Showing papers by "Oswaldo Cruz Foundation published in 1981"
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TL;DR: A new species of South American planorbid snail, Biomphalaria occidentalis, is described, indistinguishable from B. tenagophila, by the characteristics of the shell and of most organs of the genital system.
Abstract: A new species of South American planorbid snail, Biomphalaria occidentalis, is described. It is indistinguishable from B. tenagophila (Orbigny, 1835), by the characteristics of the shell and of most organs of the genital system. In B. tenagophila there is a pouch on the ventral wall of the vagina (Fig. 4A, vp), absent in B. occidentalis (Fig. 3A), and on the ventral wall of the vagina (Fig. 4A, vp), absent in B. occidentalis (Fig. 3A), and the prepuce is much wider than the penial sheath, its width increasing distalward (Fig. 4, ps,pp), whereas in B. occidentalis the prepuce is wider than the penial sheath but keeps about the same width all along (Fig.3, ps, pp). The two species are biologically separate by absolute reproductive isolation. The geographical distribution of B. occidentalis is shown in Fig. 14. So far it has been found in the Brazilian states of Acre, Amazonas (?), Mato Grosso, Mato Grosso do Sul and Parana, and in Paraguay. Its type-locality is Campo Grande, state of Mato Grosso do sul, where it was collected from several biotopes related to affluents of the Aquiduana river, chiefly Corrego Prosa and Corrego Ceroula. Specimens were deposited in the following malacological collections: Instituto Oswaldo Cruz, Rio de Janeiro; Academy of Natural Sciences, Philadelphia; Museum of Zoology, University of Michigan; and British Museum (Natural History).
70 citations
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TL;DR: A new model of a fan-suction lighttrap for collecting small insects is described, being opaque it permits a high concentration of light on the opening through which the insects are sucked in.
Abstract: A new model of a fan-suction lighttrap for collecting small insects is described. Its advantages include easily obtained material, robust construction, battery operation, portability and low cost. in addition, being opaque it permits a high concentration of light on the opening through which the insects are sucked in.
51 citations
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TL;DR: Results of some experimental and human studies on the immunopathology of C. hepatica infection indicate that both sensitization and resistance are important features of that parasitic infection.
Abstract: Capillaria hepatica is considered as a parasite that only extremely rarely affects man. However, due to its high prevalence among domestic rodents and the poor housing and hygienic conditions prevailing amongst the low income part of the population, C. hepatica may develop greater chances to cause human infection which may be more important than usually assumed. That is the main reason for this review article in which some data on the biology and pathology of the parasite are presented. The results of some experimental and human studies on the immunopathology of C. hepatica infection are also reported. These indicate that both sensitization and resistance are important features of that parasitic infection.
34 citations
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TL;DR: Chemotherapy of infected persons with oxamniquine protected the community as a whole from high worm burdens for almost three years, although at this point the prevalence began to rise towards pretreatment levels.
Abstract: Oral oxamniquine was tested as a control strategy for endemic schistosomiasis in a rural area of Bahia, Brazil. Adults were treated with a single dose (12·5 to 15 mg per kg) and children (<12 years old) with a total of 20 mg per kg in two doses. The 191 (infected) persons treated represented 69% of the infected population in the study area. Follow-up stool examinations (Kato-Katz method) at one, 3, 6, 13, 25 and 33 months showed the cure rate declining from 80% at three months to 46% at 33 months. Over one half of those not cured showed a decrease in egg counts throughout the follow-up which, after 33 months, remained 66% below the pre-treatment levels. Stool examinations conducted on all study area residents during three years before chemotherapy showed the prevalence and intensity of Schistosoma mansoni infection to be high and stable. 33 months after the chemotherapy the prevalence was 41% and for infected individuals the geometric mean egg count was 121 epg, a decline of respectively 35% and 40% from pre-treatment levels for each index. Chemotherapy of infected persons with oxamniquine protected the community as a whole from high worm burdens for almost three years, although at this point the prevalence began to rise towards pretreatment levels.
