High-Yield Production of Dihydroxyacetone from Crude Glycerol in Fed-Batch Cultures of Gluconobacter oxydans.

The strain Gluconobacter oxydans LMG 1385 was used for the bioconversion of crude glycerol to dihydroxyacetone. The suitability of fed-batch cultures for the production of dihydroxyacetone was determined, and the influence of the pH of the culture medium and the initial concentration of glycerol on maximizing the concentration of dihydroxyacetone and on the yield and speed of obtaining dihydroxyacetone by bioconversion was examined. The feeding strategy of the substrate (crude glycerol) during the process was based on measuring the dissolved oxygen tension of the culture medium. The highest concentration of dihydroxyacetone PK = 175.8 g·L-1 and the highest yield YP/Sw = 94.3% were obtained when the initial concentration of crude glycerol was S0 = 70.0 g·L-1 and the pH of the substrate was maintained during the process at level 5.0.

How to Enhance the Diagnosis of Early Stages of Chronic Obstructive Pulmonary Disease (COPD)? The Role of Mobile Spirometry in COPD Screening and Diagnosis-A Systematic Review.

COPD is the third leading cause of death worldwide. Its diagnosis can be made with spirometry, which is underused due to its limited accessibility. Portable spirometry holds promise for enhancing the efficacy of COPD diagnoses. The study aimed to estimate COPD prevalence diagnosed with a portable spirometer in high-risk patients and compare it with COPD prevalence based on data from conventional, on-site spirometry. We also evaluated the strategy of a proactive approach to identify COPD in high-risk individuals. We conducted a systematic review of original studies on COPD targeted screening and diagnosis with portable and conventional spirometers selected from 8496 publications initially found in three databases: Cochrane, PubMed, and Embase. The inclusion criteria were met by 28 studies. COPD prevalence evaluated with the use of portable spirometers reached 20.27% and was lower compared to that estimated with the use of conventional spirometers (24.67%). In 11 included studies, postbronchodilator tests were performed with portable spirometers, which enabled a bedside COPD diagnosis. Portable spirometers can be successfully used in COPD targeted screening and diagnosis and thus enhance the detection of COPD at early stages.

Remotely supervised spirometry versus laboratory-based spirometry during the COVID-19 pandemic: a retrospective analysis.

BACKGROUND: The COVID-19 pandemic has constrained access to spirometry, and the inherent risk of infectious transmission during aerosol-generating procedures has necessitated the rapid development of Remotely Supervised Spirometry (RSS). This innovative approach enables patients to perform spirometry tests at home, using a mobile connected spirometer, all under the real-time supervision of a technician through an online audio or video call. METHODS: In this retrospective study, we examined the quality of RSS in comparison to conventional Laboratory-based Spirometry (LS), using the same device and technician. Our sample included 242 patients, with 129 undergoing RSS and 113 participating in LS. The RSS group comprised 51 females (39.5%) with a median age of 37 years (range: 13-76 years). The LS group included 63 females (55.8%) with a median age of 36 years (range: 12-80 years). RESULTS: When comparing the RSS group to the LS group, the percentage of accurate Forced Expiratory Volume in one second (FEV1) measurements was 78% (n = 101) vs. 86% (n = 97), p = 0.177; for Forced Vital Capacity (FVC) it was 77% (n = 99) vs. 82% (n = 93), p = 0.365; and for both FEV1 and FVC, it was 75% (n = 97) vs. 81% (n = 92), p = 0.312, respectively. CONCLUSIONS: Our findings demonstrate no significant difference in the quality of spirometry testing between RSS and LS, a result that held true across all age groups, including patients aged over 65 years. The principal advantages of remote spirometry include improved access to pulmonary function tests, reduced infectious risk to curtail disease spread, and enhanced convenience for patients.

Deep learning algorithm for visual quality assessment of the spirograms.

