Showing papers by "Federal University of Rio de Janeiro published in 1971"

Maturation of convulsogenic activity induced by leptazol in the albino rat

Abstract: 1. Maturation of the excitatory and inhibitory neuromechanisms at various levels of the central nervous system was demonstrated by the convulsogenic activity induced by leptazol in the developing albino rat. 2. The somatomotor end points considered (myoclonic jerk, myoclonic seizure, tonic seizure and catalepsy) were not observed in all age groups. Tonic seizure was seen at birth, myoclonic jerks at 2 weeks of age, myoclonic seizure and catalepsy at 3 weeks of age. 3. The convulsive sequences described presented three different patterns, defining three age groups: the infant pattern (infant group: newborn-1 week old animals); the transitional pattern (transitional group: 2 week old animals); and the adult pattern (adult group: 3 week old-adult animals). 4. Effective doses were determined for the three types of convulsive sequence: MJ50 for the myoclonic major sequence (maximal end point: myoclonic jerk), MS50 for the myoclonic major sequence (maximal end point: myoclonic seizure) and the TS50 for the myoclonic-tonic-clonic sequence (maximal end point: tonic seizure). 5. The correlation of the convulsive patterns with the dose and latency variations suggests that: (a) the neuromechanisms responsible for the tonic seizure and clonic seizure, located at brainstem and spinal cord levels, function at birth and reach maturity at 3 weeks of age; (b) the neuromechanisms responsible for the myoclonic manifestations and for catalepsy, located at the striato-thalamocortical level, start functioning at 2-3 weeks of age, indicating the later maturation of the more cephalic structures.

Geosynclinal evolution of the Epi-Baykalian platform of Central Brazil

Abstract: Evidences of geosynclinal polarity (orogenic and sedimentary) in foldbelts of Central Brazil led the authors to the recognition of seven tectonic isopic zones as parts of a wide geosynclinal system policyclically developed during a long Baykalian Cycle of 1,500-500 m. y. ago. Tectonic and stratigraphic evolutions are reinterpreted on the light of the new concepts.

Upper Quaternary Process Changes of the Middle Amazon Area

Abstract: A chronology for upper Quaternary process changes in the Middle Amazon area is based on the study of the topographic forms and the stratigraphic record, with special attention to the subsurface structure of the slopes. Climatic and eustatic factors seem to have interacted in rather complex ways and sometimes in opposite senses. The upper Quaternary of the Middle Amazon area may be subdivided in at least five phases: (1) Pre-Wisconsin—aggradation by clayey material. (2) Wisconsin—channel degradation related to lowering sea level. Aggradation by mass movement processes in lower order river valleys. Climatic conditions drier than the present ones. (3) Pleistocene post-glacial—aggradation related to the rising sea level and climatic conditions possibly drier than the present ones. (4) Pleistocene Holocene boundary—climatic change toward the present humidity. (5) Holocene—differential aggradation. The rivers rich in suspended load build up their floodplains, while the underloaded autochthonous rivers are subjected to a process of drowning.

Observações sôbre o Triatoma rubrofasciata (De Gerr, 1773) no Estado da Guanabara

Abstract: While capturing triatomidaes in a shanty town on the Morro do Telegrafo (Sao Cristovao - GB) where the dwellings, in their great majority, are made of day or stucco, the authors were able to verify the following: 1) All of the samples captured were of the Triatoma rubrofasciata species. (De Geer, 1.773) . 2) Out of 170 domiciles examined, triatomidaes were found in 23. The smallest sample of triatomidaes per house was one and the maximum was 56. This last number was obtained in two consecutive captures in the same place. 3) Out of 115 samples captured, 8 were nynphs in the first stage, 15 were in the second, 10 in the third, 5 in the fifth, 11 in the sixth, 42 were adult males and 24 females. 4) Not one of the hemiptera examined was infectad by flagellates. 5) A precipitine test made in 17 bugs showed 15 positive results for human, one for rat and one for the pig and chicken blood.

Lista das espécies brasileiras da família sciaenidae owen, 1846 (perciformes, percoidei)

Abstract: A presente contribuicao tem por objetivo apresentar uma relacao dos generos e especies de peixes da familia Sciaenidae, que ocorremno Brasil.

Species differences in the influence of chlorothiazide on curarization.

Abstract: Chez le Chien, le Chat, le Cobaye et le Rat, le chlorothiazide est antagoniste de lad-tubocurarine. Chez le Lapin, le chlorothiazide potentialise la paralysied-tubocurarinique, mais exerce une action antagoniste vis-a-vis d'autres curarimimetiques. L'administration prealable de phenylbutazone transforme en antagonisme la synergie entre le chlorothiazide et lad-tubocurarine.

Panencefalite subaguda esclerosante: transmissão de agente encefalitogênico humano ao macaco rhesus

Abstract: Material proveniente do cerebro de um paciente com "panencefalite subaguda esclerosante" foi inoculado, por via intracerebral, em dois Macacus rhesus. Os animais permaneceram assintomaticos, aparentemente bem, por mais de um ano. Entretanto, 21 e 22 meses apos as inoculacoes comecaram a apresentar sinais de comprometimento neurologico, traduzido por paralisia dos membros posteriores, com apatia e caquexia progressivas. Os animais foram sacrificados. O exame histopatologico do sistema nervoso central mostrou gliose marginal e gliose da substância branca, com os neuronios exibindo sinais de "lesao celular cronica". Foram vistos discretos manguitos inflamatorios perivasculares. Em um animal foi encontrada inclusao acidofila intra- nuclear. Havia tambem proliferacao da glia satelite perineuronal, com satelitose, notadamente no tronco cerebral. No exame das visceras foi encontrado discreto processo de miocardite cronica. Foram retirados fragmentos dos encefalos destes animais e inoculados em 4 outros, tambem por via intracerebral. Estes animais de 2.a passagem apos 2 meses de inoculacao, em media, apresentaram sinais de comprometimento do sistema nervoso central semelhante ao dos animais doadores, de 1a passagem. Houve, portanto, um encurtamento do periodo de inoculacao da molestia. Estes animais tambem foram sacrificados, sendo encontradas gliose marginal, gliose da substância branca, "lesao celular cronica" neuronal e proliferacao da glia satelite, notadamente no tronco cerebral; vasos sanguineos congestos; espongiose cortical. Os animais testemunhas, do mesmo lote, permaneceram normais. Acreditamos que as lesoes observadas nos animais de 1.a passagem, e que se repetiram com maior intensidade e com menor tempo de incubacao nos de 2.a passagem somente podem ser explicadas admitindo-se a existencia de um agente virai que, pela natureza do quadro histopatologico (gliose, "lesao celular cronica" neuronal e espongiose cortical) bem como pelo periodo longo de incubacao, deva pertencer ao grupo dos chamados virus lentos.

Aspectos histopatológicos da encefalite aguda toxoplásmica: (humana e experimental)

Abstract: 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.