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Review of the early literature as well as more recent results show that sulfonamides possess a distinct antimalarial activity. However, when give alone, their action is less marked and slower than that of the antimalarials commonly used in the treatment of the acute attack. Combinations with pyrimethamine provide better results, even in cases of pyrimethamine and chloroquine resistance. This warrants further investigations in an attempt to develop a therapeutic agent suitable for the treatment of such resistant cases. It may also be possible with an appropriate combination of pyrimethamine with a sulfonamide to achieve a satisfactory method for suppressive treatment both in areas with and without pyrimethamine resistance. Three main points must still be carefully studied: 1) the risk of developing malaria resistance against one or both of the components of the combination. 2) The risk of developing bacterial resistance to sulfonamides if these substances are used on a large scale in too low doses. It seems indeed that antimalarial effect with the combination of sufonamides + pyrimethamine can be obtained with doses of sulfonamides which are below those usually employed in bacterial diseases. Since the range of the ratios providing potentiation is rather large, only ratios of the combination sulfonamides: pyrimethamine should be chosen in which an antfbacterial sulfonamidemia is guaranteed. 3) It goes without sayinq that, although both pyrimethamine and modem sulfonamides, when given by themselves, have proved tc possess a large margin of safety, long term administration of their combination should be careful studied from the point of view of possible side effects. Substantial evidence has already been produced to show that the long acting sulfonamide Fanasil (Ro 4-4393) given once or once weekly possesses marked schizonticidal activity against P. falciparum. Although its action is slower than that of 4-aminoquinolines, it may be useful as a second choice drug in semi-immune subjects for the therapy of falciparum malaria. Preliminary results show that, when combined with pyrimethamine, Fanasil is highly effective in suppressing fever and asexual parasitemia due to P. falciparum. Single doses of 1 g Fanasil together with 50 mg pyrimethamine seem to be adequate for the treatment of acute falciparum malaria in semi-immune patients. The onset of action of the combination is much more rapid than that of the single components. Weekly doses of 500 mg Fanasil and 25 mg pyrimeihamine appear to provide satisfactory suppressive effects against P. falciparum at least in East Africa. This combination is active on strains which do not respond satisfactorily to the standard doses of pyrimethamine and/or chloroquine and seems to have a satisfactory sporontocidal effect. Preliminary results indicate that Fanasil alone cannot be recommended for use against the other human malaria parasites. The combination with pyrimethamine appears to be much more effective. East African strains of P. malariae seem to respond better to the combination than do Malayan strains of P. vivax but further trials are required before definite assessment can be made. Fanasil by itself has no gametocytoddal or sporontocidal action but seems to potentiate the effect of pyrimethamine at least on sporogony of P. falciparum.

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Os autores descrevem, os resultados obtidos em um programa de avaliação sorológica da vacina oral, tipo Sabin, contra a poliomielite, em uma comunidade semi-rural, próxima a cidade do Rio de Janeiro. Em condições controladas 114 crianças, com idades entre 3 meses a 3 anos (Tabela 1) foram vacinadas, com vacinas trivalentes (500.000, 200.000, e 300.000 TCD50 por dose, dos tipos 1, 2 e 3 respectivamente), usando-se três doses, com intervalos de 8 semanas entre as doses. Amostras de sangue foram coletadas por punção venosa ou discos de papel de filtro, juntamente com a 1.ª e a 3.ª dose de vacina e 9 semanas após esta última dose de vacina. As taxas de conversão alcançaram (diluição de sôro 1/8) 82,7%, 98,5% e 75,4% para os tipos 1, 2 e 3 respectivamente, após três doses de vacina (Tabela 2). A distribuição de idade de indivíduos sem anticorpos após a vacinação (Tabela 3) mostra o grupo etário de 1 a 2 anos como o que apresenta a mais baixa taxa de conversão. Os autores acentuam que as condições de vida da população estudada correspondem àquelas de grandes partes da população brasileira, nas áreas rurais do país; e uma avaliação semelhante da vacina em áreas urbanas, seria desejável. Os autores sugerem ainda o aumento da quantidade de vírus do tipo 1 na vacina como medida provàvelmente eficaz na melhora das taxas de conversão em populações como a estudada. Estudos quantitativos sôbre anticorpos para Enterovírus, presentes na população estudada, estão sendo realizados e serão pròximamente apresentados.

