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M T Gil

Publications and source records attributed to M T Gil.

23 records · Page 2Linked to original sources
PubMed1978

How do normal subjects learn a simple adaptative task: how and why do paranoid schizophrenic patients fail?

The authors studied the behavior of normal subjects and paranoid schizophrenic patients in a simple problem-solving situation. The schizophrenics were divided into two sample groups, one of individuals under treatment and the other of individuals not under treatment. The learning process involved in this problem-solving situation is very similar to an instrumental conditioning, and can be understood by means of the following assumptions: (1) the subjects use decision functions in reacting to the stimuli, although they may be not fully aware of this; (2) learning is the result of successive transformations of these decisions in the course of time; (3) the changes have specific probabilities and are related to (a) those responses which are made to the latest stimuli, and (b) a differential probability for decision functions which were effective, or only interrupted painful reinforcement, or were completely ineffective. In schizophrenics further factors of importance were (1) an 'inertia' factor and (2) the rigidly continued use of unsuccessfuly or only partially successful decision criteria. The authors used a systems theory based on Galois field theory and a calculus of operators specifying three groups of subjects. A computer program based on thses hypotheses was tested in a stimulation experiment. The statistical evaluation of the results showed a congruence between the theoretical approach and the experimental data.

Cognition↗
PubMedDate not supplied

[Late hepatitis C virus seroconversion in a patient on hemodialysis].

We present a case of an exceptionally late HCV seroconversion in a hemodialysis patient. The clinical case illustrates the difficulty of appropriately and quickly isolating a HCV infected patient, and it demonstrates the necessity to consider all the dialysis patients as potentially infectious patients. The standard precautions in hemodialysis must be applied routinely to all the patients, because the diagnosis of the HCV infection is very often late, and on some occasions it is difficult to interpret correctly the results of the available diagnostic tests.

Adult↗
PubMedDate not supplied

[Nosocomial transmission of the hepatitis C virus in hemodialysis: monitors, personnel, or both?].

BACKGROUND: The Hepatitis C virus (HCV) infection is the most frequent cause of hepatic disease in the dialysis population. Many observations suggest that nosocomial transmission is the principal way of infection. OBJECTIVE: The aim of this study was to investigate HCV outbreak in a hemodialysis (HD) unit, using epidemiological and molecular methods. METHODS: 50 patients in a HD unit were tested for HCV-RNA by reverse transcription-polymerase chain reaction (PCR), and the hepatitis C genotype determination (reverse hybridization assay). We analyzed the distribution of different genotypes by shifts and dialysis machines and the temporal association in the appearance of the HCV cases. RESULTS: 21 of 50 patients (42%) showed detectable anti-HCV antibodies (HCV-Ab) in serum. The prevalence of HCV RNA positivity was 90.4% (19/21) among these patients. None of the HCV-Ab negative patients detectable HCV virus in thein blood. The PCR genotyping of HCV RNA was performed in 19 patients. It detected the presence of HCV subtype 1b in 10 out of 19 viremic patients (52.6%), HCV-subtype I a in 31.5% of the patients (6/19) and genotype 3 in 15.7% (3/19) of the viremic patients. All patients had been infected by only one genotype. We found epidemiological correlation and temporal association between the genotypes 1b (p < 0.05) and 3 (p < 0.05) with the shifts. The HCV genotype 1a shows statistical association with the machine 1 (p < 0.05) but not temporal association. CONCLUSIONS: HCV genotype 1b was dominant in our cohort of HCV-infected patients. There was a high level of agreement between the PCR detection of HCV RNA and the detection of antibodies against the HCV genome. Genotyping and epidemiological analysis suggest that horizontal nosocomial patient to patient transmission plays an important role in the epidemiology of HCV in dialysis patients. There is a need for stringent implementation and regular auditi of infection control measures.

Cross Infection↗
PubMedDate not supplied

[Interhemispherical study of the activities of aminopeptidases, lactate dehydrogenase and glutamate-oxaloacetate transaminase in the rat brain].

Aminopeptidase activity has been assayed from both soluble and membrane bound fractions in eleven regions of the left and right hemispheres of the rat brain, using L-leucine-2-naphthylamide as substrate. Two other metabolic enzymes, lactate dehydrogenase and glutamate-oxalacetate aminotransferase activities were simultaneously determined in the same areas. When individual zones of the left hemisphere were compared with its corresponding right zones, soluble aminopeptidase activities were significantly higher in left frontal cortex and left hypothalamus than in right frontal cortex and right hypothalamus, respectively. No other significant differences were found neither in the remaining areas nor for the other enzymatic activities between both brain hemispheres.

Aminopeptidases↗