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  1. Trypanocidal activity of human plasma on Trypanosoma evansi in mice Atividade tripanocida do plasma humano sobre Trypanosoma evansi em camundongos

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    Aleksandro Schafer Da Silva

    2012-03-01

    Full Text Available This study aimed to test an alternative protocol with human plasma to control Trypanosoma evansi infection in mice. Plasma from an apparently 27-year-old healthy male, blood type A+, was used in the study. A concentration of 100 mg.dL-1 apolipoprotein L1 (APOL1 was detected in the plasma. Forty mice were divided into four groups with 10 animals each. Group A comprised uninfected animals. Mice from groups B, C and D were inoculated with a T. evansi isolate. Group B was used as a positive control. At three days post-infection (DPI, the mice were administered intraperitoneally with human plasma. A single dose of 0.2 mL plasma was given to those in group C. The mice from group D were administered five doses of 0.2 mL plasma with a 24 hours interval between the doses. Group B showed high increasing parasitemia that led to their death within 5 DPI. Both treatments eliminated parasites from the blood and increased the longevity of animals. An efficacy of 50 (group C and 80% (group D of human plasma trypanocidal activity was found using PCR. This therapeutic success was likely achieved in the group D due to their higher levels of APOL1 compared with group C.Este estudo teve como objetivo testar um protocolo alternativo com plasma humano para controlar a infecção por Trypanosoma evansi em camundongos. O plasma foi oriundo de um homem aparentemente saudável, com idade entre 27 anos e tipo de sangue A+. Foi detectada uma concentração de 100 mg.dL -1 de apolipoproteína L1 (APOL1 no plasma. Quarenta camundongos foram divididos em quatro grupos, contendo dez animais cada. Grupo A, composto de animais não infectados. Os roedores dos grupos B, C e D foram inoculados intraperitonealmente com um isolado de T. evansi. O Grupo B foi usado como um controle positivo. Três dias pós-infecção (DPI, os camundongos foram tratados com plasma humano. Uma dose única de 0,2 mL de plasma foi administrada nos roedores do grupo C. Os ratos do grupo D receberam cinco

  2. Infecção via oral por Trypanosoma evansi em animais de laboratório Oral infection by Trypanosoma evansi in rats and mice

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    Aleksandro Schafer da Silva

    2007-06-01

    Full Text Available Testou-se a infecção de Trypanosoma evansi pela via oral em ratos e camundongos, através de sangue contaminado de ambas as espécies. Dez ratos e dez camundongos foram alocados em quatro grupos iguais A e B (ratos, C e D (camundongos. Os grupos A e C receberam sangue contaminado de um rato e o grupo B e D de um camundongo, através de uma sonda. O volume de sangue administrado foi de 0,2ml, o qual apresentava uma concentração de 10(7 tripanossomas ml-1. Os animais foram mantidos em temperatura e umidade constantes (25°C e 80% UR, sendo realizados esfregaços sanguíneos diários para identificar o período pré-patente e a evolução do parasita na circulação. Nos grupos A e B, o período pré-patente variou de 19 a 25 dias, e o período entre a detecção dos parasitas e a morte dos animais foi em média de 12,7 dias. Os camundongos do grupo C e D não apresentaram infecção pelo parasita, sendo estes avaliados por 60 dias. Os ratos foram susceptíveis a infecção por T. evansi pela via oral; entretanto, os camundongos não se contaminaram com o protozoário por via digestiva.In this research, Trypanosoma evansi infection was tested in rats and mice by oral ingestion of contaminated blood. Groups of ten rats and ten mice were disposed in four experimental groups: A and B (rats, C and D (mice. The groups A and C were contaminated by rat-contaminated blood; B and C groups by mouse-contaminated blood. The blood was given using a probe filled with 0.2ml of contaminated blood with 10(7 trypanosomes ml-1. These animals were maintained at constant temperature and humidity (25°C and 80% UR. Dairy blood smear were done to identify the prepatent period and evolution of parasite in the circulation. In the A and B groups, the pre latency period varied from 19 to 25 days and the period of parasite detection and animals death was an average of 12.7 days. The C and D groups did not present infection by the parasite even when evaluated for 60 days

  3. Estudo sorológico de infecções experimentais por Trypanosoma evansi, em cobaias

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    Teresa Cristina Goulart de Oliveira

    1989-04-01

    Full Text Available Comparamos os métodos de Imunofluorescência Indireta (IFI, Imunodifusão Radial Dupla e Aglutinação, para a pesquisa de anticorpos em soros, na tripanossomíase experimental por Trypanosoma evansi, em cobaias. Foram obtidas 20 amostras de soro correspondentes às 4 primeiras semanas de infecção. A IFI foi positiva em apenas 6 animais, com títulos variando de 1:4 a 1:16. Os títulos mais altos foram observados na 3ª semana pós-infecção. Anticorpos aglutinantes foram observados a partir da 1ª semana pós-infecção e, após a 2ª semana, todos os animais apresentaram reação de aglutinação positiva, com títulos variando de 1:8.000 a 1:250.000. O tratamento dos soros com 2-Mercapto-etanol inibiu a reação de aglutinação, sugerindo ser IgM a principal classe dos anticorpos presentes no soro dos animais infectados. Não se constatou a presença de anticorpos precipitantes durante todo o curso da infecção.

  4. Resposta eritropoética de ratos em diferentes graus de parasitemia por Trypanosoma evansi Erithropoietic response in Trypanosoma evansi infected rats with different parasitaemia intensity

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    Patrícia Wolkmer

    2007-12-01

    Full Text Available O Trypanosoma evansi é um protozoário hemoflagelado que causa, em várias espécies, uma doença caracterizada por altos níveis de parasitemia, com rápido desenvolvimento de anemia. Este trabalho teve como objetivo investigar a relação entre o grau de parasitemia e a alteração na eritropoese de ratos (Rattus norvegicus da linhagem Wistar infectados experimentalmente com T. evansi. Foram utilizados 42 ratos, dos quais 36 foram inoculados pela via intraperitoneal com 0,2ml de sangue, contendo 2,5 x 104 parasitas. Seis ratos não-inoculados foram utilizados como controles. Após inoculação, a parasitemia foi avaliada a cada 12h. Os grupos para análise foram estipulados de acordo com a média de tripanossomas em 10 campos homogêneos focados aleatoriamente, sendo: A, controle; B, animais que apresentaram um grau de parasitemia entre 1-10 tripanossomas/campo; C, ratos com 11-20 tripanossomas/campo; D, ratos com 21-30 tripanossomas/campo; E, ratos com 31-40 tripanossomas/campo; F, 41-50 tripanossomas/campo; e G, ratos com mais de 51 tripanossomas/campo. Quando os animais apresentaram o número de protozoários equivalente ao grupo, foram coletadas amostras de sangue para realização de hemograma e dosagem de ferro, e foi realizada citologia de medula óssea para avaliação da relação mielóide:eritróide. A análise estatística mostrou redução significativa das hemácias e do hematócrito a partir de 31 tripanossomas/campo (grupos E, F e G; PTrypanosoma evansi is a flagellate protozoan that causes a disease characterized by high parasitemia and acute anemia in various species. This study was aimed at evaluating and establishing a relationship between different parasitemia levels and eritropoyesis in Wistar rats (Rattus norvegicus experimentally infected by T. evansi. Forty two animals were used. In 36 animals parasites were inoculated by intraperitoneal blood injection of 0.2ml containing 2.5x104 parasites. Six non-inoculated animals

  5. Ocorrência de Trypanosoma evansi em eqüinos no município de Cruz Alta, RS, Brasil Occurrence of Trypanosoma evansi in equines in Cruz Alta, RS, Brazil

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    Régis Adriel Zanette

    2008-08-01

    Full Text Available O objetivo deste trabalho foi relatar a ocorrência de Trypanosoma evansi em eqüinos no município de Cruz Alta, Estado do Rio Grande do Sul, abordando aspectos epidemiológicos e sinais clínicos da infecção. A tripanosomose ocorreu em uma propriedade rural no município de Cruz Alta. Ao exame clínico, observou-se que quatro dos animais apresentavam marcha oscilante, com incoordenação dos membros posteriores. No entanto, eles estavam em bom estado nutricional, sem febre, bem hidratados e alimentavam-se normalmente. Foram coletadas amostras de sangue das éguas para hemograma, sendo identificado aumento das proteínas plasmáticas, leucocitose, eosinofilia e linfocitose em animais com sinais clínicos. No esfregaço sangüíneo periférico, observou-se a forma flagelada do T. evansi em três dos eqüinos.This study aimed at describing the occurrence of Trypanosoma evansi in equines from the city of Cruz Alta, RS, Brazil, relating epidemiological aspects and clinical signs of the infection. The tripanosomiasis occurred in a rural area of Cruz Alta, RS. Clinical signs presented by four animals were stiff and incoordinated gait of the pelvic members, although they were in good nutritional status, without fever, well-hydrated and eating normally. Blood samples were collected from the mares for hemogram. Increased levels of plasmatic proteins, leukocytosis, eosinophilia, and limphocytosis were observed in animals with clinical signs. Flagellated forms of T. evansi were observed in the blood smear of three animals.

  6. Aceturato de diminazeno e dipropionato de imidocarb no controle de infecção por Trypanosoma evansi em Rattus norvegicus infectados experimentalmente

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    Silva,Aleksandro Schafer da; Tochetto,Camila; Zanette,Régis Adriel; Pierezan,Felipe; Rissi,Daniel Ricardo; Santurio,Janio Morais; Monteiro,Silvia Gonzalez

    2008-01-01

    Este estudo teve como objetivo avaliar o efeito do aceturato de diminazeno e do dipropionato de imidocarb no controle da infecção por Trypanosoma evansi em ratos (Rattus norvegicus) infectados experimentalmente. Cinqüenta e quatro ratos machos foram inoculados via intraperitonial com 104 tripomastigotas de T. evansi/animal. Os ratos foram monitorados diariamente por meio de esfregaço sanguíneo periférico. No momento em que se observassem oito protozoários por campo microscópico de 1000x, era ...

  7. Aceturato de diminazeno e dipropionato de imidocarb no controle de infecção por Trypanosoma evansi em Rattus norvegicus infectados experimentalmente Diminazene aceturate and imidocarb dipropionate in the control of Trypanosoma evansi infection in Rattus norvegicus experimentally infected

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    Aleksandro Schafer da Silva

    2008-08-01

    Full Text Available Este estudo teve como objetivo avaliar o efeito do aceturato de diminazeno e do dipropionato de imidocarb no controle da infecção por Trypanosoma evansi em ratos (Rattus norvegicus infectados experimentalmente. Cinqüenta e quatro ratos machos foram inoculados via intraperitonial com 104 tripomastigotas de T. evansi/animal. Os ratos foram monitorados diariamente por meio de esfregaço sanguíneo periférico. No momento em que se observassem oito protozoários por campo microscópico de 1000x, era iniciado o tratamento com as drogas (dia zero. O estudo foi dividido em dois protocolos terapêuticos e os fármacos foram administrados via intramuscular. O primeiro protocolo foi aplicado nos grupos A, B, C e D e o segundo protocolo nos grupos E, F, G e H. O grupo controle foi identificado como grupo I, não medicados. No primeiro protocolo, os ratos receberam uma dose única dos fármacos no dia zero e sempre que se observasse T. evansi na circulação periférica. No segundo protocolo, os roedores receberam as mesmas doses, no entanto, por cinco dias consecutivos. No primeiro protocolo, os dois princípios ativos não apresentaram eficácia curativa, ocorrendo reincidência da parasitemia após alguns dias do tratamento. No segundo protocolo, o aceturato de diminazeno eliminou a forma tripomastigota da circulação e os ratos foram eutanasiados após 90 dias do início do tratamento. Os roedores tratados com dipropionato de imidocarb apresentaram recidiva da infecção após 30 dias. Na histopatologia não se observou alteração renal e hepática relacionada à doença ou aos medicamentos testados. Com base nos resultados, foi concluído que o aceturato de diminazeno, quando administrado por cinco dias consecutivos, é efetivo no tratamento da tripanossomose em ratos.The aim of this study was to evaluate the efficacy of diminazene aceturate and imidocarb dipropionate in the control of Trypanosoma evansi infection in rats (Rattus norvegicus

  8. Experimental Trypanosoma evansi infection in donkeys: hematological, biochemical and histopathological changes Infecção experimental em jumentos com Trypanosoma evansi: alterações hematológicas, bioquímicas e histopatológicas

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    F.A. Cadioli

    2006-10-01

    Full Text Available Five adult donkeys were experimentally infected with Brazilian strain of Trypanosoma evansi originally isolated from a naturally infected dog to study the hematological biochemical and histopathological alterations during the evolution of the disease. The course of the experimental infection was followed up to 145 days. Hematological analyses of the infected donkeys revealed a marked decline in hemoglobin, packed-cell volume, and erythrocyte count. Anemia was observed after successive peaks of parasitemia. Biochemical analyses showed increased levels of icterus index, serum globulins and decreased serum albumin and glucose values. All infected donkeys revealed enlargement of spleen and its white pulp, enlargement of mediastinal lymph nodes and lungs congestion. The main histopathological features consisted of meningoencephalitis. Demyelination in some areas of the cerebellum pediculus and neuropil vacuolization were observed. This study showed that donkeys infected with a Brazilian strain of T. evansi developed a chronic disease.Cinco jumentos, adultos foram infectados experimentalmente com cepa brasileira de Trypanosoma evansi, isolada de um cão naturalmente infectado, com o intuito de observar as alterações hematológicas, bioquímicas e histopatológicas durante a evolução da enfermidade. O curso da infecção experimental foi de 145 dias. Análise hematológica dos jumentos infectados revelou declínio nos valores de hemoglobina, hematócrito e contagem total de eritrócitos. Notou-se anemia após sucessivos picos de parasitemia. Análise bioquímica indicou aumento dos níveis de índice ictérico, globulinas séricas e diminuição dos valores séricos de albumina e glicose. Todos os jumentos infectados apresentaram aumento do baço e de sua polpa branca, aumento de linfonodos mediastínicos e congestão pulmonar. Meningoencefalite foi o principal achado histopatológico. Em algumas áreas do pedículo cerebelar foram observadas

  9. Trypanosoma evansi isolated from capybara (Hidrochaeris hidrochaeris

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    Karina Muñoz

    2001-10-01

    Full Text Available A study was conducted to determine the morphological and biometric characteristics of Trypanosoma isolated from 50 capybaras animals, raised in captivity in the Peruvian Amazon. Trypanosoma was found in 14 blood samples using the microhaematocrit, wide drop, and Giemsa-stain methods and T. evansi was identified through morphological details in all 14 positive samples (the subterminal kinetoplast, the developed undulating membrane, and a long free flagellum were used for the identification of the agent.

  10. EFICÁCIA DE TRÊS MEDICAMENTOS NO CONTROLE DA INFECÇÃO EXPERIMENTAL POR TRYPANOSOMA EVANSI EM RATOS (RATTUS NORVEGICUS) LINHAGEM WISTAR

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    Rovaina Laureano Doyle

    2006-01-01

    Este trabalho objetivou verificar os achados laboratoriais e histológicos da infecção experimental por Trypanosoma (Trypanozoon) evansi (Steel, 1885) Balbiani, 1888, em ratos (Rattus norvegicus) da linhagem Wistar, testando a eficácia de três medicamentos. Foram utilizados 40 ratos, divididos em quatro grupos de 10 cada, sendo cada grupo composto por 5 machos e cinco fêmeas, os quais foram tratados com três quimioterápicos distintos após a detecção de parasitemia superior a oit...

  11. Proteomics of Trypanosoma evansi infection in rodents.

    Science.gov (United States)

    Roy, Nainita; Nageshan, Rishi Kumar; Pallavi, Rani; Chakravarthy, Harshini; Chandran, Syama; Kumar, Rajender; Gupta, Ashok Kumar; Singh, Raj Kumar; Yadav, Suresh Chandra; Tatu, Utpal

    2010-03-22

    Trypanosoma evansi infections, commonly called 'surra', cause significant economic losses to livestock industry. While this infection is mainly restricted to large animals such as camels, donkeys and equines, recent reports indicate their ability to infect humans. There are no World Animal Health Organization (WAHO) prescribed diagnostic tests or vaccines available against this disease and the available drugs show significant toxicity. There is an urgent need to develop improved methods of diagnosis and control measures for this disease. Unlike its related human parasites T. brucei and T. cruzi whose genomes have been fully sequenced T. evansi genome sequence remains unavailable and very little efforts are being made to develop improved methods of prevention, diagnosis and treatment. With a view to identify potential diagnostic markers and drug targets we have studied the clinical proteome of T. evansi infection using mass spectrometry (MS). Using shot-gun proteomic approach involving nano-lc Quadrupole Time Of Flight (QTOF) mass spectrometry we have identified over 160 proteins expressed by T. evansi in mice infected with camel isolate. Homology driven searches for protein identification from MS/MS data led to most of the matches arising from related Trypanosoma species. Proteins identified belonged to various functional categories including metabolic enzymes; DNA metabolism; transcription; translation as well as cell-cell communication and signal transduction. TCA cycle enzymes were strikingly missing, possibly suggesting their low abundances. The clinical proteome revealed the presence of known and potential drug targets such as oligopeptidases, kinases, cysteine proteases and more. Previous proteomic studies on Trypanosomal infections, including human parasites T. brucei and T. cruzi, have been carried out from lab grown cultures. For T. evansi infection this is indeed the first ever proteomic study reported thus far. In addition to providing a glimpse into the

  12. Proteomics of Trypanosoma evansi infection in rodents.

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    Nainita Roy

    2010-03-01

    Full Text Available Trypanosoma evansi infections, commonly called 'surra', cause significant economic losses to livestock industry. While this infection is mainly restricted to large animals such as camels, donkeys and equines, recent reports indicate their ability to infect humans. There are no World Animal Health Organization (WAHO prescribed diagnostic tests or vaccines available against this disease and the available drugs show significant toxicity. There is an urgent need to develop improved methods of diagnosis and control measures for this disease. Unlike its related human parasites T. brucei and T. cruzi whose genomes have been fully sequenced T. evansi genome sequence remains unavailable and very little efforts are being made to develop improved methods of prevention, diagnosis and treatment. With a view to identify potential diagnostic markers and drug targets we have studied the clinical proteome of T. evansi infection using mass spectrometry (MS.Using shot-gun proteomic approach involving nano-lc Quadrupole Time Of Flight (QTOF mass spectrometry we have identified over 160 proteins expressed by T. evansi in mice infected with camel isolate. Homology driven searches for protein identification from MS/MS data led to most of the matches arising from related Trypanosoma species. Proteins identified belonged to various functional categories including metabolic enzymes; DNA metabolism; transcription; translation as well as cell-cell communication and signal transduction. TCA cycle enzymes were strikingly missing, possibly suggesting their low abundances. The clinical proteome revealed the presence of known and potential drug targets such as oligopeptidases, kinases, cysteine proteases and more.Previous proteomic studies on Trypanosomal infections, including human parasites T. brucei and T. cruzi, have been carried out from lab grown cultures. For T. evansi infection this is indeed the first ever proteomic study reported thus far. In addition to providing a

  13. Uveíte associada à infecção por Trypanosoma evansi em cães no município de Uruguaiana, RS, Brasil Uveíte associated to the infection by Trypanosoma evansi in dogs from Uruguaiana, RS, Brazil

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    Sérgio Santalucia

    2012-12-01

    Full Text Available Descrevem-se, neste trabalho, as alterações oculares de dois cães naturalmente infectados por Trypanosoma evansi. Os animais apresentaram, ao exame oftalmológico, teste lacrimal de Schirmer I normal, teste de fluoresceína negativo, quemose, hiperemia conjuntival, secreção mucopurulenta, miose, edema de córnea, pressão intraocular diminuída e efeito Tyndall positivo. No esfregaço sanguíneo, foram identificadas formas tripomastigotas, classificadas como pertencentes à espécie T. evansi. Pelos resultados aqui apresentados, concluímos quanto à necessidade de realização de avaliação oftalmológica completa em cães apresentando uveíte, incluindo exames parasitológicos específicos para hemoparasitas.This paper describes the ocular alterations of two dogs naturally infected by Trypanosoma evansi. The animals presented to an ophthalmologic examination, normal Schirmer tear test , negative fluorescein test, chemosis, conjunctival hyperemia, mucopurulent discharge, miosis, corneal edema, intraocular pressure decreased and positive Tyndall effect. In blood smears, trypomastigotes were identified, classified as belonging to the species T. evansi. By the results presented here, it was concluded that there is a necessity of performing a complete ophthalmological examination in dogs with uveitis, including parasitological examination specific to hemoparasites.

  14. Gastrointestinal parasites and Trypanosoma evansi in buffaloes

    International Nuclear Information System (INIS)

    Sani, R.A.; Chandrawathani, P.; Rosli, M.

    1990-01-01

    Gastrointestinal parasitism is common in buffalo calves. The effect of helminths on growth was studied by administration of an anthelmintic to buffalo calves following natural infections with gastrointestinal parasites. In studies conducted on calves belonging to an institute and a smallholder farmer, the treated calves showed improved weight gains. Serial parasitic examinations showed these animals had moderate to high faecal counts with Strongyloides, Toxocara vitulorum and Haemonchus eggs and Eimeria oocytes. In another study, there was no live weight advantage in treated over untreated calves. Few animals in this study had evidence of parasites and even those which were infested had low faecal egg counts. Hence, in general, helminths at certain levels of infection do affect the live weight gains of young buffalo calves. The prevalence of Trypanosoma evansi, as assessed parasitologically using the haematocrit centrifugation technique and mice inoculation, was 2.7 and 1%, respectively, in cattle and buffaloes. The serological prevalence using the enzyme linked immunosorbent assay was 35 and 2% for cattle and buffaloes, respectively. (author). 6 refs, 5 figs, 2 tabs

  15. Multiple evolutionary origins of Trypanosoma evansi in Kenya.

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    Christine M Kamidi

    2017-09-01

    Full Text Available Trypanosoma evansi is the parasite causing surra, a form of trypanosomiasis in camels and other livestock, and a serious economic burden in Kenya and many other parts of the world. Trypanosoma evansi transmission can be sustained mechanically by tabanid and Stomoxys biting flies, whereas the closely related African trypanosomes T. brucei brucei and T. b. rhodesiense require cyclical development in tsetse flies (genus Glossina for transmission. In this study, we investigated the evolutionary origins of T. evansi. We used 15 polymorphic microsatellites to quantify levels and patterns of genetic diversity among 41 T. evansi isolates and 66 isolates of T. b. brucei (n = 51 and T. b. rhodesiense (n = 15, including many from Kenya, a region where T. evansi may have evolved from T. brucei. We found that T. evansi strains belong to at least two distinct T. brucei genetic units and contain genetic diversity that is similar to that in T. brucei strains. Results indicated that the 41 T. evansi isolates originated from multiple T. brucei strains from different genetic backgrounds, implying independent origins of T. evansi from T. brucei strains. This surprising finding further suggested that the acquisition of the ability of T. evansi to be transmitted mechanically, and thus the ability to escape the obligate link with the African tsetse fly vector, has occurred repeatedly. These findings, if confirmed, have epidemiological implications, as T. brucei strains from different genetic backgrounds can become either causative agents of a dangerous, cosmopolitan livestock disease or of a lethal human disease, like for T. b. rhodesiense.

  16. Trypanosoma evansi: A clinical, parasitological and immunological ...

    African Journals Online (AJOL)

    Ibrahim Eldaghayes

    2012-08-13

    Aug 13, 2012 ... serum proteins in g/dl using a refractometer, haematocrit ... evansi IgG titer by indirect ELISA immunoassay, from both infected ... disease can be observed and the three characteristic stages, ... trypanosomosis caused by T. evansi have used horses .... The parasitemia as estimated by DME and MHCT for.

  17. Surtos de tripanossomíase por Trypanosoma evansi em eqüinos no Rio Grande do Sul: aspectos epidemiológicos, clínicos, hematológicos e patológicos Outbreaks of trypanosomiasis in horses by Trypanosoma evansi in the state of Rio Grande do Sul, Brazil: epidemiological, clinical, hematological, and pathological aspects

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    Aline Rodrigues

    2005-12-01

    Full Text Available Casos de tripanossomíase por Trypanosoma evansi foram diagnosticados em eqüinos no Rio Grande do Sul entre 2003 e 2004. Em uma propriedade (Propriedade A com 125 eqüinos, 52 morreram. A Propriedade A recebeu ao redor de 80 éguas de outras propriedades para cobertura. Dessas, 66 adoeceram e 56 morreram após voltarem para suas propriedades de origem. A doença clínica observada em 21 eqüinos caracterizava-se por emagrecimento (apesar de apetite voraz, letargia, incoordenação e instabilidade dos membros pélvicos, atrofia das grandes massas musculares dos membros pélvicos, fraqueza muscular e palidez das mucosas. Exemplares de T. evansi foram observados na corrente sangüínea de 4 eqüinos. Anemia normocítica normo-crômica, com hematócritos que variavam de 15-31%, e leuco-citose por linfocitose associada à presença de linfócitos atípicos foram observadas em vários eqüinos. Altos níveis de anticorpos contra T. evansi foram detectados em 6 eqüinos da Propriedade A. Oito eqüinos desenvolveram um quadro neurológico encefálico caracterizado por andar em círculos, ataxia, cegueira, hiperexcitabilidade, quedas, embotamento, déficits proprioceptivos e desvio da cabeça. Um eqüino desenvolveu "posição de cão sentado". Nas 13 necropsias, havia espleno-megalia, linfadenomegalia, hiperplasia linfóide no baço e linfo-nodo, atrofia das grandes massas musculares dos membros pélvicos, edema e malacia na substância branca e cinzenta do encéfalo. Histologicamente, uma panencefalite devastadora foi observada nos 7 casos e caracterizada por marcado edema, desmielinização, necrose e infiltrado perivascular de 6-10 camadas de células linfoplasmocitárias afetando tanto a substância branca quanto a cinzenta. Muitos plasmócitos do infiltrado inflamatório continham numerosos grânulos eosinofílicos no citoplasma (células de Mott. Lesões semelhantes foram observadas na medula espinhal do eqüino que desenvolveu "posição de c

  18. Molecular diagnosis of cattle trypanosomes in Venezuela: evidences of Trypanosoma evansi and Trypanosoma vivax infections.

    Science.gov (United States)

    Ramírez-Iglesias, J R; Eleizalde, M C; Reyna-Bello, A; Mendoza, M

    2017-06-01

    In South America Trypanosoma evansi has been determined by molecular methods in cattle from Bolivia, Brazil, Colombia and Peru, reason for which the presence of this parasite is not excluded in Venezuelan livestock. Therefore, the aim of this study was to perform parasitological and molecular diagnosis of cattle trypanosomosis in small livestock units from two regions in this country. The parasitological diagnosis was carried out by MHCT and the molecular by PCR using genus-specific ITS1 primers that differentiate T. vivax and T. evansi infections. 47 cattle were evaluated in the "Laguneta de la Montaña" sector, Miranda State, where 3 animals were diagnosed as positive (6.4 %) by MHCT and 14 (30 %) by PCR as Trypanosoma spp., out of which 9 animals resulted positive for T. vivax , 3 for T. evansi and 2 with double infections. Whilst in the "San Casimiro" sector, State of Aragua, out of the 38 cattle evaluated 7 animals were diagnosed as positive (18.4 %) by MHCT and 19 (50 %) by PCR, determining only the presence of T. evansi in this locality. The molecular diagnosis by PCR using ITS1 primers allowed T. evansi detection in cattle field populations, which suggests the possible role of these animals as reservoirs in the epidemiology of the disease caused by T. evansi in Venezuela.

  19. Humoral immune response of horses experimentally infected with Trypanosoma evansi/ Resposta imune humoral de eqüinos infectados experimentalmente com Trypanosoma evansi

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    Lúcia Padilha Cury Thomaz de Aquino

    2001-05-01

    Full Text Available Six adult horses were experimentally infected with Trypanosoma evansi (106 parasites. Three other adult horses served as negative control. Serum samples of the experimentally infected horses with T. evansi and non-infected controls horses were obtained before inoculation, and daily thereafter until 14 days post infection (DPI. After that time the serum samples were obtained weekly. Sera of the infected and non-infected control horses was tested by indirect fluorescent antibody test (IFAT and enzyme-linked immunosorbent assay (ELISA for the detection of antibodies against T. evansi. Both ELISA and IFAT detected trypanosomal antibodies shortly after infection and showed progressive increases in antibodies levels during early stages of infection. The responses started on the eighth and eleventh DPI. Maximum IFAT and ELISA values were reached after four weeks of infection and were maintained at this level until the end of the period of study.Seis eqüinos foram inoculados com 106 tripomastigota sangüícolas de Trypanosoma evansi. Três outros animais foram mantidos como testemunhas. Amostras de soro sangüíneo foram obtidas de todos os animais, antes da inoculação, e diariamente até o 14º dia pós inoculação (DPI; após este período uma vez por semana. Pesquisa de anticorpos anti- T. evansi, foram realizadas através da reação de imunofluorescência indireta (RIFI e do ensaio de imunoabsorção enzimática (ELISA. A resposta imune humoral, detectada através da RIFI e do ELISA, iniciou-se, em média, a partir do oitavo DPI, alcançando títulos máximos após quatro semanas de evolução, e os titulos de anticorpos anti- T. evansi mantiveram-se elevadas até o término das observações.

  20. Diminazene aceturate and imidocarb dipropionate in the control of Trypanosoma evansi infection in Rattus norvegicus experimentally infected

    OpenAIRE

    Silva, Aleksandro Schafer da; Tochetto, Camila; Zanette, Régis Adriel; Pierezan, Felipe; Rissi, Daniel Ricardo; Santurio, Janio Morais; Monteiro, Silvia Gonzalez

    2008-01-01

    Este estudo teve como objetivo avaliar o efeito do aceturato de diminazeno e do dipropionato de imidocarb no controle da infecção por Trypanosoma evansi em ratos (Rattus norvegicus) infectados experimentalmente. Cinqüenta e quatro ratos machos foram inoculados via intraperitonial com 104 tripomastigotas de T. evansi/animal. Os ratos foram monitorados diariamente por meio de esfregaço sanguíneo periférico. No momento em que se observassem oito protozoários por campo microscópico de 1000x, era ...

  1. Evaluation of In Vitro Activity of Essential Oils against Trypanosoma brucei brucei and Trypanosoma evansi

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    Nathan Habila

    2010-01-01

    Full Text Available Essential oils (EOs from Cymbopogon citratus (CC, Eucalyptus citriodora (EC, Eucalyptus camaldulensis (ED, and Citrus sinensis (CS were obtained by hydrodistillation process. The EOs were evaluated in vitro for activity against Trypanosoma brucei brucei (Tbb and Trypanosoma evansi (T. evansi. The EOs were found to possess antitrypanosomal activity in vitro in a dose-dependent pattern in a short period of time. The drop in number of parasite over time was achieved doses of 0.4 g/ml, 0.2 g/mL, and 0.1 g/mL for all the EOs. The concentration of 0.4 g/mL CC was more potent at 3 minutes and 2 minutes for Tbb and T. evansi, respectively. The GC-MS analysis of the EOs revealed presence of Cyclobutane (96.09% in CS, 6-octenal (77.11% in EC, Eucalyptol (75% in ED, and Citral (38.32% in CC among several other organic compounds. The results are discussed in relation to trypanosome chemotherapy.

  2. ACETURATO DE DIMINAZENO LIPOSSOMAL NO TRATAMENTO DA INFECÇÃO POR Trypanosoma evansi: TESTES in vitro E in vivo

    OpenAIRE

    Camila Belmonte Oliveira

    2014-01-01

    Este estudo teve como objetivo desenvolver e testar lipossomas de aceturato de diminazeno em testes in vitro e in vivo visando o controle de Trypanosoma evansi. O teste in vitro foi realizado em meio de cultura nas concentrações de 0,25, 0,5, 1, 2 e 3 μg/mL de aceturato de diminazeno convencional (C-DMZ) e lipossomal (L-DMZ). Para os testes in vivo foram utilizados 114 ratos (Rattus norvegicus) divididos em seis grupos (A, B, C, D, E e F) em dois experimentos, um para aval...

  3. Cholinesterase as inflammatory markers in a experimental infection by Trypanosoma evansi in rabbits

    Directory of Open Access Journals (Sweden)

    Márcio M. Costa

    2012-12-01

    Full Text Available The aim of this study is to evaluate the role of cholinesterases as an inflammatory marker in acute and chronic infection by Trypanosoma evansi in rabbits experimentally infected. Twelve adult female New Zealand rabbits were used and divided into two groups with 6 animals each: control group (rabbits 1-6 and infected group (rabbits 7-12. Infected group received intraperitoneally 0.5 mL of blood from a rat containing 108 parasites per animal. Blood samples used for cholinesterases evaluation were collected on days 0, 2, 7, 12, 27, 42, 57, 87, 102 and 118 days post-inoculation (PI. Increased activity (P0.05 was observed in the encephalic structures. The increased activities of AChE and BChE probably have a pro-inflammatory purpose, attempting to reduce the concentration of acetylcholine, a neurotransmitter which has an anti-inflammatory property. Therefore, cholinesterase may be inflammatory markers in infection with T. evansi in rabbits.O objetivo do presente estudo é avaliar o papel das colinesterases como marcadores inflamatórios nas fases aguda e crônica da infecção por T. evansi em coelhos infectados experimentalmente. Foram utilizados 12 coelhos adultos, fêmeas, da raça Nova Zelândia, divididos em dois grupos: um grupo controle, com seis animais (coelhos 1-6, e um grupo infectado, com seis animais (coelhos 7-12. Os animais pertencentes ao grupo infectados receberam, pela via intraperitoneal, 0,5 mL de sangue de rato contendo 108 tripanossomas por animal. Amostras do sangue utilizado para avaliação das colinesterases foram coletadas nos dias 0, 2, 7, 12, 27, 42, 57, 87, 102 e 118 pós-inoculação (PI. Aumento (P0,05 foi observada nas estruturas encefálicas. O aumento de atividade da AChE e BChE provavelmente tenha finalidade pró-inflamatória, a fim de reduzir as concentrações de acetilcolina, neurotransmissor que apresenta propriedade anti-inflamatória. Portanto, as colinesterases podem ser marcadores inflamatórios na infec

  4. Studies on the epidemiology of Trypanosoma evansi in buffaloes in Indonesia

    International Nuclear Information System (INIS)

    Payne, R.C.; Partoutomo, S.; Sukanto, I.P.

    1990-01-01

    Observations on buffaloes imported into Indonesia from Australia indicate that infections with Trypanosoma evansi were the possible causes of illness and death. In February 1986, 657 feral buffalo were imported from the Northern Territory, Australia, for distribution to smallholder farms in Central Java. Two locations were selected in which groups of buffaloes could regularly be examined and their response to infection with T. evansi monitored. In the first location, T. evansi was detected in an imported buffalo 2 months after distribution and Nagarol (Suramin; Bayer) was given to all the animals in the area as a prophylactic. In the second location, Trypamidium (isometamidium chloride; Specia) was used as a prophylactic when T. evansi was detected. Twelve of the 131 buffaloes under observation died in the first location and T. evansi was thought to be the cause of death in three animals. In the second location, 33 out of 45 buffaloes died; evidence of infection with T. evansi was detected in 25 animals. Serum samples were subjected to the enzyme linked immunosorbent assay to detect T. evansi antibodies. The results showed that imported buffaloes were seronegative on arrival, but seroconversion occurred at both locations. (author). 11 refs, 2 tabs

  5. ACETURATO DE DIMINAZENO ASSOCIADO AO SELENITO DE SÓDIO E A VITAMINA E: TESTES IN VITRO E EM RATOS EXPERIMENTALMENTE INFECTADOS COM Trypanosoma evansi

    OpenAIRE

    Alexandre Alberto Tonin

    2012-01-01

    O objetivo deste estudo foi avaliar a utilização de um tratamento padrão contra a infecção causada pelo T. evansi, baseado na utilização do aceturato de diminazeno associado ao selenito de sódio e a vitamina E. Os testes in vitro mostraram um efeito tripanocida relacionados ao tratamento com aceturato de diminazeno e selenito de sódio; contudo a vitamina E não gerou nenhum efeito nocivo sobre o tripanossomas. Experimentos in vivo utilizaram um total de 72 fêmeas adultas de rato...

  6. First report of surra (Trypanosoma evansi infection in a Tunisian dog

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    Rjeibi Mohamed Ridha

    2015-01-01

    Full Text Available Trypanosoma evansi, the agent of surra, is a salivarian trypanosome, originating from Africa. Surra is a major disease in camels, equines and dogs, in which it can often be fatal in the absence of treatment. Animals exhibit nonspecific clinical signs (anaemia, loss of weight and abortion. In the present survey, a blood sample was collected in Sousse (Central Tunisia from a dog that presented clinical signs of trypanosomiasis. Giemsa-stained blood smears and PCR were performed. ITS1 sequences from blood had 99.8 and 99.5% homology with published T. evansi sequences from cattle and camels, respectively. To our knowledge, this is the first report of T. evansi in a Tunisian dog.

  7. AVALIAÇÃO DA ATIVIDADE DE TRÊS COMPOSTOS DO ÓLEO DE MELALEUCA SOBRE O Trypanosoma evansi

    OpenAIRE

    Matheus Dellaméa Baldissera

    2016-01-01

    O objetivo deste estudo foi avaliar a atividade tripanocida do terpinen-4-ol, gama-(γ)-terpinen e alfa-(α)-terpinen contra o Trypanosoma evansi in vitro e in vivo. Os testes in vitro foram realizados em meio de cultura contendo T. evansi, utilizando-se três concentrações de cada composto (0.5, 1.0 e 2.0%) de forma individual e em associação. A contagem de tripomastigotas vivas foi realizada em câmara de Neubauer após 1, 3, 6 e 9 horas pós-incubação. A partir dos testes in vitro, foi...

  8. Molecular Confirmation of Trypanosoma evansi and Babesia bigemina in Cattle from Lower Egypt

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    Mahmoud M. Elhaig, Abdelfattah Selim, Mohamed M. Mahmoud and Eman K El-Gayar

    2016-11-01

    Full Text Available Trypanosomosis and babesiosis are economically important vector-borne diseases for animal health and productivity in developing countries. In Egypt, molecular epidemiological surveys on such diseases are scarce. In the present study, we examined 475 healthy and 25 clinically diagnosed cattle from three provinces in Lower Egypt, for Trypanosoma (T. and Babesia (B. infections using an ITS1 PCR assay that confirmed Trypanosoma species presence and an 18S rRNA assay that detected B. bigemina. Results confirmed Trypanosoma spp. and B. bigemina presence in 30.4% and 11% individuals, respectively, with eight animals (1.6% being co-infected with both hemoparasites. Subsequent type-specific PCRs revealed that all Trypanosoma PCR positive samples corresponded to T. evansi and that none of the animals harboured T. brucei gambiense or T. brucei rhodesiense. Nucleotide sequencing of the variable surface glycoprotein revealed the T. evansi cattle strain to be most closely related (99% nucleotide sequence identity to strains previously detected in dromedary camels in Egypt, while the 18S rRNA gene phylogeny confirmed the presence of a unique B. bigemina haplotype closely related to strains from Turkey and Brazil. Statistically significant differences in PCR prevalence were noted with respect to gender, clinical status and locality. These results confirm the presence of high numbers of carrier animals and signal the need for expanded surveillance and control efforts.

  9. Stomoxys calcitrans as possible vector of Trypanosoma evansi among camels in an affected area of the Canary Islands, Spain

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    Noé Francisco Rodríguez

    2014-07-01

    Full Text Available Introduction Trypanosoma evansi was first identified in the Canary Islands in 1997, and is still present in a small area of the Archipelago. To date, the disease has exclusively affected camel herds, and has not been detected in any other animal hosts. However potential vectors of Trypanosoma evansi must be identified. Methods One Nzi trap was placed on a camel farm located in the infected area for a period of one year. Results Two thousand five hundred and five insects were trapped, of which Stomoxys calcitrans was the sole hematophagous vector captured. Conclusions Stomoxys calcitrans could be exclusively responsible for the transmission of Trypanosoma evansi among camels in the surveyed area, as other species do not seem to be infected by S. calcitrans in the presence of camels.

  10. The capybara (Hydrochoerus hydrochaeris) as a reservoir host for Trypanosoma evansi.

    Science.gov (United States)

    Morales, G A; Wells, E A; Angel, D

    1976-10-01

    Discovery of two ill horses and three dogs naturally infected with Trypanosoma evansi near an experimental station in the Eastern Plains of Colombia led to a search for reservoir hosts of the parasite. Infection was detected in 8/33 healthy capybaras (Hydrochoerus hydrochaeris), none of the remaining 14 horses, and none of 32 Zebu cattle (Bos indicus), 18 paca (Cuniculus paca) and 20 spiny rats (Proechimys sp.). Contrary to common opinion, the results indicated a carrier state in the capybara. Diagnosis was based on morphology, behaviour in albino rats, and pathogenicity and host range in domestic animals.

  11. Surra Sero K-SeT, a new immunochromatographic test for serodiagnosis of Trypanosoma evansi infection in domestic animals.

    Science.gov (United States)

    Birhanu, Hadush; Rogé, Stijn; Simon, Thomas; Baelmans, Rudy; Gebrehiwot, Tadesse; Goddeeris, Bruno Maria; Büscher, Philippe

    2015-07-30

    Trypanosoma evansi, the causative agent of surra, infects different domestic and wild animals and has a wide geographical distribution. It is mechanically transmitted mainly by haematophagous flies. Parasitological techniques are commonly used for the diagnosis of surra but have limited sensitivity. Therefore, serodiagnosis based on the detection of T. evansi specific antibodies is recommended by the World Organisation for Animal Health (OIE). Recently, we developed a new antibody detection test for the serodiagnosis of T. evansi infection, the Surra Sero K-SeT. Surra Sero K-SeT is an immunochromatographic test (ICT) that makes use of recombinant variant surface glycoprotein rVSG RoTat 1.2, produced in the yeast Pichia pastoris. In this study, we compared the diagnostic accuracy of the Surra Sero K-SeT and the Card Agglutination Test for T. evansi Trypanosomososis (CATT/T. evansi) with immune trypanolysis (TL) as reference test on a total of 806 sera from camels, water buffaloes, horses, bovines, sheep, dogs and alpacas. Test agreement was highest between Surra Sero K-SeT and TL (κ=0.91, 95% CI 0.841-0.979) and somewhat lower between CATT/T. evansi and TL (κ=0.85, 95% CI 0.785-0.922) and Surra Sero K-SeT and CATT/T. evansi (κ=0.81, 95% CI 0.742-0.878). The Surra Sero K-SeT displayed a somewhat lower overall specificity than CATT/T. evansi (94.8% versus 98.3%, χ(2)=13.37, p<0.001) but a considerably higher sensitivity (98.1% versus 84.4%, χ(2)=33.39, p<0.001). We conclude that the Surra Sero K-SeT may become an alternative for the CATT/T. evansi for sensitive detection of antibodies against T. evansi in domestic animals. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Using of essential oils in the treatment of mice infected with Trypanosoma evansi

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    Matheus D. Baldissera

    2014-06-01

    Full Text Available Objective. This study aimed to test the effectiveness of copaiba, andiroba and aroeira essential oils for controlling trypanosomosis by Trypanosoma evansi with mice as experimental model. Materials and methods. Sixty-six mice were divided into eleven groups (A to L with six animals each. Group A was the unique composed by healthy and uninfected animals (negative control. Animals in groups B to L were inoculated with 0.1 mL of blood containing 2.7 x 106 trypanosomes. Group B was used as a positive control without treatment. In experiment were tested copaiba (C, D and E, andiroba (F, G and H and aroeira (I, J and L oils at doses of 0.6, 0.8 and 1.0 mL kg-1 to infected mice (T. evansi. Results. These protocols did not provide curative efficacy; however, the mice treated with highest dose of copaiba showed a significant increase in the longevity when compared others groups. Conclusions. Previously in our studies, these essential oils have shown trypanocidal activity in vitro, but when they were tested in vivo in mice infected with T. evansi, this trypanocidal activity, or the curative effect was not found, being only able to prolong the lifespan of the animals treated with copaiba oil.

  13. Cytokine gene expression and pathology in mice experimentally infected with different isolates of Trypanosoma evansi.

    Science.gov (United States)

    Krishnamoorthy, P; Sengupta, P P; Das, Sangita; Ligi, M; Shome, B R; Rahman, H

    2016-11-01

    Aim of the present study was to assess the cytokine gene expression in liver, kidney and spleen and histopathological changes in mice infected with buffalo and dog isolates of Trypanosoma evansi. Forty-four Swiss albino mice was divided into eleven groups of four mice each and injected subcutaneously with 1 × 10 5 trypanosomes of buffalo and dog isolate to twenty mice each, four mice served as control. Mice were examined for clinical signs, blood smear for trypanosome counts. Blood for PCR, liver, kidney, spleen, heart, lung, testis and abdominal muscle for histopathology and liver, kidney, spleen for cytokine gene expression studies, were collected. Mice showed dullness, lethargy, hunched back, sluggish movements on D4 and D5 in buffalo and dog isolate, respectively. Parasite count in blood varied between the two isolates of T. evansi. By PCR, trypanosome DNA was detected on D1 and D2 for buffalo and dog isolate, respectively. Splenomegaly was observed in mice infected with buffalo isolate but not with dog isolate. Histopathological changes were observed in liver, kidney, spleen and heart of mice but no changes in testis and abdominal muscles. Blood vessels of liver, heart, lung showed presence of trypanosomes in mice infected with buffalo isolate but not for dog isolate. Cytokine gene expression of IL-2, IL-4, IL-6, IL-12, TNF-α and IFN-γ increased in liver, kidney and spleen in both these isolates. However, the buffalo isolate exhibited pronounced increase in cytokine gene expression when compare to dog isolate of T. evansi. Anti-inflammatory cytokine gene IL-10 showed 50-60 and 10-20 folds increment in buffalo and dog isolates, respectively. This is the first report of IL-4, IL-6, IL-10 and IL-12 cytokine changes in mice infected with T. evansi. A variation in pathogenicity between buffalo and dog isolates was recorded indicating buffalo isolate of T. evansi remained more pathogenic in mice. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Effects of experimental Trypanosoma evansi infection on pregnancy in Yankasa ewes.

    Science.gov (United States)

    Adeyeye, A A; Ate, I U; Lawal, A I; Adamu, S

    2016-03-15

    Twenty pregnant Yankasa ewes were assigned to three groups to determine the effect of Trypanosoma evansi infection on pregnancy. Groups A and B comprising seven ewes each were infected with approximately 1.0 × 10(6) cells of T evansi per ewe through venepuncture at the second and third trimesters of pregnancy, respectively. Group C comprising six ewes served as uninfected control. There was slight pyrexia in the infected groups (groups A and B) but was absent in group C. The mean body weight, glucose concentration, and packed cell volume of ewes in group A were not significantly different from those in group C throughout the study. There was also no significant difference in mean glucose concentration between groups B and C. However, in group B, mean body weight was significantly (P ewes in group A was significantly (P ewes in group B decreased significantly (P ewes in the infected groups (groups A and B) compared with those in group C. However, there were significant (P ewes in group B compared with ewes in groups A and C. Mice inoculation with blood from infected ewes postpartum was parasitemic 18 to 25 days pi, for ewes in group B, whereas none of the mice in groups A and C were parasitemic. Lambs born from the infected groups (groups A and B) were also aparasitemic for 40 days postpartum. It was therefore concluded that the T evansi isolate used caused mild trypanosomosis when infected at third trimester, whereas ewes infected at second trimester were resistant. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. African trypanosomiasis with special reference to Egyptian Trypanosoma evansi: is it a neglected zoonosis?

    Science.gov (United States)

    El-Bahnasawy, Mamdouh M M; Khater, Mai Kh A; Morsy, Tosson A

    2014-12-01

    Trypanosomes (including humans) are blood and sometimes tissue parasites of the order Kinetoplastida, family Trypanosomatidae, genus Trypanosoma, principally transmitted by biting insects where most of them undergo a biological cycle. They are divided into Stercoraria with the posterior station inoculation, including T. cruzi, both an extra- and intracellular parasite that causes Chagas disease, a major human disease affecting 15 million people and threatening 100 million people in Latin America, and the Salivaria with the anterior station inoculation, mainly African livestock pathogenic trypanosomes, including the agents of sleeping sickness, a major human disease affecting around half a million people and threatening 60 million people in Africa. Now, T. evansi was reported in man is it required to investigate its zoonotic potential?

  16. Trypanosoma evansi

    African Journals Online (AJOL)

    Parasitaemia in the untreated control and the treated rats were monitored using Haematocrit Centrifuge Technique. (HCT) twice weekly. Two rats from each group were sacrificed at 45 dpi; visceral ... Protozoology laboratory of the Department of. Veterinary Parasitology and Entomology, Ahmadu Bello. University, Zaria for ...

  17. Epidemiology of camel trypanosomosis due to Trypanosoma evansi in Mauritania and its control strategies for sustainable livestock production

    Energy Technology Data Exchange (ETDEWEB)

    Dia Mamadou Lamine [CNERV, Nouakchott (Mauritania)], E-mail: mldsb@hotmail.com

    2009-07-01

    Camel trypanosomiasis due to Trypanosoma evansi is mechanically transmitted by hematophagious diptera such as Tabanidae, Stomoxyinae, and Hippoboscidae. In its acute form, the disease results in a generalized weakness. The animal lies down as of the least effort; milk production falls with the abortion of females. At times, the animal dies after a prolonged decubitus. However, in 80% cases, the disease is observed in its chronic form, which is characterized by considerable economic losses resulting from abortions, reduction of milk production, loss weight, and cachexia. Due to its extremely dry conditions Mauritania remains a favourable environment for camels as preferred livestock species of considerable economic importance. The animals are kept by shepherds who are very mobile in the field in search of good pastures and water points. Unfortunately, this pastoral system is reported to expose dromedaries to numerous pathologic conditions, especially camel trypanosomiasis due to T. evansi. Our investigations from 1993 to 1997 showed that T. evansi is present in the dromedaries in Mauritania. According the haematocrit centrifuge technique the parasite prevalence rate ranged from 1.1 to 13.6 % while seroprevalence varied from 13% to 36.7% according to the CATT test. In the Trarza region, as consequence of a good rainy season we more recently observed an abundance of tabanids and stomoxes hence a favourable ecology of T. evansi vectors, and subsequently an outbreak of camel trypanosomosis. Prevalence rate was 17.6% using buffy coat examination and 58.8% with the CATT. In many herds, numerous abortions were recorded and all breeders registered very important milk production losses. In order to limit the infections due to T. evansi, two control strategies for camel husbandry could be practiced in the Trarza region. The first is 'northern strategy' with the potential of lowering pastures availability and usage. However, it has the advantage of avoiding the direct and

  18. Profil Protein Trypanosoma evansi dari Daerah Geografis Berbeda di Indonesia Tahun 2012-2014 dengan Sodium Dodecil Sulphate Polyacrylamide Gel Electrophoresis (TRYPANOSOMA EVANSI PROTEIN PROFILE OF DIFFERENT GEOGRAPHICAL AREAS ORIGIN IN INDONESIA

    Directory of Open Access Journals (Sweden)

    Fitrine Ekawasti

    2018-01-01

    Full Text Available Surra outbreak in 2012 has led to more than 1,700 animals have died in the province of East Nusa Tenggara (NTT Indonesia. Surra case sporadically continues throughout the year in various areas, especially Kalimantan, Banten as well as other areas. Some reports reveal differences in protein profiles among multiple isolates of T. evansi. Therefore the purpose of this research were to find out the protein profile of each isolate T. evansi in Indonesia and the possible biological differences among them. Eleven isolates originating from the province of East Nusa Tenggara, South Kalimantan and Central Kalimantan, Banten, Lampung and Bengkulu has been isolated and purified Using DEAE. Trypanosoma isolate were frezeethawing repeatedly to obtain soluble protein. Furthermore, soluble protein is treated with heating or without heating and then each was run on SDS PAGE with Coomassie Blue staining. The protein profiles of all isolates were compared each other. The results showed that eleven isolates of T. evansi in Indonesia has a very diverse protein profile. Then for the purposes of development of diagnostic kit can be used whole lysate cell (WCL as stock antigen in serological test process.

  19. PCR-Based Detection of Trypanosoma evansi Infection in Semi-Captive Asiatic Black Bears (Ursus thibetanus

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    Maliha Shahid, Safia Janjua*, Fakhar-i-Abbas and Jan Schmidt Burbach1

    2013-11-01

    Full Text Available Clinical signs, viz lethargy, increased heart rate and reduced appetite, making trypanosomiasis a possible differential diagnosis, were found in five out of twenty semi-captive Asiatic black bears (Ursus thibetanus in a sanctuary, located in Kund, District Sawabi, KPK, Pakistan. Microscopic examination of blood samples of bears expressing clinical signs and symptoms revealed the presence of haemoflagellates, which was found to be trypanosomes. Subsequently, the PCR technique was exploited to screen for the presence of trypanosomal species in all bears’ blood samples. Blood samples from 20 individual bears were screened using three sets of primers specific to Trypanosoma evansi species. Three primer pairs used are equally effective in successful detection of the parasite. Two out of five, diseased bears died prior to any trypanosoma specific medication while the rest were given an administered dose of Melarsomine (Immiticide. The treated bears survived and were assured to be aparasitemic on post-treatment examination after six weeks.

  20. Trypanosoma evansi and Surra: A Review and Perspectives on Origin, History, Distribution, Taxonomy, Morphology, Hosts, and Pathogenic Effects

    Directory of Open Access Journals (Sweden)

    Marc Desquesnes

    2013-01-01

    Full Text Available Trypanosoma evansi, the agent of “surra,” is a salivarian trypanosome, originating from Africa. It is thought to derive from Trypanosoma brucei by deletion of the maxicircle kinetoplastic DNA (genetic material required for cyclical development in tsetse flies. It is mostly mechanically transmitted by tabanids and stomoxes, initially to camels, in sub-Saharan area. The disease spread from North Africa towards the Middle East, Turkey, India, up to 53° North in Russia, across all South-East Asia, down to Indonesia and the Philippines, and it was also introduced by the conquistadores into Latin America. It can affect a very large range of domestic and wild hosts including camelids, equines, cattle, buffaloes, sheep, goats, pigs, dogs and other carnivores, deer, gazelles, and elephants. It found a new large range of wild and domestic hosts in Latin America, including reservoirs (capybaras and biological vectors (vampire bats. Surra is a major disease in camels, equines, and dogs, in which it can often be fatal in the absence of treatment, and exhibits nonspecific clinical signs (anaemia, loss of weight, abortion, and death, which are variable from one host and one place to another; however, its immunosuppressive effects interfering with intercurrent diseases or vaccination campaigns might be its most significant and questionable aspect.

  1. Effect of zinc supplementation on E-ADA activity, seric zinc, and cytokines levels of Trypanosoma evansi infected Wistar rats.

    Science.gov (United States)

    Bottari, Nathieli B; Baldissera, Matheus D; Oliveira, Camila B; Duarte, Thiago; Duarte, Marta M M F; Leal, Marta L R; Thomé, Gustavo R; Zanini, Daniela; Schetinger, Maria Rosa C; Nunes, Matheus A G; Dressler, Valderi L; Monteiro, Silvia G; Tonin, Alexandre A; Da Silva, Aleksandro S

    2014-09-01

    The aim of this study was to evaluate the effect of zinc supplementation on the ecto-adenosine deaminase activity (E-ADA), zinc seric levels and cytokines (TNF-α, IL-1, IL-6, and IL -10) on rats experimentally infected by Trypanosoma evansi. Four groups with 10 rats each were used as negative controls (groups A and B), while the animals from the groups C and D were infected intraperitoneally with 0.1 mL of cryopreserved blood containing 1.4 × 10(4) of trypanosomes. Animals of groups B and D received two doses of Zinc (Zn) at 5 mg kg(-1), subcutaneously, on the 2nd and 7th day post-infection (PI). Blood samples were collected on days 5 (n = 5) and 15 PI (n = 5). Zn supplementation was able to increase the rat's longevity and to reduce their parasitemia. It was observed that seric Zn levels were increased on infected animals under Zn supplementation. Animals that were infected and supplemented with Zn showed changes in E-ADA activity and in cytokine levels (P ADA activity, as well as reduced the concentration of cytokines. Infected animals from groups C and D showed increased levels of cytokines. Finally, we observed that Zn supplementation led to a modulation on cytokine's level in rats infected by T. evansi, as well as in E-ADA activity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Susceptibility of Mice to Trypanosoma evansi Treated with Human Plasma Containing Different Concentrations of Apolipoprotein L-1

    Science.gov (United States)

    Fanfa, Vinicius R.; Otto, Mateus A.; Gressler, Lucas T.; Tavares, Kaio C.S.; Lazzarotto, Cícera R.; Tonin, Alexandre A.; Miletti, Luiz C.; Duarte, Marta M.M.F.; Monteiro, Silvia G.

    2011-01-01

    The aim of this study was to test the susceptibility of mice to Trypanosoma evansi treated with human plasma containing different concentrations of apolipoprotein L-1 (APOL1). For this experiment, a strain of T. evansi and human plasma (plasmas 1, 2, and 3) from 3 adult males clinically healthy were used. In vivo test used 50 mice divided in 5 groups (A to E) with 10 animals in each group. Animals of groups B to E were infected, and then treated with 0.2 ml of human plasma in the following outline: negative control (A), positive control (B), treatment with plasma 1 (C), treatment with plasma 2 (D), and treatment with plasma 3 (E). Mice treated with human plasma showed an increase in longevity of 40.9±0.3 (C), 20±9.0 (D) and 35.6±9.3 (E) days compared to the control group (B) which was 4.3±0.5 days. The number of surviving mice and free of the parasite (blood smear and PCR negative) at the end of the experiment was 90%, 0%, and 60% for groups C, D, and E, respectively. The quantification of APOL1 was performed due to the large difference in the treatments that differed in the source plasma. In plasmas 1, 2, and 3 was detected the concentration of 194, 99, and 115 mg/dl of APOL1, respectively. However, we believe that this difference in the treatment efficiency is related to the level of APOL1 in plasmas. PMID:22355213

  3. Variant surface glycoproteins from Venezuelan trypanosome isolates are recognized by sera from animals infected with either Trypanosoma evansi or Trypanosoma vivax.

    Science.gov (United States)

    Camargo, Rocío; Izquier, Adriana; Uzcanga, Graciela L; Perrone, Trina; Acosta-Serrano, Alvaro; Carrasquel, Liomary; Arias, Laura P; Escalona, José L; Cardozo, Vanessa; Bubis, José

    2015-01-15

    Salivarian trypanosomes sequentially express only one variant surface glycoprotein (VSG) on their cell surface from a large repertoire of VSG genes. Seven cryopreserved animal trypanosome isolates known as TeAp-ElFrio01, TEVA1 (or TeAp-N/D1), TeGu-N/D1, TeAp-Mantecal01, TeGu-TerecayTrino, TeGu-Terecay03 and TeGu-Terecay323, which had been isolated from different hosts identified in several geographical areas of Venezuela were expanded using adult albino rats. Soluble forms of predominant VSGs expressed during the early infection stages were purified and corresponded to concanavalin A-binding proteins with molecular masses of 48-67 kDa by sodium dodecyl sulfate-polyacrylamide gel electropohoresis, and pI values between 6.1 and 7.5. The biochemical characterization of all purified soluble VSGs revealed that they were dimers in their native form and represented different gene products. Sequencing of some of these proteins yielded peptides homologous to VSGs from Trypanosoma (Trypanozoon) brucei and Trypanosoma (Trypanozoon) evansi and established that they most likely are mosaics generated by homologous recombination. Western blot analysis showed that all purified VSGs were cross-reacting antigens that were recognized by sera from animals infected with either T. evansi or Trypanosoma (Dutonella) vivax. The VSG glycosyl-phosphatidylinositol cross-reacting determinant epitope was only partially responsible for the cross-reactivity of the purified proteins, and antibodies appeared to recognize cross-reacting conformational epitopes from the various soluble VSGs. ELISA experiments were performed using infected bovine sera collected from cattle in a Venezuelan trypanosome-endemic area. In particular, soluble VSGs from two trypanosome isolates, TeGu-N/D1 and TeGu-TeracayTrino, were recognized by 93.38% and 73.55% of naturally T. vivax-infected bovine sera, respectively. However, approximately 70% of the sera samples did not recognize all seven purified proteins. Hence, the

  4. Making antigen of trypanosoma evansi and its examination by catt (card agglutination test) method

    International Nuclear Information System (INIS)

    Arifin, M; Irtisam; Estikoma Dyah; Yulia Ernawati; Boky, J.T

    1998-01-01

    An experiment was carried out for making antigen (Ag) of T. evansi by using experimental animals rats and guinea pigs for for developing parasites, and in cattle for making immune serum and normal serum. The parasites were irradiated by gamma rays ( 60 Co) at a dose of 300 Gy. The determination of antigen was done by using Card Agglutination Test (CATT) to the field samples serum of cattle. The results obtained showed that antigen was good enough potently and stable at minus 70 0 C storage during five months. (author)

  5. The Effect Of Inoculation Dose Of trypanosoma Evansi On Blood Value In Animal Hosts f Mice

    International Nuclear Information System (INIS)

    Arifin, M.

    2002-01-01

    An experiment was carried out to obtain the information and its relation between a number of parasites and pathogenity in mice. The pathogenity of T. evansi was depend on the exchange of blood value of infected mice. The parasites was irradiated by gamma rays 6 O C o with the dose of and 300 Gy. The dose of inoculation were 1 x 10 5 , 5 x 10 5 and 1 x 10 6 parasites per mice. The results obtained showed that a number of parasites were inoculated caused the drop of blood value of mice. The number of parasites and irradiation were also significant effect to the blood value (P<0.01)

  6. Efficacy Study of Novel Diamidine Compounds in a Trypanosoma evansi Goat Model

    Science.gov (United States)

    Gillingwater, Kirsten; Gutierrez, Carlos; Bridges, Arlene; Wu, Huali; Deborggraeve, Stijn; Ali Ekangu, Rosine; Kumar, Arvind; Ismail, Mohamed; Boykin, David; Brun, Reto

    2011-01-01

    Three diamidines (DB 75, DB 867 and DB 1192) were selected and their ability to cure T. evansi experimentally infected goats was investigated. A toxicity assessment and pharmacokinetic analysis of these compounds were additionally carried out. Goats demonstrated no signs of acute toxicity, when treated with four doses of 1 mg/kg/day (total dose 4 mg/kg). Complete curative efficacy of experimentally infected goats was seen in the positive control group treated with diminazene at 5 mg/kg and in the DB 75 and DB 867 groups treated at 2.5 mg/kg. Drug treatment was administered once every second day for a total of seven days. Complete cure was also seen in the group of goats treated with DB 75 at 1.25 mg/kg. DB 1192 was incapable of curing goats at either four-times 2.5 mg/kg or 1.25 mg/kg. Pharmacokinetic analysis clearly demonstrated that the treatment failures of DB 1192 were due to sub-therapeutic compound levels in goat plasma, whilst compound levels for DB 75 and DB 867 remained well within the therapeutic window. In conclusion, two diamidine compounds (DB 75 and DB 867) presented comparable efficacy at lower doses than the standard drug diminazene and could be considered as potential clinical candidates against T. evansi infection. PMID:21698106

  7. A Possible Role for Rusa Deer (Cervus timorensis russa and Wild Pigs in Spread of Trypanosoma evansi from Indonesia to Papua New Guinea

    Directory of Open Access Journals (Sweden)

    SA Reid

    1999-03-01

    Full Text Available Movement of transmigrants and livestock from western Indonesia to southeastern areas of Irian Jaya near the border with Papua New Guinea may pose a risk of introducing Trypanosoma evansi into Papua New Guinea via feral Rusa deer (Cervus timorensis russa and wild pigs which inhabit these areas in large numbers. Pilot experimental studies were conducted to observe infection in pigs and Rusa deer with a strain of T. evansi isolated in Indonesia. Parasitaemia and signs of clinical disease were monitored each second day for 120 days. Trypanosomes were observed in haematocrit tubes at the plasma-buffy coat interface of jugular blood of deer and pigs on 86% and 37% of sampling occasions respectively. Parasitaemia was at a high level in deer for 35% of the time but for only 11.5% of the time in pigs. Results indicate that both Rusa deer and pigs have a high tolerance for infection with T. evansi. The deer suffered mild anaemia evidenced by a 25% reduction in packed cell volume (PCV 14 days after infection which coincided with the initial peak in parasitaemia. However, PCV had returned to pre infection values by the end of the experiment. The pigs showed no change in PCV. There were no visual indications of disease in either species and appetite was not noticeably affected. It was concluded that both Rusa deer and pigs were capable reservoir hosts for T. evansi but that Rusa deer, with their more persistent higher levels of parasitaemia, have more potential to spread T. evansi into Papua New Guinea from West Irian than pigs.

