Biomedical subjects
Publications and source records attributed to R Abboud.
We report two cases of tricuspid valve endocarditis with related organisms (Enterococcus faecalis and Gemella morbillorum), some months after colonic operation. This association, without preexistent valvular pathology and without any other classical aetiology of tricuspid endocarditis, has only exceptionally been described.
We compared cardiac output determined simultaneously by two methods, the CO2 rebreathing technique and the thoracic electrical bioimpedance method (Bomed NCCOM-3 equipment). The studies were performed in duplicate in 11 healthy male subjects at rest and during three levels of steady-state exercise on a cycle ergometer at 60, 120, and 180 W. Cardiac output at 60 and 120 W was slightly lower (p less than 0.01) by the thoracic impedance method (12.2 +/- SE 2.2 and 15.7 +/- SE 3.5 L/min, respectively) than by the CO2 rebreathing method (14.0 +/- SE 2.1 and 17.9 +/- SE 3.0 L/min, respectively), suggesting a systematic bias between the two methods of measurement. However, if allowance is made for that bias, there would be acceptable agreement between the two methods at 60 and 120 W. Although the results were not significantly different between the two methods at rest and at 180 W, there was no acceptable agreement between the two methods probably because the CO2 rebreathing method at rest was more liable to show error due to the small arteriovenous CO2 difference, while the impedance method was less reliable at 180 W. Cardiac output by both methods correlated with O2 consumption, with the correlation being higher for cardiac output by the rebreathing method (r = 0.94) than for thoracic impedance (r = 0.88). The results suggest that the thoracic electrical bioimpedance method can be used for determination of cardiac output during mild or moderate levels of exercise in normal subjects.
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Computed tomography (CT) was compared with chest radiography in the assessment of disease severity in 27 patients with sarcoidosis. The CT scans and radiographs were each read twice by two independent observers. Disease extent was assessed on CT scans by visual scoring (0%-100% involvement of the lung parenchyma) and on radiographs by using an adaptation of the International Labour Office classification. The severity of parenchymal changes on the CT scan and on the radiograph was significantly correlated with the severity of dyspnea (r = .61 and .58, respectively; P less than .001), diffusing capacity (r = -.62 and -.52, P less than .01), and vital capacity (r = -.49 and -.51, P less than .01). Patients with predominantly irregular opacities had more severe dyspnea and lower lung volumes than patients with predominantly nodular opacities (P less than .05). The authors conclude that in patients with sarcoidosis, the radiographic and CT assessments of disease severity show similar correlation with clinical and functional impairment.
A six year follow up study of 750 aluminium smelter workers was undertaken to evaluate the relationship between the leucocyte count at the start of the study and the rate of decline in lung function. An inverse relationship between the leucocyte count and the forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) was present cross sectionally irrespective of cigarette smoking habit. The initial leucocyte count was also significantly related to the mean annual decline in FEV1 in smokers (p = 0.04) but not in former smokers or those who had never smoked. These observations suggest that the leucocyte count is a factor influencing the annual decline in FEV1 in smokers.
The effectiveness of nebulized anticholinergic and sympathomimetic regimens was evaluated in a double-blind study of 199 patients with acute airways obstruction. Patients were assigned to one of three treatment regimens according to a randomized schedule: 0.5 mg of ipratropium bromide, 1.25 mg of fenoterol hydrobromide, and 0.5 mg of ipratropium plus 1.25 mg of fenoterol. In 148 patients with acute exacerbations of asthma (mean one-second forced expiratory volume, 1.18 +/- 0.64 liters), all three regimens produced significant improvement in one-second forced expiratory volume (p less than 0.001). The greatest improvement followed treatment with the ipratropium-fenoterol combination (0.53 +/- 0.40 liters at 45 minutes; 0.57 +/- 0.51 liters at 90 minutes) and was significantly greater than that following either ipratropium alone (p less than 0.001) or fenoterol alone (p less than 0.05). In 51 patients with acute exacerbations of chronic obstructive pulmonary disease (mean one-second forced expiratory volume, 0.67 +/- 0.29 liter), each regimen produced significant improvement in one-second forced expiratory volume at both 45 and 90 minutes (for all, p less than 0.05), but there was no significant difference among the three treatment regimens. It is concluded that, in patients with acute asthma, combination therapy with sympathomimetic and anticholinergic agents is more efficacious than either one alone. In patients with acute exacerbations of chronic obstructive pulmonary disease, although either sympathomimetic or anticholinergic therapy provides bronchodilatation, no further benefit could be demonstrated from combination therapy.
