Showing papers by "Oswaldo Cruz Foundation published in 1980"
TL;DR: The many obscure aspects and challenging problems explain the increasing use of T. cruzi as a model for the study of humoral and cellular immunity in both basic and applied immunology.
Abstract: Publisher Summary Trypanosoma cruzi (T. cruzi), the causative agent of Chagas disease, is a digenetic trypanosomatid, which circulates in the bloodstream of the vertebrate host as trypomastigotes and has an obligatory intracellular phase in which the parasite multiplies as amastigotes, which differentiate into trypomastigotes. From an immunological point of view, therefore, the parasite presents stages that are directly exposed to the effector elements of the immune response, such as antibodies and macrophages, as well as stages that are sequestrated within host cells. T. cruzi infection is characterized by an acute phase with large numbers of parasites and by a sub-patent chronic phase in which circulating and tissue stages are difficult to detect. The mechanisms involved in the resistance to the parasite and in the control of parasitism during the chronic phase are not known. Chagas disease is life-long and spontaneous cures do not occur. There is increasing evidence that auto-immune processes participate in the pathogenesis of the cardiac and digestive forms of the disease. These many obscure aspects and challenging problems explain the increasing use of T. cruzi as a model for the study of humoral and cellular immunity in both basic and applied immunology.
197 citations
TL;DR: The preliminary results of the parasitological examination of some coprolites collected by the staff of the Instituto de Arqueologia Brasileira, Rio de Janeiro are reported.
Abstract: Introduction The study of parasites in human coprolites can throw light on such questions as the origin and antiquity of parasitic associations in different parts of the world, thus increasing our knowledge of the history of parasitic diseases, and can also be used as an aid to the interpretation of habits and migrations of prehistoric populations. Earlier work on these lines includes that of Przzr & SCHENONE (1954), WITENBERG (1961), PIKE (1968), FRY & HALL (1969), MOORE et al. (1969) and FONSECA (1970), among others. We here report the preliminary results of the parasitological examination of some coprolites collected by the staff of the Instituto de Arqueologia Brasileira, Rio de Janeiro.
68 citations
TL;DR: Culture forms of 104 stocks of Trypanosoma cruzi isolated in different regions of the State of Bahia were compared by electrophoresis of six enzymes, finding that both T. cruzi Z1 and Z2 appeared to be pathogenic in man and both were associated with endemic Chagas's disease.
Abstract: Culture forms of 104 stocks of Trypanosoma cruzi isolated in different regions of the State of Bahia were compared by electrophoresis of six enzymes. The three distinct combinations of isoenzyme patterns seen were designated ZI, Z2 and Z3. In an area of endemic Chagas's disease in eastern Bahia, T. cruzi Z1 was associated with sylvatic mammals and sylvatic triatomines, whereas T. cruzi Z2 was associated with a separate domestic cycleof transmission. T. cruzi Z1 was also found in sylvatic triatomines from other parts of the State. In contrast, in an area of the Sao Francisco Valley region of western Bahia, both T. cruzi Z1 and Z2 were isolated from man, domestic animals, and peridomestic rats. T. cruzi Z3 was isolated from an armadillo and from Panstrongylus geniculatus, a triatomine commonly found in armadillo burrows. Both T. cruzi Z1 and Z2 appeared to be pathogenic in man: T. cruzi Z1 was isolated from patients with acute Chagas's disease and from a single patient with chronic cardiac manifestations. T. cruzi Z2 was isolated from some asymptomatic individuals but was also associated with acute disease and chronic cardiac and digestive syndromes.
65 citations
TL;DR: Mice inoculated with trypanosoma cruzi display an intense thrombocytopenia which is more severe in animals infected with the Y than CL strain and is likely to be related to more general phenomena affecting the host rather than to direct damage of platelets or precursor cells by parasitism.
