Exhaled Breath Condensate Levels Research Articles

Intranasal PAMAM-G3 scavenges cell-free DNA attenuating the allergic airway inflammation

Allergic airway inflammation (AAI), including allergic rhinitis (AR) and allergic asthma, is driven by epithelial barrier dysfunction and type 2 inflammation. However, the underlying mechanism remains uncertain and available treatments are constrained. Consequently, we aim to explore the role of cell-free DNA (cfDNA) in AAI and assess the potential alleviating effects of cationic polymers (CPs) through cfDNA elimination. Levels of cfDNA were evaluated in AR patients, allergen-stimulated human bronchial epithelium (BEAS-2B cells) and primary human nasal epithelium from both AR and healthy control (HC), and AAI murine model. Polyamidoamine dendrimers-generation 3 (PAMAM-G3), a classic type of cationic polymers, were applied to investigate whether the clearance of cfDNA could ameliorate airway epithelial dysfunction and inhibit AAI. The levels of cfDNA in the plasma and nasal secretion from AR were higher than those from HC (P < 0.05). Additionally, cfDNA levels in the exhaled breath condensate (EBC) were positively correlated with Interleukin (IL)-5 levels in EBC (R = 0.4191, P = 0.0001). Plasma cfDNA levels negatively correlated with the duration of allergen immunotherapy treatment (R = −0.4297, P = 0.006). Allergen stimulated cfDNA secretion in vitro (P < 0.001) and in vivo (P < 0.0001), which could be effectively scavenged with PAMAM-G3. The application of PAMAM-G3 inhibited epithelial barrier dysfunction in vitro and attenuated the development of AAI in vivo. This study elucidates that cfDNA, a promising biomarker for monitoring disease severity, aggravates AAI and the application of intranasal PAMAM-G3 could potentially be a novel therapeutic intervention for AAI.Allergen stimulates the secretion of cell-free DNA (cfDNA) in both human and mouse airway. Intranasal polyamidoamine dendrimers-generation 3 (PAMAM-G3) scavenges cfDNA and alleviates allergic airway inflammation.

Digital image colorimetry for determination of ethanol in exhaled breath condensate.

Aim: This study aimed to develop a colorimetric approach for quantifying ethanol using smartphone image analysis. Method: This research presents a straightforward smartphone-based colorimetric sensor that efficiently measures ethanol levels in exhaled breath condensate (EBC) samples. The process involved changing the acidic dichromate color in an ethanolic solution, followed by image analysis. Results: The results showed that this method was able to estimate ethanol concentrations in the range of 300-1500 and 1600-8000μg ml-1 in EBC. Conclusion: This study was a follow-up study on the previous work published for the determination of ethanol in EBC samples and highlights the potential benefits of using digital images and smartphone applications for ethanol determination in biological samples.

Advances in proteomics methods for the analysis of exhaled breath condensate.

The analysis of exhaled breath condensate (EBC) demonstrates a promising avenue of minimally invasive biopsies for diagnostics. EBC is obtained by cooling exhaled air and collecting the condensation to be utilized for downstream analysis using various analytical methods. The aqueous phase of breath contains a large variety of miscible small compounds including polar electrolytes, amino acids, cytokines, chemokines, peptides, small proteins, metabolites, nucleic acids, and lipids/eicosanoids-however, these analytes are typically present at minuscule levels in EBC, posing a considerable technical challenge. Along with recent improvements in devices for breath collection, the sensitivity and resolution of liquid chromatography coupled to online mass spectrometry-based proteomics has attained subfemtomole sensitivity, vastly enhancing the quality of EBC sample analysis. As a result, proteomics analysis of EBC has been expanding the field of breath biomarker research. We present an au courant overview of the achievements in proteomics of EBC, the advancement of EBC collection devices, and the current and future applications for EBC biomarker analysis.

Changes and clinical significance of multiple cytokines in exhaled breath condensate in patients with severe inhalation injury

