Showing papers by "Oswaldo Cruz Foundation published in 1984"
TL;DR: Epimastigote multiplying extracellularly and metacyclic trypomastigotes, stages that correspond to the cycle of Trypanosoma cruzi in the intestinal lumen of its insect vector, were consistently found in theLumen of the anal glands of opossums Didelphis marsupialis inoculated subcutaneously with infective feces of triatomid bugs.
Abstract: Epimastigotes multiplying extracellularly and metacyclic trypomastigotes, stages that correspond to the cycle of Trypanosoma cruzi in the intestinal lumen of its insect vector, were consistently found in the lumen of the anal glands of opossums Didelphis marsupialis inoculated subcutaneously with infective feces of triatomid bugs.
137 citations
TL;DR: The effects of azadirachtin on the development of 4th-instar nymphs of Rhodnius prolixus were studied using antifeedant effect and ecdysis inhibition as effective parameters.
90 citations
83 citations
TL;DR: From the data collected, it is believed that seasonal distribution of local species of Culicidae was directly influenced by three relevant climatological factors, in this order: rainfall, relative humidity and temperature.
Abstract: Em prosseguimento aos estudos sobre a ecologia de culicideos que vimos realizando no Parque Nacional da Serra dos Orgaos (PNSO), apresentamos nesta oportunidade a sua distribuicao vertical. Por meio de capturas feitas em isca humana concomitantemente ao nivel do solo e nas imediacoes da copa das arvores, estabelecemos as tendencias das especies que ali ocorreram de marco de 1981 a fevereiro de 1982, por se alimentarem de sangue na copa da floresta ou junto ao solo. A distribuicao e analisada comparativamente em ambos os niveis levando-se em consideracao as variacoes de temperatura, umidade, precipitacoes pluviometricas e estacoes do ano. Dentre as especies com nitida preferencia a acrodendrofilia encontramos alguns importantes transmissores de doencas: Anopheles cruzii - malaria humana e simiana; Culex nigripalpus - encefalite de Sao Luis (SLE); Haemagogus leucocelaenus e Haemagogus capricornii - febre amarela silvestre, todas tambem sendo obtidas, embora em menor numero, a nivel do solo. Os sabetineos - Wyeomyia Knabi, Phoniomyia theobaldi, Sabethes tarsopus, Sabethes quasicyaneus, Sabethes chloropterus - completam a relacao das principais especies que preferem a copa. Por outro lado, Aedes fluviatilis, Trichoprosopon digitatum, Tr. similis, Tr. frontosus, Tr. theobaldi, Wy, arthrostigma, Wy. aporonoma, Wy. personata, Wy undulata, Wy. mystes, Limatus durhami, Li. pseudomethisticus, Sa. identicus e Sa. undosus foram capturados em grande maioria proximo ao solo.
78 citations
TL;DR: An opossum, Didelphis albiventris, from Jacobina, Bahia State, was found naturally infected with Leishmania donovani, being the first non-canid wild mammal to be detected with the agent of kala-azar in the New World.
Abstract: An opossum, Didelphis albiventris, from Jacobina, bahia State, was found naturally infected with Leishmania donovani, being the first non-canid wild mammal to be detected with agent of kala-azar in the New World
74 citations
TL;DR: During two full years - from October 1981 to September 1983 - the authors captured sandflies using light traps in the National Park of Serra dos Orgaos, state of Rio de Janeiro, Brazil, where the sandflies were more numerous during the new moon that at full moon.
