Exhaled breath condensate (EBC) pH is considered to reflect the acid-base balance of the airways. Current pH measurements do not take into account the effect of CO₂. The aim of the present study was to determine the effect of condensate CO₂partial pressure on pH and to provide a more precise mode of EBC pH determination.Condensate pH and CO₂partial pressure were measured in parallel from 12 healthy volunteers and 12 asthmatics using a blood gas analyser in neat, argon de-aerated and CO₂-loaded samples. The regression analysis was used to test the relationship between pH and CO₂, and to calculate the pH at a CO₂level of 5.33 kPa (physiological alveolar CO₂partial pressure). Reproducibility of different pH readings was compared using the Bland–Altman test.Condensate CO₂concentration was variable both in neat and argon de-aerated samples. There was a close negative logarithmic relationship between CO₂and pH. Calculation of pH at a CO₂level of 5.33 kPa provided reproducibility approximately six times as good as that of the currently used measurements.Condensate CO₂partial pressure influences pH measurements. Determination of pH at a standard CO₂level provides the most reproducible condensate pH values to date.

Although the importance of cysteinyl leukotrienes (Cys-LTs) in exercise-induced bronchoconstriction (EIB) is supported by various sources of evidence, how the concentration of these mediators change during the development of EIB has not been investigated. Our goal was to determine the effect of exercise on the concentration of airway Cys-LT in asthmatic patients by measuring Cys-LT in exhaled breath condensate (EBC). Seventeen atopic asthmatic patients with a previous history of EIB and six healthy volunteers were studied. Before and two times within 10 minutes after exercise challenge, FEV₁ was measured and EBC was collected for Cys-LT measurement. Exhaled nitric oxide level, a marker of airway inflammation, was also determined at baseline. Baseline Cys-LT level was higher in the asthmatic group versus healthy subjects (168 pg/mL /112-223/ vs. 77 pg/mL /36-119/, p = .03). EBC Cys-LT concentration increased in all asthmatic patients post-exercise (n = 17, p = .03), with the increase significantly greater in patients developing exercise-induced bronchospasm (n = 7, p = .03), whereas no change was observed in healthy controls (p = .59). The exercise-induced fall in FEV(1) in asthmatics was related to the increase in EBC Cys-LT concentration (r = -0.40, p = .03). Our study shows that Cys-LT concentration of EBC is elevated minutes after physical exercise in asthmatic patients and strongly supports the concept that the release of this mediator is involved in the development of EIB.

Genetic alterations are well known to be related to the pathogenesis and prognosis of papillary thyroid carcinoma (PTC). Some miRNA expression dysregulations have previously been described in the context of cancer development including thyroid carcinoma. In our study, we performed original molecular diagnostics on tissue samples related to our own patients. We aimed to identify all dysregulated miRNAs in potential association with PTC development via sequencing much higher numbers of control-matched PTC tissue samples and analyzing a wider variety of miRNA types than previous studies. We analyzed the expression levels of 2656 different human miRNAs in the context of 236 thyroid tissue samples (118 tumor and control pairs) related to anonymized PTC cases. Also, KEGG pathway enrichment analysis and GO framework analysis were used to establish the links between miRNA dysregulation and certain biological processes, pathways of signaling, molecular functions, and cellular components. A total of 30 significant differential miRNA expressions with at least ±1 log₂ fold change were found related to PTC including, e.g., miR-551b, miR-146b, miR-221, miR-222, and miR-375, among others, being highly upregulated, as well as miR-873 and miR-204 being downregulated. In addition, we identified miRNA patterns in vast databases (KEGG and GO) closely similar to that of PTC including, e.g., miRNA patterns of prostate cancer, HTLV infection, HIF-1 signaling, cellular responses to growth factor stimulus and organic substance, and negative regulation of gene expression. We also found 352 potential associations between certain miRNA expressions and states of clinicopathological variables. Our findings—supported by the largest case number of original matched-control PTC–miRNA relation research—suggest a distinct miRNA expression profile in PTC that could contribute to a deeper understanding of the underlying molecular mechanisms promoting the pathogenesis of the disease. Moreover, significant miRNA expression deviations and their signaling pathways in PTC presented in our study may serve as potential biomarkers for PTC diagnosis and prognosis or even therapeutic targets in the future.

Background: Despite a large number of published studies, the effect of vitamin D3 supplementation on mortality in hospitalized patients, as well as the recommended dose and duration of therapy, is unclear. In our retrospective study, we aimed to investigate the impact of vitamin D deficiency and moderately high-dose vitamin D3 supplementation on mortality and disease outcomes in patients with COVID-19 infection. Methods: We analyzed data from 148 COVID-19-infected hospitalized patients in two different departments, Internal Medicine and Oncology, at Semmelweis University. The severity of COVID-19 and the treatment used were the same except at one of the departments, where patients received circa 90,000 IU of vitamin D3. We compared in-hospital mortality rates between the groups. In a subgroup analysis, we evaluated the efficacy and safety of vitamin D3 supplementation by assessing 25(OH)D and 1,25(OH)₂D concentrations on days 0, 4, and 8. Results: As a result of the supplementation, the deficiency was resolved in 4 days in deficient patients, and none of the 25(OH)D or 1,25(OH)₂D concentrations exceeded the normal range. Mortality was significantly lower and decreased 67% in the group receiving vitamin D3 supplementation, regardless of baseline 25(OH)D concentrations. Conclusions: The supplemental dosage, 3 × 30,000 IU of vitamin D3, is effective and safe and may reduce mortality in COVID-19 infection.