Objective. The quality of spirometry manoeuvres is crucial for correctly interpreting the values of spirometry parameters. A fundamental guideline for proper quality assessment is the American Thoracic Society and European Respiratory Society (ATS/ERS) Standards for spirometry, updated in 2019, which describe several start-of-test and end-of-test criteria which can be assessed automatically. However, the spirometry standards also require a visual evaluation of the spirometry curve to determine the spirograms' acceptability or usability. In this study, we present an automatic algorithm based on a convolutional neural network (CNN) for quality assessment of the spirometry curves as an alternative to manual verification performed by specialists.Approach. The algorithm for automatic assessment of spirometry measurements was created using a set of randomly selected 1998 spirograms which met all quantitative criteria defined by ATS/ERS Standards. Each spirogram was annotated as 'confirm' (remaining acceptable or usable status) or 'reject' (change the status to unacceptable) by four pulmonologists, separately for FEV1 and FVC parameters. The database was split into a training (80%) and test set (20%) for developing the CNN classification algorithm. The algorithm was optimised using a cross-validation method.Main results. The accuracy, sensitivity and specificity obtained for the algorithm were 92.6%, 93.1% and 90.0% for FEV1 and 94.1%, 95.6% and 88.3% for FVC, respectively.Significance.The algorithm provides an opportunity to significantly improve the quality of spirometry tests, especially during unsupervised spirometry. It can also serve as an additional tool in clinical trials to quickly assess the quality of a large group of tests.

A Real-World Multicenter Retrospective Observational Study on Polish Experience with Nintedanib Therapy in Patients with Idiopathic Pulmonary Fibrosis: The PolExNIB Study.

Nintedanib is a disease-modifying agent licensed for the treatment of IPF. Data on Polish experience with nintedanib in IPF are lacking. The present study aimed to describe the safety and efficacy profiles of nintedanib in a large real-world cohort of Polish patients with IPF. This was a multicenter, retrospective, observational study of IPF patients treated with nintedanib between March 2018 and October 2021. Data collection included baseline clinical characteristics, results of pulmonary function tests (PFTs), and a six-minute walk test (6MWT). Longitudinal data on PFTs, 6MWT, adverse drug reactions (ADRs), and treatment persistence were also retrieved. A total of 501 patients (70% male) with a median age of 70.9 years (IQR 65-75.7) were included in this study. Patients were followed on treatment for a median of 15 months (7-25.5). The majority of patients (66.7%) were treated with the full recommended dose of nintedanib and 33.3% of patients were treated with a reduced dose of a drug. Intermittent dose reductions or drug interruptions were needed in 20% of patients. Over up to 3 years of follow-up, pulmonary function remained largely stable with the minority experiencing disease progression. The most frequent ADRs included diarrhea (45.3%), decreased appetite (29.9%), abdominal discomfort (29.5%), weight loss (32.1%), nausea (20.8%), fatigue (19.2%), increased liver aminotransferases (15.4%), and vomiting (8.2%). A total of 203 patients (40.5%) discontinued nintedanib treatment due to diverse reasons including ADRs (10.2%), death (11.6%), disease progression (4.6%), patient's request (6.6%), and neoplastic disease (2.2%). This real-world study of a large cohort of Polish patients with IPF demonstrates that nintedanib therapy is safe, and is associated with acceptable tolerance and disease stabilization. These data support the findings of previously conducted clinical trials and observational studies on the safety and efficacy profiles of nintedanib in IPF.

Blood and Sputum Eosinophils of COPD Patients Are Differently Polarized than in Asthma.

Different eosinophil subpopulations have been identified in asthma and other eosinophilic disorders. However, there is a paucity of data on eosinophil subpopulations in patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to compare eosinophil phenotypes in blood and induced sputum in patients with COPD, asthma and controls. Stable patients with mild-to-moderate COPD (n = 15) and asthma (n = 14) with documented blood eosinophilia ≥100 cells/µL in the year prior to the study and the control group (n = 11) were included to the study. The blood and sputum eosinophil phenotypes were analyzed by flow cytometry. IL-5, IL-13, CCL5 and eotaxin-3 levels were measured in the induced sputum. The marker expression on blood eosinophils was similar among control, asthma and COPD groups. The expressions of CD125, CD193, CD14 and CD62L were higher on blood than on sputum eosinophils in all three groups. We found increased levels of CD193+ and CD66b+ sputum eosinophils from COPD patients, and an elevated level of CD11b+ sputum eosinophils in asthma compared to COPD patients. The results of our study suggest that the profile of marker expression on COPD sputum eosinophils differed from other groups, suggesting a distinct phenotype of eosinophils of COPD patients than in asthma or healthy subjects.

