Showing papers by "Oswaldo Cruz Foundation published in 1989"
TL;DR: The data summarized in this paper on parasite taxonomy and geographic distribution come from studies of greater than 1,000 New World Leishmania isolates identified by species-specific monoclonal antibodies using an indirect radioimmune binding assay and from scientific literature.
Abstract: A review of the epidemiologic aspects of the New World leishmaniases, including their known geographic distribution, etiologic agents, zoonotic reservoirs, and insect vectors, based on biological and molecular characterization of Leishmania isolates is presented. Data summarized in this paper on parasite taxonomy and geographic distribution come from our studies of greater than 1,000 New World Leishmania isolates identified by species-specific monoclonal antibodies using an indirect radioimmune binding assay and from scientific literature.
506 citations
TL;DR: This method should prove useful as a rapid, specific and sensitive assay for Chagas' disease in chronic patients as well as for epidemiological studies of infected animals and insects.
296 citations
TL;DR: An anopheline survey in four localities in Rondônia, the most malarious State in the Brazilian Amazon, An.
Abstract: In view of recent studies incriminating several species of anophelines, besides Anopheles darlingi, as malaria vectors in the Brazilian Amazon, we performed an anopheline survey in four localities - Ariquemes, Cujubim, Machadinho and Itapoa do Oeste - in Rondonia, the most malarious State in the Country. Twenty species were found. An. darlingi was, by far, the dominant species and the only one whose density coincided with that of malaria. On human baits it was more numerous in the immediate vincinity of houses than indoors whre, however, it was almost the only species encountered. On both situations it fed mostly at sunset and during the first half of the night. It was less numerous far from houses and scarce inside the forest. Other species (An. triannulatus, An. evansae, An. albitarsis, An. strodei) appeared in appreciable numbers only in Ariquemes, both in areas with and without malaria. The remaining species were scanty. An. darlingi was confirmed as the primary local vector.
115 citations
TL;DR: Trypanosoma cruzi genes were cloned in lambda gt11 and screened with an anti-trypomastigote antiserum, selecting two out of twelve clones in view of their reactivity with human chagasic sera.
90 citations
TL;DR: There is evidence suggesting that leishmaniasis is a zoonosis, possibly with equines and dogs as reservoirs, although both a wild enzootic cycle and the role of man as a source of infection can not be ruled out.
Abstract: After outbreaks of cutaneous leishmaniasis in Solano State, Venezuela, 5% of the population had parasitized ulcers while after similar outbreaks in Mesquita, Rio de Janeiro State, Brazil, 9% had the disease. In these foci children, including some under six years of age, wre affected. There was no significant difference in the occurence of the disease according to sex or type of employment. In Solano, 3% of dogs and 28% of donkeys had parasitized lesions, while in Mesquita these indices were 19.8% and 30.8% respectively. The parasite from man, dogs and equines was identified as Leishmania (Viannia) braziliensis, by zymodeme and serodeme characterization. In these foci there is evidence suggesting that leishmaniasis is a zoonosis, possibly with equine and dogs as reservoirs, although both a wild enzootic cycle and the role of man as a source of infection can not be ruled out. Transmission is assumed to occur peridomestically by sandfly vectors such as Lutzomyia panamensis in Venezuela and Lutzomyia intermedia in Brazil. Information about the origin of these foci suggests that infected equines may be an important factor in the dissemination of the parasite in a peridomestic situation where these sandflies are abundant.
76 citations
TL;DR: It is concluded that placental morphology needs to be substantiated by special laboratory techniques for the detection of cytomegalovirus infection.
72 citations
TL;DR: The results suggest that the immune response of humans to paramyosin may play a role in natural resistance to schistosome infection, and that an elevated antibody level against this antigen may be a useful correlate of drug-induced cure.
