Surfactant as an airway smooth muscle relaxant.

A variety of clinical and experimental evidence indicates that surfactant may be important in the pathogenesis and treatment of asthma. The purpose of this study was to determine the pharmacologic effect of pulmonary surfactant and its major lipid and protein constituents on bronchial smooth muscle. First-generation bronchi from male Sprague-Dawley rats were contracted with methacholine and exposed to two kinds of surfactant: whole rat surfactant and two bovine surfactant extracts in clinical use. The latter lack the hydrophilic surfactant-associated proteins (SP)-A and SP-D. All the surfactants relaxed the rat bronchi in a concentration-dependent manner; however, whole rat surfactant was more potent than the bovine extracts. Both surfactant lipids and SP-A contributed to the bronchial relaxation. The relaxation response produced by the highest concentration (0.5 mg/ml) of whole rat surfactant was equivalent to that caused by substance P (5 microM) and approximately half of that caused by 1 microM isoproterenol. The relaxation response was epithelium-dependent and blocked by indomethacin but not by N-omega-nitro-L-arginine methyl ester. We conclude that surfactant can relax airway smooth muscle directly via a prostanoid-mediated, epithelium-dependent process that does not involve nitric oxide synthase.

[Demand for consultations at the Emergency Service of the "Dr. José Horwitz B" Psychiatric Institute in Santiago, Chile: comparison between 1988 and 1994]. / Demanda de consultas al Servicio de Urgencia del instituto Psiquiátrico "Dr José Horwitz B" de santiago: comparación entre 1988 y 1994.

BACKGROUND: In the last decade, there have been changes in the prevalence of specific psychiatric disorders. AIM: To study the diagnoses and demographic features of patients consulting the emergency wards of a public psychiatric hospital in Santiago during 1994 as compared with those of patients consulting in 1988. MATERIALS AND METHODS: A random sample of 439 patients charts, corresponding to 3% of all consultations during 1994, were analyzed. The results were compared with consultations during 1988, analyzed in a previous study. RESULTS: During 1994, patients were older, came alone to the emergency wards and consulted during the night with greater frequency than during 1988. In both years psychosis were the main cause of consultation. Compared to 1988, during 1994 there was an increase in the frequency of affective disorders (16 and 12% of all consultations respectively) and substance abuse (15 and 3% respectively). CONCLUSIONS: The increase in consultations due to affective disorders and substance abuse in 1994 is in accordance with changes in the epidemiological profile of psychiatric disorders in Santiago.

[Acute poisoning with thioridazine]. / Akute Intoxikationen mit Thioridazin.

OBJECTIVE: As previous single case reports have indicated that acute poisoning with thioridazine can be potentially dangerous, an investigation was undertaken to find out whether the risk of severe poisoning in adults and children can be judged from the amount of the drug that has been taken. PATIENTS AND METHODS: In a case-control study 202 medical notes of 202 patients were analysed (141 adults, aged 16-82 years; 61 children, aged 0.3-15 years) in which thioridazine was the only potentially harmful substance taken, the precise amount swallowed was known and the drug was the certain or probable cause of the signs. 30 children were excluded from the study, because their body weight was not known. RESULTS: Mild thioridazine poisoning was characterized by somnolence, tremor, ataxia and dysarthria. The severity of the poisoning and the degree of disorder of consciousness correlated significantly with the amount of thioridazine taken. Severe intoxication with coma and ventricular arrhythmias was observed at a dose of 2 g and more. While the disorder of consciousness completely regressed in the first 24 hours, in a few of the patients the cardiac arrhythmias persisted for up to 28 hours after the drug intake. Charcoal administration seemed to influence the course favourably. CONCLUSION: Prolonged, intensive care supervision and treatment are essential if more than 2 g thioridazine have been swallowed. In addition to standard treatment with gastric lavage charcoal should be given as early as possible to limit absorption.