An electrophysiological investigation of skeletal muscles in polymyositis

An electrophysiological study has been made of the extensor digitorum brevis, thenar and hypothenar muscles in 25 patients with chronic and acute polymyositis. It was found a reduction of the number of functioning motor units in some patients with chronic polymyositis and only in one of those affected by acute polymyositis and only in one of those affected by acute polymyositis. The sizes of the surviving units suggested that the results could be explained in terms of a primary muscle involvement mainly in acute polymyositis, while in chronic polymyositis a combination of primary and neurogenic involvement of muscle fibers might take place.     

The tryptophan requirement of male and female broilers during the 4-7 week period

Studies with broiler type chickens were conducted to determine the minimum tryptophan requirement for maximum growth, optimum feed efficiency and molted body feather count for the 4-7 week period of growth for both male and females. Basal diets analyzed to contain 0.158, 0.157, and 0.147% tryptophan using analyzed tryptophan values of 0.09, 0.01, 0.31, 0.70, 0.40, and 0.46% for corn, gelatin, corn gluten meal, soybean meal, peanut meal-45, and peanut meal-50, respectively. Based on the regression equations for males, the calculated tryptophan requirement for maximum growth, optimum feed efficiency, and molted body feather count for the 4-7 week period is 0.179, 0.170, and 0.172%, respectively for 3300 Kcal. of M.E. per kg. of diet. When expressed as a function of energy, these requirements would be 0.054, 0.052, and 0.052% tryptophan per megacalorie of M.E. per kg. of diet, respectively. Based on the equations for females, the calculated tryptophan requirement for maximum growth, optimum feed efficiency, and molted body feather count is 0.173, 0.163, and 0.172%, respectively for 3300 Kcal. of M.E. per kg. of diet, respectively.     

Differential effects of intraventricular luteinizing hormone releasing hormone (LH-RH) and norepinephrine on electrical activity of the arcuate nucleus in the proestrous rat

Effects of intraventricular infusions of LH-RH and norepinephrine (NE) on the electrical activity of the arcuate nucleus were investigated in normally cycling proestrous rats. Under urethane anesthesia, recordings were made of amplitude-discriminated multiple unit spike activity and integated multiunit activity (MUA) in parallel with cortical EEG. Control infusions of saline (2 microliter, isotonic, pH 5.5) were ineffectual, but LH-RH (0.5 microgram) induced a significant increase in both multiunit spike activity and integrated MUA. While the response appeared to be continuous, statistical analysis revealed 2 phases: a quick rise which persisted for approximately 5 min, followed 15 min later by a longer-lasting elevation in activity. The onset of the 2nd increase corresponded with the attainment of peak values of pituitary LH output. Subsequent treatment with 20 microgram NE, on the other hand, resulted in a marked depression of activity. The fact that NE depresses arcuate neuronal activity at dose levels which cause the release of LH and that LH-RH increases activity within the same population of neurons, while possibly mediating an 'ultrashort-loop' negative feedback effect, suggest that this responsive component of the arcuate nucleus, perphaps the tuberoinfundibular dopaminergic system of neurons, is inhibitory to LH release.     

Voltage sensitivity of inhibitory postsynaptic current in Aplysia buccal ganglia

A single consistent luteolytic dose of 10 IU PMSG given on day 5 of pregnancy caused complete resorption of foetuses and placentae associated with a polyfollicular ovarian state in rats. Concomitant treatment with progesterone or prolactin given concurrently with PMSG was found to overcome the antifertility efficacy of PMSG and maintained the endocrine balance favouring pregnancy maintenance. It was postulated that the PMSG-induced ovarian polyfolliculogenesis might be responsible for luteolysis of the corpus luteum gravidarum.     

Role of immune complexes in the pathogenesis of atherosclerosis: age-related aspect

The experiments on 40 young and old rabbits which were given exogenous immune complexes (IC) for a month were made to study the changes in the blood levels of circulating IC (CIC), cholesterol and lipoproteins and their relation to the degree of atherosclerotic lesions to the vessels. The old animals that had low levels of minor CIC and insignificant transient increases in blood lipids were demonstrated to develop the same vascular atherosclerotic lesions as did the young animals that had higher levels of CIC and lipids. Some old animals retained a high immunological responsiveness (high CIC levels), which was accompanied by high incidence rates and extent of aortic lipid lesions. The findings make us conclude that the role of IC in atherosclerotic responsiveness increases with age.     

Internal ophthalmoparesis: an uncommon complication of varicella, a common disease

Two cases are represented with ocular complications after varicella. In one case the complication was diagnosed as internal ophthalmoparesis and in the second patient the complication could be the same; at any rate an iridoplegia was present. From the cases presented in the literature we found that there seems to be a predilection for males to contract this type of ocular complication. The association of this complication and meningo-encephalitis is rare. Recovery of the pupillary reactions and accommodative power is almost never complete. The interesting observation that decrease in cell-mediated immunity but not in humoral immunity decides whether the clinical disease will manifest itself as herpes zoster or varicella is brought forward.     

Diagnosis, pathogenesis, and treatment of sarcoidosis

Sarcoidosis is a commonplace multisystem disorder characterized by the presence of noncaseating granulomas. Although the clinical syndrome of the disease is recognized throughout the world, the pragmatic understanding of its diagnosis and management remains poorly understood and controversial. Much of the frustration experienced in elucidating its pathogenesis is directly related to our inability to find the cause of the disease. This review provides a brief and practical discussion of the diagnosis, pathogenesis, and concept of disease activity. It also recommends guidelines for management based on available clinical, immunologic, and radiologic information enhanced by our experience at the University of Southern California during the past 30 years.