Abstract: Sera from individuals living in 2 areas endemic for Schistosoma mansoni in Minas Gerais, Brazil were assayed for the presence of antibodies against paramyosin and glutathione-S-transferase (GST), molecules previously implicated as vaccine immunogens from studies in laboratory hosts. A group was identified consisting of subjects who were stool-negative and had no record of previous infection but who were seropositive by enzyme-linked immunosorbent assay against crude adult worm antigen (SWAP). These individuals had anti-paramyosin antibody levels which were dramatically elevated with respect to those measured in infected (stool-positive) individuals living in the same endemic area. In contrast, the same 2 groups of stool-positive and stool-negative subjects could not be distinguished on the basis of their seroreactivity to either GST or SWAP. After chemotherapy, anti-paramyosin antibodies rose above pre-treatment levels and remained elevated in those individuals who became stool-negative. In contrast, anti-paramyosin antibodies decreased to pretreatment values in drug-treated individuals who failed to show complete parasitological cure. These results suggest that the immune response of humans to paramyosin may play a role in natural resistance to schistosome infection, and that an elevated antibody level against this antigen may be a useful correlate of drug-induced cure.
66 citations
TL;DR: Calculation of Frandsen's (1979a, b) TCP/100 index shows that "Espinillar Biomphalaria-SJ2 S. mansoni" is a vector-parasite "compatible" combination.
Abstract: Susceptibily experiments were carried out with a Biomphalaria straminea-like planorbid snail (Biomphalaria aff. straminea, species inquirenda) from Espinillar, near Salto (Uruguay), in the area of the Salto Grande reservoir, exposed individually to 5 miracidia of Schistosoma mansoni (SJ2 and BH2 strains). Of 130 snails exposed to the SJ2 strain, originally infective to Biomphalaria tenagophila, 30 became infected (23%). The prepatent (precercaria) period ranged from 35 to 65 days. The cercarial output was irregular, following no definite pattern, varying from 138 to 76,075 per snail (daily average 4.3 to 447.5 and ending up with death. Three specimens that died, without having shed cercarie, on days 69 (2) and 80 after exposure to miracidia, had developing secondary sporocysts in their tissues, justifying the prospect of a longer precercarial period in these cases. In a control group of 120 B. teangophila, exposed to the SJ2 strain, 40 became infected, showing an infection rate (33.3%) not significantly different from that of the Espinillar snail (X [raised to the power of] 2 = 3.26). No cercarie were produced by any of the Espinilar snails exposed to miracidia of the BH2 strain, originally infective to Biomphalaria glabrata. Four specimens showed each a primary sporocyst in one tentacle, which disappeared between 15 and 25 days post-exposure, and two others died with immature, very slender sporocysts in their tissues on days 36 and 54. In a control group of 100 B. glabrata exposed to BH2 miracidia, 94 shed cercariae (94%) and 6 remained negative. Calculation of Frandsen's (1979a, b) TCP/100 index shows that "Espinillar Biomphalaria-SJ2 S. mansoni" is a vector-parasite "compatible" combination. Seeing that tenagophila-borne schistosomiasis is prevalent in Rio de Janeiro and Sao Paulo states and has recently spread sothwards to Santa Catarina state, and the range of B. tenagophila overlaps taht of the Espinillar Biomphalaria, the possibility of schistosomiais establishing itself in Uruguay, although not imminent, is not to be disregarded.
58 citations
TL;DR: Viruses similar to the bisegmented double-stranded (ds) RNA picobirnaviruses described in human faeces and the intestinal contents of Oryzomys nigripes rats and guinea pigs were isolated from the Faeces of pigs taken from several areas in the state of Sao Paulo, Brazil.
54 citations
TL;DR: Observations suggest that during differentiation, T. cruzi accumulates lipids and uses molecules contained in the reservosome as its main energy source.
