OBJECTIVES: The diaphragm changes position and respiratory excursions during postural loading. However, it is unclear how it reacts to lifting a load while breath-holding or breathing with simultaneous voluntary contraction of the abdominal muscles (VCAM). This study analyzed diaphragm motion in healthy individuals during various postural-respiratory situations. METHODS: 31 healthy participants underwent examination of the diaphragm using M-mode ultrasonography, spirometry, and abdominal wall tension (AWT) measurements. All recordings were performed simultaneously during three consecutive scenarios, i.e., 1. Lifting a load without breathing; 2. Lifting a load and breathing naturally; 3. Lifting a load and breathing with simultaneous VCAM. RESULTS: Using paired-samples t-tests, lifting a load without breathing displaced the diaphragm's expiratory position more caudally (P < .001), with no change noted in the inspiratory position (P = .373). During lifting a load breathing naturally, caudal displacement of the diaphragm's inspiratory position was presented (P < .001), with no change noted in the expiratory position (P = 0.20) compared to tidal breathing. Total diaphragm excursion was greater when loaded (P = .002). Lifting a load and breathing with VCAM demonstrated no significant changes in diaphragm position for inspiration, expiration, or total excursion compared to natural loaded breathing. For all scenarios, AWT measures were greater when lifting a load (P < .001). CONCLUSION: In healthy individuals, caudal displacement and greater excursions of the diaphragm occurred when lifting a load. The postural function of the diaphragm is independent of its respiratory activity and is not reduced by the increase in AWT.
- MeSH
- bránice * diagnostické zobrazování fyziologie MeSH
- dýchání * MeSH
- lidé MeSH
- svalová kontrakce MeSH
- ultrasonografie MeSH
- vydechnutí MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Exhaled breath condensate (EBC) is an attractive, non-invasive sample for clinical diagnostics. During EBC collection, its composition is influenced by the collection temperature, a factor that is often not thoroughly monitored and controlled. In this study, we assembled a novel, simple, portable, and inexpensive device for EBC collection, able to maintain a stable temperature at any value between -7 °C and +12 °C. The temperature was controlled using a microcontroller and a thermoelectric cooler that was employed to cool the aluminum block holding the glass tube or the polypropylene syringe. The performance of the novel sampler was compared with the passively cooled RTube™ and a simple EBC sampler, in which the temperature was steadily increasing during sampling. The developed sampler was able to maintain a stable temperature within ±1 °C. To investigate the influence of different sampling temperatures (i.e., +12, -7, -80 °C) on the analyte content in EBC, inorganic ions and organic acids were analyzed by capillary electrophoresis with a capacitively coupled contactless conductivity detector. It was shown that the concentration of metabolites decreased significantly with decreasing temperature. The portability and the ability to keep a stable temperature during EBC sampling makes the developed sampler suitable for point-of-care diagnostics.
- Klíčová slova
- Arduino, Capillary electrophoresis, Collection device, Exhaled breath condensate, Ion analysis, Temperature control,
- MeSH
- biologické markery MeSH
- dechové testy * MeSH
- elektroforéza kapilární MeSH
- point of care testing MeSH
- teplota MeSH
- vydechnutí * MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- biologické markery MeSH
Individual studies have suggested the utility of fractional exhaled nitric oxide (FeNO) measurement in detecting cough-variant asthma and eosinophilic bronchitis in patients with chronic cough. The aim of this study was to clarify a correlation of cough reflex sensitivity and fractional exhaled nitric oxide in asthmatic children. 25 children with asthma and 15 controls were submitted to cough reflex sensitivity measurement - capsaicin aerosol in doubling concentrations (from 0.61 to 1250 micromol/l) was inhaled by a single breath method. Concentrations of capsaicin causing two (C2) and five coughs (C5) were reported. Fractional exhaled nitric oxide (FeNO) measurement was included. Asthmatic children' (11 boys and 14 girls, mean age 9+/-1 years) and control group (unconfirmed diagnosis of asthma) (6 boys and 9 girls, mean age 8+/-1 years) were included into the study. FeNO vs. C2 in asthma (Spearman´s rank correlation: -0.146, p=0.49); FENO vs. C5 in asthma (Spearman´s rank correlation: -0.777, p=0.71). We found that there is no correlation between cough reflex sensitivity and fractional exhaled nitric oxide either in children with asthma or in the control group.