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Os autores apresentam dados quantitativos sôbre os anticorpos presentes em vacinados com vacina oral trivalente, contra a poliomielite (Tabela 1). Apos a 3.ª dose de vacina verificou-se um aumento do título geométrico médio da população em relação aos títulos obtidos com duas doses de vacina. Infecções naturais devem ter contribuído para formação de anticorpos para poliomielite na população, ao lado da vacina. Anticorpos para enterovírus não-pólio (Coxsackie B e alguns tipos de vírus ECHO) são apresentados na Tabela II e referem-se a amostras de sôro colhidas quando da 1.ª dose de vacina. Os autores chamam a atenção para a incidência de enterovírus na região, embora poucos sejam os dados ainda disponíveis.

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Junto ao Lago da Pampulha, Belo Horizonte, MG, foram capturados (julho/72-novembro/73) 28 exemplares de Holochilus brasiliensis, dos quais 11 (39,3%) eliminavam nas fezes ovos viáveis de S. mansoni. Miracídios da cepa mencionada ("H") infectaram Biomphalaria glabrata e as cercárias obtidas também infectaram camundongos albinos, recuperando-se, ao final do experimento, 35,3% de vermes adultos. Por outro lado, cercárias de cepa humana ("LE") de S. mansoni infectaram sete exemplares de H. brasiliensis, nascidos em laboratório, recuperando-se no fim de 60 dias, 30,5% de vermes adultos. Estudos anatomapatológicos de H. brasiliensis demonstraram infecção generalizada, encontrando-se granuloma no esôfago, estômago, intestino (delgado e grosso), fígado, baço, pâncreas e linfonodos abdominais. Espessamentos fibrosos da íntima da veia porta, granulomas em espaços porta e fibrose incipiente dos espaços porta e interlobular foram lesões decorrentes da presença de ovos de S. mansoni encontrados no fígado. Em ambiente semi-natural, foi possível fechar o ciclo do S. mansoni sem direta participação humana, utilizando-se B. glabrata experimentalmente infectadas com trematódeos da cepa "LE", H. brasiliensis nascidos em laboratório e B. glabrata nascida no ambiente semi-natural estabelecido. Verificou-se que ambas as cepas ("H" e "LE") comportaram-se de maneira análoga, não sendo verificadas, também, diferenças morfológicas entre os ovos e vermes adultos de ambas. As observações, realizadas no campo e no laboratório demonstraram que o Holochilus brasiliensis é bom hospedeiro de Schistosoma mansoni. Assim, em determinadas áreas e sob certas condições ecológicas, o cricetídeo em questão poderá, efetivamente, integrar-se ao ciclo do trematódeo na natureza, independente ou paralelamente à presença do homem. Assinala-se, finalmente, que o presente trabalho relata o segundo fechamento do ciclo biológico de S. mansoni em condições ditas semi-naturais. Os primeiros estudos, entretanto, de Antunes, Milward de Andrade, Katz & Coelho4,,em 1971 e de Antunes5, em 1971 foram feitos utilizando-se o Nectomys s. squamipes.

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No Povoado de Cavunge, semi-árido da Bahia, foi realizado estudo sobre as hepatites com objetivo de avaliar a prevalência de portadores de IgG anti-VHA. Foram avaliados 891 moradores e 85,9% foram soropositivos. A prevalência foi semelhante entre os sexos. Na zona urbana houve aumento da prevalência com a idade.

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Crude antigen and semi-purified proteins from scolices of Taenia solium cysticerci were evaluated for the immunodiagnosis of human neurocysticercosis neurocysticercosis. Semi-purified proteins obtained by electrophoresis on polyacrylamide gel and by electroelution were tested by means of the immunoenzymatic reaction against sera from normal individuals and from patients with neurocysticercosis or other parasitic diseases. The 100kDa protein provided 100% sensitivity and specificity in the immunodiagnosis. When 95 or 26kDa proteins were used, 95 and 100% sensitivity and specificity were obtained, respectively. The assays involving crude antigen and sera from normal individuals or from patients with neurocysticercosis, diluted to 1:256, gave excellent agreement with those in which 100, 95 or 26kDa proteins were tested against the same serum samples diluted to 1:64. (Kappa: 0.95 to 1.00). Crude scolex antigen may be useful for serological screening, while 100, 95 or 26kDa protein can be used in confirmatory tests on neurocysticercosis-positive cases.