Metabolomic Analysis of Respiratory Epithelial Lining Fluid in Patients with Chronic Obstructive Pulmonary Disease-A Systematic Review.

Chronic obstructive pulmonary disease (COPD), as the third leading cause of death among adults, is a significant public health problem around the world. However, about 75% of smokers do not develop the disease despite the severe smoking burden. COPD is a heterogeneous disease, and several phenotypes, with differences in their clinical picture and response to treatment, have been distinguished. Metabolomic studies provide information on metabolic pathways, and therefore are a promising tool for understanding disease etiopathogenesis and the development of effective causal treatment. The aim of this systematic review was to analyze the metabolome of the respiratory epithelial lining fluid of patients with COPD, compared to healthy volunteers, refractory smokers, and subjects with other lung diseases. We included observational human studies. Sphingolipids, phosphatidylethanolamines, and sphingomyelins distinguished COPD from non-smokers; volatile organic compounds, lipids, and amino acids distinguished COPD from smokers without the disease. Five volatile organic compounds were correlated with eosinophilia and four were associated with a phenotype with frequent exacerbations. Fatty acids and ornithine metabolism were correlated with the severity of COPD. Metabolomics, by searching for biomarkers and distinguishing metabolic pathways, can allow us to understand the pathophysiology of COPD and the development of its phenotypes.

The Role of Chitinases in Chronic Airway Inflammation Associated with Tobacco Smoke Exposure.

Chitinases and chitinase-like proteins are thought to play a role in innate inflammatory responses. Our study aimed to assess whether chitinase concentration and activity in induced sputum (IS) of patients exposed to tobacco smoke are related to the level of airway inflammation including the level and activity of chitinases and chitinase-like proteins. The study included 22 patients with chronic obstructive pulmonary disease (COPD), 12 non-COPD smokers, and nine nonsmoking subjects. Sputum CHIT1 and YKL-40 levels and chitinolytic activity were compared with sputum IL-6, IL-8, IL-18, and MMP-9 levels. A hierarchical cluster analysis was also performed. Sputum YKL-40 was higher in COPD patients than in the control groups. Sputum CHIT1 and YKL-40 levels correlated with IS inflammatory cell count as well as with MMP-9 and IL-8 levels. Two main clusters were revealed: Cluster 1 had lower chitinase levels and activity, lower IS macrophage and neutrophil count, and lower IS IL-8, IL-18, and MMP-9 than Cluster 2. Comparison of COPD patients from both clusters revealed significant differences in the IS inflammatory profile despite comparable clinical and functional data. Our findings seem to confirm the involvement of chitinases in smoking-associated chronic airway inflammation and show that airway chitinases may be a potential novel marker in COPD phenotyping.

Pharmacological Inhibition of Chitotriosidase (CHIT1) as a Novel Therapeutic Approach for Sarcoidosis.

Introduction: Sarcoidosis is a systemic disease of unknown etiology characterized by granuloma formation in the affected tissues. The pathologically activated macrophages are causatively implicated in disease pathogenesis and play important role in granuloma formation. Chitotriosidase (CHIT1), macrophage-derived protein, is upregulated in sarcoidosis and its levels correlate with disease severity implicating CHIT1 in pathology. Methods: CHIT1 was evaluated in serum and bronchial mucosa and mediastinal lymph nodes specimens from sarcoidosis patients. The therapeutic efficacy of OATD-01 was assessed ex vivo on human bronchoalveolar lavage fluid (BALF) macrophages and in vivo in the murine models of granulomatous inflammation. Results: CHIT1 activity was significantly upregulated in serum from sarcoidosis patients. CHIT1 expression was restricted to granulomas and localized in macrophages. Ex vivo OATD-01 inhibited pro-inflammatory mediators' production (CCL4, IL-15) by lung macrophages. In the acute model of granulomatous inflammation in mice, OATD-01 showed anti-inflammatory effects reducing the percentage of neutrophils and CCL4 concentration in BALF. In the chronic model, inhibition of CHIT1 led to a decrease in the number of organized lung granulomas and the expression of sarcoidosis-associated genes. Conclusion: In summary, CHIT1 activity was increased in sarcoidosis patients and OATD-01, a first-in-class CHIT1 inhibitor, demonstrated efficacy in murine models of granulomatous inflammation providing a proof-of-concept for its clinical evaluation in sarcoidosis.