To investigate the changes and clinical significance of multiple cytokine levels in exhaled breath condensate (EBC) in patients undergoing tracheotomy with severe inhalation injury. A prospective study was conducted. A total of 32 patients with severe burn combined with severe inhalation injury admitted to the department of burns and plastic surgery of Affiliated Suzhou Hospital of Nanjing Medical University from May 2021 to August 2022 were enrolled. Twenty healthy volunteers from the same period were served as controls. EBC of patients at 12 hours after burn and the samples of healthy controls were collected. The levels of 27 cytokines in EBC, including tumor necrosis factor-α (TNF-α) and interleukins (IL-1β, IL-6, IL-8, IL-10, and IL-17), were determined by liquid phase chip technology. Meanwhile, plasma of patients at 12 hours after burn and the plasma of volunteers were collected, and the levels of inflammatory cytokines were detected by liquid chip technology, and the differences between the levels in plasma and those in EBC were analyzed. Plasma and EBC of patients with aspiration injury were collected at 12 hours and 3, 7, 14 and 21 days after burn, and TNF-α levels were determined by enzyme-linked immunosorbent assay (ELISA). Finally, 32 patients were enrolled, and the total burned area was (40±16)% of total body surface area (TBSA). The time of admission was (4.2±2.3) hours after injury. (1) Twenty-seven cytokines in EBC: 18 kinds of cytokines including macrophage inflammatory protein-1β (MIP-1β), IL-6, IL-5, IL-2, IL-1β, IL-8, IL-10, IL-15, IL-9, interferon-γ (IFN-γ), IL-1 receptor antagonist (IL-1ra), TNF-α, chemotactic factor for eosinophil (Eotaxin), basic fibroblast growth factor (bFGF), platelet derived growth factor-BB (PDGF-BB), interferon-inducible protein-10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), granulocyte colony-stimulating factor (G-CSF) were significantly increased in patients with severe aspiration injury compared with health controls. Eotaxin was not detected in EBC of healthy controls. Five cytokines, granulocyte-macrophage colony-stimulating factor (GM-CSF), chemokine ligand 5 (CCL5/RANTES), IL-13, IL-4 and MIP-1α, were not detected in EBC of severe inhalation injury patients and healthy controls. Vascular endothelial growth factor (VEGF) and IL-12 p70 in EBC of severe aspiration injury patients were slightly decreased as compared with healthy controls, while IL-7 and IL-17 were slightly increased, but the differences were not statistically significant. (2) Six inflammatory cytokines in plasma: the levels of IL-6 and IL-8 in the severe aspiration injury group were significantly increased as compared with healthy controls [IL-6 (ng/L): 18.51 (10.87, 26.21) vs. 0.22 (0.10, 0.36), IL-8 (ng/L): 10.75 (8.58, 18.79) vs. 1.06 (0.81, 2.14), both P < 0.01]. The plasma levels of TNF-α, IL-1β and IL-10 were slightly increased in patients with severe aspiration injury as compared with healthy controls, and IL-17 was slightly decreased, but the difference was not statistically significant. In the EBC collected during the same period, five inflammatory cytokines, including TNF-α, IL-1β, IL-6, IL-8 and IL-10, in patients with severe inhalation injury were significantly increased as compared with healthy controls [TNF-α (ng/L): 16.42 (12.57, 19.21) vs. 7.34 (6.11, 8.69), IL-1β (ng/L): 15.57 (10.53, 20.25) vs. 0.99 (0.67, 1.41), IL-6 (ng/L): 13.36 (9.76, 16.54) vs. 0.70 (0.42, 0.85), IL-8 (ng/L): 1 059.29 (906.91, 1 462.37) vs. 10.36 (8.40, 12.37), IL-10 (ng/L): 2.69 (1.54, 3.33) vs. 1.54 (1.18, 2.06), all P < 0.05]. (3) Dynamic changes of TNF-α in plasma and EBC: the level of TNF-α in EBC of patients with severe aspiration injury was lower than that in plasma. Plasma TNF-α level was increased gradually with the extension of time after injury, and was significantly higher than that of healthy controls on day 3 [ng/L: 30.38 (24.32, 39.19) vs. 22.94 (17.15, 30.74), P < 0.05], and reached the peak on day 14, then fell back. The level of TNF-α in EBC at 12 hours after injury was significantly higher than that in healthy controls [ng/L: 15.34 (11.75, 18.14) vs. 6.99 (6.53, 7.84), P < 0.01], and reached the peak on 3 days after injury, and then gradually decreased. There are changes in the expression of multiple cytokines in EBC of patients with severe inhalation injury, and the changes of many inflammatory cytokines including TNF-α are more sensitive than those in plasma, which can be used to monitor and evaluate the condition of patients with inhalation injury.

