Publications by authors named "Heath R"

Electron microscopic study of brain tissues of monkeys chronically exposed to psychoactive Cannabis showed widening of the synaptic cleft, electron opaque material in the cleft and in pre- and postsynaptic regions, and some "clumping" of synaptic vesicles. In contrast, tissues of control monkeys showed no ultrastructural changes.

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The development of a cell-mediated immune response to Sendai virus infection in mice was examined by the use of a 51Cr release assay of cytotoxicity. A low level of "background cytotoxicity" to Sendai virus-infected L cells was found in the spleens of uninfected CBA mice. Spleen cells from Sendai-infected mice showed an elevated level of cytotoxicity against these target cells for a period of 5 weeks, commencing 4 days after infection of the mice.

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Against the background previous findings in epileptic patients, in whom electroencephalographic recordings were obtained from numerous deep and surface brain sites during seizures, rhesus monkeys with electrodes implanted into specific brain sites were used to demonstrate anatomical connections by evoked potential techniques and to serve as models of experimental epilepsy. In the animals, many monosynaptic connections were revealed between forebrain sites consistently involved in seizures in patients and more caudal brain sites subserving functions of sensory perception, eye movement, synaptic chemical transmission, and motor coordination. Further, the participation of these interrelated sites during seizures was demonstrated.

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Two passive haemagglutination methods for detecting HBsAg were compared. In general, the method using turkey erythrocytes was found preferable to the method employing sheep cells since it is more rapid and more sensitive, and less frequently gave rise to false positive reactions with sera from staff, blood donors, and patients not receiving haemodialysis. The turkey cell test gives rise to more false positive screen tests than the sheep cell test when monitoring renal dialysis patients since approximately 10% of the sera of these patients were found to contain turkey cell agglutinins, but this presents no particular difficulty if the recommended absorption procedures are used.

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Identification of brain sites where physiologic activity was correlated with subjective emotional experiences in patients undergoing treatment was the starting point for our investigations of the neural basis for emotion and related clinically documented behavioral phenomena. By use of anatomic and physiologic techniques, the neural substrate has been shown to be notably different from that which continues to be described in textbooks, that is, the limbic system. Establishing the neurophysiologic basis for emotion has led to effective treatment for some neurologic and psychiatric disorders.

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Experience with a 9-year-old girl with Dysplasia Epiphysealis Hemimelica in the right lower extremity demonstrates that avoidance of confusion leading to medical--legal problems and promotion of effective management would have been possible by early recognition of the condition.

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Sucrose density gradient ultracentrifugation can be used to detect specific 19S antibodies of the IgM class in the sera of patients recently infected with influenza A virus, provided steps are taken to remove non-specific inhibitors of haemagglutination. The usefulness of the procedure for the diagnosis of influenza requires further evaluation.

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Organochlorine residues in wings of adult mallards and black ducks were monitored during the 1972-73 hunting season. DDE, DDT, DDD, dieldrin, and polychlorinated biphenyls (PCB's) were present in all samples. Mallard wings from Alabama contained the highest mean levels of DDE, DDT, DDD, dieldrin, and PCB's.

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The unicellular algae Chlorella sorokiniana was used as a model system to investigate the interaction of ozone with plant cell membranes. Ozone induces K(+) leakage from Chlorella sorokiniana similar to the electrolytic loss observed from many higher plants under stressful conditions. The kinetics of this leakage indicate that ozone initially interacts reversibly (within sec) with sites on membranes allowing a passive efflux of K(+).

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Nearly three and a half thousand sera obtained from various populations were tested serologically to obtain evidence of past infection with influenza A viruses that were prevalent from 1947 to 1972. No significant difference was found between the distributions of the levels of these antibodies of individuals of blood groups A and O, A1 and O, Rh (D+) and Rh (D-) and MM, MN and NN. The significance of these findings is discussed.

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This paper describes the assembly (from commercially available components) of an antilog converter, which transforms the output signals of ion-specific electrodes to ionic concentrations suitable for a linear recorder. It responds linearly to cation concentrations from 10 mum to at least 10 mm and can be used for electrodes kept at any temperatures (0 to 50 C). The leakage of K(+) from a unicellular algae (Chlorella sorokiniana) can be induced by Triton X-100, heating, or suspension in a tris buffer and is used to demonstrate the operation of this device.

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Near-ultraviolet irradiation of actively growing yeast cells leads to cell death by two distinct mechanisms. The first type of cell death is evident after low doses of near-ultraviolet light (3 times 10-4 ergs times mm- minus 2) and is due to a reversible inactivation of the respiratory capacity of the cell. In studies with yeast mitochondrial membranes the quinones were identified as the site of inactivation by determining the relative levels of the following oxidase activities after irradiation: exogenous NADH, endogenous NADH (via isocitrate dehydrogenase), succinate, and D-lactate oxidases.

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Induced immunosuppression with the drug cyclophosphamide was shown to convert the relatively harmless infection with an avirulent strain of Kunz influenza virus into a fatal pneumonic illness. The drug was also shown to increase the mortality of mice infected with low concentrations of a virulent variant of this strain, but it delayed the time of death of mice that were infected with high concentrations ofthe same variant. The probable roles of immune and inflammatory mechanisms in recovery from primary influenza virus infections are discussed.

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Carbonic anhydrase activity was determined in spinach (Spinacia oleracea) leaf organelles isolated on sucrose density gradients and was found to be predominantly in the intact chloroplast fraction. The small amount of activity associated with the mitochondrial fractions was probably due to intact chloroplast contamination. No activity could be associated with the broken chloroplast or microbody fractions.

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For the past 25 years, the research program of the Tulane University Department of Psychiatry and Neurology has been directed primarily to the development of treatment for patients with certain psychiatric and neurological disorders that have been resistant to commonly used therapy. In the course of investigations, using a variety of approaches, new techniques have evolved which have permitted simultaneous exploration of brain activity and behavior. The data reported substantiate an anatomical localization in the brain for the syndrome of psychotic behavior.

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