Alexandre Alencar

Alterações cerebelares em pacientes com cardiopatia crônica chagásica

Foram estudados 12 cerebelos de pacientes com cardiopatia cronica chagasica, 9 cerebelos de pacientes com cardiopatias nao chagasicas (ambos os grupos constituidos de individuos falecidos em fase de insuficiencia cardiaca congestiva) e dois cerebelos de individuos normais, falecidos acidentalmente. Nos pacientes chagasicos foi verificada reducao numerica nas celulas de Purkinje, alteracoes de natureza regressiva nas celulas remanescentes, alteracoes das cestas peripurkinjeanas e mobilizacao microglial. Estas modificacoes foram tambem encontradas nos cerebelos dos cardiopatas nao chagasicos. As alteracoes observadas foram interpretadas como resultantes da hypoxemia do sistema nervoso central devido a falencia cardiaca.

Demonstracao por imunofluorescencia direta de antigenos do virus da febre amarela em tecido hepatico pre-tratado com tripsina.

A direct immunofluorescence staining technique is described for the detection of yellow fever virus antigen in formalin-fixed liver tissue. Fluorescein-labelled antibody was prepared with batches of immunoglobulin from monkeys immunized with yellow fever strain 17D and show to be free of antibodies to hepatitis A and B viruses. Liver sections were digested with 0.1% trypsin for 2 hours before staining with the fluorescent conjugate. All specimens with hepatocytes showing cytoplasmatic fluorescence were considered positive. In 76 specimens tested there was agreement between histopathology and immunofluorescence in 33 positive and 34 negative cases. Of the remaining 9 specimens with doubtful histopathology, 8 were negative and 1 was positive by immunofluorescence. Specimens from hepatitis of other aetiologies were always negative. Tissue culture cells (VERO) infected with yellow fever virus strain 17D gave strongly positive reactions. The technique described is a useful addition ti histopathology in cases of doubtful diagnosis and makes use of specimens routinely received for diagnosis.

Leucodistrofia metacromática: registro de um caso

A case of metachromatic leucodystrophy in a three years old female patient is reported. Histopathological examination revealed metachromatic inclusions within the cytoplams of the neurons, which led the authors to comment on the physiopathogenesis of this disease, grouping it in cathegory of the lipidoses.A case of metachromatic leucodystrophy in a three years old female patient is reported. Histopathological examination revealed metachromatic inclusions within the cytoplasms of the neurons, which led the authors to comment on the physiopathogenesis of this disease, grouping it in category of the lipidoses.

Aspectos ultra-estruturais da doença de Parkinson

Brains from four parkinsonian patients and one control patient were analysed by electron microscopy. The most consistent abnormal findings were nerve fibers rarefaction, great interstitial space enlargement, neuropil disruption, mitochondrial tumefaction and degenerative changes. These findings occurred regularly in the brain of parkinsonian patients. Furthermore, except for mitochondrial changes, they were distinctively absent in the control patient, and therefore cannot be attributed to technical problems. Contrary-wise, they clearly reflect chronic neuronal loss. Also noteworthy was the demonstrative of deposits of amorphous substance into mitochondria, axons, cytoplasm and into the interstitial space.

Panencefalite subaguda esclerosante: correlação entre aspectos imunológicos e histopatológicos

The Authors relate a clinical, laboratorial, eletroencephalografic and virological study of four patients with the clinical diagnosis of subacute sclerosing panencephalitis (SSPE). All four had high levels of anti-measles antibodies in the cerebrospinal fluid and in the blood, and in three of them the levls were higher in the cerebrospinal fluid. Cerebral biopsies were performed on two of these patients, showing a picture of chronic meningoencephalitis, with scattered foci of neurophagia and perivascular inflammatory infiltrates of lymphocytes and plasma cells. The Authors also review eighteen previously published cases, in order to analyse more fully the nature of the perivascular and meningeal inflammatory infiltratos. The histopathologic is of slight meningeal inflammatory reaction, which contrasts with the dense perivascular infiltrates of lymphocytes and plasma cells, which frequently present a great number of Russell bodies. In view of these findings, the Authors suggest that the anti-measles antibodies, which were found in such high concentrations in the cerebrospinal fluid, might be produced in the perivascular inflammatory infiltrates within the central nervous system.

Panencefalite subaguda esclerosante: participação da oligodendróglia no processo desmielinizante

It was made a clinical-pathological study of six (6) cases of subacute sclerosing panencephalitis (SSPE) in order to demonstrate that the demyelinating process observed in this disease has its origin in the destruction of oligodendroglial cells by viral parasitism. As we know oligodendroglial cells are responsible for the myelination in the Central Nervous System. It was made a brief historical revision of the oligodendroglial cells concept and, after the description of the six cases, we tried to demonstrate that the demyelinating process observed are the result of oligodendroglial cells destruction.

Implantação intracerebral experimental de sarcomas

Histopathological study of intracerebral implantation of sarcomas, performed in rats (fibrosarcomas) and mice (sarcoma 180). The intracerebral implantation of fibrosarcoma has developed in about 45 days a well limited tumor, with little infiltration of the adjacent nervous parenchyma, never streading to longer distances because the strong cohesion between its cells, with great differentiation of reticular fibers and collagen. On the contrary, the innoculation of sarcoma 180, chiefly of the ascitical form, has rapidly lead to a strong intracranial hipertension, with dissemination of neoplastic cells through the subarachnoid and intraventricular spaces. Both neoplasies were extending through the perivascular spaces, but in different ways: the sarcoma 180 had a very strong and rapid dissemination to long distances, while the fibrosarcoma disseminated only to the vessels adjacent develloping tumor. Based on personal observations and on specialized bibliography, we concluded that the etiological agents of these tumors exerts their action on different cellular strains.

Histopathologic aspects of toxoplasmic acute encephalitis (human and experimental)

A histopathologic study of two cases of acute human toxoplasmic encephalitis are reported, showing: a) the distribution of the inflamatory infiltrates, clearly in connection with the vascular network; b) the cellular constitution of the inflamatory infiltrates and peri-vascular cuffs and their histogenesis. The results are considered and compared with experimental material from rabbits.

Alterações nucleares e nucleolares nas panencefalites subagudas esclerosantes

A study of nuclear and nucleolar alterations found in cases of subacute sclerosing leucoencephalitis of van Bogaert (three cases) and of Dawson type (four cases) and in nodular panencephalitis of Pette-Doring (three cases) is reported. In all these types of encephalites there was found anisonucleolinosis with extrusion of nucleolinus, alterations not yet reported in these precesses. These nucleolar changes were found more frequently in Pette-Doring than in Dawson and Van Bogaert types, being a strong argument favouring the viral aetiology of these diseases.

Análise ultra-estrutural do líquido cefalorraquiano de parkinsonianos

Ultrastructural cerebrospinal fluid of 20 parkinsonian patients examined by negative staining shewed not recognizable strutures thought to be of viral origin in 6 cases (30%). However, mortality rate analysis failed to disclose significant differences between the inoculated animals. Either artefact or not, such structures deserve to be reported.Ultrastructural cerebrospinal fluid of 20 parkinsonian patients examined by negative staining showed not recognizable structures thought to be of viral origin in 6 cases (30%). However, mortality rate analysis failed to disclose significant differences between the inoculated animals. Either artefact or not, such structures deserve to be reported.