IL-6 and TGF-β as markers of air-blood barrier damage in children with acute lymphoblastic leukemia: сlinical and prognostic aspects

Background. Damage markers of blood-air barrier are important for studding pathological process in lungs in children with acute lymphoblastic leukemia (ALL).&#x0D; Purpose is to analyses pulmonary complications and to assess IL-6 and TGF-β levels in the exhaled breath condensate (EBC) in children with ALL and its prognostic value.&#x0D; Materials and Methods. 40 children with ALL aged 6–17 years were examined. 1st group included newly diagnosed ALL (n = 18). 2nd group involved ALL survivors who had completed course of ALL IC BFM 2009 protocols (n = 22). The control group consisted of 15 healthy children. The levels of IL-6 and TGF- β in the EBC were analyzed by ELISA.&#x0D; Results and discussion. Pulmonary complications presented in 82.5% of children with ALL during chemotherapy and in 15.8% of ALL survivors. IL-6 and TGF-β levels in EBC were significantly higher in both ALL groups than control: IL-6 p1-C = 0,000001; p2-C = 0,000000; TGF-β p1-C = 0.000014; p2-C = 0.009364. 1st group had higher levels of IL-6 and TGF-β in the EBC than 2nd group: IL-6 p1-2 = 0,000000; TGF-β p1-2 = 0.000141. There was a positive correlation between IL-6 and TGF-β levels (r = 0.681176, p = 0.000001). According to ROC analysis, IL-6 level in EBC collected during Protocol 1 &gt; 47.64 pg/ml can be prognostic for pulmonary complications during chemotherapy (AUC 0.875; Sensitivity 75.0%; Specificity 100,0%). Level of IL-6 &gt; 49.96 pg/ml can predict pneumonia during chemotherapy (AUC 0,883; Sensitivity 100.00%; Specificity 81.82%). IL-6 level after the total course of chemotherapy &gt; 23.64 pg/ml can predict pulmonary complications in ALL survivors (AUC 0.819; Sensitivity 75.00%; Specificity 81.82%). TGF-β level in EBC after the completion of chemotherapy &gt; 19.93 pg/ml can be prognostic for pulmonary complications in ALL survivors (AUC 0.896; Sensitivity 100.00%; Specificity 77.78%).&#x0D; Conclusions. IL-6 and TGF-β levels in EBC can be prognostic for pulmonary complications in children with ALL.

Exhaled phospholipids as a prognostic factor of pulmonary complications in children with acute lymphoblastic leukemia

Introduction. Pulmonary complications are common in children with acute lymphoblastic leukemia (ALL). The assessment of phospholipids (PL) in the exhaled breath condensate can provide more information about pathological processes in the lungs in children with ALL. Purpose - to assess the level of PL in the exhaled breath condensate (EBC) in children with ALL and its prognostic value. Materials and methods. 40 children with ALL aged 6-17 years were examined. 1st group included newly diagnosed children with ALL (n=18). 2nd group involved ALL survivors, who had completed the total course of chemotherapy (n=22). The control (С) group consisted of 15 healthy children. The levels of PL in the EBC were investigated by spectrophotometric thin-layer chromatography using an SPh 46 spectrophotometer. Results. The frequency of pulmonary complication was 82.5% during chemotherapy protocols and 18.4% in ALL survivals. The statistically significant increase in the level of phospholipids in 1st (150.75 (137.62; 158.45) mmol/l) and 2nd (130.12 (120.59; 138.34) mmol/l) ALL groups compared with the group C (54.80 (48.30; 60.80) mmol/l) has been detected (p1-C=0.0000; p2-C=0.0000). Children of the 1st group had significantly higher levels of PL in the EBC than children of the 2nd group (p1-2=0.002911). PL level in EBC collected during induction phase of chemotherapy &gt;132.15 mmol/l can be prognostic for the development of acute pulmonary complications (Sensitivity 93.75%; Specificity 100%). PL level in EBC collected after a complete course of chemotherapy &gt;133.28 mmol/l can be predictive for persistent pulmonary complications (Sensitivity 100.00%; Specificity 83.33%). Conclusions. PL level in EBC can be prognostic for the development of pulmonary complications, both during chemotherapy and in long-term remission after completed chemotherapy course. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

Sex-specific association of exposure to air pollutants and Nrf2 gene expression and inflammatory biomarkers in exhaled breath of healthy adolescents

