and xylenes in breath, and cortisol and 8-iso-prostaglandin F2α in breath condensate is discussed.

Engineered Electroactive Solutions for Electrochemical Detection of Volatile Organic Biomarkers Associated with Disease

Rapid screening of tuberculosis (TB) by evaluation of associated volatile organic biomarkers (VOBs) in breath has been shown to be a promising technology that is significantly faster and more convenient than traditional sputum culture tests. Methyl nicotinate and methyl p-anisate have been isolated as specific biomarkers for the mycobacterium tuberculosis, as they are not found in high concentrations in ambient air or the breath of healthy patients, but should be readily present in all patients with active TB. A novel approach to detection of these biomarkers in liquid form (e.g. from breath condensate) using inexpensive screen-printed electrodes will be presented. Previous modelling studies [1] suggest that these biomarkers complex with certain transition metals (such as cobalt and copper) given a particular bias voltage and oxidation state of the metal. This interaction can be exploited by mixing the sample solution containing the biomarkers into an electroactive solution (EAS) containing the functional metal ion, and observing the change electrochemically. For example, the cyclic voltammogram of copper (II) changes significantly when as little as 1 mM methyl nicotinate (MN) is added to the solution. The variation of peak oxidation voltage with MN concentration can be seen in Figure 1 below. In order to further understand the reactions taking place and specifically identify the biomarkers, square wave voltammetry (SWV) is employed to show which oxidation states of the functionalized metal are complexing with the biomarker of interest. Figure 2 shows the SWV of a copper EAS with and without 1 mM MN. The SWV shows a peak for each redox transition of copper, and how the area of each is affected by the addition of the biomarker. In this way, a “fingerprint” method can be used to identify biomarkers once their known interaction is established. [1] Ray R, Sarma B, Mohanty S, Prisbrey K, Misra M. Assessment of metals in detection of TB biomarkers: Novel computational approach. Journal of Materials Chemistry and Physics. 161 (2015) 1-8 Figure 1

Minimally invasive biomarker studies in eosinophilic esophagitis: A systematic review

BackgroundEosinophilic esophagitis (EoE) is a chronic, inflammatory disease of the esophagus that currently requires repeated endoscopic biopsies for diagnosis and monitoring because no reliable noninvasive markers have been identified. ObjectiveTo identify promising minimally invasive EoE biomarkers and remaining gaps in biomarker validation. MethodsWe performed a systematic review of EMBASE, Ovid MEDLINE, PubMed, and Web of Science from inception to June 6, 2017. Studies were included if patients met the 2007 consensus criteria for EoE diagnosis, a minimally invasive biomarker was assessed, and the study included at least 1 control for comparison. ResultsThe search identified 2094 studies, with 234 reviewed at full-text level, and 49 included in the analysis (20 adult, 19 pediatric, 7 pediatric and adult, and 3 not stated). Most (26 of 49) were published after 2014. Thirty-five studies included healthy controls, 9 analyzed atopic controls, and 29 compared samples from patients with active and inactive EoE. Minimally invasive biomarkers were obtained from peripheral blood (n = 41 studies), sponge or string samples (n = 3), oral or throat swab secretions (n = 2), breath condensate (n = 2), stool (n = 2), and urine (n = 2). The most commonly reported biomarkers were peripheral blood eosinophils (n = 16), blood and string eosinophil granule proteins (n = 14), and eosinophil surface or intracellular markers (n = 12). EoE biomarkers distinguished active EoE from healthy controls in 23 studies, atopic controls in 2 studies, and inactive EoE controls in 20 studies. ConclusionSeveral promising minimally invasive biomarkers for EoE have emerged; however, few are able to differentiate EoE from other atopic diseases.

Sex differences in function and structure of the quadriceps muscle in chronic obstructive pulmonary disease patients.

Chronic obstructive pulmonary disease (COPD) is a complex disorder with extrapulmonary manifestations. Even though there is some knowledge regarding sex differences in the lung disease, little is known about extrapulmonary manifestations. Our aim was to analyze the specific profile of muscle dysfunction, structure, and biology in COPD women. Twenty-one women and 19 men with stable COPD as well as 15 controls were included. Nutritional status, physical activity, lung and muscle function, exercise capacity, and quality of life were assessed. In addition, blood, breath condensate, and quadriceps muscle samples were tested for inflammatory markers. Moreover, fiber phenotype, signs of damage-regeneration, and the expression of key genes linked to myogenesis and inflammation were assessed in the muscle. Inflammatory markers were increased in all body compartments but no correlation was found among them. Muscle dysfunction was present in both COPD groups but was more marked in women. The opposite occurred with the increase in the percentage of type II fibers that was lower in women despite a similar level of airway obstruction as in men. Female COPD also showed higher signs of muscle damage than COPD men who, in contrast, exhibited slightly higher signs of regeneration. We conclude that sex influences muscle phenotype and function in COPD.

Hydrogen peroxide in exhaled air: a source of error, a paradox and its resolution.