Abstract: During two full years - from October 1981 to September 1983 - we captured sandflies using light traps in the National Park of Serra dos Orgaos, state of Rio de Janeiro, Brazil. The traps were strategically located in the forest once every week, in the same place, from 6 p.m to 6 a.m. on the next day. In 732 hours, 2,730 sandflies of 17 species were collected, four of the species belonged to the genus Brumptomyia Franca & Parrot, 1921 and 13 to the genus Lutzomyia Franca, 1924. Males accounted for 76.3% of all specimens. L. barrettoi, L. ayrozai and L. hirsuta corresponded to 95% of the total and the first was almost twice as numerous as the other two taken jointly. L. ayrozai was more abundant in the warm wet season, L. hirsuta in the cold dry sease, which was the only part of the year when L. barrettoi could be found. The number of species and specimens was greater in an area (B) where the traps were placed near the ground, close to wild animal burrows, than in another area (A) in which the traps were located far from the ground with thick vegetation and trees with tubular roots. We believe that after feeding the females are attracted to the source of light, because a considerable number of pregnent specimens were found in the traps. As we had previously observed in captures using human baits, the sandflies were more numerous in the light traps during the new moon that at full moon.
68 citations
TL;DR: The authors emphasize the necessity of searching for the infection in donkeys and of performing hemocultures and xenodiagnosis with sandflies in human, canine and equine cases, to verify their possible role as sources of infection, and not merely as dead ends in the epidemiological chain of the disease.
Abstract: During an outbreak of cutaneous leishmaniasis in a locality (Las Rosas, Cojedes State, Venezuela) previously non-endemic, 12.9% of humans, 7% of dogs and 21.4% of donkeys (Equus asinus) had lesions with parasites. The agent in the three hosts was identified as Leishmania braziliensis, subspecies braziliensis at least in man and donkey. The probable vector was Lutzomyia panamensis. No infection was found in a small sample of wild mammals examined. The outbreak was apparently linked with the importation of donkeys with ulcers, from endemic areas. The authors call attention to the fact that not only in the foci of "uta", but also in areas of the other forms of American cutaneous leishmaniasis, dogs are frequently found infected. They emphasize the necessity of searching for the infection in donkeys and of performing hemocultures and xenodiagnosis with sandflies in human, canine and equine cases, to verify their possible role as sources of infection, and not merely as dead ends in the epidemiological chain of the disease.
64 citations
TL;DR: Coprolites from an archaeological site in the province of Iquique, northern Chile, were examined for parasites and the presence of this tapeworm, a parasite of the American Sea Lion, in human coprolites points to a diet which included marine fishes and provides information on the antiquity of infection by Diphyllobothrium pacificum.
Abstract: Twenty six coprolites from an archaeological site in the province of Iquique, northern Chile, were examined for parasites. Coprolites were found in two excavation units, I and II (Tiliviche site), dated respectively at 5,900 B.C. to 4,110 B.C. and 4,110 B.C. to 1,950 B.C., and identified as of human origin. Only at the unit II coprolites containing helminth eggs identified as Diphyllobothrium pacificum were found. The presence of this tapeworm, a parasite of the American Sea Lion, in human coprolites, points to a diet which included marine fishes and provides information on the antiquity of infection by Diphyllobothrium pacificum. It is interesting to note that Baer (1969) suggests the presence of this tapeworm in pre-Columbian populations when diagnosing the first human cases in today's population in Peru.
52 citations
TL;DR: It is shown that females of Anopheles cruzi move from canopy to ground and vice-versa to feed, which suggests that in areas where this mosquito is a vector of human and simian malarias sporadic infections of man with monkey plasmodia might be expected.
Abstract: By staining females of Anopheles cruzi with fluorescent coloured powders in a forest in the State of Santa Catarina, we showed that they move from canopy to ground and vice-versa to feed. This suggests that in areas where this mosquito is a vector of human and simian malarias sporadic infections of man with monkey plasmodia might be expected.
50 citations
TL;DR: A close association between eosinophils and parasitized macrophages was seen in the chronic lesions; thus, eos inophils might contribute to parasite destruction through co‐operation with macrophage.