Abstract: When epimastigote forms ofTrypanosoma cruzi grown in a rich medium (LIT) are transferred to a simple, chemically defined medium (TAU3AAG, containing Ca2+, Mg2+, K+, Na+,l-proline,l-glutamate, andl-aspartate in phosphate buffer, they transform into trypomastigote forms. Morphometric analysis of transmission electron micrographs of thin sections of parasites collected at different steps of the transformation process showed that no changes occurred in the volume density of mitochondria and cytoplasmic vacuoles. However, a significant increase in the volume density of the kinetoplast DNA network as well as the lipid inclusions and a decrease in that of the reservosome (a special type of endosome) was observed. These observations suggest that during differentiation,T. cruzi accumulates lipids and uses molecules contained in the reservosome as its main energy source.
52 citations
TL;DR: It is suggested that Paf‐acether‐induced Pleurisy in the rat may be mediated by lipoxygenase arachidonic acid metabolites and that pleurisy induced by zymosan, but not by carrageenin, is largely dependent upon Paf•acether.
Abstract: 1 The intrapleural injection of Paf-acether into rats caused, at 30 min, a marked exudation accompanied by a reduction in the pleural leucocyte count At 6 h, the exudate volume had decreased and a significant increase in the total leucocyte count, particularly eosinophils was noted 2 Two Paf-acether antagonists, WEB 2086 and 48740 RP abrogated the pleural leucopenia observed 30 min after Paf-acether administration, whereas the exudation was inhibited only by the former Pleurisy was also reduced by about 60% with dexamethasone, by about 45% with BW 755C or LY 171883, a mixed cyclo-oxygenase/lipoxygenase inhibitor and a peptido-leukotriene antagonist respectively, and by about 30% with indomethacin, flurbiprofen or piroxicam 3 Repeated daily intrapleural injections of Paf-acether led to a state of progressive desensitization to Paf-acether itself, whereas responsiveness to 5-hydroxytryptamine was maintained In addition, the Paf-induced auto-desensitization was largely inhibited by WEB 2086 4 Pleurisy induced by zymosan, but not by carrageenin, was significantly reduced in Paf-acether-desensitized animals These results were consistent with those obtained with WEB 2086 which suppressed zymosan-induced but not carrageenin-induced pleurisy 5 This study suggests that Paf-acether-induced pleurisy in the rat may be mediated by lipoxygenase arachidonic acid metabolites and that pleurisy induced by zymosan, but not by carrageenin, is largely dependent upon Paf-acether
TL;DR: It was discussed the parasitological comprovation difficulties in chronic chagasic patients, the value of the simultaneous utilization of different triatomine species in xenodiagnosis and the hemoculture, in a favorable positive association to the sensistivity increase in the diagnosis' disease.
Abstract: Fifty nine chronic chagasic patients were simultaneously submitted to xenodiagnosis and hemoculture for Trypanosoma cruzi sampels isolations. The xenodiagnosis was done with 40 Panstrongylus megistus, Triatoma infestans and Dipetalogaster maximus nymphs, performing 120 triatomines. Groups of 10 insects per specie were dissecated and the intestinal content pooled and examine, after previous trituration and homogenization. The microscopically negative material was seed into LIT medium and examined after 20 days. Twenty nine patients were parasitologically proved, being 15 only by senoxiagnosis, 4 only by hemoculture and 10 by both methods. It was discussed the parasitological comprovation difficulties in chronic chagastic patients, the value of the simultaneous utilization of different triatomine species in xenodiagnosis and the hemoculture, in a favorable positive association to the sensistivity increase in the diagnosis' disease. The 49,2% of posistivity obtained in this group, visualize approaches like clinic-therapeutic assay and or epidemiological (case-control) with the purpose to investigate a possible association with T. cruzi sampels and different clinic forms in Chagas' disease.
TL;DR: A detailed description of the shape of egg, external appearance of adult female and male, genitalias, female cibarial armature and complete chaetotaxy of pupa and larva show that An.