Studies investigating the nuclear factor erythroid 2-related factor 2 (Nrf2) expression levels in the respiratory system of healthy subjects are scarce. Moreover, separate studies on the health-related outcomes of air pollution for each sex are limited. The current panel study investigated sex-specific Nrf2 expression levels and related oxidative stress and inflammatory responses among healthy adolescents exposed to PM2.5, PM10, O3, and PM2.5-bounded metals in a high traffic region. Forty-nine healthy nonsmoking subjects participated in the study for five consecutive months (Nov. 2019 to Feb. 2020). Each subject was asked to provide 1 mL of exhaled breath condensate (EBC). Data were analyzed using linear mixed-effects models. The results showed that PM10, PM2.5, O3, and PM2.5-bounded metals were negatively linked to Nrf2 expression level in EBC of females with −58.3% (95% CI: 79.5, −15.4), −32.1% (95% CI: −50.3, −7.1), −76.2% (95% CI: −92.6, −23.9), and −1.9 (95% CI: −3.4, −0.4), respectively. While our results presented no significant association between the studied pollutants and Nrf2 gene expression in males, significant associations were observed between the pollutants and total nitric oxide (NOx), interleukins 6 (IL-6), and tumor necrosis factor-alpha (TNF-α) in the EBC of females. In the case of males, only EBC cytokines showed a significant association with air pollutants. Overall, this study suggests that exposure to ambient air pollutants may affect the respiratory system with biologically different mechanisms in males and females. PM2.5 concentration had a positive correlation with exhaled TNF-α and IL6 values in females while positive correlation with TNF-α and negative correlation with IL6 values in males. O3 had a negative correlation with TNF-α in males.

Characterization of the elemental and particle load of patient exhaled breath condensate and comparison with pulmonary lavages

In the field of biomonitoring, exhaled breath condensate (EBC) is described as a potentially useful matrix for assessing inhalation exposure biomarkers in a non-invasive way. However, it is still unclear to what extent EBC is representative of the deep lung. To address this knowledge gap, EBC, bronchial washes (BWs), and bronchoalveolar lavages (BALs) were collected from 82 patients suffering from interstitial lung diseases (ILDs). The particulate contents and elemental composition of EBC, BW, and BAL were then compared in the same patients. The size distribution of particles in EBC was assessed with dynamic light scattering while inductively coupled plasma mass spectrometry was used to quantify its elemental composition. In addition, transmission electron microscopy coupled with energy dispersive x-ray spectrometry were used to further characterize samples of interest. EBC was found to be representative of both the sub-micron and nano-sized particle fractions of BAL and BW, with lower overall levels of elements in EBC than in BW and BAL. Silicon (Si) was the main component for all respiratory matrices with median levels of 2525 µg l−1, 5643 µg l−1 and 5169 µg l−1 in the nano/ion fractions of EBC, BAL and BW, respectively. Moreover, Si levels in EBC from patients in this study were elevated compared to the levels reported in the literature for healthy subjects. Interestingly, Si levels in the EBC of ILD patients were inversely related to those in BAL and BW. In conclusion, the particulate content of EBC is associated with the lung particle burden and potentially correlates with pathologies, rendering it a relevant biomonitoring technique for the occupational and clinical fields.

The miRNA-24, miRNA-21 expressions and matrix metalloproteinase-7 level in exhaled breath condensate of children with primary spontaneous pneumothorax

Bullous lung diseases may cause primary spontaneous pneumothorax (PSP) in children. The microRNAs (miRNAs) are non-coding RNAs that participate in regulation of inflammation and cancer. We hypothesized that children with bullous lung disease and PSP may have altered miRNA expressions in their exhaled breath condensates (EBCs). Therefore, a prospective study was performed to evaluate the miRNA-24 and 21 expression, and the matrix metalloproteinase-7 (MMP-7) levels in EBC of children with PSP. Children with PSP were evaluated for age, gender, clinical features and results of surgical treatment. EBC samples (500–1000 ml) were collected to evaluate the miRNA-21, 24 expressions, and MMP-7, and tissue-inhibitor-MMP-1 (TIMP-1) levels. miRNA expressions and MMP levels of patients were compared with healthy controls (control group (CG), n = 12). Subjects (n = 16) with a mean age of 15 years (10–19 years), and a male-to-female ratio of 14:2 were enrolled in this study. The most common presenting symptom was sudden chest pain (n = 14). In 62.5% of the cases an underlying bullous lung disease were detected. During an average of 16.6 months (1–60 months) follow up period, four subjects relapsed. The mean MMP-7 (1.74–1.57 ng ml−1), and TIMP-1 (1.92–1.84 ng ml−1) levels were similar between both groups (p > 0.05). miRNA-24 expression was significantly decreased in the PSP group, when compared to the CG (0.16–1 2−ΔΔCT, p < 0.05). In addition, the miRNA-21 expression was not different between the two groups (p > 0.05). In conclusion, the miRNA-24 levels were significantly decreased in children with PSP. Taken together, children with PSP, especially those with bullous disease, should be closely monitored in the long-term period.

