No abstract is provided for this article.
Tolerance to the direct bronchodilator effects of β2-agonists does not appear to occur in asthma. However, it is not known whether this is true for the nonbronchodilator effects of these agents, which protect the airways against bronchoconstrictive stimuli.
To describe the characteristics of patients undergoing coronary angioplasty (PTCA) over the past 20 years and the outcome after 1 and 5 years.Prospective follow-up study.All patients who underwent a first PTCA in the Thorax centre of the Erasmus Medical Centre in Rotterdam during the period from 1 September 1980 through 30 November 1985 (group I) were compared with all patients who likewise underwent such a first PTCA during the period between 1 September 1995 and 31 December 1996 (group II). Data on the patients, the operations, any reoperations and the mortality were obtained from patient records, general practitioners and municipal archives. Cumulative percentages of survival and of not having rePTCA or coronary artery bypass surgery (CABG) were analysed by using the Kaplan-Meier-method.Group I consisted of 856 patients and group II of 840 patients. The percentage of males decreased over the years from 80% to 69%. The average age increased from 56 to 60 years; the oldest patient in group I was 75 years and the oldest in group II was 87 years. The percentage of patients with multivessel disease increased from 36% to 44%. Stent implantation occurred in 55% of the patients in group II (0% in group I). The necessity for urgent CABG due to unsuccessful PTCA decreased from 9.4% to 1%. After 1 year, the percentage of coronary revascularisations was 28.8% in group I and 22.6% in group II (p = 0.01). The perioperative mortality and the 5-year survival were not significantly different in the two groups (group I: 1.3% and 90%; group II: 2.4% and 88%, respectively). For both groups, higher age, a smaller ejection fraction, more extensive vascular disease and no treatment with statins were independent predictors of a higher mortality after 5 years. In group II, renal function disorders were the most important predictor of higher mortality.
Nitric oxide (NO) is produced by many cells within the respiratory tract and endogenous NO may play an important signalling role in the physiological control of airway function and in the pathophysiology of airway diseases [1–3]. All three isoforms of NO synthase (NOS) exist within the respiratory tract [4–6]. The endothelial constitutive isoform (eNOS) is localised to bronchial endothelial cells and to epithelial cells [7] and the neuronal isoform (nNOS) to parasympathetic nerves and to epithelial cells [8, 9]. Inducible NOS (iNOS) may be localised to several cell types, including epithelial cells and macrophages [10–12] and may be expressed even in the normal human respiratory tract (Fig. 1).
Summary Circulating catecholamines are not abnormally elevated in asthmatics. The normal circadian fall in circulating adrenaline at night may contribute to nocturnal wheezing by facilitating release of bronchoconstrictor mast cell mediators. Asthmatics who develop exercise‐induced wheezing show an impaired catecholamine response to exercise which may facilitate mediator release during exercise. Endogenous catecholamines in asthma may therefore play a modulatory role on the release of mast cell mediators.