  8. Futile import of tRNAs and proteins into the mitochondrion of Trypanosoma brucei evansi

    Czech Academy of Sciences Publication Activity Database

    Paris, Zdeněk; Hashimi, Hassan; Lun, Sijia; Alfonzo, J. D.; Lukeš, Julius

    2011-01-01

    Roč. 176, č. 2 (2011), 116-120 ISSN 0166-6851 R&D Projects: GA ČR GA204/09/1667; GA MŠk LC07032 Institutional research plan: CEZ:AV0Z60220518 Keywords : Trypanosoma * tRNA * Protein import * Mitochondrion * Kinetoplast Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.551, year: 2011

  9. Estimating the impact of Trypanosoma evansi infection (surra) on buffalo population dynamics in southern Philippines using data from cross-sectional surveys.

    Science.gov (United States)

    Dargantes, A P; Mercado, R T; Dobson, R J; Reid, S A

    2009-08-01

    Despite the widespread problem with surra (Trypanosoma evansi) in livestock, there are no published studies on its impact on host populations, probably because of the large financial and time cost involved in performing longitudinal studies. During 2002-6, a cross-sectional survey for T. evansi infection involving 1732 buffaloes from 71 villages in southern Philippines was carried out. Other livestock animals (horses, cattle and goats) in every surveyed village were also tested for infection with T. evansi but domestic buffaloes were the primary survey target. Seroprevalence ranged from 6% to 21% and 13% to 100% for buffaloes in low and high risk areas, respectively. Key demographic parameters were estimated from the age structured distributions of the sampled buffalo population for each sex. All areas were dominated by females (69%) and the annual calving rate for areas of 100% and low seroprevalence was 15% and 47%, respectively. Males were removed at a relatively high annual rate of 27% in all areas. In the main reproductive years (4-10) female removal/mortality was financial losses due to reduced fertility, high mortality/removal rate and the necessity to import replacement buffaloes.

  10. antigen from irradiated Trypanosoma evansi and its correlation with antibody forming

    International Nuclear Information System (INIS)

    Sadi, Suharni; Arifin, Muchson

    1998-01-01

    In this research parasites of T. evansi was weakened by gamma irradiation dose of 300 Gy. This antigen being before being used was coupled/bounded with a carrier (Freund's adjuvant). West star rats of 3 months old were as used as treated animal. These animal were divided into 4 groups contained 5 rats. Group I (Control) was untreated animals, Group II (radiation) the animals were irradiated with a low dose 0.5 Gy. Group III Immunization) the animals were immunized with irradiated antigen, and Group IV (Immunization and radiation) the animal were immunized and then irradiated with a low dose of 0.5 Gy. Immunization were done by intraperitoneal route with irradiated antigen (0.5-1ml). These results were as follows : the polyclonal antibody forming of Group I (control), Group II (Radiation), Group III (Immunization), and Group IV (Immunization and radiation) were 6.34; 5.96; and 5.88 mg/ml, respectively. Group III (Immunization) Yielded polyclonal antibody a little higher than the other treated animals. Even though the antigen was coupled with a carrier, it seemed that it did not influence the parasites variant antigenic types (VTA). (author)

  11. Control of Trypanosoma evansi in buffalo in Indonesia: Identification of infected animals by Ag- and Ab-ELISA tests and treatment with diminazene aceturate

    International Nuclear Information System (INIS)

    Luckins, A.G.

    2000-01-01

    In order to control effectively infections with Trypanosoma evansi it is necessary to identify all infected individuals, including not only animals with patent infections but also those with non-patent infections. In order to provide a reliable means of diagnosing infected individuals, a combination of Ab-ELISA, Ag-ELISA and parasitological tests were used to identify for treatment groups of buffalo from Central Java, Indonesia in an area in which trypanosomosis caused by T. evansi is endemic. The animals were divided into four groups, Group A comprised animals positive by both Ab- and Ag-ELISA and/or parasitological examination. Group B consisted of animals positive by Ag-ELISA and Group C by Ab-ELISA only. Group D was a control group of animals that were negative by both serological and parasitological tests. All of Group A were treated with diminazene aceturate and the prevalence and incidence of infection in the four groups determined over approximately 12 months. The prevalence of infection declined in Group A declined from 100% to <25% in four months and remained at this low level until the end of the study. In the other groups, the serological prevalence increased up to 50%, although in Group D, the initially uninfected group, the increase was lower. Although treatment was effective in reducing the prevalence of infection, the cumulative incidence in the four groups was found to be similar. (author)

  12. Astrocytic and microglial response and histopathological changes in the brain of horses with experimental chronic Trypanosoma evansi infection Resposta astrocítica e microglial e alterações histopatológicas no sistema nervoso central de eqüinos infectados cronicamente com Trypanosoma evansi

    Directory of Open Access Journals (Sweden)

    Karen Regina Lemos

    2008-08-01

    isolada de um cão infectado naturalmente. Todos os eqüinos inoculados foram observados até o aparecimento dos sintomas neurológicos, caracterizados por incoordenação motora dos membros pélvicos, o qual ocorreu entre 67 e 124 dias após a inoculação (DPI. Os animais do grupo controle não apresentaram sinais clínicos e foram observados até o 125º DPI. Para este propósito, foram utilizados os métodos histoquímicos (HE e imunoistoquímicos do complexo avidina-biotina peroxidase (ABC. A lesão no sistema nervoso central (SNC dos eqüinos infectados com T. evansi foi caracterizada como meningoencefalomielite não supurativa. A gravidade das lesões variou em diferentes segmentos do SNC, refletindo distribuição irregular das alterações vasculares. Infiltrado perivascular e meníngeo foi associado a gliose anisomórfica e microgliose reativa. A intensidade da resposta astrocítica no SNC dos equinos infectados com T. evansi caracteriza a importância da performance destas células nas tripanossomíases. A gliose observada nos animais deste experimento sugerem a habilidade destas células como mediadoras da resposta imune. T. evansi não foi identificado no parênquima do SNC.

  13. EXPERIMENTAL INFECTION BY Trypanosoma vivax IN GOATS INFECÇÃO EXPERIMENTAL EM CAPRINOS COM Trypanosoma vivax

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    Francisco David Nascimento Sousa

    2008-10-01

    Full Text Available

    Four goats were infected intravenously with 1.0 mL of cattle blood containing about 1.25 x 105 <em>Trypanosoma vivaxem> derived from spontaneous outbreak in cattle at Catolé do Rocha city, Paraíba, Brazil. Other four goats were used as controls. Parasitemia and body temperature were determined daily for 40 days. Animals were weighted each 7 days, and blood samples for blood cells counts were collected each 5 days. It was obtained a sample of liquor from each animal before death; cerebrospinal fluid samples were submitted to biochemical and cytological evaluations, density determination and parasite detection. A positive correlation was found between body temperature and parasitemia in infected animals. These animals presented anemia, leukopenia, hypoglycemia, decreased serum levels of total proteins and cholesterol, and nervous symptoms. Examination of cerebrospinal fluid resulted in decrease of glucose levels and increase in lactate dehydrogenase, cell counts and presence of the parasite. At necropsy it was found pale carcass, generalized infartation of lymphonodes, pulmonary edema, and liquid accumulation of pericardium. Histological changes were characterized by interstitial pneumonia, miocarditis, cardiac fibrosis, meningitis, and encephalitis. All observed changes confirm patogenicity of <em>T. vivaxem>.

    KEY WORDS: Experimental infection, trypanosomiasis, patogenicity.

    Quatro caprinos foram infectados experimentalmente por via intravenosa com 1,0 ml de sangue contendo aproximadamente 1,25 x 105 tripanossomas/ml, utilizando-se um isolado de <em>Trypanosoma vivaxem> de bovinos infectados naturalmente no município de Catolé do Rocha, Paraíba. A parasitemia e a temperatura foram determinadas diariamente durante quarenta dias. A cada cinco dias realizaram-se coletas de sangue para hemograma e análise bioquímica sérica. Antes do

  14. Zoonotic trypanosomes in South East Asia : attempts to control Trypanosoma lewisi using human and animal trypanocidal drugs

    OpenAIRE

    Desquesnes, M.; Yangtara, S.; Kunphukhieo, P.; Jittapalapong, S.; Herder, Stéphane

    2016-01-01

    Beside typical human trypanosomes responsible of sleeping sickness in Africa and Chagas disease in Latin America, there is a growing number of reported atypical human infections due to Trypanosoma evansi, a livestock parasite, or Trypanosoma lewisi, a rat parasite, especially in Asia. Drugs available for the treatment of T. brucei ssp. in humans are obviously of choice for the control of T. evansi because it is derived from T. brucei. However, concerning T. lewisi, there is an urgent need to ...

  15. Aspectos ultra-estruturais da forma epimastigota do Trypanosoma cruzi em meio LIT

    Directory of Open Access Journals (Sweden)

    Wanderley de Souza

    1975-06-01

    Full Text Available E feito um estudo da ultra-estrutura da forma epismastigota do Trypanosoma cruzi mantida em meio de cultivo acelular. O núcleo das formas em divisão apresenta um aspecto homogêneo. Microtúbulos intranucleares são observados durante a divisão. No entanto, a membrana nuclear permanece íntegra. O citoplasma apresenta-se com vacúolos de dimensões e aspectos variados. Com o método do ácido periódico-tiosemicarbazida-proteinato de prata, polissacaríáeos e/ou glicoproteínas foram localizados na membrana celular e na membrana que delimita certos vacúolos citoplasmáticos.

  16. Comprehensive glycoprofiling of the epimastigote and trypomastigote stages of <em>Trypanosoma cruziem>

    DEFF Research Database (Denmark)

    Alves, Maria Julia Manso; Kawahara, Rebeca; Viner, Rosa

    2017-01-01

    Trypanosoma cruzi, the protozoan that causes Chagas disease, has a complex life cycle involving insect and mammalian hosts and distinct developmental stages. During T. cruzi developmental stages, glycoproteins play important role in the host-parasite interaction, such as cellular recognition, host...... the significant T. cruzi stage-specific expression of glycoproteins that can help to better understand the T. cruzi phenotype and response caused by the interaction with different hosts during its complex life cycle. BIOLOGICAL SIGNIFICANCE: Chagas disease caused by the protozoan Trypanosoma cruzi is a neglected...... disease which affects millions of people especially in Latin America. The absence of efficient drugs and vaccines against Chagas disease stimulates the search for novel targets. Glycoproteins are very attractive therapeutic candidate targets since they mediate key processes in the host...

  17. Estudo do papel funcional da cisteína sintase e da cistationina B-sintase na resposta ao estresse oxidativo e nitrosativo em leishmania (viannia) braziliensis, trypanosoma rangeli e trypanosoma cruzi

    OpenAIRE

    Romero Calderon, Ibeth Cristina

    2014-01-01

    Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biotecnologia e Biociências, Florianópolis, 2014 Leishmania (Viannia) braziliensis, Trypanosoma rangeli e o Trypanosoma cruzi são parasitos hemoflagelados pertencentes à Ordem Kinetoplastida, família Trypanosomatidae, capazes de infectar insetos, animais silvestres e domésticos, assim como o homem. Durante seu ciclo de vida, estes parasitos são expostos a uma grande quanti...

  18. On the tissular parasitism of Trypanosoma cruzi y strain in swiss mice Sobre o parasitismo tecidual da cepa Y do Trypanosoma cruzi em camundongos albinos (Swiss-Webster

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    Maria Auxiliadora de Sousa

    1984-12-01

    Full Text Available A review of the tissular parasitism of Trypanosoma cruzi Y strain in Swiss mice was carried out. This strain parasitized preferentially smooth, skeletal and cardiac muscle fibers, with low transitory spleen and liver parasitism, as previously found by some Authors, although differing from other reports. These results can be related to the host genetical constitution and/or the degree of the strain virulence at the time of this study. Furthermore, we discuss that the high macrophagotropism reported for this strain in some instances could be an artificially induced condition resulting from its serial maintenance in mice, either for a longer time and/or by using young animals. The heavy parasitism and inflammation observed in the bladder, pancreas and spermatic duct of some inoculated mice, as well as the testis parasitization, were also noteworthy findings.Através deste trabalho fizemos uma revisão do parasitismo tecidual da cepa Y do Trypanosoma cruzi em camundongos albinos (Swiss-Webster. Esta cepa parasitou preferencialmente as fibras musculares lisas, esqueléticas e cardíacas, sendo baixo e transitório seu parasitismo do baço e fígado, conforme já observado por alguns Autores, embora diferindo de outros achados. Estes resultados podem estar relacionados com o padrão genético do hospedeiro e/ou com o grau de virulência da cepa por ocasião deste estudo. Além do mais, discutimos a possibilidade de que o intenso macrofagotropismo descrito para esta cepa em algumas ocasiões possa ser uma condição artificialmente induzida através de sua manutenção seriada em camundongos por tempo prolongado e/ou pelo uso de animais jovens. Também são dignos de nota, o intenso parasitismo e inflamação da bexiga, pâncreas e canal espermático de alguns animais inoculados, assim como, o encontro de ninhos de amastigotas no testículo.

  19. Ação de raios gama sobre formas sanguícolas de Trypanosoma cruzi: estudo experimental em camundongos

    Directory of Open Access Journals (Sweden)

    Gentilda K. F. Takeda

    1986-02-01

    Full Text Available Amostras de sangue de animais infectados com cepa Y de Trypanosoma cruzi foram submetidas, respectivamente, a 200 e 300 krad de radiação gama. Para verificar a eficácia do método na eliminação do parasita, o material foi inoculado em camundongos e os parâmetros utilizados na avaliação foram: parasitemia, cultura, xenodiagnóstico, subinoculação, reinoculação com cepa virulenta e exame anátomo-patológico das vísceras. Os sangues expostos às duas diferentes intensidades de radiação e inoculados em dois períodos após o processo, mostraram-se inócuos quanto a capacidade de produzir infecção nos animais

  20. Insight into the exoproteome of the tissue-derived trypomastigote form of <em>trypanosoma cruziem>

    DEFF Research Database (Denmark)

    Queiroz, Rayner M L; Ricart, Carlos A O; Machado, Mara O

    2016-01-01

    The protozoan parasite Trypanosoma cruzi causes Chagas disease, one of the major neglected infectious diseases. It has the potential to infect any nucleated mammalian cell. The secreted/excreted protein repertoire released by T. cruzi trypomastigotes is crucial in host-pathogen interactions...

  1. Trypanosoma cruzi prevalence and clinical forms in blood donor candidates in Brazil Prevalência e formas clínicas de Trypanosoma cruzi em candidatos a doadores de sangue no Brasil

    Directory of Open Access Journals (Sweden)

    H J Silveira

    2003-12-01

    Full Text Available The prevalence and clinical forms of Trypanosoma cruzi were evaluated among blood donor candidates attended at a general hospital in Rio de Janeiro, Brazil, from January 1997 to April 1999. The investigation was done by means of the indirect hemagglutination test and was confirmed via ELISA. Data were collected from clinical examinations, conventional electrocardiogram, chest radiography and echocar-diography. The results showed that despite Trypanosoma cruzi prevalence of 1.17% (128 patients, mainly in males aged 40 years or over, 70.8% of these patients, mainly males aged 19 to 39 years, demonstrated abnormalities that allowed the diagnosis of cardiopathy and/or esophagopathy. This once again corroborates the importance of Trypanosoma cruzi infection in urban centers.A prevalência e a manifestação das formas clinicas de Trypanosoma cruzi foram avaliadas em candidatos a doadores de sangue atendidos em um hospital geral de Nova Iguaçu, Rio de Janeiro, Brasil, no período de janeiro de 1997 a abril de 1999. A pesquisa sorológica foi realizada por meio do teste de hemaglutinação indireta e confirmada pelo ELISA. Os dados foram coletados considerando os exames clínicos, eletrocardiograma convencional, radiografia de tórax e ecocardiografia. Os resultados demonstraram que, apesar da prevalência ser de 1,17% (128 pacientes, principalmente entre homens com idade igual ou superior a 40 anos, 70,8%, principalmente de homens entre 19 e 39 anos, demonstraram alterações que permitiram o diagnóstico de cardiopatias e/ou esofagopatias, ratificando mais uma vez sua importância nos centros urbanos.

  2. Seleção para alto teor de acilaçúcares em genótipos de tomateiro e sua relação com a resistência ao ácaro vermelho (Tetranychus evansi e à traça (Tuta absoluta Selection towards high acylsugar levels in tomato genotypes and its relationship with resistance to spider mite (Tetranychus evansi and to the South American pinworm (Tuta absoluta

    Directory of Open Access Journals (Sweden)

    Guilherme Victor Nippes Pereira

    2008-06-01

    Full Text Available Uma das estratégias do melhoramento do tomateiro, no Brasil, visando à resistência a pragas, tem sido a utilização de aleloquímicos presentes nos folíolos. Objetivou-se no presente trabalho, estudar os níveis de resistência a dois artrópodos-pragas [traça do tomateiro (Tuta absoluta e ácaros (Tetranychus evansi], em genótipos previamente selecionados com base apenas no seu teor foliar de acilaçúcares. Foram selecionadas 11 plantas contrastantes quanto aos níveis de acilaçúcares nos folíolos, de uma população F3RC2, derivada do cruzamento interespecífico Lycopersicon esculentum Mill 'TOM-584' x Lycopersicon pennellii (Correll D'Arcy 'LA-716'. Esses genótipos, juntamente com os genitores TOM-584 e LA-716, foram submetidos a ensaios de repelência/resistência a artrópodos-pragas. No teste de repelência ao ácaro T. evansi, as plantas com altos teores de acilaçúcares se comportaram de forma semelhante ao genitor resistente LA-716. As magnitudes das correlações foram negativas e significativas, confirmando assim a associação entre altos teores do aleloquímico e a resistência (repelência ao ácaro, avaliada pela distância percorrida. No ensaio realizado com a traça do tomateiro, os genótipos foram avaliados para danos nas plantas e lesões nos folíolos. Os genótipos contendo alto teor de acilaçúcares, demonstraram bons níveis de resistência a Tuta absoluta, não diferindo significativamente do acesso selvagem LA-716. Em todas as épocas de avaliação, os teores de acilaçúcares mostraram-se alta e negativamente correlacionados com os níveis de dano causados pela traça. Os resultados obtidos comprovaram a eficiência da seleção de genótipos de tomateiro com elevados teores de acilaçúcares nos folíolos, visando à resistência a artrópodos-praga.Selection for high foliar levels of allelochemicals has been proposed as a suitable strategy for breeding tomatoes for arthropod pest resistance. In the

  3. Lesões cardíacas em ratos wistar inoculados com diferentes cepas do Trypanosoma cruzi

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    E. Chapadeiro

    1988-09-01

    Full Text Available Ratos albinos Wistar infectados com diferentes inóculos das cepas Y, Colombiana (COL e São Felipe (12SF do Trypanosoma cruzi desenvolveram parasitemia elevada entre 14e21 dias, a qual tomou-se desprezível ou desapareceu completamente ao final da 4ª semana. As lesões do coração foram avaliadas, semiquantitativamente, pelo sistema de "scores", conforme a intensidade e a extensão da inflamação, nas diferentes estruturas do órgão, tendo sido observado que: a na fase inicial (aguda da infecção, os animais mortos espontaneamente ou em conseqüência de acidente anestésico apresentaram cardite de intensidade moderada à acentuada, não havendo diferença em relação às cepas utilizadas; as diferentes estruturas do coração estavam uniformemente comprometidas; b na fase crônica da infecção observou-se cardite degrau leve a moderado e as lesões foram mais freqüentes e intensas quanto maior o inoculo empregado; no entanto, inóculos baixos só produziram lesões quando a cepa utilizada foi a Colombiana. Trombose mural nos átrios e dilatação da ponta do ventrículo esquerdo foram observadas em 20% dos animais, independentemente da cepa. Na fase crônica 15% dos animais apresentaram miocardite crônica com fibrose, associada à hipertrofia das miocélulas. Os AA confirmam ser o rato albino suscetível à infecção chagásica e, portanto, um modelo útil no estudo das manifestações cardíacas da Doença de Chagas.

  4. Neuronal counting and parasympathetic dysfunction in the hearts of chronically Trypanosoma cruzi - infected rats Contagem neuronal e disfunção cardíaca parassimpática em ratos cronicamente infectados pelo Trypanosoma cruzi

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    E. Chapadeiro

    1991-10-01

    Full Text Available Ten male Wistar rats, chronically infected with Colombian, São Felipe (12SF and Y strains of Trypanosoma cruzi and ten non-infected control animals were submitted to the bradycardia responsiveness test, an assessment of heart parasympathetic function, after phenylephrine injection. Six chagasic animals showed heart parasympathetic dysfuntion characterized by reduction in the index of bradycardia baroreflex responsiveness, as compared with the control group. Microscopic examination of the atrial heart ganglia of chagasic rats showed ganglionitis, but no statiscally significant reduction in the number of neurons.Dez ratos machos Wistar cronicamente infectados pelas cepas Colombiana, São Felipe (12SF, e Y do Trypanosoma cruzi, foram submetidos, após 8 meses de infecção, juntamente com dez animais controles, ao teste da resposta bradicárdica barorreflexa pela injeção endovenosa de fenilefrina. Seis ratos chagásicos exibiram disfunção cardíaca parassimpática, caracterizada pela depressão do índice da resposta bradicárdica barorreflexa. Embora o estudo histológico dos corações chagásicos mostrasse lesões dos gânglios atriais, a contagem dos neurônios em cortes seriados, não apresentou redução numérica significativa dos mesmos.

  5. Trypanosoma (Herpetosoma rangeli Tejera, 1920: nota prévia sobre a histopatologia em camundongos infectados experimentalmente

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    Cecilia de Scorza

    1986-10-01

    Full Text Available Ratones machos (cepa NMRI de 3 y 5 gr, inoculados i.p. con 8 x 10(6 y 9 x 10(4 metatripo- mastigotes/gr cosechados de cultivo LIT de 12 días de repique de la cepa "Perro-82" de Trypanosoma rangeli fueron procesados, em determinados períodos postinoculación, para seccionar y teñir con hematoxilina-eosina y Giemsa-colofonio trozos de corozón, hígado, bazo, pulmones, fémur, riñon, intestino, estómago, cerebro, cerebelo, esternón y columna vertebral. Se detallan los resultados preliminares sobre la histopatologia provocada por el T. rangeli en los cinco primeros órganos citados. Los tejidos conjuntivos subcutáneo, periosteal, intersticial y peribronquial, así como las miocélulas del corazón fueron altamente parasitados por amastigotes y tripomastigotes. Se discuten las posibles razones de la disminución del parasitismo tisular cuando la parasitemia se encontró en sus niveles máximos, así como la escasa inflamación obtenida en los tejidos parasitados. Las observaciones de varios autores sobre el comportamiento del protozoario en humanos y en animales de laboratorio así como los resultados descritos en este trabajo, plantean la posibilidad de que determinadas cepas de T. rangeli, en condiciones particulares, podrían causar alteraciones patológicas en el mamífero.

  6. Seroprevalence of human Trypanosoma cruzi infection in diferent geografic zones of Chiapas, Mexico Soroprevalência da infecção humana pelo Trypanosoma cruzi em diferentes regiões de Chiapas, México

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    Miguel Angel Mazariego-Arana

    2001-10-01

    Full Text Available A serologic survey was carried out in four different geographic zones of Chiapas, Mexico. A total of 1,333 samples were collected from residents of thirteen communities located on the Coast, Central Mountain, Lacandon Forest and a zone called Mesochiapas. One hundred and fifty one seropositive individuals (11.3% were identified. Human Trypanosoma cruzi infection was influenced by geography. In the Lacandon Forest and Central Mountains there was a higher seroprevalence 32.1 and 13.8% respectively, than on the coast (1.2%. In Mesochiapas there were no seropositive individuals among the 137 persons tested. An active transmission is probably continuing because seropositive cases (13.8% were detected in children under 10 years of age. The vector recognized on the Coast was Triatoma dimidiata while in the Lacandon Forest it was Rhodnius prolixus.Foi feito um estudo sorológico em quatro zonas geográficas do estado de Chiapas México. Foram colhidas 1333 amostras dos habitantes das 13 comunidades situadas na costa, na região central montanhosa, na floresta lacandona e na região chamada mesochiapas. Cento cinqüenta e uma pessoas (11,3% foram identificadas como soropositivas. A infecção pelo Trypanosoma cruzi teve a influência da geografia local. Na floresta lacandona nas montanhas centrais, foi encontrada uma prevalência de 32,1 e 13,8% respectivamente, mais que na costa 1,2%. Na zona de mesochiapas não foi encontrada nenhuma pessoa com sorologia positiva entre 137 estudadas. Como encontramos sorologia positiva em crianças menores de 10 anos, pensamos que exista uma transmissão ativa contínua. Na costa foi reconhecido o vetor Triatoma dimidiata e na floresta Lacandona o Rhodnius prolixus.

  7. Reativação da infecção por Trypanosoma cruzi em paciente com síndrome de imunodeficiência adquirida

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    Galhardo Maria Clara Gutierrez

    1999-01-01

    Full Text Available Uma paciente com síndrome de imunodeficiência adquirida (SIDA e doença de Chagas, com xenodiagnóstico positivo, estava em uso prolongado de cetoconazol com o objetivo de suprimir a parasitemia e prevenir a reativação da doença de Chagas. O cetoconazol foi suspenso inadvertidamente após 6 meses de uso. Um mês após, a paciente foi internada com febre, cefaléia, vômitos, taquicardia e hepatoesplenomegalia. Tanto o xenodiagnóstico como o exame de sangue a fresco demonstraram a presença de Trypanosoma cruzi. O tratamento com benzonidazol foi instituído, com supressão da parasitemia. A paciente desenvolveu concomitantemente uma provável neurotoxoplasmose, evoluindo para o óbito em septicemia. À necropsia, não foram encontrados parasitas.

  8. Action of the medicine Canova® on peritoneal resident macrophages infected with Trypanosoma cruzi = Ação do medicamento Canova® em macrófagos peritoniais residentes infectados por Trypanosoma cruzi

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    Vanessa Tagawa Cardoso de Oliveira

    2008-01-01

    Full Text Available Approximately 20 million of people are chronically infected withTrypanosoma cruzi in Latin America. The present work investigated the action of the homeopathic medicine Canova® on in vitro experimental infections with T. cruzi Y strain, using Swiss mice resident peritoneal macrophages. Our results demonstrated that Canova®induced a decrease in the production of H2O2 and TNF-a at 20 and 40% concentrations when compared to the control RPMI. However, when compared with this medicine excipient, a significant decrease in these mediators was observed with Canova® at 40% concentration only. The production of NO and phagocytic activity were not affected. TNF-a inhibits T. cruzi replication in peritoneal macrophages in vitro, becoming an important agent of infection control by this parasite. Within this context, Canova®, unlike what has been reported with other infections, would function as a stimulator of the infection, since it inhibited the production of TNF-α by peritoneal resident macrophages in vitro. Further studies should be carried out with elicited macrophages, in order to confirm the inhibitoryactivity of Canova® on the production of TNF-α and other mediators in macrophages infected by T. cruzi.Aproximadamente 20 milhões de pessoas são cronicamente infectadas pelo Trypanosoma cruzi na América Latina. O presente trabalhoinvestigou a ação do medicamento homeopático Canova® em infecções experimentais “in vitro” com Trypanosoma cruzi, cepa Y, usando macrófagos residentes peritoniais de camundongos Swiss. Os resultados indicaram que Canova® induz a diminuição significativa da produção de H2O2 e TNF-α em concentrações de 20 e 40%, quando comparado com ocontrole RPMI. Quando comparado com o excipiente do medicamento, observou-se diminuição na concentração destes mediadores apenas na concentração de 40%. A produção de NO e a atividade fagocítica não foram afetadas. TNF-α inibe a replicação do protozoário em

  9. Modificações nucleares em células parasitadas pelo Trypanosoma cruzi em chagásicos crônicos

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    Hipólito de Oliveira Almeida

    1987-09-01

    Full Text Available Através do estudo da musculaturalisa da parede da veia central das supra-renais de chagásicos crônicos foram identificados núcleos em 18 dentre 40 células parasitadaspelo Trypanosoma cruzi. Com o auxílio de uma ocular micrométrica foram tomados dois diâmetros de cada ninho e núcleo, obtendo-se suas médias e desvios padrões (25,7 µm ± 17,2 e 12 µm ± 5,3 e 7,5 µm ± 2,82 para diâmetros dos ninhos e dos núcleos para células mononucleadas e binucleadas respectivamente. A relação diâmetro do núcleo/diâmetro do ninho foi de 0,5 ± 0,16. 83,3% dos ninhos eram mononucleados e apenas 16,7% binucleados. A média do volume nuclear para as células parasitadas foi de 1204µm³ ± 807,0 e para as células musculares lisas não parasitadasfoi de 69,6µm ± 7,2. A forma e o contorno nucleares eram variados e irregulares. Os núcleos hipercromáticos ou vesiculosos, com membrana cromatínica geralmente espessa e bem definida, freqüentemente mostrando um a dois nucléolos por secção, podendo, no entanto, serem encontrados até 8 nucléolos. Sendo as alterações nucleares descritas freqüentes nos chagásicos crônicos, épossível que sejam a expressão morfológica de importantes interações entre o T. cruzi e o leiomiócito.

  10. Survival of Trypanosoma cruzi in sugar cane used to prepare juice Avaliação da sobrevida de Trypanosoma cruzi em cana de açúcar utilizada no preparo do caldo

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    Adriana V.N. Cardoso

    2006-10-01

    Full Text Available Chagas disease can be transmitted to man by many different means, including contact with infected triatomine feces, blood transfusion, laboratory accidents, organ transplants, and congenital or oral routes. The latter mode has received considerable attention recently. In this assay, we evaluate the survival of Trypanosoma cruzi contaminating sugar cane used to prepare juice, as well as the viability and capacity for infection by the parasite after recovery. Thirty triatomines were contaminated with T. cruzi Y strain and 45 days later pieces of sugar cane were contaminated with the intestinal contents of the insects. The pieces were ground at different intervals after contamination (time = 0, 1, 4, 6, 12 and 24 hours and the juice extracted and analyzed. Different methods were used to show T. cruzi in the juice: direct analysis, hematocrit tube centrifugation and QBC, and experimental inoculation in 47 female BALB/c mice (five control mice and seven mice for each interval examined (five inoculated orally and two intraperitoneally. Positive results were found using the direct analysis and QBC methods for juice prepared up to 12 hours after initial contamination. However, by the centrifugation technique, positivity was found only up to four hours after contamination of the sugar cane. Inoculated animals showed parasitemia during a 14 day observation period, demonstrating the high survival rate of T. cruzi in sugar cane.A doença de Chagas pode ser transmitida ao homem através de vários mecanismos: fezes de triatomíneo infectado; transfusão sangüínea; acidente em laboratório; transplante de órgão; vias congênita ou oral convindo salientar que esta última tem motivado ocorrências recentemente. Neste estudo procuramos avaliar a sobrevida de Trypanosoma cruzi presente em cana de açúcar contaminada com o parasita, utilizada no preparo do caldo e, também, a viabilidade e a capacidade de infecção do parasita depois de ser recuperado

  11. Melophagus ovinus e Trypanosoma (Megatrypanum melophagium em ovinos no Estado de Minas Gerais, Brasil Melophagus ovinus and Trypanosoma (Megatrypanum melophagium in ovines in the State of Minas Gerais, Brasil

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    José Oswaldo Costa

    1983-03-01

    Full Text Available Neste trabalho Melophagus ovinus é identificado pela primeira vez no Estado de Minas Gerais e Trypanosoma (Megatrypanum melophagium tem sua primeira ocorrência registrada no Brasil.Melophagus ovinus is identified for the first time in Minas Gerais State and Trypanosoma (Megatrypanum melophagium in Brazil.

  12. Detection of Trypanosoma cruzi and Trypanosoma rangeli infection in triatomine vectors by amplification of the histone H2A/SIRE and the sno-RNA-C11 genes Detecção da infecção por Trypanosoma cruzi e Trypanosoma rangeli em vetores triatomíneos através da amplificação dos gens de histona H2A/SIRE e sno-RNA-C11

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    Paula Ximena Pavia

    2007-02-01

    Full Text Available Trypanosoma rangeli is non pathogenic for humans but of important medical and epidemiological interest because it shares vertebrate hosts, insect vectors, reservoirs and geographic areas with T. cruzi, the etiological agent of Chagas disease. Therefore, in this work, we set up two PCR reactions, TcH2AF/R and TrFR2, to distinguish T. cruzi from T. rangeli in mixed infections of vectors based on amplification of the histone H2A/SIRE and the small nucleolar RNA Cl1 genes, respectively. Both PCRs were able to appropriately detect all T. cruzi or T. rangeli experimentally infected-triatomines, as well as the S35/S36 PCR which amplifies the variable region of minicircle kDNA of T. cruzi. In mixed infections, whereas T. cruzi DNA was amplified in 100% of samples with TcH2AF/R and S35/S36 PCRs, T. rangeli was detected in 71% with TrF/R2 and in 6% with S35/S36. In a group of Rhodnius colombiensis collected from Coyaima (Colombia, T. cruzi was identified in 100% with both PCRs and T. rangeli in 14% with TrF/R2 and 10% with S35/S36 PCR. These results show that TcH2AF/R and TrF/R2 PCRs which are capable of recognizing all T. cruzi and T. rangeli strains and lineages could be useful for diagnosis as well as for epidemiological field studies of T. cruzi and T. rangeli vector infections.Embora o Trypanosoma rangeli não seja patogênico para o homem, sua importância médica e epidemiológica reside no fato de compartilhar vetores, reservatórios e áreas geográficas com o Trypanosoma cruzi, agente causal da Doença de Chagas. Neste estudo, para distinguir T. cruzi de T. rangeli em vetores com infecções mistas, se utilizaram duas amplificações de PCR; TcH2AF/R para o gen da histona H2A/SIRE e TrFR2, para um gen repetitivo de ARN nucleolar Cl1 (sno-RNA-Cl1. Assim como a PCR S35/S36, ambas as reações foram capazes de detectar corretamente a presença de T. cruzi ou T. rangeli em triatomíneos infectados experimentalmente. Nas infecções mistas, o ADN de

  13. Efeito protetor do benznidazol contra a reativação parasitária em pacientes cronicamente infectados pelo Trypanosoma cruzi e tratados com corticóide em virtude de afecções associadas

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    Rassi Anis

    1999-01-01

    Full Text Available Pacientes na fase crônica da doença de Chagas foram tratados com corticóide em virtude de afecções associadas e, a fim de tentar coibir reativação da infecção pelo Trypanosoma cruzi, houve administração do benznidazol, iniciada concomitantemente em um grupo de 12 pacientes, ou 15 dias após o começo do uso daquele medicamento em outro grupo de 6. Levando em conta o verificado em pesquisa anterior, quando corticóide de fato promoveu aumento da parasitemia, como ainda valorizando os resultados de xenodiagnóstico, pôde ser notado que o benznidazol mostrou-se apto a evitar a citada acentuação parasitária, podendo tal constatação ser útil em procedimentos assistenciais, quando estiverem presentes doença de Chagas e imunodepressão.

  14. Modificações nucleares em células parasitadas pelo Trypanosoma cruzi em chagásicos crônicos

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    Hipólito de Oliveira Almeida

    1987-09-01

    Full Text Available Através do estudo da musculaturalisa da parede da veia central das supra-renais de chagásicos crônicos foram identificados núcleos em 18 dentre 40 células parasitadaspelo Trypanosoma cruzi. Com o auxílio de uma ocular micrométrica foram tomados dois diâmetros de cada ninho e núcleo, obtendo-se suas médias e desvios padrões (25,7 µm ± 17,2 e 12 µm ± 5,3 e 7,5 µm ± 2,82 para diâmetros dos ninhos e dos núcleos para células mononucleadas e binucleadas respectivamente. A relação diâmetro do núcleo/diâmetro do ninho foi de 0,5 ± 0,16. 83,3% dos ninhos eram mononucleados e apenas 16,7% binucleados. A média do volume nuclear para as células parasitadas foi de 1204µm³ ± 807,0 e para as células musculares lisas não parasitadasfoi de 69,6µm ± 7,2. A forma e o contorno nucleares eram variados e irregulares. Os núcleos hipercromáticos ou vesiculosos, com membrana cromatínica geralmente espessa e bem definida, freqüentemente mostrando um a dois nucléolos por secção, podendo, no entanto, serem encontrados até 8 nucléolos. Sendo as alterações nucleares descritas freqüentes nos chagásicos crônicos, épossível que sejam a expressão morfológica de importantes interações entre o T. cruzi e o leiomiócito.By the study of histological sections of smooth muscle in the wall of the adrenal vein in human chronic Chagas'disease 18 nuclei were identified in 40 cells parasitized by T. cruzi. With an ocular micrometer two diameters of each nest and their nucleus were taken, obtaining their mean size and standard deviation (SD (25.7 µm ± 17.2 for nest diameters and 12 µm ± 5.3 and 7.5 pm ± 2.82 for the nuclear diameters of the mononucleated and binucleated cells respectively. The relation nucleus diameter/nest diameter was 0.5 ± 0.16. 83.3% of the nests had one nucleus and 16.7% were binucleated. The mean nuclear volume of the parasitized cells was 1204 µm³ ± 807.0 and of the non parasitized smooth muscle cells

  15. Zoonotic trypanosomes in South East Asia: Attempts to control Trypanosoma lewisi using human and animal trypanocidal drugs.

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    Desquesnes, Marc; Yangtara, Sarawut; Kunphukhieo, Pawinee; Jittapalapong, Sathaporn; Herder, Stéphane

    2016-10-01

    Beside typical human trypanosomes responsible of sleeping sickness in Africa and Chagas disease in Latin America, there is a growing number of reported atypical human infections due to Trypanosoma evansi, a livestock parasite, or Trypanosoma lewisi, a rat parasite, especially in Asia. Drugs available for the treatment of T. brucei ssp. in humans are obviously of choice for the control of T. evansi because it is derived from T. brucei. However, concerning T. lewisi, there is an urgent need to determine the efficacy of trypanocidal drugs for the treatment in humans. In a recent study, pentamidine and fexinidazole were shown to have the best efficacy against one stock of T. lewisi in rats. In the present study suramin, pentamidine, eflornitine, nifurtimox, benznidazole and fexinidazole, were evaluated at low and high doses, in single day administration to normal rats experimentally infected with a stock of T. lewisi recently isolated in Thailand. Because none of these treatments was efficient, a trial was made with the most promising trypanocide identified in a previous study, fexinidazole 100mg/kg, in 5 daily administrations. Results observed were unclear. To confirm the efficacy of fexinidazole, a mixed infection protocol was set up in cyclophosphamide immunosuppressed rats. Animals were infected successively by T. lewisi and T. evansi, and received 10 daily PO administrations of 200mg/kg fexinidazole. Drastic effects were observed against T. evansi which was cleared from the rat's blood within 24 to 48h; however, the treatment did not affect T. lewisi which remained in high number in the blood until the end of the experiment. This mixed infection/treatment protocol clearly demonstrated the efficacy of fexinidazole against T. evansi and its inefficacy against T. lewisi. Since animal trypanocides were also recently shown to be inefficient, other protocols as well as other T. lewisi stocks should be investigated in further studies. Copyright © 2016. Published by

  16. Tipificación molecular por PCR-RFLPS de cepas trypanosoma sp. aisladas en campo y evaluación de ganados de la Orinoquia colombiana

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    Elizabeth Regina Cassalett Bustillo

    2006-07-01

    correspondieron a la cepa Trypanosoma theileri en un 80%, y un 20% a la cepa Trypanosoma vivax. Los resultados que se obtuvieron del estudio morfométrico en las especies T. vivax y T. evansi del Banco de Germoplasma de Corpoica, mostraron que el T. vivax es un parásito con mayor longitud (20-25 μm que el T. evansi (18-19 μm, aunque el flagelo libre de este último siempre fue mayor (7-9 μm al igual que el diámetro de su núcleo. En ambos parásitos la posición del núcleo fue central y la posición del quinetolasto terminal.

  17. Infection by Trypanosoma cruzi in mammals in Yucatan, Mexico: a serological and parasitological study Infecção pelo Trypanosoma cruzi em mamíferos em Yucatan, México: estudo sorológico e parasitológico

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    J Zavala-Velázquez

    1996-08-01

    Full Text Available In order to determine Trypanosoma cruzi infection among mammals in Yucatan, Mexico, 372 animals, both wild and synanthropic including carnivores, marsupials and rodents were studied. Serological studies by indirect haemagglutination (IHA were carried out to detect antibodies to T. cruzi and a parasitological study was also performed (blood smear and histopathology. Of all the animals tested 18.54% were serologically positive, with a significantly higher frequency among the wild ones (33.33% compared to the synanthropic ones (17.79%. To determine T. cruzi in positive animals, blood was inoculated into a white mouse (webster type to prove myocardium colonization. The serological and parasitological positivity of these animals, as well as their behavior in the environment, taken together with the socioeconomic and cultural characteristics of the population, suggest that in Yucatan, Mexico, Canis familiaris, Didelphis marsupialis and Rattus rattus act as a link with the wild cycle.Para determinar a infecção pelo Trypanosoma cruzi em mamíferos em Yucatan, México, foram estudados 372 animais selvagens e sinantrópicos incluindo carnívoros, marsupiais e roedores. Estudos sorológicos pela hemaglutinação indireta (IHA foram realizados para detectar anticorpos contra o T. cruzi e estudos parasitológicos (esfregaços de sangue e histopatologia. De todos os animais testados 18,54% foram sorologicamente positivos com freqüência significativamente maior entre os silvestres (33,3% em comparação com os sinantrópicos (11,79%. Para determinação do T. cruzi nos animais positivos, o sangue foi inoculado em camundongos brancos (tipo Webster para provar a colonização miocárdica. Através da sua positividade sorológica e parasitológica, bem como seu comportamento no meio ambiente acompanhado pelas características sociais, econômicas e culturais da população, deduz-se que em Yucatan, México, Canis familiaris, Didelphis marsupialis e Rattus

  18. Infecção experimental pelo Trypanosoma cruzi em camundongos: influência do exercício físico versus linhagens e sexos

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    Roberta Cristhiany Occhi Soares

    2012-02-01

    Full Text Available INTRODUÇÃO: A doença de Chagas é uma infecção causada pelo Trypanosoma cruzi que afeta oito milhões de pessoas na América Latina. Um fator ligado ao estilo de vida que interfere significativamente na resposta à infecção é o exercício físico, dependendo do tipo, intensidade e frequência da atividade praticada. OBJETIVO: Avaliar a influência do exercício físico aeróbio moderado crônico pré-infecção na evolução da infecção experimental pelo T. cruzi em camundongos de duas linhagens distintas pertencentes aos dois sexos. MÉTODOS: Camundongos Swiss e BALB/c (machos e fêmeas com 30 dias de idade foram divididos em quatro grupos para cada linhagem e sexo (total de 16 e nomeados como segue: SM (Swiss machos, SF (Swiss fêmeas, BM (BALB/c machos e BF (BALB/c fêmeas. Os grupos foram: NT+NI (não treinado+não infectado, T+NI (treinado+não infectado, NT+I (não treinado+infectado e T+I (treinado+infectado. O programa de exercício físico aeróbio moderado crônico pré-infecção foi realizado durante oito semanas, com uma sessão diária de treinamento, cinco vezes na semana. O inóculo foi de 1.400 tripomastígotas sanguíneos da cepa Y do T. cruzi, via intraperitoneal. Foi avaliado o pico de parasitos, parasitemia total média e as medidas das atividades séricas de CK e CK-MB. RESULTADOS E CONCLUSÃO: O treinamento físico promoveu nas duas linhagens e em ambos os sexos redução no pico de parasitos e na parasitemia total média em animais infectados pelo T. cruzi. O treinamento físico promoveu redução nas atividades séricas de CK e CK-MB em animais infectados pelo T. cruzi, de ambos os sexos, das duas linhagens, exceto para fêmeas Swiss na atividade de CK e CK-MB.

  19. First report of Trypanosoma vivax outbreak in dairy cattle in São Paulo state, Brazil Primeiro relato de surto por Trypanosoma vivax em vacas leiteiras no estado de São Paulo, Brasil

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    Fabiano Antonio Cadioli

    2012-06-01

    Full Text Available This is the first description of a Trypanosoma vivax outbreak in the state of São Paulo (municipality of Lins. Fever, jaundice, decreased milk production, weight loss, profuse diarrhea, abortion, anemia, leukocytosis and hyperfibrinogenemia were observed in the affected animals. Thirty-one cows and calves died out of a total of 1080 in the herd. Three cows showed neurological symptoms like dysmetria, ataxia, muscle weakness, ptyalism, lymph node enlargement and submandibular edema. Flagellated hemoparasites were observed in blood smears. The species was diagnosed as T. vivax by means of PCR. This T.vivax strain showed resistance to diaminazene aceturate and the infection spread quickly at the herd. From the ELISA test, 599 serum samples (98.36% were positive for anti-T.vivax IgG antibodies. This outbreak occurred during a very dry period, which indicates that other factors were involved in the outbreak, such as absence of tabanids and large populations of Haematobia irritans and Stomoxys calcitrans. The increases in these populations may have been due to the use of biosolid waste from sugar and ethanol plants in the sugarcane plantations surrounding the dairy farm.Esta é a primeira descrição de um surto de Trypanosomavivax ocorrido no Estado de São Paulo, no município de Lins. Animais acometidos apresentaram febre, icterícia, diminuição da produção de leite, perda de peso, diarreia profusa, abortos, anemia, leucocitose e hiperfibrigenemia. Foram registrados 31 óbitos de vacas e bezerros em 1.080 bovinos no total. Três vacas apresentaram sintomatologia nervosa, como dismetria, ataxia e fraqueza muscular, além de ptialismo, aumento de linfonodos e edema submandibular. Hemoparasitas flagelados foram observados em esfregaços sanguíneos, e a espécie de tripanossomo foi diagnosticada como T.vivax por PCR. A cepa de T. vivax mostrou ser resistente ao tratamento com aceturato de diaminozeno e a infecção disseminou rapidamente no

  20. Evaluation of the immune response to CRA and FRA recombinant antigens of Trypanosoma cruzi in C57BL/6 mice Avaliação da resposta imune em camundongos C57BL/6 imunizados com os antígenos recombinantes CRA e FRA de Trypanosoma cruzi

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    Valéria Rêgo Alves Pereira

    2003-07-01

    Full Text Available Humoral and cellular immune responses were evaluated in 44 C57BL/6 mice immunized with the Trypanosoma cruzi recombinant antigens CRA and FRA. Both antigens induced cutaneous immediate-type hypersensitivity response. The levels of IgG1, IgG2a, IgG2b and IgG3 were high in CRA immunized mice. IgG3 was the predominant isotype. Although no difference in antibody levels was observed in FRA-immunized mice when compared to control mice, both antigens were able to induce lymphoproliferation in immunized mice. Significant differences were observed between incorporation of [³H]- thymidine by spleen cell stimulated in vitro with CRA or FRA and the control group. These results suggest that CRA and FRA could be involved in mechanisms of resistance to Trypanosoma cruzi infection.As respostas imune humoral e celular foram avaliadas em 44 camundongos C57Bl/6 imunizados com os antígenos recombinantes CRA e FRA de Trypanosoma cruzi. Ambos antígenos induziram reação de hipersensibilidade do tipo imediato. Os níveis de IgG1, IgG2a, IgG2b e IgG3 foram elevados nos camundongos imunizados com CRA. IgG3 foi o isotipo predominante. Nenhuma diferença nos níveis de anticorpos foi observada em camundongos imunizados com FRA em relação aos animais controle. No entanto, ambos antígenos foram capazes de induzir proliferação de linfócitos em camundongos imunizados. Diferenças significativas foram observadas entre a incorporação da timidina - [³H] pelas células esplênicas estimuladas com CRA ou FRA e o grupo controle. Esses resultados sugerem que CRA e FRA poderão estar envolvidos nos mecanismos de resistência à infecção pelo Trypanosoma cruzi.

  1. Caracterização da interação RPA-1-telômero em Trypanosoma cruzi.

    OpenAIRE

    Raphael Souza Pavani

    2014-01-01

    O complexo telomérico, responsável pela integridade genômica, é formado pela interação de DNA com proteínas, que são responsáveis pela proteção desses terminais. O complexo RPA de eucariotos compreende um heterotrímero, que cumpre diversas funções vitais na célula, sendo uma peça fundamental na replicação, reparo e recombinação. A ausência de homólogos de proteínas que protegem o telômero em T. cruzi nos fez investigar se o complexo RPA poderia cumprir essa função. Assim, este trabalho teve ...

  2. Molecular characterization and classification of Trypanosoma spp. Venezuelan isolates based on microsatellite markers and kinetoplast maxicircle genes.

    Science.gov (United States)

    Sánchez, E; Perrone, T; Recchimuzzi, G; Cardozo, I; Biteau, N; Aso, P M; Mijares, A; Baltz, T; Berthier, D; Balzano-Nogueira, L; Gonzatti, M I

    2015-10-15

    Livestock trypanosomoses, caused by three species of the Trypanozoon subgenus, Trypanosoma brucei brucei, T. evansi and T. equiperdum is widely distributed throughout the world and constitutes an important limitation for the production of animal protein. T. evansi and T. equiperdum are morphologically indistinguishable parasites that evolved from a common ancestor but acquired important biological differences, including host range, mode of transmission, distribution, clinical symptoms and pathogenicity. At a molecular level, T. evansi is characterized by the complete loss of the maxicircles of the kinetoplastic DNA, while T. equiperdum has retained maxicircle fragments similar to those present in T. brucei. T. evansi causes the disease known as Surra, Derrengadera or "mal de cadeiras", while T. equiperdum is the etiological agent of dourine or "mal du coit", characterized by venereal transmission and white patches in the genitalia. Nine Venezuelan Trypanosoma spp. isolates, from horse, donkey or capybara were genotyped and classified using microsatellite analyses and maxicircle genes. The variables from the microsatellite data and the Procyclin PE repeats matrices were combined using the Hill-Smith method and compared to a group of T. evansi, T. equiperdum and T. brucei reference strains from South America, Asia and Africa using Coinertia analysis. Four maxicircle genes (cytb, cox1, a6 and nd8) were amplified by PCRfrom TeAp-N/D1 and TeGu-N/D1, the two Venezuelan isolates that grouped with the T. equiperdum STIB841/OVI strain. These maxicircle sequences were analyzed by nucleotide BLAST and aligned toorthologous genes from the Trypanozoon subgenus by MUSCLE tools. Phylogenetic trees were constructed using Maximum Parsimony (MP) and Maximum Likelihood (ML) with the MEGA5.1® software. We characterized microsatellite markers and Procyclin PE repeats of nine Venezuelan Trypanosoma spp. isolates with various degrees of virulence in a mouse model, and compared them to a

  3. Reinfections with strains of Trypanosoma cruzi, of different biodemes as a factor of aggravation of myocarditis and myositis in mice Reinfecções com cepas do Trypanosoma cruzi de diferentes biodemas como fator agravante da miocardite e miosite em camundongos

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    Sonia Gumes Andrade

    2006-02-01

    Full Text Available Reinfections with Trypanosoma cruzi in patients from endemic areas have been claimed to be an aggravation factor of cardiac manifestations in Chagas' disease. In the present study, the influence of triple infections with strains of different biodemes, on cardiac and skeletal muscle lesions was experimentally tested. Fifty eight mice chronically infected with the Colombian strain (Biodeme Type III were successively reinfected as follows: 1st group - reinfected with 21 SF strain (Type II followed by Y strain (Type I ; 2nd - group reinfections with Y strain followed by 21SF strain. Isoenzyme analysis of parasites from hemocultures obtained from triple infected mice, revealed the patterns of three distinct zymodemes in the same animal. Each Trypanosoma cruzi strain was reisolated after four passages in mice on either the 7th, 14th or 30th day after inoculation with the blood of triple infected mice. Histopathology results demonstrated a significant exacerbation of cardiac and skeletal muscle inflammatory lesions, confirmed by morphometric evaluation, in mice with triple infection. No aggravation of parasitism was detected. The possibility of an enhancement of cellular response in the triple infected mice is suggested.Reinfecções pelo Trypanosoma cruzi em pacientes de áreas endêmicas têm sido mencionadas como fator agravante das manifestações cardíacas na doença de Chagas. No presente estudo, a influência da tríplice infecção com cepas de diferentes biodemas, sobre as lesões do miocárdio e de músculo esquelético foi investigada experimentalmente. Cinqüenta e oito camundongos cronicamente infectados com a cepa Colombiana do Trypanosoma cruzi (Biodema Tipo III foram sucessivamente reinoculadas como a seguir: 1º grupo - reinfectados com a cepa 21 SF (Tipo II seguido pela cepa Y (Tipo I; 2º grupo - reinfecção com a cepa Y seguida pela cepa 21SF. A análise isoenzimática dos parasitas das hemoculturas obtidas dos animais com tr

  4. [Morphological abnormalities in the cibarium of Lutzomyia evansi (Diptera: Psychodidae, Phlebotominae) caught in Trujillo, Venezuela].

    Science.gov (United States)

    Méndez-de Daboín, Yolanda; Oviedo-Araújo, Milagros; González-Pérez, Adalberto; Suárez-Hernández, Jorge; Sandoval, Claudia M; Cazorla, Dalmiro

    2015-01-01

    Lutzomyia evansi is a recognized vector of Leishmania infantum in Colombia and Venezuela. To describe and illustrate the morphological abnormalities in Lu. evansi females captured in a rural focus of visceral leishmaniasis in Trujillo, Venezuela. Phlebotomine sand flies were collected using CDC light traps, Shannon traps and aspiration in resting places. The identification was performed according to Young & Duncan (1994) and drawings were made using a microscope with camara lucida . Abnormalities in the cibarium of Lu. evansi were detected in 4 (0.12%) females of the 3,477 adults that were studied. Lutzomyia evansi can have uncommon morphological variants associated with an increase in the number of teeth in the cibarium and their arrangement, which may lead to errors in the taxonomic identification of anomalous specimens. The study of such deformities can serve to avoid taxonomic identification errors.

  5. A importância do xenodiagnóstico artifical no diagnóstico da parasitemia pelo Trypanosoma cruzi em pacientes imunocomprometidos

    OpenAIRE

    BRAZ, Lúcia Maria Almeida; AMATO NETO, Vicente; CARIGNANI, Fábio Luiz; MARCHI, Cláudia Regina de

    2001-01-01

    Trypanosoma cruzi parasitemia observed in immunocompromised patients (transplant or positive HIV) occurred more frequently by the artificial xenodiagnosis method (10/38) compared with hemoculture (2/38), given the same quantity of blood. Other ways of diagnosis, like mice inoculation (5/38), QBC and buffy coat (2/38), were evaluated also. This result showed the importance of the artificial xenodiagnosis. The other techniques increased only one more patient positive.A demonstracão da parasitem...

  6. Reinfecções com cepas do Trypanosoma cruzi de diferentes biodemas como fator agravante da miocardite e miosite em camundongos

    OpenAIRE

    Andrade, Sonia Gumes; Campos, Rozália Figueira; Sobral, Karina Souza Castro; Magalhães, Juracy Barbosa; Guedes, Ricardo S. Pereira; Guerreiro, Marcos Lázaro

    2006-01-01

    Reinfections with Trypanosoma cruzi in patients from endemic areas have been claimed to be an aggravation factor of cardiac manifestations in Chagas' disease. In the present study, the influence of triple infections with strains of different biodemes, on cardiac and skeletal muscle lesions was experimentally tested. Fifty eight mice chronically infected with the Colombian strain (Biodeme Type III) were successively reinfected as follows: 1st group - reinfected with 21 SF strain (Type II) foll...

  7. Adaptation of Trypanosoma brucei to gradual loss of kinetoplast DNA: Trypanosoma equiperdum and Trypanosoma evansi are petite mutants of T. brucei

    Czech Academy of Sciences Publication Activity Database

    Lai, De Hua; Hashimi, Hassan; Lun, Z.-R.; Ayala, F. J.; Lukeš, Julius

    2008-01-01

    Roč. 105, č. 6 (2008), s. 1999-2004 ISSN 0027-8424 R&D Projects: GA AV ČR IAA500960705; GA MŠk LC07032; GA MŠk 2B06129; GA ČR GA204/06/1558 Institutional research plan: CEZ:AV0Z60220518 Keywords : RNA editing * surra * dourine * mitochondrion * Protozoa Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 9.380, year: 2008

  8. Presencia en Isla Fuerte, Bolívar de Lutzomyia evansi vector de leishmaniosis visceral Presense of lutzomyia evansi vector of visceral leishmaniosis in Isla Fuerte, Colombia

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    Ivan Darío Vélez

    1994-01-01

    Full Text Available Se hizo un Inventario de fauna flebotomínea en Isla Fuerte, Bolívar, costa caribe colombiana. Se demostró por primera vez en dicha Isla la presencia de Lu. evansi, Lu. gomezi y Lu. trinidadensis. La presencia de Lu. Evansi (91.7% de las 73 capturas, vector principal de la leishmaniosis visceral en la costa caribe colombiana, convierte a Isla Fuerte en una zona de riesgo potencial de transmisión de leishmaniosis visceral.

    An inventory was made of phiebotomidae fauna in Isla Fuerte, Bolívar, on the caribbean colombian coast. The presence of Lu. evansi was demonstrated for the first time in that island and this species constituted 91.7% of 73 captures. Therefore the island becomes a potential risk for transmission of visceralleish. maniosis since Lu. evansi its main vector.

  9. Comparative vectorial efficiency of Lutzomyia evansi and Lu. longipalpis for transmitting Leishmania chagasi.

    Science.gov (United States)

    Montoya-Lerma, J; Cadena, H; Oviedo, M; Ready, P D; Barazarte, R; Travi, B L; Lane, R P

    2003-01-01

    The infection rates and development of Leishmania chagasi in two sandfly species, Lutzomyia evansi and Lutzomyia longipalpis, were evaluated under natural and experimental conditions. Natural infection rates of Lu. evansi in San Andrés de Sotavento (Colombia) and Montañas de Peraza (Venezuela) (0.05 and 0.2%, respectively) were similar to those previously recorded for this species in Colombia and Venezuela and for Lu. longipalpis in many foci of American Visceral Leishmaniasis (AVL). Both sand fly species were able to support the development of two Colombian strains of L. chagasi experimentally acquired from dogs, hamsters or membrane feeders. However, the experimental infection rates and the sequence of parasite development in the guts of these sand flies revealed that parasite colonisation, differentiation, migration and attachment were more frequent and uniform in Lu. longipalpis than in Lu. evansi. This is consistent with a more recent association between L. chagasi and Lu. evansi, and these results might help to explain the irregularity of AVL outbreaks in foci where Lu. evansi has been reported as the sole vector. Copyright 2002 Elsevier Science B.V.

  10. Comportamento das cepas Y e Peruana do Trypanosoma cruzi no camundongo, após passagem em diferentes meios Behavior of the Y and Peruvian strains of Trypanasoma cruzi in mice, ofter passage through different media

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    Juracy B. Magalhães

    1985-03-01

    Full Text Available Com o objetivo de verificar se o comportamento morfobiológico e histopalógico de cerpa do Trypanosoma cruzi é mantido após modificações no seu meio de manutenção e multiplicação, foram estudados oito grupos de infecção experimental em camundongos com as cepas Y e Peruana, após manutenção nas seguintes condições cultura acelular em meio de Warren, criopreservação em Nitrogênio líquido durante trinta dias, passagem em triatomíneos e passagem em camundongos. Os parâmetros avaliados foram: parasitemia, mortalidade, sobrevida, morfologiaq dos parasitos no sangue periférico, tropismo tíssular e lesões histopatológicoas. Tanto com a cepa Y como Peruana, cada grupo experimental foi dividido em dois subgrupos de acordo com a dose de inóculo, sendo um inoculado com 10.000 e outro com 50.000 formas tripomastigotas, menos o inoculado com formas de triatomíneos em que o inóculo foi apenas com 10.000 tripomastigotas. Observou-se na infecção pela cepa Y, retardo na evolução da parasitemia nos inoculados com formas de cultura e atenuação de virulência com o inóculo de 10.000 formas. Os caracteres básicos da cepa foram mantidos com predominância de macrofagotropismo na fase inicial da infecção e miotropismo nas fases tardias,predominância de forma delgadas e elevada patogenicidade, com 100% de mortalidade embora com variação nos periodos de sobrevida. Na infecção pela cepa Peruana observou-se também retardo da evolução da parasitemia com o inóculo de 10.000 formas provenientes de triatomíneos, de cultura e de criopreservação. Entretanto, as características morfológicas, o tropismo tissular e a patogenicidade foram mantidos.The behavior of two strains of Trypanosoma cruzi (Y and Peruvian strains in experimental mouse infection, after being passed through different conditions of maintainance and cultivation was studied. The conditions were: Warren's acellular culture medium, cryopreservation in liquid

  11. Trypanosoma equiperdum Low Molecular Weight Proteins As Candidates for Specific Serological Diagnosis of Dourine

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    Mirella Luciani

    2018-03-01

    Full Text Available The diagnosis of dourine can be difficult because the clinical signs of this disease in horses are similar to those of surra, caused by Trypanosoma evansi. Moreover, T. equiperdum and T. evansi are closely related and, so far, they cannot be distinguished using serological tests. In a previous work, the T. equiperdum protein pattern recognized by antibodies from dourine-infected horses and the humoral immune response kinetics were investigated by immunoblotting assay; a total of 20 sera from naturally and experimentally infected horses and from healthy animals were tested. Immunoblotting analysis showed that antibodies from infected horses specifically bind T. equiperdum low molecular weight proteins (from 16 to 35 kDa, which are not recognized by antibodies from uninfected horses. In this work, we tested other 615 sera (7 from naturally infected horses and 608 sera from healthy horses and donkeys: results confirmed the data obtained previously. In addition, six SDS-PAGE bands with molecular weight ranging from 10 to 37 kDa were analyzed by mass spectrometry, in order to identify immunogenic proteins that could be used as biomarkers for the diagnosis of dourine. A total of 167 proteins were identified. Among them, 37 were found unique for T. equiperdum. Twenty-four of them could represent possible candidate diagnostic antigens for the development of serological tests specific for T. equiperdum.