Metabolites of L-ARG in Exhaled Breath Condensate and Serum Are Not Biomarkers of Bronchial Asthma in Children.

(1) Background: L-arginine (L-ARG) and its metabolites are involved in some aspects of asthma pathogenesis (airway inflammation, oxidative stress, bronchial responsiveness, collagen deposition). Published data indicate that lungs are a critical organ for the regulation of L-ARG metabolism and that alterations in L-ARG metabolism may be significant for asthma. The aim of this study was to assess the levels of L-ARG and its metabolites in pediatric patients with asthma in serum and exhaled breath condensate (EBC) by mass spectrometric analysis and compare them with non-asthmatic children. (2) Methods: Sixty-five children (37 pediatric patients with bronchial asthma and 28 healthy control subjects) aged 6–17 participated in the study. All participants underwent a clinical visit, lung tests, allergy tests with common aeroallergens, and serum and EBC collection. The levels of biomarkers were determined in both serum and EBC. Analytical chromatography was conducted using an Acquity UPLC system equipped with a cooled autosampler and an Acquity HSS T3 column. Mass spectrometric analysis was conducted using the Xevo G2 QTOF MS with electrospray ionization (ESI) in positive ion mode. (3) Results: Asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) levels in serum and EBC did not differ significantly in asthmatic children and healthy control subjects. We found no correlation between forced expiratory volume in one second (FEV1) and L-ARG and its metabolites, as well as between interleukin-4 (IL-4) serum level and L-ARG and its metabolites. Concentrations of ADMA, SDMA, citrulline (CIT), and ornithine (ORN) were higher in serum than EBC in asthmatics and non-asthmatics. By contrast, concentrations of dimethylarginine (DMA) were higher in EBC than serum. ADMA/L-ARG, SDMA/L-ARG, and DMA/L-ARG ratios were significantly higher in EBC than in serum in asthmatics and in non-asthmatics. (4) Conclusions: Serum and EBC concentrations of L-ARG and its metabolites were not an indicator of pediatric bronchial asthma in our study.

Prospective Exploratory Study of the Relationship Between Radiation Pneumonitis and TGF-β1 in Exhaled Breath Condensate.

We conducted a prospective exploratory study to investigate the relationship between radiation pneumonitis (RP) and transforming growth factor-β1 (TGF-β1) in exhaled breath condensate (EBC). The inclusion criteria were: patients who 1) received thoracic radiotherapy (RT) for lung cancer, 2) were aged ≥20 years, and 3) provided written informed consent. EBC was collected before and 1 month after RT. TGF-β1 levels in EBC were measured using an enzyme-linked immunosorbent assay. We evaluated RP using the Common Terminology Criteria for Adverse Events v4 and analyzed the relationship between grade (G) 2 RP and TGF-β1 levels in EBC. Ten patients were enrolled [median age, 75 years (range=60-81 years)], and none of them had interstitial lung disease. Conventional fractionation, accelerated hyperfractionation, hypofractionation, and stereotactic ablative fractionation were used in four, one, two, and three patients, respectively. G1 and G2 RP were observed in five patients each; no G3-G5 RP occurred. The median TGF-β1 levels in EBC before and 1 month after RT were 79.1 pg/ml (0.1-563.7 pg/ml) and 286.9 pg/ml (33.7-661.3 pg/ml), respectively. Of the seven patients with increased TGF-β1 levels in EBC 1 month after RT than before RT, five (71%) experienced G2 RP, whereas the remaining three patients with decreased TGF-β1 levels had G1 RP (p=0.083, one-sided Fisher's exact test). Increased TGF-β1 levels in EBC 1 month after RT might be promising for the detection of G2 RP.

Biosensor-Enabled Multiplexed On-Site Therapeutic Drug Monitoring of Antibiotics.

Personalized antibiotherapy ensures that the antibiotic concentration remains in the optimal therapeutic window to maximize efficacy, minimize side effects, and avoid the emergence of drug resistance due to insufficient dosing. However, such individualized schemes need frequent sampling to tailor the blood antibiotic concentrations. To optimally integrate therapeutic drug monitoring (TDM) into the clinical workflow, antibiotic levels can either be measured in blood using point-of-care testing (POCT), or can rely on noninvasive sampling. Here, a versatile biosensor with an antibody-free assay for on-site TDM is presented. The platform is evaluated with an animal study, where antibiotic concentrations are quantified in different matrices including whole blood, plasma, urine, saliva, and exhaled breath condensate (EBC). The clearance and the temporal evaluation of antibiotic levels in EBC and plasma are demonstrated. Influence of matrix effects on measured drug concentrations is determined by comparing the plasma levels with those in noninvasive samples. The system's potential for blood-based POCT is further illustrated by tracking ß-lactam concentrations in untreated blood samples. Finally, multiplexing capabilities are explored successfully for multianalyte/sample analysis. By enabling a rapid, low-cost, sample-independent, and multiplexed on-site TDM, this system can shift the paradigm of "one-size-fits-all" strategy.