Correlation between disease extent on computed tomographic (CT) scans and severity of clinical and functional impairment was obtained in 23 patients with usual interstitial pneumonia (UIP) by review of the clinical data, pulmonary function tests, chest radiographs, and CT scans. The CT scans and chest radiographs were each read twice by two independent observers. Disease extent was assessed on CT scans by a visual score (0%-100% involvement of the lung parenchyma) and on the radiograph by the International Labour Office classification. There was good intraobserver and interobserver agreement for both CT and radiograph scores (all r greater than or equal to .71). CT scans gave a better estimate of disease extent and showed more extensive honeycombing than did the radiograph. A significant correlation was found between the extent of disease as assessed with CT and the severity of dyspnea (r = .62, P less than .001), as well as between CT and impairment in gas exchange as assessed by the diffusing capacity (r = .64, P less than .001). There was poor correlation between disease severity as assessed with chest radiography and the clinical and functional variables (all r less than or equal to .39).
Serum chemotactic factor inactivator (CFI) activity was quantitated in 22 subjects with chronic airflow obstruction (CAO); 8 had normal antitrypsin levels (Pi M phenotype), 6 had intermediate antitrypsin deficiency (Pi MZ phenotype), and 8 had severe antitrypsin deficiency (Pi Z phenotype). We studied 19 healthy subjects with normal lung function as controls; 3 had Pi M and 6 had Pi MZ phenotypes. Subjects with CAO, irrespective of the alpha 1-antitrypsin (AAT) phenotype, had significantly lower CFI activity than the normal subjects; the lowest levels were found in those with CAO and Pi Z phenotype. Normal subjects with intermediate AAT deficiency and MZ phenotype had normal levels of CFI. The results suggest that deficiency of serum CFI may be important in the pathogenesis of chronic airflow obstruction, particularly in those with severe AAT deficiency.
The effect of breathing helium on maximal expiratory flow at 50 per cent of vital capacity (V50) was studied in 27 patients with asthma during remission and during induced bronchoconstriction. Nine patients gave a history of asthma induced by exercise; two had asthma due to timothy pollen allergy, and the remaining 16 had asthma due to exposure to western red cedar. Bronchoconstriction was induced by exercise in 10 patients, timothy pollen in 4 patients, methacholine in 4 patients, and red cedar in 16 patients. During remission, the increase in V50 with helium (deltaV50He) was greater than 20 per cent in 22 patients who were classified as responders; deltaV50He was less than 20 per cent in the remaining 5 patients, who were classified as nonresponders. There was a significant correlation between the severity of airway obstruction as measured by V50 and the response to helium, both during remission and during induced bronchoconstriction; however, there was no correlation between helium response and specific airway conductance. In general, patients who were responders during remission remained responders during induced bronchoconstriction, and nonresponders remained nonresponders, regardless of the method of challenge or the type of reaction (immediate verus late). There were a few exceptions in which a responder became a nonresponder during severe bronchoconstriction. The results of this study suggest that in most patients with asthma, the site of airway obstruction is likely to be in the large airways and, in most cases, remains constant in an individual asthmatic; however, an asthmatic who is a helium responder may become a nonresponder during severe bronchoconstriction.
Two patients with occupational asthma due to California redwood (Sequoia sempervirens) sawdust are described. They developed specific immediate and late asthmatic reactions after occupational-type exposure tests to this wood dust. In one patient the immediate asthmatic reaction was inhibited by pretreatment with disodium cromoglycate and atropine; however, the late asthmatic reaction was only partially inhibited by disodium cromoglycate and was not affected by atropine. Low molecular weight chemical compounds present in the redwood may be responsible for the symptoms.
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Explore the source record for details and available documents.