Normal cardiovascular regulation requires intact baroreflex regulation. The efferent portion of the baroreflex arc, which is composed of parasympathetic and sympathetic nerves, is particularly important in this regard. Autonomic failure ensues when the efferent arc is interrupted. Neuronal degeneration within the brain or in the periphery,1,2 enzymatic defects in catecholamine synthesis,3 and a...

PURPOSE The bradycardia produced by pyridostigmine and physostigmine in an animal model of acute cardiac denervation was examined according to its relation to cholinesterase inhibition and sensitivity to block by cholinergic receptor antagonists. METHODS Cats were anaesthetised, vagotomised and propranolol-treated. Heart rate was continuously recorded. Erythrocyte cholinesterase activity of a...

A 52-year-old man developed diplopia, followed in 3 weeks by ptosis, more pronounced on the right, slight difficulty in talking, chewing, and swallowing, with nasal regurgitation, and mild weakness of the muscles of the neck and limbs. Family and past history were not contributory. There was bilateral ptosis, and the maximum width of the palpebral fissure on upward gaze was 8 mm on the right an...

We report on a case of refractory myasthenia gravis that was managed by using intravenous immunoglobulin. A 35-year-old Chinese woman with malignant thymoma-associated myasthenia gravis was treated by total thymectomy, followed by chemotherapy. Thirty months later, she developed respiratory failure and required mechanical ventilation for 2 months. A course of intravenous immunoglobulin was give...

CORRESPONDENCE MANAGEMENT OF CARBOXYHAEMOGLOBINAEMIA Sir,—Drs Vegfors and Lennmarken have demonstrated usefully how easy it is to be misled in the management of carbon monoxide poisoning [1]. Their case deserves further comment. Unfortunately, there is little information on the mechanism of cellular toxicity of carbon monoxide. Carbon monoxide binds to haem-containing enzymes such as cytochrome...

We describe a 47 year old woman with a 30-year history of generalized myasthenia gravis whose condition had been stable and well controlled on a combination of pyridostigmine and ephedrine until she presented. At this time she gave a 2 month history of weakness, nausea, vomiting and more recently intermittent confusion. Investigations confirmed both primary hypothyroidism and primary adrenal fa...