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SUMMARY The antiarrhythmic action of the beta-blocking drug, acebutolol, was evaluated in patients with frequent premature ventricular contractions (PVCs). In the 12 hours following administration of a single 300 mg oral dose, 8 of 10 patients showed a greater than 50% reduction in PVC frequency, and statistical analysis indicated that PVC reduction persisted for 10 hours after the single dose. Analysis of plasma concentrations of acebutolol and an acetyl metabolite indicated that after single oral doses the plasma concentrations of the metabolite exceed those of unchanged acebutolol.A POSITIVE CORRELATION between the presence of frequent premature ventricular contractions (PVCs) and the subsequent incidence of sudden cardiac death has been observed,1' 2 particularly in patients with coronary artery disease.8 3 It is a reasonable though unproven hypothesis that suppression of these ectopic impulses would result in a decrease in the incidence of sudden death in these patients. Testing of this hypothesis has been limited to date primarily by the lack of antiarrhythmic drugs suitable for chronic administration.6 7 Such drugs should be effective, free of toxicity, and have properties that allow administration on a convenient dosage schedule which permits patient compliance. The development of such agents is currently the goal of extensive laboratory and clinical investigation.Acebutolol, (M&B 17803A) (±)-1-(2-acetyl-4-n-butyramido-phenoxy)-2-hydroxy-3-isopropylaminopropane ( fig. 1) is a new, relatively cardioselective beta-adrenergic antagonist. Acebutolol blocks the myocardial beta-receptors by a competitive inhibition and has a weak sympathomimetic action.8 In intravenous studies, it has approximately one-seventh the beta-blocking potency of propranolol.9 In addition, it has the membrane-stabilizing, so-called "quinidine-like" property found in propranolol but not in practolol.'0 In experimental arrhythmia studies, differences from both propranolol and practolol have been noted1' which have potential clinical utility, and preliminary clinical arrhythmia studies are promising.'2 The drug has less effect on the beta-receptors of bronchial smooth muscle than propranolol and has been administered to asthmatics.'8 Acebutolol has also been used successfully in When patients were studied during periods of 300 mg doses every 8 hours, eight of 11 showed a 70% reduction in PVC frequency, and analysis showed that the therapeutic effect was present throughout the 24-hour monitoring period. Acebutolol slowed the heart rate and prolonged the PR interval without affecting the QT interval. Significant clinical or laboratory toxicity was not encountered. In the small group studied, acebutolol was found to be safe and effective for shortterm administration to patients with frequent PVCs and possessed a relatively long duration of antiarrhythmic action.of acebutolol to a group of ambulatory patients with frequent PVCs. Methods Patient PopulationTwelve patients, 11 men and one woman, participated in the study after giving written...

Background This paper examines an important relationship created in the process of regulating major chemical and petrochemical installations in two towns: Grangemouth in Scotland, and Ludwigshafen in Germany. These are towns very different in size, and which have recently experienced very different economic fortunes. Nonetheless, they share the common characteristic of a long association with chemicals and petrochemicals, and have each been dominated by a single corporation: BP has been based in Grangemouth since 1924; BASF originated in Ludwigshafen in 1865, and the town remains its global headquarters. The relationship we examine here is that between environmental regulators and residents: that is, between the various regulatory and planning authorities responsible for the safety of the industries in both places, and the residents who make up the wider public of each town and who have the most direct stake in the efficacy of the regulators' work. We thus explore the local context within which environmental risks and their regulation have been evaluatedötacitly and informally as much as through any formally institutionalised arrangements öin each town. Our interest has been in local public commentaries on the regulation of each town's industry, in the