32 citations
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TL;DR: An entomological survey was performed during the period of August to December, 1977 in Rio da Prata, region of Bangu, Rio de Janeiro, and the authors stress the necessity to implement control measures since there is a potential risk of visceral leishmaniasis transmission in areas near Rio de Rio city.
Abstract: An entomological survey was performed during the period of August to December, 1977 in Rio da Prata, region of Bangu, Rio de Janeiro. Manual insect capturing devices were utilized to study the peri-domiciliar area from 13 of 27 houses. The insects were captured mainly from 4 sites which were selected as being most productive. During 22 captures (73.3 hrs/person) 1585 sandflies were collected. They were identified as Lutzomya intermedia 828 (52.2%), Lutzomyia longipalpis 687 (43,1%), Lutzomyia migonei 57 (3.6%), Lutozmyia cortelezzii 5 (0.3%), Lutzomyia fischeri 5 (0.3%), Lutzomyia micropyga 3 (0.2%), Lutzomyi firmatoi 1 (0.1%), and Brumptomyia sp. 2 (0.2%). L. longipalpis were predominant at altitudes much higher than 100 merters either in chicken houses or piggeries. Most of them were collected form 6:00 to 9:00 pm, but occasionally were captured also from 3:00 to 5: pm. L. intermedia were predominant at altitudes much lower than 100 meters. They were captured more frequently in piggeries than in chicken houses, compared to L. longipalpis. The authors stress the necessity to implement control measures since there is a potential risk of visceral leishmaniasis transmission in areas near Rio de Janeiro city.
30 citations
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TL;DR: These experiments suggested that the macrophage may have an important role in the early phases of infection particularly when nonspecific stimulation is associated with specific sensitization.
Abstract: Modulation by BCG and/or cyclophosphamide of sensitization of mice with flagellar fraction (a tubulin-enriched fraction) prevented death of mice challenged with T. cruzi CL strain trypomastigotes recovered from Vero cells. A methodology was ceveloped to assay specific antigens and to determine optimal doses for sensitization and elicitation of DTH in mice. CL strain is predominantly myotropic strain which does not produce important parasitism of mononuclear phagocyte cells; these cells appear to control infection when activated in vivo. Maximum protection was seen in this study when BCG and cyclophosphamide were associated, but protection was observed also when cyclophosphamide, that prevents supressor T cells, was applied 2 days before flagellar fraction sensitization in normal mice. These experiments suggested that the macrophage may have an important role in the early phases of infection particularly when nonspecific stimulation is associated with specific sensitization. A correlation betwen delayed hypersensitivity to parasite antigens and protection was observed.
21 citations
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TL;DR: A long-term controlled field experiment is described from northeastern Brazil, in which the molluscicide Bayluscide was used as the sole means of control against Schistosoma mansoni infection.
Abstract: A long-term controlled field experiment is described from northeastern Brazil, in which the molluscicide Bayluscide was used as the sole means of control against Schistosoma mansoni infection.Bayluscide was effective in the reduction of all of the parameters used for evaluation of the disease: incidence, prevalence, intensity of the infection (egg counts) in man, snail population (dynamics and natural infection rate) and the infectivity of natural water bodies (as measured through the exposure of sentinel mice). A less pronounced reduction of the same parameters was seen in the untreated area.Comments are made on the use of molluscicides and on the present situation in schistosomiasis control in the social and economic context of northeastern Braeil.
21 citations
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19 citations
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TL;DR: Laboratory observation on the pilid Pomacea haustrum (Reeve, 1856), competitor and predator of Manson's schistosomiasis intermediate hosts, have shown that males and females reach sexual maturity after one year, copulating preferably in the morning and laying eggs at night.