Abstract: Mice inoculated with trypanosoma cruzi display an intense thrombocytopenia which is more severe in animals infected with the Y than CL strain. In animals inoculated with a T. cruzi strain which induces chronic infection (Colombiana), the number of platelets decreases as parasitemia ascends, and then reverts to normal values as soon as the acute infection merges into the chronic phase. The mechanisms involved in the thrombocytopenia are still obscure and are likely to be related to more general phenomena affecting the host rather than to direct damage of platelets or precursor cells by parasitism. Anemia and leukopenia are also present in T. cruzi infected mice.
48 citations
TL;DR: The characteristics of protein synthesis in cells infected with these virions are similar to those in uninfected cells, thus revealing analogous defects in the genome of the majority of defective virions.
Abstract: The ability of Mycobacterium leprae to specifically bind α2-laminins of Schwann cells has been described recently as being an important property of the leprosy bacillus, which could explain the neural tropism of M. leprae. Therefore, the extent of the expression of α2-laminin-binding properties among mycobacteria was investigated. In an ELISA-based assay, all three species of Mycobacterium tested (M. tuberculosis, M. chelonae and M. smegmatis) expressed laminin-binding capacity, suggesting that the ability to bind α2-laminins is conserved within the genus Mycobacterium. This report also demonstrated that not only M. leprae but all the mycobacterial species tested readily interacted with the ST88-14 cells, a human schwannoma cell line, and that the addition of soluble α2-laminins significantly increased their adherence to these cells. These results failed to demonstrate the presence in M. leprae of a unique system based on α2-laminins for adherence to Schwann cells.
42 citations
TL;DR: Serological examination for Toxoplasma gondii in human blood samples and in blood samples from ten different species of animals obtained in Manaus, State of Amazonas-Brazil, are compared with results obtained from similar examinations of blood from humans living in other areas of the Amazon basin.
Abstract: Serological examination for Toxoplasma gondii in human blood samples and in blood samples from ten different species of animals obtained in Manaus, State of Amazonas-Brazil, are compared with results obtained from similar examinations of blood from humans living in other areas of the Amazon basin. The domestic cat (Felis catus) showed the highest levels of antibody for Toxoplasma gondii, whereas the domestic chicken (Gallus domesticus) and duck (Cairina sp) the lowest. The other animals showed similar intermediate levels of antibody to this protozoa. The authors discuss the results and several aspects of the involvement in epidemiology of toxoplasmosis and call attention to some transmission mechanisms not yet elucidated.
33 citations
TL;DR: The phagocytosis activity of the macrophages was recovered within 6–8 hr after the removal of Pronase, and described membrane components may help to explain the tropism of some T. cruzi strains for cells of the mononuclearphagocytic system in the living host.
25 citations
TL;DR: The high frequency of reactions suggests either cutaneous reactivity to T.infestans without prior sensitization or cross reactivity between P. megistus and T. infestans.
Abstract: We determined the frequency of cutaneous allergic reactions to bites of Triatoma infestans during xenodiagnosis in a rural community where Panstrongylus megistrus is the only domestic vector of Trypanosoma cruzi. Localized urticaria or more intense cutaneous allergic reactions at 48 and 72 hours were observed in 86.7% and 82.1% respectively of the individuals in our study. Urticaria was more severe in children and older adults and in women than in men. The high frequency of reactions suggests either cutaneous reactivity to T. infestans without prior sensitization or cross reactivity between P. megistus and T. infestans. A single application of topical corticosteroid or antihistamine medication did not reduce the cutaneous reactions.
21 citations
TL;DR: This species of bug was reared with difficulty in the laboratoty and required about 350 days to develop from egg to adult.
Abstract: Triatoma melanocephala Neiva & Pinto, 1923, a rare species of triatomine with a restricted geographic distribution, is redescribed in the presente paper. Specimens of adults were collected inside houses and adults and nymphs naturally infected with T. cruzi were found in bromeliad epiphyts in sylvatic sites. This species of bug was reared with difficulty in the laboratoty and required about 350 days to develop from egg to adult.
17 citations
TL;DR: The Schistosomiasis mansoni was taken as an example because of its medical and public health significance in the nosologic picture of Northeast Brazil and an analysis of the immunologic response in the pathobiology of nutrition / infection interrelationships was made, with special reference to the negative role of protein and iron deficiencies on cellular immunity.
