摘要:

Maximum inspiratory and expiratory pressures were measured at residual volume, total lung capacity, and functional residual capacity in 45 morbidly obese patients who on average weighed 183% of their predicted weights. The pressures were compared to determinations made in 25 subjects of similar age whose mean weight was 99% of predicted. For both men and women, pressures generated by control subjects tended to be higher than those produced by obese patients but the differences were not statistically significant. The mean vital capacity and total lung capacity were also similar in the 2 subject groups. The results indicate that despite working constantly against a less compliant chest wall, obese patients do not increase their capacity to generate maximal respiratory pressures

ISSN:0025-7931    

DOI:10.1159/000195504

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

We measured both tracheal sounds and forced expiratory flows simultaneously in 20 normal subjects and 4 patients with stenosis of the main bronchus. Spectral analysis of the tracheal sounds revealed development of discrete line spectra, the frequencies of which ranged between 488 and 942 Hz. There was a positive correlation between these frequencies and the peak flows (r = 0.601). We speculate that the origin of these line spectra are vortices rather than the vibrations of the wall. It is postulated that the pressure drops caused by vortices make the airways more susceptible to collapse and may lead to flow limitation

ISSN:0025-7931    

DOI:10.1159/000195505

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

A 22-year-old black male presented with progressive dyspnea, a nonproductive cough, and new skin lesions. He was severely hypoxic, and had a severe restrictive defect on pulmonary function testing. A 2-cm lytic defect was noted on skull radiographs. A lung biopsy demonstrated pulmonary fibrosis. A biopsy of a skin lesion was consistent with a diagnosis of multifocal eosinophilic granuloma, or disseminated histiocytosis X. The case presents several unusual features of this uncommon disorder

ISSN:0025-7931    

DOI:10.1159/000195506

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

To quantitatively examine and compare the effects of β-adrenergic blockade on ventilation, we studied 20 healthy volunteers during inhalation of room air and at steady state CO2 (2.0, 4.4, 6.0%) following a single oral dose of bupranolol (vs. placebo). During room air breathing, minute ventilation (VE) and mean inspiratory flow (Vτ/Tι) were significantly reduced after β-blockade with a concomitant increase in blood PaCO2 (p < 0.01). The timing factor Tι/Ttot and mouth occlusion pressure P0.1 remained unchanged. These differences were, as shown from calculated effective alveolar ventilation, mainly attributed to a decrease in physiological dead space ventilation following β-blockade. With a stepwise increase in FICO2, the difference in PaCO2 between placebo and bupranolol tended to approach zero, whereas VE and Vτ/Tι remained significantly lower during β-blockade (P < 0.05). In contrast, no difference existed in P0.1 between bupranolol and placebo. We suggest that (1) respiratory drive assessed by P0.1 is unaffected by β-blockade and (2) mean inspiratory flow depends also on CO2 elimination characteristics, which are influenced by

ISSN:0025-7931    

DOI:10.1159/000195507

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

In 12 normal healthy males, the effect of preventing augmentation in tidal volume (Vτ) on the heart rate (HR) was examined during isocapnic progressive hypoxia. The amount of diminished tidal volume (ΔVT) was 0.61 ± 0.36 liters from the maximal Vτ value attained in the free breathing hypoxia. Hypoxic HR response in terms of arterial oxygen saturation (SaO2)/HR response slope (ΔHR/ΔSaO2) was significantly decreased from the free to controlled breathing (p < 0.05). The effective Vτ range for eliciting such a HR change appeared to be more than 1,000 ml as has been demonstrated in the reflex on ventilation in humans. However, the magnitude of ΔHR/ ΔSaO2 decrement was not significantly correlated with ΔVT, suggesting that the command signal from the higher nervous center interfered with the expected response. Contrary to the HR response, the hypoxic ventilatory and occlusion pressure responses were not significantly influenced by the controlled breathing. We conclude that the hypoxic HR response is significantly depressed by the diminished Vτ

ISSN:0025-7931    

DOI:10.1159/000195508

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Pulmonary vasoactivity of several biochemical components produced or stored in platelet was the justification for the study of pulmonary artery pressure in fawn-hooded rats (FHR) with hereditary platelet storage pool deficiency. Anesthetized (pentobarbital 35 mg kg-1 i.p.) FHR had higher right ventricular systolic pressure compared with normal Wistar rats (NWR) matched in sex and age (57.7 ± 6,8 vs. 34.8 ± 1.2 mm Hg; p x + 2 SD of NWR) was 68% among FHR. A significant difference was recorded between FHR and NWR in the relative weight of the right ventricle (0.092 ± 0.021 vs. 0.048 ± 0.001 g/100 g; p < 0.05). Rise in pulmonary artery pressure in FHR after 4 weeks of normobaric hypoxia was found to be comparable to that seen posthypoxically in NWR. Morphological consequences of pulmonary hypertension, ranging from moderate medial hypertrophy of small arteries to muscularization of pulmonary arterioles, were recorded in about 50% of FHR with increased pulmonary artery pres