Abstract: Laboratory observation on the pilid Pomacea haustrum (Reeve, 1856), competitor and predator of Manson's schistosomiasis intermediate hosts, have shown that: Males and females reach sexual maturity after one year, copulating preferably in the morning and laying eggs at night. The time spent in these acts is variable; in the case of egglaying it depends on the number of eggs to be laid. The eggs are round, about 3mm in diameter, and have a pink color that changes with the development of the embryos. With an average incubation time of 15 to 23 days and conditioned by the temperature of the environment, they resist for 5 to 6 days immersed in water without damage to th embryos and they do not need light to hatch. The newly-hatched specimens have about 2.4 x 1,7 mm of height and diameter, respectively. The specimens bred alone grow more and survive better that when in a group. They resist for at least 90 days when left dry, remaining during this period enclosed in the shell, with the operculum hermetically closed, in hydrobiosis. In this phase, death by attack of diptera-larvae may occur.
12 citations
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TL;DR: Circulating antigens were detected in sera of mice experimentally infected with a high close of Trypanosoma cruzi by reaction with sera from chronically infected mice, and a reaction was also found in urine from acutely infected mice and dogs.
Abstract: Circulating antigens were detected in sera of mice experimentally infected with a high close of Trypanosoma cruzi by reaction with sera from chronically infected mice. The immunodiffusion reaction between homologous acute and chronic sera produced four precipitation lines. By reaction with chronic mouse serum, circulating antingens were detected in sera from heavily infected hamsters, dogs, rabbits and in sera from chagasic patients. A reaction was also found in urine from acutely infected mice and dogs. Trypanosoma cruzi exoantigen was detected in trypanosome culture medium and in the supernatant of infected cell cultures. Attempts to isolate the antigens are described.
10 citations
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TL;DR: Strong correlation was observed between severe cases in 11 to 15 years oid and higher infection rates as shown by the average number of eggs of S. mansoni per gram of faeces.
Abstract: Observou-se uma correlacao direta entre as formas hepato-esplenicas, preponderantes na faixa etaria entre 11 e 15 anos com a maior intensidade de infeccao, determinada pelo numero mediano de ovos de S. mansoni por grama de fezes.
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TL;DR: During an outbreak of mucocutaneous leishmaniasis in Praia Vermelha, Ilha Grande (Great Island) in the county of Angra dos Reis, State of Rio de Janeiro, 4.192 species of Phlebotomus were collected in domestic and wild environment with the use of animal baits and other natural shelters from January 1976 to April 1977, and the Lutzomyia intermedia and L. migonei were incriminate as the probable vectors.
Abstract: During an outbreak of mucocutaneous leishmaniasis in Praia Vermelha, Ilha Grande (Great Island) in the county of Angra dos Reis, State of Rio de Janeiro, 4.192 species of Phlebotomus were collected in domestic and wild environment with the use of animal baits and other natural shelters from January 1976 to April 1977. In a total of 11 species collected, 2.493 samples of Lutzomyia intermedia, 1.594 of Lutzomyia migonei and 105 samples of other species were found. The Lutzomyia intermedia presented a higher density in human dwellings, while the Lutzomyia migonei presented better results with animal baits and chicken-coops. The sinantropism and high density found in the houses incriminate the species L. intermedia and L. migonei as the probable vectors of Mucocutaneous Leishmaniasis in Ilha Grande.
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TL;DR: The possibility of using reliable behavioural parameters in toxicity determinations of molluscicides was assessed through the development of a method based on W.H.O.O.'s CBE50 and proved capable of detecting toxic effects of the product under concentrations much lower than those obtained from conventional lethality determinations.
Abstract: The possibility of using reliable behavioural parameters in toxicity determinations of molluscicides was assessed through the development of a method based on W.H.O. standard procedures of bioassying molluscicides and involving behavioural records by time-lapse cinematogrphy. B. glabrata adults (5 7/8 ± 1/8 whorls) were subjected to different sublethal doses of copper sulfate during 24 hours and then transferred to deionized distilled water for recovery; from those records it was possible to compute: (a) frequency of climbs to surface, (b) frequency of crawlings out of water and (c) proportion of snails on the upper, middle and botton thirds of the test containers. The Litchfield-Wilcoxon test was employed in determining a reference value (called "concentration of behavioural effect of 50%" of CBE50) in relation to each parameter. The indices thus obtained - (a) 0,010, (b) 0,006 and (c) 0,029 ppm of copper - showed the freasibility of systematic uses of behavioural criteria of toxicity and also proved capable of detecting toxic effects of the product under concentrations much lower than those obtained from conventional lethality determinations. The data also showed an effect/log dose lienar relationship for all the parameters considered and revealed changes in snail activity as a consequence of the daily light cycle. Although the clarification of the ethological aspects involved in the control of schistosome hsot snails depends on the analysis of the relationships between the snail and its natural habitat, laboratory studies, carried out with accurate measuremente of the parameters related to protective modes of behaviour, can be of great value as well.