Abstract: Anopheles (Nyssorhynchus) deaneorum sp. n. is described from specimens collected in Guajara-Mirim, Rondonia state and Rio Branco, Acre state, Brazil, on human and animal baits, inside dwellings and from the progenies of engorged females. A detailed description of the shape of egg, external appearance of adult female and male, genitalias, female cibarial armature and complete chaetotaxy of pupa and larva show that it can be distinguished from Anopheles albitarsis from the type-locality and other areas by the paler general external appearance of the adult, the posterolateral tufts of scales, on the female abdominal terga and the branching of the outer anterior clypeal seta (3-C) of the fourth instar larva (as shown in illustrations). If species can also be distinguished from An. albitarsis from the type locality by the allele frequencies at 11 enzymic loci as represented by Nei's Genetic Distance.
TL;DR: The results indicated that based on this multilocus enzyme study these zymovars should be considered as belonging to the same species, B. thuringiensis and B. cereus.
Abstract: Thirty-two strains of Bacillus spp. were examined in a multilocus enzyme study by agarose gel electrophoresis. The organisms were Bacillus thuringiensis (21 strains, B. cereus (8), including two of var. mycoides, and B. megaterium (3). Strains having similar enzyme variants were grouped into zymovars. A total of 10 of 11 enzyme loci studied were polymorphic and 27 zymovars were distinguished among the 32 strains. The results were subjected to numerical analysis, phenetic affinities and genetic distances between the strains were calculated. The numerical analysis was unable to differentiate between B. thuringiensis and B. cereus. Our results indicated that based on this multilocus enzyme study these zymovars should be considered as belonging to the same species. A mycoides variant of B. cereus was the most distinctive strain studied and clearly belonged to a separate species, B. mycoides. The technique also allowed for identification of contamination and mislabelling of strains.
TL;DR: The Baermann-Moraes-Coutinho technique is adapted and the results have demonstrated that more economy of material and physical space have been obtained becoming easier to work in the laboratory and in the field.
Abstract: We have adapted the Baermann-Moraes-Coutinho's technique and the results have demonstrated that more economy of material and physical space have been obtained becoming easier to work in the laboratory and in the field. The sensitivity of the adapted technique was somewhat higher for Strongyloides stercoralis (2,8%) when compared with the original technique and 6,5% for sedimentarion methods.
TL;DR: Azadirachtin A, if applied at the dose of 1 (μg/ml), did not affect the hemolytic activity of the crop contents or the proteinase content of the intestine, and a parallel between azadIRachtin effects on the hormone balance of the host and growth inhibition of the parasite is discussed on the basis of the present results.
Abstract: The ED50 for moulting inhibition by injected azadirachtin A is for fourth instar larvae of all the triatomines, Triatoma vitticepes, T. pseudomaculata, T. maculata, T. brasiliensis, T. lecticularis, T. matogrossensis, T. infestans, Rhodnius prolixus. R. neglectus, R. robustus, Panstrongylus megistus, and P. herrera in the range of 10-25 ng/larva. In Rhodnius prolixus, the survival of T. cruzi was studied after treatment with the drug. If the trypomastigotes were fed in presence of 1.0 microgram azadirachtin A/ml blood, the number of parasites decreased near to the limit of detection within 30 days. If the drug was applied 20 days after T. cruzi infection, it still completely abolished the parasite in the host's gut within the subsequent 20 days. The same holds true if the insect larvae were pretreated with azadirachtin A 20 days before the subsequent infection with T. cruzi. Azadirachtin A. if applied at the dose of 1 microgram/ml, did not affect the hemolytic activity of the crop contents or the proteinase content of the intestine. A parallel between azadirachtin effects on the hormone balance of the host and growth inhibition of the parasite is discussed on the basis of the present results.
TL;DR: It is strongly suggested that macrophage surface areas and/or receptors are the limiting factors for optimal quantitative determination of the interaction of T. cruzi in vitro.