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INTRODUCTION: Paracoccidioidomycosis is a systemic infection caused by Paracoccidioides brasiliensis. METHODS: In this study, a semi-nested PCR for paracoccidioidomycosis diagnosis was developed. The primers ITS1 and ITS4 were used in the first reaction, while the primers MJ03 and ITS1 primer were used in the second reaction. The semi-nested PCR was used to investigate biopsies of five patients with oral lesions that resembled paracoccidioidomycosis. RESULTS: The semi-nested PCR was positive for four samples and negative for a sample from a patient later diagnosed with leishmaniasis. CONCLUSIONS: The new semi-nested PCR describe is useful for paracoccidioidomycosis diagnosis.

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INTRODUCTION: After 29 years, rabies was detected in a cat in Curitiba, southern Brazil. METHODS: The fluorescent antibody test (FAT) and mouse inoculation test (MIT) were performed on central nervous system (CNS) samples. RESULTS: Direct immunofluorescence was negative, but the biological test was positive and rabies virus was characterized as variant 4 (from Tadarida brasiliensis). CONCLUSIONS: Reappearance of rabies in domestic animals warns of sylvatic-aerial risk of infection and the necessity of monitoring bats in historically rabies-free areas.

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IntroductionThe year 2009 marked the beginning of a pandemic caused by a new variant of influenza A (H1N1). After spreading through North America, the pandemic influenza virus (H1N1) 2009 spread rapidly throughout the world. The aim of this study was to describe the clinical and epidemiological characteristics of cases of pandemic influenza in a tropical/semi-arid region of Brazil.MethodsA retrospective study analyzed all suspected cases of pandemic influenza (H1N1) 2009 reported in the Ceará State through the National Information System for Notifiable Diseases during the pandemic period between 28 April, 2009 and November 25, 2010.ResultsA total of 616 suspected cases were notified, 58 (9.4%) in the containment phase and 558 (90.6%) in the mitigation phase. Most cases were of affected young people resident in the City of Fortaleza, the largest urban center in the State of Ceará. The most frequent symptoms presented by the cases with confirmed infection were fever, cough, myalgia, arthralgia, and nasal congestion. Mortality rate was 0.0009/1,000 inhabitants and lethality was 5.6%. Deaths were observed only in the mitigation phase. Mortality rates were similar for both sexes but were higher in the age group under 5 years.ConclusionsThe study suggests that the influenza A (H1N1) pandemic in this tropical/semi-arid region had a lower magnitude when compared to states in the Southern and Southeastern regions of Brazil.

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Introduction A sero-epidemiological survey was undertaken to detect the circulation of arboviruses in free-living non-human primates. Methods Blood samples were obtained from 16 non-human primates (13 Sapajus spp. and three Alouatta caraya) that were captured using terrestrial traps and anesthetic darts in woodland regions in the municipalities of Campo Grande, Aquidauana, Jardim, Miranda and Corumbá in the State of Mato Grosso do Sul, Brazil. The samples were sent to the Instituto Evandro Chagas (IEC) in Ananindeua, Pará, Brazil, to detect antibodies against 19 species of arboviruses using a hemagglutination inhibition test (HI). Results Of the 16 primates investigated in the present study, five (31.2%) were serologically positive for an arbovirus. Of these five, two (12.5%) exhibited antibodies to the Flavivirus genus, one (6.2%) exhibited a monotypic reaction to Cacipacoré virus, one (6.2%) was associated with Mayaro virus, and one (6.2%) was positive for Oropouche virus. Conclusions Based on the positive serology observed in the present study, it was possible to conclude that arboviruses circulate among free-living primates. The viruses in the areas studied might have been introduced by infected humans or by primates from endemic or enzootic areas. Studies of this nature, as well as efficient and continuous surveillance programs, are needed to monitor viral activities in endemic and enzootic regions.

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Introduction Herein, we report a one-tube, semi-nested-polymerase chain reaction (OTsn-PCR) assay for the detection of Paracoccidioides brasiliensis. Methods We developed the OTsn-PCR assay for the detection of P. brasiliensis in clinical specimens and compared it with other PCR methods. Results The OTsn-PCR assay was positive for all clinical samples, and the detection limit was better or equivalent to the other nested or semi-nested PCR methods for P. brasiliensis detection. Conclusions The OTsn-PCR assay described in this paper has a detection limit similar to other reactions for the molecular detection of P. brasiliensis, but this approach is faster and less prone to contamination than other conventional nested or semi-nested PCR assays.