  12. Biological aspects of the DM28C clone of Trypanosoma cruzi after metacylogenesis in chemically defined media Aspectos biológicos do clone Dm 28c de Trypanosoma cruzi após metaciclogênese em meio quimicamente definido

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    Victor T. Contreras

    1988-03-01

    Full Text Available The biological characterization of the Trypanosoma cruzi clone Dm 28c in terms of its growth in LIT medium, cell-cycle, infectivity to mice and interaction with professional and non-professional phagocytic cells shows that it behaves as a bona fide T. cruzi representant. The biological properties of this myotropic clone do not change according to the origin of the trypomastigote forms (i. e., from triatomines, infected mice, cell-culture or from the chemically defined TAUP and TAU3AAG media. In addition Dm 28c metacyclic trypomastigotes from TAU3AAG medium display a high infectivity level to fibroblasts and muscle cells. Experiments on binding of cationized ferritin to trypomastigotes surface show the existence of cap-like structures of ferritin in regions near the kinetoplast. However the nature and role of these anionic sites remain to be determined. The results indicate that metacyclic trypomastigotes from Dm 28c clone obtained under chemically defined conditions reproduce the biological behaviour of T. cruzi, rendering this system very suitable for the study of cell-parasite interactions and for the isolation of trypanosome relevant macromolecules.A caracterização biológica do clone Dm 28c de Trypanosoma cruzi em termos do seu crescimento em meio LIT, ciclo celular, infectividade para camundongos e interação com células fagocíticas profissionais e não-profissionais, mostra que o mesmo comporta-se como um fiel representante da espécie T. cruzi. As propriedades biológicas deste clone miotrópico não mudam de acordo com a proveniência das formas tripomastigotas (i. e., de triatomíneos, de camundongos infectados, de cultura celular ou dos meios quimicamente definidos TAUP e TAU3AAG. Ainda mais, formas tripomastigotas metacíclicas do clone Dm 28c derivado do meio TAU3AAG apresentam um alto grau de infectividade para fibroblastos e células de músculo. Experimentos de ligação de ferritina cationizada à superfície de

  13. Trypanocidal activity of genotoxic concentration of benznidazole on epimastigote forms of Trypanosoma cruzi = Atividade tripanocida da concentração genotóxica do benzonidazol em formas epimastigotas de Trypanosoma cruzi

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    Edilson Nobuyoshi Kaneshima

    2012-10-01

    Full Text Available The genotoxicity of benznidazole at a concentration of 75 µM, used in the treatment of Chagas’ disease, has been recently reported. The present study evaluated the inhibitory effect of benznidazole on the growth of epimastigote forms of T. cruzi I and II by using genotoxic (75 µM and non-genotoxic (50 µM concentrations. To assess the growth rates of T. cruzi strains G2, A2.1A, CL, Y, and 2052, parasites in the epimastigote form were cultured in LIT medium for 192 h at 28ºC, with (50 and 75 µM and without (negative control benznidazole. Benznidazole at both concentrations inhibited all the strains, regardless of genetic group. In the 75 µM concentration, there was a significant decrease in the number of parasites inoculated at T0 after 96 h incubation. The results showed that although genotoxic and non-genotoxic doses of benznidazole inhibit the growth of the epimastigote forms of T. cruzi I and II, only the 75 µM dose seem to indicate a possible trypanocidal effect.O benzonidazol é um medicamento utilizado no tratamento da doença de Chagas, cuja genotoxicidade foi recentemente observada em concentrações a partir de 75 µM. O efeito inibitório do benzonidazol sobre o crescimento de formas epimastigotas de T. cruzi I e II foi avaliado no presente trabalho, utilizando-se concentrações genotóxica (75 µM e não genotóxica (50 µM deste medicamento. Para avaliação da taxa de crescimento das cepas G2, A2.1A, CL, Y e 2052, os parasitos na forma epimastigota foram cultivados em meio LIT, durante 192 horas, à 28 o C, tanto em presença de benzonidazol (50 e 75 µM, quanto em sua ausência (controle negativo. O efeito inibitório do benzonidazol, em ambas concentrações, foi observado para todas as cepas analisadas, independentemente do grupo genético a que pertençam. Na concentração de 75 µM, observou-se após 96 horas de incubação, redução significativa do número de parasitos inoculados no tempo zero (T0. Os resultados

  14. Trypanosoma vivax infection dynamics in a cattle herd maintained in a transition area between Pantanal lowlands and highlands of Mato Grosso do Sul, Brazil Dinâmica de infecção de Trypanosoma vivax em rebanho bovino mantido numa área de transição entre o Pantanal e o planalto de Mato Grosso do Sul

    Directory of Open Access Journals (Sweden)

    Charles F. Martins

    2008-01-01

    Full Text Available Trypanosoma vivax outbreaks in beef cattle in the Pantanal region of Mato Grosso do Sul state, Brazil, causes relevant economical impact due to weight loss, abortion and mortality. Cattle moved from the Pantanal to adjacent areas of this ecosystem for breeding and fattening is a common feature. Therefore an epidemiological study on breeding cows in the transition area between Pantanal lowland and adjacent highlands of Mato Grosso do Sul was performed to determine the T. vivax infection dynamics and outbreak risk. Three experimental groups were formed: Group 1 consisted of cows parasitologically negative by the Woo test and in the enzyme-linked immunosorbent assay for T. vivax antibody detection (Tv-ELISA-Ab; Group 2 parasitologically negative and positive in the Tv-ELISA-Ab; and in Group 3 cows were parasitologically positive and with positive reactions in the Tv-ELISA-Ab. During 24 months, the cows' dislodgment between the above established groups was monitored by Woo test and Tv-ELISA-Ab exams. The tabanid population was also monitored and the highest number occurred during the rainy season. Although parasitemias were detected only in the first four samplings of the experimental period, the cows could be considered as trypanotolerant, because no clinical signs were observed. Despite the higher T. vivax incidence during the dry season, no disease symptoms were seen. Even though T. vivax epidemiological situation in the herd was characterized as endemic with seasonal variation, the probability of outbreaks was null within the conditions of the study.Surtos de Trypanosoma vivax em bovinos de corte do Pantanal foram responsáveis por relevante impacto econômico, devido a perda de peso, abortos e mortalidade. Um manejo comum é o deslocamento de bovinos do Pantanal baixo para áreas adjacentes desse ecosistema para reprodução e engorda. Por essa razão, foi efetuado um estudo epidemiológico em rebanho de vacas movidas para uma área de transi

  15. Aspectos clínicos, epidemiológicos e patológicos da infecção natural em bovinos por Trypanosoma vivax na Paraíba Clinical, epidemiological and pathological signs of natural infection in cattle by Trypanosoma vivax in Paraíba, Brazil

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    Jael S. Batista

    2008-01-01

    Full Text Available Descrevem-se dois surtos de tripanossomíase por Trypanosoma vivax em bovinos, ocorridos em dois estabelecimentos do alto sertão da Paraíba. Os sinais clínicos, a patologia e a epidemiologia da doença foram estudados no período de maio de 2005 a novembro de 2006.T. vivax foi identificado em esfregaços da capa leucocitária e mediante a reação em cadeia da polimerase (PCR. Os animais afetados apresentaram anorexia, depressão, febre, anemia, perda de peso, redução da produção leiteira, cegueira transitória, aborto e sinais nervosos caracterizados por incoordenação motora, salivação, opistótono, nistagno, tetania e bruxismo. Todos os animais que apresentaram sintomatologia nervosa morreram. As alterações macroscópicas observadas em um bovino submetido à necropsia foram aumento de volume dos linfonodos, atrofia serosa dos depósitos de gordura, aumento de volume do baço com evidência da polpa branca, hidropericárdio, além de petéquias e equimoses no epicárdio. Histologicamente havia meningoencefalite. O controle da doença na propriedade com tratamento específico dos casos clínicos com aceturato de diminazene foi eficiente, pois após o tratamento não se verificou mais a presença do parasita em esfregaços sanguíneos nem evidência clínica da enfermidade em até 2 meses após o início do surto. Os fatores epidemiológicos favoráveis à ocorrência dos surtos foram a abundância de vetores mecânicos, como tabanídeos e Stomozys spp., e a entrada, no rebanho, de animais oriundos de propriedades onde ocorreu a doença em questão. Sugere-se que o semi-árido do Nordeste, devido a períodos prolongados de secas e altas temperaturas, é região de instabilidade enzoótica para a tripanossomíase, em conseqüência, provavelmente, ao ambiente desfavorável para o desenvolvimento de vetores durante a maior parte do ano.Two outbreaks of trypanosomiasis by Trypanosoma vivax, reported in cattle, occurred on two farms

  16. Transmissão do Trypanosoma cruzi em três gerações de Cavia porcellus sem a participação de triatomíneos

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    Ítalo A. Sherlock

    1976-02-01

    Full Text Available Foi verificada a transmissão sucessiva do T. cruzi em três gerações da cobaia Cavia porcellus sem a participação de triatomíneos. Embora não fosse determinado qual das vias, se placentária, leite, excreções ou contágio direto pelo qual o protozoário foi transmitido para os descendentes, chama-se atenção para a importância da manutenção de reservatórios da Doença de Chagas, mesmo na ausência de vetores invertebrados.The sucessive transmission of Trypanosoma cruzi among three generations of the guinea pig Cavia porcellus without the participation of triatomine bugs is verified. Although the mode of transmission, such as congenital, infected milk or other excretion or direct contagion was not defined, this maybe of importance in natural maintenance of reservoirs of T. cruzi without the invertebrate vectors.

  17. Molecular identification and phylogenetic analysis of Dipetalonema evansi (LEWIS, 1882) in camels (Camelus dromedarius) of Iran.

    Science.gov (United States)

    Sazmand, Alireza; Eigner, Barbara; Mirzaei, Mohammad; Hekmatimoghaddam, Seyedhossein; Harl, Josef; Duscher, Georg Gerhard; Fuehrer, Hans-Peter; Joachim, Anja

    2016-04-01

    Despite the economic importance of camels, the parasites that affect them have not received adequate attention so far and molecular studies are scarce compared to other livestock. In this study, we characterized peripheral blood microfilariae in 200 healthy one-humped camels (Camelus dromedarius) from south-east Iran by microscopy and molecular tools to receive a more detailed insight into prevalence and species that affect them. Moreover, adult specimens of the filarial nematode Dipetalonema evansi were collected from the carcass of an infected animal. Microscopic examination was performed on Giemsa-stained blood smears, and blood was also spotted on Whatman FTA(®) cards for DNA analysis. Genomic DNA was extracted, and PCR was carried out for the detection of filaroid helminths, followed by sequence analysis of positive samples. Four samples were positive for microfilariae by microscopy, while 16 animals (8 %) were positive by PCR. Sequence analysis revealed D. evansi in all cases. Phylogenetic analysis of a cytochrome C oxidase subunit I (COI) sequence of filaroid nematodes showed that most species in a single genus cluster in the same clade; however, D. evansi and D. gracile are not monophyletic and branch rather at the base of the tree. Further studies on the life cycle of D. evansi, specifically the identification of intermediate host(s), have become feasible with the provision of the first specific COI sequences in this study.

  18. Drought-Stressed Tomato Plants Trigger Bottom-Up Effects on the Invasive Tetranychus evansi.

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    Miguel G Ximénez-Embún

    Full Text Available Climate change will bring more drought periods that will have an impact on the irrigation practices of some crops like tomato, from standard water regime to deficit irrigation. This will promote changes in plant metabolism and alter their interactions with biotic stressors. We have tested if mild or moderate drought-stressed tomato plants (simulating deficit irrigation have an effect on the biological traits of the invasive tomato red spider mite, Tetranychus evansi. Our data reveal that T evansi caused more leaf damage to drought-stressed tomato plants (≥1.5 fold for both drought scenarios. Mite performance was also enhanced, as revealed by significant increases of eggs laid (≥2 fold at 4 days post infestation (dpi, and of mobile forms (≥2 fold and 1.5 fold for moderate and mild drought, respectively at 10 dpi. The levels of several essential amino acids (histidine, isoleucine, leucine, tyrosine, valine and free sugars in tomato leaves were significantly induced by drought in combination with mites. The non-essential amino acid proline was also strongly induced, stimulating mite feeding and egg laying when added to tomato leaf disks at levels equivalent to that estimated on drought-infested tomato plants at 10 dpi. Tomato plant defense proteins were also affected by drought and/or mite infestation, but T. evansi was capable of circumventing their potential adverse effects. Altogether, our data indicate that significant increases of available free sugars and essential amino acids, jointly with their phagostimulant effect, created a favorable environment for a better T. evansi performance on drought-stressed tomato leaves. Thus, drought-stressed tomato plants, even at mild levels, may be more prone to T evansi outbreaks in a climate change scenario, which might negatively affect tomato production on area-wide scales.

  19. Taxonomy Icon Data: Trypanosoma brucei [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Trypanosoma brucei Trypanosoma brucei Trypanosoma_brucei_L.png Trypanosoma_brucei_NL.png Trypanoso...ma_brucei_S.png Trypanosoma_brucei_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Trypanoso...ma+brucei&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Trypanosoma+brucei&t=NL http://bioscie...ncedbc.jp/taxonomy_icon/icon.cgi?i=Trypanosoma+brucei&t=S http://biosciencedbc.jp.../taxonomy_icon/icon.cgi?i=Trypanosoma+brucei&t=NS http://togodb.biosciencedbc.jp/togodb/view/taxonomy_icon_comment_en?species_id=121 ...

  20. Aspectos do ciclo silvestre do Trypanosoma cruzi em regiões de cerrado (Município de Formosa, Estado de Goiás Aspects of the sylvatic cycle of Trypanosoma cruzi in the region of cerrado (Formosa municipality, State of Goias

    Directory of Open Access Journals (Sweden)

    D. A. Mello

    1981-09-01

    Full Text Available Neste trabalho estão apresentados resultados de estudos sobre roedores, marsupiais e triatomíneos do norte do municipio de Formosa,Estado de Goiás, e sua importância no ciclo silvestre do T.cruzi. A região estudada esta localizada do ponto de vista geográfico, na "Provincia do Cerrado". Foram coletados 963 roedores, 11 marsupiais e 766 triatomíneos silvestres. O índice de infecção pelo T. cruzi entre os roedores foi de 0,1% e entre os marsupiais 36,3%, enquanto todos os triatomíneos estavam negativos. Face aos aspectos ecológicos estudados, discute-se o papel desempenhado por roedores e marsupiais na manutenção e circulação do T. cruzi em ambiente silvestre. Alguns aspectos epidemiológicos no ambiente doméstico foram também abordados.Studies were carried out on the role of rodents, marsupials and triatoma bugs in the wild cycle of Trypanosoma cruzi. The area studied, located in the county of formosa, State of Goiás, Brasil, belongs to the "Província do Cerrado". The following animals were collected and examined: 963 rodents, 11 marsupials and 766 wild triatomid bugs. The infection rates for T. cruzi were as follow: 36.3% for the marsupials, 0.1% for the rodents, while all the triatomids were negative. The role of the collected mammals in the maintenance and circulation of T. cruzi in the wild environment is discussed. In addition, some epidemiological aspects of the domestic environment were also studied.

  1. Feeding sources and trypanosome infection index of Rhodnius pallescens in a Chagas disease endemic area of Amador County, Panama Fontes de alimentação de R. pallescens e índice de infecção por Trypanosoma em área endêmica da doença de Chagas em Amador, região central do Panamá

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    Vanessa Pineda

    2008-04-01

    Full Text Available The sylvatic triatomine Rhodnius pallescens is considered to be the most important and widespread vector of Trypanosoma cruzi and Trypanosoma rangeli in Panama. However, its behavior and biological characteristics have only been partially investigated. Thus, to achieve sustainable and efficient control over Chagas disease in Panama, a better understanding of the ecology and biology of R. pallescens is essential. In this study we evaluated R. pallescens host feeding sources using a dot-blot assay, and the trypanosome infection index by PCR analysis in a Chagas disease endemic area of central Panama. It was found that in peridomestic palm trees, 20.3% of the examined bugs had fed on opossums (Didelphis marsupialis. However, we observed an increased anthropophagy (25.4% for those bugs collected inside houses. Considering the domestic and peridomestic habitats as a whole, the proportion of collected R. pallescens infected with trypanosomes was 87.4%. In the two habitats the predominant infection was with T. cruzi (80-90%. Between 47-51% of the analyzed triatomines were infected with T. rangeli. Mixed infections (40-51% were also detected. These findings provide a better basis for the implementation of a rational control and surveillance program for Chagas disease in regions where R. pallescens is endemic.O triatomíneo silvestre Rhodnius pallescens é considerado o mais importante vetor do Trypanosoma cruzi e Trypanosoma rangeli no Panamá. Entretanto, seu comportamento e características biológicas são pouco estudados. Para controlar a doença de Chagas no Panamá é necessário melhorar a compreensão dos aspectos eco-biológicos do R. pallescens. Neste estudo, investigaram-se as fontes de alimentação de R. pallescens usando dot-blot e o índice de infecção por Trypanosoma por metodologia molecular, em área endêmica da doença de Chagas na região central do Panamá. Foi observado que 20,3% dos barbeiros coletados em palmeiras peridom

  2. Meningoencefalites toxoplásmica e chagásica em pacientes com infecção pelo vírus da imunodeficiência humana: diagnóstico diferencial anatomopatológico e tomográfico Meningoencephalitis due to Toxoplasma gondii and Trypanosoma cruzi in patients with HIV infection. Diferencial diagnosis of pathologic and tomographic findings

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    Javier E. Lazo

    1998-04-01

    Full Text Available Em 22 pacientes com sorologia positiva para o vírus da imunodeficiência humana, com ou sem síndrome da imunodeficiência adquirida, dos quais 7 com meningoencefalite toxoplásmica e 15 com meningoencefalite chagásica associadas, procuraram-se dados diferenciais, entre as duas encefalopatias, tanto à anatomia patológica quanto à tomografia computadorizada do crânio. Os resultados observados e os dados da literatura nos permitiram concluir que enquanto na meningoencefalite necrosante focal por Toxoplasma gondii o acometimento dos núcleos da base é freqüente, na meningoencefalite necrosante focal causada pelo Trypanosoma cruzi, lesões dessas estruturas parecem não ocorrer ou ser excepcionais. De outro lado, o acometimento da substância branca parece nitidamente maior na meningoencefalite chagásica que na meningoencefalite toxoplásmica, ao passo que o parasitismo e a hemorragia do tecido nervoso, bem como as lesões das bainhas de mielina são mais freqüentes e intensos na meningoencefalite causada pelo Trypanosoma cruzi que naquela por Toxoplasma.Twenty-two HIV+ patients with encephalitis were studied. Of these, 7 had meningoencephalitis due to Toxoplasma gondii (MT and 15 due to Trypanosoma cruzi (MC. Pathologic and computerized axial tomography (CAT changes were compared. We found that focal necrotizing encephalitis due to Toxoplasma involved the cerebral cortex and the basal ganglia, whereas lesions due to Trypanosoma cruzi were centered in the white matter, sometimes extending into the cortex. Hemorrhages, myelin lesions and organisms were more pronounced in chagasic than in toxoplasmic encephalitis. These findings are consistent with the literature reviewed.

  3. Genome and Phylogenetic Analyses of Trypanosoma evansi Reveal Extensive Similarity to T. brucei and Multiple Independent Origins for Dyskinetoplasty

    Czech Academy of Sciences Publication Activity Database

    Carnes, J.; Anupama, A.; Balmer, O.; Jackson, A.; Lewis, M.; Brown, R.; Cestari, I.; Desquesnes, M.; Gendrin, C.; Hertz-Fowler, C.; Imamura, H.; Ivens, A.; Kořený, Luděk; Lai, De Hua; MacLeod, A.; McDermott, S.; Merritt, C.; Monnerat, S.; Moon, W.; Myler, P.; Phan, I.; Ramasamy, G.; Sivam, D.; Zhao-Rong, L.; Lukeš, Julius; Stuart, K.; Schnaufer, A.

    2015-01-01

    Roč. 9, č. 1 (2015), e3404 ISSN 1935-2735 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 EU Projects: European Commission(XE) 316304 Institutional support: RVO:60077344 Keywords : blood stream forms * kinetoplast DNA * mitochondrial ribosomes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.948, year: 2015

  4. Molecular profiles of Venezuelan isolates of Trypanosoma sp. by random amplified polymorphic DNA method.

    Science.gov (United States)

    Perrone, T M; Gonzatti, M I; Villamizar, G; Escalante, A; Aso, P M

    2009-05-12

    Nine Trypanosoma sp. Venezuelan isolates, initially presumed to be T. evansi, were collected from three different hosts, capybara (Apure state), horse (Apure state) and donkey (Guarico state) and compared by the random amplification polymorphic DNA technique (RAPD). Thirty-one to 46 reproducible fragments were obtained with 12 of the 40 primers that were used. Most of the primers detected molecular profiles with few polymorphisms between the seven horse, capybara and donkey isolates. Quantitative analyses of the RAPD profiles of these isolates revealed a high degree of genetic conservation with similarity coefficients between 85.7% and 98.5%. Ten of the primers generated polymorphic RAPD profiles with two of the three Trypanosoma sp. horse isolates, namely TeAp-N/D1 and TeGu-N/D1. The similarity coefficient between these two isolates and the rest, ranged from 57.9% to 68.4% and the corresponding dendrogram clustered TeAp-N/D1 and Te Gu-N/D1 in a genetically distinct group.

  5. Rearing and Colonization of Lutzomyia evansi (Diptera: Psychodidae, a Vector of Visceral Leishmaniasis in Colombia

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    James Montoya-Lerma

    1998-03-01

    Full Text Available The sandfly Lutzomyia evansi from a focus of visceral leishmaniasis in northern Colombia was reared and maintained under laboratory conditions for five generations. The average time for total development was 41.8 days (range = 35.1- 49.6 at 25 oC and 89-95% of relative humidity. The mean number of eggs laid was lower in laboratory bred females either in pots (13.2 eggs/female or vials (29.9 eggs/female than in wild caught females (33.4 eggs/female. Immature mortality, mainly due to fungal and mite contamination, was higher during the first two instars than in the remaining immature stages. Adults were robust and healthy although difficult to feed on hamster or chick skin membrane. In summary, Lu. evansi is a colonizable species but requires specific conditions.

  6. Rearing and colonization of Lutzomyia evansi (Diptera: Psychodidae), a vector of visceral leishmaniasis in Colombia.

    Science.gov (United States)

    Montoya-Lerma, J; Cadena-Peña, H; Jaramillo-Salazar, C

    1998-01-01

    The sandfly Lutzomyia evansi from a focus of visceral leishmaniasis in northern Columbia was reared and maintained under laboratory conditions for five generations. The average time for total development was 41.9 days (range = 35.1-49.6) at 25 degrees C and 89-95% of relative humidity. The mean number of eggs laid was lower in laboratory bred females either in pots (13.2 eggs/female) or vials (29.9 eggs/female) than in wild caught females (33.4 eggs/female). Immature mortality, mainly due to fungal and mite contamination, was higher during the first two instars than in the remaining immature stages. Adults were robust and healthy although difficult to feed on hamster or chick skin membrane. In summary, Lu. evansi is a colonizable species but requires specific conditions.

  7. Estimación del tiempo de desarrollo de Lutzomyia evansi bajo condiciones experimentales

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    Claudia Martínez Suárez

    2012-01-01

    Full Text Available Objetivo: Estimar el tiempo promedio de desarrollo de Lutzomyia evansi. Materiales y métodos: Se inició una colonia de Lutzomyia evansi con individuos recolectados en la zona urbana de la ciudad de Sincelejo (Colombia. La colonia fue mantenida en el laboratorio durante tres generaciones filiales bajo condiciones experimentales promedio de 26ºC de temperatura y 94% de humedad relativa. Resultados: La duración del desarrollo de Lutzomyia evansi fue de 36 a 45 días. El tiempo requerido para el desarrollo de los huevos fue en promedio de 6,75 días (rango de 6 a 8 días. La duración en promedio de los diferentes estadios larvales fue 5,75 días en larvas de primer estadio (rango de 5 a 8 días, 5,75 días en larvas de segundo estadio (rango de 4 a 7 días, 5 días en larvas de tercer estadio (rango de 4 a 7 días y 7 días en larvas de cuarto estadio (rango de 6 a 8 días. En la fase de pupa, la duración en promedio fue de 9,75 días (rango de 7 a 17 días. Conclusiones: El tiempo promedio requerido para el desarrollo de Lutzomyia evansi, comprendido desde la alimentación sanguínea de la hembra madre hasta la emergencia del adulto, es de 40 días.

  8. Frequency of antibodies to Babesia bigemina, B. bovis, Anaplasma marginale, Trypanosoma vivax and Borrelia burdgorferi in cattle from the northeastern region of the state of Pará, Brazil Freqüência de anticorpos para Babesia bigemina, B. bovis, Anaplasma marginale, Trypanosoma vivax e Borrelia burgdorferi em bovinos do nordeste do Estado do Pará, Brasil

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    Daniel S. Guedes Junior

    2008-06-01

    Full Text Available Babesiosis, anaplasmosis, and trypanosomosis are relevant diseases, potentially causing morbidity in cattle, leading to economic losses. Borreliosis is import as a potential zoonosis. The objective of this study was to determine, by indirect enzyme-linked immunosorbent assay (ELISA, the frequency of seropositive cattle to Babesia bigemina, B. bovis, Anaplasma marginale, Trypanosoma vivax and Borrelia burgdorferi in cattle from the Northeastern region of Pará, Brazil. Sera samples from 246 female adult cattle from municipalities of Castanhal and São Miguel do Guamá were used. Crude antigens ELISAs were used to detect antibodies to all agents, except to A. marginale, to which an indirect ELISA with recombinant major surface 1a protein (MSP1a antigen was used. Overall frequencies of seropositive animals were: B. bigemina - 99.2%; B. bovis - 98.8%; A. marginale - 68.3%; T. vivax - 93.1% and B. burgdorferi - 54.9%. The frequencies of seropositive cattle to B. bovis and B. bigemina suggest a high rate of transmission of these organisms by tick in the studied region, which can be classified as enzootically stable to these hemoprotozoans. The low frequency of seropositive cattle to A. marginale may be attributed to a lower sensitivity of the recombinant antigen ELISA utilized or a distinct rate of inoculation of this rickettsia by ticks, as compared with Babesia sp. transmission. The high frequency of seropositive cattle to T. vivax indicates that this hemoprotozoan is prevalent in herds from the Northeastern region of Pará. The rate of animal that showed homologues antibodies to B. burgdorferi indicates the presence of the tickborne spirochaetal agent in the cattle population in the studied region.A babesiose, a anaplasmose e a tripanossomose são enfermidades relevantes, potencialmente causadoras de morbidade em bovinos, levando a perdas econômicas. A borreliose assume importância como zoonose potencial. O objetivo desse estudo foi determinar

  9. Utilização, em politransfundidos, da pesquisa de anticorpos igm anti-trypanosoma cruzi e anti-toxoplasma gondii para detectar infecções pós-transfusionais recentes IgM Trypanosoma cruzi and Toxoplasma gondii antibodies in the detection of recent transfusion-transmitted infections

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    Vicente Amato Neto

    1984-04-01

    Full Text Available Consideram os Autores que a pesquisa de anticorpos IgM no soro é tática capaz de revelar recentes infecções pós-transfusionais. Por isso, decidiram usar esse tipo de mensuração relativamente a grupo constituído por 101 politrans-fundidos, tendo abordado especificamente as aquisições de doença de Chagas e toxoplasmose. Através da investigação que realizaram, só em duas oportunidades encontraram anticorpos IgM anti-Trypanosoma cruzi ou anti-Toxoplasma gondii e, portanto, não evidenciaram expressivo panorama tradutor de processos há pouco tempo contraídos, como ainda, por meio de anticorpos IgG não identificaram números expressivos de pessoas com essas protozooses. No entanto, detectaram a expressiva taxa de 4,9% de casos de doença de Chagas muito provavelmente decorrentes da hemoterapia. A despeito da relevância não acentuada dos resultados que obtiveram, julgaram os Autores ser válido estimular a efetivação de outros estudos congêneres e correlatos, aptos a contribuir para aqui-latamento de riscos pertinentes à prática hemoterápica.The Authors have regarded serum IgM antibodies titration as useful in the detection of recent transfusion-transmitted infections. For this reason a group consisting of 101 patients, who had received many blood transfusions, underwent such mensuration in order to reveal recent Chagas'disease and toxoplasmosis acquired infections. Throughout the investigation just two cases have yielded IgM trypanosomal or toxoplasmal antibodies, showing therefore that this sort of titration did not correlate with the real existence of recent acquired infections. On the other hand IgM antibodies in the same patients did not show a considerable incidence of these two protozoan infections. However an expressive rate of 4.9% of Chagas'disease probably due to hemotherapy was found. Although the results this study were not very relevant, the Authors still have in mind that further similar investigations should be

  10. Estudos sôbre reservatórios e vectores silvestres do Trypanosoma cruzi. XXIV. Variação dos dados biométricos obtidos em amostras do T. cruzi isolados de casos humanos da Doença de Chagas

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    Francisco Ferriolli Filho

    1968-02-01

    Full Text Available Estudo biométrico de 10 amostras de Trypanosoma cruzi isoladas de casos humanos da doença de CHAGAS, nove mantidas em camundongos brancos jovens e uma mantida em ratos brancos jovens, mostrou a existência de grandes variações amostrais. Assim os valores do comprimento total médio das diferentes amostras variaram entre 16,3μ e 21,8μ., enquanto os valores do índice nuclear médio oscilaram entre 0,93 e 1,52. Êstes resultados ampliam os limites de variações amostrais até agora observadas no T. cruzi, especialmente os que se referem ao índice nuclear médio.

  11. Structural differences in gut bacteria communities in developmental stages of natural populations of Lutzomyia evansi from Colombia's Caribbean coast.

    Science.gov (United States)

    Vivero, Rafael José; Jaramillo, Natalia Gil; Cadavid-Restrepo, Gloria; Soto, Sandra I Uribe; Herrera, Claudia Ximena Moreno

    2016-09-13

    Lutzomyia evansi, a phlebotomine insect endemic to Colombia's Caribbean coast, is considered to be the main vector of visceral and cutaneous leishmaniasis in the region. Although insects of this species can harbor pathogenic and non-pathogenic microorganisms in their intestinal microbiota, there is little information available about the diversity of gut bacteria present in Lutzomyia evansi. In this study, conventional microbiological methods and molecular tools were used to assess the composition of bacterial communities associated with Lutzomyia evansi guts in immature and adult stages of natural populations from the department of Sucre (Caribbean coast of Colombia). Sand flies were collected from two locations (peri-urban and jungle biotype) in the Department of Sucre (Caribbean coast of Colombia). A total of 752 Lutzomyia evansi intestines were dissected. In this study, 125 bacterial strains were isolated from different culture media (LB Agar, MacConkey Agar). Different methods were used for bacterial identification, including ribosomal intergenic spacer analysis (RISA) and analysis of the 16S rRNA and gyrB gene sequences. The genetic profiles of the bacterial populations were generated and temporal temperature gradient gel electrophoresis (TTGE) was used to compare them with total gut DNA. We also used PCR and DNA sequence analysis to determine the presence of Wolbachia endosymbiont bacteria and Leishmania parasites. The culture-dependent technique showed that the dominant intestinal bacteria isolated belong to Acinetobacter, Enterobacter, Pseudomonas, Ochrobactrum, Shinella and Paenibacillus in the larval stage; Lysobacter, Microbacterium, Streptomyces, Bacillus and Rummeliibacillus in the pupal stage; and Staphylococcus, Streptomyces, Brevibacterium, Acinetobacter, Enterobacter and Pantoea in the adult stage. Statistical analysis revealed significant differences between the fingerprint patterns of the PCR-TTGE bands in bacterial communities from immature and

  12. Phylogenetic position of the giant anuran trypanosomes Trypanosoma chattoni, Trypanosoma fallisi, Trypanosoma mega, Trypanosoma neveulemairei, and Trypanosoma ranarum inferred from 18S rRNA gene sequences.

    Science.gov (United States)

    Martin, Donald S; Wright, André-Denis G; Barta, John R; Desser, Sherwin S

    2002-06-01

    Phylogenetic relationships within the kinetoplastid flagellates were inferred from comparisons of small-subunit ribosomal RNA gene sequences. These included 5 new gene sequences, Trypanosoma fallisi (2,239 bp), Trypanosoma chattoni (2,180 bp), Trypanosoma mega (2,211 bp), Trypanosoma neveulemairei (2,197 bp), and Trypanosoma ranarum (2,203 bp). Trees produced using maximum-parsimony and distance-matrix methods (least-squares, neighbor-joining, and maximum-likelihood), supported by strong bootstrap and quartet-puzzle analyses, indicated that the trypanosomes are a monophyletic group that divides into 2 major lineages, the salivarian trypanosomes and the nonsalivarian trypanosomes. The nonsalivarian trypanosomes further divide into 2 lineages, 1 containing trypanosomes of birds, mammals, and reptiles and the other containing trypanosomes of fish, reptiles, and anurans. Among the giant trypanosomes, T. chattoni is clearly shown to be distantly related to all the other anuran trypanosome species. Trypanosoma mega is closely associated with T. fallisi and T. ranarum, whereas T. neveulemairei and Trypanosoma rotatorium are sister taxa. The branching order of the anuran trypanosomes suggests that some toad trypanosomes may have evolved by host switching from frogs to toads.

  13. Reproductive performance of seven strains of the tomato red spider mite Tetranychus evansi (Acari: Tetranychidae) at five temperatures

    DEFF Research Database (Denmark)

    Gotoh, T.; Sugimoto, N.; Pallini, A.

    2010-01-01

    The tomato red spider mite Tetranychus evansi Baker et Pritchard occurs on solanaceous plants, and causes serious damage to a variety of crops in Africa and Europe. In 2001 this species was also found in Japan, on nightshade (Solanum nigrum L.), and its invasion to solanaceous of agricultural imp...

  14. A proline racemase based PCR for identification of Trypanosoma vivax in cattle blood.

    Directory of Open Access Journals (Sweden)

    Regassa Fikru

    Full Text Available A study was conducted to develop a Trypanosoma vivax (T. vivax specific PCR based on the T. vivax proline racemase (TvPRAC gene. Forward and reverse primers were designed that bind at 764-783 bp and 983-1002 bp of the gene. To assess its specificity, TvPRAC PCR was conducted on DNA extracted from different haemotropic pathogens: T. vivax from Nigeria, Ethiopia and Venezuela, T. congolense Savannah type, T. brucei brucei, T. evansi, T. equiperdum, T. theileri, Theileria parva, Anaplasma marginale, Babesia bovis and Babesia bigemina and from bovine, goat, mouse, camel and human blood. The analytical sensitivity of the TvPRAC PCR was compared with that of the ITS-1 PCR and the 18S PCR-RFLP on a dilution series of T. vivax DNA in water. The diagnostic performance of the three PCRs was compared on 411 Ethiopian bovine blood specimens collected in a former study. TvPRAC PCR proved to be fully specific for T. vivax, irrespective of its geographical origin. Its analytical sensitivity was lower than that of ITS-1 PCR. On these bovine specimens, TvPRAC PCR detected 8.3% T. vivax infections while ITS-1 PCR and 18S PCR-RFLP detected respectively 22.6 and 6.1% T. vivax infections. The study demonstrates that a proline racemase based PCR could be used, preferably in combination with ITS-1 PCR, as a species-specific diagnostic test for T. vivax infections worldwide.

  15. PRESENCIA DE Wolbachia y Leishmania EN UNA POBLACION DE Lutzomyia evansi PRESENTE EN LA COSTA CARIBE DE COLOMBIA

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    Rafael J. Vivero-Gómez

    2016-07-01

    Full Text Available Lutzomyia evansi es importante en salud pública por su participación en la trasmisión de la leishmaniasis visceral y cutánea en la costa caribe de Colombia. Diversos estudios se han desarrollado sobre la poblaciones naturales de Lutzomyia evansi, sin embargo pocos estudios han explorado en profundidad la detección de microorganismos simbióticos (ej. Wolbachia y de manera simultánea la presencia de Leishmania sp.. El endosimbionte Wolbachia ha sido propuesto en la actualidad como control biológico de insectos vectores de diversas enfermedades tropicales. En el presente estudio el ADN de tres especies del género Lutzomyia colectadas en el municipio de Ovejas (Departamento de Sucre fue evaluado para detectar la infección natural por la bacteria Wolbachia y la presencia de parásitos del género Leishmania. El ADN total de 176 individuos adultos y 34 inmaduros (larvas y pupas de Lu. evansi, fue utilizado para evaluar la detección de Wolbachia mediante amplificación por PCR del gen WSP (Proteína Mayor de la Superficie de Wolbachia y la infección por Leishmania mediante amplificación por PCR de segmentos de los genes HPSN70 (Proteína de Choque Térmico. Se encontró un grupo de machos infectado de forma natural por Wolbachia y nueve grupos de hembras con infección natural por Leishmania, todos pertenecientes a Lutzomyia evansi. El análisis filogenético de la secuencia del gen WSP de Wolbachia indica la ubicación de la cepa detectada dentro del supergrupo B (haplogrupo wLeva y su relación con haplotipos previamente reportados de Lutzomyia evansi y Lutzomya dubitans. Una región de 418 pb del gen HSP-70N fue secuenciada y mostró similaridad con secuencias de Leishmania luego de realizar el análisis en BlastN. Se confirma la presencia de Wolbachia en poblaciones silvestres de machos de L. evansi y la infección natural por Leishmania spp. en hembras de la misma especie cuya infección por Wolbachia resulto negativa.

  16. Trypanosoma cruzi: vertebrate and invertebrate cycles in the same mammal host, the opossum Didelphis marsupialis

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    Maria P. Deane

    1984-12-01

    Full Text Available 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.No gambá (Didelphis marsupialis foi observado um ciclo extracelular do Trypanosoma cruzi: o parasita crescia abundantemente no material de secreção acumulado no lumen das glandulas anais de animais criados em cativeiro e infectados por via subcutanea com fezes de triatomineos.

  17. Genetic analysis of a recently detected urban population of Lutzomyia evansi (Diptera: Psychodidae in Colombia

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    Eduar Elías BEJARANO

    2009-01-01

    Full Text Available Lutzomyia evansi (Núñez-Tovar es el insecto transmisor del parásito Leishmania infantum en zonas rurales del norte de Colombia. Con el propósito de establecer el probable origen de una población urbana del vector, detectada en años recientes, se caracterizaron genéticamente ejemplares de Lutzomyia evansi de siete localidades geográficas del Caribe Colombiano. Los flebotomíneos fueron recolectados en ambientes rurales y urbanos de zonas endémicas y no endémicas de leishmaniasis visceral. Dentro del fragmento secuenciado de 315 pb correspondiente al extremo 3’ del gen mitocondrial citocromo b, se encontraron nueve sitios polimórficos, nueve haplotipos nucleotídicos y un solo haplotipo aminoacídico. Las distancias genéticas pareadas entre los haplotipos, estimadas con el modelo de Kimura de dos parámetros, oscilaron entre 0,0032 y 0,0194. El análisis reveló la existencia de una baja variabilidad genética entre especímenes de localidades urbanas y rurales. Varios de los flebotomíneos recolectados en la zona urbana de la ciudad de Sincelejo, departamento de Sucre, donde en años recientes aparecieron casos autóctonos de leishmaniasis visceral, fueron genéticamente similares a los de El Contento, en el cercano departamento de Córdoba, foco rural de la enfermedad. Se discuten las implicaciones epidemiológicas de este hallazgo para la transmisión de Leishmania infantum en el Caribe Colombiano.

  18. Effect of a second bloodmeal on the oesophagus colonization by Leishmania mexicana complex in Lutzomyia evansi (Diptera: Psychodidae

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    Alejandra Vivenes

    2001-04-01

    Full Text Available Migration and colonization of the oesophagus by Leishmania mexicana parasites were enhanced after digestion of a second bloodmeal intake in Lutzomyia evansi. This event has epidemiological significance since it affects the infection susceptibility of this sand fly species, which is a proven vector of L. chagasi in Colombian and Venezuelan visceral leishmaniasis foci. Also, it may explain the host seeking behaviour displayed by some partially bloodfed flies found inside houses.

  19. Variabilidad genética en Lutzomyia ( verrucarum evansi (Núñez-Tovar, 1924, vector de Leishmaniosis visceral americana

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    Charles Porter

    2001-04-01

    Full Text Available

    Lutzomyia evansi (Núñez-Tovar, 1924, Lutzomyia longipalpis
    (Lutz y Neiva, 1912 y Lutzomyia cruzi (Mangabeira, 1938, son los
    vectores de Leishmania infantum Nicolle, 1908, en el neotrópico. Lu. evansi ha sido incriminada como vector en zonas rurales de la Costa Caribe Colombiana, y algunas zonas de Venezuela y Nicaragua. A pesar de que esta especie reviste gran importancia en Salud Pública, no existen a la fecha estudios sobre su variabilidad genética, desconociéndose si existe o no flujo genético entre las poblaciones rurales y urbanas, endémicas y no endémicas de leishmaniosis visceral (LV. Con base en los genes mitocondriales Citocromo b, RNA de transferencia para Serina, subunidades uno y cuatro de la NADH deshidrogenasa, se estudió la variabilidad genética entre las distintas poblaciones de Lu. evansi en la Costa Caribe, incluyendo la población
    geográficamente aislada de Isla Fuerte, y una población de Venezuela.

     

  20. Troglitazone induces differentiation in Trypanosoma brucei

    International Nuclear Information System (INIS)

    Denninger, Viola; Figarella, Katherine; Schoenfeld, Caroline; Brems, Stefanie; Busold, Christian; Lang, Florian; Hoheisel, Joerg; Duszenko, Michael

    2007-01-01

    Trypanosoma brucei, a protozoan parasite causing sleeping sickness, is transmitted by the tsetse fly and undergoes a complex lifecycle including several defined stages within the insect vector and its mammalian host. In the latter, differentiation from the long slender to the short stumpy form is induced by a yet unknown factor of trypanosomal origin. Here we describe that some thiazolidinediones are also able to induce differentiation. In higher eukaryotes, thiazolidinediones are involved in metabolism and differentiation processes mainly by binding to the intracellular receptor peroxisome proliferator activated receptor γ. Our studies focus on the effects of troglitazone on bloodstream form trypanosomes. Differentiation was monitored using mitochondrial markers (membrane potential, succinate dehydrogenase activity, inhibition of oxygen uptake by KCN, amount of cytochrome transcripts), morphological changes (Transmission EM and light microscopy), and transformation experiments (loss of the Variant Surface Glycoprotein coat and increase of dihydroliponamide dehydrogenase activity). To further investigate the mechanisms responsible for these changes, microarray analyses were performed, showing an upregulation of expression site associated gene 8 (ESAG8), a potential differentiation regulator

  1. The development of an enzyme-linked immunosorbent assay for Trypanosoma vivax antibodies and its use in epidemiological surveys

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    Claudio R Madruga

    2006-11-01

    Full Text Available There are data indicating that the distribution of Trypanosoma vivax in the Brazilian territory is expanding with potential to reach other areas, where the vectors are present. The detection of anti-trypanosomal antibodies in serum provides important information of the trypanosomal status in cattle herds. For this reason, an enzyme-linked immunosorbent assay (Tv-ELISA-Ab with crude antigen from one Brazilian isolate of T. vivax was developed and evaluated. The sensitivity and specificity were respectively 97.6 and 96.9%. In the evaluation of cross-reactions, three calves inoculated with T. evansi trypimastigotes blood forms showed optical densities (OD under the cut-off during the whole experimental period, except one at 45 days post-inoculation. With relation to Babesia bovis, B. bigemina, and Anaplasma marginale, which are endemic hemoparasites in the studied area, the cross-reactions were shown to be 5.7, 5.3, and 1.1%, respectively. The first serological survey of Pantanal and state of Pará showed that T. vivax is widespread, although regions within both areas had significantly different prevalences. Therefore, this Tv-ELISA-Ab may be a more appropriate test for epidemiological studies in developing countries because the diagnostic laboratories in most countries may be able to perform an ELISA, which is not true for polymerase chain reaction.

  2. Study of the <em>in Vitroem> Antiplasmodial, Antileishmanial and Antitrypanosomal Activities of Medicinal Plants from Saudi Arabia

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    Nawal M. Al-Musayeib

    2012-09-01

    Full Text Available The present study investigated the <em>in vitroem> antiprotozoal activity of sixteen selected medicinal plants. Plant materials were extracted with methanol and screened <em>in vitroem> against erythrocytic schizonts of <em>Plasmodium falciparumem>, intracellular amastigotes of <em>Leishmania infantum em>and <em>Trypanosoma cruzi em>and free trypomastigotes of<em> T. bruceiem>. Cytotoxic activity was determined against MRC-5 cells to assess selectivity<em>. em>The criterion for activity was an IC50 < 10 µg/mL (4. Antiplasmodial activity was found in the<em> em>extracts of<em> em>>Prosopis julifloraem> and <em>Punica granatumem>. Antileishmanial activity<em> em>against <em>L. infantumem> was demonstrated in <em>Caralluma sinaicaem> and <em>Periploca aphylla.em> Amastigotes of<em> T. cruzi em>were affected by the methanol extract of<em> em>>Albizia lebbeckem>> em>pericarp, <em>Caralluma sinaicaem>,> Periploca aphylla em>and <em>Prosopius julifloraem>. Activity against<em> T. brucei em>was obtained in<em> em>>Prosopis julifloraem>. Cytotoxicity (MRC-5 IC50 < 10 µg/mL and hence non-specific activities were observed for<em> em>>Conocarpus lancifoliusem>.>

  3. Uncertainties in predicting species distributions under climate change: a case study using Tetranychus evansi (Acari: Tetranychidae), a widespread agricultural pest.

    Science.gov (United States)

    Meynard, Christine N; Migeon, Alain; Navajas, Maria

    2013-01-01

    Many species are shifting their distributions due to climate change and to increasing international trade that allows dispersal of individuals across the globe. In the case of agricultural pests, such range shifts may heavily impact agriculture. Species distribution modelling may help to predict potential changes in pest distributions. However, these modelling strategies are subject to large uncertainties coming from different sources. Here we used the case of the tomato red spider mite (Tetranychus evansi), an invasive pest that affects some of the most important agricultural crops worldwide, to show how uncertainty may affect forecasts of the potential range of the species. We explored three aspects of uncertainty: (1) species prevalence; (2) modelling method; and (3) variability in environmental responses between mites belonging to two invasive clades of T. evansi. Consensus techniques were used to forecast the potential range of the species under current and two different climate change scenarios for 2080, and variance between model projections were mapped to identify regions of high uncertainty. We revealed large predictive variations linked to all factors, although prevalence had a greater influence than the statistical model once the best modelling strategies were selected. The major areas threatened under current conditions include tropical countries in South America and Africa, and temperate regions in North America, the Mediterranean basin and Australia. Under future scenarios, the threat shifts towards northern Europe and some other temperate regions in the Americas, whereas tropical regions in Africa present a reduced risk. Analysis of niche overlap suggests that the current differential distribution of mites of the two clades of T. evansi can be partially attributed to environmental niche differentiation. Overall this study shows how consensus strategies and analysis of niche overlap can be used jointly to draw conclusions on invasive threat

  4. Uncertainties in predicting species distributions under climate change: a case study using Tetranychus evansi (Acari: Tetranychidae, a widespread agricultural pest.

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    Christine N Meynard

    Full Text Available Many species are shifting their distributions due to climate change and to increasing international trade that allows dispersal of individuals across the globe. In the case of agricultural pests, such range shifts may heavily impact agriculture. Species distribution modelling may help to predict potential changes in pest distributions. However, these modelling strategies are subject to large uncertainties coming from different sources. Here we used the case of the tomato red spider mite (Tetranychus evansi, an invasive pest that affects some of the most important agricultural crops worldwide, to show how uncertainty may affect forecasts of the potential range of the species. We explored three aspects of uncertainty: (1 species prevalence; (2 modelling method; and (3 variability in environmental responses between mites belonging to two invasive clades of T. evansi. Consensus techniques were used to forecast the potential range of the species under current and two different climate change scenarios for 2080, and variance between model projections were mapped to identify regions of high uncertainty. We revealed large predictive variations linked to all factors, although prevalence had a greater influence than the statistical model once the best modelling strategies were selected. The major areas threatened under current conditions include tropical countries in South America and Africa, and temperate regions in North America, the Mediterranean basin and Australia. Under future scenarios, the threat shifts towards northern Europe and some other temperate regions in the Americas, whereas tropical regions in Africa present a reduced risk. Analysis of niche overlap suggests that the current differential distribution of mites of the two clades of T. evansi can be partially attributed to environmental niche differentiation. Overall this study shows how consensus strategies and analysis of niche overlap can be used jointly to draw conclusions on invasive

  5. Trypanosoma cruzi, cancer and the Cold War Trypanosoma cruzi, câncer e a Guerra Fria

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    Nikolai Krementsov

    2009-07-01

    Full Text Available In the summer of 1946, the international community of cancer researchers was inspired by the announcement that two Soviet scientists, Nina Kliueva and Grigorii Roskin, had discovered anticancer properties in culture extracts made from the South American protozoan, Trypanosoma cruzi, and had produced a preparation - named after its discoverers KR - which showed clear therapeutic effects on cancer patients. Research teams from various countries enthusiastically pursued the promising new line of investigation. The story of the rise and fall of interest in the anticancer properties of T. cruzi in different countries suggests that during the second half of the twentieth century, the Cold War competition between the superpowers played an important role in shaping the research agendas of cancer studies.No verão de 1946, a comunidade internacional que desenvolve pesquisas sobre o câncer, inspirou-se no anúncio de que dois cientistas soviéticos, Nina Kliueva e Grigorii Roskin, descobriram propriedades anticancerígenas em cultura extraída do protozoário existente na América Latina, o Trypanosoma cruzi e produziram um preparado que foi denominado com as iniciais KR - em sua homenagem. Grupos de pesquisadores de diversos países buscaram com entusiasmo as promessas dessa nova linha de investigação. A história da ascensão e queda do interesse nas propriedades anticâncer do T. cruzzi em diferentes países sugere que durante a segunda metade do século 20, a Guerra Fria teve um papel importante na definição das agendas de pesquisas sobre o câncer.

  6. Hematological and serum biochemical aspects associated with a camel (Camelus dromedarius naturally infected by Trypanosoma evansi with severe parasitemia in Semnan, Iran

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    Mahmood Ahmadi-hamedani

    2014-09-01

    Conclusions: Results of the present study revealed that trypanosomosis was present in dromedary camels of Semnan, Iran (infection rate is 4.76% and hemato-biochemical parameters were markedly affected by camel trypanosomosis.

  7. Use of ELISA in the diagnosis of infection and evaluation of treatment with Cymelarsan in camels infected with Trypanosoma evansi in Kenya

    International Nuclear Information System (INIS)

    Olaho-Mukani, W.; Omuse, J.K.; Nyang'ao, J.M.N.; Mutugi, M.W.; Ngaira, J.M.; Luckins, A.G.; Jeffires, P.

    1993-01-01

    A polyclonal based antigen detection enzyme immunoassay (Ag-ELISA) was validated and used for the diagnosis of camel trypanosomiasis in five localities in Kenya. The Ag-ELISA results were correlated with those of parasitological tests, namely, Buffy Coat Technique (BCT) and rodent subinoculation (RI). More animals showed evidence of infection using Ag-ELISA than when using BCT and RI, and showed infection rates ranging from 45.3% to 86.2% in sampled herds, compared with 0.8% to 18% using parasitologial tests. An overall apparent sensitivity of 74% by Ag-ELISA was obtained after screening sera from three camel herds. Higher ELISA values were observed in those herds with the highest rate of patent infection or where drug intervention was not being practised. However, the study revealed that trypanosomiasis was endemic in all the sampled herds and although treatment with quinapyramine sulphate suppressed parasitaemia, the presence of circulating trypanosomal antigens indicated the probable persistence of infection due to resistance to this drug. In experimental camels, the use of Ag-ELISA in evaluating the efficacy of Cymelarsan revealed that in more than 80% of the treated camels there appeared to be cure, characterized by the absence of both parasitaemia and circulating trypanosomal antigens. However, in a few animals relapse in parasitaemia occurred, and in a number of camels, antigenaemia persisted throughout the study period. Treatment on the basis of a positive Ag-ELISA reduced the proportion of Ag-positive animals from 75% to 26% and parasite positive animals were no longer present at the end of the experiment. (author). 13 refs, 4 figs, 3 tabs

  8. 21 CFR 866.3870 - Trypanosoma spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3870 Trypanosoma... consist of antigens and antisera used in serological tests to identify antibodies to Trypanosoma spp. in...

  9. Characterization of plasma menbrane polypeptides of trypanosoma from bats

    OpenAIRE

    Pinho,R. T.; Simone,Giovanni de

    1989-01-01

    Cell surface proteins of Trypanosoma dionisii, Trypanosoma vespertilionis and Trypanosoma sp. (M238) were radiodinated and their distribution both in the detergent-poor (DPP) and dertergent-enriched phase (DRP) was studied using a phase separation technique in Triton X-114 as well as polyacrylamide gel electrophoresis in sodium dodecyl sulphate (SDS-PAGE). Significant differences were observed in the proteins present in the DRP when the three species of trypanosoma were compared. Two major ba...

  10. Anomalías morfológicas en los dientes del cibario de Lutzomyia evansi (Diptera: Psychodidae en el estado Trujillo, Venezuela

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    Yolanda Méndez-de Daboín

    2015-06-01

    Full Text Available Introducción. Lutzomyia evansi es un reconocido vector de Leishmania infantum en Colombia y Venezuela. Objetivo. Describir e ilustrar las anomalías morfológicas presentes en el cibario de hembras de Lu. evansi capturadas en un foco rural de leishmaniasis visceral en Trujillo, Venezuela. Materiales y métodos. Para la captura de los flebótomos se utilizaron tres diferentes métodos (trampa Shannon, trampas de luz del tipo CDC y capturas en reposo. En la identificación taxonómica se siguió la clave de Young & Duncan (1994 y los diseños biológicos se hicieron utilizando un microscopio óptico con cámara clara. Resultados. En 3.477 especímenes de Lu. evansi se detectaron cuatro (0,12 % hembras con diferentes anomalías en el cibario. Conclusión. Algunos especímenes de Lu. evansi pueden presentar anomalías morfológicas relacionadas con aumento del número de los dientes en el cibario y con su disposición. La detección de estas anomalías en poblaciones naturales de Lu. evansi puede evitar dificultades y confusiones en el momento de la identificación taxonómica de los especímenes teratomorfos, reduciendo así el riesgo de incurrir en errores taxonómicos.

  11. Genetic analysis of a recently detected urban population of Lutzomyia evansi (Diptera: Psychodidaein Colombia Análisis genético de una población urbana de Lutzomyia evansi (Diptera: Psychodidae, recientemente detectada en Colombia

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    Eduar Elías Bejarano

    2009-06-01

    Full Text Available Lutzomyia evansi (Núñez-Tovar is the vector of the parasite Leishmania infantum in rural zones of Northern Colombia. An attempt was made to determine the origin of a recently detected urban population of Lutzomyia evansi by genetically characterizing specimens from seven geographically distinct localities in the Colombian Caribbean. Insect specimens were collected in rural and urban environments of areas endemic for visceral leishmaniasis or free of the disease. Nine polymorphic sites, nine nucleotide haplotypes and a single aminoacid haplotype were found within the 315 bp fragment sequenced, corresponding to the 3' end of the cytochrome b mitochondrial gene. Paired genetic distances between the haplotypes, estimated with the Kimura two-parameters model, varied from 0,0032-0,0194. Analysis revealed low genetic variability between specimens from urban and rural localities. Several of the sand flies collected in the city of Sincelejo (department of Sucre, where autochthonous visceral leishmaniasis cases have appeared in recent years, were genetically similar to those of a rural focus of the disease (El Contento, on the neighboring department of Córdoba. The epidemiological implications of this finding for Leishmania infantum transmission in the Colombian Caribbean are discussed.Lutzomyia evansi (Núñez-Tovar es el insecto transmisor del parásito Leishmania infantum en zonas rurales del norte de Colombia. Con el propósito de establecer el probable origen de una población urbana del vector, detectada en años recientes, se caracterizaron genéticamente ejemplares de Lutzomyia evansi de siete localidades geográficas del Caribe Colombiano. Los flebotomíneos fueron recolectados en ambientes rurales y urbanos de zonas endémicas y no endémicas de leishmaniasis visceral. Dentro del fragmento secuenciado de 315 pb correspondiente al extremo 3' del gen mitocondrial citocromo b, se encontraron nueve sitios polimórficos, nueve haplotipos nucleot

  12. A refratariedade das aves ao "Trypanosoma (Schizotrypanum cruzi" II - refratariedade das galinhas desde o nascimento; persistência da refratariedade após Bursectomia; infecções em ovos embrionados The refractory state of birds toward the Trypanosoma (Schizotrypanum cruzi: II - the refractory state begins at hatching and persists after bursectomy, Infections of embryonnated eggs

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    F. Nery-Guimarães

    1972-01-01

    Full Text Available "A refratariedade das galinhas ao T. (S. cruzi, ocorre desde o nascimento e não é eliminada pela bursectomia hormonal. Noventa e oito pintos de 1 a 15 dias de vida (normais ou tratados com testosterona inoculados com o T. (S. cruzi foram negativos. Deste modo, dificilmente a refratariedade poderia ser interpretada como decorrência de um "anticorpo natural", uma vez que a bursectomia provoca uma queda na produção de anticorpos e das gamaglobulinas. Em cerca de 50% de ovos embrionados (normais ou tratados com o hormônio foram vistos flagelados do 4º ao 12º dia de inoculação, observando-se ninhos de amastigotos em alguns embriões. Os pintos nascidos dos mesmos grupos dos ovos examinados e positivos, foram sistematicamente negativos pelo exame do sangue. Um deles sacrificado horas depois de nascido, mostrou amastigotos no coração, mas esses parasitos pareciam degenerados. Provavelmente, se alguns chegam a evoluir para tripomastigotos, estes são destruídos á medida que as células hospedeiras se rompem, e assim jamais são encontrados no sangue circulante.It has already been shown that the refractory state of chickens toward "T. (S. cruzi" appears early at time of hatch. Fifty-four normal newly hatched and inoculated chicks were negative. it has also been verified that this refractory state persists even after hormonal bursectomy (eggs being injected with 2.5 mg of testosterone. Forty-four bursectomized and inoculated newly hatched chicks were negative. If we consider the fact that bursectomy causes a deficiency in the production of antibodies and gammaglobulins, the refractory state seems not to occur on account of a "natural antibody". Inoculations of "T. (S. cruzi" made in 153 eggs (normal or treated with testosterone produced infections of variable intensity in about 50% of them. Although chicks newly hatched from the same groups were always negative. As we have some embryos to be positive until the 21st day of incubation it seems

  13. Estudo parasitológico e anátomo-patológico da fase aguda da doença de Chagas em cães inoculados com duas diferentes cepas do Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Maria Alice Pedreira de Castro

    1985-12-01

    Full Text Available Cães jovens foram infectados com as cepas Y e CL do T. cruzi usando-se como inóculos 107 formas sangüíneas inoculadaspor via intraperitoneal e 2 x 10³ tripomastigotas metacíclicos obtidos do inseto vetor e inoculadospor via conjuntival. As cepas Ye CL induziram nos cães curvas deparasitemia totalmente distintas, confirmando dados parasitológicos obtidos em camundongos e coelhos. Com a cepa CL a parasitemia, com ambos os inóculos, foi gradualmente ascencional ao passo que com Y a parasitemia foi extremamente baixa, irregular e, com freqüência, subpatente. Com ambas as cepas o parasitismo e as lesões predominaram no miocárdio. Entretanto, com a cepa Y a miocardite foi sempre intensa desde as fases mais precoces da infecção, ao passo que com a cepa CL o processo inflamatório tomou-se acentuado somente a partir do 20.° dia. Freqüentemente a intensidade da miocardite observada em alguns animais não guardava relação com a parasitemia; em alguns cães com parasitemia subpatente, nos quais a infecção só foi diagnosticada pelo xenodiagnóstico, a intensidade da miocardite foi comparável àquela observada nos animais com parasitemia patente. Idêntica correlação também não foi assinalada em relação ao parasitismo tissular. Esses achados sugerem a participação de mecanismo imunológicos na gênese das lesões, ainda na fase aguda da infecção.Young dogs were inoculated with T. cruzi Y and CL strains either by intraperitoneal route with 107 blood forms or by ocular route with 2 x 10³ vector-derived trypomastigotes. With both inocula the patterns of parasitemia were significantly different, confirming data previously obtained in experimentally infected mice and rabbits. CL strain induced a gradual ascencional parasitemia whereas with Y the parasitemia was either subpatent or the number of parasites was very low, rapidly declining. Although myocarditis was present in most animals regardless of the strain used, the

  14. Transmissão do Trypanosoma cruzi em três gerações de Cavia porcellus sem a participação de triatomíneos

    Directory of Open Access Journals (Sweden)

    Ítalo A. Sherlock

    1976-02-01

    Full Text Available Foi verificada a transmissão sucessiva do T. cruzi em três gerações da cobaia Cavia porcellus sem a participação de triatomíneos. Embora não fosse determinado qual das vias, se placentária, leite, excreções ou contágio direto pelo qual o protozoário foi transmitido para os descendentes, chama-se atenção para a importância da manutenção de reservatórios da Doença de Chagas, mesmo na ausência de vetores invertebrados.

  15. Characterization of Trypanosoma brucei gambiense stocks isolated ...

    African Journals Online (AJOL)

    Trypanosoma brucei gambiense was isolated twice from each of 23 patients in Côte d'Ivoire. Genetic characterization using RAPD (Random Primed Amplified Polymorphic DNA) showed additional variability within a given isoenzyme profile (zymodeme), confirming that this fingerprinting method has a higher discriminative ...

  16. Antiparasitic activity of diallyl trisulfide (Dasuansu) on human and animal pathogenic protozoa (Trypanosoma sp., Entamoeba histolytica and Giardia lamblia) in vitro.

    Science.gov (United States)

    Lun, Z R; Burri, C; Menzinger, M; Kaminsky, R

    1994-03-01

    Garlic (Allium sativum L.) and one of its major components, allicin, have been known to have antibacterial and antifungal activity for a long time. Diallyl trisulfide is a chemically stable final transformation product of allicin which was synthesized in 1981 in China and used for treatment of bacterial, fungal and parasitic infections in man. The activity of diallyl trisulfide was investigated in several important protozoan parasites in vitro. The IC50 (concentration which inhibits metabolism or growth of parasites by 50%) for Trypanosoma brucei brucei, T.b. rhodesiense, T.b. gambiense, T. evansi, T. congolense and T. equiperdum was in the range of 0.8-5.5 micrograms/ml. IC50 values were 59 micrograms/ml for Entamoeba histolytica and 14 micrograms/ml for Giardia lamblia. The cytotoxicity of the compound was evaluated on two fibroblast cell lines (MASEF, Mastomys natalensis embryo fibroblast and HEFL-12, human embryo fibroblast) in vitro. The maximum tolerated concentration for both cell lines was 25 micrograms/ml. The results indicate that the compound has potential to be used for treatment of several human and animal parasitic diseases.

  17. Trypanosoma brucei gambiense: HMI-9 medium containing methylcellulose and human serum supports the continuous axenic in vitro propagation of the bloodstream form.

    Science.gov (United States)

    Van Reet, N; Pyana, P P; Deborggraeve, S; Büscher, P; Claes, F

    2011-07-01

    Trypanosoma brucei (T.b.) gambiense causes the chronic form of human African trypanosomiasis or sleeping sickness. One of the major problems with studying T.b. gambiense is the difficulty to isolate it from its original host and the difficult adaptation to in vivo and in vitro mass propagation. The objective of this study was to evaluate if an established method for axenic culture of pleomorphic bloodstream form T.b. brucei strains, based on methylcellulose containing HMI-9 medium, also facilitated the continuous in vitro propagation of other bloodstream form Trypanozoon strains, in particular of T.b. gambiense. Bloodstream form trypanosomes from one T.b. brucei, two T.b. rhodesiense, one T. evansi and seven T.b. gambiense strains were isolated from mouse blood and each was concurrently cultivated in liquid and methylcellulose-containing HMI-9 based medium, either with or without additional human serum supplementation, for over 10 consecutive sub passages. Although HMI-9 based medium supplemented with 1.1% (w/v) methylcellulose supported the continuous cultivation of all non-gambiense strains better than liquid media could, the in vitro cultivation of all gambiense strains was only achieved in HMI-9 based medium containing 1.1% (w/v) methylcellulose, 15% (v/v) fetal calf serum and 5% (v/v) heat-inactivated human serum. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Susceptibility of geographically isolated populations of the Tomato red spider mite (Tetranychus evansi Baker & Pritchard to commonly used acaricides on tomato crops in Kenya

    Directory of Open Access Journals (Sweden)

    F. J. Toroitich

    2014-04-01

    Full Text Available Farmers in Kenya continue to raise concerns of difficulty in managing Tetranychus evansi, the most widespread pest species of tomato applying the most commonly used acaricides. This invasive pest species is not only found in Kenya, but in Eastern and Southern Africa, as well as parts of Europe and Asia. In the current study, populations of T. evansi were collected from farms in the four major tomato-growing areas of Kenya (Loitoktok, Kibwezi, Athi-River and Subukia and their susceptibility compared to a laboratory culture (ICIPE that had been maintained for three years without exposure to acaricides. Susceptibility of T. evansi eggs and adults (contact and residual to Brigade (bifenthrin, Dimethoate (dimethoate, Karate (lambdacyhalothrin, Kelthane (dicofol, Omite (propargite and Polytrin (profenofos+ cypermethrin was tested in the laboratory using respective manufacturer’s recommended concentrations. Dimethoate resulted in variable ovicidal mortality while Kelthane, Brigade, Karate, Omite and Polytrin had high mortality across all populations. Similarly, adult contact and residual mortality was lower than that of the other chemicals when exposed to Dimethoate regardless of the location. Furthermore, it also had no residual effect on the mites from ICIPE and Kibwezi. On the other hand, Kelthane was most lethal against the mites from all locations followed by Brigade and Polytrin in that order. Omite caused significantly lower mortality on mites from Subukia while Karate produced variable effects on mites from Kibwezi, Loitoktok and Subukia. The implications of these findings are further discussed.