Evaluation of patients' satisfaction with bronchoscopy procedure.

BACKGROUND: The bronchoscopy (BS) experience provokes anxiety amongst some patients. It can have a negative impact on the course of the procedure and on the willingness of patients to undergo the next BS in the future. OBJECTIVE: We aimed to identify factors influencing patients' satisfaction with BS. METHODS: The prospective study had been conducted between January and June 2019. It included patients hospitalized in our Department, who underwent elective BS. Patients assessed their anxiety and satisfaction level before and after BS using the Visual Analogue Scale (VAS). Data concerning the course of the bronchoscopy was collected. RESULTS: The median level of anxiety prior to the procedure was moderate, higher in women (p<0.0001). The majority of patients (116/125, 93%) were satisfied with appropriate information before the procedure. Almost one-third of the interviewees (39/125, 31%) declared complete satisfaction (VAS = 0) with their procedure, 17 patients (14%) were dissatisfied (VAS >5/10). Overall 113 (90%) patients declared unconditional consent for future bronchoscopy. Multivariate linear regression analysis revealed two factors affecting patients' satisfaction with bronchoscopy: anxiety prior to BS (standardized regression coefficient ß = 0.264, p = 0.003) and discomfort (ß = 0.205, p = 0.018). Neither age, degree of amnesia, duration of the procedure nor its type added any significant value as factors affecting patient satisfaction. The most common factors inducing patients' discomfort during BS were local anesthesia of the throat (56/125, 45%) and cough (47/125, 38%). CONCLUSIONS: Low anxiety level before bronchoscopy and reduced discomfort during the procedure are associated with better patient satisfaction. Thus, it is important to reduce patient anxiety and discomfort during the procedure.

Guidelines of the Polish Respiratory Society on the Diagnosis and Treatment of Progressive Fibrosing Interstitial Lung Diseases Other than Idiopathic Pulmonary Fibrosis.

The recommendations were developed as answers to previously formulated questions concerning everyday diagnostic and therapeutic challenges. They were developed based on a review of the current literature using the GRADE methodology. The experts suggest that PF-ILD be diagnosed based on a combination of different criteria, such as the aggravation of symptoms, progression of radiological lesions, and worsening of lung function test parameters. The experts recommend a precise diagnosis of an underlying disease, with serological testing for an autoimmune disease always being included. The final diagnosis should be worked out by a multidisciplinary team (MDT). Patients with an interstitial lung disease other than IPF who do not meet the criteria for the progressive fibrosis phenotype should be monitored for progression, and those with systemic autoimmune diseases should be regularly monitored for signs of interstitial lung disease. In managing patients with interstitial lung disease associated with autoimmune diseases, an opinion of an MDT should be considered. Nintedanib rather than pirfenidon should be introduced in the event of the ineffectiveness of the therapy recommended for the treatment of the underlying disease, but in some instances, it is possible to start antifibrotic treatment without earlier immunomodulatory therapy. It is also admissible to use immunomodulatory and antifibrotic drugs simultaneously. No recommendations were made for or against termination of anti-fibrotic therapy in the case of noted progression during treatment of a PF-ILD other than IPF. The experts recommend that the same principles of non-pharmacological and palliative treatment and eligibility for lung transplantation should be applied to patients with an interstitial lung disease other than IPF with progressive fibrosis as in patients with IPF.

