摘要:

The effect of pulmonary artery hypertension on right-ventricular performance in patients with chronic obstructive pulmonary disease (COPD) is unclear. Decreased values of right-ventricular ejection fraction (RVEF) have been reported, but most patients with stable COPD are not in cardiac failure and have normal or even increased cardiac outputs. We therefore hypothesized that RVEF may be afterload dependent, and thus a poor parameter of cardiac function, and that right-ventricular contractility may be normal even in COPD patients with pulmonary hypertension. We therefore studied 24 COPD patients using a combined hemodynamic and radionuclide approach. RVEF and thermodilution stroke volume index were measured simultaneously at rest in all 24 patients and also during bicycle ergometry in 9 patients. We then calculated end-diastolic and end-systolic volume indices and derived right-ventricular systolic pressure-volume relations in all and the slopes (E) of the pressure-volume line in 9 patients. RVEF was normal in COPD patients without pulmonary hypertension, but was reduced in those with pulmonary hypertension. A strong inverse linear relation between RVEF and mean pulmonary artery pressure (r = -0,73; p < 0.001) and pulmonary vascular resistance (r = -0.69; p < 0.001) could be demonstrated, indicating RVEF to be highly afterload dependent. Right-ventricular end-diastolic volume index was significantly higher in patients with pulmonary hypertension, indicating increased preload as the major mechanism to maintain adequate stroke volume in the face of an increased afterload. Right-ventricular end-systolic pressure-volume relations, a good parameter to define right-ventricular contractility independent of systolic loading conditions, were not different between COPD patients with or without pulmonary hypertension, nor did the slopes of the pressure-volume lines in the 9 patients studied during exercise show any difference. From these data we conclude that (a) RVEF is a poor indicator of overallright-ventricular function; (b) right-ventricular contractility is well preserved in stable COPD patients; (c) the major mechanism of maintaining stroke volume in the face of increased right-ventricular afterload seems to be preload augmentation.

ISSN:0025-7931    

DOI:10.1159/000195389

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Based on the hypothesis that blood platelets contribute to the pathogenesis of hypoxemic pulmonary hypertension in patients with chronic obstructive pulmonary disease (COPD), the effect of a prolonged treatment with dipyridamole, a platelet-inhibiting drug, on hypoxemic pulmonary hypertension was evaluated in a double-blind cross-over study. Eight patients with COPD, pulmonary hypertension [mean systolic pressure 52.2 ± (SD) 9.7 mm Hg; mean diastolic pressure 25.8 ± (SD) 6.8 mm Hg] and shortened platelet regeneration time [mean 5.2 ± (SD) 1.2 days] received, in a cross-over random sequence, the following two 3-month treatments: (a) dipyridamole 100 mg and acetylcysteine 100 mg every 6 h; (b) acetylcysteine, 100 mg every 6 h. Dipyridamole significantly prolonged the platelet regeneration time [mean 6.5 ± (SD) 1.0 days; p < 0.05]. There was no significant effect on diastolic pulmonary pressure. However, systolic pressure was significantly (p < 0.05) lower after dipyridamole [46.8 ± (SD) 16 mm Hg] than after placebo [56.1 ± (SD) 14 mm Hg]. These results suggest that dipyridamole can slow the progression of hypoxemic pulmonary hypertension in patients with

ISSN:0025-7931    

DOI:10.1159/000195390

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

One hundred and fifty-six German, Italian and Polish patients with confirmed aspirin-induced asthma underwent open oral challenges with increasing doses of tartrazine up to 25 mg. All positive challenges were repeated under double-blind conditions. Only 4 of 156 patients (all Polish) had positive reactions in a double-blind test, as evidenced by a fall in FEV1 25% from baseline and corresponding clinical symptoms. Sixty-five patients who tolerated 25 mg tartrazine well received 50–3,000 mg tartrazine and none showed adverse reactions. Thus, intolerance to tartrazine appears to be rare among Central-European and South-European patients with aspirin-induced asthma, its frequency amounting to about 2.6

ISSN:0025-7931    

DOI:10.1159/000195391

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

The role of extracellular Na+ and Ca++ in cooling-induced contraction (CIC) was studied in guinea pig trachealis muscle. Tracheal preparations were tested in Krebs-Ringer bicarbonate (KRB) solution and then in either: (1) a low Na+ sucrose KRB, (2) KRB plus amiloride, a sodium channel blocker, or (3) KRB plus nifedipine, a calcium channel blocker. When the trachealis muscle was cooled from 37 to 20 °C in KRB, the value of the isometric tension increased on average by 25% of the maximal tension induced by acetylcholine; however, when the tissue was tested in the low Na+ sucrose KRB or the KRB containing amiloride, CIC was totally prevented. In the presence of nifedipine the mean value of CIC was only 10% of the acetylcholine-induced contraction, which was also observed not to be affected by extracellular Na+ or Ca++; whereas the KCl-induced contraction was affected by Ca++ but not by Na+. The results suggest that rapid cooling of the smooth muscle cells causes an increase in sodium conductance and a decrease in the activity of the Na+-K+ pump, resulting in membrane depolarization. During depolarization a significant quantity of Ca++ enters the cell, contributing to the magnitude of CIC