  19. Dosis diagnóstica y umbral de resistencia de Lutzomyia evansi (Diptera: Psychodidae, a dos insecticidas utilizados en salud pública en Colombia: deltametrina y lambdacihalotrina

    Directory of Open Access Journals (Sweden)

    Caterine HENRIQUEZ

    2009-01-01

    Full Text Available Los insecticidas son una herramienta importante para el control de los insectos transmisores de microorganismos patógenos. El objetivo de este estudio fue determinar la dosis diagnóstica de deltametrina y lambdacihalotrina en el flebotomíneo Lutzomyia evansi (Núñez-Tovar, vector de Leishmania infantum en Colombia. Los insectos se recolectaron en la Estación Experimental de Fauna Silvestre de Colosó, Sucre, un área de reserva natural que no ha sido sometida a presión con insecticidas. Los bioensayos se realizaron en botellas de vidrio, siguiendo el método simplificado de determinación de resistencia del CDC. En los experimentos, se usaron hembras silvestres de L. evansi que fueron expuestas a diferentes concentraciones de los insecticidas por espacio de 80 minutos, tiempo de duración de la prueba. Los valores de dosis diagnóstica hallados fueron 0,00035% para lambdacihalotrina y 0,0007% para deltametrina, con un umbral de resistencia de diez minutos para ambos insecticidas, tiempo en el cual se alcanza una mortalidad del 100%. Los datos de tiempo-mortalidad indican que la lambdacihalotrina tiene un efecto letal sobre L. evansi en menor concentración que la deltametrina, mientras que la última fue menos tóxica.

  20. Detection of Trypanosoma brucei gambiense and T. b. rhodesiense ...

    African Journals Online (AJOL)

    Detection of Trypanosoma brucei gambiense and T. b. rhodesiense in Glossina fuscipes fuscipes ( Diptera: Glossinidae ) and Stomoxys flies using the polymerase chain reaction (PCR) technique in southern Sudan.

  1. Serodiagnosis of bovine trypanosomosis caused by non-tsetse transmitted Trypanosoma (Duttonella) vivax parasites using the soluble form of a Trypanozoon variant surface glycoprotein antigen.

    Science.gov (United States)

    Uzcanga, Graciela L; Pérez-Rojas, Yenis; Camargo, Rocío; Izquier, Adriana; Noda, José A; Chacín, Ronny; Parra, Nereida; Ron, Lenin; Rodríguez-Hidalgo, Richar; Bubis, José

    2016-03-15

    Previous studies have shown that a 64-kDa antigen (p64) that was purified from the Venezuelan TeAp-N/D1 isolate of Trypanosoma (Trypanozoon) equiperdum corresponds to the soluble form of its predominant variant surface glycoprotein (VSG), and exhibited cross-reactivity with Trypanosoma (Duttonella) vivax. The course of experimental acute infections of bovines with T. vivax were followed by measuring whole anti-p64 antibodies and specific anti-p64 IgG and IgM antibodies in animal sera by indirect enzyme-linked immunosorbent assay (ELISA). The value of p64 to diagnose bovine trypanosomosis was also examined using 350 sera from healthy and T. vivax-infected cows living in a trypanosomosis-endemic and enzootic stable area, and 48 sera obtained during a trypanosomosis outbreak. Serological assays showed that ∼ 70-80% of the infected sera contained anti-p64 antibodies, based on the comparative immunodetection of the T. equiperdum clarified antigenic fraction used as a reference test. In the absence of a gold standard, Bayesian analysis for multiple testing estimated a sensitivity and specificity of 71.6% and 98.8%, respectively, for the indirect ELISA using p64 as antigen. An apparent prevalence of 37.7% for bovine trypanosomosis infection was also estimated with a Bayesian approach when the p64 ELISA test was used. Employing blood from acute infected cows, the indirect ELISA response against p64 was contrasted with the microhematocrit centrifuge method and analyses by polymerase chain reaction (PCR) using specific primers targeting the inter-specific length variation of the internal transcribed spacer 1 region of the 18S ribosomal gene. The efficiency of p64 for the detection of anti-trypanosome antibodies in acute infected bovines was also corroborated serologically by comparing its response to that of the Indonesian Trypanosoma evansi Rode Trypanozoon antigen type (RoTat) 1.2 VSG, which possesses high specificity and sensitivity. As expected, PCR was the best

  2. Eco-epidemiological aspects of Trypanosoma cruzi, Trypanosoma rangeli and their vector (Rhodnius pallescens in Panama Generalidades do Trypanosoma cruzi, do Trypanosoma rangeli e do seu vetor (Rhodnius pallescens no Panamá

    Directory of Open Access Journals (Sweden)

    Ana Maria de Vasquez

    2004-08-01

    Full Text Available The eco-epidemiology of T. cruzi infection was investigated in the Eastern border of the Panama Canal in Central Panama. Between 1999 and 2000, 1110 triatomines were collected: 1050 triatomines (94.6% from palm trees, 27 (2.4% from periurban habitats and 33 (3.0% inside houses. All specimens were identified as R. pallescens. There was no evidence of vector domiciliation. Salivary glands from 380 R. pallescens revealed a trypanosome natural infection rate of 7.6%, while rectal ampoule content from 373 triatomines was 45%. Isoenzyme profiles on isolated trypanosomes demonstrated that 85.4% (n = 88 were T. cruzi and 14.6% (n = 15 were T. rangeli. Blood meal analysis from 829 R. pallescens demonstrated a zoophilic vector behavior, with opossums as the preferential blood source. Seroprevalence in human samples from both study sites was less than 2%. Our results demonstrate that T. cruzi survives in the area in balanced association with R. pallescens, and with several different species of mammals in their natural niches. However, the area is an imminent risk of infection for its population, consequently it is important to implement a community educational program regarding disease knowledge and control measures.A epidemiologia da infecção do T. cruzi foi investigada na margem oriental do canal do Panamá, na região central da Republica do Panamá. A informação obtida durante o estudo avaliou fatores de risco da doença de Chagas nesta área. Entre 1999 e 2000, 1110 triatomíneos foram coletados: 1050 triatomíneos (94,6% em palmeiras, 27 (2,4% em habitats periurbanos e 33 (3,0% no interior de casas. Todos os espécimens foram identificados como R. pallescens. Não havia nenhuma evidência de domiciliação do vetor. O exame de glândulas salivares de 380 R. pallescens revelaram taxa de infecção natural por Trypanosoma de 7,6%, mas o conteúdo da ampola rectal de 373 triatomíneos mostrou 45% de positividade. Os perfis de isoenzimas em

  3. Performance of Metarhizium anisopliae-treated foam in combination with Phytoseiulus longipes Evans on Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae).

    Science.gov (United States)

    Azandémè Hounmalon, Ginette Y; Maniania, Nguya K; Niassy, Saliou; Fellous, Simon; Kreiter, Serge; Delétré, Emilie; Fiaboe, Komi K; Martin, Thibaud

    2018-05-13

    Tetranychus evansi (Te) is an exotic pest of solanaceous crops in Africa. The predatory mite Phytoseiulus longipes (Pl) and the fungus Metarhizium anisopliae (Ma), are potential biocontrol agents of Te. The present study investigated efficacy of fungus-treated foam placed above or below the third Te-infested tomato leaf. The persistence of fungus-treated foam and the performance of Pl with or without fungus-treated foam were evaluated. The fungus-treated foam was effective when Te infestation was below the third tomato leaf as no damage was recorded on all upper tomato leaves up to 30 days post-treatment. However, in the control treatments, the infestation increased considerably from 9±0.3% to 100±0% at 15 days post-treatment. The reuse of the fungus-treated foam at 15, 30 and 45 days post-treatment resulted in 19±1.4%, 25±1.2% and 54±2.1% respective infestation by Te. The fungus-treated foam and Pl alone are efficient, but there is no benefit to combinting both against Te. The fungus-treated foam is an effective method to optimize the use of Ma in screenhouse conditions. These two control agents could be integrated in an IPM strategy for crops protection. However, these results need to be confirmed in large field trials. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  4. Trypanosoma cruzi: strain selection by diferent schedules of mouse passage of an initially mixed infection

    Directory of Open Access Journals (Sweden)

    Maria P. Deane

    1984-12-01

    Full Text Available 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.De uma infecção inicialmente dupla em camundongo, estabelecida por inóculo simultaneo e equivalente de formas sanguíneas das cepas Y e F de Trypanosoma cruzi, duas linhagens foram originadas por subinoculações: uma (W passada casa semana, a outra (M cada mês. Por métodos biológicos e bioquímicos apenas a cepa Y foi identificada ao fim a 10a. e 16a. passagens da linhagem W e apenas a cepa F na 2a. e 4a.passagens de linhagem M. Os resultados demonstram a seleção de cepas através de manipulação em laboratorio de populações inicialmente mistas de T. cruzi.

  5. Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis

    Directory of Open Access Journals (Sweden)

    Ludmila R.P. Ferreira

    2008-03-01

    Full Text Available The differentiation of proliferating epimastigote forms of Trypanosoma cruzi , the protozoan parasite that causes Chagas’ disease, into the infective and non-proliferating metacyclic forms can be reproduced in the laboratory by incubating the cells in a chemically-defined medium that mimics the urine of the insect vector. Epimastigotes have a spherical nucleus, a flagellum protruding from the middle of the protozoan cell, and a disk-shaped kinetoplast - an organelle that corresponds to the mitochondrial DNA. Metacyclic trypomastigotes have an elongated shape with the flagellum protruding from the posterior portion of the cell and associated with a spherical kinetoplast. Here we describe the morphological events of this transformation and characterize a novel intermediate stage by three-dimensional reconstruction of electron microscope serial sections. This new intermediate stage is characterized by a kinetoplast compressing an already elongated nucleus, indicating that metacyclogenesis involves active movements of the flagellar structure relative to the cell body. As transcription occurs more intensely in proliferating epimastigotes than in metacyclics, we also examined the presence of RNA polymerase II and measured transcriptional activity during the differentiation process. Both the presence of the enzyme and transcriptional activity remain unchanged during all steps of metacyclogenesis. RNA polymerase II levels and transcriptional activity only decrease after metacyclics are formed. We suggest that transcription is required during the epimastigote-to-metacyclic trypomastigote differentiation process, until the kinetoplast and flagellum reach the posterior position of the parasites in the infective form.A diferenciação de formas epimastigotas (proliferativas do Trypanosoma cruzi, parasita protozoário causador da doença de Chagas, em formas metacíclicas tripomastigotas (infectivas e não proliferativas, pode ser reproduzida em laborat

  6. Production and expression of inflammation and angiogenic parameters triggered by different genetic population of Trypanosoma cruzi.

    OpenAIRE

    Shrestha, Deena

    2014-01-01

    Programa de Pós-Graduação em Ciências Biológicas. Núcleo de Pesquisas em Ciências Biológicas, Pró-Reitoria de Pesquisa e Pós Graduação, Universidade Federal de Ouro Preto. A cardiopatia induzida pela infecção pelo Trypanosoma cruzi aprensenta a inflamação como sua principal característica imunopatológica. Differente células inflamatórias contribuem para a produção de mediatores inflamatorios e regulatórios promotores diretos ou indiretos do processo denominado angiogênese inflamatória. As ...

  7. Iron-associated biology of Trypanosoma brucei.

    Czech Academy of Sciences Publication Activity Database

    Basu, Somsuvro; Horáková, Eva; Lukeš, Julius

    2016-01-01

    Roč. 1860, č. 2 (2016), s. 363-370 ISSN 0304-4165 R&D Projects: GA ČR(CZ) GA14-23986S; GA ČR GAP305/12/2261; GA MŠk(CZ) EE2.3.30.0032 EU Projects: European Commission(XE) COST Action CM1307; European Commission(XE) 316304 - MODBIOLIN Grant - others:AV ČR(CZ) M200961204 Institutional support: RVO:60077344 Keywords : iron * Fe/S cluster * heme * Trypanosoma * TAO Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.702, year: 2016

  8. Species-specific markers for the differential diagnosis of Trypanosoma cruzi and Trypanosoma rangeli and polymorphisms detection in Trypanosoma rangeli.

    Science.gov (United States)

    Ferreira, Keila Adriana Magalhães; Fajardo, Emanuella Francisco; Baptista, Rodrigo P; Macedo, Andrea Mara; Lages-Silva, Eliane; Ramírez, Luis Eduardo; Pedrosa, André Luiz

    2014-06-01

    Trypanosoma cruzi and Trypanosoma rangeli are kinetoplastid parasites which are able to infect humans in Central and South America. Misdiagnosis between these trypanosomes can be avoided by targeting barcoding sequences or genes of each organism. This work aims to analyze the feasibility of using species-specific markers for identification of intraspecific polymorphisms and as target for diagnostic methods by PCR. Accordingly, primers which are able to specifically detect T. cruzi or T. rangeli genomic DNA were characterized. The use of intergenic regions, generally divergent in the trypanosomatids, and the serine carboxypeptidase gene were successful. Using T. rangeli genomic sequences for the identification of group-specific polymorphisms and a polymorphic AT(n) dinucleotide repeat permitted the classification of the strains into two groups, which are entirely coincident with T. rangeli main lineages, KP1 (+) and KP1 (-), previously determined by kinetoplast DNA (kDNA) characterization. The sequences analyzed totalize 622 bp (382 bp represent a hypothetical protein sequence, and 240 bp represent an anonymous sequence), and of these, 581 (93.3%) are conserved sites and 41 bp (6.7%) are polymorphic, with 9 transitions (21.9%), 2 transversions (4.9%), and 30 (73.2%) insertion/deletion events. Taken together, the species-specific markers analyzed may be useful for the development of new strategies for the accurate diagnosis of infections. Furthermore, the identification of T. rangeli polymorphisms has a direct impact in the understanding of the population structure of this parasite.

  9. Characterization of plasma menbrane polypeptides of trypanosoma from bats Caracterização de polipeptídeos de membrana plasmática de tripanosomas de morcegos

    Directory of Open Access Journals (Sweden)

    R. T. Pinho

    1989-03-01

    Full Text Available Cell surface proteins of Trypanosoma dionisii, Trypanosoma vespertilionis and Trypanosoma sp. (M238 were radiodinated and their distribution both in the detergent-poor (DPP and dertergent-enriched phase (DRP was studied using a phase separation technique in Triton X-114 as well as polyacrylamide gel electrophoresis in sodium dodecyl sulphate (SDS-PAGE. Significant differences were observed in the proteins present in the DRP when the three species of trypanosoma were compared. Two major bands with 88 and 70 KDa were observed in T. sp. (M238 but were not detectable in T. dionisii and T. vespertilionis. Three polypeptides whith 96, 77 and 60 KDa were identified in the DRP of T. vespertilionis. Three major bands with 84, 72 and 60 KDa were observed in the DRP of T. dionisii. Two polypeptides with 34-36 KDa present in the DPP, were observed in the three Trypanosome species analyzed. Our observations show that T. sp. (M238 has characteristic surface polypeptides not found in T. vespertilionis.As proteínas de superfície de Trypanosoma dionisii, Trypanosoma vespertilionis e Trypanosoma sp. (M238 foram radiodinados e sua distribuição na fase rica em detergente (DRP e fase pobre em detergente (DPP foram estudadas pela técnica de separação de fases com Triton X-114 e por eletroforese em gel e policrilamida em presença de dodecil sulfato de sódio (SDS-PAGE. Foram observadas diferenças significativas nas prote��nas presentes na DRP quando a três espécies de tripanosomas foram comparadas. Duas bandas com 88 e 70 KDa foram observadas em T. sp. (M238 e não foram detectadas em T. dionisii e t. vespertilionis. Três polípeptídeos com 96, 77 e 60 KDa foram identificados na fase DRP de T. vespertilionis. Três bandas com 84, 72 e 60 KDa foram visualizadas na fase DRP de T. dionisii. Dois polipeptídeos com 34-36 KDA presentes na fase DPP, foram observados nas três espécies de tripanosomas analisadas. Nossas observações mostraram que T. sp. (M

  10. Vaccination with Trypanosoma rangeli induces resistance of guinea pigs to virulent Trypanosoma cruzi.

    Science.gov (United States)

    Basso, B; Moretti, E; Fretes, R

    2014-01-15

    Chagas' disease, endemic in Latin America, is spread in natural environments through animal reservoirs, including marsupials, mice and guinea pigs. Farms breeding guinea pigs for food are located in some Latin-American countries with consequent risk of digestive infection. The aim of this work was to study the effect of vaccination with Trypanosoma rangeli in guinea pigs challenged with Trypanosoma cruzi. Animals were vaccinated with fixated epimastigotes of T. rangeli, emulsified with saponin. Controls received only PBS. Before being challenged with T. cruzi, parasitemia, survival rates and histological studies were performed. The vaccinated guinea pigs revealed significantly lower parasitemia than controls (pguinea pigs and dogs. The development of vaccines for use in animals, like domestic dogs and guinea pigs in captivity, opens up new opportunities for preventive tools, and could reduce the risk of infection with T. cruzi in the community. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Classical clinical signs in rats experimemtally infected with Trypanosoma brucei

    Directory of Open Access Journals (Sweden)

    Nwoha Rosemary Ijeoma Ogechi

    2015-02-01

    Full Text Available Objective: To investigate clinical signs in Trypanosoma brucei infection in albino rats. Methods: Fourteen rats grouped into 2 with 7 rats in each group were used to determine classical clinical manifestation of Trypanosoma brucei infection in rats. Group A rats were uninfected control and Group B rats were infected with Trypanosoma brucei. Results: Parasitaemia was recorded in Group B by (3.86±0.34 d and the peak of parasitaemia was observed at Day 5 post infection. Classical signs observed included squint eyes, raised whiskers, lethargy, no weight loss, pyrexia, isolation from the other rats, and starry hair coat. Conclusions: These signs could be diagnostic or aid in diagnosis of Trypanosoma brucei infection in rats.

  12. Role of cytokines in Trypanosoma brucei-induced anaemia: A ...

    African Journals Online (AJOL)

    species Trypanosoma brucei that are transmitted by a tsetse fly (Glossina spp.) ... of autologous immunoglobulin antibodies on the red cell surfaces and also to ... development for the detection and management of anaemia in trypanosomiasis.

  13. Quantitative Proteomic and Phosphoproteomic Analysis of Trypanosoma cruzi Amastigogenesis

    DEFF Research Database (Denmark)

    Queiroz, Rayner M L; Charneau, Sebastien; Mandacaru, Samuel C

    2014-01-01

    Chagas disease is a tropical neglected disease endemic in Latin America and it is caused by the protozoan Trypanosoma cruzi. The parasite has four major life stages: epimastigote, metacyclic trypomastigote, bloodstream trypomastigote and amastigote. The differentiation from infective trypomastigo......Chagas disease is a tropical neglected disease endemic in Latin America and it is caused by the protozoan Trypanosoma cruzi. The parasite has four major life stages: epimastigote, metacyclic trypomastigote, bloodstream trypomastigote and amastigote. The differentiation from infective...

  14. Molecular basis of mammalian cell invasion by Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Nobuko Yoshida

    2006-03-01

    Full Text Available Establishment of infection by Trypanosoma cruzi, the agent of Chagas' disease, depends on a series of events involving interactions of diverse parasite molecules with host components. Here we focus on the mechanisms of target cell invasion by metacyclic trypomastigotes (MT and mammalian tissue culture trypomastigotes (TCT. During MT or TCT internalization, signal transduction pathways are activated both in the parasite and the target cell, leading to Ca2+ mobilization. For cell adhesion, MT engage surface glycoproteins, such as gp82 and gp35/50, which are Ca2+ signal-inducing molecules. In T. cruzi isolates that enter host cells in gp82-mediated manner, parasite protein tyrosine kinase as well as phospholipase C are activated, and Ca2+ is released from I P3-sensitive stores, whereas in T. cruzi isolates that attach to target cells mainly through gp35/50, the signaling pathway involving adenylate cyclase appears to be stimulated, with Ca2+ release from acidocalciosomes. In addition, T. cruzi isolate-dependent inhibitory signals, mediated by MT-specific gp90, may be triggered both in the host cell and the parasite. The repertoire of TCT molecules implicated in cell invasion includes surface glycoproteins of gp85 family, with members containing binding sites for laminin and cytokeratin 18, enzymes such as cruzipain, trans-sialidase, and an oligopeptidase B that generates a Ca2+-agonist from a precursor molecule.O estabelecimento da infecção por Trypanosoma cruzi, o agente da doença de Chagas, depende de uma série de eventos envolvendo interações de diversas moléculas do parasita com componentes do hospedeiro. Focalizamos aqui os mecanismos de invasão celular por tripomastigotas metacíclicos (TM e por tripomastigotas de cultura de tecido (TCT. Durante a internalização de TM ou TCT, vias de transdução de sinal são ativadas tanto no parasita como na célula alvo, acarretando a mobilização de Ca2+. Para adesão, TM utiliza as glicoprote

  15. The haemoculture of Trypanosoma minasense chagas, 1908

    Directory of Open Access Journals (Sweden)

    Mariangela Ziccardi

    1996-08-01

    Full Text Available Trypanosoma minasense was isolated for the first time in blood axenic culture from a naturally infected marmoset, Callithrix penicillata, from Brazil. The parasite grew profusely in an overlay of Roswell Park Memorial Institute medium plus 20% foetal bovine serum, on Novy, McNeal and Nicolle medium (NNN , at 27°C, with a peak around 168 hr. The morphometry of cultural forms of T. minasense, estimates of cell population size and comparative growth in four different media overlays always with NNN, were studied. The infectivity of cultural forms to marmosets (C. penicillata and C. jacchus and transformation of epimastigotes into metacyclic-like forms in axenic culture in the presence of chitin derivates (chitosan were evaluated.

  16. Effects of betamethasone on the course of experimentai. Infection with Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Frederico G.C. Abath

    1986-09-01

    Full Text Available In this experiment, the effect of betamethasone administered in the early post- acute infection of mice by Trypanosoma cruzi was studied. This drug was administered during 30 days after the 42nd day of infection in a dose of 0.15 mg/day. The betamethasone treatment did not cause fresh outbreaks of parasitemia and the histopathological findings in the chronic phase were not different from those in the control group. The higher cumulative mortality after treatment in the experimental group was due to superimposed bacterial infections. Outbred albino mice infected with low numbers ofY strain Trypanosoma cruzi trypomastigotes were not suitable models for Chagas' disease, since after 7 months of observation only mild histological lesions developed in all the animais. Prolonged betamethasone treatment of mice infected with low numbers o/Trypanosoma cruzi of the Y strain, during the post-acute phase did not aggravate the course of infection.Foram estudados os efeitos da betametasona administrada na fase pós-aguda imediata de uma infecção pelo T. cruzi em camundongos. O tratamento consistiu de 30 doses diárias de 0,15 mg de betametasona, a partir de 42° dia de infecção, não havendo aparecimento de novos surtos de parasitemia. No tempo de duração do experimento (7 meses não houve diferença entre as lesões histopatológicas dos animais tratados e dos não tratados. O grupo experimental apresentou uma maior mortalidade acumulada no 75º dia de infecção, o que pode ser atribuído a infecções bacterianas associadas. Por outro lado, camundongos albinos "outbred", infectados com baixo inóculo, não se apresentaram como bom modelo de doença de Chagas, já que não desenvolveram lesões importantes nem na fase aguda nem após 7 meses de infecção. Em conclusão, o tratamento imunosupressivo prolongado, após a fase aguda de uma infecção mínima com a cepa Ydo T. cruzi não tem influência sobre o curso da infecção, pelo menos no que tange

  17. Novo processo para triagem de medicamentos na infecção experimental pelo Trypanosoma cruzi Proposal of a new process for screening of drugs in experimental infection with Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Rubens Campos

    1991-08-01

    Full Text Available É proposto processo para a triagem da capacidade terapêutica de medicamentos na infecção experimental pelo Trypanosoma cruzi. O método tem base no emprego de triatomíneos parasitados que se alimentam, decorridos períodos diferentes para haver compatibilização com níveis sangüíneos, em camundongos aos quais foi administrado o fármaco sob apreciação; assim, o tubo digestivo do hemíptero participará como estrutura propícia à avaliação. Em observação inicial, ocorreu utilização do benzonidazol, que se mostrou apenas parcialmente ativo, pelo menos de acordo com a maneira de execução do novo procedimento.We propose a screening process for detection of therapeutic activity of drugs against experimental infection with Trypanosoma cruzi. It is based on the use of infected tryatominae that are fed on mice which have received the study drug. Blood meals are made at different time schedule in order to adapt with serum drug levels. The digestive tube of the hemyptera will, thus, work as a suitable structure for examination. In a initial observation, benzonidazole was used, and was shown to be only partially active at least in the conditions of this new procedure.

  18. Cell signaling during Trypanosoma cruzi invasion

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    Fernando Yukio Maeda

    2012-11-01

    Full Text Available Cell signaling is an essential requirement for mammalian cell invasion by Trypanosoma cruzi. Depending on the parasite strain and the parasite developmental form, distinct signaling pathways may be induced. In this short review, we focus on the data coming from studies with metacyclic trypomastigotes (MT generated in vitro and tissue culture-derived trypomastigotes (TCT, used as counterparts of insect-borne and bloodstream parasites respectively. During invasion of host cells by MT or TCT, intracellular Ca2+ mobilization and host cell lysosomal exocytosis are triggered. Invasion mediated by MT surface molecule gp82 requires the activation of mammalian target of rapamycin (mTOR, phosphatidylinositol 3-kinase (PI3K and protein kinase C (PKC in the host cell, associated with Ca2+-dependent disruption of the actin cytoskeleton. In MT, protein tyrosine kinase (PTK, PI3K, phospholipase C (PLC and PKC appear to be activated. TCT invasion, on the other hand, does not rely on mTOR activation, rather on target cell PI3K, and may involve the host cell autophagy for parasite internalization. Enzymes, such oligopeptidase B and the major T. cruzi cysteine proteinase cruzipain, have been shown to generate molecules that induce target cell Ca2+ signal. In addition, TCT may trigger host cell responses mediated by TGF-β receptor or integrin family member. Further investigations are needed for a more complete and detailed picture of T. cruzi invasion.

  19. Flagellar Motility of Trypanosoma cruzi Epimastigotes

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    G. Ballesteros-Rodea

    2012-01-01

    Full Text Available The hemoflagellate Trypanosoma cruzi is the causative agent of American trypanosomiasis. Despite the importance of motility in the parasite life cycle, little is known about T. cruzi motility, and there is no quantitative description of its flagellar beating. Using video microscopy and quantitative vectorial analysis of epimastigote trajectories, we find a forward parasite motility defined by tip-to-base symmetrical flagellar beats. This motion is occasionally interrupted by base-to-tip highly asymmetric beats, which represent the ciliary beat of trypanosomatid flagella. The switch between flagellar and ciliary beating facilitates the parasite's reorientation, which produces a large variability of movement and trajectories that results in different distance ranges traveled by the cells. An analysis of the distance, speed, and rotational angle indicates that epimastigote movement is not completely random, and the phenomenon is highly dependent on the parasite behavior and is characterized by directed and tumbling parasite motion as well as their combination, resulting in the alternation of rectilinear and intricate motility paths.

  20. Differential gene expression during Trypanosoma cruzi metacyclogenesis

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    Marco Aurelio Krieger

    1999-09-01

    Full Text Available The transformation of epimastigotes into metacyclic trypomastigotes involves changes in the pattern of expressed genes, resulting in important morphological and functional differences between these developmental forms of Trypanosoma cruzi. In order to identify and characterize genes involved in triggering the metacyclogenesis process and in conferring to metacyclic trypomastigotes their stage specific biological properties, we have developed a method allowing the isolation of genes specifically expressed when comparing two close related cell populations (representation of differential expression or RDE. The method is based on the PCR amplification of gene sequences selected by hybridizing and subtracting the populations in such a way that after some cycles of hybridization-amplification genes specific to a given population are highly enriched. The use of this method in the analysis of differential gene expression during T. cruzi metacyclogenesis (6 hr and 24 hr of differentiation and metacyclic trypomastigotes resulted in the isolation of several clones from each time point. Northern blot analysis showed that some genes are transiently expressed (6 hr and 24 hr differentiating cells, while others are present in differentiating cells and in metacyclic trypomastigotes. Nucleotide sequencing of six clones characterized so far showed that they do not display any homology to gene sequences available in the GeneBank.

  1. Studies on the glycosome of Trypanosoma brucei

    International Nuclear Information System (INIS)

    Aman, R.A.

    1985-01-01

    Glycosomes (microbodies) have been purified from bloodstream form Trypanosoma brucei by an improved procedure involving freezing and thawing live organisms in 15% glycerol prior to cell disruption. Highly purified organelles of bloodstream form T. brucei contain 11 major proteins of which 8 tentatively identified glycolytic enzymes make up about 90% of the total glycosomal protein. Treatment of these intact isolated organelles with the bisimidoester dimethylsuberimidate (DMSI) resulted in crosslinking of all glycosomal proteins into a large complex suggestive of juxtapositioning of the glycosomal proteins. The crosslinked complex was capable of catalyzing the multienzyme conversion of glucose to glycerol-3-phosphate but did not possess any special kinetic features different from those of the unaggregated enzymes represented by solubilized glycosomes. The multienzyme reaction had a lab phase associated with it and [ 14 C]-glucose label incorporation into sugar phosphate intermediates was effectively competed by unlabeled intermediates. Glycosomes were also purified from culture form T. brucei by several different procedures. Comparison of highly purified organelles from the two different life stages of the organism showed reduced specific activities and contents of the early glycolytic enzymes in organelles from the culture form with a decrease from 87% to 35% of the contribution of glycolytic enzymes to the total glycosomal protein

  2. First record of Trypanosoma chattoni in Brazil and occurrence of other Trypanosoma species in Brazilian frogs (Anura, Leptodactylidae).

    Science.gov (United States)

    Lemos, M; Morais, D H; Carvalho, V T; D'Agosto, M

    2008-02-01

    The present study provides the first record of Trypanosoma chattoni Mathis and Leger, 1911, in a new host, Leptodactylus fuscus Schneider, 1799 (Anura, Leptodactylidae), and the occurrence of Trypanosoma rotatorium-like species in Leptodactylus chaquensis Cei, 1950. The anurans were captured in the State of Mato Grosso, Brazil. Blood samples were obtained by cardiac puncture, and blood smears were examined for the presence of hemoparasites. The Trypanosoma rotatorium-like species in this study refers to a short-bodied trypomastigote that has a conspicuous undulating membrane but lacks a free flagellum; T. chattoni refers to a monomorphic parasite that has a rounded body, a kinetoplast adjacent to the nucleus, and a short flagellum.

  3. EPIDEMIOLOGÍA MOLECULAR DE TRYPANOSOMA CRUZI

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    Felipe Guhl

    2013-01-01

    Full Text Available La enfermedad de Chagas causada por el parásito Trypanosoma cruzi es una zoonosis compleja, ampliamente distribuida en el continente americano. La infección puede ser adquirida a través de las heces de insectos triatominos, transfusión de sangre, trasplante de órganos, vía oral, por transmisión congénita y por accidentes de laboratorio. El completo entendimiento de la etiología y epidemiología de la enfermedad de Chagas a través de su distribución geográfica es complejo y permanece bajo intensa investigación hasta la actualidad. Los recientes estudios sobre la variabilidad genética del parásito han dado nuevas luces de los diferentes escenarios de los ciclos de transmisión de la enfermedad y su patogénesis en humanos. El propósito principal para la caracterización molecular de T.cruzi y sus múltiples genotipos está dirigido hacia su asociación con la clínica y la patogenesis de la enfermedad, así como al esclarecimiento de los diferentes escenarios de transmisión y los aspectos coevolutivos relacionados con reservorios e insectos vectores. La caracterización molecular de los diferentes aislamientos a partir de humanos, insectos y reservorios, ha permitido identificar la amplia variabilidad genética del parásito, abriendo nuevos caminos hacia la búsqueda de nuevos blancos terapéuticos y pruebas diagnósticas más específicas que contribuyan a mitigar la enfermedad de Chagas.

  4. Trypanosoma brucei mitochondrial respiratome: Composition and organization in procyclic form

    KAUST Repository

    Acestor, Nathalie

    2011-05-24

    The mitochondrial respiratory chain is comprised of four different protein complexes (I-IV), which are responsible for electron transport and generation of proton gradient in the mitochondrial intermembrane space. This proton gradient is then used by F oF 1-ATP synthase (complex V) to produce ATP by oxidative phosphorylation. In this study, the respiratory complexes I, II, and III were affinity purified from Trypanosoma brucei procyclic form cells and their composition was determined by mass spectrometry. The results along with those that we previously reported for complexes IV and V showed that the respiratome of Trypanosoma is divergent because many of its proteins are unique to this group of organisms. The studies also identified two mitochondrial subunit proteins of respiratory complex IV that are encoded by edited RNAs. Proteomics data from analyses of complexes purified using numerous tagged component proteins in each of the five complexes were used to generate the first predicted protein-protein interaction network of the Trypanosoma brucei respiratory chain. These results provide the first comprehensive insight into the unique composition of the respiratory complexes in Trypanosoma brucei, an early diverged eukaryotic pathogen. © 2011 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. A tropical tale: how Naja nigricollis venom beats Trypanosoma brucei

    DEFF Research Database (Denmark)

    Martos Esteban, Andrea; Laustsen, Andreas Hougaard; Carrington, Mark

    Trypanosoma brucei is a parasitic protozoan species capable to infecting insect vectors whose bite further produces African sleeping sickness inhuman beings [1]. During the parasite’s extracellular life in the mammalian host,its outer coat, mainly composed of Variable Surface Glycoproteins (VSGs)...

  6. What controls glycolysis in bloodstream form Trypanosoma brucei?

    NARCIS (Netherlands)

    Bakker, B.M.; Michels, P.A.M.; Opperdoes, F.R.; Westerhoff, H.V.

    1999-01-01

    On the basis of the experimentally determined kinetic properties of the trypanosomal enzymes, the question is addressed of which step limits the glycolytic flux in bloodstream form Trypanosoma brucei. There appeared to be no single answer; in the physiological range, control shifted between the

  7. Trypanosoma cruzi: avirulence of the PF strain to Callithrix marmosets

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    Humberto Menezes

    1981-06-01

    Full Text Available Callithrix jacchus geoffroy marmosets (HumBol. 1812 were injected once subcutaneously with 10.000 parasites/g body weight and followed for a period of six months. The PF strain of Trypanosoma cruzi was used. Follow-up was done through blood cultures, xenodiagnosis, serological tests, and ECG. A small number of normaI animais served as control.

  8. Role of sialic acids in the midguts of Trypanosoma congolense ...

    African Journals Online (AJOL)

    Administrator

    total sialic acid concentration. The relevance of these findings to the role of sialic acids in the midgut of. T. congolense infected C.p. pipiense mosquitoes is discussed in this paper. Key words: Trypanosoma congolense, Culex pipiense pipiense, sialic acid, midgut. INTRODUCTION. The Culex pipiense pipiense mosquito is ...

  9. Serum total protein, albumin and globulin levels in Trypanosoma ...

    African Journals Online (AJOL)

    The effect of orally administered Scoparia dulcis on Trypanosoma brucei-induced changes in serum total protein, albumin and globulin were investigated in rabbits over a period of twenty eight days. Results obtained show that infection resulted in hyperproteinaemia, hyperglobulinaemia and hypoalbuminaemia. However ...

  10. DNA content analysis allows discrimination between Trypanosoma cruzi and Trypanosoma rangeli.

    Science.gov (United States)

    Naves, Lucila Langoni; da Silva, Marcos Vinícius; Fajardo, Emanuella Francisco; da Silva, Raíssa Bernardes; De Vito, Fernanda Bernadelli; Rodrigues, Virmondes; Lages-Silva, Eliane; Ramírez, Luis Eduardo; Pedrosa, André Luiz

    2017-01-01

    Trypanosoma cruzi, a human protozoan parasite, is the causative agent of Chagas disease. Currently the species is divided into six taxonomic groups. The genome of the CL Brener clone has been estimated to be 106.4-110.7 Mb, and DNA content analyses revealed that it is a diploid hybrid clone. Trypanosoma rangeli is a hemoflagellate that has the same reservoirs and vectors as T. cruzi; however, it is non-pathogenic to vertebrate hosts. The haploid genome of T. rangeli was previously estimated to be 24 Mb. The parasitic strains of T. rangeli are divided into KP1(+) and KP1(-). Thus, the objective of this study was to investigate the DNA content in different strains of T. cruzi and T. rangeli by flow cytometry. All T. cruzi and T. rangeli strains yielded cell cycle profiles with clearly identifiable G1-0 (2n) and G2-M (4n) peaks. T. cruzi and T. rangeli genome sizes were estimated using the clone CL Brener and the Leishmania major CC1 as reference cell lines because their genome sequences have been previously determined. The DNA content of T. cruzi strains ranged from 87,41 to 108,16 Mb, and the DNA content of T. rangeli strains ranged from 63,25 Mb to 68,66 Mb. No differences in DNA content were observed between KP1(+) and KP1(-) T. rangeli strains. Cultures containing mixtures of the epimastigote forms of T. cruzi and T. rangeli strains resulted in cell cycle profiles with distinct G1 peaks for strains of each species. These results demonstrate that DNA content analysis by flow cytometry is a reliable technique for discrimination between T. cruzi and T. rangeli isolated from different hosts.

  11. Biochemical behavior of Trypanosoma cruzi strains isolated from mice submitted to specific chemotherapy

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    Jesila Pinto M. Marretto

    1994-12-01

    Full Text Available To investigate the influence of chemotherapy on the biochemical beha vior of Trypanosoma cruzi strains, three groups of mice were infected with one of three strains of T. cruzi of different biological and isoenzymic patterns (Peruvian, 21 SF and Colombian strains. Each group was subdivided into subgroups: 1 - treated with nifurtimox; 2 - treated with benznidazole and 3 - untreated infected controls. At the end of treatment, that lasted for 90 days, xenodiagnosis, sub inoculation of blood into new born mice and haemoculture were performed as tests of cure. From the positive tests, 22 samples of T. cruzi were isolated from all subgroups. Electrophoretic analysis of the isoenzymes PGM, GP1, ALAT and AS AT failed to show any difference between parasite strains isolated from treated and untreated mice, which indicates that no detectable clonal selection or parasite genetic markers alterations concerning the isoenzymes analysed have been determined by treatment with drugs of recognized antiparasitic effect, suggesting stability of the phenotypic characteristics of the three biological types of T. cruzi strains.Com o objetivo de investigar a influência da quimioterapia no padrão bioquímico de diferentes cepas do Trypanosoma cruzi, três grupos de camundongos foram infectados respectivamente com as cepas Peruana, 21 SF e Colombiana, que correspondem a diferentes padrões biológicos e isoenzimáticos. Cada grupo foi subdividido em subgrupos: 1 - tratados com nifurtimox; 2 - tratados com benzonidazol; 3- controles infectados não tratados. Ao final do tratamento que durou 90 dias, os animais foram submetidos a testes parasitológicos de cura: xenodiagnóstico, subinoculação do sangue em camundongos recém-nascidos e hemocultura em meio Warren. A partir da positivação destes testes, foram isoladas 22 amostras do T. cruzi dos três subgrupos. A análise eletroforética dos extratos enzimáticos obtidos após cultura para as enzimas PGM, GPI, ALAT e

  12. Characterization and immobilization of engineered sialidases from <em>Trypanosoma rangeliem> for transsialylation

    DEFF Research Database (Denmark)

    Zeuner, Birgitte; González-Delgado, Isabel; Holck, Jesper

    2017-01-01

    transsialylation activity: both had a 14 times higher ratio between transsialylation and hydrolysis products compared to the first reported mutant TrSA5mut. In the current work, these two variants, Tr15 and Tr16, were characterized in terms of pH optimum, thermal stability, effect of acceptor-to-donor ratio......, and acceptor specificity for transsialylation using casein glycomacropeptide (CGMP) as sialyl donor and lactose or other human milk oligosaccharide core structures as acceptors. Both sialidase variants exhibited pH optima around pH 4.8. Thermal stability of each enzyme was comparable to that of previously...... developed T. rangeli sialidase variants and higher than that of the native transsialidase from T. cruzi (TcTS). As for other engineered T. rangeli sialidase variants and TcTS, the acceptor specificity was broad: lactose, galactooligosaccharides (GOS), xylooligosaccharides (XOS), and human milk...

  13. Dogs infection by Trypanosoma cruzi in São Domingos do Capim, State of Pará, Brazil

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    Vívian Tavares Almeida

    2015-12-01

    Full Text Available ABSTRACT. Almeida V.T., Kobayashi Y.T. da S., Roque A.L.R., Barros J.H.S., de Castro L.R.S., Madeira E.A.O., Uzcategui R.A.R. & Fernandes J.I. Dogs infection by Trypanosoma cruzi in São Domingos do Capim, State of Pará, Brazil. [Infecção por Trypanosoma cruzi em cães em São Domingos do Capim, Estado do Pará, Brasil.] Revista Brasileira de Medicina Veterinária, 37(supl. 1:106- 112, 2015. Programa de Pós-Graduação em Saúde Animal na Amazônia, Universidade Federal do Pará, Campus II, BR 316 Km 62, Castanhal, PA 68743-970, Brasil. E-mail: vitalmeida21@hotmail.com The objective of this study was to determine the presence of Trypanosoma cruzi among dogs naturally infected by it inside four rural communities at the Municipality of São Domingos do Capim located in the Northeastern Pará, Brazil. Blood samples were collected from 113 dogs and 85.7% (30/35 of the serologically positive dogs had their blood re-collected after three months. The diagnosis of T. cruzi infection was performed by: fresh blood examination, hemoconcentration, hemoculture, as well as the serological assays Indirect Immunofluorescence Essay (IFAT and Imunoenzimatic essay (ELISA. The presence of positive dogs in both serologic tests (IFAT + ELISA was 31% (35/113, distributed among the four communities as follows: (12/44 Uricuriteua, (19/40 Cezaréia, (1/16 Aliança and (3/13 Catita. None of the samples was positive in the fresh blood examination or hemoconcentration, although it was possible to isolate T. cruzi, DTU TcI in one dog sample during its blood re-collection. These results show how dogs are exposed to the T. cruzi transmission cycle, revealing their importance as sentinels for the presence of this parasite in the studied area.

  14. Estudo do comportamento biológico de três amostras de trypanosoma cruzi isoladas de pacientes do instituto "dante pazzanese" de cardiologia

    OpenAIRE

    Pereira,Vera Lúcia; Zamorano,Mabel M. B.; Boainain,Elias

    1987-01-01

    Foram estudadas três amostras de Trypanosoma cruzi isoladas de pacientes. As amostras foram observadas sob os seguintes parâmetros: níveis parasitêmicos, morfologia das formas sanguíneas, alterações histopatológicas, virulência e mortalidade em camundongos. A amostra IDPC-1 foi isolada de um paciente naturalmente infectado e tratado com benzonidazol. Provocou baixos índices parasitêmicos e mostrou baixa virulência, sendo que 83,4% dos animais evoluiram para a fase crônica. Os tripomastigotas ...

  15. Unusual way of feeding by the deutonymph of Neottialges evansi (Actinotrichida, Astigmata, Hypoderatidae), a subcutaneous parasite of cormorants, revealed by fine structural analyses.

    Science.gov (United States)

    Alberti, Gerd; Kanarek, Gerard; Dabert, Jacek

    2016-10-01

    The parasitic deutonymphs of hypoderatid mites live within the subcutaneous layer of their avian hosts, where they become greatly engorged despite not having functional mouthparts. The method by which they take up nutrients has been mysterious up to now. Here, we report on the morphology of hypoderatid deutonymphs using scanning and transmission electron microscopy and describe structures that may resolve the mystery. The deutonymph of Neottialges evansi (Hypoderatidae) from the cormorant Phalacrocorax carbo is a simply organized stage lacking both mouthparts and a functional foregut. The structure of midgut and hindgut indicate that they are not capable of processing food. The midgut consists of highly branching flat cells and rarely shows a lumen. Almost the entire space between integument, gut remnants and other organs (synganglion, developing gonads) is filled by huge cells containing protein and glycogen granules and numerous lipid inclusions. The anal opening is minute. The structure of the cuticle and epidermis suggests that nutrients are not absorbed through the general integument. Thus the two main existing hypotheses about feeding modes in hypoderatid deutonymphs, anal vs. integumentary food absorbtion, are not supported. We suggest instead that two pairs of genital papillae showing peculiar microanatomical features are actively involved in movement of liquid materials between host and mite and most probably are the nutrient-intake organs. J. Morphol. 277:1368-1389, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  16. Feeding success of Lutzomyia evansi (Diptera: Psychodidae) experimentally exposed to small mammal hosts in an endemic focus of Leishmania chagasi in northern Colombia.

    Science.gov (United States)

    Adler, Gregory H; Becerra, María Teresa; Travi, Bruno L

    2003-12-01

    Lutzomyia evansi is the vector of Leishmania chagasi in northern Colombia. Differences in feeding success were revealed, when this phlebotomine sand fly was fed on five species of small mammal hosts from an endemic focus of visceral leishmaniasis. In each trial, 50 female sand flies were provided access to similar-sized depilated areas of the hind foot of each of 44 individual mammals and allowed to feed for 30 minutes. The number of engorged sand flies was counted at the end of each trial and compared among host species by analysis of variance and Tukey's multiple comparisons test. Sand flies fed least successfully on Sciurus granatensis, a common squirrel in the endemic area. It has not been found infected with L. chagasi. Intermediate numbers of sand flies engorged on Heteromys anomalus and Zygodontomys brevicauda, but these two mammals have not been found infected with L. chagasi and are not expected to be important in transmission. Sand flies fed most successfully on Didelphis marsupialis and Proechimys canicollis. These are the two most abundant mammals in the endemic area and frequently are infected. Results provided further evidence that these two species are the wild mammals with the greatest impact on transmission of L. chagasi in northern Colombia.

  17. Comparative analysis of the kinomes of three pathogenic trypanosomatids: Leishmania major, Trypanosoma brucei and Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Ward Pauline N

    2005-09-01

    Full Text Available Abstract Background The trypanosomatids Leishmania major, Trypanosoma brucei and Trypanosoma cruzi cause some of the most debilitating diseases of humankind: cutaneous leishmaniasis, African sleeping sickness, and Chagas disease. These protozoa possess complex life cycles that involve development in mammalian and insect hosts, and a tightly coordinated cell cycle ensures propagation of the highly polarized cells. However, the ways in which the parasites respond to their environment and coordinate intracellular processes are poorly understood. As a part of an effort to understand parasite signaling functions, we report the results of a genome-wide analysis of protein kinases (PKs of these three trypanosomatids. Results Bioinformatic searches of the trypanosomatid genomes for eukaryotic PKs (ePKs and atypical PKs (aPKs revealed a total of 176 PKs in T. brucei, 190 in T. cruzi and 199 in L. major, most of which are orthologous across the three species. This is approximately 30% of the number in the human host and double that of the malaria parasite, Plasmodium falciparum. The representation of various groups of ePKs differs significantly as compared to humans: trypanosomatids lack receptor-linked tyrosine and tyrosine kinase-like kinases, although they do possess dual-specificity kinases. A relative expansion of the CMGC, STE and NEK groups has occurred. A large number of unique ePKs show no strong affinity to any known group. The trypanosomatids possess few ePKs with predicted transmembrane domains, suggesting that receptor ePKs are rare. Accessory Pfam domains, which are frequently present in human ePKs, are uncommon in trypanosomatid ePKs. Conclusion Trypanosomatids possess a large set of PKs, comprising approximately 2% of each genome, suggesting a key role for phosphorylation in parasite biology. Whilst it was possible to place most of the trypanosomatid ePKs into the seven established groups using bioinformatic analyses, it has not been

  18. The pentose phosphate pathway in Trypanosoma cruzi: a potential target for the chemotherapy of Chagas disease

    Directory of Open Access Journals (Sweden)

    Mariana Igoillo-Esteve

    2007-12-01

    Full Text Available Trypanosoma cruzi is highly sensitive to oxidative stress caused by reactive oxygen species. Trypanothione, the parasite's major protection against oxidative stress, is kept reduced by trypanothione reductase, using NADPH; the major source of the reduced coenzyme seems to be the pentose phosphate pathway. Its seven enzymes are present in the four major stages in the parasite's biological cycle; we have cloned and expressed them in Escherichia coli as active proteins. Glucose 6-phosphate dehydrogenase, which controls glucose flux through the pathway by its response to the NADP/NADPH ratio, is encoded by a number of genes per haploid genome, and is induced up to 46-fold by hydrogen peroxide in metacyclic trypomastigotes. The genes encoding 6-phosphogluconolactonase, 6-phosphogluconate dehydrogenase, transaldolase and transketolase are present in the CL Brener clone as a single copy per haploid genome. 6-phosphogluconate dehydrogenase is very unstable, but was stabilized introducing two salt bridges by site-directed mutagenesis. Ribose-5-phosphate isomerase belongs to Type B; genes encoding Type A enzymes, present in mammals, are absent. Ribulose-5-phosphate epimerase is encoded by two genes. The enzymes of the pathway have a major cytosolic component, although several of them have a secondary glycosomal localization, and also minor localizations in other organelles.Trypanosoma cruzi é altamente sensível ao estresse oxidativo causado por espécies reativas do oxigênio. Tripanotiona, o principal protetor do parasita contra o estresse oxidativo, é mantido reduzido pela tripanotiona redutase, pela presença deNADPH; a principal fonte da coenzima reduzida parece ser a via da pentose fosfato. As sete enzimas dessa via estão presentes nos quatro principais estágios do ciclo biológico do parasita; nós clonamos e expressamos as enzimas em Escherichia coli como proteínas ativas. Glucose 6-fosfato desidrogenase, que controla o fluxo da glucose da

  19. Biodemes and zymodemes of Trypanosoma cruzi strains: correlations with clinical data and experimental pathology

    Directory of Open Access Journals (Sweden)

    Sonia G. Andrade

    1997-02-01

    Full Text Available With the objective of establishing biological and biochemical characteristics of a significant number of Trypanosoma cruzi strains from different geographical areas, 138 strains isolated from naturally infected humans, triatomine or vertebrate hosts were studied; 120 were isolated from different areas of Brazil and 18 from other South and Central American countries. Inocula from triatomine or culture forms were injected into suckling Swiss mice, followed by passages into mice 10 to 12 g. Biological characters and histopathological study permitted the inclusion of the strains into three Types or biodemes: I, II, III. Isoenzymic analysis confirmed a correspondence between the biodemes and zymodemes : Type I and Z2b, Type II and Z2, Type III and Z1. Results showed the ubiquitary distribution of the several types of strains. The predominance of the same Type and zymodeme in one geographical area was confirmed : Type II strains among the human cases from eastern Bahia and east of Goiás; Type III strains from humans of north Brazil and Central America and from silvatic vectors or vertebrates from other geographical areas. The biological types of strains correlate with different histopathological lesions considering cardiac involvement and neuronal lesions. These findings suggest that the biological behavior together with isoenzymes patterns and pathological pictures in the vertebrate host can be an important tool for establishing correlations between strains behavior and clinico-pathological manifestations of Chagas' disease in different geographical areas.Foram estudados os caracteres biológicos e isoenzimáticos de 138 cepas do Trypanosoma cruzi de diferentes áreas geográficas, sendo 120 do Brasil e 18 de outros paises da América do Sul e Central. Camundongos recém-nascidos foram inoculados com formas metacíclicas de triatomineos ou de culturas axenicas, seguindo-se passagem em camundongo de 10 a 12g. Os caracteres biológicos e o estudo

  20. Meiosis and Haploid Gametes in the Pathogen Trypanosoma brucei

    OpenAIRE

    Peacock, Lori; Bailey, Mick; Carrington, Mark; Gibson, Wendy

    2014-01-01

    Summary In eukaryote pathogens, sex is an important driving force in spreading genes for drug resistance, pathogenicity, and virulence [1]. For the parasitic trypanosomes that cause African sleeping sickness, mating occurs during transmission by the tsetse vector [2, 3] and involves meiosis [4], but haploid gametes have not yet been identified. Here, we show that meiosis is a normal part of development in the insect salivary glands for all subspecies of Trypanosoma brucei, including the human...

  1. Trypanosoma brucei Mitochondrial Respiratome: Composition and Organization in Procyclic Form

    Czech Academy of Sciences Publication Activity Database

    Acestor, N.; Zíková, Alena; Dalley, R. A.; Anupama, A.; Panigrahi, A. K.; Stuart, K. D.

    2011-01-01

    Roč. 10, č. 9 (2011), s. 1-14 ISSN 1535-9476 R&D Projects: GA ČR GP204/09/P563 Institutional research plan: CEZ:AV0Z60220518 Keywords : SUCCINATE DEHYDROGENASE * EDITED MESSENGER-RNA * COMPLEX-I * TRYPANOSOMA-BRUCEI * UBIQUINONE OXIDOREDUCTASE * TAP-TAG * PROTEIN INTERACTION * ALTERNATIVE OXIDASE * STATISTICAL-MODEL * MASS-SPECTROMETRY Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.398, year: 2011

  2. Trypanosoma brucei solanesyl-diphosphate synthase localizes to the mitochondrion

    Czech Academy of Sciences Publication Activity Database

    Lai, D.-H.; Bontempi, E. J.; Lukeš, Julius

    2012-01-01

    Roč. 183, č. 2 (2012), s. 189-192 ISSN 0166-6851 R&D Projects: GA ČR(CZ) GAP305/11/2179 Institutional support: RVO:60077344 Keywords : Trypanosoma brucei * Sleeping sickness * Ubiquinone * Solanesyl-diphosphate synthase * Digitonin permeabilization * In situ tagging Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.734, year: 2012 http://www.sciencedirect.com/science/article/pii/S0166685112000539

  3. Regulation and spatial organization of PCNA in Trypanosoma brucei

    International Nuclear Information System (INIS)

    Kaufmann, Doris; Gassen, Alwine; Maiser, Andreas; Leonhardt, Heinrich; Janzen, Christian J.

    2012-01-01

    Highlights: ► Characterization of the proliferating cell nuclear antigen in Trypanosoma brucei (TbPCNA). ► TbPCNA is a suitable marker to detect replication in T. brucei. ► TbPCNA distribution and regulation is different compared to closely related parasites T. cruzi and Leishmania donovani. -- Abstract: As in most eukaryotic cells, replication is regulated by a conserved group of proteins in the early-diverged parasite Trypanosoma brucei. Only a few components of the replication machinery have been described in this parasite and regulation, sub-nuclear localization and timing of replication are not well understood. We characterized the proliferating cell nuclear antigen in T. brucei (TbPCNA) to establish a spatial and temporal marker for replication. Interestingly, PCNA distribution and regulation is different compared to the closely related parasites Trypanosoma cruzi and Leishmania donovani. TbPCNA foci are clearly detectable during S phase of the cell cycle but in contrast to T. cruzi they are not preferentially located at the nuclear periphery. Furthermore, PCNA seems to be degraded when cells enter G2 phase in T. brucei suggesting different modes of replication regulation or functions of PCNA in these closely related eukaryotes.

  4. [Esophageal motor disorders in asymptomatic subjects with Trypanosoma cruzi infection].

    Science.gov (United States)

    Torres-Aguilera, M; Remes-Troche, J M; Roesch-Dietlen, F; Vázquez-Jiménez, J G; De la Cruz-Patiño, E; Grube-Pagola, P; Ruiz-Juárez, I

    2011-01-01

    The indeterminate chronic or "asymptomatic" phase of Trypanosoma cruzi (Chagas' disease) infection is characterized by the absence of gastrointestinal symptoms, and has an estimated duration of 20 to 30 years. However, the intramural denervation that induces dysfunction of the gastrointestinal tract is progressive. Recently, epidemiological studies have shown that the seroprevalence for this infection in our area ranges between 2% and 3% of the population. To detect the presence of esophageal motor disorders in asymptomatic individuals chronically infected with Trypanosoma cruzi using standard esophageal manometry. A cross sectional study in 28 asymptomatic subjects (27 men, age 40.39 ± 10.79) with serological evidence of infection with Trypanosoma cruzi was performed. In all cases demographic characteristics, gastrointestinal symptoms and esophageal motility disorders using conventional manometry were analyzed. In this study 54% (n = 15) of asymptomatic subjects had an esophageal motor disorder: 5 (18%) had nutcracker esophagus, 5 (18%) nonspecific esophageal motor disorders, 3 (11%) hypertensive lower esophageal sphincter (LES), 1 (4%) an incomplete relaxation of the LES and 1 (4%) had chagasic achalasia. More than half of patients that course with Chagas' disease in the indeterminate phase and that are apparently asymptomatic have impaired esophageal motility. Presence of hypertensive LES raises the possibility that this alteration represents an early stage in the development of chagasic achalasia.

  5. Regulation and spatial organization of PCNA in Trypanosoma brucei

    Energy Technology Data Exchange (ETDEWEB)

    Kaufmann, Doris; Gassen, Alwine [University of Munich (LMU), Department Biology I, Genetics, Grosshaderner Str. 2-4, 82152 Martinsried (Germany); Maiser, Andreas; Leonhardt, Heinrich [University of Munich (LMU), Department Biology II, Grosshaderner Str. 2-4, 82152 Martinsried (Germany); Janzen, Christian J., E-mail: christian.janzen@uni-wuerzburg.de [University of Munich (LMU), Department Biology I, Genetics, Grosshaderner Str. 2-4, 82152 Martinsried (Germany)

    2012-03-23

    Highlights: Black-Right-Pointing-Pointer Characterization of the proliferating cell nuclear antigen in Trypanosoma brucei (TbPCNA). Black-Right-Pointing-Pointer TbPCNA is a suitable marker to detect replication in T. brucei. Black-Right-Pointing-Pointer TbPCNA distribution and regulation is different compared to closely related parasites T. cruzi and Leishmania donovani. -- Abstract: As in most eukaryotic cells, replication is regulated by a conserved group of proteins in the early-diverged parasite Trypanosoma brucei. Only a few components of the replication machinery have been described in this parasite and regulation, sub-nuclear localization and timing of replication are not well understood. We characterized the proliferating cell nuclear antigen in T. brucei (TbPCNA) to establish a spatial and temporal marker for replication. Interestingly, PCNA distribution and regulation is different compared to the closely related parasites Trypanosoma cruzi and Leishmania donovani. TbPCNA foci are clearly detectable during S phase of the cell cycle but in contrast to T. cruzi they are not preferentially located at the nuclear periphery. Furthermore, PCNA seems to be degraded when cells enter G2 phase in T. brucei suggesting different modes of replication regulation or functions of PCNA in these closely related eukaryotes.

  6. Resposta imune-humoral e proteinogramas séricos de bovinos naturalmente infectados pelo Trypanosoma vivax

    OpenAIRE

    Sampaio, Paulo Henrique [UNESP

    2013-01-01

    Em bovinos o protozoário Trypanosoma vivax causa enfermidade que pode levar à redução dos índices produtivos ou a morte do animal. O diagnóstico deste protozoário pode ser realizado por testes parasitológicos, sorológicos e moleculares. Entretanto estes testes não são capazes de fornecer prognóstico, indicar a fase da infecção e a responsividade ao tratamento instituído. Por outro lado, o proteinograma sérico pode fornecer tais informações. O objetivo do estudo foi determinar o perfil eletrof...

  7. Hemoparasites of the genus Trypanosoma (Kinetoplastida: Trypanosomatidae and hemogregarines in Anurans of the São Paulo and Mato Grosso do Sul States - Brazil

    Directory of Open Access Journals (Sweden)

    Denise D.M. Leal

    2009-06-01

    Full Text Available Wild animals are exposed to numerous pathogens, including hemoparasites. The Trypanosoma and hemogregarinegroup are frequently reported as parasites in anurans (frogs, tree frogs and toads. The identification of these hemoparasites is usually made through stage observation of their morphology in the peripheral blood of the host. There areno studies, however, based on the biological cycle of these hemoparasites. The objective of the present study was toevaluate the presence of hemogregarines and Trypanosoma spp. in anurans captured in the States of São Paulo andMato Grosso do Sul- Brazil and to perform the morphological and morphometric characterization of these hemoparasites. The species of anurans examined were: Dendropsophus nanus, D. minutus, Leptodactylus chaquensis L. podicipinus, L. labyrinthicus, L. fuscus, Bufo granulosus, B. schneideri, Phyllomedusa hypocondrialis, Trachicephalus venulosus, Scinax fuscovarius and Hypsiboas albopunctatus. Of the total of 40 animals studied, four (10%were positive for hemogregarines and eight (20% were positive for Trypanosoma spp. Hemogregarine gamontsshowed variable morphology and, in addition to intraerythrocytic forms, extraerythrocytic forms were also observed.Extremely different forms of Trypanosoma were observed, as described in the literature, with the broad and oval forms being the most common.Os animais silvestres estão expostos a inúmeros patógenos,dentre eles estão os hemoparasitas. Podem-se destacar espécies do gênero Trypanosoma e do grupo das hemogregarinas,que ocorrem com freqüência parasitando anuros (rãs, pererecas e sapos. Normalmente, a descrição destes hemoparasitas é feita através da morfologia dos estágios observados nosangue periférico do hospedeiro e as pesquisas sobre o ciclobiológico desses hemoparasitas são escassas. Os objetivos dopresente estudo foram avaliar a presença de hemogregarinas eTrypanosoma spp. em anuros capturados nos Estados de São Paulo e

  8. Mammalian cell invasion and intracellular trafficking by Trypanosoma cruzi infective forms

    Directory of Open Access Journals (Sweden)

    Renato A. Mortara

    2005-03-01

    Full Text Available Trypanosoma cruzi, the etiological agent of Chagas’ disease, occurs as different strains or isolates that may be grouped in two major phylogenetic lineages: T. cruzi I, associated with the sylvatic cycle and T. cruzi II, linked to the human disease. In the mammalian host the parasite has to invade cells and many studies implicated the flagellated trypomastigotes in this process. Several parasite surface components and some of host cell receptors with which they interact have been identified. Our work focused on how amastigotes, usually found growing in the cytoplasm, can invade mammalian cells with infectivities comparable to that of trypomastigotes. We found differences in cellular responses induced by amastigotes and trypomastigotes regarding cytoskeletal components and actin-rich projections. Extracellularly generated amastigotes of T. cruzi I strains may display greater infectivity than metacyclic trypomastigotes towards cultured cell lines as well as target cells that have modified expression of different classes of cellular components. Cultured host cells harboring the bacterium Coxiella burnetii allowed us to gain new insights into the trafficking properties of the different infective forms of T. cruzi, disclosing unexpected requirements for the parasite to transit between the parasitophorous vacuole to its final destination in the host cell cytoplasm.O agente etiológico da doença de Chagas, Trypanosoma cruzi, ocorre como cepas ou isolados que podem ser agrupados em duas grandes linhagens filogenéticas: T. cruzi I associada ao ciclo silvestre e T. cruzi II ligada à doençahumana. No hospedeiro mamífero o parasita tem que invadir células, e vários estudos relacionam as formas flageladas tripomastigotas neste processo. Diferentes componentes de superfície dos parasitas e alguns dos respectivos receptores foram identificados. Em nosso trabalho temos procurado compreender como amastigotas, que normalmente são encontrados crescendo

  9. Rational Design of a New Trypanosoma rangeli Trans-Sialidase for Efficient Sialylation of Glycans

    DEFF Research Database (Denmark)

    Jers, Carsten; Michalak, Malwina; Larsen, Dorte Møller

    2014-01-01

    This paper reports rational engineering of Trypanosoma rangeli sialidase to develop an effective enzyme for a potentially important type of reactivity: production of sialylated prebiotic glycans. The Trypanosoma cruzi trans-sialidase and the homologous T. rangeli sialidase has previously been use...

  10. Melophagus ovinus and Trypanosoma (Megatrypanum) melophagium in ovines in the State of Minas Gerais, Brasil

    OpenAIRE

    Costa, José Oswaldo; Lima, Walter dos Santos; Leite, Antonio César Rios; Guimarães, Marcos Pezzi; Torres, Liléia Diotaiuti

    1983-01-01

    Neste trabalho Melophagus ovinus é identificado pela primeira vez no Estado de Minas Gerais e Trypanosoma (Megatrypanum) melophagium tem sua primeira ocorrência registrada no Brasil.Melophagus ovinus is identified for the first time in Minas Gerais State and Trypanosoma (Megatrypanum) melophagium in Brazil.

  11. Perspectives on the Trypanosoma cruzi–host cell receptor interactions

    Science.gov (United States)

    Villalta, Fernando; Scharfstein, Julio; Ashton, Anthony W.; Tyler, Kevin M.; Guan, Fangxia; Mukherjee, Shankar; Lima, Maria F.; Alvarez, Sandra; Weiss, Louis M.; Huang, Huan; Machado, Fabiana S.