Guidelines of the Polish Respiratory Society on the Diagnosis and Treatment of Progressive Fibrosing Interstitial Lung Diseases Other than Idiopathic Pulmonary Fibrosis

The recommendations were developed as answers to previously formulated questions concerning everyday diagnostic and therapeutic challenges. They were developed based on a review of the current literature using the GRADE methodology. The experts suggest that PF-ILD be diagnosed based on a combination of different criteria, such as the aggravation of symptoms, progression of radiological lesions, and worsening of lung function test parameters. The experts recommend a precise diagnosis of an underlying disease, with serological testing for an autoimmune disease always being included. The final diagnosis should be worked out by a multidisciplinary team (MDT). Patients with an interstitial lung disease other than IPF who do not meet the criteria for the progressive fibrosis phenotype should be monitored for progression, and those with systemic autoimmune diseases should be regularly monitored for signs of interstitial lung disease. In managing patients with interstitial lung disease associated with autoimmune diseases, an opinion of an MDT should be considered. Nintedanib rather than pirfenidon should be introduced in the event of the ineffectiveness of the therapy recommended for the treatment of the underlying disease, but in some instances, it is possible to start antifibrotic treatment without earlier immunomodulatory therapy. It is also admissible to use immunomodulatory and antifibrotic drugs simultaneously. No recommendations were made for or against termination of anti-fibrotic therapy in the case of noted progression during treatment of a PF-ILD other than IPF. The experts recommend that the same principles of non-pharmacological and palliative treatment and eligibility for lung transplantation should be applied to patients with an interstitial lung disease other than IPF with progressive fibrosis as in patients with IPF.

Therapeutic decisions in a cohort of patients with idiopathic pulmonary fibrosis: a multicenter, prospective survey from Poland.

Background: Pirfenidone and nintedanib are considered as the standard of care in idiopathic pulmonary fibrosis (IPF), but there is no consensus as to which of these two agents should be regarded as first-line treatment. Objective: To provide real-world data on therapeutic decisions of pulmonary specialists, particularly the choice of the antifibrotic drug in patients with IPF. Methods: This was a multicenter, prospective survey collecting clinical data of patients with IPF considered as candidates for antifibrotic treatment between September 2019 and December 2020. Clinical characteristics and information on the therapeutic approach were retrieved. Statistical evaluation included multiple logistic regression analysis with stepwise model selection. Results: Data on 188 patients [74.5% male, median age 73 (interquartile range, 68-78) years] considered for antifibrotic therapy were collected. Treatment was initiated in 138 patients, while 50 patients did not receive an antifibrotic, mainly due to the lack of consent for treatment and IPF severity. Seventy-two patients received pirfenidone and 66 received nintedanib. Dosing protocol (p < 0.01) and patient preference (p = 0.049) were more frequently associated with the choice of nintedanib, while comorbidity profile (p = 0.0003) and concomitant medication use (p = 0.03) were more frequently associated with the choice of pirfenidone. Age (p = 0.002), lung transfer factor for carbon monoxide (TLCO) (p = 0.001), and gastrointestinal bleeding (p = 0.03) were significantly associated with the qualification for the antifibrotic treatment. Conclusion: This real-world prospective study showed that dose protocol and patient preference were more frequently associated with the choice of nintedanib, while the comorbidity profile and concomitant medication use were more frequently associated with the choice of pirfenidone. Age, TLCO, and history of gastrointestinal bleeding were significant factors influencing the decision to initiate antifibrotic therapy.

