Symptomatology Variables Research Articles

Neuroleptic dose and schizophrenic symptoms. A survey of prescribing practices.

A study was conducted to survey the prescribing practices of neuroleptic doses in 100 consecutively hospitalized DSM-III-R schizophrenic patients. The relationship between doses and clinical and symptomatological variables was subsequently analyzed. Patients were evaluated through the Positive and Negative Syndrome Scale (PANSS). The peak mean dose in chlorpromazine equivalents was 1290 (range 250-7200). Haloperidol was the most commonly employed neuroleptic (67 patients). Neuroleptic doses were correlated with excitement, suspiciousness, hostility, uncooperativeness and poor impulse control. The neuroleptic doses administered in our hospital were similar to those found in other survey reports but higher than those recommended by the controlled dose-response studies. The correlation found between neuroleptic doses and symptoms of disruptive behavior suggests that we employed high-dose practices to treat the disruptive symptoms of schizophrenia. We concluded that it is useful to distinguish between the neuroleptic doses required to control the psychotic episode and those to treat the disruptive behavior.

What have cognitive deficits to do with schizophrenic symptoms?

This paper considers possible relationships between cognitive deficits and symptomatology in schizophrenia. It is argued that a combination of defective filtering and slowness in response selection results in a state of information overload in acute schizophrenia. The methods by which normal subjects adapt to experimenter-induced overload may therefore be relevant to aspects of schizophrenic behaviour. The considerable intra- and inter-subject variability in symptomatology of schizophrenic patients may represent differeing adaptations to similar cognitive disturbance, such secondary abnormalities being prominent in chronic patients. Sections of the literature on acute-chronic differences are consistent with such a formulation, although one cannot infer intra-individual change from cross-sectional studies; there is a clear need for longitudinal investigations in this area. The preferred method of adaptation will be dependent on the severity of overload, the environment, and personality factors independent of the psychosis. The implications for the modification of schizophrenics' behavioural abnormalities by operant procedures are discussed.

A comparison of the virulence for European rabbits (Oryctolagus cuniculus) of strains of myxoma virus recovered in the field in Australia, Europe and America.

Strains of myxoma virus associated with a case-mortality rate in wild rabbits of 90—95% can be distinguished from those associated with a case-mortality rate of more than 99% by the use of a standardized virulence test carried out in groups of five laboratory rabbits, and tests carried out on laboratory rabbits are closely correlated with the results obtained with Australian wild rabbits. The test, which attempts to mimic natural mosquito transmission, consists of the intradermal inoculation in one site of about 5 rabbit-infectious doses of the virus, and the subsequent observation of the rate of progress of clinical symptoms and ultimate fate of the rabbit. The mean survival time provides a figure which allows satisfactory classification of all known myxoma virus strains into one of four grades of virulence, very attenuated strains being recognized by their low case-mortality rates.Using this test, 92 strains of myxoma virus have been compared. These comprised 6 laboratory strains, 62 strains recovered from Australian wild rabbits or from wild caught mosquitoes, between February, 1951 and March, 1955, 19 strains recovered from naturally infected rabbits in Europe between October, 1953 and August, 1955, 3 strains from South America, and 2 from California. Eight types have been described and illustrated, differentiation being based on their virulence and the clinical picture of the disease they cause in laboratory rabbits. The differences are summarized in Text-fig. 2. Four of the virus types produce recognizably different pocks on the chorioallantois of developing chick embryos.In Australia the repeatedly introduced standard laboratory strain of virus has been replaced by a moderately virulent strain, which appears to be better adapted for survival than either the highly virulent standard laboratory strain, or less virulent variants of which only a few had been recovered up to 1955. Strains of the type dominant in 1953–55 have appeared independently in many widely separated parts of Australia. Examination of these attenuated variants by pure clone techniques showed that the variability in symptomatology associated with them is not due to a mixture of virus strains, but to the expression of differences in innate resistance of the host animals which are obscured by the overwhelming virulence of the highly virulent strains.Only one introduction of a different strain of virus was made in Europe. All field strains recovered during the first two years after the introduction were of high virulence, but a few attenuated strains appeared in 1955, and they have since become widespread. One of them appears to be a relatively stable mixture of a highly virulent and a greatly attenuated strain.The collection of the large numbers of strains of virus described in this paper has been made possible only by the generous collaboration of many people. In Australia we would like to acknowledge the great help afforded us by Mr F. N. Ratcliffe, officer-in-charge of the Wildlife Survey Section, Commonwealth Scientific and Industrial Research Organization and his officers, especially Messrs J. H. Calaby, G. Douglas, A. L. Dyce, B. V. Fennessy, E. W. Lines, K. Myers, R. Mykytowycz, W. E. Poole and E. Waterhouse. Messrs B. D. Robinson and T. Pearce of the Lands Department of Victoria have also provided us with specimens, as have Mr G. Edgar, Director of the Veterinary Research Station, Glenfield, New South Wales, Dr D. Surrey Dane of the Institute of Medical and Veterinary Science, Adelaide, Mr D. Gooding, Department of Agriculture, Western Australia, and Messrs T. B. Alexander and A. F. Ryan, Department of Agriculture, Tasmania.We are indebted to Dr H. de B. Aragão of the Instituto Oswaldo Cruz, Rio de Janeiro, and Dr B. Szyfres, of the Laboratorio de Biologia Animal, Uruguay, for specimens from South America; Dr D. G. McKercher of the University of California School of Veterinary Medicine, Davis, California, for the Californian strains; Drs P. Lépine and H. Jacotot, of the Institut Pasteur, Paris, for strains from France; and Mr J. R. Hudson, of the Veterinary Laboratory, Weybridge, and Dr C. H. Andrewes of the National Institute for Medical Research, Mill Hill, for material from England.We are grateful to Dr S. Fazekas de St Groth and Dr G. S. Watson of this University for advice on the statistical treatment of the data.Mr V. Paral took the photographs.

INFECTION WITH SALMONELLA TYPHIMURIUM IN THE NEWBORN

IN 1939, an outbreak of infection with Salmonella panama was reported in a group of newborn infants in a hospital nursery. 1 The source of the infection was traced to a nurse who had cared for the babies. In agreement with the observations of Schiff, 2 the severity of the disease and the many complications caused by the panama variety of Salmonella pathogens were stressed. Differentiation of Salmonella infection of the newborn from epidemic diarrhea of the newborn was also considered. 3 In addition, attention was called to the variability in symptomatology, clinical course and complications induced by organisms of the Salmonella group. This problem subsequently was discussed further by Seligmann and Hertz. 4 The diversity in the clinical picture of Salmonella infections in the newborn again is shown by the three related outbreaks of infection with Salmonella typhimurium now reported. These outbreaks illustrate the importance of making early diagnostic