Inhaled corticosteroids’ effects on biomarkers in exhaled breath condensate and blood in patients newly diagnosed with asthma who smoke

Objective Exposure to cigarette smoke complicates the treatment and management of asthma through a variety of inflammatory effects. This study aimed to investigate the differences between newly diagnosed cases of asthma in smokers and nonsmokers in terms of localized and systemic biomarkers following treatment with inhaled corticosteroids (ICS) or ICS in combination with a long-acting β2 agonist (LABA). Methods Specimens of exhaled breath condensate (EBC) from newly diagnosed patients with asthma were used to quantify inflammation in the airways, while blood samples were used to assess systemic inflammation. In both samples, the levels of IL-6, LTB4, LTD4, and 8-isoprostane were measured and these were repeated after 3 months of treatment with ICS or ICS + LABA. Results Of the 20 patients, 10 (50%) were nonsmokers with asthma (NSA) and 10 (50%) smokers with asthma (SA). There was no statistically significant difference in the blood or EBC levels of IL-6, LTB4, LTD4, or 8-isoprostane between the groups prior to treatment. Only the decrease in 8-isoprostane level in the EBC samples was found to be significantly greater in the NSA group after treatment (for smokers, the change was 2.91 ± 23.22, while for nonsmokers it was −22.72 ± 33.12, p = 0.022). Post-treatment asthma control was significantly better in the NSA group (p = 0.033). Conclusion Monitoring the alterations in 8-isoprostane levels in EBC in patients with asthma who smoke may be helpful in deciding on therapeutic management and switching treatments. Asthma control was better in nonsmokers than in smokers.

Clinical Utility of microRNAs in Exhaled Breath Condensate as Biomarkers for Lung Cancer.

This study represents a novel proof of concept of the clinical utility of miRNAs from exhaled breath condensate (EBC) as biomarkers of lung cancer (LC). Genome-wide miRNA profiling and machine learning analysis were performed on EBC from 21 healthy volunteers and 21 LC patients. The levels of 12 miRNAs were significantly altered in EBC from LC patients where a specific signature of miR-4507, miR-6777-5p and miR-451a distinguished these patients with high accuracy. Besides, a distinctive miRNA profile between LC adenocarcinoma and squamous cell carcinoma was observed, where a combined panel of miR-4529-3p, miR-8075 and miR-7704 enabling discrimination between them. EBC levels of miR-6777-5p, 6780a-5p and miR-877-5p predicted clinical outcome at 500 days. Two additional miRNA signatures were also associated with other clinical features such as stage and invasion status. Dysregulated EBC miRNAs showed potential target genes related to LC pathogenesis, including CDKN2B, PTEN, TP53, BCL2, KRAS and EGFR. We conclude that EBC miRNAs might allow the identification, stratification and monitorization of LC, which could lead to the development of precision medicine in this and other respiratory diseases.

Effects of continuous positive airway pressure on resolvin and matrix metalloproteinase-9 in patients with obstructive sleep apnea

PurposeResolvin is a checkpoint controller in inflammation. Matrix metalloproteinase-9 (MMP-9) is an airway remodeling regulator. We evaluated the levels of resolvin and MMP-9 protein in the serum and exhaled breath condensate (EBC) before and after continuous positive airway pressure (CPAP) treatment. MethodWe enrolled 20 non-OSA snorers and 40 patients with moderate to severe OSA scheduled for CPAP treatment. ELISA was used to assess resolvin and MMP-9 levels in the serum and EBC. All patients underwent sleep assessment at baseline and 3 months after CPAP. ResultsThere was no between-group difference; moreover, there were no differences in the pre- and post-treatment serum levels of resolvin and MMP-9 in patients with OSA. Compared with non-OSA snorers, patients with OSA had lower resolvin and higher MMP-9 levels in the EBC. After CPAP treatment, the EBC levels of resolvin and MMP-9 in patients with OSA returned to normal. ConclusionsSuccessful OSA treatment by CPAP can normalize EBC levels of resolvin and MMP-9.