Inhibition of CHIT1 as a novel therapeutic approach in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a progressive and eventually fatal lung disease with a complex etiology. Approved drugs, nintedanib and pirfenidone, modify disease progression, but IPF remains incurable and there is an urgent need for new therapies. We identified chitotriosidase (CHIT1) as new driver of fibrosis in IPF and a novel therapeutic target. We demonstrate that CHIT1 activity and expression are significantly increased in serum (3-fold) and induced sputum (4-fold) from IPF patients. In the lungs CHIT1 is expressed in a distinct subpopulation of profibrotic, disease-specific macrophages, which are only present in patients with ILDs and CHIT1 is one of the defining markers of this fibrosis-associated gene cluster. To define CHIT1 role in fibrosis, we used the therapeutic protocol of the bleomycin-induced pulmonary fibrosis mouse model. We demonstrate that in the context of chitinase induction and the macrophage-specific expression of CHIT1, this model recapitulates lung fibrosis in ILDs. Genetic inactivation of Chit1 attenuated bleomycin-induced fibrosis (decreasing the Ashcroft scoring by 28%) and decreased expression of profibrotic factors in lung tissues. Pharmacological inhibition of chitinases by OATD-01 reduced fibrosis and soluble collagen concentration. OATD-01 exhibited anti-fibrotic activity comparable to pirfenidone resulting in the reduction of the Ashcroft score by 32% and 31%, respectively. These studies provide a preclinical proof-of-concept for the antifibrotic effects of OATD-01 and establish CHIT1 as a potential new therapeutic target for IPF.

Phenotypic Variations of Mild-to-Moderate Obstructive Pulmonary Diseases According to Airway Inflammation and Clinical Features.

PURPOSE: Asthma and chronic obstructive pulmonary disease (COPD) are complex and heterogeneous inflammatory diseases. We sought to investigate distinct disease profiles based on clinical, cellular and molecular data from patients with mild-to-moderate obstructive pulmonary diseases. PATIENTS AND METHODS: Patients with mild-to-moderate allergic asthma (n=30) and COPD (n=30) were prospectively recruited. Clinical characteristics and induced sputum were collected. In total, 35 mediators were assessed in induced sputum. Logistic regression analysis was conducted to identify the optimal factors that were able to discriminate between asthma and COPD. Further, the data were explored using hierarchical clustering in order to discover and compare clusters of combined samples of asthma and COPD patients. Clinical parameters, cellular composition, and sputum mediators of asthma and COPD were assessed between and within obtained clusters. RESULTS: We found five clinical and biochemical variables, namely IL-6, IL-8, CCL4, FEV1/VC ratio pre-bronchodilator (%), and sputum neutrophils (%) that differentiated asthma and COPD and were suitable for discrimination purposes. A combination of those variables yielded high sensitivity and specificity in the differentiation between asthma and COPD, although only FEV1/VC ratio pre-bronchodilator (%) proven significant in the combined model. In cluster analysis, two main clusters were identified: cluster 1, asthma predominant with evidence of eosinophilic airway inflammation and low level of Th1 and Th2 cytokines; and cluster 2, COPD predominant with elevated levels of Th1 and Th2 mediators. CONCLUSION: The inflammatory profile of sputum samples from patients with stable mild-to-moderate asthma and COPD is not disease specific, varies within the disease and might be similar between these diseases. This study highlights the need for phenotyping the mild-to-moderate stages according to their clinical and molecular features.

Interactions of nasal epithelium with macrophages and dendritic cells variously alter urban PM-induced inflammation in healthy, asthma and COPD.

Urban particulate matter (UPM) is an important trigger of airway inflammation. The cross-talk between the external and internal matrix in the respiratory tract occurs due to the transepithelial network of macrophages/dendritic cells. This study characterized the immune processes induced by the epithelium after UPM exposure in special regard to interactions with monocyte-derived dendritic cells (moDCs) and monocyte-derived macrophages (moMφs) in obstructive lung diseases. A triple-cell co-culture model (8 controls, 10 asthma, and 8 patients with COPD) utilized nasal epithelial cells, along with moMφs, and moDCs was exposed to UPM for 24 h. The inflammatory response of nasal epithelial cells to UPM stimulation is affected differently by cell-cell interactions in healthy people, asthma or COPD patients of which the interactions with DCs had the strongest impact on the inflammatory reaction of epithelial cells after UPM exposure. The epithelial remodeling and DCs dysfunction might accelerate the inflammation after air pollution exposure in asthma and COPD.

The use of a mobile spirometry with a feedback quality assessment in primary care setting - A nationwide cross-sectional feasibility study.