Abstract: Outbred albino mice were infected subcutaneously with 10(6) amastigotes of Leishmania mexicana mexicana and the subsequent lesions were evaluated by light and electron microscopy at various intervals after infection. The animals developed persistent nodules and a spectrum of lesions of variable size which was correlated with the host's ability to control the parasite in the tissue. During the acute phase of the disease the histopathological results showed an accumulation of granulocytes, some mononuclear phagocytes and a predominance of eosinophils as compared to other cell types. In this early acute phase, eosinophils were found in the tissue together with normal and degranulating mast cells. In the granulomatous inflammatory reaction of the chronic phases, there was infiltration of granulocytes parallel to parasite multiplication and the formation of parasitized vacuolated macrophages. The number of eosinophils was consistently greater than neutrophils, regardless of lesion type or number of parasites present in the tissue. During the acute reaction, the granulocytes apparently destroyed many parasites; however, there was an unvaryingly low level of phagocytosis of amastigotes during the chronic stages by both eosinophils and neutrophils. Neutrophils seemed to be more effective than eosinophils in the killing of ingested parasites. A close association between eosinophils and parasitized macrophages was seen in the chronic lesions; thus, eosinophils might contribute to parasite destruction through co-operation with macrophages.
50 citations
TL;DR: The mechanisms of feeding and molt inhibitions by azadirachtin A B, and its 7-acetyl-azadirachin A derivative are discussed, and the antifeedant and antimolting effects of these compounds were examined.
Abstract: Abstract The antifeedant and antimolting effects of azadirachtins A and B, and of a synthetic derivative, 7-acetyl-azadirachtin A were examined. Given through a blood meal, the effective dose (ED50) for the antifeedant effect ranged from 25 to 30 μg/ml of blood for the three compounds. ATP, a phagostimulant, also given orally, reversed the antifeedant action of azadirachtin A. The ED50 values for molt inhibition were 0.04, 0.015, and 0.45 (μg/ml of blood for azadirachtins A, B, and 7-acetyl-azadirachtin A, respectively. The mechanisms of feeding and molt inhibitions by azadirachtin A B, and its 7-acetyl-azadirachtin A derivative are discussed.
TL;DR: A method is described which permits to determine in vivo and in a short period of time the sensitivity of T. cruzi strains to known active chemotherapeutic agents and may be used to characterize susceptibility to active drugs used clinically, provide information on the specific action against circulating trypomastigotes and screen active compounds.
Abstract: A method is described which permits to determine in vivo and in a short period of time (4-6 hours) the sensitivity of T. cruzi strains to known active chemotherapeutic agents. By using resistant- and sensitive T. cruzi strains a fairly good correlation was observed between the results obtained with this rapid method (which detects activity against the circulating blood forms) and those obtained with long-term schedules which involve drug administration for at least 20 consecutive days and a prolonged period of assessment. This method may be used to characterize susceptibility to active drugs used clinically, provide information on the specific action against circulating trypomastigotes and screen active compounds.
TL;DR: Over a period of one year (May, 1980 to April, 1981), systematic collections of Sarcophagidae were made in three ecologically distinct areas of Belo Horizonte, Minas Gerais, using two types of traps and five types of bait to capture specimens.
Abstract: Com o objetivo de se conhecer a fauna de Sarcophagidae da regiao de Belo Horizonte, Minas Gerais, e se obter dados sobre seu comportamento, foram realizadas capturas sistematicas em tres areas ecologicamente distintas, pelo periodo de um ano (maio de 1980 a abril de 1981). Para as capturas, foram utilizadas dois tipos de armadilhas apropriadas e cinco tipos de iscas; peixe cru, carcaca de camundongo, v´sceras de galinha, banana amassada com rapadura e fezes humanas. Foi capturado um total de 10.097 especimens, dos quais foram estudados 9.582 exemplares, representados por 25 especies. O indice de sinantropia foi determinado segundo a metodologia de Nuorteva (1963). Foram obtidos indices variaveis de sinantropia para as 25 especies analisadas, sendo as mais sinantropicas Parasarcophaga ruficornis (IS = + 94,7) e Bercaea haemorrhoidalis (IS = + 84,3), e as mais assinantropicas Euboettcheria florencioi (IS = - 98,8) e Oxysarcodexia augusta (IS = - 96,9).