    2009-01-01

    Chagas disease is caused by the parasite Trypanosoma cruzi. The critical initial event is the interaction of the trypomastigote form of the parasite with host receptors. This review highlights recent observations concerning these interactions. Some of the key receptors considered are those for thromboxane, bradykinin, and for the nerve growth factor TrKA. Other important receptors such as galectin-3, thrombospondin, and laminin are also discussed. Investigation into the molecular biology and cell biology of host receptors for T. cruzi may provide novel therapeutic targets. PMID:19283409

  12. Trypanosoma sp. diversity in Amazonian bats (Chiroptera; Mammalia) from Acre State, Brazil.

    Science.gov (United States)

    Dos Santos, Francisco C B; Lisboa, Cristiane V; Xavier, Samanta C C; Dario, Maria A; Verde, Rair de S; Calouro, Armando M; Roque, André Luiz R; Jansen, Ana M

    2017-11-16

    Bats are ancient hosts of Trypanosoma species and their flying ability, longevity and adaptability to distinct environments indicate that they are efficient dispersers of parasites. Bats from Acre state (Amazon Biome) were collected in four expeditions conducted in an urban forest (Parque Zoobotânico) and one relatively more preserved area (Seringal Cahoeira) in Rio Branco and Xapuri municipalities. Trypanosoma sp. infection was detected by hemoculture and fresh blood examination. Isolated parasite species were identified by the similarity of the obtained DNA sequence from 18S rDNA polymerase chain reaction and reference strains. Overall, 367 bats from 23 genera and 32 species were examined. Chiropterofauna composition was specific to each municipality, although Artibeus sp. and Carollia sp. prevailed throughout. Trypanosoma sp. infection was detected in 85 bats (23·2%). The most widely distributed and prevalent genotypes were (in order) Trypanosoma cruzi TcI, T. cruzi marinkellei, Trypanosoma dionisii, T. cruzi TcIV and Trypanosoma rangeli. At least one still-undescribed Trypanosoma species was also detected in this study. The detection of T. cruzi TcI and TcIV (the ones associated with Chagas disease in Amazon biome) demonstrates the putative importance of these mammal hosts in the epidemiology of the disease in the Acre State.

  13. Effects of medicinal plant extracts on growth of Leishmania (L. amazonensis and Trypanosoma cruzi Efeito de extratos de plantas medicinais no crescimento de Leishmania (L. amazonensis e Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Patrícia Shima Luize

    2005-03-01

    Full Text Available This study describes the screening of extracts obtained from 19 species of plants used in Brazilian traditional medicine for treatment of a variety of diseases. The extracts were tested against axenic amastigote and promastigote forms of Leishmania (L. amazonensis, and epimastigote forms of Trypanosoma cruzi in vitro at a concentration of 100 mg/ml. Baccharis trimera, Cymbopogon citratus, Matricaria chamomilla, Mikania glomerata, Ocimum gratissimum, Piper regnellii, Prunus domestica, Psidium guajava, Sambucus canadensis, Stryphnodendron adstringens, Tanacetum parthenium, and Tanacetum vulgare showed significant effects against one or both parasites, with a percentage of growth inhibition between 49.5 and 99%. The extracts showed no cytotoxic effect on sheep erythrocytes. These medicinal plants may be sources of new compounds that are clinically active against L. amazonensis and T. cruzi.Este estudo descreve a triagem de extratos obtidos de 19 espécies de plantas usadas na medicina tradicional brasileira para o tratamento de várias doenças. Os extratos foram testados contra formas amastigota axênica e promastigota de Leishmania (L. amazonensis, e formas epimastigota de Trypanosoma cruzi in vitro na concentração de 100 mg/ml. Baccharis trimera, Cymbopogon citratus, Matricaria chamomilla, Mikania glomerata, Ocimum gratissimum, Piper regnellii, Prunus domestica, Psidium guajava, Sambucus canadensis, Stryphnodendron adstringens, Tanacetum parthenium, e Tanacetum vulgare apresentaram efeito significante contra um ou ambos parasitas, com a porcentagem de inibição de crescimento entre 49,5 e 99%. Os extratos não mostraram efeito citotóxico em hemácias de carneiro. Essas plantas medicinais podem ser fontes alternativas de novos compostos clinicamente ativos contra L. amazonensis e T. cruzi.

  14. Trypanosoma cruzi: Transporte de metabolitos esenciales obtenidos del hospedador Trypanosoma cruzi: Transport of essential metabolites acquired from the host

    Directory of Open Access Journals (Sweden)

    Claudio A. Pereira

    2008-10-01

    Full Text Available El Trypanosoma cruzi es el agente causal de la enfermedad de Chagas, endémica en Argentina y en toda América Latina. Presenta numerosas características metabólicas diferenciales respecto a sus hospedadores insectos y mamíferos. Algunas de estas diferencias fueron consecuencia de millones de años de adaptación al parasitismo en los cuales estos organismos protozoarios reemplazaron, a lo largo de su evolución, muchas rutas metabólicas de biosíntesis por sistemas de transporte de metabolitos desde el hospedador. En esta revisión se describen los avances en el conocimiento de los sistemas de transporte tanto bioquímicos como también de las moléculas involucradas en dichos procesos. Se aborda con especial énfasis los transportadores de aminoácidos y poliaminas de T. cruzi de la familia AAAP (Amino Acid/Auxin Permeases ya que parece ser exclusiva de los tripanosomátidos. Teniendo en cuenta que estas moléculas se encuentran completamente ausentes en mamíferos podrían ser consideradas como potenciales blancos contra el Trypanosoma cruzi.Trypanosoma cruzi is the etiological agent of Chagas disease, a disease endemic not only in Argentina but also in all of Latinamerica. T. cruzi presents several metabolic characteristics which are completely absent in its insect vectors and in mammalian hosts. Some of these differences were acquired after millions of years of adaptation to parasitism, during which this protozoan replaced many biosynthetic routes for transport systems. In the present review, we describe the advances in the knowledge of T. cruzi transport processes and the molecules involved. In particular, we focus on aminoacid and polyamine transporters from the AAAP family (Amino Acid/Auxin Permeases, because they seem to be exclusive transporters from trypanosomatids. Taking into account that these permeases are completely absent in mammals, they could be considered as a potential target against Trypanosoma cruzi.

  15. Morphological evidence by scanning electron microscopy of excretion of metacyclic forms of Trypanosoma cruzi in vector's urine

    Directory of Open Access Journals (Sweden)

    Rodrigo Zeledon

    1988-09-01

    Full Text Available Comparision by scanning electron microscopy (SEM of Trypanosoma cruzi flagellates attached to the cuticle of the rectal gland of infected Dipetalogaster maxima nymphs, showed marked differences before amd after feeding. Before feeding numerous metacyclic trypomastigotes were observed among the abundant epimastigotes that formed the carpet of flagellates. On the other hand, in insects that were allowed to urinate for 24 hours after a meal, the metacyclics were scarce,indicating that they had been detached by the urine flow. An asymetric type of cell division, probably originating both an epi-and a trypomastigote, was occasionally observed. The occurrence of swellings at different levels of the flagella of epimastigotes suggests that secondary sites of attachment may be common.Observando-se, em microscopia eletrônica de varedura, formas flageladas do Trypanosoma cruzi presas a cutícula da glândula retal de ninfas infectadas de Dipetalogaster maxima verificaram-se nítidas diferenças antes e depois da alimentação. Antes, viam-se numerosos tripomastigotas metacíclicos entre os abundantes epimastigotas que formavam o tapete de flagelados, ao passo que nos insetos que urinavam dentro das 24 horas após o repasto os metacíclicos eram raros, indicando que haviam sido desprendidos pelo fluxo urinário. Foi notado, as vezes, um tipo assimétrico de divisão celular, originando um epi e um tripomastigota. Nos flagelados dos epimastigotas a presença de dilatações a diferentes níveis sugere que lugares secundários de aderência podem ser comuns.

  16. Benznidazole induces in vitro anaerobic metabolism in Trypanosoma cruzi epimastigotes

    Directory of Open Access Journals (Sweden)

    Marina Clare Vinaud

    2017-11-01

    Full Text Available Objective: To determine the biochemical alterations of the energetic metabolism of Trypanosoma cruzi epimastigotes in vitro exposed to different concentrations of benzinidazole. Methods: Biochemical analyses were performed at 3, 6 (log phase, 9 and 12 (stationary phase days of culture. Parasites were exposed to five concentrations of benzinidazole. Glycolysis, tricarboxilic acid cycle and fatty acids oxidation pathways were quantified through chromatography. Glucose, urea and creatinine were quantified through spectrophotometric analysis. Results: Anaerobic fermentation and fatty acids oxidation were increased in the stationary phase of the culture. Benzinidazole at high concentrations induced anaerobic metabolism in the log phase of the culture while the parasites exposed to the lower concentrations preferred the citric acid cycle as energy production pathway. Benzinidazole did not influence on the proteins catabolism. Conclusions: It is possible to conclude that there are metabolic differences between evolutive forms of Trypanosoma cruzi and the main drug used for its treatment induces the anaerobic metabolism in the parasite, possibly impairing the mitochondrial pathways.

  17. Estudo sobre triatomíneos e reservatórios silvestres de Trypanosoma cruzi no estado do Paraná, Sul do Brasil. Resultados preliminares

    Directory of Open Access Journals (Sweden)

    Toledo Max Jean de Ornelas

    1997-01-01

    Full Text Available Em localidades da zona rural de cinco municípios da região noroeste do Paraná adultos e ninfas de Triatoma sordida foram capturados em 21 (41,2% de 51 unidades domiciliares pesquisadas. Foram capturados 154 exemplares de T. sordida e 2 Panstrongylus megistus. De 135 exemplares examinados 58 (43,0% apresentavam o Trypanosoma tipo cruzi. Constatou-se também a infecção em 57,1% (4/7 dos gambás (Didelphis sp examinados. O peridomicílio apresentou-se mais infestado que o intradomicílio, sendo a casa de madeira abandonada a construção mais freqüente (34,7% do total investigado e com maior taxa de infestação (53,9%. Os dados mostram um elevado índice de infestação da zona rural por espécies secundárias de triatomíneos com altas taxas de infecção por flagelados do tipo T. cruzi, em uma área endêmica para a doença de Chagas já em fase de vigilância epidemiológica.

  18. Visual genome-wide RNAi screening to identify human host factors required for Trypanosoma cruzi infection

    CSIR Research Space (South Africa)

    Genovesio, A

    2011-05-01

    Full Text Available The protozoan parasite Trypanosoma cruzi is the etiologic agent of Chagas disease, a neglected tropical infection that affects millions of people in the Americas. Current chemotherapy relies on only two drugs that have limited efficacy...

  19. In or out? On the tightness of glycosomal compartmentalization of metabolites and enzymes in Trypanosoma brucei

    NARCIS (Netherlands)

    Haanstra, Jurgen R.; Bakker, Barbara M.; Michels, Paul A. M.

    Trypanosomatids sequester large parts of glucose metabolism inside specialised peroxisomes, called glycosomes. Many studies have shown that correct glycosomal compartmentalization of glycolytic enzymes is essential for bloodstream-form Trypanosoma brucel. The recent finding of pore-forming

  20. Novel molecular mechanism for targeting the parasite Trypanosoma brucei with snake venom toxins

    DEFF Research Database (Denmark)

    Martos Esteban, Andrea; Laustsen, Andreas Hougaard; Carrington, Mark

    Trypanosoma brucei is a parasitic protozoan species capable to infecting insect vectors whose bite further produces African sleeping sickness inhuman beings. During parasites’extracellular lives in the mammalian host, its outer coat, mainly composedof Variable surface glycoproteins (VSGs)[2...

  1. Mosaic VSGs and the scale of Trypanosoma brucei antigenic variation.

    Directory of Open Access Journals (Sweden)

    James P J Hall

    Full Text Available A main determinant of prolonged Trypanosoma brucei infection and transmission and success of the parasite is the interplay between host acquired immunity and antigenic variation of the parasite variant surface glycoprotein (VSG coat. About 0.1% of trypanosome divisions produce a switch to a different VSG through differential expression of an archive of hundreds of silent VSG genes and pseudogenes, but the patterns and extent of the trypanosome diversity phenotype, particularly in chronic infection, are unclear. We applied longitudinal VSG cDNA sequencing to estimate variant richness and test whether pseudogenes contribute to antigenic variation. We show that individual growth peaks can contain at least 15 distinct variants, are estimated computationally to comprise many more, and that antigenically distinct 'mosaic' VSGs arise from segmental gene conversion between donor VSG genes or pseudogenes. The potential for trypanosome antigenic variation is probably much greater than VSG archive size; mosaic VSGs are core to antigenic variation and chronic infection.

  2. Parasite Genome Projects and the Trypanosoma cruzi Genome Initiative

    Directory of Open Access Journals (Sweden)

    Wim Degrave

    1997-11-01

    Full Text Available Since the start of the human genome project, a great number of genome projects on other "model" organism have been initiated, some of them already completed. Several initiatives have also been started on parasite genomes, mainly through support from WHO/TDR, involving North-South and South-South collaborations, and great hopes are vested in that these initiatives will lead to new tools for disease control and prevention, as well as to the establishment of genomic research technology in developing countries. The Trypanosoma cruzi genome project, using the clone CL-Brener as starting point, has made considerable progress through the concerted action of more than 20 laboratories, most of them in the South. A brief overview of the current state of the project is given

  3. Electron Microscopy Analysis of the Nucleolus of Trypanosoma cruzi

    Science.gov (United States)

    López-Velázquez, Gabriel; Hernández, Roberto; López-Villaseñor, Imelda; Reyes-Vivas, Horacio; Segura-Valdez, María De L.; Jiménez-García, Luis F.

    2005-08-01

    The nucleolus is the main site for synthesis and processing of ribosomal RNA in eukaryotes. In mammals, plants, and yeast the nucleolus has been extensively characterized by electron microscopy, but in the majority of the unicellular eukaryotes no such studies have been performed. Here we used ultrastructural cytochemical and immunocytochemical techniques as well as three-dimensional reconstruction to analyze the nucleolus of Trypanosoma cruzi, which is an early divergent eukaryote of medical importance. In T. cruzi epimastigotes the nucleolus is a spherical intranuclear ribonucleoprotein organelle localized in a relatively central position within the nucleus. Dense fibrillar and granular components but not fibrillar centers were observed. In addition, nuclear bodies resembling Cajal bodies were observed associated to the nucleolus in the surrounding nucleoplasm. Our results provide additional morphological data to better understand the synthesis and processing of the ribosomal RNA in kinetoplastids.

  4. Lysophosphatidylcholine: A Novel Modulator of Trypanosoma cruzi Transmission

    Science.gov (United States)

    Silva-Neto, Mário A. C.; Carneiro, Alan B.; Silva-Cardoso, Livia; Atella, Georgia C.

    2012-01-01

    Lysophosphatidylcholine is a bioactive lipid that regulates a large number of cellular processes and is especially present during the deposition and infiltration of inflammatory cells and deposition of atheromatous plaque. Such molecule is also present in saliva and feces of the hematophagous organism Rhodnius prolixus, a triatominae bug vector of Chagas disease. We have recently demonstrated that LPC is a modulator of Trypanosoma cruzi transmission. It acts as a powerful chemoattractant for inflammatory cells at the site of the insect bite, which will provide a concentrated population of cells available for parasite infection. Also, LPC increases macrophage intracellular calcium concentrations that ultimately enhance parasite invasion. Finally, LPC inhibits NO production by macrophages stimulated by live T. cruzi, and thus interferes with the immune system of the vertebrate host. In the present paper, we discuss the main signaling mechanisms that are likely used by such molecule and their eventual use as targets to block parasite transmission and the pathogenesis of Chagas disease. PMID:22132309

  5. First report of Trypanosoma vegrandis in koalas (Phascolarctos cinereus).

    Science.gov (United States)

    Barbosa, Amanda; Austen, Jill; Gillett, Amber; Warren, Kristin; Paparini, Andrea; Irwin, Peter; Ryan, Una

    2016-08-01

    The present study describes the first report of Trypanosoma vegrandis in koalas using morphology and sequence analysis of the 18S rRNA gene. The prevalence of T. vegrandis in koalas was 13.6% (6/44). It is likely that the small size of T. vegrandis (<10μm in length), coupled with the difficulties in amplifying DNA of this parasite in mixed infections using trypanosome generic primers, are the reason why this organism has not been identified in koalas until now. This study highlights the importance of further research comprising a larger sample size to determine the prevalence of T. vegrandis in koalas as well as its potential impacts upon this marsupial species' health. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Semisolid liver infusion tryptose supplemented with human urine allows growth and isolation of Trypanosoma cruzi and Trypanosoma rangeli clonal lineages

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    Emanuella Francisco Fajardo

    2016-06-01

    Full Text Available Abstract: INTRODUCTION This work shows that 3% (v/v human urine (HU in semisolid Liver Infusion Tryptose (SSL medium favors the growth of Trypanosoma cruzi and T. rangeli. METHODS Parasites were plated as individual or mixed strains on SSL medium and on SSL medium with 3% human urine (SSL-HU. Isolate DNA was analyzed using polymerase chain reaction (PCR and pulsed-field gel electrophoresis (PFGE. RESULTS SSL-HU medium improved clone isolation. PCR revealed that T. cruzi strains predominate on mixed-strain plates. PFGE confirmed that isolated parasites share the same molecular karyotype as parental cell lines. CONCLUSIONS SSL-HU medium constitutes a novel tool for obtaining T. cruzi and T. rangeli clonal lineages.

  7. Formas de cultura de Trypanosoma rotatorium Mayer, 1843: isolado da rã Leptodactylus ocellatus do Brasil Culture forms of T. rotatorum Mayer, 1843

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    Neize M. Pereira

    1973-01-01

    Full Text Available Os autores estudaram o comportamento "in vitro" do Trypanosoma encontrado nas rãs brasileiras, visando critérios adicionais na caracterização específica deste grupo. Utilizaram diferentes meios de cultura (NNN, Novy e Mac Neal, SNB 9 de Diamond 1954, Boné & Steinert, 1956 Boné & Parent 1963 e Halevy & Gisry 1964 no isolamento do Trypanosoma rotatorium encontrado com certa freqüência na rã Leptodactylus com larga distribuição na região Neotropical. Observamso que o comportamento do T. rotatorium das rãs desta região em meios de cultura mostra características bem diferentes daquelas observadas com tripanosomas de outras regiões, quer seja pela dificuldade de manutenção em subcultura, quer pelas formas de divisão desenvolvidas. Empregamos os mesmos meios de cultura utilizados nos isolamentos dos tripanosomas de rã da Europa e como pode ser visto no Quadro I os resultados obtidos com material da região Neotropical são concordantes, surgerindo, pelo menos uma variação dentro da espécie.Different culture media were employed to isolate T. rotatorium, a common parasite in the blood of brazilian frog Leptodactylus ocellatus. Although we have isolated the parasite in three different media (SNB-9, Boné Parent and Boné Steinert media, subcultures were not obtained. Theses facts confirm the results also pointed out by Machado 1911 with T. rotatorium from hosts collected in the same region. In accordance with the factes observed in the litterature (see table I in this work our results suggest an important difference between the T. rotatorium of neotropical region and that of the other regions, which are easily cultivated in subcultures. The culture forms present some differential aspects in T. rotatorium mainly by production of "Somatelas".

  8. Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429)

    DEFF Research Database (Denmark)

    More, Simon J.; Bøtner, Anette; Butterworth, Andrew

    2017-01-01

    Trypanosoma evansi infections (including Surra) have been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on the eligibility of T. evansi infections (including Surra) to be listed, Article 9...

  9. Kinetoplast adaptations in American strains from Trypanosoma vivax

    Energy Technology Data Exchange (ETDEWEB)

    Greif, Gonzalo [Unidad de Biología Molecular, Institut Pasteur de Montevideo (Uruguay); Rodriguez, Matías [Sección Biomatemática, Facultad de Ciencias, Universidad de la Republica (Uruguay); Reyna-Bello, Armando [Departamento de Ciencias de la Vida, Carrera en Ingeniería en Biotecnología, Universidad de las Fuerzas Armadas (Ecuador); Centro de Estudios Biomédicos y Veterinarios, Universidad Nacional Experimental Simón Rodríguez-IDECYT, Caracas (Venezuela, Bolivarian Republic of); Robello, Carlos [Unidad de Biología Molecular, Institut Pasteur de Montevideo (Uruguay); Departamento de Bioquímica, Facultad de Medicina, Universidad de la República Uruguay (Uruguay); Alvarez-Valin, Fernando, E-mail: falvarez@fcien.edu.uy [Sección Biomatemática, Facultad de Ciencias, Universidad de la Republica (Uruguay)

    2015-03-15

    Highlights: • American T. vivax strains exhibit a drastic process of mitochondrial genome degradation. • T. vivax mitochondrial genes have among the fastest evolutionary rates in eukaryotes. • High rates of kDNA evolution are associated with relaxation of selective constrains. • Relaxed selective pressures are the result of mechanical transmission. • The evolutionary strategy of T. vivax differs from that of T. brucei-species complex. - Abstract: The mitochondrion role changes during the digenetic life cycle of African trypanosomes. Owing to the low abundance of glucose in the insect vector (tsetse flies) the parasites are dependent upon a fully functional mitochondrion, capable of performing oxidative phosphorylation. Nevertheless, inside the mammalian host (bloodstream forms), which is rich in nutrients, parasite proliferation relies on glycolysis, and the mitochondrion is partially redundant. In this work we perform a comparative study of the mitochondrial genome (kinetoplast) in different strains of Trypanosoma vivax. The comparison was conducted between a West African strain that goes through a complete life cycle and two American strains that are mechanically transmitted (by different vectors) and remain as bloodstream forms only. It was found that while the African strain has a complete and apparently fully functional kinetoplast, the American T. vivax strains have undergone a drastic process of mitochondrial genome degradation, in spite of the recent introduction of these parasites in America. Many of their genes exhibit different types of mutations that are disruptive of function such as major deletions, frameshift causing indels and missense mutations. Moreover, all but three genes (A6-ATPase, RPS12 and MURF2) are not edited in the American strains, whereas editing takes place normally in all (editable) genes from the African strain. Two of these genes, A6-ATPase and RPS12, are known to play an essential function during bloodstream stage

  10. Kinetoplast adaptations in American strains from Trypanosoma vivax

    International Nuclear Information System (INIS)

    Greif, Gonzalo; Rodriguez, Matías; Reyna-Bello, Armando; Robello, Carlos; Alvarez-Valin, Fernando

    2015-01-01

    Highlights: • American T. vivax strains exhibit a drastic process of mitochondrial genome degradation. • T. vivax mitochondrial genes have among the fastest evolutionary rates in eukaryotes. • High rates of kDNA evolution are associated with relaxation of selective constrains. • Relaxed selective pressures are the result of mechanical transmission. • The evolutionary strategy of T. vivax differs from that of T. brucei-species complex. - Abstract: The mitochondrion role changes during the digenetic life cycle of African trypanosomes. Owing to the low abundance of glucose in the insect vector (tsetse flies) the parasites are dependent upon a fully functional mitochondrion, capable of performing oxidative phosphorylation. Nevertheless, inside the mammalian host (bloodstream forms), which is rich in nutrients, parasite proliferation relies on glycolysis, and the mitochondrion is partially redundant. In this work we perform a comparative study of the mitochondrial genome (kinetoplast) in different strains of Trypanosoma vivax. The comparison was conducted between a West African strain that goes through a complete life cycle and two American strains that are mechanically transmitted (by different vectors) and remain as bloodstream forms only. It was found that while the African strain has a complete and apparently fully functional kinetoplast, the American T. vivax strains have undergone a drastic process of mitochondrial genome degradation, in spite of the recent introduction of these parasites in America. Many of their genes exhibit different types of mutations that are disruptive of function such as major deletions, frameshift causing indels and missense mutations. Moreover, all but three genes (A6-ATPase, RPS12 and MURF2) are not edited in the American strains, whereas editing takes place normally in all (editable) genes from the African strain. Two of these genes, A6-ATPase and RPS12, are known to play an essential function during bloodstream stage

  11. Panstrongylus megistus em ecótopos artificiais de ilhas do Alto Rio Paraná

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    Guilherme Ana Lucia Falavigna

    2001-01-01

    Full Text Available Em resposta a denúncias de triatomíneos em ilhas do Alto Rio Paraná foram investigados 145 ecótopos artificiais e 4 (2,8% deles encontravam-se infestados: residência, "clube", ex-escola e monte de madeira. Foram analisados 17 de 35 P. megistus coletados; 12 (70,6% apresentavam-se infectados por Trypanosoma cruzi. Ave e roedor constituíram as fontes alimentares mais comuns. Todos os exames sorológicos (56 de humanos, 18 de cães e 10 de gatos foram negativos.

  12. Enzootic transmission of Trypanosoma cruzi and T. rangeli in the Federal District of Brazil Transmissão enzoótica de Trypanosoma cruzi e T. rangeli no Distrito Federal, Brasil

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    Rodrigo Gurgel-Gonçalves

    2004-04-01

    Full Text Available The Federal District of Brazil (DF lies within the Cerrado biome, where open shrubland (savannas is interspersed with riverside gallery forests and permanent swamps (veredas. Trypanosoma cruzi-infected native triatomines occur in the area, but the enzootic transmission of trypanosomatids remains poorly characterized. A parasitological survey involving sylvatic triatomines (166 Rhodnius neglectus collected from Mauritia flexuosa palms and small mammals (98 marsupials and 70 rodents, totaling 18 species was conducted in 18 sites (mainly gallery forests and veredas of the DF. Parasites were isolated, morphologically identified, and characterized by PCR of nuclear (mini-exon gene and kinetoplast DNA (kDNA. Six R. neglectus, seven Didelphis albiventris and one Akodon cursor were infected by trypanosomes; wild reservoir infection is documented for the first time in the DF. kDNA PCR detected T. cruzi in five R. neglectus and mini-exon gene PCR revealed T. cruzi I in isolates from D. albiventris. Parasites infecting one bug yielded T. rangeli KP1+ kDNA amplicons. In spite of the occurrence of T. cruzi-infected D. albiventris (an important wild and peridomestic reservoir and R. neglectus (a secondary vector displaying synanthropic behavior, a low-risk of human Chagas disease transmission could be expected in the DF, considering the low prevalence infection recorded in this work. The detection of T. rangeli KP1+ associated with R. neglectus in the DF widens the known range of this parasite in Brazil and reinforces the hypothesis of adaptation of T. rangeli populations (KP1+ and KP1- to distinct evolutionary Rhodnius lineages.O Distrito Federal (DF do Brasil está localizado no bioma Cerrado, um complexo de fisionomias savânicas incluindo matas de galeria e campos úmidos permanentes (veredas. Triatomíneos silvestres infectados por Trypanosoma cruzi ocorrem na área, mas a transmissão enzoótica de tripanossomatídeos permanece insuficientemente

  13. Natural infection of the sand fly Phlebotomus kazeruni by Trypanosoma species in Pakistan

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    Iwata Hiroyuki

    2010-02-01

    Full Text Available Abstract The natural infection of phlebotomine sand flies by Leishmania parasites was surveyed in a desert area of Pakistan where cutaneous leishmaniasis is endemic. Out of 220 female sand flies dissected, one sand fly, Phlebotomus kazeruni, was positive for flagellates in the hindgut. Analyses of cytochrome b (cyt b, glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH and small subunit ribosomal RNA (SSU rRNA gene sequences identified the parasite as a Trypanosoma species of probably a reptile or amphibian. This is the first report of phlebotomine sand flies naturally infected with a Trypanosoma species in Pakistan. The possible infection of sand flies with Trypanosoma species should be taken into consideration in epidemiological studies of vector species in areas where leishmaniasis is endemic.

  14. Trypanosoma cruzi strain TcIV infects raccoons from Illinois

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    Cailey Vandermark

    Full Text Available BACKGROUND The northern limits of Trypanosoma cruzi across the territory of the United States remain unknown. The known vectors Triatoma sanguisuga and T. lecticularia find their northernmost limits in Illinois; yet, earlier screenings of those insects did not reveal the presence of the pathogen, which has not been reported in vectors or reservoir hosts in this state. OBJECTIVES Five species of medium-sized mammals were screened for the presence of T. cruzi. METHODS Genomic DNA was isolated from heart, spleen and skeletal muscle of bobcats (Lynx rufus, n = 60, raccoons (Procyon lotor, n = 37, nine-banded armadillos (Dasypus novemcinctus, n = 5, Virginia opossums (Didelphis virginiana, n = 3, and a red fox (Vulpes vulpes. Infections were detected targeting DNA from the kinetoplast DNA minicircle (kDNA and satellite DNA (satDNA. The discrete typing unit (DTU was determined by amplifying two gene regions: the Spliced Leader Intergenic Region (SL, via a multiplex polymerase chain reaction, and the 24Sα ribosomal DNA via a heminested reaction. Resulting sequences were used to calculate their genetic distance against reference DTUs. FINDINGS 18.9% of raccoons were positive for strain TcIV; the rest of mammals tested negative. MAIN CONCLUSIONS These results confirm for the first time the presence of T. cruzi in wildlife from Illinois, suggesting that a sylvatic life cycle is likely to occur in the region. The analyses of sequences of SL suggest that amplicons resulting from a commonly used multiplex reaction may yield non-homologous fragments.

  15. Polyclonal antibodies for the detection of Trypanosoma cruzi circulating antigens.

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    Edith S Málaga-Machaca

    2017-11-01

    Full Text Available Detection of Trypanosoma cruzi antigens in clinical samples is considered an important diagnostic tool for Chagas disease. The production and use of polyclonal antibodies may contribute to an increase in the sensitivity of immunodiagnosis of Chagas disease.Polyclonal antibodies were raised in alpacas, rabbits, and hens immunized with trypomastigote excreted-secreted antigen, membrane proteins, trypomastigote lysate antigen and recombinant 1F8 to produce polyclonal antibodies. Western blot analysis was performed to determine specificity of the developed antibodies. An antigen capture ELISA of circulating antigens in serum, plasma and urine samples was developed using IgY polyclonal antibodies against T. cruzi membrane antigens (capture antibody and IgG from alpaca raised against TESA. A total of 33 serum, 23 plasma and 9 urine samples were analyzed using the developed test. Among serum samples, compared to serology, the antigen capture ELISA tested positive in 55% of samples. All plasma samples from serology positive subjects were positive in the antigen capture ELISA. All urine positive samples had corresponding plasma samples that were also positive when tested by the antigen capture ELISA.Polyclonal antibodies are useful for detection of circulating antigens in both the plasma and urine of infected individuals. Detection of antigens is direct evidence of the presence of the parasite, and could be a better surrogate of current infection status.

  16. Trypanosoma avium of raptors (Falconiformes): phylogeny and identification of vectors.

    Science.gov (United States)

    Votýpka, J; Oborník, M; Volf, P; Svobodová, M; Lukes, J

    2002-09-01

    Avian trypanosomes are widespread parasites of birds, the transmission of which remains mostly unclear, with various blood-sucking insects mentioned as possible vectors. A search for vectors of trypanosomes of sparrowhawk (Accipiter nisus), buzzard (Buteo buteo), lesser-spotted eagle (Aquila pomarina) and kestrel (Falco tinnunculus) was performed in Czech and Slovak Republics. Black flies (Eusimulium spp.), hippoboscid flies (Ornithomyia avicularia), mosquitoes (Culex pipiens pipiens) and biting midges (Culicoides spp.), trapped while attempting to feed on raptor nestlings, were found to contain trypanosomatids in their intestine. Trypanosomes from the raptors and blood-sucking insects were isolated, and their 18S rRNA sequences were used for species identification and for the inference of intra- and interspecific relationships. Together with the trypanosome isolated from a black fly, the bird trypanosomes formed a well-supported Trypanosoma avium clade. The isolates derived from hippoboscid flies and mosquitoes are most likely also avian trypanosomes infecting birds other than the studied raptors. Analysis of the kinetoplast, that has features characteristic for the avian trypanosomes (minicircle size; dimensions of the kinetoplast disc), provided further evidence for the identification of vectors. It is suggested that all trypanosomes isolated from raptors included in this study belong to the T. avium complex and are transmitted by the ornithophilic simuliids such as Eusimulium securiforme.

  17. [Trypanosoma cruzi in triatomines from Nuevo Leon, Mexico].

    Science.gov (United States)

    Molina-Garza, Zinnia Judith; Rosales-Encina, José Luis; Galaviz-Silva, Lucio; Molina-Garza, Daniel

    2007-01-01

    To determine the prevalence of Trypanosoma cruzi in triatomines from Nuevo León using the standardization of an improved enzyme-linked immunosorbent assay test. From July to September 2005, 52 triatomines were captured in General Terán, a municipality located in Nuevo León. They were analyzed using optical microscopy (OM) and a polymerase chain reaction (PCR), as standards of reference, to develop a technique for detecting the parasite using enzyme-linked immunosorbent assay (ELISA). Using OM and PCR, 31 triatomines were found to be positive and 21 negative. Using ELISA, 27 samples were identified as positive and 25 negative (specificity 100%, sensitivity 87%, negative predictive value 84%, and positive predictive value 100%). The prevalence of infected triatomines was 59.61% with OM and PCR, and 51.92% with ELISA. Our data confirm that the ELISA assay in triatomines is a fast, reliable and useful tool. Since it was possible to simultaneously analyze a large number of samples with high sensibility and specificity values, the ELISA test proves to be useful for new epidemiologic studies having a high number of vectors. It is also less expensive than PCR. It is therefore recommended for epidemiological and preventive surveillance programs as a first screening test before conducting a confirmatory test using PCR.

  18. Heterogeneous infectiousness in guinea pigs experimentally infected with Trypanosoma cruzi.

    Science.gov (United States)

    Castillo-Neyra, Ricardo; Borrini Mayorí, Katty; Salazar Sánchez, Renzo; Ancca Suarez, Jenny; Xie, Sherrie; Náquira Velarde, Cesar; Levy, Michael Z

    2016-02-01

    Guinea pigs are important reservoirs of Trypanosoma cruzi, the causative parasite of Chagas disease, and in the Southern Cone of South America, transmission is mediated mainly by the vector Triatoma infestans. Interestingly, colonies of Triatoma infestans captured from guinea pig corrals sporadically have infection prevalence rates above 80%. Such high values are not consistent with the relatively short 7-8 week parasitemic period that has been reported for guinea pigs in the literature. We experimentally measured the infectious periods of a group of T. cruzi-infected guinea pigs by performing xenodiagnosis and direct microscopy each week for one year. Another group of infected guinea pigs received only direct microscopy to control for the effect that inoculation by triatomine saliva may have on parasitemia in the host. We observed infectious periods longer than those previously reported in a number of guinea pigs from both the xenodiagnosis and control groups. While some guinea pigs were infectious for a short time, other "super-shedders" were parasitemic up to 22 weeks after infection, and/or positive by xenodiagnosis for a year after infection. This heterogeneity in infectiousness has strong implications for T. cruzi transmission dynamics and control, as super-shedder guinea pigs may play a disproportionate role in pathogen spread. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Crystal structure of arginine methyltransferase 6 from Trypanosoma brucei.

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    Chongyuan Wang

    Full Text Available Arginine methylation plays vital roles in the cellular functions of the protozoan Trypanosoma brucei. The T. brucei arginine methyltransferase 6 (TbPRMT6 is a type I arginine methyltransferase homologous to human PRMT6. In this study, we report the crystal structures of apo-TbPRMT6 and its complex with the reaction product S-adenosyl-homocysteine (SAH. The structure of apo-TbPRMT6 displays several features that are different from those of type I PRMTs that were structurally characterized previously, including four stretches of insertion, the absence of strand β15, and a distinct dimerization arm. The comparison of the apo-TbPRMT6 and SAH-TbPRMT6 structures revealed the fine rearrangements in the active site upon SAH binding. The isothermal titration calorimetry results demonstrated that SAH binding greatly increases the affinity of TbPRMT6 to a substrate peptide derived from bovine histone H4. The western blotting and mass spectrometry results revealed that TbPRMT6 methylates bovine histone H4 tail at arginine 3 but cannot methylate several T. brucei histone tails. In summary, our results highlight the structural differences between TbPRMT6 and other type I PRMTs and reveal that the active site rearrangement upon SAH binding is important for the substrate binding of TbPRMT6.

  20. Telomeric expression sites are highly conserved in Trypanosoma brucei.

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    Christiane Hertz-Fowler

    Full Text Available Subtelomeric regions are often under-represented in genome sequences of eukaryotes. One of the best known examples of the use of telomere proximity for adaptive purposes are the bloodstream expression sites (BESs of the African trypanosome Trypanosoma brucei. To enhance our understanding of BES structure and function in host adaptation and immune evasion, the BES repertoire from the Lister 427 strain of T. brucei were independently tagged and sequenced. BESs are polymorphic in size and structure but reveal a surprisingly conserved architecture in the context of extensive recombination. Very small BESs do exist and many functioning BESs do not contain the full complement of expression site associated genes (ESAGs. The consequences of duplicated or missing ESAGs, including ESAG9, a newly named ESAG12, and additional variant surface glycoprotein genes (VSGs were evaluated by functional assays after BESs were tagged with a drug-resistance gene. Phylogenetic analysis of constituent ESAG families suggests that BESs are sequence mosaics and that extensive recombination has shaped the evolution of the BES repertoire. This work opens important perspectives in understanding the molecular mechanisms of antigenic variation, a widely used strategy for immune evasion in pathogens, and telomere biology.

  1. Exosome secretion affects social motility in Trypanosoma brucei.

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    Dror Eliaz

    2017-03-01

    Full Text Available Extracellular vesicles (EV secreted by pathogens function in a variety of biological processes. Here, we demonstrate that in the protozoan parasite Trypanosoma brucei, exosome secretion is induced by stress that affects trans-splicing. Following perturbations in biogenesis of spliced leader RNA, which donates its spliced leader (SL exon to all mRNAs, or after heat-shock, the SL RNA is exported to the cytoplasm and forms distinct granules, which are then secreted by exosomes. The exosomes are formed in multivesicular bodies (MVB utilizing the endosomal sorting complexes required for transport (ESCRT, through a mechanism similar to microRNA secretion in mammalian cells. Silencing of the ESCRT factor, Vps36, compromised exosome secretion but not the secretion of vesicles derived from nanotubes. The exosomes enter recipient trypanosome cells. Time-lapse microscopy demonstrated that cells secreting exosomes or purified intact exosomes affect social motility (SoMo. This study demonstrates that exosomes are delivered to trypanosome cells and can change their migration. Exosomes are used to transmit stress signals for communication between parasites.

  2. Meiosis and haploid gametes in the pathogen Trypanosoma brucei.

    Science.gov (United States)

    Peacock, Lori; Bailey, Mick; Carrington, Mark; Gibson, Wendy

    2014-01-20

    In eukaryote pathogens, sex is an important driving force in spreading genes for drug resistance, pathogenicity, and virulence. For the parasitic trypanosomes that cause African sleeping sickness, mating occurs during transmission by the tsetse vector and involves meiosis, but haploid gametes have not yet been identified. Here, we show that meiosis is a normal part of development in the insect salivary glands for all subspecies of Trypanosoma brucei, including the human pathogens. By observing insect-derived trypanosomes during the window of peak expression of meiosis-specific genes, we identified promastigote-like (PL) cells that interacted with each other via their flagella and underwent fusion, as visualized by the mixing of cytoplasmic red and green fluorescent proteins. PL cells had a short, wide body, a very long anterior flagellum, and either one or two kinetoplasts, but only the anterior kinetoplast was associated with the flagellum. Measurement of nuclear DNA contents showed that PL cells were haploid relative to diploid metacyclics. Trypanosomes are among the earliest diverging eukaryotes, and our results support the hypothesis that meiosis and sexual reproduction are ubiquitous in eukaryotes and likely to have been early innovations. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  3. mRNA localization mechanisms in Trypanosoma cruzi.

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    Lysangela R Alves

    Full Text Available Asymmetric mRNA localization is a sophisticated tool for regulating and optimizing protein synthesis and maintaining cell polarity. Molecular mechanisms involved in the regulated localization of transcripts are widespread in higher eukaryotes and fungi, but not in protozoa. Trypanosomes are ancient eukaryotes that branched off early in eukaryote evolution. We hypothesized that these organisms would have basic mechanisms of mRNA localization. FISH assays with probes against transcripts coding for proteins with restricted distributions showed a discrete localization of the mRNAs in the cytoplasm. Moreover, cruzipain mRNA was found inside reservosomes suggesting new unexpected functions for this vacuolar organelle. Individual mRNAs were also mobilized to RNA granules in response to nutritional stress. The cytoplasmic distribution of these transcripts changed with cell differentiation, suggesting that localization mechanisms might be involved in the regulation of stage-specific protein expression. Transfection assays with reporter genes showed that, as in higher eukaryotes, 3'UTRs were responsible for guiding mRNAs to their final location. Our results strongly suggest that Trypanosoma cruzi have a core, basic mechanism of mRNA localization. This kind of controlled mRNA transport is ancient, dating back to early eukaryote evolution.

  4. Trypanosoma cruzi. Surface antigens of blood and culture forms

    International Nuclear Information System (INIS)

    Nogueira, N.; Chaplan, S.; Tydings, J.D.; Unkeless, J.; Cohn, Z.

    1981-01-01

    The surface polypeptides of both cultured and blood forms of Trypanosoma cruzi were iodinated by the glucose oxidase-lactoperoxidase technique. Blood-form trypomastigotes (BFT) isolated form infected mice displayed a major 90,000-Mr component. In contrast, both epimastigotes and trypomastigotes obtained form acellular cultures expressed a smaller 75,000-Mr peptide. Both major surface components were presumably glycoproteins in terms of their binding to concanavalin A-Sepharose 4B. Within a 3-h period, both blood and culture forms synthesized their respective surface glycoproteins (90,000 Mr and 75,000 Mr, respectively in vitro. [/sub 35/S]methionine-labeled surface peptides were immunoprecipitated with immune sera of both human and murine origin. A panel of sera form patients with chronic Chagas' disease and hyperimmunized mice recognized similar surface peptides. These immunogens were the same components as the major iodinated species. The major BFT surface peptide was readily removed by trypsin treatment of the parasites, although the procedure did not affect the 75,000-Mr peptide from the culture forms. Two-dimensional polyacrylamide gel electrophoresis revealed that the 90,000-Mr peptide found on BFT was an acidic protein of isoelectric point (pI) 5.0, whereas, the 75,000-Mr peptide form culture-form trypomastigotes has a pI of 7.2. The 90,000-Mr component is thought to be responsible for the anti-phagocytic properties of the BFT

  5. Early Trypanosoma cruzi Infection Reprograms Human Epithelial Cells

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    María Laura Chiribao

    2014-01-01

    Full Text Available Trypanosoma cruzi, the causative agent of Chagas disease, has the peculiarity, when compared with other intracellular parasites, that it is able to invade almost any type of cell. This property makes Chagas a complex parasitic disease in terms of prophylaxis and therapeutics. The identification of key host cellular factors that play a role in the T. cruzi invasion is important for the understanding of disease pathogenesis. In Chagas disease, most of the focus is on the response of macrophages and cardiomyocytes, since they are responsible for host defenses and cardiac lesions, respectively. In the present work, we studied the early response to infection of T. cruzi in human epithelial cells, which constitute the first barrier for establishment of infection. These studies identified up to 1700 significantly altered genes regulated by the immediate infection. The global analysis indicates that cells are literally reprogrammed by T. cruzi, which affects cellular stress responses (neutrophil chemotaxis, DNA damage response, a great number of transcription factors (including the majority of NFκB family members, and host metabolism (cholesterol, fatty acids, and phospholipids. These results raise the possibility that early host cell reprogramming is exploited by the parasite to establish the initial infection and posterior systemic dissemination.

  6. Cancer in the parasitic protozoans Trypanosoma brucei and Toxoplasma gondii.

    Science.gov (United States)

    Lun, Zhao-Rong; Lai, De-Hua; Wen, Yan-Zi; Zheng, Ling-Ling; Shen, Ji-Long; Yang, Ting-Bo; Zhou, Wen-Liang; Qu, Liang-Hu; Hide, Geoff; Ayala, Francisco J

    2015-07-21

    Cancer is a general name for more than 100 malignant diseases. It is postulated that all cancers start from a single abnormal cell that grows out of control. Untreated cancers can cause serious consequences and deaths. Great progress has been made in cancer research that has significantly improved our knowledge and understanding of the nature and mechanisms of the disease, but the origins of cancer are far from being well understood due to the limitations of suitable model systems and to the complexities of the disease. In view of the fact that cancers are found in various species of vertebrates and other metazoa, here, we suggest that cancer also occurs in parasitic protozoans such as Trypanosoma brucei, a blood parasite, and Toxoplasma gondii, an obligate intracellular pathogen. Without treatment, these protozoan cancers may cause severe disease and death in mammals, including humans. The simpler genomes of these single-cell organisms, in combination with their complex life cycles and fascinating life cycle differentiation processes, may help us to better understand the origins of cancers and, in particular, leukemias.

  7. Production of amastigotes from metacyclic trypomastigotes of Trypanosoma cruzi

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    Víctor T Contreras

    2002-12-01

    Full Text Available Attempts to recreate all the developmental stages of Trypanosoma cruzi in vitro have thus far been met with partial success. It is possible, for instance, to produce trypomastigotes in tissue culture and to obtain metacyclic trypomastigotes in axenic conditions. Even though T. cruzi amastigotes are known to differentiate from trypomastigotes and metacyclic trypomastigotes, it has only been possible to generate amastigotes in vitro from the tissue-culture-derived trypomastigotes. The factors and culture conditions required to trigger the transformation of metacyclic trypomastigotes into amastigotes are as yet undetermined. We show here that pre-incubation of metacyclic trypomastigotes in culture (MEMTAU medium at 37°C for 48 h is sufficient to commit the parasites to the transformation process. After 72 h of incubation in fresh MEMTAU medium, 90% of the metacyclic parasites differentiate into forms that are morphologically indistinguishable from normal amastigotes. SDS-PAGE, Western blot and PAABS analyses indicate that the transformation of axenic metacyclic trypomastigotes to amastigotes is associated with protein, glycoprotein and antigenic modifications. These data suggest that (a T. cruzi amastigotes can be obtained axenically in large amounts from metacyclic trypomastigotes, and (b the amastigotes thus obtained are morphological, biological and antigenically similar to intracellular amastigotes. Consequently, this experimental system may facilitate a direct, in vitro assessment of the mechanisms that enable T. cruzi metacyclic trypomastigotes to transform into amastigotes in the cells of mammalian hosts.

  8. Geographical Distribution of Trypanosoma cruzi Genotypes in Venezuela

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    Carrasco, Hernán J.; Segovia, Maikell; Llewellyn, Martin S.; Morocoima, Antonio; Urdaneta-Morales, Servio; Martínez, Cinda; Martínez, Clara E.; Garcia, Carlos; Rodríguez, Marlenes; Espinosa, Raul; de Noya, Belkisyolé A.; Díaz-Bello, Zoraida; Herrera, Leidi; Fitzpatrick, Sinead; Yeo, Matthew; Miles, Michael A.; Feliciangeli, M. Dora

    2012-01-01

    Chagas disease is an endemic zoonosis native to the Americas and is caused by the kinetoplastid protozoan parasite Trypanosoma cruzi. The parasite is also highly genetically diverse, with six discrete typing units (DTUs) reported TcI – TcVI. These DTUs broadly correlate with several epidemiogical, ecological and pathological features of Chagas disease. In this manuscript we report the most comprehensive evaluation to date of the genetic diversity of T. cruzi in Venezuela. The dataset includes 778 samples collected and genotyped over the last twelve years from multiple hosts and vectors, including nine wild and domestic mammalian host species, and seven species of triatomine bug, as well as from human sources. Most isolates (732) can be assigned to the TcI clade (94.1%); 24 to the TcIV group (3.1%) and 22 to TcIII (2.8%). Importantly, among the 95 isolates genotyped from human disease cases, 79% belonged to TcI - a DTU common in the Americas, however, 21% belonged to TcIV- a little known genotype previously thought to be rare in humans. Furthermore, were able to assign multiple oral Chagas diseases cases to TcI in the area around the capital, Caracas. We discuss our findings in the context of T. cruzi DTU distributions elsewhere in the Americas, and evaluate the impact they have on the future of Chagas disease control in Venezuela. PMID:22745843

  9. The Oral Antimalarial Drug Tafenoquine Shows Activity against Trypanosoma brucei.

    Science.gov (United States)

    Carvalho, Luis; Martínez-García, Marta; Pérez-Victoria, Ignacio; Manzano, José Ignacio; Yardley, Vanessa; Gamarro, Francisco; Pérez-Victoria, José M

    2015-10-01

    The protozoan parasite Trypanosoma brucei causes human African trypanosomiasis, or sleeping sickness, a neglected tropical disease that requires new, safer, and more effective treatments. Repurposing oral drugs could reduce both the time and cost involved in sleeping sickness drug discovery. Tafenoquine (TFQ) is an oral antimalarial drug belonging to the 8-aminoquinoline family which is currently in clinical phase III. We show here that TFQ efficiently kills different T. brucei spp. in the submicromolar concentration range. Our results suggest that TFQ accumulates into acidic compartments and induces a necrotic process involving cell membrane disintegration and loss of cytoplasmic content, leading to parasite death. Cell lysis is preceded by a wide and multitarget drug action, affecting the lysosome, mitochondria, and acidocalcisomes and inducing a depolarization of the mitochondrial membrane potential, elevation of intracellular Ca(2+), and production of reactive oxygen species. This is the first report of an 8-aminoquinoline demonstrating significant in vitro activity against T. brucei. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  10. Anti-Trypanosoma cruzi antibody detection in eastern Andalusia (Spain).

    Science.gov (United States)

    Marín, Clotilde; Concha-Valdez, Fanny; Cañas, Rocío; Gutiérrez-Sánchez, Ramón; Sánchez-Moreno, Manuel

    2014-03-01

    Chagas disease caused by the protozoan haemoflagellate Trypanosoma cruzi is no longer found exclusively in Latin America; the disease is occurring in Europe, and Spain is the country with the highest prevalence. Our aim was to detect anti-T. cruzi antibodies in blood donors from southeast Spain, and we performed eight serological diagnostic assays on each of 550 blood samples collected in March-June 2010. Two in-house ELISA methods were used to test against a parasite lysate (ELISA-H) and the semi-purified superoxide dismutase excreted by T. cruzi (ELISA-SODe); we also used the Western blot technique against the same antigen (WB-SODe), indirect immunofluorescence (IFA) and four commercial tests. The serological test results showed a range of seroprevalence values, the lowest being 1.1%, determined by IFA and two commercial tests (Ab rapid and Chagascreen); other values were: 1.3% (commercial ELISA [Chagas ELISA IgG+IgM]); 2.1% (immunochromatographic test [Stick Chagas]); 2.7% (ELISA-H); 4.0% (WB-SODe); and 4.2%, the highest value (ELISA-SODe). The excellent specificity of SODe antigen for the detection of antibodies to T. cruzi in donors lead us to affirm that the serological test performed with this biomarker could provide a useful screening and confirmatory test method for cases of Chagas disease.

  11. Effects of azadirachtin on Rhodnius prolixus: immunity and trypanosoma interaction

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    Patricia de Azambuja

    1992-01-01

    Full Text Available The effects of azadirachtin, a tetranortriterpenoid from the neem tree Aradirachta indica J. on both immunity and Trypanosoma cruzi interaction within Rhodniusprolixus and other triatomines, were presented Given through a blood meal, azadirachtin affected the immune reactivity as shown by a significant reduction in numbers of hemocytes and consequently nodule formation follwing challenge with Enterobacter cloacae ß12, reduction in ability to produce antibacterial activities in the hemolymph when injected with bacteria, and decreased ability to destroy the infection caused by inoculation of E. cloacae cells. A single dose of azadirachtin was able to block the development of T. cruzi in R. prolixus if given through the meal at different intervals, together with, before or after parasite infection. Similary, these results were observed with different triatomine species and different strains of T. cruzi. Azadirachtin induced a permanent resistance of the vector against reinfection with T. cruzi. The significance of these data is discussed in relation to the general mode of azadirachtin action in insects.

  12. In vitro effects of citral on Trypanosoma cruzi metacyclogenesis

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    Josiane Cardoso

    2010-12-01

    Full Text Available Citral, the main constituent of lemongrass (Cymbopogon citratus essential oil, was added to Trypanosoma cruzi cultures grown in TAU3AAG medium to observe the effect on the epimastigote-to-trypomastigote differentiation process (metacyclogenesis. Our results showed that citral (20 μg/mL did not affect epimastigote viability or inhibit the differentiation process. Concentrations higher than 60 μg/mL, however, led to 100% cell death (both epimastigote and trypomastigote forms. Although epimastigotes incubated with 30 μg/mL citral were viable and able to adhere to the substrate, we observed around 50% inhibition in metacyclogenesis, with a calculated concentration that inhibited metacyclogenesis by 50% after 24 h (IC50/24 h of about 31 μg/mL. Treatment with 30 μg/mL citral did not hinder epimastigote multiplication because epimastigote growth resumed when treated cells were transferred to a drug-free liver infusion tryptose culture medium. Metacyclogenesis was almost totally abolished at 40 μg/mL after 24 h of incubation. Furthermore, the metacyclic trypomastigotes obtained in vitro were similarly susceptible to citral, with an IC50/24 h, concentration that killed 50% of the cells after 24 h, of about 24.5 μg/mL. Therefore, citral appears to be a good candidate as an inhibitory drug for further studies analyzing the T. cruzi metacyclogenesis process.

  13. Lysophosphatidylcholine: A Novel Modulator of Trypanosoma cruzi Transmission

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    Mário A. C. Silva-Neto

    2012-01-01

    Full Text Available Lysophosphatidylcholine is a bioactive lipid that regulates a large number of cellular processes and is especially present during the deposition and infiltration of inflammatory cells and deposition of atheromatous plaque. Such molecule is also present in saliva and feces of the hematophagous organism Rhodnius prolixus, a triatominae bug vector of Chagas disease. We have recently demonstrated that LPC is a modulator of Trypanosoma cruzi transmission. It acts as a powerful chemoattractant for inflammatory cells at the site of the insect bite, which will provide a concentrated population of cells available for parasite infection. Also, LPC increases macrophage intracellular calcium concentrations that ultimately enhance parasite invasion. Finally, LPC inhibits NO production by macrophages stimulated by live T. cruzi, and thus interferes with the immune system of the vertebrate host. In the present paper, we discuss the main signaling mechanisms that are likely used by such molecule and their eventual use as targets to block parasite transmission and the pathogenesis of Chagas disease.

  14. Seropositivity for Trypanosoma cruzi in domestic dogs from Sonora, Mexico.

    Science.gov (United States)

    Arce-Fonseca, Minerva; Carrillo-Sánchez, Silvia C; Molina-Barrios, Ramón M; Martínez-Cruz, Mariana; Cedillo-Cobián, Jesús R; Henao-Díaz, Yuly A; Rodríguez-Morales, Olivia

    2017-09-05

    Chagas disease is an important health problem in Latin America due to its incapacitating effects and associated mortality. Studies on seropositivity for Trypanosoma cruzi in Mexican dogs have demonstrated a direct correlation between seropositivity in humans and dogs, which can act as sentinels for the disease in this region. The objective of this study was to determine the seropositivity for T.cruzi infection in dogs from Sonora, a northern borderstate of Mexico. Responsible pet owners were selected at random from an urban area of Empalme municipality, Sonora, Mexico, and from there, 180 dog samples were collected. Anti-T. cruzi antibodies were determined using the enzyme-linked immunosorbent assay (ELISA) method. Reactive ELISA sera were processed by indirect immunofluorescence to confirm the presence of anti-T. cruzi antibodies. For the statistical analysis, chi-square tests were conducted. Dogs' sera showed a seropositivity rate of 4.44%. The rate of seropositivity was not associated with the dogs' age, sex, or socioeconomics pertaining to the geographical area. One sample (1/180, 0.55%) showed the acute state of the disease. The study found a presence of anti-T. cruzi antibodies in dogs in this area, which suggests vector transmission. There is a need for active surveillance programs throughout the state of Sonora and vector control strategies should also be implemented in endemic regions.

  15. Diterpenoids from Azorella compacta (Umbelliferae active on Trypanosoma cruzi

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    Araya Jorge E

    2003-01-01

    Full Text Available The anti-Trypanosoma cruzi activity of natural products isolated from Azorella compacta was evaluated, with particular emphasis on their effect against intracellular amastigotes. Five diterpenoids from A. compacta derived from mulinane and azorellane were isolated and identified. Only two products, named azorellanol (Y-2 and mulin-11,3-dien-20-oic acid (Y-5, showed trypanocidal activity against all stages of T. cruzi including intracellular amastigotes. At 10 µM, these compounds displayed a strong lytic activity. It ranged from 88.4 ± 0.6 to 99.0 ± 1 % for all strains and stages evaluate, with an IC50 /18 h values of 20-84 µM and 41-87 µM, respectively. The development of intracellular amastigotes was also inhibited by nearly 60% at 25 µM. The trypanocidal molecules Y-2 and Y-5 did show different degrees of cytotoxicity depending on the cell line tested, with an IC50 /24 h ranging from 33.2 to 161.2 µM. We evaluated the effect of diterpenoids against intracellular T. cruzi forms by immunofluorescent identification of a specific membrane molecular marker (Ssp-4 antigen of the T. cruzi amastigote forms. The accuracy and reproducibility of the measurements were found to be outstanding when examined by confocal microscopy.

  16. Prevalence of Trypanosoma cruzi/HIV coinfection in southern Brazil

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    Dulce Stauffert

    2017-03-01

    Full Text Available Chagas disease reactivation has been a defining condition for acquired immune deficiency syndrome in Brazil for individuals coinfected with Trypanosoma cruzi and HIV since 2004. Although the first coinfection case was reported in the 1980s, its prevalence has not been firmly established. In order to know coinfection prevalence, a cross-sectional study of 200 HIV patients was performed between January and July 2013 in the city of Pelotas, in southern Rio Grande do Sul, an endemic area for Chagas disease. Ten subjects were found positive for T. cruzi infection by chemiluminescence microparticle immunoassay and indirect immunofluorescence. The survey showed 5% coinfection prevalence among HIV patients (95% CI: 2.0–8.0, which was 3.8 times as high as that estimated by the Ministry of Health of Brazil. Six individuals had a viral load higher than 100,000 copies per μL, a statistically significant difference for T. cruzi presence. These findings highlight the importance of screening HIV patients from Chagas disease endemic areas.

  17. The activity of aminoglycoside antibiotics against Trypanosoma brucei.

    Science.gov (United States)

    Maina, N W; Kinyanjui, B; Onyango, J D; Auma, J E; Croj, S

    1998-01-01

    The trypanocidal activity of four aminoglycosides was determined against Trypanosoma brucei in vitro. The drug activity in descending order, was as follows; paromomycin kanamycin>gentamycin > neomycin. Paromomycin bad the highest activity and the concentration that inhibited 50% of trypanosome growth (IC50) was 11.4microM. The effect of paromomycin on the causative agents of the East African form of sleeping sickness - T.b. rhodesiense KETRI 265, 2285, 2545, 2562 and EATRO 110,112, 1152 was subsequently assessed. Variations sensitivities between the trypanosome populations were observed and IC50 values ranging from 13.01 to 43.06 microM recorded. However, when paromomycin was administered intraperitoneally (i.p) at 500 mg/kg, it was not effective in curing mice infected with T. b. rhodesienseKETRI 2545 the most drug-sensitive isolate in vitro. Lack of in vivo activity may be because the trypanosome is an extracellular parasite. The pharmacokinetics of paromomycin in the mouse model need to be determined.

  18. The morphology of ovine Trypanosoma melophagium (zoomastigophorea: kinetoplastida).

    Science.gov (United States)

    Büscher, G; Friedhoff, K T

    1984-02-01

    Morphologic and biometric data on bloodstream stages of Trypanosoma melophagium are presented. An increasing parasitemia with 111 trypomastigote stages of T. melophagium were found in Giemsa-stained thin blood smears taken from a splenectomized, cortisone-treated sheep recently infested with Melophagus ovinus infected with T. melophagium . The arithmetic mean and standard deviation in micron of the distances between posterior end and kinetoplast were 14.7 and 2.9, from the kinetoplastic to the center of the nucleus 5.1 and 1.1, and from there to the anterior end 19.5 and 1.9. The free flagellum measured 6.0 microns +/- 1.6 microns. The median and the range of the central 70% of values (median +/- 35%) of the nuclear index were 1.1 and 0.9-1.2 and of the kinetoplastic index 3.8 and 3.3-4.9. The same data in microns for the maximal width were 3.1 and 2.1-4.6, and for the width at the level of the nucleus 2.9 and 2.2-4.6. The larger and smaller diameters of the nucleus measured 2.6 (2.2-3.7) micron and 1.7 (1.3-1.7) micron, respectively. The corresponding kinetoplast diameters were 1.1 (0.9-1.3) microns and 0.9 (0.6-0.9) micron, respectively.

  19. Phenolic Constituents of Medicinal Plants with Activity against Trypanosoma brucei

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    Ya Nan Sun

    2016-04-01

    Full Text Available Neglected tropical diseases (NTDs affect over one billion people all over the world. These diseases are classified as neglected because they impact populations in areas with poor financial conditions and hence do not attract sufficient research investment. Human African Trypanosomiasis (HAT or sleeping sickness, caused by the parasite Trypanosoma brucei, is one of the NTDs. The current therapeutic interventions for T. brucei infections often have toxic side effects or require hospitalization so that they are not available in the rural environments where HAT occurs. Furthermore, parasite resistance is increasing, so that there is an urgent need to identify novel lead compounds against this infection. Recognizing the wide structural diversity of natural products, we desired to explore and identify novel antitrypanosomal chemotypes from a collection of natural products obtained from plants. In this study, 440 pure compounds from various medicinal plants were tested against T. brucei by in a screening using whole cell in vitro assays. As the result, twenty-two phenolic compounds exhibited potent activity against cultures of T. brucei. Among them, eight compounds—4, 7, 11, 14, 15, 18, 20, and 21—showed inhibitory activity against T. brucei, with IC50 values below 5 µM, ranging from 0.52 to 4.70 μM. Based on these results, we attempt to establish some general trends with respect to structure-activity relationships, which indicate that further investigation and optimization of these derivatives might enable the preparation of potentially useful compounds for treating HAT.

  20. Avaliação clínico-laboratorial de bovinos Nelore infectados experimentalmente com Trypanosoma vivax Clinical and laboratorial evaluation of Nellore cattle experimentally infected with Trypanosoma vivax

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    Maria A. M. Schenk

    2001-12-01

    Full Text Available Avaliaram-se as alterações clínico-laboratoriais de seis bezerros Nelore, de ambos os sexos, inoculados experimentalmente com 10(7 organismos viáveis de Trypanosoma vivax, isolados de bovinos da região de Poconé, Estado de Mato Grosso. Os animais foram observados diariamente, durante 30 dias, quanto aos parâmetros de temperatura retal, volume globular (VG, parasitemia, produção de anticorpos, coloração de mucosas, comportamento e apetite. Determinaram-se os níveis séricos de aspartato aminotransferase (AST, fosfatase alcalina (FA, gama glutamiltransferase (GGT, creatina kinase (CK, colesterol, uréia, creatinina, cálcio, fósforo e o perfil eletroforético das proteínas séricas aos 4, 8, 12, 16, 23 e 30 dias pós-inoculação (DPI. Durante os 6 meses seguintes, os animais foram observados semanalmente, avaliando-se a temperatura retal, o VG e a parasitemia. T. vivax foi evidenciado a partir do terceiro e quarto DPI em todos os bezerros e persistiu até o 30° DPI em cinco dos seis animais em estudo. Ocorreu um decréscimo significativo (pIn order to evaluate the clinical-laboratorial alterations, six Nellore calves were inoculated with 10(7 Trypanosoma vivax isolated from Poconé region, Mato Grosso, Brazil. The animals were evaluated daily for rectal temperature, packed cell volume (PCV, parasitemia, antibody production, color of mucous membranes, behavior and appetite. Blood and serum samples for biochemical evaluation for aspartate aminotransferase (AST, alkaline phosphatase (AF, gamma glutamyltransferase (GGT, cholesterol, urea, creatinine, creatine kinase (CK, calcium, phosphorus and proteinogram were collected on days 4, 8, 12, 16, 23 and 30 post inoculation (DPI. During the following 6 months rectal temperature, PCV and parasitemia were evaluated weekly. T. vivax was evidenced from 1 DPI in all calves and persisted until day 30 in five of six animals. A remarkable decrease (p<0.05 of PCV mean value (25% was observed on 10

  1. The regulation of autophagy differentially affects Trypanosoma cruzi metacyclogenesis.

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    María Cristina Vanrell

    2017-11-01

    Full Text Available Autophagy is a cellular process required for the removal of aged organelles and cytosolic components through lysosomal degradation. All types of eukaryotic cells from yeasts to mammalian cells have the machinery to activate autophagy as a result of many physiological and pathological situations. The most frequent stimulus of autophagy is starvation and the result, in this case, is the fast generation of utilizable food (e.g. amino acids and basic nutrients to maintain the vital biological processes. In some organisms, starvation also triggers other associated processes such as differentiation. The protozoan parasite Trypanosoma cruzi undergoes a series of differentiation processes throughout its complex life cycle. Although not all autophagic genes have been identified in the T. cruzi genome, previous works have demonstrated the presence of essential autophagic-related proteins. Under starvation conditions, TcAtg8, which is the parasite homolog of Atg8/LC3 in other organisms, is located in autophagosome-like vesicles. In this work, we have characterized the autophagic pathway during T. cruzi differentiation from the epimastigote to metacyclic trypomastigote form, a process called metacyclogenesis. We demonstrated that autophagy is stimulated during metacyclogenesis and that the induction of autophagy promotes this process. Moreover, with exception of bafilomycin, other classical autophagy modulators have similar effects on T. cruzi autophagy. We also showed that spermidine and related polyamines can positively regulate parasite autophagy and differentiation. We concluded that both polyamine metabolism and autophagy are key processes during T. cruzi metacyclogenesis that could be exploited as drug targets to avoid the parasite cycle progression.