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TL;DR: The technique of enzyme electrophoresis appears to be a useful tool in vibrio taxonomy and used in conjunction with other methods may aid in the elucidation of the systematics of the genus.
Abstract: A total of 59 isolates of Vibrio cholerae, V. parahaemolyticus and V. fluvialis were studied using the techniques of enzyme electrophoresis. The enzymes used were malate dehydrogenase (E.C.I. 1.1.37) and glucose-6-phospate dehydrogenase (E.C.I. 1.1.49). The results in general confirmed classical methods of vibrio taxonomy. The three species could be separated from each other and identified by their enzyme variant types.
The term zymovar, a group of strains having similar enzyme variants, is introduced. In the V. cholerae isolates six zymovars were found. All V. cholerae serovar 01 strains were classified in the same zymovar except for some strains of environmental origin, which occurred in another zymovar. In V. fluvialis two zymovars were detected corresponding with biovars 1 and 2 of this organism. All isolates of V. parahaemolyticus gave the same enzyme type.
The technique of enzyme electrophoresis appears to be a useful tool in vibrio taxonomy and used in conjunction with other methods may aid in the elucidation of the systematics of the genus.
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TL;DR: Praziquantel was used repeatedly in an orphanage to determine its effectiveness in controlling hymenolepis infection as mentioned in this paper, and the results showed that the treatment achieved 100% cure.
Abstract: Praziquantel was used repeatedly in an orphanage to determine its effectiveness in controlling hymenolepis. At the same time, the possible mechanisms of the transmission of this parasitosis were studied. The first group examined consisted of 161 people of which 109 were the orphanage children, who varied in age from days or months to eight years, and 52 adults, employees of the institution. Stool tests of all were made about every two months, using the Hoffman, Pons and Janer method; cure control was carried out by the same method seven to fourteen days after treatment. Every two weeks, H. nana eggs were searched for under the finger nails of the children, in insects, in domestic wastes, on door knobs and refrigerator handles, and on toilet flush knobs and strings. Water collected from rinsed urinals and shower floors was also tested. Eggs and larva of helminths and protozoa cysts were found in domestic waste and cockroaches and on door knobs. H. nana eggs were found in puddles of water left on shower floors and the rinse water of urinals. Every patient whose feces had H. nana eggs was treated with a single oral 25mg/kg dose of praziquantel, taken after lunch. In the four groups treated (66 patients in all), no important side effects were observed, and follow-up indicated 100% cure. For the 5th and last treatment, a group of both positive and negative (for H. nana) people was divided into sub-groups and treated with one (25mg/kg) or two doses of the medicine for a period of four days (total: 50mg/kg). Follow-up examination two months after treatment showed that only six patients were still eliminating eggs of the parasite; all belonged to the sub-group treated with a single dose of the drug. In spite of the treatments given an of the high percentage of cure, control of hymenolepiasis was not achieved.
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TL;DR: For the first time, Lutzomyia longipalpis has been detetect in Brazil as discussed by the authors, and attention must be paid to its possible epidemiological importance in the future.
Abstract: For the firs t time i t has been detetect
Lutzomyia longipalpis a t Praia Vermelha,
a beach o f an offshore island o f the Rio de
Janeiro State (Ilha Grande), Brazil and attention
must be paid to its possible epidemiological
importance
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TL;DR: It was found that the species Lutzomyia intermedia occurred during the whole night a steady density in human dwellings, while the species Mucocutaneous Leishmaniasis migonei presented greater density at dawn, in catches with animal bait (dog).