Abstract: The use of the theory of the general systems for studying the parasitic diseases has led to a better comprehension of the host parasite relationships and of the varying differences found in morbidity and biology of the parasitic diseases. Since environment has been considered an ecosystem of the individual, it can act upon man either by a direct action of the parasite on the host or as a determinant of food deficiencies. Among the consequences of the direct action of the infectious agent on the nutritional status of the host we can observe generalized catabolic disturbances. Also, secondary malabsorption syndromes and haematological alterations like aneamias of several types can be developed in the host's body by different mechanisms. The effects of undernutrition on the biology of the parasites are still better understood and, in the present paper, the Schistosomiasis mansoni was taken as an example because of its medical and public health significance in the nosologic picture of Northeast Brazil. Mice were fed with semi-purified and "natural" diets (similar to those consumed by the population living in endemic areas of Northeast Brazil where important endemic foci of this parasite are found). Finally, an analysis of the immunologic response in the pathobiology of nutrition /infection interrelationships was made, with special reference to the negative role of protein and iron deficiencies on cellular immunity.
11 citations
01 Dec 1980
TL;DR: In this paper, a morfologia do polen of cerca 35 especies, examinando-se 182 exemplares, do genero Kielmeyera, was studied, and a definicao polinica for cada especie nao foi possivel ser obtida.
Abstract: RESUMO Foi estudada a morfologia do polen de cerca 35 especies, examinando-se 182 exemplares, do genero Kielmeyera, a fim de poder limitar as especies ou grupos delas; este estudo baseou-se no nome, e respectivo numero de coleta, dos coletores, possibilitando desta maneira definir polinicamente as exsicatas examinadas. Foram estabelecidos dois grandes grupos de especies: o primeiro compreende aquelas cujos graos de polen ocorrem em monades, ou seja com graos isolados; o segundo, com a maioria das especies, compreende aquelas cujos graos se apresentam reunidos em grupos,formando tetrades, ditetrades ou poliades, podendo-se encontrar estas tres possibilidades num mesmo exemplar. Por sua vez, estes dois grandes grupos foram divididos em subgrupos, baseando-se na estrutura das exinas nas regioes subequatoriais dos graos de polen. Assim, o polen das Kielmeyeras ficou pertencendo a 5 tipos polinicos que incluem 14 subtipos. Uma definicao polinica especifica para cada especie nao foi possivel ser obtida. Com a aplicacao adicional dos dados obtidos ao nivel da ultra-estrutura das exinas puderam ser feitas consideracoes quanto a relacoes filogeneticas das especies e exsicatas examinadas. Relacionando-se as especies com as formacoes ecologicas nas quais ocorrem, foi verificado que aquelas com poliades de superficies lisas, insuladas ou verrugosas ocorrem em ambientes ecologicos mais secos: campos, cerrados e cerradao, enquanto que as com poliades de superficies microreticuladas e reticuladas, bem como as com monades, tem preferencia por ambientes mais umidos, as florestas e tambem as restingas.
TL;DR: The authors confirmed in laboratory conditions the occurrence of burrowing in the behavioral repertoire of Biomphalaria glabrata and observed that the burried snails recovered, after a 20 days' desiccation period, better than others that had remained on the soil surface.
Abstract: The authors confirmed in laboratory conditions the occurrence of burrowing in the behavioral repertoire of Biomphalaria glabrata. They observed that the burried snails recovered, after a 20 days' desiccation period, better than others that had remained on the soil surface. More detailed work is necessary to determine the epidemiological importance of such behavior.
Journal Article•
TL;DR: The adult, pupal and larval morphology of S. argentiscutum sp.
Abstract: The adult, pupal and larval morphology of S. argentiscutum sp. nov., a member of the S. amazonicum-group, is compared with S. amazonicum Goeldi and its distribution, biology and medical importance are discussed. S. argentiscutum is one the most important anthropophilic species in the S. amazonicum-group as it is responsible, together with S. amazonicum, for the transmission of Mansonella ozzardi in Brazil.