  2. Protein 3-nitrotyrosine formation during Trypanosoma cruzi infection in mice

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    M. Naviliat

    2005-12-01

    Full Text Available Nitric oxide (·NO is a diffusible messenger implicated in Trypanosoma cruzi resistance. Excess production of ·NO and oxidants leads to the generation of nitrogen dioxide (·NO2, a strong nitrating agent. Tyrosine nitration is a post-translational modification resulting from the addition of a nitro (-NO2 group to the ortho-position of tyrosine residues. Detection of protein 3-nitrotyrosine is regarded as a marker of nitro-oxidative stress and is observed in inflammatory processes. The formation and role of nitrating species in the control and myocardiopathy of T. cruzi infection remain to be studied. We investigated the levels of ·NO and protein 3-nitrotyrosine in the plasma of C3H and BALB/c mice and pharmacologically modulated their production during the acute phase of T. cruzi infection. We also looked for protein 3-nitrotyrosine in the hearts of infected animals. Our results demonstrated that C3H animals produced higher amounts of ·NO than BALB/c mice, but their generation of peroxynitrite was not proportionally enhanced and they had higher parasitemias. While N G-nitro-arginine methyl ester treatment abolished ·NO production and drastically augmented the parasitism, mercaptoethylguanidine and guanido-ethyl disulfide, at doses that moderately reduced the ·NO and 3-nitrotyrosine levels, paradoxically diminished the parasitemia in both strains. Nitrated proteins were also demonstrated in myocardial cells of infected mice. These data suggest that the control of T. cruzi infection depends not only on the capacity to produce ·NO, but also on its metabolic fate, including the generation of nitrating species that may constitute an important element in parasite resistance and collateral myocardial damage.

  3. Targeted screening strategies to detect Trypanosoma cruzi infection in children.

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    Michael Z Levy

    2007-12-01

    Full Text Available Millions of people are infected with Trypanosoma cruzi, the causative agent of Chagas disease in Latin America. Anti-trypanosomal drug therapy can cure infected individuals, but treatment efficacy is highest early in infection. Vector control campaigns disrupt transmission of T. cruzi, but without timely diagnosis, children infected prior to vector control often miss the window of opportunity for effective chemotherapy.We performed a serological survey in children 2-18 years old living in a peri-urban community of Arequipa, Peru, and linked the results to entomologic, spatial and census data gathered during a vector control campaign. 23 of 433 (5.3% [95% CI 3.4-7.9] children were confirmed seropositive for T. cruzi infection by two methods. Spatial analysis revealed that households with infected children were very tightly clustered within looser clusters of households with parasite-infected vectors. Bayesian hierarchical mixed models, which controlled for clustering of infection, showed that a child's risk of being seropositive increased by 20% per year of age and 4% per vector captured within the child's house. Receiver operator characteristic (ROC plots of best-fit models suggest that more than 83% of infected children could be identified while testing only 22% of eligible children.We found evidence of spatially-focal vector-borne T. cruzi transmission in peri-urban Arequipa. Ongoing vector control campaigns, in addition to preventing further parasite transmission, facilitate the collection of data essential to identifying children at high risk of T. cruzi infection. Targeted screening strategies could make integration of diagnosis and treatment of children into Chagas disease control programs feasible in lower-resource settings.

  4. Sialic Acid Glycobiology Unveils Trypanosoma cruzi Trypomastigote Membrane Physiology.

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    Andrés B Lantos

    2016-04-01

    Full Text Available Trypanosoma cruzi, the flagellate protozoan agent of Chagas disease or American trypanosomiasis, is unable to synthesize sialic acids de novo. Mucins and trans-sialidase (TS are substrate and enzyme, respectively, of the glycobiological system that scavenges sialic acid from the host in a crucial interplay for T. cruzi life cycle. The acquisition of the sialyl residue allows the parasite to avoid lysis by serum factors and to interact with the host cell. A major drawback to studying the sialylation kinetics and turnover of the trypomastigote glycoconjugates is the difficulty to identify and follow the recently acquired sialyl residues. To tackle this issue, we followed an unnatural sugar approach as bioorthogonal chemical reporters, where the use of azidosialyl residues allowed identifying the acquired sugar. Advanced microscopy techniques, together with biochemical methods, were used to study the trypomastigote membrane from its glycobiological perspective. Main sialyl acceptors were identified as mucins by biochemical procedures and protein markers. Together with determining their shedding and turnover rates, we also report that several membrane proteins, including TS and its substrates, both glycosylphosphatidylinositol-anchored proteins, are separately distributed on parasite surface and contained in different and highly stable membrane microdomains. Notably, labeling for α(1,3Galactosyl residues only partially colocalize with sialylated mucins, indicating that two species of glycosylated mucins do exist, which are segregated at the parasite surface. Moreover, sialylated mucins were included in lipid-raft-domains, whereas TS molecules are not. The location of the surface-anchored TS resulted too far off as to be capable to sialylate mucins, a role played by the shed TS instead. Phosphatidylinositol-phospholipase-C activity is actually not present in trypomastigotes. Therefore, shedding of TS occurs via microvesicles instead of as a fully

  5. Prevalence of Trypanosoma vivax in cattle in central Sudan

    International Nuclear Information System (INIS)

    Fadl, M.; Babiker, H.I.; Bakheit, M.A.; A Rahman, A.H.

    2000-01-01

    The study was conducted to validate an antibody-detection ELISA test (Ab-ELISA) using pre-coated ELISA plates with crude antigen preparation of Trypanosoma vivax and to study the prevalence of T. vivax infection in central Sudan. A total of 704 blood samples were collected from cattle in central Sudan, a known endemic area of T. vivax infection. Additionally, 74 blood samples were collected from northern Sudan (Atbra town), an area presumed to be T. vivax-free. Sera were collected during the period September 1998 to May 1999 during three different seasons (summer, autumn and winter). Under the existing laboratory conditions, the test showed a clear distinction between different controls, i.e. strong positive control (C++), weak positive control (C+), negative control (C-) and the conjugate control (Cc). A percent positivity of 25% was taken as a cut-off value to determine the positivity or negativity of the test. The acceptable optical density range of strong positive control (C++) was 0.65-1.22. Lower and upper percent positivity limits for different controls were also determined. The study showed that T. vivax is endemic in central Sudan with 1.4% prevalence based on parasitological examination and 29.26% on Ab-ELISA. The infection rate was significantly higher during the autumn and winter than in summer. Young cattle showed significantly lower infection rates than adults as indicated by both the parasitological and the Ab-ELISA test. In relation to husbandry practice, migratory cattle showed significantly higher rates of prevalence than resident cattle. There was no significant difference in average packed red cell volume (PCV) values between ELISA positive and ELISA negative animals. Calves of less than one year of age showed significantly lower PCV values when belonging to migratory herds than to resident herds. (author)

  6. Congenital Trypanosoma cruzi Transmission in Santa Cruz, Bolivia

    Science.gov (United States)

    Bern, Caryn; Verastegui, Manuela; Gilman, Robert H.; LaFuente, Carlos; Galdos-Cardenas, Gerson; Calderon, Maritza; Pacori, Juan; Abastoflor, Maria del Carmen; Aparicio, Hugo; Brady, Mark F.; Ferrufino, Lisbeth; Angulo, Noelia; Marcus, Sarah; Sterling, Charles; Maguire, James H.

    2017-01-01

    Background We conducted a study of congenital Trypanosoma cruzi infection in Santa Cruz, Bolivia. Our objective was to apply new tools to identify weak points in current screening algorithms, and find ways to improve them. Methods Women presenting for delivery were screened by rapid and conventional serological tests. For infants of infected mothers, blood specimens obtained on days 0, 7, 21, 30, 90, 180, and 270 were concentrated and examined microscopically; serological tests were performed for the day 90, 180, and 270 specimens. Maternal and infant specimens, including umbilical tissue, were tested by polymerase chain reaction (PCR) targeting the kinetoplast minicircle and by quantitative PCR. Results Of 530 women, 154 (29%) were seropositive. Ten infants had congenital T. cruzi infection. Only 4 infants had positive results of microscopy evaluation in the first month, and none had positive cord blood microscopy results. PCR results were positive for 6 (67%) of 9 cord blood and 7 (87.5%) of 8 umbilical tissue specimens. PCR-positive women were more likely to transmit T. cruzi than were seropositive women with negative PCR results (P < .05). Parasite loads determined by quantitative PCR were higher for mothers of infected infants than for seropositive mothers of uninfected infants (P < .01). Despite intensive efforts, only 58% of at-risk infants had a month 9 specimen collected. Conclusions On the basis of the low sensitivity of microscopy in cord blood and high rate of loss to follow-up, we estimate that current screening programs miss one-half of all infected infants. Molecular techniques may improve early detection. PMID:19877966

  7. Functional characterization of 8-oxoguanine DNA glycosylase of Trypanosoma cruzi.

    Directory of Open Access Journals (Sweden)

    Carolina Furtado

    Full Text Available The oxidative lesion 8-oxoguanine (8-oxoG is removed during base excision repair by the 8-oxoguanine DNA glycosylase 1 (Ogg1. This lesion can erroneously pair with adenine, and the excision of this damaged base by Ogg1 enables the insertion of a guanine and prevents DNA mutation. In this report, we identified and characterized Ogg1 from the protozoan parasite Trypanosoma cruzi (TcOgg1, the causative agent of Chagas disease. Like most living organisms, T. cruzi is susceptible to oxidative stress, hence DNA repair is essential for its survival and improvement of infection. We verified that the TcOGG1 gene encodes an 8-oxoG DNA glycosylase by complementing an Ogg1-defective Saccharomyces cerevisiae strain. Heterologous expression of TcOGG1 reestablished the mutation frequency of the yeast mutant ogg1(-/- (CD138 to wild type levels. We also demonstrate that the overexpression of TcOGG1 increases T. cruzi sensitivity to hydrogen peroxide (H(2O(2. Analysis of DNA lesions using quantitative PCR suggests that the increased susceptibility to H(2O(2 of TcOGG1-overexpressor could be a consequence of uncoupled BER in abasic sites and/or strand breaks generated after TcOgg1 removes 8-oxoG, which are not rapidly repaired by the subsequent BER enzymes. This hypothesis is supported by the observation that TcOGG1-overexpressors have reduced levels of 8-oxoG both in the nucleus and in the parasite mitochondrion. The localization of TcOgg1 was examined in parasite transfected with a TcOgg1-GFP fusion, which confirmed that this enzyme is in both organelles. Taken together, our data indicate that T. cruzi has a functional Ogg1 ortholog that participates in nuclear and mitochondrial BER.

  8. Cynaropicrin targets the trypanothione redox system in Trypanosoma brucei.

    Science.gov (United States)

    Zimmermann, Stefanie; Oufir, Mouhssin; Leroux, Alejandro; Krauth-Siegel, R Luise; Becker, Katja; Kaiser, Marcel; Brun, Reto; Hamburger, Matthias; Adams, Michael

    2013-11-15

    In mice cynaropicrin (CYN) potently inhibits the proliferation of Trypanosoma brucei-the causative agent of Human African Trypanosomiasis-by a so far unknown mechanism. We hypothesized that CYNs α,β-unsaturated methylene moieties act as Michael acceptors for glutathione (GSH) and trypanothione (T(SH)2), the main low molecular mass thiols essential for unique redox metabolism of these parasites. The analysis of this putative mechanism and the effects of CYN on enzymes of the T(SH)2 redox metabolism including trypanothione reductase, trypanothione synthetase, glutathione-S-transferase, and ornithine decarboxylase are shown. A two step extraction protocol with subsequent UPLC-MS/MS analysis was established to quantify intra-cellular CYN, T(SH)2, GSH, as well as GS-CYN and T(S-CYN)2 adducts in intact T. b. rhodesiense cells. Within minutes of exposure to CYN, the cellular GSH and T(SH)2 pools were entirely depleted, and the parasites entered an apoptotic stage and died. CYN also showed inhibition of the ornithine decarboxylase similar to the positive control eflornithine. Significant interactions with the other enzymes involved in the T(SH)2 redox metabolism were not observed. Alongside many other biological activities sesquiterpene lactones including CYN have shown antitrypanosomal effects, which have been postulated to be linked to formation of Michael adducts with cellular nucleophiles. Here the interaction of CYN with biological thiols in a cellular system in general, and with trypanosomal T(SH)2 redox metabolism in particular, thus offering a molecular explanation for the antitrypanosomal activity is demonstrated. At the same time, the study provides a novel extraction and analysis protocol for components of the trypanosomal thiol metabolism. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Rab23 is a flagellar protein in Trypanosoma brucei

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    Field Mark C

    2011-06-01

    Full Text Available Abstract Background Rab small GTPases are important mediators of membrane transport, and orthologues frequently retain similar locations and functions, even between highly divergent taxa. In metazoan organisms Rab23 is an important negative regulator of Sonic hedgehog signaling and is crucial for correct development and differentiation of cellular lineages by virtue of an involvement in ciliary recycling. Previously, we reported that Trypanosoma brucei Rab23 localized to the nuclear envelope 1, which is clearly inconsistent with the mammalian location and function. As T. brucei is unicellular the potential that Rab23 has no role in cell signaling was possible. Here we sought to further investigate the role(s of Rab23 in T. brucei to determine if Rab23 was an example of a Rab protein with divergent function in distinct taxa. Methods/major findings The taxonomic distribution of Rab23 was examined and compared with the presence of flagella/cilia in representative taxa. Despite evidence for considerable secondary loss, we found a clear correlation between a conventional flagellar structure and the presence of a Rab23 orthologue in the genome. By epitope-tagging, Rab23 was localized and found to be present at the flagellum throughout the cell cycle. However, RNAi knockdown did not result in a flagellar defect, suggesting that Rab23 is not required for construction or maintenance of the flagellum. Conclusions The location of Rab23 at the flagellum is conserved between mammals and trypanosomes and the Rab23 gene is restricted to flagellated organisms. These data may suggest the presence of a Rab23-mediated signaling mechanism in trypanosomes.

  10. Comprehensive proteomic analysis of Trypanosoma cruzi epimastigote cell surface proteins by two complementary methods

    DEFF Research Database (Denmark)

    Queiroz, Rayner M L; Charneau, Sébastien; Motta, Flávia N

    2013-01-01

    Trypanosoma cruzi is a protozoan that causes Chagas' disease, a neglected infectious illness that affects millions of people, mostly in Latin America. Here, the cell surface subproteome of the T. cruzi epimastigote life form was characterized. In order to prepare samples enriched in epimastigote...

  11. Cell surface proteome analysis of human-hosted Trypanosoma cruzi life stages

    DEFF Research Database (Denmark)

    Queiroz, Rayner M L; Charneau, Sébastien; Bastos, Izabela M D

    2014-01-01

    Chagas' disease is a neglected infectious illness, caused by the protozoan Trypanosoma cruzi. It remains a challenging health issue in Latin America, where it is endemic, and so far there is no immunoprophylatic vaccine or satisfactory chemotherapic treatment for its chronic stage. The present work...

  12. Kinetic properties and inhibition of Trypanosoma cruzi 3-hydroxy-3-methylglutaryl CoA reductase

    DEFF Research Database (Denmark)

    Hurtado-Guerrrero, Ramón; Pena Diaz, Javier; Montalvetti, Andrea

    2002-01-01

    A detailed kinetic analysis of the recombinant soluble enzyme 3-hydroxy-3-methylglutaryl CoA reductase (HMGR) from Trypanosoma cruzi has been performed. The enzyme catalyzes the normal anabolic reaction and the reductant is NADPH. It also catalyzes the oxidation of mevalonate but at a lower propo...

  13. The effect of the diterpene 5-epi-icetexone on the cell cycle of Trypanosoma cruzi.

    NARCIS (Netherlands)

    Lozano, E.; Barrera, P.; Tonn, C.; Nieto, M.; Sartor, T.; Sosa, M.A.

    2012-01-01

    Numerous natural compounds have been used against Trypanosoma cruzi, the causative agent of Chagas' disease. Here, we studied the effect of the diterpene 5-epi-icetexone on growth and morphology of parasites synchronized with hydroxyurea, at different periods of time after removal of the nucleotide.

  14. Lack of evidence for integration of Trypanosoma cruzi minicircle DNA in South American human genomes

    Czech Academy of Sciences Publication Activity Database

    Flegontova, Olga; Lukeš, Julius; Flegontov, Pavel

    2012-01-01

    Roč. 42, č. 5 (2012), s. 437-441 ISSN 0020-7519 Grant - others:GA MŠk(CZ) LM2010005 Institutional support: RVO:60077344 Keywords : Trypanosoma cruzi * Kinetoplast minicircle * Chagas disease * Horizontal gene transfer * Human genome Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.637, year: 2012 http://www.sciencedirect.com/science/article/pii/S0020751912000781

  15. Analysis of the mitochondrial maxicircle of Trypanosoma lewisi, a neglected human pathogen

    Czech Academy of Sciences Publication Activity Database

    Lin, R.-H.; Lai, D.-H.; Zheng, L.-L.; Wu, J.; Lukeš, Julius; Hide, G.; Lun, Z.-R.

    2015-01-01

    Roč. 8, 30 December 2015 (2015), s. 665 ISSN 1756-3305 Institutional support: RVO:60077344 Keywords : Trypanosoma lewisi * Kinetoplast maxicircle * Mitochondrial DNA * RNA editing * Palindrome Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.234, year: 2015

  16. YCF45 protein, usually associated with plastids, is targeted into the mitochondrion of Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Týč, Jiří; Long, Shaojun; Jirků, Milan; Lukeš, Julius

    2010-01-01

    Roč. 173, č. 1 (2010), s. 43-47 ISSN 0166-6851 R&D Projects: GA ČR GA204/09/1667 Institutional research plan: CEZ:AV0Z60220518 Keywords : Trypanosoma * Plastid * Mitochondrion * Targeting * YCF45 * Horizontal gene transfer Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.875, year: 2010

  17. AcSDKP is down-regulated in anaemia induced by Trypanosoma ...

    African Journals Online (AJOL)

    We studied the responses of a tetrapeptide, AcSDKP, and IL-10, and their association with bone marrow nucleated cells in a Trypanosoma brucei brucei GVR35 experimental infection model. Methods Mouse infection was done intraperitoneally with 1 × 103 trypanosomes/mL. Mice were either infected or left uninfected (N ...

  18. Efficacy of some essential oils in mice infected with Trypanosoma cruzi

    African Journals Online (AJOL)

    Purpose: To evaluate the efficacy of orally administered Cymbopogon citratus, Zingiber officinale and Syzygium aromaticum essential oils (EOs) in mice infected with Trypanosoma cruzi. Methods: Three experiments were conducted with 48 Swiss mice each. The animals were inoculated with 2 x 106 metacyclic ...

  19. Molecular variation of Trypanosoma brucei subspecies as revealed by AFLP fingerprinting

    NARCIS (Netherlands)

    Agbo, E.E.C.; Majiwa, P.A.O.; Claassen, H.J.H.M.; Pas, te M.F.W.

    2002-01-01

    Genetic analysis of Trypanosoma spp. depends on the detection of variation between strains. We have used the amplified fragment length polymorphism (AFLP) technique to develop a convenient and reliable method for genetic characterization of Trypanosome (sub)species. AFLP accesses multiple

  20. Functions and cellular localization of cysteine desulfurase and selenocysteine lyase in Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Poliak, Pavel; Van Hoewyk, D.; Oborník, Miroslav; Zíková, Alena; Stuart, K. D.; Tachezy, J.; Pilon, M.; Lukeš, Julius

    2010-01-01

    Roč. 277, č. 2 (2010), s. 383-393 ISSN 1742-464X R&D Projects: GA ČR GA204/09/1667 Institutional research plan: CEZ:AV0Z60220518 Keywords : Fe–S cluster * mitochondrion * RNAi * selenoprotein * Trypanosoma Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.129, year: 2010

  1. The promoter for a variant surface glycoprotein gene expression site in Trypanosoma brucei

    NARCIS (Netherlands)

    Zomerdijk, J. C.; Ouellette, M.; ten Asbroek, A. L.; Kieft, R.; Bommer, A. M.; Clayton, C. E.; Borst, P.

    1990-01-01

    The variant-specific surface glycoprotein (VSG) gene 221 of Trypanosoma brucei is transcribed as part of a 60 kb expression site (ES). We have identified the promoter controlling this multigene transcription unit by the use of 221 chromosome-enriched DNA libraries and VSG gene 221 expression site

  2. Non-cytochrome mediated mitochondrial ATP production in bloodstream form Trypanosoma brucei brucei

    NARCIS (Netherlands)

    Bienen, E. J.; Maturi, R. K.; Pollakis, G.; Clarkson, A. B.

    1993-01-01

    The life cycle of Trypanosoma brucei brucei involves a series of differentiation steps characterized by marked changes in mitochondrial development and function. The bloodstream forms of this parasite completely lack cytochromes and have not been considered to have any Krebs cycle function. It has

  3. Procyclic Trypanosoma brucei do not use Krebs cycle activity for energy generation

    NARCIS (Netherlands)

    Weelden, van S.W.H.; Fast, B.; Vogt, A.; Meer, van der P.; Saas, J.; Hellemond, van J.J.; Tielens, A.G.M.; Boshart, M.

    2003-01-01

    The importance of a functional Krebs cycle for energy generation in the procyclic stage of Trypanosoma brucei was investigated under physiological conditions during logarithmic phase growth of a pleomorphic parasite strain. Wild type procyclic cells and mutants with targeted deletion of the gene

  4. Trypanocidal action of bisphosphonium salts through a mitochondrial target in bloodstream form Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Alkhaldi, A.A.M.; Martínek, Jan; Panicucci, Brian; Dardonville, C.; Zíková, Alena; de Koning, H.P.

    2016-01-01

    Roč. 6, č. 1 (2016), s. 23-34 ISSN 2211-3207 R&D Projects: GA MŠk LL1205 Institutional support: RVO:60077344 Keywords : Trypanosoma brucei * mitochondrion * FoF1 ATPase * succinate dehydrogenase * phosphonium salt * SDH complex Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.809, year: 2016

  5. Trypanosoma cruzi in the chicken model: Chagas-like heart disease in the absence of parasitism

    Czech Academy of Sciences Publication Activity Database

    Teixeira, A.R.L.; Gomes, C.; Nitz, N.; Sousa, A.O.; Alvez, R.M.; Guimaro, M.C.; Cordeiro, C.; Bernal, F.M.; Rosa, A.C.; Hejnar, Jiří; Leonardecz, E.; Hecht, M.M.

    2011-01-01

    Roč. 5, č. 3 (2011), e1000 ISSN 1935-2735 Institutional research plan: CEZ:AV0Z50520514 Keywords : Chagas disease * Trypanosoma cruzi * kDNA minicircles * inbred chicken Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.716, year: 2011

  6. Reprodutibilidade e estabilidade de antígenos preparados de culturas de Trypanosoma cruzi para reações de fixação do complemento

    Directory of Open Access Journals (Sweden)

    José Oliveira de Almeida

    1978-12-01

    Full Text Available Antígenos preparados de culturas de Trypanosoma cruzi foram experimentados com um sôro chagásico de referência, em reações quantitativas de fixação do complemento. Quatro deles foram liofilizados em pequenos volumes e mantidos em geladeira. Um outro foi mantido em estado líquido, com az ida sódica e a 3-6º C. Os títulos do complexo-imune, em termos de sôro ou de antígeno foram determinados como a inclinação da linha de regressão traçada quando se projetam as quantidades de complexo (em termos de sôro ou de antígeno necessárias para 50% de hemólise contra o número de unidades de complemento usadas na reação. Dividindo-se o título do antígeno pelo título do sôro, obtem-se um índice de reatividade específica (I.R.E., que informa sobre a reprodutibilidade e estabilidade do antígeno. Examinando os antígenos, de frascos colhidos ao acaso, verificou-se que os antígenos B.W. 89 e CDC 10-75 apresentaram um I.R.E. com pequena diferença entre as amostras, enquanto maior variação foi observada com os antígenos B.W. 105 e 760130. Antígenos reconstituídose mantidos em geladeira, até oito meses, perdiam lentamente sua capacidade reativa, com exceção do antígeno B.W. 89 e CDC 10-75. Os dados sugerem que o uso de antígenos de para reações de fixação do complemento devem ser empregados quando reconstituídos, evitando-se sua manutenção em estado líquido, pela queda do seu poder fixador.Antigens prepared from cultures of Trypanosoma cruzi were tested by the quantitative complemento fixation test, with a Chagasic reference serum. The titer was computed as the slope of the linear relatioship between antigen (or serum required for 50% hemolysis and the amount of complement present. When the antigen titer was divided by the serum titer, an index of specific reactivity was obtained. From the values of this index the reprodutibility of antigens was evaluated and also the decay of the capacity of the reativity against

  7. Mating compatibility in the parasitic protist Trypanosoma brucei.

    Science.gov (United States)

    Peacock, Lori; Ferris, Vanessa; Bailey, Mick; Gibson, Wendy

    2014-02-21

    Genetic exchange has been described in several kinetoplastid parasites, but the most well-studied mating system is that of Trypanosoma brucei, the causative organism of African sleeping sickness. Sexual reproduction takes place in the salivary glands (SG) of the tsetse vector and involves meiosis and production of haploid gametes. Few genetic crosses have been carried out to date and consequently there is little information about the mating compatibility of different trypanosomes. In other single-celled eukaryotes, mating compatibility is typically determined by a system of two or more mating types (MT). Here we investigated the MT system in T. brucei. We analysed a large series of F1, F2 and back crosses by pairwise co-transmission of red and green fluorescent cloned cell lines through experimental tsetse flies. To analyse each cross, trypanosomes were cloned from fly SG containing a mixture of both parents, and genotyped by microsatellites and molecular karyotype. To investigate mating compatibility at the level of individual cells, we directly observed the behaviour of SG-derived gametes in intra- or interclonal mixtures of red and green fluorescent trypanosomes ex vivo. Hybrid progeny were found in all F1 and F2 crosses and most of the back crosses. The success of individual crosses was highly variable as judged by the number of hybrid clones produced, suggesting a range of mating compatibilities among F1 progeny. As well as hybrids, large numbers of recombinant genotypes resulting from intraclonal mating (selfers) were found in some crosses. In ex vivo mixtures, red and green fluorescent trypanosome gametes were observed to pair up and interact via their flagella in both inter- and intraclonal combinations. While yellow hybrid trypanosomes were frequently observed in interclonal mixtures, such evidence of cytoplasmic exchange was rare in the intraclonal mixtures. The outcomes of individual crosses, particularly back crosses, were variable in numbers of both

  8. Diverse inhibitor chemotypes targeting Trypanosoma cruzi CYP51.

    Directory of Open Access Journals (Sweden)

    Shamila S Gunatilleke

    Full Text Available Chagas Disease, a WHO- and NIH-designated neglected tropical disease, is endemic in Latin America and an emerging infection in North America and Europe as a result of population moves. Although a major cause of morbidity and mortality due to heart failure, as well as inflicting a heavy economic burden in affected regions, Chagas Disease elicits scant notice from the pharmaceutical industry because of adverse economic incentives. The discovery and development of new routes to chemotherapy for Chagas Disease is a clear priority.The similarity between the membrane sterol requirements of pathogenic fungi and those of the parasitic protozoon Trypanosoma cruzi, the causative agent of Chagas human cardiopathy, has led to repurposing anti-fungal azole inhibitors of sterol 14α-demethylase (CYP51 for the treatment of Chagas Disease. To diversify the therapeutic pipeline of anti-Chagasic drug candidates we exploited an approach that included directly probing the T. cruzi CYP51 active site with a library of synthetic small molecules. Target-based high-throughput screening reduced the library of ∼104,000 small molecules to 185 hits with estimated nanomolar K(D values, while cross-validation against T. cruzi-infected skeletal myoblast cells yielded 57 active hits with EC(50 <10 µM. Two pools of hits partially overlapped. The top hit inhibited T. cruzi with EC(50 of 17 nM and was trypanocidal at 40 nM.The hits are structurally diverse, demonstrating that CYP51 is a rather permissive enzyme target for small molecules. Cheminformatic analysis of the hits suggests that CYP51 pharmacology is similar to that of other cytochromes P450 therapeutic targets, including thromboxane synthase (CYP5, fatty acid ω-hydroxylases (CYP4, 17α-hydroxylase/17,20-lyase (CYP17 and aromatase (CYP19. Surprisingly, strong similarity is suggested to glutaminyl-peptide cyclotransferase, which is unrelated to CYP51 by sequence or structure. Lead compounds developed by pharmaceutical

  9. Intraclonal mating occurs during tsetse transmission of Trypanosoma brucei

    Directory of Open Access Journals (Sweden)

    Ferris Vanessa

    2009-09-01

    Full Text Available Abstract Background Mating in Trypanosoma brucei is a non-obligatory event, triggered by the co-occurrence of different strains in the salivary glands of the vector. Recombinants that result from intra- rather than interclonal mating have been detected, but only in crosses of two different trypanosome strains. This has led to the hypothesis that when trypanosomes recognize a different strain, they release a diffusible factor or pheromone that triggers mating in any cell in the vicinity whether it is of the same or a different strain. This idea assumes that the trypanosome can recognize self and non-self, although there is as yet no evidence for the existence of mating types in T. brucei. Results We investigated intraclonal mating in T. b. brucei by crossing red and green fluorescent lines of a single strain, so that recombinant progeny can be detected in the fly by yellow fluorescence. For strain 1738, seven flies had both red and green trypanosomes in the salivary glands and, in three, yellow trypanosomes were also observed, although they could not be recovered for subsequent analysis. Nonetheless, both red and non-fluorescent clones from these flies had recombinant genotypes as judged by microsatellite and karyotype analyses, and some also had raised DNA contents, suggesting recombination or genome duplication. Strain J10 produced similar results indicative of intraclonal mating. In contrast, trypanosome clones recovered from other flies showed that genotypes can be transmitted with fidelity. When a yellow hybrid clone expressing both red and green fluorescent protein genes was transmitted, the salivary glands contained a mixture of fluorescent-coloured trypanosomes, but only yellow and red clones were recovered. While loss of the GFP gene in the red clones could have resulted from gene conversion, some of these clones showed loss of heterozygosity and raised DNA contents as in the other single strain transmissions. Our observations suggest

  10. The Complement System: A Prey of Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Kárita C. F. Lidani

    2017-04-01

    Full Text Available Trypanosoma cruzi is a protozoan parasite known to cause Chagas disease (CD, a neglected sickness that affects around 6–8 million people worldwide. Originally, CD was mainly found in Latin America but more recently, it has been spread to countries in North America, Asia, and Europe due the international migration from endemic areas. Thus, at present CD represents an important concern of global public health. Most of individuals that are infected by T. cruzi may remain in asymptomatic form all lifelong, but up to 40% of them will develop cardiomyopathy, digestive mega syndromes, or both. The interaction between the T. cruzi infective forms and host-related immune factors represents a key point for a better understanding of the physiopathology of CD. In this context, the complement, as one of the first line of host defense against infection was shown to play an important role in recognizing T. cruzi metacyclic trypomastigotes and in controlling parasite invasion. The complement consists of at least 35 or more plasma proteins and cell surface receptors/regulators, which can be activated by three pathways: classical (CP, lectin (LP, and alternative (AP. The CP and LP are mainly initiated by immune complexes or pathogen-associated molecular patterns (PAMPs, respectively, whereas AP is spontaneously activated by hydrolysis of C3. Once activated, several relevant complement functions are generated which include opsonization and phagocytosis of particles or microorganisms and cell lysis. An important step during T. cruzi infection is when intracellular trypomastigotes are release to bloodstream where they may be target by complement. Nevertheless, the parasite uses a sequence of events in order to escape from complement-mediated lysis. In fact, several T. cruzi molecules are known to interfere in the initiation of all three pathways and in the assembly of C3 convertase, a key step in the activation of complement. Moreover, T. cruzi promotes secretion

  11. Aspects of resistance to experimental infection with Trypanosoma cruzi

    International Nuclear Information System (INIS)

    Dias, Viviane Liotti

    2010-01-01

    Chagas disease, a zoonosis caused by the protozoan Trypanosoma cruzi, has a wide distribution in Latin America and extends from the southern part of the United States to Argentina. A number of 10 million of infected people is estimated and another 25 million exposed to the risk. Although discovered over a century, Chagas disease is still a serious infection that causes great socioeconomic impact, with no effective treatment at the chronic phase and in which, a lack of scientific knowledge can be observed. The main goal of this work was that obtaining and using consomic strain of mice, the resistance could be investigated. Consomic strains were produced by programmed mating, in which the animals were monitored with DNA polymorphic markers, and one of his chromosomes was replaced by his homologue from another strain. As parental, were used, the inbred strains C57BL/6/J Unib with resistant phenotype (donor) and as receiver, the A/JUnib strain, that has a susceptible phenotype. These models were used to produce five consomic strains: for the chromosomes 7 (CSs7), 11 (CSs11), 14 (CSs14), 17 (CSs17) and 19 (CSs19), described by Passos et al. (2003) as important in controlling infection caused by the Y strain of T. cruzi. In experimental testing, the consomics were inoculated intraperitoneally at doses of 10 1 , 10 2 , 10 3 and 10 4 using as control, animals from both parental lines. In all consomics, resistance was higher than that observed in the susceptible parental. In a second protocol, the consomics were mated with scheduled associations and the progenies were challenged with inocula employing increasing doses of trypomastigotes. The resistance observed in this group was also higher than that observed in the parental with susceptible phenotype. The observed results demonstrate that the use of the consomic strains that were produced order to assess the contribution of each chromosome in the resistance, as well as the effects of association between chromosomes are an

  12. Aspects of resistance to experimental infection with Trypanosoma cruzi; Aspectos da resistencia a infecao experimental com Trypanosoma cruzi

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Viviane Liotti

    2010-07-01

    Chagas disease, a zoonosis caused by the protozoan Trypanosoma cruzi, has a wide distribution in Latin America and extends from the southern part of the United States to Argentina. A number of 10 million of infected people is estimated and another 25 million exposed to the risk. Although discovered over a century, Chagas disease is still a serious infection that causes great socioeconomic impact, with no effective treatment at the chronic phase and in which, a lack of scientific knowledge can be observed. The main goal of this work was that obtaining and using consomic strain of mice, the resistance could be investigated. Consomic strains were produced by programmed mating, in which the animals were monitored with DNA polymorphic markers, and one of his chromosomes was replaced by his homologue from another strain. As parental, were used, the inbred strains C57BL/6/J Unib with resistant phenotype (donor) and as receiver, the A/JUnib strain, that has a susceptible phenotype. These models were used to produce five consomic strains: for the chromosomes 7 (CSs7), 11 (CSs11), 14 (CSs14), 17 (CSs17) and 19 (CSs19), described by Passos et al. (2003) as important in controlling infection caused by the Y strain of T. cruzi. In experimental testing, the consomics were inoculated intraperitoneally at doses of 10{sup 1}, 10{sup 2}, 10{sup 3} and 10{sup 4} using as control, animals from both parental lines. In all consomics, resistance was higher than that observed in the susceptible parental. In a second protocol, the consomics were mated with scheduled associations and the progenies were challenged with inocula employing increasing doses of trypomastigotes. The resistance observed in this group was also higher than that observed in the parental with susceptible phenotype. The observed results demonstrate that the use of the consomic strains that were produced order to assess the contribution of each chromosome in the resistance, as well as the effects of association between

  13. Molecular characterization and interactome analysis of Trypanosoma cruzi tryparedoxin II.

    Science.gov (United States)

    Arias, Diego G; Piñeyro, María Dolores; Iglesias, Alberto A; Guerrero, Sergio A; Robello, Carlos

    2015-04-29

    Trypanosoma cruzi, the causative agent of Chagas disease, possesses two tryparedoxins (TcTXNI and TcTXNII), belonging to the thioredoxin superfamily. TXNs are oxidoreductases which mediate electron transfer between trypanothione and peroxiredoxins. This constitutes a difference with the host cells, in which these activities are mediated by thioredoxins. These differences make TXNs an attractive target for drug development. In a previous work we characterized TcTXNI, including the redox interactome. In this work we extend the study to TcTXNII. We demonstrate that TcTXNII is a transmembrane protein anchored to the surface of the mitochondria and endoplasmic reticulum, with a cytoplasmatic orientation of the redox domain. It would be expressed during the metacyclogenesis process. In order to continue with the characterization of the redox interactome of T. cruzi, we designed an active site mutant TcTXNII lacking the resolving cysteine, and through the expression of this mutant protein and incubation with T. cruzi proteins, heterodisulfide complexes were isolated by affinity chromatography and identified by mass spectrometry. This allowed us to identify sixteen TcTXNII interacting proteins, which are involved in a wide range of cellular processes, indicating the relevance of TcTXNII, and contributing to our understanding of the redox interactome of T. cruzi. T. cruzi, the causative agent of Chagas disease, constitutes a major sanitary problem in Latin America. The number of estimated infected persons is ca. 8 million, 28 million people are at risk of infection and ~20,000 deaths occur per year in endemic regions. No vaccines are available at present, and most drugs currently in use were developed decades ago and show variable efficacy with undesirable side effects. The parasite is able to live and prolipherate inside macrophage phagosomes, where it is exposed to cytotoxic reactive oxygen and nitrogen species, derived from macrophage activation. Therefore, T. cruzi

  14. Characterization of plasma menbrane polypeptides of trypanosoma from bats Caracterização de polipeptídeos de membrana plasmática de tripanosomas de morcegos

    OpenAIRE

    R. T. Pinho; Giovanni de Simone

    1989-01-01

    Cell surface proteins of Trypanosoma dionisii, Trypanosoma vespertilionis and Trypanosoma sp. (M238) were radiodinated and their distribution both in the detergent-poor (DPP) and dertergent-enriched phase (DRP) was studied using a phase separation technique in Triton X-114 as well as polyacrylamide gel electrophoresis in sodium dodecyl sulphate (SDS-PAGE). Significant differences were observed in the proteins present in the DRP when the three species of trypanosoma were compared. Two major ba...

  15. A case of Trypanosoma congolense savannah type infection and its management in a dog

    Directory of Open Access Journals (Sweden)

    Peter Kimeli

    2014-12-01

    Full Text Available A case of Trypanosoma congolense savannah type infection in a 4-year old German shepherd dog weighing 26-kg was presented to the Small Animal Clinic, University of Nairobi, Kenya, with the history of anorexia and difficulty in breathing. The clinical manifestations were fever, pale mucous membrane, dyspnea and wasting. Blood examination revealed the existence of trypanosome parasites, and showed mild anemia. Internal Transcribed Spacer (ITS based polymerase chain reaction confirmed the presence of Trypanosoma congolense savannah type. Along with supporting therapy, the case was successfully managed using diminazene aceturate injection (dosed at 3.5 mg/kg body weight through intramuscular route. Complete recovery of the case was observed on day 6 of post-treatment.

  16. Anti-Trypanosoma cruzi and cytotoxic activities of Eugenia uniflora L.

    Science.gov (United States)

    Santos, Karla K A; Matias, Edinardo F F; Tintino, Saulo R; Souza, Celestina E S; Braga, Maria F B M; Guedes, Gláucia M M; Rolón, Miriam; Vega, Celeste; de Arias, Antonieta Rojas; Costa, José G M; Menezes, Irwin R A; Coutinho, Henrique D M

    2012-05-01

    Chagas disease is caused by Trypanosoma cruzi, being considered a public health problem. An alternative to combat this pathogen is the use of natural products isolated from fruits such as Eugenia uniflora, a plant used by traditional communities as food and medicine due to its antimicrobial and biological activities. Ethanolic extract from E. uniflora was used to evaluate in vitro anti-epimastigote and cytotoxic activity. This is the first record of anti-Trypanosoma activity of E. uniflora, demonstrating that a concentration presenting 50% of activity (EC(50)) was 62.76 μg/mL. Minimum inhibitory concentration (MIC) was ≤ 1024 μg/mL. Our results indicate that E. uniflora could be a source of plant-derived natural products with anti-epimastigote activity with low toxicity. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. The isolation and identification of Trypanosoma cruzi from raccoons in Maryland

    Science.gov (United States)

    Walton, B.C.; Bauman, P.M.; Diamond, L.S.; Herman, C.M.

    1958-01-01

    Five raccoons trapped at Patuxent Research Refuge, Laurel, Maryland, were found to have trypanosomes in the blood which were morphologically indistinguishable from Trypanosoma cruzi on stained smears. The organism grew well in culture. It developed and reproduced in Triatoma protracta, T. infestans, T. phyllosoma, and Rhodnius prolixus. Experimental infections were produced in raccoons, opossums, mice, rats, and monkeys by inoculation of blood, culture, and triatome forms. Typical leishmaniform bodies were found in tissue sections of cardiac muscle fibers from naturally and experimentally infected animals. Cross agglutinations carried out with Iiving cultural forms and rabbit antisera demonstrated a close antigenic relationship between the raccoon trypanosome and T. cruzi (Brazil strain). On the basis of (1) morphology, (2) presence of leishmaniform tissue stages, (3) development in triatomes, (4) infectivity to a variety of mammals, (5) culture characteristics, and (6) cross reactions in serological tests, this parasite is considered conspecific with Trypanosoma cruzi (Chagas, 1909), the causative agent of American human trypanosomiasis.

  18. Criopreservação de formas de cultura do Trypanosoma cruzi Cryopreservation of Trypanosoma cruzi culture form

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    Lúcia Maria C. Galvão

    1981-09-01

    Full Text Available Formas de cultura de diferentes cepas do T.cruzi foram submetidas a vários processos de criopreservação. As percentagens de recuperação, avaliadas pela motilidade dos parasitas, foram consideradas como adequadas com algumas das técnicas empregadas, variando entre 60 a 80%. A estabilidade das características biológicas do material criopreservado foi investigada através do estudo das curvas de crescimento e diferenciação em meio acelular, infectividade para celulas de cultura de tecido ("Vero", diferenciação intracelular em cultura de tecido assim como infectividade e curso da infecção em animais de laboratório. De um modo geral essas características nao foram significativamente alteradas no material congelado e estocado por diferentes períodos de tempo.A systematic study of the cryopreservation of T. cruzi culture forms was per formed using different parasite strains and freezing methods. The recovery rates with some of the methods as evaluated by motility of the thawed parasites were fairly high (60-80%. The following aspects have been used to investigate the stability of the parasites' biological characteristics atter cryopreservation: growth and differentiation in acelular medium, infectivity to tissue culture "Vero" cells, intracellular differentiation and infectivity to animals. Those characteristics had not been significantly changed by the cryopreservation procedures.

  19. Landscape epidemiology in urban environments: The example of rodent-borne Trypanosoma in Niamey, Niger.

    Science.gov (United States)

    Rossi, Jean-Pierre; Kadaouré, Ibrahima; Godefroid, Martin; Dobigny, Gauthier

    2017-10-05

    Trypanosomes are protozoan parasites found worldwide, infecting humans and animals. In the past decade, the number of reports on atypical human cases due to Trypanosoma lewisi or T. lewisi-like has increased urging to investigate the multiple factors driving the disease dynamics, particularly in cities where rodents and humans co-exist at high densities. In the present survey, we used a species distribution model, Maxent, to assess the spatial pattern of Trypanosoma-positive rodents in the city of Niamey. The explanatory variables were landscape metrics describing urban landscape composition and physiognomy computed from 8 land-cover classes. We computed the metrics around each data location using a set of circular buffers of increasing radii (20m, 40m, 60m, 80m and 100m). For each spatial resolution, we determined the optimal combination of feature class and regularization multipliers by fitting Maxent with the full dataset. Since our dataset was small (114 occurrences) we expected an important uncertainty associated to data partitioning into calibration and evaluation datasets. We thus performed 350 independent model runs with a training dataset representing a random subset of 80% of the occurrences and the optimal Maxent parameters. Each model yielded a map of habitat suitability over Niamey, which was transformed into a binary map implementing a threshold maximizing the sensitivity and the specificity. The resulting binary maps were combined to display the proportion of models that indicated a good environmental suitability for Trypanosoma-positive rodents. Maxent performed better with landscape metrics derived from buffers of 80m. Habitat suitability for Trypanosoma-positive rodents exhibited large patches linked to urban features such as patch richness and the proportion of landscape covered by concrete or tarred areas. Such inferences could be helpful in assessing areas at risk, setting of monitoring programs, public and medical staff awareness or even

  20. Genetic control of resistance to Trypanosoma brucei brucei infection in mice

    Czech Academy of Sciences Publication Activity Database

    Šíma, Matyáš; Havelková, Helena; Quan, L.; Svobodová, M.; Jarošíková, T.; Vojtíšková, Jarmila; Stassen, A. P. M.; Demant, P.; Lipoldová, Marie

    2011-01-01

    Roč. 5, č. 6 (2011), e1173 ISSN 1935-2735 R&D Projects: GA AV ČR IAA500520606; GA MŠk(CZ) LC06009 Grant - others:NIH-NCI(US) 1R01CA127162-01 Institutional research plan: CEZ:AV0Z50520514 Keywords : Trypanosoma brucei brucei * mouse recombinant congenic strains * Tbbr Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.716, year: 2011

  1. Genome and transcriptome studies of the protozoan parasites Trypanosoma cruzi and Giardia intestinalis

    OpenAIRE

    Franzén, Oscar

    2012-01-01

    Trypanosoma cruzi and Giardia intestinalis are two human pathogens and protozoan parasites responsible for the diseases Chagas disease and giardiasis, respectively. Both diseases cause su ering and illness in several million individuals. The former disease occurs primarily in South America and Central America, and the latter disease occurs worldwide. Current therapeutics are toxic and lack e cacy, and potential vaccines are far from the market. Increased knowledge about the bio...

  2. Population genetic analysis of Colombian Trypanosoma cruzi isolates revealed by enzyme electrophoretic profiles

    OpenAIRE

    Ruiz-Garcia, Manuel; Montilla, Marleny; Nicholls, Sebastian; Alvarez, Diana

    2001-01-01

    Although Colombia presents an enormous biological diversity, few studies have been conducted on the population genetics of Trypanosoma cruzi. This study was carried out with 23 Colombian stocks of this protozoa analyzed for 13 isoenzymatic loci. The Hardy-Weinberg equilibrium, the genetic diversity and heterogeneity, the genetic relationships and the possible spatial structure of these 23 Colombian stocks of T. cruzi were estimated. The majority of results obtained are in agreement with a clo...

  3. First Case of Natural Infection in Pigs: Review of Trypanosoma cruzi Reservoirs in Mexico

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    Paz María Salazar-Schettino

    1997-07-01

    Full Text Available An epidemiological research project was performed in the State of Morelos including collection of samples for blood smears and culture, serological tests, and xenodiagnoses from a total of 76 domestic and peridomestic mammals. Two strains of Trypanosoma cruzi were isolated by haemocultures; one from a pig (Sus scrofa, the first case of natural infection reported in Mexico, and the other from a dog (Canis familiaris. This study summarizes current information in Mexico concerning confirmed reservoirs of T. cruzi

  4. The import and function of diatom and plant frataxins in the mitochondrion of Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Long, Shaojun; Vávrová, Zuzana; Lukeš, Julius

    2008-01-01

    Roč. 162, č. 1 (2008), s. 100-104 ISSN 0166-6851 R&D Projects: GA AV ČR IAA500960705; GA MŠk LC07032; GA MŠk 2B06129; GA ČR GA204/06/1558 Institutional research plan: CEZ:AV0Z60220518 Keywords : frataxin * mitochondrion * Trypanosoma * diatom * evolutionary conservativeness * import Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.951, year: 2008

  5. DEAD-box RNA helicase is dispensable for mitochondrial translation in Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Richterová, Lenka; Vávrová, Zuzana; Lukeš, Julius

    2011-01-01

    Roč. 127, č. 1 (2011), 300-303 ISSN 0014-4894 R&D Projects: GA ČR GA204/09/1667; GA MŠk LC07032; GA MŠk 2B06129 Institutional research plan: CEZ:AV0Z60220518 Keywords : Trypanosoma * Mitochondrial translation * RNA helicase * Cytochrome c oxidase * Mitochondrion Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.122, year: 2011

  6. Mitochondrial fatty acid synthesis is required for normal mitochondrial morphology and function in Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Guler, J. L.; Kriegová, Eva; Smith, T. K.; Lukeš, Julius; Englund, P. T.

    2008-01-01

    Roč. 67, č. 5 (2008), s. 1125-1142 ISSN 0950-382X R&D Projects: GA ČR GA204/06/1558; GA MŠk LC07032; GA MŠk 2B06129 Grant - others:NIH(US) AI21334; Wellcome Trust(GB) 067441 Institutional research plan: CEZ:AV0Z60220518 Keywords : Trypanosoma * mitochondrion * fatty acid * RNA interference Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.213, year: 2008

  7. Disparate phenotypic effects from the knockdown of various Trypanosoma brucei cytochrome c oxidase subunits

    Czech Academy of Sciences Publication Activity Database

    Gnipová, Anna; Panicucci, Brian; Paris, Zdeněk; Verner, Zdeněk; Horváth, A.; Lukeš, Julius; Zíková, Alena

    2012-01-01

    Roč. 184, č. 2 (2012), s. 90-98 ISSN 0166-6851 R&D Projects: GA AV ČR KJB500960901; GA ČR GA204/09/1667 Institutional research plan: CEZ:AV0Z60220518 Keywords : Trypanosoma * RNA interference * Mitochondrion * Respiratory complexes * Cytochrome c oxidase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.734, year: 2012 http://www.sciencedirect.com/science/article/pii/S0166685112001065#

  8. A rapid method for testing in vivo the susceptibility of different strains of Trypanosoma cruzi to active chemotherapeutic agents

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    Leny S. Filardi

    1984-06-01

    Full Text Available A method is described which permits to determine in vivo an in a short period of time (4-6 hours the sensitivity of T. cruzo strains to known active chemotherapeutic agents. By using resistant- and sensitive T. cruzi stains 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 adminstration 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 infomation on the specific action against circulating trypomastigotes and screen active compounds. Differences in the natural susceptibility of Trypanosoma cruzi strains to active drugs have been already reported using different criteria, mostly demanding long-term study of the animal (Hauschka, 1949; Bock, Gonnert & Haberkorn, 1969; Brener, Costa & Chiari, 1976; Andrade & Figueira, 1977; Schlemper, 1982. In this paper we report a method which detects in 4-6 hours the effect of drugs on bloodstream forms in mice with established T. cruzi infections. The results obtained with this method show a fairly good correlation with those obtained by prolonged treatment schedules used to assess the action of drugs in experimental Chagas' disease and may be used to study the sensitivity of T. cruzi strains to active drugs.No presente trabalho descreve-se um metodo que permite determinar in vivo e em curto espaço de tempo (4-6 horas a sensibilidade de cepas de T. cruzi a agentes terapeuticos ativos na doença de Chagas. Usando-se cepas sensíveis e resistentes aos medicamentos foi possível observar uma boa correlação entre os resultados obtidos com o método rápido (que detecta atividade contra as formas circulantes do parasita e aqueles obtidos com esquema de acao prolongada que envolve a administração da droga por 20 dias e posterior avalia

  9. Exploring the Trypanosoma brucei Hsp83 potential as a target for structure guided drug design.

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    Juan Carlos Pizarro

    Full Text Available Human African trypanosomiasis is a neglected parasitic disease that is fatal if untreated. The current drugs available to eliminate the causative agent Trypanosoma brucei have multiple liabilities, including toxicity, increasing problems due to treatment failure and limited efficacy. There are two approaches to discover novel antimicrobial drugs--whole-cell screening and target-based discovery. In the latter case, there is a need to identify and validate novel drug targets in Trypanosoma parasites. The heat shock proteins (Hsp, while best known as cancer targets with a number of drug candidates in clinical development, are a family of emerging targets for infectious diseases. In this paper, we report the exploration of T. brucei Hsp83--a homolog of human Hsp90--as a drug target using multiple biophysical and biochemical techniques. Our approach included the characterization of the chemical sensitivity of the parasitic chaperone against a library of known Hsp90 inhibitors by means of differential scanning fluorimetry (DSF. Several compounds identified by this screening procedure were further studied using isothermal titration calorimetry (ITC and X-ray crystallography, as well as tested in parasite growth inhibitions assays. These experiments led us to the identification of a benzamide derivative compound capable of interacting with TbHsp83 more strongly than with its human homologs and structural rationalization of this selectivity. The results highlight the opportunities created by subtle structural differences to develop new series of compounds to selectively target the Trypanosoma brucei chaperone and effectively kill the sleeping sickness parasite.

  10. Developmental and Ultrastructural Characterization and Phylogenetic Analysis of Trypanosoma herthameyeri n. sp. of Brazilian Leptodactilydae Frogs.

    Science.gov (United States)

    Attias, Márcia; Sato, Lyslaine H; Ferreira, Robson C; Takata, Carmen S A; Campaner, Marta; Camargo, Erney P; Teixeira, Marta M G; de Souza, Wanderley

    2016-09-01

    We described the phylogenetic affiliation, development in cultures and ultrastructural features of a trypanosome of Leptodacylus chaquensis from the Pantanal biome of Brazil. In the inferred phylogeny, this trypanosome nested into the Anura clade of the basal Aquatic clade of Trypanosoma, but was separate from all known species within this clade. This finding enabled us to describe it as Trypanosoma herthameyeri n. sp., which also infects other Leptodacylus species from the Pantanal and Caatinga biomes. Trypanosoma herthameyeri multiplies as small rounded forms clumped together and evolving into multiple-fission forms and rosettes of epimastigotes released as long forms with long flagella; scarce trypomastigotes and glove-like forms are common in stationary-phase cultures. For the first time, a trypanosome from an amphibian was observed by field emission scanning electron microscopy, revealing a cytostome opening, well-developed flagellar lamella, and many grooves in pumpkin-like forms. Transmission electron microscopy showed highly developed Golgi complexes, relaxed catenation of KDNA, and a rich set of spongiome tubules in a regular parallel arrangement to the flagellar pocket as confirmed by electron tomography. Considering the basal position in the phylogenetic tree, developmental and ultrastructural data of T. herthameyeri are valuable for evolutionary studies of trypanosome architecture and cell biology. © 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.

  11. Evaluation of <em>HER2em> Gene Amplification in Breast Cancer Using Nuclei Microarray <em>in em>S>itu em>Hybridization

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    Xuefeng Zhang

    2012-05-01

    Full Text Available Fluorescence<em> em>>in situ em>hybridization (FISH assay is considered the “gold standard” in evaluating <em>HER2/neu (HER2em> gene status. However, FISH detection is costly and time consuming. Thus, we established nuclei microarray with extracted intact nuclei from paraffin embedded breast cancer tissues for FISH detection. The nuclei microarray FISH (NMFISH technology serves as a useful platform for analyzing <em>HER2em> gene/chromosome 17 centromere ratio. We examined <em>HER2em> gene status in 152 cases of invasive ductal carcinomas of the breast that were resected surgically with FISH and NMFISH. <em>HER2em> gene amplification status was classified according to the guidelines of the American Society of Clinical Oncology and College of American Pathologists (ASCO/CAP. Comparison of the cut-off values for <em>HER2em>/chromosome 17 centromere copy number ratio obtained by NMFISH and FISH showed that there was almost perfect agreement between the two methods (κ coefficient 0.920. The results of the two methods were almost consistent for the evaluation of <em>HER2em> gene counts. The present study proved that NMFISH is comparable with FISH for evaluating <em>HER2em> gene status. The use of nuclei microarray technology is highly efficient, time and reagent conserving and inexpensive.

  12. Tentativa de tratamento específico, por meio da ticlopidina, de pacientes com doença de Chagas em fase crônica

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    Rassi Anis

    2000-01-01

    Full Text Available Em investigação experimental, a ticlopidina mostrou ser ativa no sentido de diminuir a parasitemia e a mortalidade quando avaliada a infecção de camundongos pelo Trypanosoma cruzi. Por isso, este fármaco foi administrado a 12 pacientes com doença de Chagas, em fase crônica. Houve utilização de 150, 200 ou 250mg, durante 90 dias, conforme se tratasse de crianças, adolescentes ou adultos, respectivamente. Ficou documentado cabal insucesso sob os pontos de vista parasitológico e sorológico.

  13. Trypanocidal drugs for chronic asymptomatic Trypanosoma cruzi infection.

    Science.gov (United States)

    Villar, Juan Carlos; Perez, Juan Guillermo; Cortes, Olga Lucia; Riarte, Adelina; Pepper, Micah; Marin-Neto, Jose Antonio; Guyatt, Gordon H

    2014-05-27

    Prevention of chronic chagasic cardiomyopathy (CCC) by treating infected populations with trypanocidal therapy (TT) remains a challenge. Despite a renewed enthusiasm for TT, uncertainty regarding its efficacy, concerns about its safety and limited availability remain barriers for a wider use of conventional drugs. We have updated a previous version of this review. To systematically search, appraise, identify and extract data from eligible studies comparing the outcome of cohorts of seropositive individuals to Trypanosoma cruzi exposed to TT versus placebo or no treatment. We sought eligible studies in electronic databases (Cochrane Central Register of Controlled Trials (CENTRAL), Issue 1, 2014); MEDLINE (Ovid, 1946 to January week 5 2014); EMBASE (Ovid, 1980 to 2014 week 6) and LILACS (up to 6 May 2010)) by combining terms related with the disease and the treatment. The search also included a Google search, handsearch for references in review or selected articles, and search of expert files. We applied no language restrictions. Review authors screened the retrieved references for eligibility (those dealing with human participants treated with TT) and then assessed the pre-selected studies in full for inclusion. We included randomised controlled trials (RCTs) and observational studies that provided data on either mortality or clinical progression of CCC after at least four years of follow-up. Teams of two review authors independently carried out the study selection, data extraction and risk of bias assessment, with a referee resolving disagreement within the pairs. Data collection included study design, characteristics of the population and interventions or exposures and outcome measures. We defined categories of outcome data as parasite-related (positive serology, xenodiagnosis or polymerase chain reaction (PCR) after TT) and participant-related (including efficacy outcomes such as progression towards CCC, all-cause mortality and side effects of TT). We reported

  14. A New Natural Lactone from <em>Dimocarpus> <em>longan> Lour. Seeds

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    Zhongjun Li

    2012-08-01

    Full Text Available A new natural product named longanlactone was isolated from <em>Dimocarpus> <em>longan> Lour. seeds. Its structure was determined as 3-(2-acetyl-1<em>H>-pyrrol-1-yl-5-(prop-2-yn-1-yldihydrofuran-2(3H-one by spectroscopic methods and HRESIMS.

  15. Estudo do comportamento biológico de três amostras de trypanosoma cruzi isoladas de pacientes do instituto "dante pazzanese" de cardiologia

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    Vera Lúcia Pereira

    1987-06-01

    Full Text Available Foram estudadas três amostras de Trypanosoma cruzi isoladas de pacientes. As amostras foram observadas sob os seguintes parâmetros: níveis parasitêmicos, morfologia das formas sanguíneas, alterações histopatológicas, virulência e mortalidade em camundongos. A amostra IDPC-1 foi isolada de um paciente naturalmente infectado e tratado com benzonidazol. Provocou baixos índices parasitêmicos e mostrou baixa virulência, sendo que 83,4% dos animais evoluiram para a fase crônica. Os tripomastigotas eram de forma delgada, tornando-se largas ao final da fase aguda. Mostrou-se como miotrópica, pois as reações inflamatórias foram mais evidenciadas em células musculares persistindo ainda na fase crônica. A amostra IDPC-3 foi isolada anteriormente ao tratamento quimioterápico, de um paciente com infecção aguda por via transfusional. Causou altos níveis parasitêmicos e mostrou alta virulência com mortalidade total até o 12.° dia. As formas delgadas foram predominantes e foi caracterizada como retieulotrópica, por apresentar severa inflamação e parasitismo em linfonodos, baço e fígado A amostra IDPC-2 foi isolada de um paciente infectado por via transfusional, após o tratamento com três diferentes esquemas terapêuticos. Apresentou moderada virulência, com mortalidade total até o 17° dia e predominância de formas delgadas em todo decurso da infecção; contudo os índices parasitêmicos foram baixos. Houve uma severa reação inflamatória e parasitismo sistêmicos, porém mais evidenciados em células musculares, mostrando-se como miotrópica. Esta amostra apresentou comportamento biológico similar a IDPC-3, com pequenas divergências como baixos índices parasitêmicos e tendência ao miotropismo. Estes dados sugerem que amostras de T. cruzi isoladas de pacientes considerados fracasso terapêutico apresentam padrões de comportamento biológico similares a outras cepas já estudadas, porém provocam infecção menos

  16. Reference Gene Selection in the Desert Plant <em>Eremosparton songoricuem>m>

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    Dao-Yuan Zhang

    2012-06-01

    Full Text Available <em>Eremosparton songoricum em>(Litv. Vass. (<em>E. songoricumem> is a rare and extremely drought-tolerant desert plant that holds promise as a model organism for the identification of genes associated with water deficit stress. Here, we cloned and evaluated the expression of eight candidate reference genes using quantitative real-time reverse transcriptase polymerase chain reactions. The expression of these candidate reference genes was analyzed in a diverse set of 20 samples including various <em>E. songoricumem> plant tissues exposed to multiple environmental stresses. GeNorm analysis indicated that expression stability varied between the reference genes in the different experimental conditions, but the two most stable reference genes were sufficient for normalization in most conditions.<em> EsEFem> and <em>Esα-TUB> were sufficient for various stress conditions, <em>EsEF> and <em>EsACT> were suitable for samples of differing germination stages, and <em>EsGAPDH>and <em>Es>UBQ em>were most stable across multiple adult tissue samples. The <em>Es18Sem> gene was unsuitable as a reference gene in our analysis. In addition, the expression level of the drought-stress related transcription factor <em>EsDREB2em>> em>verified the utility of<em> E. songoricumem> reference genes and indicated that no single gene was adequate for normalization on its own. This is the first systematic report on the selection of reference genes in <em>E. songoricumem>, and these data will facilitate future work on gene expression in this species.