Abstract: For the study of time frequency of the principal vectors of the Mucocutaneous Leishmaniasis in the Ilha Grande (Great Island), from 1976 to 1977 we made four catches in 24 hours with animal bait (dog) in the outdoors and five catches in just one house of the area. It was found that the species Lutzomyia intermedia occurred during the whole night a steady density in human dwellings, while the species Lutzomyia migonei presented greater density at dawn, in catches with animal bait (dog). in a 156 hours' study on monthly variation, from March 1976 to February 1977, a specie Lutzomyia intermedia appeared during the whole year, the months of April, May, October and December being those of greater density while the specie Lutzomyia migonei had a low density even disappearing in September. The high densities of the species Lutzomyia intermedia and Lutzomyia migonei indica te them as the probable vectors of the mucocutaneous leishmaniasis in Ilha Grande.
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TL;DR: Results confirmed a close relationship between the EVI and PN antibodies and chagasic infection but their presence does not appear to relate to the severity of Chagas's heart disease.
Abstract: Serum samples from 150 individuals from an area in Brazil where Chagas's disease is endemic were examined for the presence of autoantibodies (EVI and PN). Patients were divided into four groups according to the diagnostic value and prognostic significance of electrocardiographic changes. Results confirmed a close relationship between the EVI and PN antibodies and chagasic infection but their presence does not appear to relate to the severity of Chagas's heart disease.
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TL;DR: A mesangial proliferative glomerulonephritis, characterized by segmental cell proliferation and deposition of IgM in the mesangium, is probably the entity found in the early stages of mansonic schistosomiasis.
Abstract: Twenty one cases of hepatoesplenic schistosomiasis patients without clinical and laboratory evidence of renal disease, were studied by surgical biopsies using light microscopy and immunofluorescence. The cases were classified histologically as: normal pattern (6 cases); minimal changes (6 cases); and mesangial proliferative glomerulonephritis (9 cases). By the immunofluorescence microscopy using anti IgM, IgG, IgA and C3, the predominant finding in all biopsies, except the normal cases, was granular deposits of IgM in the mesangium along with C3. On the other hand, IgG was present in all cases including normal biopsies along the capillary walls. However IgG was also present in the mesangium only in cases with glomerular lesions. This finding may well be similar to that recently described as IgM mesangial nephropathy. According to our cases a mesangial proliferative glomerulonephritis, characterized by segmental cell proliferation and deposition of IgM in the mesangium, is probably the entity found in the early stages of mansonic schistosomiasis.
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TL;DR: There seems to be no correlation between RVT positives and toxin production, and preliminary observations suggest participation of the oxidase system of V. cholerae, atmospheric oxygen and perhaps selective action of Triton X-100.
Abstract: In an enzymatic reaction it was observed that lysates of Vibrio cholerae serovar 01 from human origin produced a reversal of the redox indicator while lysates of V. cholerae non-01 serovar, and 01 serovar isolated from the environment in cholera-free areas did not produce such change. This observation was utilized in a rapid visual test (RVT) which may be useful in the identification of cholera vibrios. There seems to be no correlation between RVT positives and toxin production. The composition of the media seems to be a major factor affecting the outcome of the test. The mechanism of the reaction is under study. Preliminary observations suggest participation of the oxidase system of V. cholerae, atmospheric oxygen and perhaps selective action of Triton X-100.
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TL;DR: A correlation was verified between methods of detection and extration procedures, resulting in a better association of the extract obtained by agitation in 3M KCl and immunoelectroomophoresis.
Abstract: Solubilization of Schistosoma mansoni antigens was obtained by agitation of adult worms in a 3M KCl solution. The protein contents of the KCl extrats varied from 0.35 to 0.96 mg/ml. Sera from 97 patients with hepatointestinal shistosomiasis and viable eggs in stools from a Brazilian endemic area were studied by immunoelectroomophoresis and Ouchterlony immunodiffusion methods with the KCl extract and with another antigen, obtained by homogenization of adult schistosomes in saline. The rate of positiveness of immunoprecipitation deterctions by immunoelectroomophoresis with the KCl extract was 53.5%. A correlation was verified between methods of detection and extration procedures, resulting in a better association of the extract obtained by agitation in 3M KCl and immunoelectroomophoresis.