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Introduction Saint Louis encephalitis virus (SLEV) primarily occurs in the Americas and produces disease predominantly in humans. This study investigated the serological presence of SLEV in nonhuman primates and horses from southern Brazil. Methods From June 2004 to December 2005, sera from 133 monkeys (Alouatta caraya, n=43; Sapajus nigritus, n=64; Sapajus cay, n=26) trap-captured at the Paraná River basin region and 23 blood samples from farm horses were obtained and used for the serological detection of a panel of 19 arboviruses. All samples were analyzed in a hemagglutination inhibition (HI) assay; positive monkey samples were confirmed in a mouse neutralization test (MNT). Additionally, all blood samples were inoculated into C6/36 cell culture for viral isolation. Results Positive seroreactivity was only observed for SLEV. A prevalence of SLEV antibodies in sera was detected in Alouatta caraya (11.6%; 5/43), Sapajus nigritus (12.5%; 8/64), and S. cay (30.8%; 8/26) monkeys with the HI assay. Of the monkeys, 2.3% (1/42) of A. caraya, 6.3% 94/64) of S. nigritus, and 15.4% (4/26) of S. cay were positive for SLEV in the MNT. Additionally, SLEV antibodies were detected by HI in 39.1% (9/23) of the horses evaluated in this study. Arboviruses were not isolated from any blood sample. Conclusions These results confirmed the presence of SLEV in nonhuman primates and horses from southern Brazil. These findings most likely represent the first detection of this virus in nonhuman primates beyond the Amazon region. The detection of SLEV in animals within a geographical region distant from the Amazon basin suggests that there may be widespread and undiagnosed dissemination of this disease in Brazil.

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INTRODUCTION: The aim of the present study was to evaluate the presence of arboviruses from the Flavivirus genus in asymptomatic free-living non-human primates (NHPs) living in close contact with humans and vectors in the States of Paraná and Mato Grosso do Sul, Brazil. METHODS: NHP sera samples (total n = 80, Alouatta spp. n = 07, Callithrix spp. n = 29 and Sapajus spp. n = 44) were screened for the presence of viral genomes using reverse transcription polymerase chain reaction and 10% polyacrylamide gel electrophoresis techniques. RESULTS: All of the samples were negative for the Flavivirus genome following the 10% polyacrylamide gel electrophoresis analysis. CONCLUSIONS: These negative results indicate that the analyzed animals were not infected with arboviruses from the Flavivirus genus and did not represent a risk for viral transmission through vectors during the period in which the samples were collected.

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Abstract: INTRODUCTION Risk of schistosomiasis expansion to semi-arid northeastern Brazil under the influence of the Integration Project of the São Francisco River (IPSFR) was assessed. METHODS: Stool examinations of schoolchildren, epidemiological investigation, and survey of the local host snail Biomphalaria straminea were performed in five IPSFR municipalities. RESULTS Six of 4,770 examined schoolchildren were egg-positive for Schistosoma mansoni. Biomphalaria straminea was widespread, but not naturally infected with S. mansoni. Snails experimentally exposed to two laboratory S. mansoni strains yielded infection indices of 1-4.5%. CONCLUSIONS: There is evidence of active schistosomiasis transmission in the area; thus, intensive surveillance actions are required.

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Neste trabalho são estudadas as condições para a correta combinação entre o tempo de cura, acidificação e nível de sal para produzir uma semi-conserva de pescado de de água doce acondicionada em vidro, utilizando o efeito da combinalção sal/ácido. As espécies utilizadas foram jaraqui (Semaprochilodus spp.), Curimatá (Prochilodus nigricans), Dourado (Brachyplastistoma flavicans) e Pirarucu (Arapaima gigas). Na salmora de cura prelimiar o tempo indicado para se obter uma melhor textura foi de 4 semanas, a acidificação até 4,5 foi alcançada na solução contendo 5% de ácido/100 gramas de pescado e o nível adequado de sal foi de 15% (p/v). Na salmora flavorizante a proporção de ácido foi de 1% (v/v) o que torna o produto de sabor agradável, sal na concentração de 2% (p/v) e a adição de 1% de condimentos.