  17. Acute phase proteins: a potential approach for diagnosing chronic infection by Trypanosoma vivax Proteínas de fase aguda: uma possível abordagem para diagnóstico de infecção crônica por Trypanosoma vivax

    Directory of Open Access Journals (Sweden)

    Katyane de Sousa Almeida

    2012-06-01

    Full Text Available The present study aimed to assess potential changes in acute phase proteins in sheep experimentally infected with Trypanosoma vivax. There were studied eight male sheep, four used as controls and four infected with 10(5 T. vivax trypomastigotes. Blood samples were collected at two points times before infection and then at 5,7, 9, 11, 13, 15, 20, 30, 45, 60, 75, 90, 105 and 120 days post-infection (dpi. Blood samples were centrifuged and allotted, and acute phase proteins were then separated by electrophoresis on acrylamide gel containing sodium dodecyl sulfate. Protein concentrations were determined by computer-assisted densitometry. Total protein was determined by colorimetric biuret method. Trypanosomes were counted daily using a 5 mL aliquot of blood smear on a glass slide under a 22 × 22 mm coverslip. Parasites were counted in 100 microscopic fields (40× magnification, and then multiplied by a correction factor. The results were expressed as parasites per mL of blood. For statistical analyses, we used the Wilcoxon test at 5% significance level. There was found a reduction in several acute phase proteins and increase in antitrypsin and transferrin. This finding can be used for the diagnosis of T. vivax infection, especially in chronic infection.O objetivo do presente estudo foi verificar possíveis alterações nas proteínas de fase aguda em ovinos infectados experimentalmente com Trypanosoma vivax. Para tanto, foram utilizados oito ovinos machos, sendo quatro usados como controle e quatro infectados com 10(5 tripomastigotas de T. vivax. Colheram-se amostras de sangue em dois tempos antes da infecção e, posteriormente, aos 5, 7, 9, 11, 13, 15, 20, 30, 45, 60, 75, 90, 105 e 120 dias após a infecção (dpi; após centrifugação e aliquotização das amostras. As proteínas de fase aguda foram separadas por eletroforese em gel de acrilamida, contendo dodecil sulfato de sódio, e suas concentrações foram determinadas através de

  18. Utilización de Lepidium Peruvianum Maca, como medio de cultivo para el crecimiento de Trypanosoma Cruzi

    OpenAIRE

    Saldaña C, Charles; Córdova P, Ofelia; Vargas V¹, Franklin

    2006-01-01

    Por sus características nutritivas de alto valor, se ensayó la posible utilidad del Lepidium peruvianum maca, como un medio para cultivar Trypanosoma cruzi. Bajo condiciones experimentales se procedió a incubar epimastigotes de T. cruzi en cuatro medios de cultivo bifásicos diferentes, a base de Lepidium peruvianum maca, los cuales fueron comparados con el medio de cultivo BHI como control. La incorporación de maca como medio de cultivo permitió el crecimiento de Trypanosoma cruzi; se determi...

  19. Efecto inmunosupresor de la infección por Trypanosoma musculi (Mastigophora: Trypanosomatidae en la toxoplasmosis experimental Immunosuppressor effect of Trypanosoma musculi (Mastigophora: Trypanosomatidae on experimental toxoplasmosis

    Directory of Open Access Journals (Sweden)

    Loretta Piccolo-Johanning

    2013-06-01

    Full Text Available La prevalencia de infecciones por Toxoplasma gondii en el ser humano es de 5-90% según la zona geográfica; en Costa Rica por ejemplo, la seroprevalencia es de un 58%, por lo que es importante comprender algunos procesos inmunológicos, propios en estas afectaciones parasitarias. Con el objeto de determinar si el Trypanosoma musculi ejerce procesos de inmunosupresión sobre Toxoplasma gondii se realizó un experimento en el que se inocularon ratones Swiss con T. musculi cuatro, cinco, seis y siete días previos a la infección con T. gondii, ocurriendo la inmunosupresión cuando la inoculación con T. musculi fue hecha cuatro días antes. Además, la cantidad de tripomastigotos inoculados no influyó en el proceso. Se probaron tres cepas de T. gondii aisladas de las heces de un gato casero (TFC, de un Leopardus pardalis (TLP, de un Leopardus wiedii y de la carne de un Bos taurus (TBT. La cepa TLP resultó ser muy patógena, matando a los animales en un tiempo corto, independientemente de la inoculación con T. musculi; para las otras cepas se mantuvo el patrón de inmunosupresión en los ratones. Se reporta entonces un modelo experimental de inmunosupresión, aspecto muy en boga en este momento, por su relación con enfermedades que inducen esta condición en el ser humano, especialmente a enfermedades como el cáncer y el SIDA. Este modelo es más fácil de aplicar experimentalmente que el correspondiente con T. lewisi previamente descrito, el cual usa ratas blancas de más difícil manejo que los ratones usados en este estudio.The immunosuppression caused by species of the gender Trypanosoma has been widely documented. The influence over experimental infections with Toxoplasma gondii is evident when using Trypanosoma lewisi, a natural parasite of white rats. We decided to test the effect of Trypanosoma musculi from mice, an organism with very similar biological characteristics to T. lewisi, to see if this trypanosomatid could induce a similar

  20. Mode of Action of the Sesquiterpene Lactones Psilostachyin and Psilostachyin C on Trypanosoma cruzi.

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    Valeria P Sülsen

    Full Text Available Trypanosoma cruzi is the causative agent of Chagas' disease, which is a major endemic disease in Latin America and is recognized by the WHO as one of the 17 neglected tropical diseases in the world. Psilostachyin and psilostachyin C, two sesquiterpene lactones isolated from Ambrosia spp., have been demonstrated to have trypanocidal activity. Considering both the potential therapeutic targets present in the parasite, and the several mechanisms of action proposed for sesquiterpene lactones, the aim of this work was to characterize the mode of action of psilostachyin and psilostachyin C on Trypanosoma cruzi and to identify the possible targets for these molecules. Psilostachyin and psilostachyin C were isolated from Ambrosia tenuifolia and Ambrosia scabra, respectively. Interaction of sesquiterpene lactones with hemin, the induction of oxidative stress, the inhibition of cruzipain and trypanothione reductase and their ability to inhibit sterol biosynthesis were evaluated. The induction of cell death by apoptosis was also evaluated by analyzing phosphatidylserine exposure detected using annexin-V/propidium iodide, decreased mitochondrial membrane potential, assessed with Rhodamine 123 and nuclear DNA fragmentation evaluated by the TUNEL assay. Both STLs were capable of interacting with hemin. Psilostachyin increased about 5 times the generation of reactive oxygen species in Trypanosoma cruzi after a 4h treatment, unlike psilostachyin C which induced an increase in reactive oxygen species levels of only 1.5 times. Only psilostachyin C was able to inhibit the biosynthesis of ergosterol, causing an accumulation of squalene. Both sesquiterpene lactones induced parasite death by apoptosis. Upon evaluating the combination of both compounds, and additive trypanocidal effect was observed. Despite their structural similarity, both sesquiterpene lactones exerted their anti-T. cruzi activity through interaction with different targets. Psilostachyin

  1. Secondary Metabolites from Vietnamese Marine Invertebrates with Activity against Trypanosoma brucei and T. cruzi

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    Nguyen Phuong Thao

    2014-06-01

    Full Text Available Marine-derived natural products from invertebrates comprise an extremely diverse and promising source of the compounds from a wide variety of structural classes. This study describes the discovery of five marine natural products with activity against Trypanosoma species by natural product library screening using whole cell in vitro assays. We investigated the anti-trypanosomal activity of the extracts from the soft corals and echinoderms living in Vietnamese seas. Of the samples screened, the methanolic extracts of several marine organisms exhibited potent activities against cultures of Trypanosoma brucei and T. cruzi (EC50 < 5.0 μg/mL. Among the compounds isolated from these extracts, laevigatol B (1 from Lobophytum crassum and L. laevigatum, (24S-ergost-4-ene-3-one (2 from Sinularia dissecta, astropectenol A (3 from Astropecten polyacanthus, and cholest-8-ene-3β,5α,6β,7α-tetraol (4 from Diadema savignyi showed inhibitory activity against T. brucei with EC50 values ranging from 1.57 ± 0.14 to 14.6 ± 1.36 μM, relative to the positive control, pentamidine (EC50 = 0.015 ± 0.003 μM. Laevigatol B (1 and 5α-cholest-8(14-ene-3β,7α-diol (5 exhibited also significant inhibitory effects on T. cruzi. The cytotoxic activity of the pure compounds on mammalian cells was also assessed and found to be insignificant in all cases. This is the first report on the inhibitory effects of marine organisms collected in Vietnamese seas against Trypanosoma species responsible for neglected tropical diseases.

  2. Subcellular localization of glycolytic enzymes and characterization of intermediary metabolism of Trypanosoma rangeli.

    Science.gov (United States)

    Rondón-Mercado, Rocío; Acosta, Héctor; Cáceres, Ana J; Quiñones, Wilfredo; Concepción, Juan Luis

    2017-09-01

    Trypanosoma rangeli is a hemoflagellate protist that infects wild and domestic mammals as well as humans in Central and South America. Although this parasite is not pathogenic for human, it is being studied because it shares with Trypanosoma cruzi, the etiological agent of Chagas' disease, biological characteristics, geographic distribution, vectors and vertebrate hosts. Several metabolic studies have been performed with T. cruzi epimastigotes, however little is known about the metabolism of T. rangeli. In this work we present the subcellular distribution of the T. rangeli enzymes responsible for the conversion of glucose to pyruvate, as determined by epifluorescense immunomicroscopy and subcellular fractionation involving either selective membrane permeabilization with digitonin or differential and isopycnic centrifugation. We found that in T. rangeli epimastigotes the first six enzymes of the glycolytic pathway, involved in the conversion of glucose to 1,3-bisphosphoglycerate are located within glycosomes, while the last four steps occur in the cytosol. In contrast with T. cruzi, where three isoenzymes (one cytosolic and two glycosomal) of phosphoglycerate kinase are expressed simultaneously, only one enzyme with this activity is detected in T. rangeli epimastigotes, in the cytosol. Consistent with this latter result, we found enzymes involved in auxiliary pathways to glycolysis needed to maintain adenine nucleotide and redox balances within glycosomes such as phosphoenolpyruvate carboxykinase, malate dehydrogenase, fumarate reductase, pyruvate phosphate dikinase and glycerol-3-phosphate dehydrogenase. Glucokinase, galactokinase and the first enzyme of the pentose-phosphate pathway, glucose-6-phosphate dehydrogenase, were also located inside glycosomes. Furthermore, we demonstrate that T. rangeli epimastigotes growing in LIT medium only consume glucose and do not excrete ammonium; moreover, they are unable to survive in partially-depleted glucose medium. The

  3. Vector-borne transmission of Trypanosoma cruzi among captive Neotropical primates in a Brazilian zoo.

    Science.gov (United States)

    Minuzzi-Souza, Thaís Tâmara Castro; Nitz, Nadjar; Knox, Monique Britto; Reis, Filipe; Hagström, Luciana; Cuba, César A Cuba; Hecht, Mariana Machado; Gurgel-Gonçalves, Rodrigo

    2016-01-26

    Neotropical primates are important sylvatic hosts of Trypanosoma cruzi, the etiological agent of Chagas disease. Infection is often subclinical, but severe disease has been described in both free-ranging and captive primates. Panstrongylus megistus, a major T. cruzi vector, was found infesting a small-primate unit at Brasília zoo (ZooB), Brazil. ZooB lies close to a gallery-forest patch where T. cruzi circulates naturally. Here, we combine parasitological and molecular methods to investigate a focus of T. cruzi infection involving triatomine bugs and Neotropical primates at a zoo located in the Brazilian Savannah. We assessed T. cruzi infection in vectors using optical microscopy (n = 34) and nested PCR (n = 50). We used quantitative PCR (qPCR) to examine blood samples from 26 primates and necropsy samples from two primates that died during the study. We determined parasite lineages in five vectors and two primates by comparing glucose-6-phosphate isomerase (G6pi) gene sequences. Trypanosoma cruzi was found in 44 vectors and 17 primates (six genera and eight species); one Mico chrysoleucus and one Saguinus niger had high parasitaemias. Trypanosoma cruzi DNA was detected in three primates born to qPCR-negative mothers at ZooB and in the two dead specimens. One Callithrix geoffroyi became qPCR-positive over a two-year follow-up. All G6pi sequences matched T. cruzi lineage TcI. Our findings strongly suggest vector-borne T. cruzi transmission within a small-primate unit at ZooB - with vectors, and perhaps also parasites, presumably coming from nearby gallery forest. Periodic checks for vectors and parasites would help eliminate T. cruzi transmission foci in captive-animal facilities. This should be of special importance for captive-breeding programs involving endangered mammals, and would reduce the risk of accidental T. cruzi transmission to keepers and veterinarians.

  4. Acute inflammatory response to a foreign body in Calomys callosus Perfil de migração celular agudo induzido pela presença de corpo estranho em Calomys callosus

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    André Kipnis

    2008-07-01

    Full Text Available

    Calomys callosus are wild rodents present in the Brazilian savannas that were adapted to the laboratorial conditions. These animals are resistant to infections that induce chronic inflammatory responses (<em>Trypanosoma cruziem> and <em>Paracoccidioides brasiliensisem>. The objective of this work was to characterize the acute inflammatory reaction, prompted by the subcutaneous implementation of a foreign body. Twenty seven <em>C. callosusem> and thirty B10A mice received implant and were comparatively analyzed during 144 hours. Circular cover slides implanted in <em>C. callosusem> showed predominance of macrophages and eosinophils whereas in the mice, the neutrophils followed by the macrophages were the migratory dominant cells (p <0.05. It was concluded that <em>C. callosusem> present inflammatory mechanisms for the removal of foreign body different from the ones found in the other rodents as well as in the human beings.

     

    KEY WORDS: Acute inflammation, cover slip, granuloma, histology, wild rodents.

    Calomys callosus são roedores silvestres presentes no cerrado brasileiro, que foram adaptados às condições laboratoriais. Trata-se de animais que apresentam resistência às infecções que induzem respostas inflamatórias crônicas (<em>Trypanosoma cruziem> e <em>Paracoccidioides brasiliensisem>. O objetivo deste trabalho foi caracterizar a reação inflamatória, na fase aguda, induzida pela implantação subcutânea de um corpo estranho. Vinte e sete <em>C. callosusem> e trinta camundongos (B10A foram implantados e analisados comparativamente durante 144 horas. Lamínulas implantadas em <em>C. callosusem> mostraram predomínio de macrófagos e eosinófilos, enquanto que, nos camundongos, os neutrófilos seguidos pelos macrófagos foram as células migratórias dominantes (p< 0,05. Conclui-se que os <em>C. callosusem

  5. Acerca del ciclo evolutivo del Trypanosoma (Schizotrypanum cruzi Chagas 1909, en sus fases tisular y hematica

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    Cecilio Romaña

    1956-06-01

    Full Text Available El autor pasa en revista los trabajos publicados sobre el ciclo evolutivo del Trypanosoma (S. cruzi en el huésped vertebrado, desde el descubrimiento de la enfermedad hasta nuestros días. Luego analiza las ideas de los autores modernos, fundadas en gran parte en las observaciones que ya en 1914 realizaron MAYER y ROCHA LIMA de las cuales participan actualmente ROMAÑA y MEYER, ELKELES y WOOD. Finalmente expressa que a partir de los tripanosomas infectantes los parásitos que penetram en el protoplasma celular pueden seguir dos mecanismos en su evolución hacia cuerpos leishmanioides: 1.º Por "regresión fusiforme" y 2.º por "regresión orbicular"; llegados a la forma leishmanioide los parásitos se multiplican por división binaria, una vez lleno el protoplasma celular, siguen un processo inverso de transformación hacia tripanosoma que puede seguir igualmente dos mecanismos diversos: 1. "progresión fusiforme" y 2.º "progresión orbicular". Estos diversos mecanismos de transformación están esquematizados en la fig. N.º 1 del trabajo.The author reviews published works about the evolutive cycle of the Trypanosoma cruzi in the vertebrate host, from the discovery of the disease to our days. Then, he analyzes the ideas of the modern authors who based themselves on the observations made formerly, in 1914, by MAYER & ROCHA LIMA, ideas that ROMAÑA and MEYER, ELKELES and WOOD agree at the present time. Last, he states that, from the infective trypanosomas, the parasites which enter the cellular protoplasma may follow two systems to perform their evolution up to leishmanioid bodies: 1.] by fusiform regression, 2.º by an orbicular regression. Once the parasites reach the leishmanioid forms, they multiply by binary division. When the celular protoplasm is filled up with the parasites, these follow an inverted transformation up to trypanosoma state, following also two systems; similar to the repression 1.º a fusiform progression, 2.º an

  6. Heterogeneities in the Ecoepidemiology of Trypanosoma cruzi Infection in Rural Communities of the Argentinean Chaco

    OpenAIRE

    Cardinal, M. Victoria; Orozco, M. Marcela; Enriquez, Gustavo F.; Ceballos, Leonardo A.; Gaspe, María Sol; Alvarado-Otegui, Julián A.; Gurevitz, Juan M.; Kitron, Uriel; Gürtler, Ricardo E.

    2014-01-01

    We conducted a cross-sectional survey of Trypanosoma cruzi infection of Triatoma infestans as well as dogs and cats in 327 households from a well-defined rural area in northeastern Argentina to test whether the household distribution of infection differed between local ethnic groups (Tobas and Creoles) and identify risk factors for host infection. Overall prevalence of infection of bugs (27.2%; 95% confidence interval = 25.3–29.3%), dogs (26.0%; 95% confidence interval = 23.3–30.1%), and cats...

  7. Sialoglycoconjugates in Trypanosoma cruzi-host cell interaction: possible biological model - a review

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    Alane Beatriz Vermelho

    1994-03-01

    Full Text Available A number of glycoconjugates, including glycolipids and glycoproteins, participate in the process of host-cell invasion by Trypanosoma cruzi and one of the most important carbohydrates involved on this interaction is sialic acid. It is known that parasite trans-sialidase participates with sialic acid in a coordinated fashion in the initial stages of invasion. Given the importance of these sialogycoconjugates, this review sets out various possible biological models for the interaction between the parasite and mammalian cells that possess a sialylated receptor/ligand system.

  8. A haptoglobin-hemoglobin receptor conveys innate immunity to Trypanosoma brucei in humans

    DEFF Research Database (Denmark)

    Vanhollebeke, Benoit; De Muylder, Géraldine; Nielsen, Marianne J

    2008-01-01

    The protozoan parasite Trypanosoma brucei is lysed by apolipoprotein L-I, a component of human high-density lipoprotein (HDL) particles that are also characterized by the presence of haptoglobin-related protein. We report that this process is mediated by a parasite glycoprotein receptor, which...... binds the haptoglobin-hemoglobin complex with high affinity for the uptake and incorporation of heme into intracellular hemoproteins. In mice, this receptor was required for optimal parasite growth and the resistance of parasites to the oxidative burst by host macrophages. In humans, the trypanosome...... immunity against the parasite....

  9. Metabolic reprogramming during the Trypanosoma brucei life cycle [version 2; referees: 4 approved

    Directory of Open Access Journals (Sweden)

    Terry K. Smith

    2017-05-01

    Full Text Available Cellular metabolic activity is a highly complex, dynamic, regulated process that is influenced by numerous factors, including extracellular environmental signals, nutrient availability and the physiological and developmental status of the cell. The causative agent of sleeping sickness, Trypanosoma brucei, is an exclusively extracellular protozoan parasite that encounters very different extracellular environments during its life cycle within the mammalian host and tsetse fly insect vector. In order to meet these challenges, there are significant alterations in the major energetic and metabolic pathways of these highly adaptable parasites. This review highlights some of these metabolic changes in this early divergent eukaryotic model organism.

  10. Metabolic reprogramming during the Trypanosoma brucei life cycle [version 1; referees: 4 approved

    Directory of Open Access Journals (Sweden)

    Terry K. Smith

    2017-05-01

    Full Text Available Cellular metabolic activity is a highly complex, dynamic, regulated process that is influenced by numerous factors, including extracellular environmental signals, nutrient availability and the physiological and developmental status of the cell. The causative agent of sleeping sickness, Trypanosoma brucei, is an exclusively extracellular protozoan parasite that encounters very different extracellular environments during its life cycle within the mammalian host and tsetse fly insect vector. In order to meet these challenges, there are significant alterations in the major energetic and metabolic pathways of these highly adaptable parasites. This review highlights some of these metabolic changes in this early divergent eukaryotic model organism.

  11. Metabolic labeling with (14C)-glucose of bloodstream and cell culture trypanosoma cruzi trypomastigotes:

    International Nuclear Information System (INIS)

    Lederkremer, R.M. de; Groisman, J.F.; Lima, C.; Katzin, A.

    1990-01-01

    Trypomastigote forms of Trypanosoma cruzi from infected mouse blood and from cell culture were metabolically labeled by incubation with D-( 14 C)-glucose. Analysis by polyacrylamide gel electrophoresis of lysates from parasites of two strains (RA and CA 1 ) showed a significantly different pattern. The difference was mainly quantitative when the blood and cell culture trypomastigotes of the RA strain were compared. Analysis of the culture medium by paper electrophoresis showed an anionic exometabolite only in the blood forms of both strains. (Author) [es

  12. Studies on the virulence and attenuation of Trypanosoma cruzi using immunodeficient animals

    Directory of Open Access Journals (Sweden)

    Basombrío Miguel Ángel

    2000-01-01

    Full Text Available Tissue invasion and pathology by Trypanosoma cruzi result from an interaction between parasite virulence and host immunity. Successive in vivo generations of the parasite select populations with increasing ability to invade the host. Conversely, prolonged in vitro selection of the parasite produces attenuated sublines with low infectivity for mammals. One such subline (TCC clone has been extensively used in our laboratory as experimental vaccine and tested in comparative experiments with its virulent ancestor (TUL. The experiments here reviewed aimed at the use of immunodeficient mice for testing the infectivity of TCC parasites. It has not been possible to obtain virulent, revertant sublines by prolonged passaged in such mice.

  13. Marker discovery in Trypanosoma vivax through GSS and comparative analysis. Preliminary data and perspectives

    International Nuclear Information System (INIS)

    Davila, A.M.R.; Guerreiro, L.T.A.; Souza, S.S.

    2005-01-01

    Trypanosoma vivax is a haemoparasite affecting the livestock industry in South America and Africa. Despite the high economic relevance of the disease caused by T. vivax, little work has been done on its molecular characterization, in contrast with human trypanosomes, such as T. brucei and T. cruzi. The present study reports the construction of a semi-normalized genomic library and the sequencing of 160 Genome Sequence Survey (GSS) ends of T. vivax. The analyses of this preliminary data show that this simple and rapid approach worked well to generate some potential new markers for this species. (author)

  14. Drug discovery for Chagas disease should consider Trypanosoma cruzi strain diversity

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    Bianca Zingales

    2014-09-01

    Full Text Available This opinion piece presents an approach to standardisation of an important aspect of Chagas disease drug discovery and development: selecting Trypanosoma cruzi strains for in vitro screening. We discuss the rationale for strain selection representing T. cruzi diversity and provide recommendations on the preferred parasite stage for drug discovery, T. cruzi discrete typing units to include in the panel of strains and the number of strains/clones for primary screens and lead compounds. We also consider experimental approaches for in vitro drug assays. The Figure illustrates the current Chagas disease drug-discovery and development landscape.

  15. Inositol metabolism in Trypanosoma cruzi: potential target for chemotherapy against Chagas' disease

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    MECIA M. OLIVEIRA

    2000-09-01

    Full Text Available Chagas' disease is a debilitating and often fatal disease caused by the protozoan parasite Trypanosoma cruzi. The great majority of surface molecules in trypanosomes are either inositol-containing phospholipids or glycoproteins that are anchored into the plasma membrane by glycosylphosphatidylinositol anchors. The polyalcohol myo-inositol is the precursor for the biosynthesis of these molecules. In this brief review, recent findings on some aspects of the molecular and cellular fate of inositol in T. cruzi life cycle are discussed and identified some points that could be targets for the development of parasite-specific therapeutic agents.

  16. Histopathologic identification of Trypanosoma cruzi (Chagas' encephalitis in an AIDS patient

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    Dimath Alyemni

    2017-03-01

    Full Text Available Trypanosoma cruzi (Chagas' encephalitis is an uncommon manifestation of T. cruzi infection, typically seen in immunocompromised patients. Encephalitis results from the reactivation of chronic infection predominately in individuals from endemic areas. Increased awareness of this complication is essential especially with increased migration of patients from endemic areas with concomitant HIV infection. Here we report a case of Chagas' encephalitis in an AIDS patient from Mexico in which there was no evidence of acute serologic, CSF, or blood infection by T. cruzi trypomastigotes.

  17. Presence of Trypanosoma cruzi in tissues of experimentally infected Wistar rats and their fetuses

    OpenAIRE

    Alarcón, Maritza; Lugo de Yarbuh, Ana; Moreno, Elio A; Payares, Gilberto; Araujo, Sonia; Colmenares, Melisa

    2006-01-01

    Este estudio fue realizado con un grupo de ratas juveniles hembras (Rattus norvegicus) cepa Wistar con 20 días de nacidas y 250 grs. de peso. Cada rata fue inoculada inyectándole por vía intraperitoneal 0.1 mL de la suspensión sanguínea con 1x105 tripomastigotes sanguícolas de Trypanosoma cruzi (cepa I/PAS/VE/00/PLANALTO). Los parásitos fueron aislados de Panstrongylus geniculatus, naturalmente infectado y capturado en un área urbana del valle de Caracas, Venezuela y mantenidos en ratones NMR...

  18. Avances en el estudio de la Adenilato Quinasa Nuclear de Trypanosoma cruzi

    OpenAIRE

    Cámara, María de los Milagros

    2012-01-01

    Trypanosoma cruzi, el agente etiológico del Mal de Chagas es un eucariota inferior en donde el control de la expresión génica recae mayormente en mecanismos postraduccionales. Durante todo su ciclo de vida se observan fluctuaciones en la expresión génica. En la presente tesis se realizó el estudio de una adenilato quinasa nuclear (TcADKn) que se encuentra involucrada en la biogénesis ribosomal. Las adenilato quinasas nucleares han sido descriptas en muy pocos organismos, se las ha asociado al...

  19. Synthesis, Crystal Structure and Luminescent Property of Cd (II Complex with <em>N-Benzenesulphonyl-L>-leucine

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    Xishi Tai

    2012-09-01

    Full Text Available A new trinuclear Cd (II complex [Cd3(L6(2,2-bipyridine3] [L =<em> Nem>-phenylsulfonyl-L>-leucinato] has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction analysis. The results show that the complex belongs to the orthorhombic, space group<em> Pem>212121 with<em> aem> = 16.877(3 Å, <em>b> em>= 22.875(5 Å, <em>c em>= 29.495(6 Å, <em>α> em>= <emem>= <emem>= 90°, <em>V> em>= 11387(4 Å3, <em>Z> em>= 4, <em>Dc>= 1.416 μg·m−3, <emem>= 0.737 mm−1, <em>F> em>(000 = 4992, and final <em>R>1 = 0.0390, <em>ωR>2 = 0.0989. The complex comprises two seven-coordinated Cd (II atoms, with a N2O5 distorted pengonal bipyramidal coordination environment and a six-coordinated Cd (II atom, with a N2O4 distorted octahedral coordination environment. The molecules form one dimensional chain structure by the interaction of bridged carboxylato groups, hydrogen bonds and p-p interaction of 2,2-bipyridine. The luminescent properties of the Cd (II complex and <em>N-Benzenesulphonyl-L>-leucine in solid and in CH3OH solution also have been investigated.

  20. Rodent-borne Trypanosoma from cities and villages of Niger and Nigeria: A special role for the invasive genus Rattus?

    Science.gov (United States)

    Tatard, C; Garba, M; Gauthier, P; Hima, K; Artige, E; Dossou, D K H J; Gagaré, S; Genson, G; Truc, P; Dobigny, G

    2017-07-01

    Although they are known to sometimes infect humans, atypical trypanosomes are very poorly documented, especially in Africa where one lethal case has yet been described. Here we conducted a survey of rodent-borne Trypanosoma in 19 towns and villages of Niger and Nigeria, with a special emphasis on Niamey, the capital city of Niger. The 1298 rodents that were captured yielded 189 qPCR-positive animals from 14 localities, thus corresponding to a 14.6% overall prevalence. Rats, especially black rats, displayed particularly elevated prevalence (27.4%), with some well sampled sites showing 40-50% and up to 68.8% of Trypanosoma-carrying individuals. Rattus were also characterized by significantly lower Ct values than in the other non-Rattus species. DNA sequences could be obtained for 43 rodent-borne Trypanosoma and corresponded to 41 T. lewisi (all from Rattus) and 2 T. microti (from Cricetomys gambianus). These results, together with data compiled from the available literature, suggest that Rattus may play a particular role for the maintaining and circulation of Trypanosoma, especially T. lewisi, in Africa. Taken into account its strong abilities to invade coastal and inland regions of the continent, we believe that this genus deserves a particular attention in regards to potentially under-looked but emerging atypical trypanosome-related diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Structural model of a putrescine-cadaverine permease from Trypanosoma cruzi predicts residues vital for transport and ligand binding

    NARCIS (Netherlands)

    Soysa, R.; Venselaar, H.; Poston, J.; Ullman, B.; Hasne, M.P.

    2013-01-01

    The TcPOT1.1 gene from Trypanosoma cruzi encodes a high affinity putrescine-cadaverine transporter belonging to the APC (amino acid/polyamine/organocation) transporter superfamily. No experimental three-dimensional structure exists for any eukaryotic member of the APC family, and thus the structural

  2. THE CYTOSOLIC AND GLYCOSOMAL GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE FROM TRYPANOSOMA-BRUCEI - KINETIC-PROPERTIES AND COMPARISON WITH HOMOLOGOUS ENZYMES

    NARCIS (Netherlands)

    LAMBEIR, AM; LOISEAU, AM; KUNTZ, DA; VELLIEUX, FM; MICHELS, PAM; OPPERDOES, FR

    1991-01-01

    The protozoan haemoflagellate Trypanosoma brucei has two NAD-dependent glyceraldehyde-3-phosphate dehydrogenase isoenzymes, each with a different localization within the cell. One isoenzyme is found in the cytosol, as in other eukaryotes, while the other is found in the glycosome, a microbody-like

  3. Mitochondrial translation factors of Trypanosoma brucei: elongation factor-Tu has a unique subdomain that is essential for its function

    Czech Academy of Sciences Publication Activity Database

    Cristodero, M.; Mani, J.; Oeljeklaus, S.; Aeberhard, L.; Hashimi, Hassan; Ramrath, D.J.F.; Lukeš, Julius; Warscheid, B.; Schneider, A.

    2013-01-01

    Roč. 90, č. 4 (2013), s. 744-755 ISSN 0950-382X R&D Projects: GA ČR GAP305/12/2261 Institutional support: RVO:60077344 Keywords : mitochondrial translation * Trypanosoma brucei * EF-Tu Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.026, year: 2013

  4. Adaptations in the glucose metabolism of procyclic Trypanosoma brucei isolates from Tsetse flies and during differentiation of bloodstream forms.

    NARCIS (Netherlands)

    van Grinsven, K.W.A.; van den Abbeele, J.; van den Bossche, P.; van Hellemond, J.J.; Tielens, A.G.M.

    2009-01-01

    Procyclic forms of Trypanosoma brucei isolated from the midguts of infected tsetse flies, or freshly transformed from a strain that is close to field isolates, do not use a complete Krebs cycle. Furthermore, short stumpy bloodstream forms produce acetate and are apparently metabolically preadapted

  5. Phylogeny and morphological variability of trypanosomes from African pelomedusid turtles with redescription of Trypanosoma mocambicum Pienaar, 1962

    Czech Academy of Sciences Publication Activity Database

    Dvořáková, N.; Čepička, I.; Qablan, M. A.; Gibson, W.; Blažek, Radim; Široký, P.

    2015-01-01

    Roč. 166, č. 6 (2015), s. 599-608 ISSN 1434-4610 Institutional support: RVO:68081766 Keywords : Trypanosoma * turtle * Pelusios * polymorphism * phylogeny * SSU rRNA gene Subject RIV: EG - Zoology Impact factor: 2.898, year: 2015

  6. Utilização da fração semipurificada da proteinase do Trypanosoma cruzi no imunodiagnóstico da doença de Chagas The use of a semipurified fraction of Trypanosoma cruzi proteinase in immunodiagnosis of Chagas' disease

    Directory of Open Access Journals (Sweden)

    Ajax Mercês Atta

    1984-12-01

    Full Text Available Foram sensibilizadas hemácias humanas 0 Rh negativo com a fração semipurificada (Fp da proteinase do Trypanosoma cruzi, e testadas quanto a antigenicidade com soros de pacientes portadores de tripanossomíase americana crônica e de outras doenças parasitárias não relacionadas. Reações de hemaglutinação positivas foram observadas com os soros de pacientes chagásicos e com alguns soros de indivíduos portadores de leishmaniose cutaneo-mucosa. Não foram observadas reações cruzadas com os soros de pacientes portadores de leishmaniose visceral, malária, toxoplasmose, sífilis, esquistossomose e mononucleose. Os resultados obtidos são favoráveis ao emprego desta fração antigênica em testes de imunodiagnóstico da tripanossomíase americana.Group 0 Rh negative human erytrocytes were coated with the semipurified fraction of T. cruzi proteinase and tested with sera both from patients with chagas' disease and from others with unrelated parasitic diseases. Positive haemagglutination reactions were only observed with the sera from the former and with that from two patients with mucocutaneous leishmaniasis. No crossed reactions were observed with visceral leishmaniasis, malaria, toxoplasmosis syphilis, schistosomiasis or mononucleosis sera. Results suggest that this purified fraction can be used in immunodiagnosis of American Trypanosomiasis.

  7. Moderate physical exercise protects myenteric metabolically more active neurons in mice infected with Trypanosoma cruzi.

    Science.gov (United States)

    Moreira, Neide Martins; de Moraes, Solange Marta Franzói; Dalálio, M M O; Gomes, Mônica Lúcia; Sant'ana, D M G; de Araújo, Silvana Marques

    2014-02-01

    Trypanosoma cruzi causes neuronal myenteric depopulation compromising intestinal function. The purpose of this study was to evaluate the influence of moderate physical exercise on NADH diaphorase (NADH-d)-positive neurons in the myenteric plexus and intestinal wall of the colon in mice infected with T. cruzi. Forty 30-day-old male Swiss mice were divided into the following groups: trained infected (TI), sedentary infected (SI), trained control (TC), and sedentary control. The TC and TI groups were subjected to a moderate physical exercise program on a treadmill for 8 weeks. Three days after finishing physical exercise, the TI and SI groups were intraperitoneally inoculated with 1,300 blood trypomastigotes of the Y strain of Trypanosoma cruzi. Parasitemia was evaluated from days 4 to 61 after inoculation. On day 75 of infection, myenteric neurons in the colon were quantified (NADH-d), and inflammatory foci were counted. Tumor necrosis factor-α (TNF-α) and transforming growth factor-β (TGF-β) levels were evaluated in plasma. The results were compared using analysis of variance and the Kruskal-Wallis test at a 5 % significance level. Moderate physical exercise reduced the parasite peak on day 8 of infection (p = 0.0132) and total parasitemia (p = 0.0307). It also prevented neuronal depopulation (p  0.05). These results reinforce the therapeutic benefits of moderate physical exercise for T. cruzi infection.

  8. In vivo trypanocidal activity of Nymphaea lotus Linn. methanol extract against Trypanosoma brucei brucei

    Directory of Open Access Journals (Sweden)

    Muhammad Haruna Garba

    2015-10-01

    Full Text Available Objective: To evaluate the antitrypanosomal potentials of methanol extract of Nymphaea lotus Linn. (N. lotus with the aim of obtaining a new lead for formulating safe, inexpensive, nontoxic and readily available trypanocidal drugs. Methods: Seventy percent (v/v (methanol/water crude extract of N. lotus was evaluated for antitrypanosomal activity in experimental trypanosomiasis using Trypanosoma brucei bruceiinfected mice. Infected mice in different groups were administered intraperitoneally 100, 200, 300 and 400 mg/kg body weight/day of the crude for two weeks, while a positive control group was treated with standard drug, berenil. Results: The crude extract at a dose of 100 mg/kg body weight/day was more effective than the higher doses in completely clearing parasites from the blood of mice infected with Trypanosoma brucei brucei. Pre-treatment of healthy mice with the crude extract for 5 days before infection did not prevent the establishment of the infection, indicating that the extract had no prophylactic activity. Subinoculation of the blood and cerebrospinal fluid drawn from the cured mice into healthy mice failed to produce any infection within 50 days post inoculation. Administration of 1 000 mg/kg body weight of the crude extract led to the death of 50% of the experimental animals indicating a high level of toxicity of the extract at higher doses. Conclusions: This study has demonstrated the potency of the crude extract of N. lotus in treating experimental trypanosomiasis at lower doses.

  9. Seroprevalence of Trypanosoma cruzi in blood donors at the National Blood Transfusion Services--Guyana.

    Science.gov (United States)

    Bwititi, P T; Browne, J

    2012-09-01

    Blood transfusion is an important transmission route of Trypanosoma cruzi (T cruzi), a major parasitic infection in Central and South America. The limited treatment options are most effective in acute Chagas' infection. At present, there is no current data on the prevalence of T cruzi in the blood donor population of Guyana. This information is necessary to protect the supply of the blood donation programme. This study sought to determine the prevalence of T cruzi in the blood supply at the National Blood Transfusion Services of Guyana with the hope of providing knowledge to the on-going surveillance for Chagas' disease worldwide and therefore address the risk of its spread by blood transfusion. Two commercialized ELISAs utilizing crude or recombinant T cruzi antigens were used to study 2000 blood samples voluntarily donated for the purpose of altruistic or family replacement donation retrospectively. The results showed that approximately 1 in 286 donations tested positive for antibodies to T cruzi. These results indicate that T cruzi continues to be a risk in Guyana and there is a need to continue screening donated blood. Trypanosoma cruzi is a life-long infection and infected persons may be asymptomatic chronic carriers of the disease. Education, housing improvement, and controlled use of insecticides should be introduced to contain Chagas' disease.

  10. Investigating the Chaperone Properties of a Novel Heat Shock Protein, Hsp70.c, from Trypanosoma brucei

    Directory of Open Access Journals (Sweden)

    Adélle Burger

    2014-01-01

    Full Text Available The neglected tropical disease, African Trypanosomiasis, is fatal and has a crippling impact on economic development. Heat shock protein 70 (Hsp70 is an important molecular chaperone that is expressed in response to stress and Hsp40 acts as its co-chaperone. These proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. A novel cytosolic Hsp70, from Trypanosoma brucei, TbHsp70.c, contains an acidic substrate binding domain and lacks the C-terminal EEVD motif. The ability of a cytosolic Hsp40 from Trypanosoma brucei J protein 2, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated. The main objective was to functionally characterize TbHsp70.c to further expand our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed the ability to suppress aggregation of thermolabile MDH and chemically denatured rhodanese. ATPase assays revealed a 2.8-fold stimulation of the ATPase activity of TbHsp70.c by Tbj2. TbHsp70.c and Tbj2 both demonstrated chaperone activity and Tbj2 functions as a co-chaperone of TbHsp70.c. In vivo heat stress experiments indicated upregulation of the expression levels of TbHsp70.c.

  11. Trans-sialidase inhibition assay detects Trypanosoma cruzi infection in different wild mammal species.

    Science.gov (United States)

    Sartor, Paula A; Ceballos, Leonardo A; Orozco, Marcela M; Cardinal, Marta V; Gürtler, Ricardo E; Leguizamón, María S

    2013-08-01

    The detection of Trypanosoma cruzi infection in mammals is crucial for understanding the eco-epidemiological role of the different species involved in parasite transmission cycles. Xenodiagnosis (XD) and hemoculture (HC) are routinely used to detect T. cruzi in wild mammals. Serological methods are much more limited because they require the use of specific antibodies to immunoglobulins of each mammalian species susceptible to T. cruzi. In this study we detected T. cruzi infection by trans-sialidase (TS) inhibition assay (TIA). TIA is based on the antibody neutralization of a recombinant TS that avoids the use of anti-immunoglobulins. TS activity is not detected in the co-endemic protozoan parasites Leishmania spp and T. rangeli. In the current study, serum samples from 158 individuals of nine wild mammalian species, previously tested by XD, were evaluated by TIA. They were collected from two endemic areas in northern Argentina. The overall TIA versus XD co-reactivity was 98.7% (156/158). All 18 samples from XD-positive mammals were TIA-positive (co-positivity, 100%) and co-negativity was 98.5% (138/140). Two XD-negative samples from a marsupial (Didelphis albiventris) and an edentate (Dasypus novemcinctus) were detected by TIA. TIA could be used as a novel tool for serological detection of Trypanosoma cruzi in a wide variety of sylvatic reservoir hosts.

  12. The flagellum of Trypanosoma brucei: new tricks from an old dog

    Science.gov (United States)

    Ralston, Katherine S.; Hill, Kent L.

    2010-01-01

    African trypanosomes, i.e. Trypanosoma brucei and related sub-species, are devastating human and animal pathogens that cause significant human mortality and limit sustained economic development in sub-Saharan Africa. Trypanosoma brucei is a highly motile protozoan parasite and coordinated motility is central to both disease pathogenesis in the mammalian host and parasite development in the tsetse fly vector. Since motility is critical for parasite development and pathogenesis, understanding unique aspects of the T. brucei flagellum may uncover novel targets for therapeutic intervention in African sleeping sickness. Moreover, studies of conserved features of the T. brucei flagellum are directly relevant to understanding fundamental aspects of flagellum and cilium function in other eukaryotes, making T. brucei an important model system. The T. brucei flagellum contains a canonical 9 + 2 axoneme, together with additional features that are unique to kinetoplastids and a few closely-related organisms. Until recently, much of our knowledge of the structure and function of the trypanosome flagellum was based on analogy and inference from other organisms. There has been an explosion in functional studies in T. brucei in recent years, revealing conserved as well as novel and unexpected structural and functional features of the flagellum. Most notably, the flagellum has been found to be an essential organelle, with critical roles in parasite motility, morphogenesis, cell division and immune evasion. This review highlights recent discoveries on the T. brucei flagellum. PMID:18472102

  13. Trypanosoma cf. varani in an imported ball python (Python reginus) from Ghana.

    Science.gov (United States)

    Sato, Hiroshi; Takano, Ai; Kawabata, Hiroki; Une, Yumi; Watanabe, Haruo; Mukhtar, Maowia M

    2009-08-01

    Peripheral blood from a ball python (Python reginus) imported from Ghana was cultured in Barbour-Stoenner-Kelly (BSK) medium for Borrelia spp. isolation, resulting in the prominent appearance of free, and clusters of, trypanosomes in a variety of morphological forms. The molecular phylogenetic characterization of these cultured trypanosomes, using the small subunit rDNA, indicated that this python was infected with a species closely related to Trypanosoma varani Wenyon, 1908, originally described in the Nile monitor lizard (Varanus niloticus) from Sudan. Furthermore, nucleotide sequences of glycosomal glyceraldehyde-3-phosphate dehydrogenase gene of both isolates showed few differences. Giemsa-stained blood smears, prepared from the infected python 8 mo after the initial observation of trypanosomes in hemoculture, contained trypomastigotes with a broad body and a short, free flagellum; these most closely resembled the original description of T. varani, or T. voltariae Macfie, 1919 recorded in a black-necked spitting cobra (Naja nigricollis) from Ghana. It is highly possible that lizards and snakes could naturally share an identical trypanosome species. Alternatively, lizards and snakes in the same region might have closely related, but distinct, Trypanosoma species as a result of sympatric speciation. From multiple viewpoints, including molecular phylogenetic analyses, reappraisal of trypanosome species from a wide range of reptiles in Africa is needed to clarify the relationship of recorded species, or to unmask unrecorded species.

  14. Molecular epidemiology of Trypanosoma cruzi and Triatoma dimidiata in costal Ecuador.

    Science.gov (United States)

    Wong, Yim Yan; Sornosa Macias, Karen Jeniffer; Guale Martínez, Doris; Solorzano, Luis F; Ramirez-Sierra, Maria Jesus; Herrera, Claudia; Dumonteil, Eric

    2016-07-01

    Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. In Ecuador, Triatoma dimidiata and Rhodnius ecuadoriensis are the main vector species, responsible for over half of the cases of T. cruzi infection in the country. T. dimidiata is believed to have been introduced in Ecuador during colonial times, and its elimination from the country is thus believed to be feasible. We investigated here the molecular ecology of T. dimidiata and T. cruzi in costal Ecuador to further guide control efforts. Analysis of the Internal Transcribed Spacer 2 (ITS-2) of 23 specimens from Progreso, Guayas, unambiguously supported the likely importation of T. dimidiata from Central America to Ecuador. The observation of a very high parasite infection rate (54%) and frequent feeding on humans (3/5) confirmed a continued risk of transmission to humans. All genotyped parasites corresponded to TcI DTU and Trypanosoma rangeli was not detected in T. dimidiata. TcI subgroups corresponded to TcIa (25%), and mixed infections with TcIa and TcId (75%). Further studies should help clarify T. cruzi genetic structure in the country, and the possible impact of the introduction of T. dimidiata on the circulating parasite strains. The elevated risk posed by this species warrants continuing efforts for its control, but its apparent mobility between peridomestic and domestic habitats may favor reinfestation following insecticide spraying. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Plants of Brazilian restingas with tripanocide activity against Trypanosoma cruzi strains.

    Science.gov (United States)

    Faria, Robson Xavier; Souza, André Luis Almeida; Lima, Barbara; Tietbohl, Luis Armando Candido; Fernandes, Caio Pinho; Amaral, Raquel Rodrigues; Ruppelt, Bettina Monika; Santos, Marcelo Guerra; Rocha, Leandro

    2017-12-01

    Chagas disease is caused by the Trypanosoma cruzi affecting millions of people, and widespread throughout Latin America. This disease exhibits a problematic chemotherapy. Benznidazole, which is the drug currently used as standard treatment, lamentably evokes several adverse reactions. Among other options, natural products have been tested to discover a novel therapeutic drug for this disease. A lot of plants from the Brazilian flora did not contain studies about their biological effects. Restinga de Jurubatiba from Brazil is a sandbank ecosystem poorly studied in relation to plant biological activity. Thus, three plant species from Restinga de Jurubatiba were tested against in vitro antiprotozoal activity. Among six extracts obtained from leaves and stem parts and 2 essential oils derived from leave parts, only 3 extracts inhibited epimastigote proliferation. Substances present in the extracts with activity were isolated (quercetin, myricetin, and ursolic acid), and evaluated in relation to antiprotozoal activity against epimastigote Y and Dm28 Trypanosoma cruzi strains. All isolated substances were effective to reduce protozoal proliferation. Essentially, quercetin and myricetin did not cause mammalian cell toxicity. In summary, myricetin and quercetin molecule can be used as a scaffold to develop new effective drugs against Chagas's disease.

  16. Prevalence of antibodies to Trypanosoma cruzi, Toxoplasma gondii, Encephalitozonn cuniculi, Sarcocystis neurona, Besnoitia darlingi, and Neospora caninum in North American opossum, Didelphis virginiana, from Southern Louisian

    Science.gov (United States)

    We examined the prevalence of antibodies to zoonotic protozoan parasites (Trypanosoma cruzi, Toxoplasma gondii, and Encephalitozoon cuniculi) and protozoan’s of veterinary importance (Neospora caninum, Sarcocystis neurona and Besnoitia darlingi) in a population of North American opossums (Didelphis...

  17. Trypanosoma teixeirae: A new species belonging to the T. cruzi clade causing trypanosomosis in an Australian little red flying fox (Pteropus scapulatus).

    Science.gov (United States)

    Barbosa, Amanda D; Mackie, John T; Stenner, Robyn; Gillett, Amber; Irwin, Peter; Ryan, Una

    2016-06-15

    Little is known about the genetic diversity and pathogenicity of trypanosomes in Australian bats. Recently a novel trypanosome species was identified in an adult female little red flying fox (Pteropus scapulatus) with clinical and pathological evidence of trypanosomosis. The present study used morphology and molecular methods to demonstrate that this trypanosome is a distinct species and we propose the name Trypanosoma teixeirae sp. n. Morphological comparison showed that its circulating trypomastigotes were significantly different from those of Trypanosoma pteropi and Trypanosoma hipposideri, two species previously described from Australian bats. Genetic information was not available for T. pteropi and T. hipposideri but phylogenetic analyses at the 18S ribosomal RNA (rRNA) and glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) loci indicated that T. teixeirae sp. n. was genetically distinct and clustered with other bat-derived trypanosome species within the Trypanosoma cruzi clade. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. [Early stages of development of Trypanosoma rotatorium (Mayer, 1843) from peripheral blood and internal organs of Anurans Bufo bufo (Linnaeus) and Rana sp. (Anura)].

    Science.gov (United States)

    Malysheva, M N

    2014-01-01

    The data on the fauna of trypanosomes of Anura of the Leningrad Province are given. The initial development stages of Trypanosoma rotatorium in peripheral blood and internal organs of the frog are described for the first time.

  19. Characterization of a Novel Class I Transcription Factor A (CITFA) Subunit That Is Indispensable for Transcription by the Multifunctional RNA Polymerase I of Trypanosoma brucei

    KAUST Repository

    Nguyen, T. N.; Nguyen, B. N.; Lee, J. H.; Panigrahi, A. K.; Gunzl, A.

    2012-01-01

    Trypanosoma brucei is the only organism known to have evolved a multifunctional RNA polymerase I (pol I) system that is used to express the parasite's ribosomal RNAs, as well as its major cell surface antigens, namely, the variant surface

  20. Effect of experimental single Ancylostoma caninum and mixed infections of Trypanosoma brucei and Trypanosoma congolense on the humoural immune response to anti-rabies vaccination in dogs

    Directory of Open Access Journals (Sweden)

    Nwoha Rosemary Ijeoma Ogechi

    2015-06-01

    Full Text Available Objective: To determine the effect of Ancylostoma caninum (A. caninum and trypanosome parasites on the immune response to vaccination in dogs in endemic environments. Methods: Sixteen dogs for the experiment were grouped into 4 of 4 members each. Group I was the uninfected control one, and GPII was infected with A. caninum; GPIII was infected with A. caninum/Trypanosoma congolense (T. congolense, and GPIV was infected with Trypanosoma brucei (T. brucei/A. caninum. The dogs were first vaccinated with antirabies vaccine before infecting GPII, GPIII and GPIV with A. caninum which were done 4 weeks after vaccination. By 2-week post-vaccination, trypanosome parasites were superimposed on both GPIII and GPIV. A secondary vaccination was given to GPI, GPII, GPIII, and GPIV by Week 12 of the experiment (4 weeks post treatment. Results: The prepatent period was (3.00 ± 1.40 days, in the conjunct infection of T. brucei/ A. caninum. It was (9.00 ± 1.10 days, in conjunct T. congolense/A. caninum. The prepatent period of A. caninum was (14.0 ± 2.0 days in the single A. caninum group and (13.0 ± 1.0 days in the conjunct trypanosome/A. caninum. At the 1st week after vaccination, the antibody titer in all the vaccinated groups (GPI, GPII, GPIII, and GPIV significantly increased (P < 0.05 and peaked at the 3rd week after vaccination. Following infections, there were marked significant decreases (P < 0.05 in the antibody production against rabies in GPII, GPIII and GPIV. The significant decrease (P < 0.05 in antibody titer was highest in the conjunct groups (GPIII and GPIV compared to the single infection (GPII. Treatment with diminazene aceturate and mebendazole did not significantly improve antibody response in the dogs. A secondary vaccination administered at the 12th week after the primary vaccination significantly increased (P < 0.05 the antibody titer with a peak at the 3rd week after the secondary vaccination. Conclusions: It was therefore concluded

  1. Estudios sobre Trypanosoma rangeli Tejera, 1920: VIII. Respuesta a las reinfecciones en dos mamíferos Trypanosoma rangeli Tejera, 1920: VIII. Responses to reinfections in 2 mammals

    Directory of Open Access Journals (Sweden)

    N. Añez

    1985-06-01

    Full Text Available Bajo condiciones experimentales se estudia el curso de la infección primaria y la respuesta a las reinfecciones por Trypanosoma rangeli en ratones albinos y Didelphis marsupialis. Durante el curso de la infección primaria en ratones, se observa una parasitemia relativamente baja y de corta duración. Los mismos muestran durante la primera reinfección una parasitemia escasa de cuatro días de duración, siendo resistentes a las sucesivas reinfecciones con T. rangeli. Los ejemplares de D. marsupialis exhiben una parasitemia de más larga duración, pero con un nivel de parásitos sanguícolas mucho menor que el detectado en el modelo ratón, siendo la respuesta a las reinfecciones similar a la observada en ratones. Se detectan anticuerpos hemaglutinantes en los sueros inmunes de ratones y Didelphis marsupialis, sometidos a la reinfección por T. rangeli. Se especula sobre la posible acción sinérgica de una respuesta inmune en el sitio de deposición en contra de las formas metacíclicas de T. rangeli y la acción de anticuerpos circulantes en contra de las formas sanguícolas, para explicar la resistencia de ambos modelos a las reinfecciones por T. rangeli.Under experimental conditions, the course of the infection and the response to the reinfection by Trypanosoma rangeli in mice and Didelphis marsupialis, are studied. During the initial infection the mice show a relatively low parasitaemia and a short patent period. A scanty parasitaemia level of four days length, was observed following the first reinfection, being the mice resistant to new reinfections by T. rangeli. In opossums a lower parasitaemia and a longer patent period than that detected in mice, were observed during the initial infection. The response to reinfections in this mammal, was similar to that observed in mice. After reinfection with T. rangeli, haemagglutinant antibodies in immune-sera of both mice and opossums, were detected. The possible immune-response at the site of

  2. Infections of Hypostomus spp. by Trypanosoma spp. and leeches: a study of hematology and record of these hirudineans as potential vectors of these hemoflagellates

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    Lincoln Lima Corrêa

    Full Text Available Abstract Among Kinetoplastida, the Trypanosoma is the genus with the highest occurrence infecting populations of marine fish and freshwater in the world, with high levels of prevalence, causing influences fish health and consequent economic losses, mainly for fish populations in situation stress. This study investigated infections of Hypostomus spp. by Trypanosoma spp. and leeches, as well as blood parameters of this host in the network of tributaries of the Tapajós River in the state of Pará, in the eastern Amazon region in Brazil. Of the 47 hosts examined, 89.4% were parasitized by Trypanosoma spp. and 55.4% also had leeches attached around the mouth. The intensity of Trypanosoma spp. increased with the size of the host, but the body conditions were not influenced by the parasitism. The number of red blood cells, and hemoglobin, mean corpuscular volume (MCV, mean corpuscular hemoglobin concentration (MCHC, mean corpuscular hemoglobin (MCH, total number of leukocytes and thrombocytes showed variations and negative correlation with the intensity of Trypanosoma spp. in the blood of the hosts. The results suggest that the leeches were vectors of Trypanosoma spp. in Hypostomus spp.

  3. Neonatal Phosphate Nutrition Alters <em>in em>Vivo> and <em>in em>Vitro> Satellite Cell Activity in Pigs

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    Chad H. Stahl

    2012-05-01

    Full Text Available Satellite cell activity is necessary for postnatal skeletal muscle growth. Severe phosphate (PO4 deficiency can alter satellite cell activity, however the role of neonatal PO4 nutrition on satellite cell biology remains obscure. Twenty-one piglets (1 day of age, 1.8 ± 0.2 kg BW were pair-fed liquid diets that were either PO4 adequate (0.9% total P, supra-adequate (1.2% total P in PO4 requirement or deficient (0.7% total P in PO4 content for 12 days. Body weight was recorded daily and blood samples collected every 6 days. At day 12, pigs were orally dosed with BrdU and 12 h later, satellite cells were isolated. Satellite cells were also cultured <em>in vitroem> for 7 days to determine if PO4 nutrition alters their ability to proceed through their myogenic lineage. Dietary PO4 deficiency resulted in reduced (<em>P> < 0.05 sera PO4 and parathyroid hormone (PTH concentrations, while supra-adequate dietary PO4 improved (<em>P> < 0.05 feed conversion efficiency as compared to the PO4 adequate group. <em>In vivoem> satellite cell proliferation was reduced (<em>P> < 0.05 among the PO4 deficient pigs, and these cells had altered <em>in vitroem> expression of markers of myogenic progression. Further work to better understand early nutritional programming of satellite cells and the potential benefits of emphasizing early PO4 nutrition for future lean growth potential is warranted.

  4. Unraveling the differences of the hydrolytic activity of Trypanosoma cruzi trans-sialidase and Trypanosoma rangeli sialidase: a quantum mechanics-molecular mechanics modeling study.

    Science.gov (United States)

    Bueren-Calabuig, Juan A; Pierdominici-Sottile, Gustavo; Roitberg, Adrian E

    2014-06-05

    Chagas' disease, also known as American trypanosomiasis, is a lethal, chronic disease that currently affects more than 10 million people in Central and South America. The trans-sialidase from Trypanosoma cruzi (T. cruzi, TcTS) is a crucial enzyme for the survival of this parasite: sialic acids from the host are transferred to the cell surface glycoproteins of the trypanosome, thereby evading the host's immune system. On the other hand, the sialidase of T. rangeli (TrSA), which shares 70% sequence identity with TcTS, is a strict hydrolase and shows no trans-sialidase activity. Therefore, TcTS and TrSA represent an excellent framework to understand how different catalytic activities can be achieved with extremely similar structures. By means of combined quantum mechanics-molecular mechanics (QM/MM, SCC-DFTB/Amberff99SB) calculations and umbrella sampling simulations, we investigated the hydrolysis mechanisms of TcTS and TrSA and computed the free energy profiles of these reactions. The results, together with our previous computational investigations, are able to explain the catalytic mechanism of sialidases and describe how subtle differences in the active site make TrSA a strict hydrolase and TcTS a more efficient trans-sialidase.

  5. Constituents from <em>Vigna em>vexillata> and Their Anti-Inflammatory Activity

    Directory of Open Access Journals (Sweden)

    Guo-Feng Chen

    2012-08-01

    Full Text Available The seeds of <em>Vigna em>genus are important food resources and there have already been many reports regarding their bioactivities. In our preliminary bioassay, the chloroform layer of methanol extracts of<em> V. vexillata em>demonstrated significant anti-inflammatory bioactivity. Therefore, the present research is aimed to purify and identify the anti-inflammatory principles of <em>V. vexillataem>. One new sterol (1 and two new isoflavones (2,3 were reported from the natural sources for the first time and their chemical structures were determined by the spectroscopic and mass spectrometric analyses. In addition, 37 known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature. Among the isolates, daidzein (23, abscisic acid (25, and quercetin (40 displayed the most significant inhibition of superoxide anion generation and elastase release.

  6. Fertility of the Small East African goat following pre-pubertal infection with Trypanosoma congolense

    International Nuclear Information System (INIS)

    O'Hara, H.B.; Gombe, S.

    1991-01-01

    Pre-pubertal male and female Small East African goats were infected with Trypanosoma congolense at 4-5 months of age. Changes in body weight and haemogram were monitored weekly. Progesterone and testosterone measurements were made three times weekly until the goats either reached puberty or 18 months of age. Onset of puberty was determined from observation of oestrus behaviour, mating or increase in libidio; this was confirmed by elevation in plasma progesterone or testosterone levels. Trypanosomiasis affected pre-pubertal goats by reducing body weight gain and delaying onset of puberty. Histological examination of the gonads showed pronounced pathological changes. These effects were reversed by treatment with isometamidium chloride (Samorin, May and Baker). It was concluded that early treatment of infected goats before serious gonadal damage could occur allowed full restoration of reproductive function. (author). 6 refs, 4 figs, 1 tab

  7. A new bianthron glycoside as inhibitor of Trypanosoma cruzi glyceraldehyde 3-phosphate dehydrogenase activity

    International Nuclear Information System (INIS)

    Macedo, Edangelo M.S. de; Silva, Maria G.V.; Wiggers, Helton J.; Montanari, Carlos A.; Braz-Filho, Raimundo; Andricopulo, Adriano D.

    2009-01-01

    A phytochemical investigation of the ethanolic extract of stalks of Senna martiana Benth. (Leguminoseae), native specie of northeast Brazil, resulted in the isolation and spectroscopic characterization of a new bianthrone glycoside, martianine 1 (10,10'-il-chrysophanol-10-oxi- 10,10'-bi-glucosyl). Its identification was established by HRMS, IR and 2D NMR experiments. The evaluation of martianine trypanocidal activity was carried out against gliceraldehyde 3-phosphate dehydrogenase enzyme from Trypanosoma cruzi. Its inhibitory constant (K i ) is in the low micromolar concentration and it was determined by isothermal titration calorimetry to be 27.3 +-2.47 μmol L -1 . The non-competitive mechanism is asserted to be putative of the mode of action martianine displays against T. cruzi GAPDH. Results show that martianine has a great potential to become new lead molecule by inhibiting this key enzyme and for the development of new drugs against Chagas disease. (author)

  8. Selection and optimization of hits from a high-throughput phenotypic screen against Trypanosoma cruzi.

    Science.gov (United States)

    Keenan, Martine; Alexander, Paul W; Chaplin, Jason H; Abbott, Michael J; Diao, Hugo; Wang, Zhisen; Best, Wayne M; Perez, Catherine J; Cornwall, Scott M J; Keatley, Sarah K; Thompson, R C Andrew; Charman, Susan A; White, Karen L; Ryan, Eileen; Chen, Gong; Ioset, Jean-Robert; von Geldern, Thomas W; Chatelain, Eric

    2013-10-01

    Inhibitors of Trypanosoma cruzi with novel mechanisms of action are urgently required to diversify the current clinical and preclinical pipelines. Increasing the number and diversity of hits available for assessment at the beginning of the discovery process will help to achieve this aim. We report the evaluation of multiple hits generated from a high-throughput screen to identify inhibitors of T. cruzi and from these studies the discovery of two novel series currently in lead optimization. Lead compounds from these series potently and selectively inhibit growth of T. cruzi in vitro and the most advanced compound is orally active in a subchronic mouse model of T. cruzi infection. High-throughput screening of novel compound collections has an important role to play in diversifying the trypanosomatid drug discovery portfolio. A new T. cruzi inhibitor series with good drug-like properties and promising in vivo efficacy has been identified through this process.

  9. A Highly Sensitive Rapid Diagnostic Test for Chagas Disease That Utilizes a Recombinant Trypanosoma cruzi Antigen

    Science.gov (United States)

    Barfield, C. A.; Barney, R. S.; Crudder, C. H.; Wilmoth, J. L.; Stevens, D. S.; Mora-Garcia, S.; Yanovsky, M. J.; Weigl, B. H.; Yanovsky, J.

    2011-01-01

    Improved diagnostic tests for Chagas disease are urgently needed. A new lateral flow rapid test for Chagas disease is under development at PATH, in collaboration with Laboratorio Lemos of Argentina, which utilizes a recombinant antigen for detection of antibodies to Trypanosoma cruzi. To evaluate the performance of this test, 375 earlier characterized serum specimens from a region where Chagas is endemic were tested using a reference test (the Ortho T. cruzi ELISA, Johnson & Johnson), a commercially available rapid test (Chagas STAT-PAK, Chembio), and the PATH–Lemos rapid test. Compared to the composite reference tests, the PATH–Lemos rapid test demonstrated an optimal sensitivity of 99.5% and specificity of 96.8%, while the Chagas STAT-PAK demonstrated a sensitivity of 95.3% and specificity of 99.5%. These results indicate that the PATH–Lemos rapid test shows promise as an improved and reliable tool for screening and diagnosis of Chagas disease. PMID:21342808

  10. Activity of D-carnitine and its derivatives on Trypanosoma infections in rats and mice

    Directory of Open Access Journals (Sweden)

    Manganaro M.

    2003-06-01

    Full Text Available Little progress has been made in the treatment of African trypanosomiasis over the past decades. L-carnitine has a major role in glycolysis-based energy supply of blood trypanosomes for it stimulates constant ATP production. To investigate whether administration of the isomer D-carnitine could exert a competitive inhibition on the metabolic pathway of the L-form, possibily resulting in parasite replication inhibition, several formulations of this compound were tested on Trypanosoma lewisi and T. brucei rhodesiense in rodent models. High oral dosages of D-carnitine inner salt and proprionyl-D-carnitine were not toxic to animals and induced about 50 % parasite growth inhibition in reversible, i.e. competitive, fashion. A putative mechanism could be an interference in pyruvate kinase activity and hence ATP production. Considering both, lack of toxicity and inhibitory activity, D-carnitine may have a role in the treatment of African trypanosomiasis, in association with available trypanocidal drugs.

  11. Genetic characterization of Trypanosoma cruzi natural clones from the state of Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    Christian Barnabé

    2005-05-01

    Full Text Available Eighteen Trypanosoma cruzi stocks from the state of Paraíba, Brazil, isolated from man, wild mammals, and triatomine bugs were studied by multilocus enzyme electrophoresis and random primed amplified polymorphic DNA. Despite the low number of stocks, a notable genetic, genotypic, and phylogenetic diversity was recorded. The presence of the two main phylogenetic subdivisions, T. cruzi I and II, was recorded. The strong linkage disequilibrium observed in the population under survey suggests that T. cruzi undergoes predominant clonal evolution in this area too, although this result should be confirmed by a broader sample. The pattern of clonal variation does not suggests a recent origin by founder effect with a limited number of different genotypes.