ISSN:0025-7931    

DOI:10.1159/000195392

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Sixty-eight asthmatics participated in a dose-finding study on bambuterol, a terbutaline prodrug, administered once every evening. Bambuterol administrations of 0.185, 0.270 and 0.400 mg/kg gave effective and long-lasting bronchodilation, for at least 24 h, with the two higher doses probably close to the maximal effect of the drug. Bambuterol 0.400 mg/kg was associated with more adverse effects than bambuterol 0.185 mg/kg. The side effects were those expected in oral β2-agonist treatment and mainly experienced by patients who had not been on oral β2-agonists before. The most favourable of the investigated doses was found to be 0.270 mg/kg. It can not be excluded, however, that a somewhat lower dose may still be as beneficial. This will be investigated in forthcoming studie

ISSN:0025-7931    

DOI:10.1159/000195393

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Seventy-six chronic bronchitis patients were studied in order to determine the possible presence of disorders in their systemic defense mechanisms. No significant difference in lymphocyte subsets, in serum immunoglobulin and complement component (C3 and C4) levels was found in chronic bronchitis patients compared to normal adult controls. Skin tests for delayed hypersensitivity revealed a high frequency (39%) of hypoergic patients (with 1 -2 positive reactions) in comparison to normal subjects.Altered values of many functional properties of both neutrophils and monocytes were demonstrated. The percentage of patients with intermediate (between 1 and 2 SD below the mean of controls) and defective (lower than 1.96 SD) values of chemotaxis, phagocytosis index and Candida killing was about 50%. Phagocytosis frequency and nitroblue tetrazolium reduction frequency were less frequently impaired.

ISSN:0025-7931    

DOI:10.1159/000195394

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Respiratory cilia of the bronchial mucosa from a 5-year-old boy with clinical evidence of classical Kartagener’s syndrome (situs inversus, bronchiectasis and sinusitis) were first examined by means of transmission electron microscopy for identification of the axonemal defects described as typical for primary ciliary dyskinesia (PCD). Additional oscillography was performed on the cilia in vitro, which showed absence of a coordinated ciliary beat frequency. After clear classification of the case as PCD, a freeze-fracture examination of the respiratory cilia was performed, which revealed a higher density of intramembrane particles on the outer fracture face (E-face) than on the inner fracture face (P-face). The results were discussed with regard to probable pathogenetic aspects on PC

ISSN:0025-7931    

DOI:10.1159/000195395

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

The toxic effects of the free fatty acids (FFA) are responsible for the initiation and the clinical manifestations of the fat embolism syndrome (FES). Serum albumin binds to the FFA and by producing atoxic compounds it has a therapeutic effect on the syndrome. In this study we applied bovine albumin to 48 Sprague-Dawley rats which were previously submitted to intravenous infusions of FFA solutions (oleic, palmitic, stearic). The histopathologic lesions observed in their lungs were compared to those of 50 control animals suffering from the FES. The administration of 0.5% bovine albumin solution intravenously and 0.2% intraperitoneally, especially when it was synchronous to the FFA infusion and not metachronous, resulted in substantial and statistically significant therapeutic effects.

ISSN:0025-7931    

DOI:10.1159/000195396

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

This study was designed to compare spirometers used for human testing and to determine whether the results obtained by different spirometers meeting the American Thoracic Society (ATS) requirements are interchangeable. Water-sealed spirometer (Harvard), dry bellow wedge spirometer (Vitalograph) and computerized pneumota-chograph (Gould), all of them satisfying the ATS recommendations were compared. Forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), forced expired flow between 25 and 75% of FVC (FEF25-75%) and 100 FEV1/FVC(FEV1%) were selected for comparative analysis. Measurements of these parameters were carried out on a total of 40 healthy volunteers of mixed nationalities. The Vitalograph values for FVC, FEV1 and FEV1% were significantly higher than those of the water-sealed spirometer (Harvard), but were closely similar to the values obtained by the Gould computerized pneumotachograph. Our results thus do not support the interchangeability of different spirometers and stress the importance of biological standardization of spirometers against each other.

ISSN:0025-7931    

DOI:10.1159/000195397

出版商:S. Karger AG    

年代:1988

数据来源: Karger

ISSN:0025-7931    

DOI:10.1159/000195398

出版商:S. Karger AG    

年代:1988

数据来源: Karger