OBJECTIVES: Mobile phone-linked portable spirometers are light-weight, easy to use and low cost, with new software to facilitate data collection. In this study we investigated the feasibility of the AioCare® mobile spirometry in primary care. METHODS: In this nationwide, cross-sectional study, AioCare® spirometers (HealthUp, Poland) were distributed among primary healthcare centres across Poland. Operators (primary care professionals) received a 2-h training session, after which spirometry was performed in patients attending routine visits with respiratory symptoms or risk factors for obstructive airway diseases. Spirometry was considered technically correct when at least three manoeuvres met ERS/ATS acceptability and repeatability criteria. The most common spirometry errors were assessed and stepwise logistic regression was applied to identify factors associated with technically correct spirometry. Airway obstruction was defined as FEV1/FVC below the lower limit of normal. A restrictive pattern was defined as FVC below the lower limit of normal. RESULTS: Between 1 September 2018 and 1 September 2019, 10,936 spirometry examinations were performed in 9855 patients by 673 operators. 5347 (49%) spirometry examinations met both acceptability and repeatability criteria. The most common error was plateau error (17.7%). Operator age >40 years (OR 1.49, 95% CI 1.35-1.64) and repetition of the examination at the same visit (OR 1.90, 95% CI 1.66-2.16) increased the likelihood of a technically correct examination. Airway obstruction was found in 17% of correctly performed spirometry examinations. CONCLUSIONS: Our nationwide study suggests that use of the AioCare® mobile spirometer in primary care could be feasible. More intensive and continual training should be implemented to improve the quality of spirometry examinations.

Periostin concentration in exhaled breath condensate in children with mild asthma.

OBJECTIVE: Periostin is considered to be a marker of eosinophilic inflammation in patients with asthma. However, there are no literature data on exhaled breath condensate (EBC) periostin level in pediatric patients with asthma. The aim of this study was to analyze EBC periostin concentration in children with mild asthma and to evaluate the potential usefulness of EBC periostin level as a biomarker for the disease. METHODS: EBC and serum periostin concentrations were measured by enzyme-linked immunosorbent assay in 23 children with asthma and 23 healthy controls. RESULTS: EBC periostin concentration was 250- to 780-fold lower than that found in serum. No significant differences between serum nor EBC periostin concentration in asthmatics and the control group were showed. The comparison between children with Th2 and non-Th2 type of asthma did not show significant differences in periostin concentration, both in serum and EBC. Serum periostin concentration inversely correlated with BMI and age not only in asthma patients but also in controls. CONCLUSIONS: In children with mild asthma, periostin may be measured not only in serum but also in EBC. The low periostin level in patients with mild asthma and lack of difference between asthmatic subjects and controls indicate that EBC periostin may not be useful as an asthma biomarker in this group.

Is the composition of exhaled breath condensate a key to explain the course of COVID-19 in children?

INTRODUCTION: The relative resistance of children to severe course of the novel coronavirus infection remains unclear. We hypothesized that there might be a link between this phenomenon and observation from our previous studies concerning an inhibitory or cytotoxic effect of exhaled breath condensate (EBC) on endothelial cell cultures in children. AIM: Since we could not find any data on the similar effect caused by EBC in adults, the aim of our study was to evaluate and compare the biological activity of EBC in adults and children in an experimental in vitro model. Furthermore, in order to identify a putative agent responsible for these properties of EBC in children, we attempted to analyse the composition of selected EBC samples. MATERIAL AND METHODS: The influence of EBC samples on metabolic activity of endothelial cell line C-166 was assessed using colorimetric tetrazolium salt reduction assay (MTT assay). Selected EBC samples were fractionated using size exclusion chromatography and subjected to mass spectrometry analysis. RESULTS: Exhaled breath condensates in healthy children, but not in adults, revealed a cytotoxic effect on in vitro cell cultures. This effect was most significant in condensate fraction, which contained a prominent 4.8 kDa peak in the mass spectra. CONCLUSIONS: Breath condensates of healthy children contain the factor which reveals the inhibitory/cytotoxic effect on endothelial cell cultures. Although the physiological role of this agent remains unclear, its identification may potentially be useful in ongoing research on SARS-CoV-2/COVID-19.