MicroRNA Levels in Exhaled Breath Condensate of Patients with Esophageal Atresia.

MicroRNAs (miRNAs) are noncoding RNAs that play an important role in the regulation of inflammation and have not been evaluated in exhaled breath condensates (EBC) of patients with esophageal atresia and tracheoesophageal fistula (EA-TEF). It is aimed to evaluate the levels of miRNA-21 and miRNA-24 in EBC of patients with EA-TEF. Patients who received surgery for EA-TEF (EA) were assessed for age, sex, types of anomaly, surgical treatments, and respiratory problems. A 500-1000 mL of EBC was obtained from each participant with EcoScreen. The levels of miRNA-21 and miRNA-24 in the EBC were analyzed by real-time polymerase chain reaction and compared between the EA group and the control group consisting of healthy children with no history of respiratory problems (n= 17). The levels of miRNAs in relation to respiratory problems and gastroesophageal reflux (GER) were also assessed. A total of 19 patients were enrolled in the EA group with a mean age of 7.8 ± 3.2 years and a male-to-female ratio of 10:9 EA cases had significantly lower levels of miRNA-21 (P< 0.05) compared to that in control group. The miRNA-24 levels did not differ between groups (P> 0.05). EA patients with positive pH testing for GER (n= 6) and fundoplication (n= 6) had higher levels of miRNA-21 than those with normal pH testing and without fundoplication, respectively (n= 13, P< 0.05). The levels of miRNA-21 and miRNA-24 did not differ between patients with and without proton pump inhibitor treatment (P> 0.05). The lower levels of miRNA-21 in the EBC of EA patients suggest a hyperreactive airway problem, which may be associated with GER and its surgical treatment.

Pathways in the Pathophysiology of Coronavirus 19 Lung Disease Accessible to Prevention and Treatment.

Background: In COVID 19 related lung disease, which is a leading cause of death from this disease, cytokines like tumor necrosis factor-alpha (TNF alpha) may be pivotal in the pathogenesis. TNF alpha reduces fluid absorption due to impairment of sodium and chloride transport required for building an osmotic gradient across epithelial cells, which in the airways maintains airway surface liquid helping to keep airways open and enabling bacterial clearance and aids water absorption from the alveolar spaces. TNF alpha can, through Rho-kinase, disintegrate the endothelial and epithelial cytoskeleton, and thus break up intercellular tight junctional proteins, breaching the intercellular barrier, which prevents flooding of the interstitial and alveolar spaces with fluid.Hypotheses: (1) Preservation and restoration of airway and alveolar epithelial sodium and chloride transport and the cytoskeleton dependent integrity of the cell barriers within the lung can prevent and treat COVID 19 lung disease. (2) TNF alpha is the key mediator of pulmonary edema in COVID 19 lung disease.Confirmation of hypothesis and implications: The role of a reduction in the function of epithelial sodium and chloride transport could with regards to chloride transport be tested by analysis of chloride levels in exhaled breath condensate and levels correlated with TNF alpha concentrations. Reduced levels would indicate a reduction of the function of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel and a correlation with TNF alpha levels indicative of its involvement. Anti-TNF alpha treatment with antibodies is already available and needs to be tested in randomized controlled trials of COVID 19 lung disease. TNF alpha levels could also be reduced by statins, aspirin, and curcumin. Chloride transport could be facilitated by CFTR activators, including curcumin and phosphodiesterase-5 inhibitors. Sodium and chloride transport could be further regulated to prevent accumulation of alveolar fluid by use of Na(+)/K(+)/2Cl(−) cotransporter type 1 inhibitors, which have been associated with improved outcome in adults ventilated for acute respiratory distress syndrome (ARDS) in randomized controlled trials. Primary prevention of coronavirus infection and TNF alpha release in response to it could be improved by induction of antimicrobial peptides LL-37 and human beta defensin-2 and reduction of TNF alpha production by vitamin D prophylaxis for the population as a whole.