TL;DR: The animal model appears worthwhile for the study of the healing process in conducting tissue of the heart and for the better understanding of the asymptomatic phase of T. cruzi infection in man.
Abstract: The consequences of acute inflammatory damage and chronic repair in the conducting system of the canine heart were observed after experimental Trypanosoma cruzi infection of young dogs. Acute infection lasted for 18-25 days and caused hyaline and lytic necrosis of the atrio-ventricular conducting fibres, the sinus node and the neurons in the cardiac para-sympathetic ganglia. Dogs that survived acute disease were examined after periods from 8 months to 3 years. Three main types of healing were found in the conducting system: fibrosis (diffuse and/or focal), sclero-atrophy and fatty infiltration. No signs of active chronic inflammation were present, although small focal residual accumulations of mononuclear cells were present in some animals. No evident electrocardiographic alterations were elicited by the presence of such cicatricial lesions. The animal model appears worthwhile for the study of the healing process in conducting tissue of the heart and for the better understanding of the asymptomatic phase of T. cruzi infection in man.
TL;DR: Schistosomal glomerulopathy is defined as an immune-complex disease that appears in 12-15 per cent of the individuals with hepatosplenic schistosomiasis and can be experimentally produced, and schistsosomal antigens and antibodies, as well as complement, can be demonstrated in the glomerular lesions.
Abstract: In this review paper schistosomal glomerulopathy is defined as an immune-complex disease. The disease appears in 12-15 per cent of the individuals with hepatosplenic schistosomiasis. Portal hypertension with collateral circulation helps the by pass of the hepatic clearance process and the parasite antigens can bind to antibodies in the circulation and be trapped in the renal glomerulus. Chronic membranous-proliferative glomerulonephritis is the most common lesion present and the nephrotic syndrome is the usual form of clinical presentation. The disease can be experimentally produced, and schistosomal antigens and antibodies, as well as complement, can be demonstrated in the glomerular lesions. Specific treatment of schistosomiasis does not seem to alter the clinical course of schistosomal nephropathy.
TL;DR: The results illustrate strain selection through laboratory manipulation of initially mixed populations of T. cruzi through biological and biochemical methods.
Abstract: From an initial double infection in mice, established by simultaneous and equivalent inocula of bloodstream forms of strains Y and F of Trypanosoma cruzi, two lines were derived by subinoculations: one (W) passaged every week, the other (M) every month. Through biological and biochemical methods only the Y strain was identified at the end of the 10th and 16th passages of line W and only the F strain at the 2nd and 4th passages of line M. The results illustrate strain selection through laboratory manipulation of initially mixed populations of T. cruzi.
TL;DR: As plantas que demonstraram acao moluscicida na concentracao de 100 ppm foram: Arthemisia verlotorum Lamotte, Caesalpinia peltophoroides Benth, Cassia rugosa G.Don, Macrosiphonia guaranitica Muell, Palicourea nicotianaefolia Cham, e Schlech.
Abstract: Estudou-se em laboratorio a atividade moluscicida de 68 extratos de 23 plantas brasileiras. As solucoes em agua desclorada dos extratos hexânicos e etanolico, nas concentracoes de 1, 10 e 100 ppm, foram testadas sobre caramujos adultos e desovas de Biomphalaria glabrata, criados em laboratorio. As plantas que demonstraram acao moluscicida na concentracao de 100 ppm foram: Arthemisia verlotorum Lamotte, Caesalpinia peltophoroides Benth, Cassia rugosa G.Don., Eclipta alba Hassk, Euphorbia pulcherrima Willd, Euphorbia splendens Bojer, Joannesia princeps Vell, Leonorus sibiricus L.,Macrosiphonia guaranitica Muell,Nerium oleander L., Palicourea nicotianaefolia Cham, e Schlech., Panicum maximum M., Rumex crispus L., Ruta graveolens L., e Stryphnodendron barbatiman M.