The concentration of hydrogen peroxide (H2O2) in exhaled air has been reported to be elevated in asthma and chronic obstructive pulmonary disease (COPD), but results are inconsistent and difficult to reproduce. As H2O2 occurs in ambient air, we examined its association with exhaled H2O2 in human subjects.Exhaled breath condensate (EBC) of 12 COPD patients and nine healthy control subjects was collected either with an inhalation filter (efficiency 81%) or without. Ambient air condensate (AAC) was collected in parallel and samples were analysed for H2O2. Additionally, ambient H2O2 was recorded by an atmospheric measuring device (online fluorometric measurement).H2O2 concentration in AAC was significantly higher (p<0.001) than in EBC. AAC variations were concordant with the data from the atmospheric measuring instrument. In both subjects' groups, the inhalation filter reduced H2O2 values (p<0.01). Despite generally low levels in exhaled air, analysis by a mathematical model revealed a contribution from endogenous H2O2 production.The low H2O2 levels in exhaled air are explained by the reconditioning of H2O2-containing inhaled air in the airways. Inhaled H2O2 may be one factor in the heterogeneity and limited reproducibility of study results. A valid determination of endogenous H2O2 production requires inhalation filters.

Assessment of terbium (III) as a luminescent probe for the detection of tuberculosis biomarkers

A detection method for nicotinic acid, a specific metabolite marker of Mycobacterium tuberculosis present in cultures and patients' breath, is studied in complex solutions containing other metabolites and in biological media such as urine, saliva and breath condensate. The method is based on the analysis of the luminescence increase of Tb3+ complexes in the presence of nicotinic acid due to the energy transfer from the excited ligand to the lanthanide ion. It is shown that other potential markers found in M. tuberculosis culture supernatant, such as methyl phenylacetate, p-methyl anisate, methyl nicotinate and 2-methoxy biphenyl, can interfere with nicotinic acid via a competitive absorption of the excitation photons. A new strategy to circumvent these interferences is proposed with an upstream trapping of volatile markers preceding the detection of nicotinic acid in the liquid phase via the luminescence of Tb3+ complexes. The cost of the method is evaluated and compared with the Xpert MTB/RIF test endorsed by the World Health Organization.

Cytokines in asthma: effects on human pulmonary fibroblasts (835.8)

In the asthmatic patient, CD4+ T lymphocytes elevate chemokines in airway fluids and blood. This study assayed effects of serum from asthmatic adults on the metabolism of healthy human lung fibroblasts in culture, comparing effects to those seen with sera from lung‐healthy volunteers. WI38 human lung fibroblasts (ATCC) were cultured in MEM + 15% fetal calf serum. At assay, 1500 cells in 100 µL were added to 96‐well plates, and after attachment, media was replaced with serum‐free MEM with 15 µL asthma or control sera. After 24 hr incubation, MTT formazan cell proliferation was assayed at 570 nm. Tests were repeated 3x.MTT of 24 asthmatics averaged 1.37 ± 0.12 vs 1.28 ± 0.11 for 16 controls, p=0.03 with 3 replications. Sera with high IgE (ELISA) were compared to low by MTT values and were not different. Serum and breath condensate have recently been assayed for multiple chemokines but not for effects of these effluents on healthy lung cells. Our tests, while not identifying components demonstrate the expression of substances in asthma that raise the inflammatory response of healthy cells (measured by MTT upregulation). We showed the upregulation was significantly greater by asthmatic sera than by control sera. The use of asthma serum‐sensitized cells in culture offers high possibility of clarifying the disease of asthma and its humoral processes beyond cell‐related triggers.Grant Funding Source: Sarah Morrison Student Grant to SL

Acute effects of summer air pollution on pulmonary function and airway inflammation in healthy young women.

BackgroundExposure to air pollution has been reported to be associated with asthma exacerbation. However, little is known about the effects of air pollutant exposure in healthy people. A panel study was conducted to evaluate the acute effects of air pollutants on pulmonary function and airway inflammation in healthy subjects.MethodsExhaled breath condensate (EBC) pH, fractional concentration of exhaled nitric oxide (FeNO), and pulmonary function were measured in 21 healthy young women repeatedly for two weeks in the summer in Tokyo, Japan. The concentrations of air pollutants were obtained from the monitoring stations in the neighborhoods where the subjects lived. Statistical analyses were performed using generalized estimating equations.ResultsEBC pH decreased significantly with a 10-ppb increase in the 4-day average ozone (O3) concentration and a 10-µg/m3 increase in the 4-day average suspended particulate matter (SPM) concentration (−0.07 [95% confidence interval {CI} −0.11 to −0.03] and −0.08 [95% CI −0.12 to −0.03], respectively). Subjects with a history of rhinitis showed marked decreases in EBC pH associated with increases in O3 and SPM. The changes in forced expiratory volume in 1 second (FEV1) were also significantly associated with a 10-µg/m3 increase in the 3-day average concentration of SPM (−0.09 L [95% CI −0.17 to −0.01]). FeNO increased significantly in relation to the increase in O3 and SPM among only subjects with a history of asthma.ConclusionsOver the course of the study, EBC became significantly acidic with increases in O3 and SPM concentrations. Furthermore, higher SPM concentrations were associated with decreased FEV1. Subjects with a history of rhinitis or asthma are considered to be more susceptible to air pollutants.