Abstract: A comparative and systematic analysis of the different experimental conditions used in Trypanosoma cruzi-macrophage interaction assays is presented. A pH range from 6.2 to 6.9 is favorable for parasite invasion, as is the use of Dulbecco's Modified Eagle Medium (DMEM). The washing procedures used in purification protocols also enhance the parasites' ability to penetrate macrophages. However, the main factor affecting the quantitative parameter of this in vitro infection, regardless of the parasite: cell ratio, is the number of macrophages provided to the parasites. These results, reviewed and compared with the corresponding literature, strongly suggest that macrophage surface areas and/or receptors are the limiting factors for optimal quantitative determination of the interaction of T. cruzi in vitro.
TL;DR: The chromosome pattern is strictly conserved during the transformation of T. cruzi Dm 28c epimastigotes to metacyclictrypanosomatids, suggesting that extensive chromosomal rearrangements do not occur during at least part of the life cycle of the parasite.
TL;DR: Dihydroazadirachtin A, fed in a blood meal to Rhodnius prolixus, was absorbed, transported by the haemolymph, retained, and excreted unmetabolized by the organism.
TL;DR: In this article, a small locality in the interior of the Bahia state, Brazil, 47% of sylvatic rodents were found to be naturally infected with Schistosoma mansoni, whereas the prevalence of the infection in the inhabitants of the area was 3.26%.
Abstract: UNLABELLED
In Planalto, a small locality in the interior of the Bahia state, Brazil, 47% of sylvatic rodents were found to be naturally infected with Schistosoma mansoni, whereas the prevalence of the infection in the inhabitants of the area was 3.26%. The rodents (Nectomys) live near the houses, in contact with water, passing viable schistosome eggs in the stools. Worm burden is variable amongst such rodents. Periovular granulomas are small, especially in liver and intestines, and hepatic fibrosis is mild or absent, with no morphological evidence of portal hypertension being noted. Miracidia isolated from the eggs recovered from Nectomys readly infected laboratory-raised Bahia strain of Biomphalaria glabrata. Cercariae then obtained infected Swiss mice in a similar way as the human strains of S. mansoni kept in laboratory. Also, Swiss mice left in contact with water collections in Planalto were easily infected, which proved the transmissibility potential of the area.
IN CONCLUSION
sylvatic rodents found in the area of Planalto tolerate well S. mansoni infection, eliminate viable eggs in the stools, are usually infected with a strain probably of human origin and therefore may play a role in maintaining parasite cycle in the area.
TL;DR: In this paper, the numbers of IgG secreting cells (IgG SC) were found to be significantly elevated in PCM patients, and increased serum levels of B lymphocytes, IgG, IgA and CIC.
Abstract: Paracoccidioidomycosis (PCM) is often associated with hypergammaglobulinemia and increased serum levels of circulating immune complexes (CIC). In order to investigate whether polyclonal B lymphocyte activation (PBA) is a current process in PCM, we measured the numbers of IgG secreting cells (IgG SC) in the peripheral blood of 16 patients and of 8 healthy controls. The numbers of IgG SC were found to be significantly elevated in PCM patients. We also observed increased serum levels of IgG, IgA and CIC. These data reflect an activation of B lymphocytes in PCM patients.
TL;DR: Five monoclonal antibodies from patients infected with Schistosoma mansoni are described which have different antigenic specificities for life–cycle stages based on ELISA to soluble crude antigen preparations, membrane immunofluorescence on whole intact organisms, and immun ofluorescent staining of cryostat frozen sections.
Abstract: We have produced a panel of human monoclonal antibodies (MoAb) from patients infected with Schistosoma mansoni in order to analyse more carefully the human immune response to this helminth infection. This study describes the production, characterization and analysis of these MoAbs. Briefly, peripheral blood mononuclear cells from chronically infected patients were (1) isolated and stimulated with parasite antigens in vitro, (2) positively selected for B-cells on anti-Ig columns, and (3) then transformed with Epstein-Barr virus (EBV). Once EBV cell lines were established, they were selected for anti-S. mansoni antibodies using an ELISA, cloned, retested and then fused with the mouse-human heteromyeloma SHM-D33. In this study, we describe five MoAbs which have different antigenic specificities for life-cycle stages based on ELISA to soluble crude antigen preparations, membrane immunofluorescence on whole intact organisms, and immunofluorescent staining of cryostat frozen sections. The importance of these reagents with regard to the human immune response to S. mansoni is currently being evaluated.
