Search results for "Exhalation"
showing 10 items of 35 documents
Recycling of 3He from lung magnetic resonance imaging
2011
We have developed the means to recycle 3He exhaled by patients after imaging the lungs using magnetic resonance of hyperpolarized 3He. The exhaled gas is collected in a helium leak proof bag and further compressed into a steel bottle. The collected gas contains about 1–2% of 3He, depending on the amount administered and the number of breaths collected to wash out the 3He gas from the lungs. 3He is separated from the exhaled air using zeolite molecular sieve adsorbent at 77 K followed by a cold head at 8 K. Residual gaseous impurities are finally absorbed by a commercial nonevaporative getter. The recycled 3He gas features high purity, which is required for repolarization by metastability ex…
Noninvasive methods for the detection of upper and lower airway inflammation in atopic children
2006
Background Exhaled nitric oxide (FE NO ) and exhaled breath condensate (EBC) are noninvasive methods to assess inflammation. Objective To investigate the role of the FE NO and of the EBC pH and IL-5 levels in atopic children. Methods We evaluated oral and nasal FE NO and the pH and IL-5 of oral and nasal EBC in children with atopic dermatitis (AD; n=18), allergic rhinitis (AR; n=18), intermittent asthma (n = 21), moderate persistent asthma (n = 18), and healthy controls (HCs; n=16). Results Oral FE NO was significantly increased in asthma, whereas the nasal values were increased in AR and asthma in comparison with HCs. The pH of oral EBC was lower in AD and asthma than in AR and HCs, wherea…
Long-term effects of commercial and congeneric polychlorinated biphenyls on ethane production and malondialdehyde levels, indicators of in vivo lipid…
1988
Ethane exhalation was increased in male Sprague-Dawley rats following a single intraperitoneal (IP) injection of Aroclor 1254 (500 mg/kg). In the first 2 weeks following Aroclor 1254 treatment, the increase in ethane exhalation was due to an inhibition of metabolism of endogenous ethane rather than to an increase in ethane production. In weeks 3 and 4 following Aroclor 1254 administration, metabolic clearance of ethane returned to and exceeded control levels, while ethane production increased to approximately twice the control rates (day 30). The HPLC determination of in situ hepatic malondialdehyde levels revealed a 2-fold increase in malondialdehyde content on day 30 following the Aroclor…
The influence of smoking status on exhaled breath profiles in asthma and COPD patients
2021
Breath analysis using eNose technology can be used to discriminate between asthma and COPD patients, but it remains unclear whether results are influenced by smoking status. We aim to study whether eNose can discriminate between ever- vs. never-smokers and smoking <
Quantitative evaluation of ethane and n-pentane as indicators of lipid peroxidation in vivo.
1983
The use of exhalation of ethane and n-pentane in experimental animals as parameters of lipid peroxidation led to an examination of pharmacokinetics of both compounds in rats. When rats were exposed, in a closed desiccator jar chamber, to a wide range of ethane concentrations, linear elimination pharmacokinetics were observed. n-Pentane, when concentrations higher than 100 ppm were applied, displayed saturation kinetics. These were formally explained by action of two competing metabolizing pathways or enzymes. Application of preexisting models could describe exhalation of both ethane and n-pentane by untreated control rats. Stimulation of lipid peroxidation by ferrous ions or by carbon tetra…
Noninvasive assessment of respiratory muscle strength and activity in Myotonic dystrophy
2017
Objective To evaluate sensitivity/specificity of the maximum relaxation rate (MRR) of inspiratory muscles, amplitude of electromyographic activity of the sternocleidomastoid (SCM), scalene (SCA), parasternal (2ndIS) and rectus abdominis (RA) muscles; lung function and respiratory muscle strength in subjects with Myotonic dystrophy type 1 (DM1) compared with healthy subjects. Design and methods Quasi-experimental observational study with control group. MRR of inspiratory muscles, lung function and amplitude of the electromyographic activity of SCM, SCA, 2ndIS and RA muscles during maximum inspiratory pressure (PImax), maximum expiratory pressure (PEmax) and sniff nasal inspiratory pressure (…
Repeatability of exhaled breath fingerprint collected by a modern sampling system in asthmatic and healthy children
2019
E-noses provide potential non-invasive metabolic biomarkers for diagnosing and monitoring pulmonary diseases. The primary aim of the present study was to assess the within-day and between-day repeatability of a modern breath sampling system (Pneumopipe® plus an array of e-nose sensors) in asthmatic and healthy children. The secondary aim was to compare the repeatability of the breath sampling system, spirometry and exhaled nitric oxide (eNO). Fifteen children (age 6-11 years) with asthma and thirty healthy children matched by age and gender (1:2 allocation) were recruited; of them, three healthy children did not complete the study. All measurements were collected twice during the baseline v…
Absence of lipid peroxidation as determined by ethane exhalation in rats treated with 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD).
1985
The exhalation of ethane is widely used as an indicator of in vivo lipid peroxidation. To test the hypothesis that lipid peroxidative events are involved in the toxicity of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD), we administered a lethal dose of TCDD (60 μg/kg), IP to male Sprague Dawley rats (160–180 g) and measured by gas chromatography the exhalation of ethane into the atmosphere of a closed all-glass exposure chamber. TCDD-treated rats exhaled only slightly more ethane than control rats at a single time point 7 days following TCDD administration. Since the exhalation of ethane is the net result of the endogenous production of the gas and its metabolic degradation, the latter was …
Hydrogen- and Methane-Based Breath Testing and Outcomes in Patients With Heart Failure
2019
Background: Recent evidence endorses gut microbiota dysregulation in the pathophysiology of heart failure (HF). Small intestinal bacterial overgrowth (SIBO) might be present in HF and associated with poor clinical outcomes. Lactulose breath testing is a simple noninvasive test that has been advocated as a reliable indicator of SIBO. In patients with HF, we aimed to evaluate the association with clinical outcomes of the exhaled hydrogen (H-2) and methane (CH4) concentrations through the lactulose breath test. Methods and Results: We included 102 patients with HF in which lactulose SIBO breath tests were assessed. Cumulative gas was quantified by the area under the receiver operating characte…
Porous materials applied to biomarker sensing in exhaled breath for monitoring and detecting non-invasive pathologies
2020
International audience; Overview of the use of porous materials for gas sensing to analyze the exhaled breath of patients for disease identification.The quantification of specific gases among thousand of VOCs (Volatile Organic Compounds) present in the human breath at the ppm/ppb level can be used to evidence the presence of diseases in the human body. The detection of these biomarkers in human exhaled breath through a noninvasive approach is an important field of research which is still attracting important attention to this day. A portable device working at room temperature and usable directly on exhaled breath samples is still a challenge requiring a sensing material with high performanc…