Respiratory physiology & neurobiology
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Respir Physiol Neurobiol · Jul 2013
Assessment of extravascular lung water by quantitative ultrasound and CT in isolated bovine lung.
Lung ultrasonography (LUS) and computed tomography (CT) were compared for quantitative assessment of extravascular lung water (EVLW) in 10 isolated bovine lung lobes. LUS and CT were obtained at different inflation pressures before and after instillation with known amounts of hypotonic saline. A video-based quantitative LUS analysis was superior to both single-frame quantitative analysis and visual scoring in the assessment of EVLW. ⋯ Mean CT attenuation was weakly correlated with EVLW density (r(2)=0.62) but strongly correlated with physical density (r(2)=0.99). When the effect of physical density was removed by partial correlation analysis, EVLW density was significantly correlated with video-based LUS intensity (r(2)=0.75) but not mean CT attenuation (r(2)=0.007). In conclusion, these findings suggest that quantitative LUS by video gray-scale analysis can assess EVLW more reliably than LUS visual scoring or quantitative CT.
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Respir Physiol Neurobiol · Jun 2013
Effect of nitric oxide inhalation on gas exchange in acute severe pneumonia.
Inhaled nitric oxide (NO) causes selective pulmonary vasodilatation and may improve gas exchange. The study was aimed to evaluate the acute effects of inhaled NO on pulmonary gas exchange in severe unilateral pneumonia, where hypoxemia results from increased intrapulmonary shunt. We studied 8 patients without preexisting lung disease (59±18 yr; 4M/4F) with early unilateral severe pneumonia and respiratory failure. ⋯ Inhaled NO caused a dose-dependent fall in pulmonary vascular resistance (by 12% and 21%, with 5 and 40ppm, respectively; p<0.01, each) and improvement of PaO2 (by 25% and 23%; p<0.05, each), owing to the reduction of intrapulmonary shunt (by 23% and 27%; p<0.05, each), without changes in the amount of perfusion to low V;A/Q; ratio alveolar units. Patients with greater baseline intrapulmonary shunt exhibited greater improvement in arterial oxygenation (r(2)=0.55, p<0.05). We conclude that low doses of inhaled NO improve pulmonary gas exchange in acute severe pneumonia.
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Camptocormia is defined as an abnormal flexion of the thoracolumbar spine of 45°, or more, that typically increases during walking or standing and completely disappears in the supine position. Camptocormia may occur in patients with Parkinson's disease; when it does, it is usually associated with greater disease severity. Respiratory complications, which may be secondary to abnormal chest function, are one of the most frequent causes of death in patients with Parkinson's disease. ⋯ The aim of this study was to evaluate the effect of camptocormia on lung function. Eleven patients with Parkinson's disease and camptocormia and ten age-matched healthy subjects underwent lung spirometry (in the standing position, inclining the trunk forward at approx. 45° and supine) measurement of arterial oxygen-hemoglobin saturation and heart rate. We found that Parkinson's disease with camptocormia is not associated with major clinical changes in lung volumes.
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Respir Physiol Neurobiol · Jun 2013
ReviewLife of neutrophil: from stem cell to neutrophil extracellular trap.
Neutrophils are one of the main types of effector cells in the innate immune system. Neutrophils play a major role in fighting diseases and are recruited almost immediately to sites of infection. ⋯ The latest role of neutrophils is neutrophil traps, which are a new component of innate anti-microbial immunity. Before neutrophils can effectively kill microorganisms they undergo a series of complex developmental processes.
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Respir Physiol Neurobiol · May 2013
Intermittent hypoxia increases melanoma metastasis to the lung in a mouse model of sleep apnea.
Obstructive sleep apnea (OSA) has recently been associated with an increased risk of cancer incidence and mortality in humans. Experimental data in mice have also shown that intermittent hypoxia similar to that observed in OSA patients enhances tumor growth. The aim of this study was to test the hypothesis that intermittent hypoxia mimicking OSA enhances lung metastasis. ⋯ Spontaneous and induced lung metastases were studied after subcutaneous and intravenous injection of B16F10 melanoma cells, respectively. Compared with normoxia, intermittent hypoxia induced a significant increase in melanoma lung metastasis. These animal model results suggest that intermittent hypoxia could contribute to cancer metastasis in patients with OSA.