TL;DR: The results suggest that the sound stimulation has a destructible effect upon the parenchima cells of the pineal gland of the female albino rats.
Abstract: The authors studied the effect of noise (110 dB), delivered by an eletric bell, upon parenchima cells of pineal gland of albino female rats. Several experimental groups were previously formed and stimulated during, 1, 2, 4 and 7 days. In addition another group was formed and stimulated during 7 days plus 10 additional stimulations of about 3 minutes each after the routine stimulations in the seventh day. The authors observed that a single stimulation of about 3 minutes was sufficient to determine alterations in the parenchima cells of the pineal of experimental animals; the changes were characterized by picnolisis in some groups, whereas in others groups picnolisis and interstitials vacuolizations were evidently increased directly with stimulation. The results suggest that the sound stimulation has a destructible effect upon the parenchima cells of the pineal gland of the female albino rats.
TL;DR: Foram discutidos aspectos relacionados a suscetibilidade de B. straminea e a importância dos resultados obtidos.
Abstract: A suscetibilidade de exemplares de B. straminea descendentes de uma amostra originaria do municipio de Piripiri (Piaui, Brasil), foi testada face a duas cepas de Schistosoma mansoni: "LE" (Belo Horizonte) e "SJ" (Sao Jose dos Campos). Verificou-se que a cepa "SJ" infectou 12,5 (8) dos exemplares sobreviventes de B. straminea e 63,6% (14) de B. glabrata usadas como controle. Quando exposta a cepa "LE" do trematodeo, B. straminea mostrou-se refrataria, enquanto 84,0% (42) dos exemplares de B. glabrata utilizadas como controle encontravam-se positivas para o S. mansoni. Foram discutidos aspectos relacionados a suscetibilidade de B. straminea e a importância dos resultados obtidos.
Journal Article•
TL;DR: The taxonomic position and relationships of Culicoides (Hoffmania) saintjusti, (Oecacta) macieli sp.
Abstract: Culicoides (Hoffmania) saintjusti sp. n. and (Oecacta) macieli sp. n. (Type-locality: Brazil, Rio de Janeiro, Jacarepagua, Pau da Fome) are described and its taxonomic position and relationships with others subgeneric species are discussed.
TL;DR: Foi realizado estudo transversal sobre a esquistossomose mansonica em nove engenhos da usina Catende localizada na Zona da Mata sul do Estado de Pernambuco (Brasil).
Abstract: Foi realizado estudo transversal sobre a esquistossomose mansonica em nove engenhos da usina Catende localizada na Zona da Mata sul do Estado de Pernambuco (Brasil). A prevalencia foi 43,8% para a populacao geral dos engenhos e 64,6% para os trabalhadores de campo. A prevalencia das formas hepato-esplenicas foi 4,1% sendo que em dois engenhos chegou a 8,7% e 9,1%. Biomphalaria straminea foi o unico molusco transmissor encontrado na area; sua taxa de infeccao natural por S. Mansoni foi 0,07%. A esquistossomose pode ser considerada como doenca grave na regiao estudada.
TL;DR: A cell fractionation procedure previously developed for Trypanosoma cruzi was applied to isolated the plasma membrane of promastigotes of Leishania mexicana amazonensis and showed that this fraction is able to induce cell-mediated immune response in mice.
Abstract: A cell fractionation procedure previously developed for Trypanosoma cruzi was applied to isolated the plasma membrane of promastigotes of Leishania mexicana amazonensis. The cell, swollen in an hypotonic mediun, were disrupted in the presence of a nonionic detergent and the membrane fraction isolated by differencial centrifugation. Electron microscopy showed that the fraction consisted of pieces of the plasma membrane associated with subpellicular microtubules. It was also shown that this fraction is able to induce cell-mediated immune response in mice.
TL;DR: Adults and larva of Simulium spinibranchium Lutz, 1910 are described for the first time and the pupa is redescribed.