TL;DR: The egg of Sarcodexia lambens (Diptera: Sarcophagidae) is described on the basis of scanning electron microscopy.
Abstract: The egg of Sarcodexia lambens (Diptera: Sarcophagidae) is described on the basis of scanning electron microscopy.
TL;DR: Experiments showed that in the marsupial Didelphis mars upialis, a mammal highly resistant to the venom of Bothrops jararaca, and other BothroPS venoms, has a genetically origin protein, a alpha-1, acid glycoprotein, now highly purified, with protective action in mice against thejararaca snake venom.
Abstract: The existence of mammals and reptilia with a natural resistance to snake venoms is known since a long time. This fact has been subjected to the study by several research workers. Our experiments showed us that in the marsupial Didelphis marsupialis, a mammal highly resistant to the venom of Bothrops jararaca, and other Bothrops venoms, has a genetically origin protein, a alpha-1, acid glycoprotein, now highly purified, with protective action in mice against the jararaca snake venom.
TL;DR: Culicoides paraensis (Goeldi), a common and widespread American bloodsucking midge that has been incriminated in the transmission of Mansonellosis and Oropouche Fever of humans in South America, is redescribed and figured.
Abstract: Culicoides paraensis (Goeldi), a common and widespread American bloodsucking midge that has been incriminated in the transmission of Mansonellosis and Oropouche Fever of humans in South America, is redescribed and figured. All published records are listed and new distribution is based on examination of extensive collections from throughout its range. Three closely related species of the subgenus Haematomyidium that have been confused with C. paraensis are briefly redescribed and figured, and a key is presented for their identification.
TL;DR: Barral, Aldina Maria Prado “Documento produzido em parceria ou por autor vinculado a Fiocruz, mas nao consta a informacao no documento”.
Abstract: Barral, Aldina Maria Prado “Documento produzido em parceria ou por autor vinculado a Fiocruz, mas nao consta a informacao no documento”.
TL;DR: According to the findings, this recent plague outbreak in the Borborema Plateu focus did not exhibite different factors from those observed during prior outbreaks in other plague foci in the northeast of Brazil.
Abstract: During a plague outbreak in the Borborema Plateu focus (Paraiba), bacteriological and serological studies were carryed out in material from 452 patients (48 positives), 1,938 rodents and other small mammals (75 positives), 4,756 dogs (141 positives) and 2,047 cats (57 positives) obtained from 41 counties (out of which, 21 produced positive samples). Twenty Yersinia pestis strains isolated from material from 3 patients ans 17 rodents, displayed biochemical reactions, virulence factors, antibiotic susceptibility and animal experimental pathogenicity similar to those observed in strains previously isolated. According to our findings this recent plague outbreak did not exhibite different factors from those observed during prior outbreaks in other plague foci in the northeast of Brazil.
TL;DR: In this paper anteaters coprolites with eggs of Gigantorhynchus echinodiscus (Archiancanthocephala; Gigantorynchidae) were identified and compared with recent faeces of animals collected near the archaeological sites.
Abstract: An important point in paleoparasitology is the correct diagnosis of the origin of coprolites found in archaeological sites. The identification of human and animal coprolites, through the study of the shape, size, characteristics after rehydration, alimentary contents, and the presence of parasites, has proved to be accurate for human coprolites. For non-human ones we compared coprolites with recent faeces of animals collected near the archaeological sites, following the methodology above mentioned. In this paper anteaters coprolites (Tamandua tetradactyla; Myrmecophaga tridactyla) with eggs of Gigantorhynchus echinodiscus (Archiancanthocephala; Gigantorynchidae) were identified.