- MeSH
- alergie diagnóza etiologie metabolismus MeSH
- bronchiální astma komplikace metabolismus MeSH
- dítě MeSH
- kašel diagnóza etiologie metabolismus MeSH
- lidé MeSH
- oxid dusnatý metabolismus MeSH
- reflex fyziologie MeSH
- respirační funkční testy MeSH
- ROC křivka MeSH
- vydechnutí MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- oxid dusnatý MeSH
Three experiments were conducted with a volunteer to test the kinetics of the 222Rn exhalation after a short-time exposure to an elevated 222Rn air concentration. Radon concentration in an exhaled air was measured, complemented by whole body counting of 222Rn decay products in a body. Exhaled activities are compared with the prediction of the recent ICRP biokinetic model for radon. While a rapid equilibration of the exhaled radon activity concentration with that in the air inhaled corresponded with the model, the measured 222Rn exhalation rate was significantly less than modelled. Five hours after termination of the inhalation phase, the radon concentration in the exhaled air decreased to levels expected for non-elevated indoor radon activity concentration. Whole body activities of the 222Rn decay products were found higher than expected. Inhalation of the unattached fraction or residual activity of decay products in the air inhaled may be the explanation.
- MeSH
- kinetika MeSH
- lidé MeSH
- radioaktivní látky znečišťující vzduch * analýza MeSH
- radon * analýza MeSH
- vydechnutí MeSH
- znečištění vzduchu ve vnitřním prostředí * analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- radioaktivní látky znečišťující vzduch * MeSH
- Radon-222 MeSH Prohlížeč
- radon * MeSH
BACKGROUND: The widespread application of engineered nanomaterials (ENMs) and the increasing likelihood of general and occupational exposure raised concerns on their possible human health impact. ENMs, in fact, may induce alterations in different organ systems, and particularly in the respiratory tract. This makes it important to identify possible biomarkers of early lung effect in exposed workers. In this regard, the possibility to use the fractional exhaled levels of nitric oxide (FENO) in biological monitoring has attracted considerable interest. OBJECTIVE: To comprehensively assess the role of FENO as a possible biomarker of lung effect in ENM exposed workers. METHODS: A systematic search was performed on Pubmed, Scopus, and ISI Web of Knowledge databases according to the PRISMA guidelines. RESULTS: Seven studies investigated FENO in workers exposed to different kinds of metal- (i.e. silver and gold), metal oxide- (titanium and silica dioxide), and carbon-based ENMs (carbon nanotubes). In general, no significant alterations were detected between exposed workers and controls. CONCLUSION: Definite conclusion on the function of FENO in occupational biological monitoring cannot be extrapolated due to the limited number of available studies and the small size of investigated populations. Additionally, the lack of environmental monitoring data and the fragmented knowledge on ENM modes of action prevent to establish dose-response relationships. Future research appears necessary to deeply define the possibility to employ FENO as an early biomarker of lung effects taking in consideration possible occupational exposure issues, i.e. differently characterized ENMs and work tasks, as well as individual influencing factors, i.e. smoking and atopy.
- Klíčová slova
- Fractional exhaled nitric oxide, biomarkers, exhaled breath condensate, nanomaterials, nanoparticles, occupational exposure,
- MeSH
- biologické markery MeSH
- dechové testy MeSH
- lidé MeSH
- nanostruktury * toxicita MeSH
- nanotrubičky uhlíkové MeSH
- oxid dusnatý MeSH
- pracoviště MeSH
- vydechnutí MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- biologické markery MeSH
- nanotrubičky uhlíkové MeSH
- oxid dusnatý MeSH
RATIONALE: The analysis of volatile organic compounds (VOCs) within exhaled breath potentially offers a non-invasive method for the detection and surveillance of human disease. Oral contamination of exhaled breath may influence the detection of systemic VOCs relevant to human disease. This study aims to assess the impact of oral cleansing strategies on exhaled VOC levels in order to standardise practice for breath sampling. METHODS: Ten healthy volunteers consumed a nutrient challenge followed by four oral cleansing methods: (a) water, (b) saltwater, (c) toothbrushing, and (d) alcohol-free mouthwash. Direct breath sampling was performed using selected ion flow tube mass spectrometry after each intervention. RESULTS: Proposed reactions suggest that volatile fatty acid and alcohol levels (butanoic, pentanoic acid, ethanol) declined with oral cleansing interventions, predominantly after an initial oral rinse with water. Concentrations of aldehydes and phenols (acetaldehyde, menthone, p-cresol) declined with oral water rinse; however, they increased after toothbrushing and mouthwash use, secondary to flavoured ingredients within these products. No significant reductions were observed with sulphur compounds. CONCLUSIONS: Findings suggest that oral rinsing with water prior to breath sampling may reduce oral contamination of VOC levels, and further interventions for oral decontamination with flavoured products may compromise results. This intervention may serve as a simple and inexpensive method of standardisation within breath research.