Relevance between clinical status and exhaled molecules related to neutrophilic inflammation in pediatric cystic fibrosis

Introduction: Cystic fibrosis (CF) is characterized with chronic inflammation with neutrophil and related cytokines in airway secretions. We aimed to measure the levels of neutrophil related inflammatory markers as nitric oxide, IL-8, IL-17, leukotriene B4 and neutrophil elastase as well as e-cadherin in exhaled breath condensate (EBC), and to determine their relation with clinical findings. Methods: We consecutively enrolled cystic fibrosis patients into our clinics between the age of six and eighteen years who could cooperate for exhaled breath condensate to this case-control study (n = 30). The age and sex matched control group (n = 26) was enrolled. Spirometry was performed during the stable period and EBC samples were obtained for measurement of the markers. Results: The mean age of the subjects enrolled was 12.1(4.2) years and 40% were positive for P.Aeruginosa in sputum. Subjects who had P.Aeruginosa in sputum cultures had significantly lower FEV1, FVC and FEF 25/75 values compared to the ones without P.Aeruginosa (p = 0.002, p = 0.002 and p = 0.005 respectively). EBC neutrophil elastase levels were significantly higher in the CF patients compared to non-CF controls (3.11 ± 4.71 versus 0.90 ± 2.68, p = 0.04). Nitric oxide, IL-17, IL-8, e-cadherin, neutrophil elastase or leukotriene B4 levels in EBC of CF patients were not related to P.Aeruginosa s infection, FEV1 levels or hospital admission in the last year. Conclusion: In our study, neutrophil elastase levels in EBC are higher in CF patients compared to non-CF controls. This is independent of acute infection and is evidence to the persistence of neutrophilic lung injury. However, EBC NO, IL-8, IL-17, e-cadherin, neutrophil elastase and leukotriene B4 levels as inflammatory markers, are not correlated with disease progression or clinical findings.

Cigarette-related cadmium and environmental pollution exposure are reflected in airway ultrafine particle content.

IntroductionParticulate matter (PM) and cigarette-related cadmium exposure increases inflammation and smokers' susceptibility to developing lung diseases. The majority of inhaled metals are attached to the surface of ultrafine particles (UFPs). A low inhaled UFP content in exhaled breath condensate (EBC) reflects a high inflammatory status of airways.MethodsEBC was collected from 58 COPD patients and 40 healthy smokers and nonsmokers. Participants underwent spirometry, diffusion capacity, EBC and blood sampling. Environmental pollution data were collected from monitoring stations. UFPs were measured in EBC and serum, and cadmium content was quantified.ResultsSubjects with low UFP concentrations in EBC (<0.18×108·mL−1) had been exposed to higher long-term PM2.5 levels versus subjects with high UFP concentrations in EBC (>0.18×108·mL−1) (21.9 µg·m−3 versus 17.4 µg·m−3, p≤0.001). Long-term PM2.5 exposure levels correlated negatively with UFP concentrations in EBC and positively with UFP concentrations in serum (r=−0.54, p≤0.001 and r=0.23, p=0.04, respectively). Healthy smokers had higher cadmium levels in EBC versus healthy nonsmokers and COPD patients (25.2 ppm versus 23.7 ppm and 23.3 ppm, p=0.02 and p=0.002, respectively). Subjects with low UFP concentrations in EBC also had low cadmium levels in EBC versus subjects with high UFP levels (22.8 ppm versus 24.2 ppm, p=0.004)ConclusionsLow UFP concentration in EBC is an indicator of high-level PM exposure. High cadmium levels in EBC among smokers and the association between cadmium and UFP content in EBC among COPD patients indicate cadmium lung toxicity.

Significance of vascular endothelium growth factor testing in exhaled breath condensate of patients with acute respiratory distress syndrome.

OBJECTIVE: We aimed to observe and investigate the clinical significance of vascular endothelium growth factor (VEGF) levels in exhaled breath condensate (EBC) from patients with acute respiratory distress syndrome (ARDS).METHODS: An improved EcoScreen condenser was used to collect EBC from 31 ARDS patients on mechanical ventilation and from 22 healthy subjects. Serum and EBC VEGF levels were analyzed with ELISA. VEGF levels in the EBC of patients with different grades of lung injuries were analyzed. The correlation between VEGF levels and clinical indicators was analyzed.RESULTS: Serum and EBC VEGF levels were linearly and positively correlated with a correlation coefficient of 0.694 ( 0.01). The VEGF level in the EBC of ARDS patients was significantly lower than that in the control group ( 0.01). The VEGF level in the EBC of the mild ARDS group was higher than that in the moderate-severe ARDS group ( 0.01). The VEGF level in the EBC of the survival group was higher than that in the mortality group. The VEGF level in the EBC of ARDS patients was positively correlated with PaO/FiO and PaO and was negatively correlated with lung injury score (LIS) and A-aDO/PaO.CONCLUSION: The changes in VEGF levels in the EBC of ARDS patients can Respiratory Medicine, reflect the severity of lung injury. Therefore, VEGF level in EBC can be used as an auxiliary index for judging the severity and prognosis of ARDS patients.