ISSN:0025-7931    

DOI:10.1159/000195509

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

The influence of oral corticosteroid therapy (7.5 and 15 mg prednisolon/ day for 8 days) on basophil releasability by antigens was investigated in a series of 16 patients with chronic obstructive airway disease. A significantly smaller histamine release was observed after the treatment. Different types of releasing curves were observed which mostly persisted after treatment Glucocorticosteroids are among the most effective therapeutic agents available for a variety of acute and chronic inflammatory diseases [Schleimer et al., 1981; Daeron et al., 1982]. In asthma, increased reactivity is not limited to the airways, but also exists in other systems such as mediator-releasing cells [Neijens et al., 1979]. In this study we attempted to determine whether oral corticosteroid therapy influences human basophil releasability.

ISSN:0025-7931    

DOI:10.1159/000195510

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Because of the prevalence of supine posture and sleep deprivation in both health and disease, we wondered how each of them influences prolonged maximal voluntary ventilation (MVV). Accordingly, we compared 12-second, 1-min, and 10-min isocapnic MVV supine with that measured in the upright posture in 8 healthy subjects. MVV decreased 6–10% supine, independent of test duration (p < 0.01). Although end-expiratory lung volume was 0.47 liter lower during supine resting breathing (p < 0.001), end-expiratory lung volumes during short-term MVV maneuvers were identical. To investigate any additional effect on MVV due to sleep loss, 12 healthy subjects performed 12-second, 1-min, and 30-min isocapnic MVV maneuvers in the supine position, either after normal sleep or after a 24-hour sleepless period. Sleep deprivation reduced MVV by 7–14%, again independent of test duration (p < 0.05). Sleep loss also reduced the ventilation chosen to represent a submaximal (75%) breathing effect (p = 0.05), and it increased subjective ratings of fatigue and confusion (p < 0.01). We conclude that supination and sleep deprivation together decrease both short- and long-term MVV by nearly 20%, with impairment of supination not caused by lung volume changes, and with the sleep loss effect occurring in tandem with a rise in the subjective assessment of breathing ef

ISSN:0025-7931    

DOI:10.1159/000195511

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Inflammatory mediators influence mucociliary transport function in the lung, which may be dependent on the beating of the underlying cilia. To determine whether a nonsteroidal anti-inflammatory drug affects this function, and, if so, what is the mechanism action, we examined the effect of indomethacin on ciliary beat frequency (CBF) of cultured rabbit tracheal epithelial cells by a photoelectric technique. Addition of indomethacin dose-dependently enhanced CBF without any ciliary disco-ordination, the maximal increase and Km being 26.5 ± 4.8% (mean ± SE, p < 0.001) and 6.8 × 10-7M, respectively. Pretreatment of tissues with nordihydroguaretic acid (10-5M), an inhibitor of the lipoxygenase pathway, did not change the baseline CBF, but inhibited the response of CBF to 3 × 10-6M indomethacin (p < 0.01). These results suggest that indomethacin may accelerate mucociliary clearance through the augmentation of ciliary motility and that this ciliostimulation may be mediated by leukotrienes produced by activation of the lipoxygenase pathway of arachidonic acid metabo

ISSN:0025-7931    

DOI:10.1159/000195512

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Structural and functional changes in lung tissue of mice fed with β-amino-propionitrile fumarate, L-3-cis-hydroxyproline, and L-4-cis-hydroxyproline. We fed 0.1% solutions of 3-cis-hydroxyproline (3cisHP), 4-cis-hydroxyproline (4cisHP) or β-aminopropionitrile fumarate (βAPN) to 5-week-old mice for 1 month and studied the effect of each of these substances on the lung function and structure. Compared to control animals the compliance of the respiratory system in the mean was increased by 3–15% in the mice fed βAPN or 3cisHP, and decreased by 2–8% in the mice fed 4cisHP. On electron microscopial examination no overt morphological changes were detectable although as proven by biochemical analysis 3cisHP and 4cisHP were incorporated into the collagen of the mice who received these substances. We conclude that the effect of substances interfering with the normal production of collagen molecules depends on the kind of collagen affected and on the rate of collagen

ISSN:0025-7931    

DOI:10.1159/000195513

出版商:S. Karger AG    

年代:1988

数据来源: Karger