TL;DR: The Authors verified that the basal tuft of the coxite is composed of only four foliaceous setae, and not six, as stated by Mangabeira, due the superposition of the two coxites holotype.
Abstract: After examining the type of Lutzomyia (Lutzomyia) cruzi (Mangabeira, 1938), kept in the collection of the Instituto Oswaldo Cruz (Rio de Janeiro), under number 941, and 74 male specimens of the species, mostly from the type locality (Camapuan, State of Mato Grosso do Sul), the Authors verified that the basal tuft of the coxite is composed of only four foliaceous setae, and not six, as stated by Mangabeira, due the superposition of the two coxites holotype. A redescription of the male based on the holotype and a description of the previously unknown female are presented.
TL;DR: The, taxonomic status of the Brazilian species Anthobothrium pristis, A. piramutab, and A. karuatayi has been reappraised and the others, from siluroid teleosts, are transferred to Proteocephalidea.
Abstract: The, taxonomic status of the Brazilian species Anthobothrium pristis, A. piramutab, A. mandube and A. karuatayi has been reappraised. A. pristis from an elasmobranch in the Amazon, is confirmed as a member of the tetraphyllidean genus Anthobothrium, but the others, from siluroid teleosts, are transferred to Proteocephalidea. A. piramutab is transferred to Proteocephalus as a new combination. Gibsoniela n.g. is erected in Zygobothriinae for A. mandube and Brayela n.g. is erected in a new subfamily, Brayelainae for A. Karuatayi.
TL;DR: The unique deaths and the more severe pulmonary lesions were found among the intact females, representing the animals most susceptible to the infection in these experiments.
Abstract: The development of intraperitoneal paracoccidioidomycosis was studied in groups of female and male rats: a) U nder normal conditions (intacts), b) After castration and c) After castration but submitted to a treatment with, respectively, testosterone and estradiol.
TL;DR: In an attempt to clarify the taxonomy of Neotropical Simuliidae prior to the production of keys to species, various nomenclatural problems are resolved.
Abstract: In an attempt to clarify the taxonomy of Neotropical Simuliidae prior to the production of keys to species, various nomenclatural problems are resolved. Information is given on the status of types, their depositories, the condition of type-material where relevant, and on already established synonyms. fifteen new synonyms are established and six lectotypes designated based on an examination of type-material and long series of reared specimens from many localities to take account of intraspecific variation.
TL;DR: In this article, a distribuicao sazonal da Sarcophagidae was presented, with a total of 10.097 especimes, of which 9.582 representados by 25 especies, foram estudados e analisados.
Abstract: Visando contribuir para o conhecimento da biologia de algumas especies de Sarcophagidae da regiao de Belo Horizonte, Minas Gerais, realizamos capturas sistematicas pelo periodo de um ano (maio de 1980 a abril de 1981). Para isto utilizamos armadilhas e iscas atrativas adequadas para a captura destes dipteros. Foi capturado um total de 10.097 especimes, dos quais 9.582, representados por 25 especies, foram estudados e analisados sob diferentes aspectos. neste trabalho apresentamos a distribuicao sazonal da familia Sacophagidae, bem como a distribuicao anual observada para cada uma das 25 especies.
TL;DR: Symptoms and radiographic abnormalities suggestive of esophageal motility disorders with electrocardiographic alterations and seroreactivity to Trypanosoma cruzi was studied in a defined population in a rural area endemic for Chagas' disease in Bahia, Brazil.