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TL;DR: A eficacia de termofosfato magnesiano na alimentacao de planorbideos, em laboratorio, foi testada, verificando o crescimento da concha de populacoes experimentais de Bimphalaria glabrata e Helisoma duryi, y observou que aquele produto mineral bloqueou a oviposicao de ambas as especies.
Abstract: A eficacia de termofosfato magnesiano (fertilizante e corretivo do solo) na alimentacao de planorbideos, em laboratorio, foi testada ao longo de cinco semanas, verificando-se o crescimento da concha de populacoes experimentais de Bimphalaria glabrata (Say, 1818) e Helisoma duryi (Wetherby, 1879). Reversamente observou-se que aquele produto mineral bloqueou a oviposicao de ambas as especies, a partir da segunda semana do experimento, quando proporcionado, isoladamente ou associado, a latoso ou a folhas de alface. Em consequencia, supoe-se que sua ampla utilizacao nas novas areas de cultivo, obtidas atraves de metodos modernos de irrigacao, podera, adicionalmente - ao ser carreado pelas chuvas, para ecossistemas lenticos ou loticos - reduzir as populacoes pioneiras de diferentes especies de Bimphalaria constituindo-se util meio de controle da esquistossomose mansoni, em zonas rurais. Ademais, podera ser eficaz no controle dos hospedeiros intermediarios de Schistosoma mansoni que, usualmente, se estabelecem em lagoas de criacao de peixes - cuja multiplicacao, em areas tropicais, vem sendo incentivada, quer como atividade economica alternativa para o pequeno proprietario rural quer como exigencia de necessidade nutricional das comunidades humanas mais pobres. Supoe-se, ainda, que o material testado podera controlar populacoes de limneideos, hospedeiros intermediarios de Fasciola hepatica. Sao sugeridos testes de campo que possam efetivamente comprovar a hipotese levantada, e tambem estudos destinados ao conhecimento do mecanismo de acao do elemento magnesio no bloqueio da fertilidade de moluscos. Salienta-se a necessidade de pesquisas especiais sobre o efeito de diferentes concentracoes de magnesio em ovos e formas juvenis de planorbideos, bem como sobre miracidios e cercarias (intra-caramujos e livre-natantes) de trematodeos.
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TL;DR: A new Brazilian simuliid species, Simulium (Chirostilbia) dekeyseri, is described from reared adults as well as larvas and pupae.
Abstract: A new Brazilian simuliid species, Simulium (Chirostilbia) dekeyseri, is described from reared adults as well as larvas and pupae. This zoophilic species has only been recorded from localities in the Cerrado region of the Central Brazilian Plateu.
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TL;DR: Two species of trematodes recovered from nectomys squamipes from Goias State, Brazil are presented and Amphimerus lancea, originally described from a cetacean host, is for the first time referred in a rodent.
Abstract: In this paper two species of trematodes recovered from nectomys squamipes from Goias State, Brazil, are presented. Maritremopsis mariettavogeae sp. n. is compared to M. proxilum (Caballero & Montero-Gei, 1961) and M. belopolskaiae (Caballero, 1964). Amphimerus lancea originally described from a cetacean host, is for the first time referred in a rodent.
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TL;DR: Serum protein abnormalities were examined in six kala-azar (KA) patients, six controls with positive immunofluorescence tests with Leishmania donovani antigens, and six seronegative controls.
Abstract: Serum protein abnormalities were examined in six kala-azar (KA) patients, six controls with positive immunofluorescence tests with Leishmania donovani antigens, and six seronegative controls. KA patients were clearly distinguishable from controls by several parameters, including A/G ratio, albumin and globulin levels, IgM and IgG titers, and positive rheumatoid factor (RF) tests. A positive relationship was noted between RF titers and serum levels of IgM. The diagnostic value and possibel pathologic significance of serum abnormalities in KA is discussed.