- MeSH
- čištění zubů MeSH
- dechové testy metody MeSH
- hmotnostní spektrometrie metody MeSH
- lidé MeSH
- odběr biologického vzorku metody MeSH
- orální hygiena MeSH
- těkavé organické sloučeniny analýza MeSH
- vydechnutí MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- těkavé organické sloučeniny MeSH
As stated by Korpáš and Tomori (1979), cough is the most important airway protective reflex which provides airway defensive responses to nociceptive stimuli. They recognized that active expiratory efforts, due to the activation of caudal ventral respiratory group (cVRG) expiratory premotoneurons, are the prominent component of coughs. Here, we discuss data suggesting that neurons located in the cVRG have an essential role in the generation of both the inspiratory and expiratory components of the cough reflex. Some lines of evidence indicate that cVRG expiratory neurons, when strongly activated, may subserve the alternation of inspiratory and expiratory cough bursts, possibly owing to the presence of axon collaterals. Of note, experimental findings such as blockade or impairment of glutamatergic transmission to the cVRG neurons lead to the view that neurons located in the cVRG are crucial for the production of the complete cough motor pattern. The involvement of bulbospinal expiratory neurons seems unlikely since their activation affects differentially expiratory and inspiratory muscles, while their blockade does not affect baseline inspiratory activity. Thus, other types of cVRG neurons with their medullary projections should have a role and possibly contribute to the fine tuning of the intensity of inspiratory and expiratory efforts.
- MeSH
- 6-kyano-7-nitrochinoxalin-2,3-dion aplikace a dávkování MeSH
- antagonisté excitačních aminokyselin aplikace a dávkování MeSH
- kašel patofyziologie prevence a kontrola MeSH
- lidé MeSH
- mechanika dýchání účinky léků fyziologie MeSH
- medulla oblongata účinky léků fyziologie MeSH
- mikroinjekce metody MeSH
- nadechnutí účinky léků fyziologie MeSH
- nervus phrenicus účinky léků fyziologie MeSH
- neurony účinky léků fyziologie MeSH
- reflex účinky léků fyziologie MeSH
- vydechnutí účinky léků fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- 6-kyano-7-nitrochinoxalin-2,3-dion MeSH
- antagonisté excitačních aminokyselin MeSH
FeNO measurement is a validated non-invasive technique, which is used for diagnosis and monitoring of asthma. It would be desirable to find a reliable method to monitor allergic rhinitis (AR) via measurement of FeNO, and/or nasal nitric oxide (nNO). The aim of our study was the assessment of the efficacy of FeNO and nNO as markers in AR treatment. FeNO and nNO were measured with the portable NO analyser (NIOX MINO®) in healthy participants and in patients with AR. The patients were examined during the pollen season and out of it. The effect of local corticosteroids and antihistamine therapy was observed in patients with AR during pollen season after three weeks of therapy. There are significant differences between FeNO and nNO in patients with AR compared to healthy controls at all set points of measurements. While FeNO responded well to the treatment with both antihistamines and combined therapy, nNO decreased only after combined therapy with antihistamines and nasal corticosteroids. nNO monitoring alone is not a suitable method to monitor inflammation of the upper airways in AR and its suppression by anti-allergic treatment and should be correlated with other markers as FeNO or symptom scores.