Abstract: The relationship of symptoms and radiographic abnormalities suggestive of esophageal motility disorders with electrocardiographic (ECG) alterations and seroreactivity to Trypanosoma cruzi was studied in a defined population in a rural area endemic for Chagas' disease in Bahia, Brazil. Between January and June 1981, 680 individuals 5 years of age or older were examined with serologic tests, ECGs and questionnaires for esophageal motility disorder. Of these, 39.9% were seropositive for Chagas' disease. Symptoms of dysphagia occurred 2.5 times more frequently among seropositive individuals than among seronegative individuals. Radiographic esophageal abnormalities were 3.6 times more frequent among seropositive individuals than among seronegative individuals in the symptomatic group. Symptoms and radiographic abnormalities were more common in men than in women although this was not statistically significant. Among seropositive individuals the percentage with symptoms of dysphagia increased with age, with a peak prevalence rate of 23.9% in the 45- to 64-year-old age group. Also, in the seropositive group, 41.7% with X-ray abnormalities of the esophagus and 26.3% with symptoms of dysphagia presented an abnormal ECG.
TL;DR: A complete description of the adults, pupa and larva of S. brachycladum is given and a lectotype selected for this species and the similarity between S. rubrithorax and S. paynei is studied.
Abstract: A complete description of the adults, pupa and larva of S. brachycladum is given and a lectotype selected for this species. The similarity between S. brachycladum and S. rubrithorax is extensively covered from S. rubrithorax. The taxonomic position of S. rubrithorax within the subgenus Hemicnetha is studied, a neotype is selected for this species and S. conviti is sunk as a synonym of S. paynei; and a lectotype is selected for S. paynei.
TL;DR: Seven species of the Bolboderini tribe belonging to the genera bolbodera, Belminus, Microtriatoma and Parabelminus, two of them found naturally infected with Trypanosoma cruzi, were analysed and compared to confirm the affinity between Microtri atoma andParabelminus and their relations with Belminus and BolbodERA.
Abstract: Seven species of the Bolboderini tribe belonging to the genera bolbodera, Belminus, Microtriatoma and Parabelminus, two of them found naturally infected with Trypanosoma cruzi, were analysed and compared emphasizing eight structures of the male external genitalia: median process of pygophore (PrP), conjunctiva process (PrCj), pedicel (EP1b), endosoma process (PrEn), struts (SPh), phallosoma (Ph), medium bridge (PrG) and vesica (V). Microtriatoma trinidadensis (Lent, 1951) and M. borbai Lent & Wygodzinsky, 1979 have shown a structural morphological aspect similar to Parabelminus yurupucu Lent & Wygodzinsky, 1979 and P. carioca Lent, 1943 differing clearly from Belminus peruvianus Herrer, Lent & Wygodzinsky, 1954, B. herreri Lent & Wygodzinsky, 1979 and Bolbodera scabrosa valdes, 1910, not only by the absence but by the shape of some structures. These comparative observations confirm the affinity between Microtriatoma and Parabelminus and their relations with Belminus and Bolbodera.
TL;DR: Systematic collection of Sarcophagidae was made between May 1980 and April 1981 with two types of traps and five different baits, finding that attractiveness of baits is correlated to climatic conditions.
Abstract: Systematic collection of Sarcophagidae was made between May 1980 and April 1981 with two types of traps and five different baits. Twenty-five species were represented amingst the 9,592 specimens identified. The results are analysed to determine the attractiveness of different baits for Sarcophagidae in general and for each of the species obtained. For the commonest species, attractiveness of baits is correlated to climatic conditions.
TL;DR: Two new foci of transmission of Schistosoma mansoni in the state of Para are recorded, with the finding of naturally infected Biomphalaria glabrata in the municipalities of Viseu and Belem.
Abstract: Two new foci of transmission of Schistosoma mansoni in the state of Para are recorded, with the finding of naturally infected Biomphalaria glabrata in the municipalities of Viseu and Belem. Uninfected specimens of Biomphalaria straminea, as well as the planorbid species Biomphalaria schrammi, Drepanotrema lucidum and D. anatinum, were found in the same area.