Abstract: Adults and larva of Simulium spinibranchium Lutz, 1910 are described for the first time and the pupa is redescribed. A lectotype is estabilished for the species. The Geographical Distribuition and some Biologic data are presented.
Journal Article•
Journal Article•
TL;DR: In this paper, a clinical, laboratorial, eletroencephalografic and virological study of four patients with the clinical diagnosis of subacute sclerosing panencephalitis (SSPE) was conducted.
Abstract: 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.
TL;DR: The complement fixation reaction and indirect immunofluorescence were used to test serum from 3,000 potential blood donors at the Blood Bank of the University Hospital, Londrina, Parano State, Brazil and showed the relative nature of the process of donor selection on the basis of serological reactions.
Abstract: The complement fixation reaction (CF) and indirect immunofluorescence (IF) were used to test serum from 3,000 potential blood donors at the Blood Bank of the University Hospital, Londrina, Parano State, Brazil. A total of 7.4% of positive serological reactions was the results of the two tests being concordant in 97.1% and discordant in 2.9%. The IF test was more sensitive than CF; positive results by IF with negative or doubtful results by CF were 15 times more frequent than positive results by CF with negative or doubtful results by IF. Judging by the results of the two tests, the security of selection of acceptable blood samples was greater when doubtful results or anti complementary sera were considered positive. In another group of volunteer candidates for blood donation who had donated blood on other occasions, 450 had had one to six CF tests carried out in other laboratory. Of these, 10 (2.2%) had had doubtful or positive reactions in one or more of these previous tests but had been accepted as potential donors at the time of the present study. These results demonstra te the relative nature of the process of donor selection on the basis of serological reactions. The alternative utilization of gencian violet by hemotherapy services is discussed.
TL;DR: This method was shown to be efficient for concentrating enterovirus in sewage water, allowing its detection in samples containing about 1 infectious unit per m1, and without a previous concentration, the isolation of virus from such diluted samples was not possible.
Abstract: The efficiency of a method which uses A1 (OH)3 for concentrating enterovirus in sewage water was tested in an experimental study. Gel of aluminium hidroxide (in a proportion of 1g per 3,78 1) was added to the previously clarified sewage water with the pH adjusted to 5,0. After shaking for 1 hour, the mixture was filtered through a Millipore membrane type AP-20. The A1 (OH)3 with the adsorbed virus retained on the membrane was removed by means of a spatula. Eagles's medium with 10% foetal calf serum was used for elution and the pH was adjusted to about 7,2-7,4. The mixture was then centrifuged at 20.000 x g, the pellet discarded and the supernatant was inoculated into cells of the strain LLC-MK2 for viral quantification. In a parallel experiment, samples of crude sewage, that is, without previous concentration treatment, were inoculated into cells. This method was shown to be efficient for concentrating enterovirus in sewage water, allowing its detection in samples containing about 1 infectious unit per m1. Without a previous concentration, the isolation of virus from such diluted samples was not possible.
TL;DR: This technique has allowed accurate measurements of different aspects of the activity of Biomphalaria glabrata, and can be useful in analysing the level of response of planorbids to molluscicides, in experimental tests, as well as their protective behavior under general adverse conditions.
Abstract: A technique involving time-lapse cinematography was developed for studying the behavioral repertoire of planorbids in laboratory conditions. Observations were carried out within a chamber with controlled light and temperature; recording was done by single frame shooting at 10 second intervals, with synchronized strobed flash. This technique has allowed accurate measurements of different aspects of the activity of Biomphalaria glabrata (Say, 1818), and can be useful in analysing the level of response of planorbids to molluscicides, in experimental tests, as well as their protective behavior under general adverse conditions.
TL;DR: For the first time it has been detectedLutzomyia longipalpis at Praia Vermelha, a beach of an offshore island of the Rio de Janeiro State (Ilha Grande), Brazil and attention must be paid to its possible epidemiological importance.
Abstract: For the first time it has been detectedLutzomyia longipalpis at Praia Vermelha, a beach of an offshore island of the Rio de Janeiro State (Ilha Grande), Brazil and attention must be paid to its possible epidemiological importance.