- MeSH
- alergická rýma diagnóza farmakoterapie metabolismus MeSH
- antihistaminika aplikace a dávkování MeSH
- aplikace intranazální MeSH
- biologické markery analýza metabolismus MeSH
- dospělí MeSH
- hormony kůry nadledvin aplikace a dávkování MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- nosní sliznice účinky léků metabolismus MeSH
- oxid dusnatý analýza metabolismus MeSH
- vydechnutí účinky léků fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antihistaminika MeSH
- biologické markery MeSH
- hormony kůry nadledvin MeSH
- oxid dusnatý MeSH
Cough is an important mechanism of airway clearance. In patients who present weak and ineffective cough, augmentation techniques aim to assist or simulate the maneuver. These techniques target different phases of the cough cycle, mainly the inspiratory and expiratory phases, through assisted inspiration, assisted expiration and their combination. They include the manual hyperinflation, ventilator hyperinflation, glossopharyngeal breathing, manually assisted cough and mechanical insufflator-exsufflator, each applied individually or in different combinations. The aim of this review is to investigate the effectiveness and safety of cough augmentation techniques. Findings support that all commonly used techniques can theoretically improve airway clearance, as they generate higher cough peak flows compared to unassisted cough. Still, the studies assessing cough augmentation present considerable limitations and the direct comparison of different techniques is challenging. Current evidence indicate that cough peak flow shows higher increase with the combination of assisted inspiration and expiration, and improvement is greater in patients with lower unassisted values. Associated adverse events are infrequent.
- MeSH
- chronická obstrukční plicní nemoc patofyziologie terapie MeSH
- insuflace metody MeSH
- kašel etiologie patofyziologie MeSH
- lidé MeSH
- nadechnutí fyziologie MeSH
- skolióza patofyziologie terapie MeSH
- umělé dýchání metody MeSH
- vrcholová exspirační průtoková rychlost fyziologie MeSH
- vydechnutí fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
BACKGROUND: While acrylates are well-known skin sensitizers, they are not classified as respiratory sensitizers although several cases of acrylate-induced occupational asthma (OA) have been reported. OBJECTIVE: To evaluate the characteristics of acrylate-induced OA in a large series of cases and compare those with OA induced by other low-molecular-weight (LMW) agents. METHODS: Jobs and exposures, clinical and functional characteristics, and markers of airway inflammation were analyzed in an international, multicenter, retrospective cohort of subjects with OA ascertained by a positive inhalation challenge to acrylates (n = 55) or other LMW agents (n = 418) including isocyanates (n = 125). RESULTS: Acrylate-containing glues were the most prevalent products, and industrial manufacturing, dental work, and beauty care were typical occupations causing OA. Work-related rhinitis was more common in acrylate-than in isocyanate-induced asthma (P < .001). The increase in postchallenge fractional exhaled nitric oxide was significantly greater in acrylate-induced OA (26.0; 8.2 to 38.0 parts per billion [ppb]) than in OA induced by other LMW agents (3.0; -1.0 to 10.0 ppb; P < .001) or isocyanates (5.0; 2.0 to 16.0 ppb; P = .010). Multivariable models confirmed that OA induced by acrylates was significantly and independently associated with a postchallenge increase in fractional exhaled nitric oxide (≥17.5 ppb). CONCLUSIONS: Acrylate-induced OA shows specific characteristics, concomitant work-related rhinitis, and exposure-related increases in fractional exhaled nitric oxide, suggesting that acrylates may induce asthma through different immunologic mechanisms compared with mechanisms through which other LMW agents may induce asthma. Our findings reinforce the need for a reevaluation of the hazard classification of acrylates, and further investigation of the pathophysiological mechanisms underlying their respiratory sensitizing potential.
- Klíčová slova
- Acrylate, Cyanoacrylate, Fractional exhaled nitric oxide, Low-molecular-weight agent, Methacrylate, Occupational asthma,
- MeSH
- akryláty škodlivé účinky MeSH
- kohortové studie MeSH
- lidé MeSH
- oxid dusnatý MeSH
- profesionální astma * epidemiologie MeSH
- retrospektivní studie MeSH
- vydechnutí MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- Názvy látek
- akryláty MeSH
- oxid dusnatý MeSH