  12. Prevalencia de infeccion a Trypanosoma cruzi en donadores de sangre en el Estado de Jalisco, Mexico

    Directory of Open Access Journals (Sweden)

    Francisco Trujillo Contreras

    1993-06-01

    Full Text Available Durante el periodo de Octubre de 1991 a Marzo de 1992, se tomaron 3419 muestras de donadores de sangre de 12 localidades rurales y de 8 hospitales urbanos a los que se les realizo un estúdio serológico mediante la reacción de hemaglutinación indirecta encontrándose anticuerpos contra Trypanosoma cruzi en 44 indivíduos 39 masculinosy 5 femininos. El 90,9% de donantes fueron masculinos. De acuerdo a su procedencia, el 73,5% fué del área urbana y el 26,5% del área rural. De acuerdo a los resultados el riesgo de transmisión de T. cruzi por transfusión sanguinea está latente por la creciente urbanización de la enfermedad de Chagas.

  13. Genómica del Trypanosoma cruzi. Nuevas oportunidades para tratar el mal de Chagas

    Directory of Open Access Journals (Sweden)

    Jorge A. Huete-Pérez

    2006-12-01

    Full Text Available LA SECUENCIACIÓN DEL GENOMA HUMANO PUBLICADA EN FEBRERO de 2001 ha sido considerada como el hito científico más importante del siglo XX. La secuenciación, cuatro años más tarde, de tres parásitos tripanosmatidas, entre ellos el Trypanosoma cruzi, podría ser también catalogada como uno de los acontecimientos científicos más importantes para la salud publica del continente americano. Aquí se presenta un panorama general sobre los resultados más significativos del estudio geonómico del T. cruzi, se abordan los trabajos realizados por nuestro laboratorio en la Universidad Centroamericana, finalizando con una discusión sobre las perspectivas del uso de la genómica en Nicaragua.

  14. Effects of water deprivation on renal hydroelectrolytic excretion in chronically Trypanosoma cruzi-infected rats

    Directory of Open Access Journals (Sweden)

    T.T. Rosa

    1995-03-01

    Full Text Available The effect of an 8 hour-period of water deprivation on fluid and electrolyte renal excretion was investigated in male Wistar rats infected with the strain São Felipe (12SF of Trypanosoma cruzi, in comparison with age and sex matched non-infected controls. The median percent reductions in the urinary flow (-40% v -63% and excretion ofsodium (-57% v-79% were smaller in chagasic than in control rats, respectively. So, chagasic rats excreted more than controls. On the other hand, the median percent decrement in the clearance of creatinine was higher in chagasic (-51% than in controls (-39%. Thus, chagasic rats showed some disturbed renal hydroelectrolytic responses to water deprivation, expressed by smaller conservation, or higher excretion of water and sodium in association with smaller glomerularfiltration rate. This fact denoted an elevation in the fractional excretion of sodium and water.

  15. [Seroprevalence of Trypanosoma cruzi infection in the rural population of Sucre State, Venezuela].

    Science.gov (United States)

    García-Jordán, Noris; Berrizbeitia, Mariolga; Rodríguez, Jessicca; Concepción, Juan Luis; Cáceres, Ana; Quiñones, Wilfredo

    2017-10-26

    The current study aimed to determine the seroprevalence of Trypanosoma cruzi infection in Sucre State, Venezuela, and its association with epidemiological risk factors. The cluster sampling design allowed selecting 96 villages and 576 dwellings in the State's 15 municipalities. A total of 2,212 serum samples were analyzed by ELISA, HAI, and IFI. Seroprevalence in Sucre State was 3.12%. Risk factors associated with T. cruzi infection were: accumulated garbage, flooring and wall materials, type of dwelling, living in a house with wattle and daub walls and/or straw roofing, living in a house with risky walls and roofing, risky buildings and wattle and daub outbuildings, poultry inside the human dwelling, and presence of firewood. Infection was associated with individual age, and three seropositive cases were found in individuals less than 15 years of age. Sucre State has epidemiological factors that favor the risk of acquiring T. cruzi infection.

  16. CHARACTERIZATION AND ANTIPARASITIC ACTIVITY OF BENZOPHENONE THIOSEMICARBAZONES ON Trypanosoma brucei brucei

    Directory of Open Access Journals (Sweden)

    Georges C. Accrombessi

    2011-02-01

    Full Text Available The structure of four synthesized thiosemicarbazones, substituted or not, of benzophenone has been confirmed by spectrometrical analysis IR, NMR 1H and 13C. Their anti-trypanosomal activities were evaluated on Trypanosoma brucei brucei. Among these compounds, benzophenone 4 phenyl-3-thiosemicarbazone 4 has the highest activity with the half-inhibitory concentration (IC50 = 8.48 micromolar (µM. Benzophenone 4-methyl-3-thiosemicarbazone 3 and benzophenone thiosemicarbazone 1 showed moderate anti-trypanosomal activity with IC50 values equal to 23.27 µM and 67.17 µM respectively. Benzophenone 2 methyl-3-thiosemicarbazone 2 showed no activity up to IC50 = 371.74 µM.

  17. Enhanced succinic acid production in Aspergillus saccharolyticus by heterologous expression of fumarate reductase from Trypanosoma brucei

    DEFF Research Database (Denmark)

    Yang, Lei; Lübeck, Mette; Ahring, Birgitte K.

    2015-01-01

    production medium as well as the complete medium, but the measured enzyme activities were different depending on the media. Furthermore, a soluble NADH-dependent fumarate reductase gene (frd) from Trypanosoma brucei was inserted and expressed in A. saccharolyticus. The expression of the frd gene led......Aspergillus saccharolyticus exhibits great potential as a cell factory for industrial production of dicarboxylic acids. In the analysis of the organic acid profile, A. saccharolyticus was cultivated in an acid production medium using two different pH conditions. The specific activities...... of the enzymes, pyruvate carboxylase (PYC), malate dehydrogenase (MDH), and fumarase (FUM), involved in the reductive tricarboxylic acid (rTCA) branch, were examined and compared in cells harvested from the acid production medium and a complete medium. The results showed that ambient pH had a significant impact...

  18. Seroprevalence of human Trypanosoma cruzi infection in diferent geografic zones of Chiapas, Mexico.

    Science.gov (United States)

    Mazariego-Arana, M A; Monteón, V M; Ballinas-Verdugo, M A; Hernández-Becerril, N; Alejandre-Aguilar, R; Reyes, P A

    2001-01-01

    A serologic survey was carried out in four different geographic zones of Chiapas, Mexico. A total of 1,333 samples were collected from residents of thirteen communities located on the Coast, Central Mountain, Lacandon Forest and a zone called Mesochiapas. One hundred and fifty one seropositive individuals (11.3%) were identified. Human Trypanosoma cruzi infection was influenced by geography. In the Lacandon Forest and Central Mountains there was a higher seroprevalence 32.1 and 13.8% respectively, than on the coast (1.2%). In Mesochiapas there were no seropositive individuals among the 137 persons tested. An active transmission is probably continuing because seropositive cases (13.8%) were detected in children under 10 years of age. The vector recognized on the Coast was Triatoma dimidiata while in the Lacandon Forest it was Rhodnius prolixus.

  19. Population genetic analysis of Colombian Trypanosoma cruzi isolates revealed by enzyme electrophoretic profiles

    Directory of Open Access Journals (Sweden)

    Manuel Ruiz-Garcia

    2001-01-01

    Full Text Available Although Colombia presents an enormous biological diversity, few studies have been conducted on the population genetics of Trypanosoma cruzi. This study was carried out with 23 Colombian stocks of this protozoa analyzed for 13 isoenzymatic loci. The Hardy-Weinberg equilibrium, the genetic diversity and heterogeneity, the genetic relationships and the possible spatial structure of these 23 Colombian stocks of T. cruzi were estimated. The majority of results obtained are in agreement with a clonal population structure. Nevertheless, two aspects expected in a clonal structure were not discovered in the Colombian T. cruzi stocks. There was an absence of given zymodemes over-represented from a geographical point of view and the presumed temporal stabilizing selective phenomena was not observed either in the Colombian stocks sampled several times through the years of the study. Some hypotheses are discussed in order to explain the results found.

  20. The effect of Bulgarian propolis against Trypanosoma cruzi and during its interaction with host cells

    Directory of Open Access Journals (Sweden)

    Andréia Pires Dantas

    2006-03-01

    Full Text Available Propolis has shown activity against pathogenic microorganisms that cause diseases in humans and animals. The ethanol (Et-Blg and acetone (Ket-Blg extracts from a Bulgarian propolis, with known chemical compositions, presented similar activity against tissue culture-derived amastigotes. The treatment of Trypanosoma cruzi-infected skeletal muscle cells with Et-Blg led to a decrease of infection and of the intracellular proliferation of amastigotes, while damage to the host cell was observed only at concentration 12.5 times higher than those affecting the parasite. Ultrastructural analysis of the effect of both extracts in epimastigotes revealed that the main targets were the mitochondrion and reservosomes. Et-Blg also affected the mitochondrion-kinetoplast complex in trypomastigotes, offering a potential target for chemotherapeutic agents.

  1. The role of adaptations in two-strain competition for sylvatic Trypanosoma cruzi transmission.

    Science.gov (United States)

    Kribs-Zaleta, Christopher M; Mubayi, Anuj

    2012-01-01

    This study presents a continuous-time model for the sylvatic transmission dynamics of two strains of Trypanosoma cruzi enzootic in North America, in order to study the role that adaptations of each strain to distinct modes of transmission (classical stercorarian transmission on the one hand, and vertical and oral transmission on the other) may play in the competition between the two strains. A deterministic model incorporating contact process saturation predicts competitive exclusion, and reproductive numbers for the infection provide a framework for evaluating the competition in terms of adaptive trade-off between distinct transmission modes. Results highlight the importance of oral transmission in mediating the competition between horizontal (stercorarian) and vertical transmission; its presence as a competing contact process advantages vertical transmission even without adaptation to oral transmission, but such adaptation appears necessary to explain the persistence of (vertically-adapted) T. cruzi IV in raccoons and woodrats in the southeastern United States.

  2. Seroprevalence of Trypanosoma cruzi in rural Ecuador and clustering of seropositivity within households.

    Science.gov (United States)

    Black, Carla L; Ocaña-Mayorga, Sofía; Riner, Diana K; Costales, Jaime A; Lascano, Mauricio S; Arcos-Terán, Laura; Preisser, John S; Seed, J Richard; Grijalva, Mario J

    2009-12-01

    We performed a cross-sectional study of Trypanosoma cruzi seroprevalence in 14 communities in three provinces of Ecuador and estimated the magnitude of the association of seropositive individuals within households. A total of 3,286 subjects from 997 households were included. Seroprevalence was 5.7%, 1.0%, and 3.6% in subjects in the Manabí, Guayas, and Loja provinces, respectively. Seroprevalence increased with increasing age in Manabí and Guayas, whereas in Loja, the highest prevalence occurred in children Loja, the odds of seropositivity were more than two times greater for an individual living in a household with another seropositive person. Our results indicate that transmission of T. cruzi is ongoing in Ecuador, although intensity of transmission and mechanisms of interaction between humans and the insect vectors of disease vary between geographic regions.

  3. The Role of Heme and Reactive Oxygen Species in Proliferation and Survival of Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Marcia Cristina Paes

    2011-01-01

    Full Text Available Trypanosoma cruzi, the protozoan responsible for Chagas disease, has a complex life cycle comprehending two distinct hosts and a series of morphological and functional transformations. Hemoglobin degradation inside the insect vector releases high amounts of heme, and this molecule is known to exert a number of physiological functions. Moreover, the absence of its complete biosynthetic pathway in T. cruzi indicates heme as an essential molecule for this trypanosomatid survival. Within the hosts, T. cruzi has to cope with sudden environmental changes especially in the redox status and heme is able to increase the basal production of reactive oxygen species (ROS which can be also produced as byproducts of the parasite aerobic metabolism. In this regard, ROS sensing is likely to be an important mechanism for the adaptation and interaction of these organisms with their hosts. In this paper we discuss the main features of heme and ROS susceptibility in T. cruzi biology.

  4. Trypanosoma brucei gambiense trypanosomiasis in Terego county, northern Uganda, 1996: a lot quality assurance sampling survey.

    Science.gov (United States)

    Hutin, Yvan J F; Legros, Dominique; Owini, Vincent; Brown, Vincent; Lee, Evan; Mbulamberi, Dawson; Paquet, Christophe

    2004-04-01

    We estimated the pre-intervention prevalence of Trypanosoma brucei gambiense (Tbg) trypanosomiasis using the lot quality assurance sampling (LQAS) methods in 14 parishes of Terego County in northern Uganda. A total of 826 participants were included in the survey sample in 1996. The prevalence of laboratory confirmed Tbg trypanosomiasis adjusted for parish population sizes was 2.2% (95% confidence interval =1.1-3.2). This estimate was consistent with the 1.1% period prevalence calculated on the basis of cases identified through passive and active screening in 1996-1999. Ranking of parishes in four categories according to LQAS analysis of the 1996 survey predicted the prevalences observed during the first round of active screening in the population in 1997-1998 (P LQAS were validated by the results of the population screening, suggesting that these survey methods may be useful in the pre-intervention phase of sleeping sickness control programs.

  5. Deciphering RNA Regulatory Elements Involved in the Developmental and Environmental Gene Regulation of Trypanosoma brucei.

    Science.gov (United States)

    Gazestani, Vahid H; Salavati, Reza

    2015-01-01

    Trypanosoma brucei is a vector-borne parasite with intricate life cycle that can cause serious diseases in humans and animals. This pathogen relies on fine regulation of gene expression to respond and adapt to variable environments, with implications in transmission and infectivity. However, the involved regulatory elements and their mechanisms of actions are largely unknown. Here, benefiting from a new graph-based approach for finding functional regulatory elements in RNA (GRAFFER), we have predicted 88 new RNA regulatory elements that are potentially involved in the gene regulatory network of T. brucei. We show that many of these newly predicted elements are responsive to both transcriptomic and proteomic changes during the life cycle of the parasite. Moreover, we found that 11 of predicted elements strikingly resemble previously identified regulatory elements for the parasite. Additionally, comparison with previously predicted motifs on T. brucei suggested the superior performance of our approach based on the current limited knowledge of regulatory elements in T. brucei.

  6. Trypanosoma cruzi in the anal glands of urban opossums: I- isolation and experimental infections

    Directory of Open Access Journals (Sweden)

    S Urdaneta-Morales

    1996-08-01

    Full Text Available Opossums (Didelphis marsupialis captured in intensely urbanized areas of the city of Caracas, Venezuela, were found infected with Trypanosoma cruzi. The developmental cycle of trypomastigote-epimastigote-metacyclic infective trypomastigote, usually occurring in the intestine of the triatomine vector, was taking place in the anal odoriferous glands of the opossums. Material from the glands, inoculated in young, healthy opossums and white mice by different routes, subcutaneously, intraperitoneally, orally, and into the eye, induced T. cruzi infections in all animals. Parasitemia, invasion of cardiac and skeletal muscle, and intracellular multiplication of amastigotes were observed. Inoculation of metacyclics from anal glands, cultured in LIT medium, gave equivalent results. All opossums survived; all mice died. Excreta of opossums may thus transmit Chagas' disease by contamination, even in urban areas where insect vectors are not present.

  7. Mechanism of Trypanosoma cruzi Placenta Invasion and Infection: The Use of Human Chorionic Villi Explants

    Directory of Open Access Journals (Sweden)

    Ricardo E. Fretes

    2012-01-01

    Full Text Available Congenital Chagas disease, a neglected tropical disease, endemic in Latin America, is associated with premature labor and miscarriage. During vertical transmission the parasite Trypanosoma cruzi (T. cruzi crosses the placental barrier. However, the exact mechanism of the placental infection remains unclear. We review the congenital transmission of T. cruzi, particularly the role of possible local placental factors that contribute to the vertical transmission of the parasite. Additionally, we analyze the different methods available for studying the congenital transmission of the parasite. In that context, the ex vivo infection with T. cruzi trypomastigotes of human placental chorionic villi constitutes an excellent tool for studying parasite infection strategies as well as possible local antiparasitic mechanisms.

  8. Transcriptional profiling of cattle infected with Trypanosoma congolense highlights gene expression signatures underlying trypanotolerance and trypanosusceptibility

    Directory of Open Access Journals (Sweden)

    Naessens Jan

    2009-05-01

    Full Text Available Abstract Background African animal trypanosomiasis (AAT caused by tsetse fly-transmitted protozoa of the genus Trypanosoma is a major constraint on livestock and agricultural production in Africa and is among the top ten global cattle diseases impacting on the poor. Here we show that a functional genomics approach can be used to identify temporal changes in host peripheral blood mononuclear cell (PBMC gene expression due to disease progression. We also show that major gene expression differences exist between cattle from trypanotolerant and trypanosusceptible breeds. Using bovine long oligonucleotide microarrays and real time quantitative reverse transcription PCR (qRT-PCR validation we analysed PBMC gene expression in naïve trypanotolerant and trypanosusceptible cattle experimentally challenged with Trypanosoma congolense across a 34-day infection time course. Results Trypanotolerant N'Dama cattle displayed a rapid and distinct transcriptional response to infection, with a ten-fold higher number of genes differentially expressed at day 14 post-infection compared to trypanosusceptible Boran cattle. These analyses identified coordinated temporal gene expression changes for both breeds in response to trypanosome infection. In addition, a panel of genes were identified that showed pronounced differences in gene expression between the two breeds, which may underlie the phenomena of trypanotolerance and trypanosusceptibility. Gene ontology (GO analysis demonstrate that the products of these genes may contribute to increased mitochondrial mRNA translational efficiency, a more pronounced B cell response, an elevated activation status and a heightened response to stress in trypanotolerant cattle. Conclusion This study has revealed an extensive and diverse range of cellular processes that are altered temporally in response to trypanosome infection in African cattle. Results indicate that the trypanotolerant N'Dama cattle respond more rapidly and with a

  9. Prevalencia de infeccion a Trypanosoma cruzi en donadores de sangre en el Estado de Jalisco, Mexico

    Directory of Open Access Journals (Sweden)

    Francisco Trujillo Contreras

    1993-06-01

    Full Text Available Durante el periodo de Octubre de 1991 a Marzo de 1992, se tomaron 3419 muestras de donadores de sangre de 12 localidades rurales y de 8 hospitales urbanos a los que se les realizo un estúdio serológico mediante la reacción de hemaglutinación indirecta encontrándose anticuerpos contra Trypanosoma cruzi en 44 indivíduos 39 masculinosy 5 femininos. El 90,9% de donantes fueron masculinos. De acuerdo a su procedencia, el 73,5% fué del área urbana y el 26,5% del área rural. De acuerdo a los resultados el riesgo de transmisión de T. cruzi por transfusión sanguinea está latente por la creciente urbanización de la enfermedad de Chagas.A Chagas Disease serological study was done frorn October 1991 to March 1992 and 3419 samples were takenfrom people who donated blood at 12 county areas of Jalisco, México and 8 urban hospitais, by means of indirect hemagglutination reaction. The results indicate that: 73.5% of the donors were from urban area, 26.5% were from rural areas; 1.28% of the donors (N=44 were considered infected. Thirty nine of them (1.14 were males and 5 females. According to the above mentioned data, we can confirm that the risk of transmission of Trypanosoma cruzi can occur by blood transfusion and this is potentially latent because of the growing urbanization of Chagas disease.

  10. Interactions between 4-aminoquinoline and heme: Promising mechanism against Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Guilherme Curty Lechuga

    2016-12-01

    Full Text Available Chagas disease is a neglected tropical disease caused by the flagellated protozoan Trypanosoma cruzi. The current drugs used to treat this disease have limited efficacy and produce severe side effects. Quinolines, nitrogen heterocycle compounds that form complexes with heme, have a broad spectrum of antiprotozoal activity and are a promising class of new compounds for Chagas disease chemotherapy. In this study, we evaluated the activity of a series of 4-arylaminoquinoline-3-carbonitrile derivatives against all forms of Trypanosoma cruzi in vitro. Compound 1g showed promising activity against epimastigote forms when combined with hemin (IC50<1 μM, with better performance than benznidazole, the reference drug. This compound also inhibited the viability of trypomastigotes and intracellular amastigotes. The potency of 1g in combination with heme was enhanced against epimastigotes and trypomastigotes, suggesting a similar mechanism of action that occurs in Plasmodium spp. The addition of hemin to the culture medium increased trypanocidal activity of analog 1g without changing the cytotoxicity of the host cell, reaching an IC50 of 11.7 μM for trypomastigotes. The mechanism of action was demonstrated by the interaction of compound 1g with hemin in solution and prevention of heme peroxidation. Compound 1g and heme treatment induced alterations of the mitochondrion-kinetoplast complex in epimastigotes and trypomastigotes and also, accumulation of electron-dense deposits in amastigotes as visualized by transmission electron microscopy. The trypanocidal activity of 4-aminoquinolines and the elucidation of the mechanism involving interaction with heme is a neglected field of research, given the parasite's lack of heme biosynthetic pathway and the importance of this cofactor for parasite survival and growth. The results of this study can improve and guide rational drug development and combination treatment strategies.

  11. Stearoyl-CoA desaturase is an essential enzyme for the parasitic protist Trypanosoma brucei

    Energy Technology Data Exchange (ETDEWEB)

    Alloatti, Andres [Instituto de Biologia Molecular y Celular de Rosario (IBR), CONICET, Facultad de Ciencias Bioquimicas y Farmaceuticas, Universidad Nacional de Rosario, Santa Fe (Argentina); Gupta, Shreedhara; Gualdron-Lopez, Melisa; Nguewa, Paul A. [Research Unit for Tropical Diseases, de Duve Institute and Laboratory of Biochemistry, Universite Catholique de Louvain, Brussels (Belgium); Altabe, Silvia G. [Instituto de Biologia Molecular y Celular de Rosario (IBR), CONICET, Facultad de Ciencias Bioquimicas y Farmaceuticas, Universidad Nacional de Rosario, Santa Fe (Argentina); Deumer, Gladys; Wallemacq, Pierre [Department of Clinical Chemistry, Cliniques Universitaires Saint-Luc, LTAP, Universite Catholique de Louvain, Brussels (Belgium); Michels, Paul A.M. [Research Unit for Tropical Diseases, de Duve Institute and Laboratory of Biochemistry, Universite Catholique de Louvain, Brussels (Belgium); Uttaro, Antonio D., E-mail: toniuttaro@yahoo.com.ar [Instituto de Biologia Molecular y Celular de Rosario (IBR), CONICET, Facultad de Ciencias Bioquimicas y Farmaceuticas, Universidad Nacional de Rosario, Santa Fe (Argentina)

    2011-08-26

    Highlights: {yields} Inhibiting {Delta}9 desaturase drastically changes T. brucei's fatty-acid composition. {yields} Isoxyl specifically inhibits the {Delta}9 desaturase causing a growth arrest. {yields} RNA interference of desaturase expression causes a similar effect. {yields} Feeding T. brucei-infected mice with Isoxyl decreases the parasitemia. {yields} 70% of Isoxyl-treated mice survived the trypanosome infection. -- Abstract: Trypanosoma brucei, the etiologic agent of sleeping sickness, is exposed to important changes in nutrients and temperature during its life cycle. To adapt to these changes, the fluidity of its membranes plays a crucial role. This fluidity, mediated by the fatty-acid composition, is regulated by enzymes named desaturases. We have previously shown that the oleoyl desaturase is essential for Trypanosoma cruzi and T. brucei. In this work, we present experimental support for the relevance of stearoyl-CoA desaturase (SCD) for T. brucei's survival, in both its insect or procyclic-form (PCF) and bloodstream-form (BSF) stages. We evaluated this essentiality in two different ways: by generating a SCD knocked-down parasite line using RNA interference, and by chemical inhibition of the enzyme with two compounds, Isoxyl and a thiastearate with the sulfur atom at position 10 (10-TS). The effective concentration for 50% growth inhibition (EC{sub 50}) of PCF was 1.0 {+-} 0.2 {mu}M for Isoxyl and 5 {+-} 2 {mu}M for 10-TS, whereas BSF appeared more susceptible with EC{sub 50} values 0.10 {+-} 0.03 {mu}M (Isoxyl) and 1.0 {+-} 0.6 {mu}M (10-TS). RNA interference showed to be deleterious for both stages of the parasite. In addition, T. brucei-infected mice were fed with Isoxyl, causing a reduction of the parasitemia and an increase of the rodents' survival.

  12. Trypanosoma cruzi Detection in Colombian Patients with a Diagnosis of Esophageal Achalasia.

    Science.gov (United States)

    Panesso-Gómez, Santiago; Pavia, Paula; Rodríguez-Mantilla, Iván Enrique; Lasso, Paola; Orozco, Luis A; Cuellar, Adriana; Puerta, Concepción J; Mendoza de Molano, Belén; González, John M

    2018-03-01

    Achalasia is a motility disorder of the esophagus that might be secondary to a chronic Trypanosoma cruzi infection. Several studies have investigated esophageal achalasia in patients with Chagas disease (CD) in Latin America, but no related studies have been performed in Colombia. The goals of the present study were to determine the presence of anti- T. cruzi antibodies in patients with esophageal achalasia who visited a referral hospital in Bogotá, Colombia, and to detect the presence of the parasite and its discrete typing units (DTUs). This cross-sectional study was conducted in adult patients (18-65 years old) who were previously diagnosed with esophageal achalasia and from whom blood was drawn to assess antibodies against T. cruzi using four different serological tests. Trypanosoma cruzi DNA was detected by conventional polymerase chain reaction (cPCR) and quantitative polymerase chain reaction (qPCR). In total, 38 patients, with an average age of 46.6 years (standard deviation of ±16.2) and comprising 16 men and 22 women, were enrolled. Five (13.15%) patients were found to be positive for anti- T. cruzi antibodies by indirect immunofluorescence assay (IFA), and two patients who were negative according to IFA were reactive by both enzyme-linked immunosorbent assay and immunoblot (5.3%). Parasite DNA was detected in two of these seven patients by cPCR and in one of these by qPCR. The parasite DTU obtained was TcI. In summary, this study identified T. cruzi in Colombian patients with esophageal achalasia, indicating that digestive compromise could also be present in patients with chronic CD.

  13. Interactions between 4-aminoquinoline and heme: Promising mechanism against Trypanosoma cruzi.

    Science.gov (United States)

    Lechuga, Guilherme Curty; Borges, Júlio Cesar; Calvet, Claudia Magalhães; de Araújo, Humberto Pinheiro; Zuma, Aline Araujo; do Nascimento, Samara Braga; Motta, Maria Cristina Machado; Bernardino, Alice Maria Rolim; Pereira, Mirian Claudia de Souza; Bourguignon, Saulo Cabral

    2016-12-01

    Chagas disease is a neglected tropical disease caused by the flagellated protozoan Trypanosoma cruzi. The current drugs used to treat this disease have limited efficacy and produce severe side effects. Quinolines, nitrogen heterocycle compounds that form complexes with heme, have a broad spectrum of antiprotozoal activity and are a promising class of new compounds for Chagas disease chemotherapy. In this study, we evaluated the activity of a series of 4-arylaminoquinoline-3-carbonitrile derivatives against all forms of Trypanosoma cruzi in vitro. Compound 1g showed promising activity against epimastigote forms when combined with hemin (IC50<1 μM), with better performance than benznidazole, the reference drug. This compound also inhibited the viability of trypomastigotes and intracellular amastigotes. The potency of 1g in combination with heme was enhanced against epimastigotes and trypomastigotes, suggesting a similar mechanism of action that occurs in Plasmodium spp. The addition of hemin to the culture medium increased trypanocidal activity of analog 1g without changing the cytotoxicity of the host cell, reaching an IC50 of 11.7 μM for trypomastigotes. The mechanism of action was demonstrated by the interaction of compound 1g with hemin in solution and prevention of heme peroxidation. Compound 1g and heme treatment induced alterations of the mitochondrion-kinetoplast complex in epimastigotes and trypomastigotes and also, accumulation of electron-dense deposits in amastigotes as visualized by transmission electron microscopy. The trypanocidal activity of 4-aminoquinolines and the elucidation of the mechanism involving interaction with heme is a neglected field of research, given the parasite's lack of heme biosynthetic pathway and the importance of this cofactor for parasite survival and growth. The results of this study can improve and guide rational drug development and combination treatment strategies. Copyright © 2016 The Authors. Published by Elsevier

  14. The Effectiveness of Natural Diarylheptanoids against Trypanosoma cruzi: Cytotoxicity, Ultrastructural Alterations and Molecular Modeling Studies.

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    Vitor Sueth-Santiago

    Full Text Available Curcumin (CUR is the major constituent of the rhizomes of Curcuma longa and has been widely investigated for its chemotherapeutic properties. The well-known activity of CUR against Leishmania sp., Trypanosoma brucei and Plasmodium falciparum led us to investigate its activity against Trypanosoma cruzi. In this work, we tested the cytotoxic effects of CUR and other natural curcuminoids on different forms of T. cruzi, as well as the ultrastructural changes induced in epimastigote form of the parasite. CUR was verified as the curcuminoid with more significant trypanocidal properties (IC50 10.13 μM on epimastigotes. Demethoxycurcumin (DMC was equipotent to CUR (IC50 11.07 μM, but bisdemethoxycurcumin (BDMC was less active (IC50 45.33 μM and cyclocurcumin (CC was inactive. In the experiment with infected murine peritoneal macrophages all diarylheptanoids were more active than the control in the inhibition of the trypomastigotes release. The electron microscopy images showed ultrastructural changes associated with the cytoskeleton of the parasite, indicating tubulin as possible target of CUR in T. cruzi. The results obtained by flow cytometry analysis of DNA content of the parasites treated with natural curcuminoids suggested a mechanism of action on microtubules related to the paclitaxel`s mode of action. To better understand the mechanism of action highlighted by electron microscopy and flow cytometry experiments we performed the molecular docking of natural curcuminoids on tubulin of T. cruzi in a homology model and the results obtained showed that the observed interactions are in accordance with the IC50 values found, since there CUR and DMC perform similar interactions at the binding site on tubulin while BDMC do not realize a hydrogen bond with Lys163 residue due to the absence of methoxyl groups. These results indicate that trypanocidal properties of CUR may be related to the cytoskeletal alterations.

  15. Population genetics of Trypanosoma brucei rhodesiense: clonality and diversity within and between foci.

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    Craig W Duffy

    2013-11-01

    Full Text Available African trypanosomes are unusual among pathogenic protozoa in that they can undergo their complete morphological life cycle in the tsetse fly vector with mating as a non-obligatory part of this development. Trypanosoma brucei rhodesiense, which infects humans and livestock in East and Southern Africa, has classically been described as a host-range variant of the non-human infective Trypanosoma brucei that occurs as stable clonal lineages. We have examined T. b. rhodesiense populations from East (Uganda and Southern (Malawi Africa using a panel of microsatellite markers, incorporating both spatial and temporal analyses. Our data demonstrate that Ugandan T. b. rhodesiense existed as clonal populations, with a small number of highly related genotypes and substantial linkage disequilibrium between pairs of loci. However, these populations were not stable as the dominant genotypes changed and the genetic diversity also reduced over time. Thus these populations do not conform to one of the criteria for strict clonality, namely stability of predominant genotypes over time, and our results show that, in a period in the mid 1990s, the previously predominant genotypes were not detected but were replaced by a novel clonal population with limited genetic relationship to the original population present between 1970 and 1990. In contrast, the Malawi T. b. rhodesiense population demonstrated significantly greater diversity and evidence for frequent genetic exchange. Therefore, the population genetics of T. b. rhodesiense is more complex than previously described. This has important implications for the spread of the single copy T. b. rhodesiense gene that allows human infectivity, and therefore the epidemiology of the human disease, as well as suggesting that these parasites represent an important organism to study the influence of optional recombination upon population genetic dynamics.

  16. Heme A synthesis and CcO activity are essential for Trypanosoma cruzi infectivity and replication.

    Science.gov (United States)

    Merli, Marcelo L; Cirulli, Brenda A; Menéndez-Bravo, Simón M; Cricco, Julia A

    2017-06-27

    Trypanosoma cruzi , the causative agent of Chagas disease, presents a complex life cycle and adapts its metabolism to nutrients' availability. Although T. cruzi is an aerobic organism, it does not produce heme. This cofactor is acquired from the host and is distributed and inserted into different heme-proteins such as respiratory complexes in the parasite's mitochondrion. It has been proposed that T. cruzi's energy metabolism relies on a branched respiratory chain with a cytochrome c oxidase-type aa 3 (C c O) as the main terminal oxidase. Heme A, the cofactor for all eukaryotic C c O, is synthesized via two sequential enzymatic reactions catalyzed by heme O synthase (HOS) and heme A synthase (HAS). Previously, TcCox10 and TcCox15 ( Trypanosoma cruzi Cox10 and Cox15 proteins) were identified in T. cruzi They presented HOS and HAS activity, respectively, when they were expressed in yeast. Here, we present the first characterization of TcCox15 in T. cruzi , confirming its role as HAS. It was differentially detected in the different T. cruzi stages, being more abundant in the replicative forms. This regulation could reflect the necessity of more heme A synthesis, and therefore more C c O activity at the replicative stages. Overexpression of a non-functional mutant caused a reduction in heme A content. Moreover, our results clearly showed that this hindrance in the heme A synthesis provoked a reduction on C c O activity and, in consequence, an impairment on T. cruzi survival, proliferation and infectivity. This evidence supports that T. cruzi depends on the respiratory chain activity along its life cycle, being C c O an essential terminal oxidase. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  17. Chemical characterisation of Nigerian red propolis and its biological activity against Trypanosoma Brucei.

    Science.gov (United States)

    Omar, Ruwida M K; Igoli, John; Gray, Alexander I; Ebiloma, Godwin Unekwuojo; Clements, Carol; Fearnley, James; Ebel, Ru Angeli Edrada; Zhang, Tong; De Koning, Harry P; Watson, David G

    2016-01-01

    A previous study showed the unique character of Nigerian red propolis from Rivers State, Nigeria (RSN), with regards to chemical composition and activity against Trypanosoma brucei in comparison with other African propolis. To carry out fractionation and biological testing of Nigerian propolis in order to isolate compounds with anti-trypanosomal activity. To compare the composition of the RSN propolis with the composition of Brazilian red propolis. Profiling was carried out using HPLC-UV-ELSD and HPLC-Orbitrap-FTMS on extracts of two samples collected from RSN with data extraction using MZmine software. Isolation was carried out by normal phase and reversed phase MPLC. Elucidation of the compounds with a purity > 95% was performed by 1D/2D NMR HRMS and HRLC-MS(n) . Ten phenolic compounds were isolated or in the case of liquiritigenin partially purified. Data for nine of these correlated with literature reports of known compounds i.e. one isoflavanone, calycosin (1); two flavanones, liquiritigenin (2) and pinocembrin (5); an isoflavan, vestitol (3); a pterocarpan, medicarpin (4); two prenylflavanones, 8-prenylnaringenin (7) and 6-prenylnaringenin (8); and two geranyl flavonoids, propolin D (9) and macarangin (10). The tenth was elucidated as a previously undescribed dihydrobenzofuran (6). The isolated compounds were tested against Trypanosoma brucei and displayed moderate to high activity. Some of the compounds tested had similar activity against wild type T. brucei and two strains displaying pentamidine resistance. Nigerian propolis from RSN has some similarities with Brazilian red propolis. The propolis displayed anti-trypanosomal activity at a potentially useful level. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Congenital transmission of Trypanosoma cruzi in Argentina, Honduras, and Mexico: study protocol

    Science.gov (United States)

    2013-01-01

    Background Trypanosoma cruzi has been divided into Discrete Typing Units I and non-I (II-VI). T. cruzi I is predominant in Mexico and Central America, while non-I is predominant in most of South America, including Argentina. Little is known about congenital transmission of T. cruzi I. The specific aim of this study is to determine the rate of congenital transmission of T. cruzi I compared to non-I. Methods/design We are conducting a prospective study to enroll at delivery, 10,000 women in Argentina, 7,500 women in Honduras, and 13,000 women in Mexico. We are measuring transmitted maternal T. cruzi antibodies by performing two rapid tests in cord blood (Stat-Pak, Chembio, Medford, New York, and Trypanosoma Detect, InBios, Seattle, Washington). If at least one of the results is positive, we are identifying infants who are congenitally infected by performing parasitological examinations on cord blood and at 4–8 weeks, and serological follow-up at 10 months. Serological confirmation by ELISA (Wiener, Rosario, Argentina) is performed in cord and maternal blood, and at 10 months. We also are performing T. cruzi standard PCR, real-time quantitative PCR and genotyping on maternal venous blood and on cord blood, and serological examinations on siblings. Data are managed by a Data Center in Montevideo, Uruguay. Data are entered online at the sites in an OpenClinica data management system, and digital pictures of data forms are sent to the Data Center for quality control. Weekly reports allow for rapid feedback to the sites. Trial registration Observational study with ClinicalTrials.gov Identifier NCT01787968 PMID:24119247

  19. Stearoyl-CoA desaturase is an essential enzyme for the parasitic protist Trypanosoma brucei

    International Nuclear Information System (INIS)

    Alloatti, Andres; Gupta, Shreedhara; Gualdron-Lopez, Melisa; Nguewa, Paul A.; Altabe, Silvia G.; Deumer, Gladys; Wallemacq, Pierre; Michels, Paul A.M.; Uttaro, Antonio D.

    2011-01-01

    Highlights: → Inhibiting Δ9 desaturase drastically changes T. brucei's fatty-acid composition. → Isoxyl specifically inhibits the Δ9 desaturase causing a growth arrest. → RNA interference of desaturase expression causes a similar effect. → Feeding T. brucei-infected mice with Isoxyl decreases the parasitemia. → 70% of Isoxyl-treated mice survived the trypanosome infection. -- Abstract: Trypanosoma brucei, the etiologic agent of sleeping sickness, is exposed to important changes in nutrients and temperature during its life cycle. To adapt to these changes, the fluidity of its membranes plays a crucial role. This fluidity, mediated by the fatty-acid composition, is regulated by enzymes named desaturases. We have previously shown that the oleoyl desaturase is essential for Trypanosoma cruzi and T. brucei. In this work, we present experimental support for the relevance of stearoyl-CoA desaturase (SCD) for T. brucei's survival, in both its insect or procyclic-form (PCF) and bloodstream-form (BSF) stages. We evaluated this essentiality in two different ways: by generating a SCD knocked-down parasite line using RNA interference, and by chemical inhibition of the enzyme with two compounds, Isoxyl and a thiastearate with the sulfur atom at position 10 (10-TS). The effective concentration for 50% growth inhibition (EC 50 ) of PCF was 1.0 ± 0.2 μM for Isoxyl and 5 ± 2 μM for 10-TS, whereas BSF appeared more susceptible with EC 50 values 0.10 ± 0.03 μM (Isoxyl) and 1.0 ± 0.6 μM (10-TS). RNA interference showed to be deleterious for both stages of the parasite. In addition, T. brucei-infected mice were fed with Isoxyl, causing a reduction of the parasitemia and an increase of the rodents' survival.

  20. Trypanosoma Infection Favors Brucella Elimination via IL-12/IFNγ-Dependent Pathways

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    Arnaud Machelart

    2017-07-01

    Full Text Available This study develops an original co-infection model in mice using Brucella melitensis, the most frequent cause of human brucellosis, and Trypanosoma brucei, the agent of African trypanosomiasis. Although the immunosuppressive effects of T. brucei in natural hosts and mice models are well established, we observed that the injection of T. brucei in mice chronically infected with B. melitensis induces a drastic reduction in the number of B. melitensis in the spleen, the main reservoir of the infection. Similar results are obtained with Brucella abortus- and Brucella suis-infected mice and B. melitensis-infected mice co-infected with Trypanosoma cruzi, demonstrating that this phenomenon is not due to antigenic cross-reactivity. Comparison of co-infected wild-type and genetically deficient mice showed that Brucella elimination required functional IL-12p35/IFNγ signaling pathways and the presence of CD4+ T cells. However, the impact of wild type and an attenuated mutant of T. brucei on B. melitensis were similar, suggesting that a chronic intense inflammatory reaction is not required to eliminate B. melitensis. Finally, we also tested the impact of T. brucei infection on the course of Mycobacterium tuberculosis infection. Although T. brucei strongly increases the frequency of IFNγ+CD4+ T cells, it does not ameliorate the control of M. tuberculosis infection, suggesting that it is not controlled by the same effector mechanisms as Brucella. Thus, whereas T. brucei infections are commonly viewed as immunosuppressive and pathogenic, our data suggest that these parasites can specifically affect the immune control of Brucella infection, with benefits for the host.

  1. High Trypanosoma cruzi infection prevalence associated with minimal cardiac pathology among wild carnivores in central Texas

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    Rachel Curtis-Robles

    2016-08-01

    Full Text Available Infection with the zoonotic vector-borne protozoal parasite Trypanosoma cruzi causes Chagas disease in humans and dogs throughout the Americas. Despite the recognized importance of various wildlife species for perpetuating Trypanosoma cruzi in nature, relatively little is known about the development of cardiac disease in infected wildlife. Using a cross-sectional study design, we collected cardiac tissue and blood from hunter-donated wildlife carcasses- including raccoon (Procyon lotor, coyote (Canis latrans, gray fox (Urocyon cinereoargenteus, and bobcat (Lynx rufus – from central Texas, a region with established populations of infected triatomine vectors and increasing diagnoses of Chagas disease in domestic dogs. Based on PCR analysis, we found that 2 bobcats (14.3%, 12 coyotes (14.3%, 8 foxes (13.8%, and 49 raccoons (70.0% were positive for T. cruzi in at least one sample (right ventricle, apex, and/or blood clot. Although a histologic survey of right ventricles showed that 21.1% of 19 PCR-positive hearts were characterized by mild lymphoplasmocytic infiltration, no other lesions and no amastigotes were observed in any histologic section. DNA sequencing of the TcSC5D gene revealed that raccoons were infected with T. cruzi strain TcIV, and a single racoon harbored a TcI/TcIV mixed infection. Relative to other wildlife species tested here, our data suggest that raccoons may be important reservoirs of TcIV in Texas and a source of infection for indigenous triatomine bugs. The overall high level of infection in this wildlife community likely reflects high levels of vector contact, including ingestion of bugs. Although the relationship between the sylvatic cycle of T. cruzi transmission and human disease risk in the United States has yet to be defined, our data suggest that hunters and wildlife professionals should take precautions to avoid direct contact with potentially infected wildlife tissues.

  2. Epidemiology of Babesia, Anaplasma and Trypanosoma species using a new expanded reverse line blot hybridization assay.

    Science.gov (United States)

    Paoletta, Martina Soledad; López Arias, Ludmila; de la Fournière, Sofía; Guillemi, Eliana Carolina; Luciani, Carlos; Sarmiento, Néstor Fabián; Mosqueda, Juan; Farber, Marisa Diana; Wilkowsky, Silvina Elizabeth

    2018-02-01

    Vector-borne hemoparasitic infections are a major problem that affects livestock industries worldwide, particularly in tropical and subtropical regions. In this work, a reverse line blot (RLB) hybridization assay was developed for the simultaneous detection and identification of Anaplasma, Babesia and bovine trypanosomes, encompassing in this way the most relevant hemoparasites that affect cattle. A total of 186 bovine blood samples collected from two different ecoepidemiological regions of northeast Argentina, with and without tick control, were analyzed with this new RLB. High diversity of parasites, such as Babesia bovis, B. bigemina, Anaplasma marginale and three different Trypanosoma species, was found. High rates of coinfections were also detected, and significant differences were observed not only in the prevalence of parasites but also in the level of coinfections between the two analyzed areas. Regarding the Trypanosoma genus, we provide molecular evidence of the presence of T. vivax and T. theileri for the first time in Argentina. Besides, since the RLB is a prospective tool, it allowed the identification of a yet unknown bovine trypanosome which could not be assigned to any of the bovine species known so far. In the present study we provide new insights on the prevalence of several pathogens that directly impact on livestock production in Argentina. The RLB assay developed here allows to identify simultaneously numerous pathogenic species which can also be easily expanded to detect other blood borne pathogens. These characteristics make the RLB hybridization assay an essential tool for epidemiological survey of all vector-borne pathogens. Copyright © 2017 Elsevier GmbH. All rights reserved.

  3. Projected future distributions of vectors of Trypanosoma cruzi in North America under climate change scenarios.

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    Miroslava Garza

    2014-05-01

    Full Text Available Chagas disease kills approximately 45 thousand people annually and affects 10 million people in Latin America and the southern United States. The parasite that causes the disease, Trypanosoma cruzi, can be transmitted by insects of the family Reduviidae, subfamily Triatominae. Any study that attempts to evaluate risk for Chagas disease must focus on the ecology and biogeography of these vectors. Expected distributional shifts of vector species due to climate change are likely to alter spatial patterns of risk of Chagas disease, presumably through northward expansion of high risk areas in North America.We forecast the future (2050 distributions in North America of Triatoma gerstaeckeri and T. sanguisuga, two of the most common triatomine species and important vectors of Trypanosoma cruzi in the southern United States. Our aim was to analyze how climate change might affect the future shift of Chagas disease in North America using a maximum entropy algorithm to predict changes in suitable habitat based on vector occurrence points and predictive environmental variables. Projections based on three different general circulation models (CCCMA, CSIRO, and HADCM3 and two IPCC scenarios (A2 and B2 were analyzed. Twenty models were developed for each case and evaluated via cross-validation. The final model averages result from all twenty of these models. All models had AUC >0.90, which indicates that the models are robust. Our results predict a potential northern shift in the distribution of T. gerstaeckeri and a northern and southern distributional shift of T. sanguisuga from its current range due to climate change.The results of this study provide baseline information for monitoring the northward shift of potential risk from Chagas disease in the face of climate change.

  4. Trypanosoma janseni n. sp. (Trypanosomatida: Trypanosomatidae isolated from Didelphis aurita (Mammalia: Didelphidae in the Atlantic Rainforest of Rio de Janeiro, Brazil: integrative taxonomy and phylogeography within the Trypanosoma cruzi clade

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    Camila Madeira Tavares Lopes

    Full Text Available BACKGROUND Didelphis spp. are a South American marsupial species that are among the most ancient hosts for the Trypanosoma spp. OBJECTIVES We characterise a new species (Trypanosoma janseni n. sp. isolated from the spleen and liver tissues of Didelphis aurita in the Atlantic Rainforest of Rio de Janeiro, Brazil. METHODS The parasites were isolated and a growth curve was performed in NNN and Schneider's media containing 10% foetal bovine serum. Parasite morphology was evaluated via light microscopy on Giemsa-stained culture smears, as well as scanning and transmission electron microscopy. Molecular taxonomy was based on a partial region (737-bp of the small subunit (18S ribosomal RNA gene and 708 bp of the nuclear marker, glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH genes. Maximum likelihood and Bayesian inference methods were used to perform a species coalescent analysis and to generate individual and concatenated gene trees. Divergence times among species that belong to the T. cruzi clade were also inferred. FINDINGS In vitro growth curves demonstrated a very short log phase, achieving a maximum growth rate at day 3 followed by a sharp decline. Only epimastigote forms were observed under light and scanning microscopy. Transmission electron microscopy analysis showed structures typical to Trypanosoma spp., except one structure that presented as single-membraned, usually grouped in stacks of three or four. Phylogeography analyses confirmed the distinct species status of T. janseni n. sp. within the T. cruzi clade. Trypanosoma janseni n. sp. clusters with T. wauwau in a well-supported clade, which is exclusive and monophyletic. The separation of the South American T. wauwau + T. janseni coincides with the separation of the Southern Super Continent. CONCLUSIONS This clade is a sister group of the trypanosomes found in Australian marsupials and its discovery sheds light on the initial diversification process based on what we currently

  5. Trypanosoma janseni n. sp. (Trypanosomatida: Trypanosomatidae) isolated from Didelphis aurita (Mammalia: Didelphidae) in the Atlantic Rainforest of Rio de Janeiro, Brazil: integrative taxonomy and phylogeography within the Trypanosoma cruzi clade.

    Science.gov (United States)

    Lopes, Camila Madeira Tavares; Menna-Barreto, Rubem Figueiredo Sadok; Pavan, Márcio Galvão; Pereira, Mirian Cláudia De Souza; Roque, André Luiz R

    2018-01-01

    Didelphis spp. are a South American marsupial species that are among the most ancient hosts for the Trypanosoma spp. We characterise a new species (Trypanosoma janseni n. sp.) isolated from the spleen and liver tissues of Didelphis aurita in the Atlantic Rainforest of Rio de Janeiro, Brazil. The parasites were isolated and a growth curve was performed in NNN and Schneider's media containing 10% foetal bovine serum. Parasite morphology was evaluated via light microscopy on Giemsa-stained culture smears, as well as scanning and transmission electron microscopy. Molecular taxonomy was based on a partial region (737-bp) of the small subunit (18S) ribosomal RNA gene and 708 bp of the nuclear marker, glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) genes. Maximum likelihood and Bayesian inference methods were used to perform a species coalescent analysis and to generate individual and concatenated gene trees. Divergence times among species that belong to the T. cruzi clade were also inferred. In vitro growth curves demonstrated a very short log phase, achieving a maximum growth rate at day 3 followed by a sharp decline. Only epimastigote forms were observed under light and scanning microscopy. Transmission electron microscopy analysis showed structures typical to Trypanosoma spp., except one structure that presented as single-membraned, usually grouped in stacks of three or four. Phylogeography analyses confirmed the distinct species status of T. janseni n. sp. within the T. cruzi clade. Trypanosoma janseni n. sp. clusters with T. wauwau in a well-supported clade, which is exclusive and monophyletic. The separation of the South American T. wauwau + T. janseni coincides with the separation of the Southern Super Continent. This clade is a sister group of the trypanosomes found in Australian marsupials and its discovery sheds light on the initial diversification process based on what we currently know about the T. cruzi clade.

  6. Momentos em freios e em embraiagens

    OpenAIRE

    Mimoso, Rui Miguel Pereira

    2011-01-01

    Dissertação para obtenção do Grau de Mestre em Mestrado Integrado em Engenharia Mecânica Nesta dissertação reúnem-se os modelos de cálculo utilizados na determinação dos momentos em freios e em embraiagens. Neste trabalho consideram-se os casos de freios e embraiagens de atrito seco e atrito viscoso. Nos freios de atrito viscoso são considerados casos em que as características dos fluidos não são induzidas, e outros em que são induzidas modificações a essas mesmas características. São a...

  7. Distribuição espacial de populações de triatomíneos (Hemiptera: Reduviidae em palmeiras da espécie Mauritia flexuosa no Distrito Federal, Brasil Spatial distribution of Triatominae populations (Hemiptera: Reduviidae in Mauritia flexuosa palm trees in Federal District of Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Gurgel-Gonçalves

    2004-06-01

    Full Text Available Para determinar e analisar a distribuição espacial de populações silvestres de triatomíneos no Distrito Federal, Brasil, foram amostradas 150 palmeiras da espécie Mauritia flexuosa em seis veredas de diferentes paisagens (silvestre, rural e periurbana na estação chuvosa. Os triatomíneos foram identificados morfologicamente, separados por sexo e estadio ninfal e examinados para verificar infecção por Trypanosoma cruzi e Trypanosoma rangeli. Vinte e oito (18,6% palmeiras estavam infestadas por Rhodnius neglectus e 14 (9,5% por Psammolestes tertius. A freqüência dessas espécies em palmeiras com e sem ninhos foi significativamente diferente, sendo superior nas palmeiras com ninhos de aves e mamíferos na copa. O maior número médio de insetos/palmeira foi observado nas áreas rurais, com estimativas de até 838 insetos/hectare. A composição etária das espécies apresentou um padrão diferente, Rhodnius neglectus com predomínio de ninfas e Psammolestes tertius com predomínio de adultos, sendo que muitos ovos de Rhodnius neglectus foram coletados indicando um evento reprodutivo em fevereiro de 2003. Entre os ninhos encontrados nas palmeiras, o do pássaro Phacellodomus ruber (Furnariidae apresentou as maiores abundâncias de triatomíneos, ocorrendo em 42% das palmeiras. A abundância relativa de Rhodnius neglectus e Psammolestes tertius foi maior em áreas rurais que possuíram maior número de ninhos nas palmeiras e menor densidade de palmeiras por hectare. Nenhum dos 96 triatomíneos examinados estava infectado por Trypanosoma cruzi ou Trypanosoma rangeli, apesar de encontrarmos infecção de Rhodnius neglectus por esses parasitas em estudos anteriores.To determine and analyze the distribution of Triatominae sylvatic populations in the Federal District of Brazil, 150 Mauritia flexuosa palm trees were sampled in six veredas of different landscapes (sylvatic, rural and peri-urban in the rainy season. Triatomines were

  8. Repurposing a Library of Human Cathepsin L Ligands: Identification of Macrocyclic Lactams as Potent Rhodesain and Trypanosoma brucei Inhibitors.

    Science.gov (United States)

    Giroud, Maude; Dietzel, Uwe; Anselm, Lilli; Banner, David; Kuglstatter, Andreas; Benz, Jörg; Blanc, Jean-Baptiste; Gaufreteau, Delphine; Liu, Haixia; Lin, Xianfeng; Stich, August; Kuhn, Bernd; Schuler, Franz; Kaiser, Marcel; Brun, Reto; Schirmeister, Tanja; Kisker, Caroline; Diederich, François; Haap, Wolfgang

    2018-04-26

    Rhodesain (RD) is a parasitic, human cathepsin L (hCatL) like cysteine protease produced by Trypanosoma brucei ( T. b.) species and a potential drug target for the treatment of human African trypanosomiasis (HAT). A library of hCatL inhibitors was screened, and macrocyclic lactams were identified as potent RD inhibitors ( K i < 10 nM), preventing the cell-growth of Trypanosoma brucei rhodesiense (IC 50 < 400 nM). SARs addressing the S2 and S3 pockets of RD were established. Three cocrystal structures with RD revealed a noncovalent binding mode of this ligand class due to oxidation of the catalytic Cys25 to a sulfenic acid (Cys-SOH) during crystallization. The P-glycoprotein efflux ratio was measured and the in vivo brain penetration in rats determined. When tested in vivo in acute HAT model, the compounds permitted up to 16.25 (vs 13.0 for untreated controls) mean days of survival.

  9. 3-H-[1,2]Dithiole as a New Anti-Trypanosoma cruzi Chemotype: Biological and Mechanism of Action Studies

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    Marcos Couto

    2015-08-01

    Full Text Available The current pharmacological Chagas disease treatments, using Nifurtimox or Benznidazole, show limited therapeutic results and are associated with potential side effects, like mutagenicity. Using random screening we have identified new chemotypes that were able to inhibit relevant targets of the Trypanosoma cruzi. We found 3H-[1,2]dithioles with the ability to inhibit Trypanosoma cruzi triosephosphate isomerase (TcTIM. Herein, we studied the structural modifications of this chemotype to analyze the influence of volume, lipophilicity and electronic properties in the anti-T. cruzi activity. Their selectivity to parasites vs. mammalian cells was also examined. To get insights into a possible mechanism of action, the inhibition of the enzymatic activity of TcTIM and cruzipain, using the isolated enzymes, and the inhibition of membrane sterol biosynthesis and excreted metabolites, using the whole parasite, were achieved. We found that this structural framework is interesting for the generation of innovative drugs for the treatment of Chagas disease.

  10. Evaluation of the immune response to CRA and FRA recombinant antigens of Trypanosoma cruzi in C57BL/6 mice.

    Science.gov (United States)

    Pereira, Valéria Rêgo Alves; de Lorena, Virginia Maria Barros; Nakazawa, Mineo; da Silva, Ana Paula Galvão; Montarroyos, Ulisses; Correa-Oliveira, Rodrigo; Gomes, Yara de Miranda

    2003-01-01

    Humoral and cellular immune responses were evaluated in 44 C57BL/6 mice immunized with the Trypanosoma cruzi recombinant antigens CRA and FRA. Both antigens induced cutaneous immediate-type hypersensitivity response. The levels of IgG1, IgG2a, IgG2b and IgG3 were high in CRA immunized mice. IgG3 was the predominant isotype. Although no difference in antibody levels was observed in FRA-immunized mice when compared to control mice, both antigens were able to induce lymphoproliferation in immunized mice. Significant differences were observed between incorporation of [ H]- thymidine by spleen cell stimulated in vitro with CRA or FRA and the control group. These results suggest that CRA and FRA could be involved in mechanisms of resistance to Trypanosoma cruzi infection.

  11. Acute Trypanosoma cruzi Infection in Mouse Induces Infertility or Placental Parasite Invasion and Ischemic Necrosis Associated with Massive Fetal Loss

    OpenAIRE

    Mjihdi, Abdelkarim; Lambot, Marie-Alexandra; Stewart, Ian J.; Detournay, Olivier; Noël, Jean-Christophe; Carlier, Yves; Truyens, Carine

    2002-01-01

    Pathogens may impair reproduction in association or not with congenital infections. We have investigated the effect of acute infection with Trypanosoma cruzi, the protozoan agent of Chagas’ disease in Latin America, on reproduction of mice. Although mating of infected mice occurred at a normal rate, 80% of them did not become gravid. In the few gravid infected mice, implantation numbers were as in uninfected control mice, but 28% of fetuses resorbed. Such infertility and early fetal losses we...

  12. Complex I (NADH:ubiquinone oxidoreductase) is active in but non-essential for procyclic Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Verner, Zdeněk; Čermáková, P.; Škodová, Ingrid; Kriegová, Eva; Horváth, A.; Lukeš, Julius

    2011-01-01

    Roč. 175, č. 2 (2011), s. 196-200 ISSN 0166-6851 R&D Projects: GA ČR GA204/09/1667; GA ČR GD206/09/H026; GA MŠk 2B06129; GA MŠk LC07032 Institutional research plan: CEZ:AV0Z60220518 Keywords : Trypanosoma * Mitochondrion * Respiration * Complex I Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.551, year: 2011

  13. Alternative NADH dehydrogenase (NDH2): intermembrane-space-facing counterpart of mitochondrial complex I in the procyclic Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Verner, Zdeněk; Škodová, Ingrid; Poláková, S.; Ďurišová-Benkovičková, V.; Horváth, A.; Lukeš, Julius

    2013-01-01

    Roč. 140, č. 3 (2013), s. 328-337 ISSN 0031-1820 R&D Projects: GA MŠk LC07032; GA ČR GA204/09/1667 Institutional support: RVO:60077344 Keywords : Trypanosoma * mitochondrion * dehydrogenase * respiration * NDH2 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.350, year: 2013 http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=8838254

  14. The assembly of F1FO-ATP synthase is disrupted upon interference of RNA editing in Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Hashimi, Hassan; Benkovičová, V.; Čermáková, P.; Lai, De Hua; Horváth, A.; Lukeš, Julius

    2010-01-01

    Roč. 40, č. 1 (2010), s. 45-54 ISSN 0020-7519 R&D Projects: GA ČR GA204/06/1558; GA AV ČR IAA500960705 Institutional research plan: CEZ:AV0Z60220518 Keywords : RNA editing * ATP synthase * mitochondrion * Trypanosoma * respiratory complex * membrane potential Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.822, year: 2010

  15. Dynamics of Mitochondrial RNA-Binding Protein Complex in Trypanosoma brucei and Its Petite Mutant under Optimized Immobilization Conditions

    Czech Academy of Sciences Publication Activity Database

    Huang, Zhenqiu; Kaltenbrunner, S.; Šimková, Eva; Staněk, David; Lukeš, Julius; Hashimi, Hassan

    2014-01-01

    Roč. 13, č. 9 (2014), s. 1232-1240 ISSN 1535-9778 R&D Projects: GA ČR GAP305/12/2261; GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 ; RVO:68378050 Keywords : mitochondrion * Trypanosoma brucei * YFP Subject RIV: EB - Genetics ; Molecular Biology; EB - Genetics ; Molecular Biology (UMG-J) Impact factor: 2.820, year: 2014

  16. Mitochondrial localization of human frataxin is necessary but processing is not for rescuing frataxin deficiency in Trypanosoma brucei

    Czech Academy of Sciences Publication Activity Database

    Long, Shaojun; Jirků, Milan; Ayala, F. J.; Lukeš, Julius

    2008-01-01

    Roč. 105, č. 36 (2008), s. 13468-13473 ISSN 0027-8424 R&D Projects: GA AV ČR IAA500960705; GA MŠk LC07032; GA MŠk 2B06129; GA ČR GA204/06/1558 Institutional research plan: CEZ:AV0Z60220518 Keywords : frataxin * mitochondrion * Trypanosoma * Kinetoplastida Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 9.380, year: 2008

  17. Hosts and vectors of Trypanosoma cruzi discrete typing units in the Chagas disease endemic region of the Paraguayan Chaco

    OpenAIRE

    ACOSTA, NIDIA; L?PEZ, ELSA; LEWIS, MICHAEL D.; LLEWELLYN, MARTIN S.; G?MEZ, ANA; ROM?N, FABIOLA; MILES, MICHAEL A.; YEO, MATTHEW

    2017-01-01

    SUMMARY Active Trypanosoma cruzi transmission persists in the Gran Chaco region, which is considered hyperendemic for Chagas disease. Understanding domestic and sylvatic transmission cycles and therefore the relationship between vectors and mammalian hosts is crucial to designing and implementing improved effective control strategies. Here we describe the species of triatomine vectors and the sylvatic mammal reservoirs of T. cruzi, in different localities of the Paraguayan and Bolivian Chaco....

  18. Prevalence of antibodies against Trypanosoma cruzi in pregnant women in endemic areas of the department of Boyacá, Colombia

    Directory of Open Access Journals (Sweden)

    Suescún-Carrero, Sandra Helena

    2017-10-01

    Full Text Available Objective: To determine the prevalence of antibodies against Trypanosoma cruzi in pregnant women in endemic areas of Boyacá, Colombia, in 2012 and 2013. Materials and methods: Cross-sectional study of 566 pregnant women from endemic municipalities of Boyacá. Samples were analyzed by means of serological tests for Chagas, namely: IgG ELISA, indirect immunofluorescence and indirect hemagglutination. Cases with positive results in two tests were considered as confirmed. Results: The overall prevalence of antibodies against Trypanosoma cruzi was 2.5 % (14/566. Municipalities with the highest prevalence were Chitaraque (8.3 %, and Soatá (3.3 %. Average age of positive women was 32.6 years, and their gestational period, 18.1 weeks. We found a statistically significant association between age and the presence of antibodies against Trypanosoma cruzi. Conclusion: Prevalence of antibodies against T. cruzi in pregnant women demonstrates the importance of the monitoring program for Chagas disease in pregnancy, as a method for congenital disease control.

  19. Aspectos nutricionais associados à infecção crônica pelo Trypanosoma cruzi (Chagas 1909 entre idosos: Projeto Bambuí Aspectos nutricionales asociados a la infección crónica por el Trypanosoma cruzi (Chagas 1909 entre ancianos: Proyecto Bambuí Nutritional aspects associated with chronic Trypanosoma cruzi (Chagas 1909 infection among older adults: Bambuí Project

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Lima-Costa

    2013-06-01

    Full Text Available O objetivo do estudo foi verificar os aspectos nutricionais associados à infecção crônica pelo Trypanosoma cruzi entre os participantes da linha de base da coorte de idosos de Bambuí, Minas Gerais, Brasil. A análise incluiu 84,9% (1.479 de todos os residentes com 60 anos ou mais na cidade em 1997. A infecção pelo Tr. cruzi foi avaliada por três testes sorológicos e o perfil nutricional foi caracterizado por variáveis antropométricas e bioquímicas. As associações foram avaliadas pelas razões de prevalência e intervalos de 95% de confiança, utilizando a regressão de Poisson robusta e ajustando por potenciais fatores de confusão. A infecção foi observada em 38,1% dos idosos. Todas as variáveis antropométricas apresentaram associação significativa com a infecção, evidenciando menores valores entre os idosos com sorologia positiva. As variáveis bioquímicas não foram associadas ao evento estudado. Os resultados evidenciaram a concomitância da doença de Chagas crônica e pior estado nutricional nessa população, reforçando a importância da avaliação nutricional entre idosos com infecção crônica pelo Tr. cruzi.El objetivo del estudio fue verificar los aspectos nutricionales asociados a la infección crónica por el Trypanosoma cruzi entre los participantes de la línea de base de una cohorte de ancianos de Bambuí, Minas Gerais, Brasil. El análisis incluyó al 84,9% (1.479 de todos los residentes con 60 años o más en la ciudad en 1997. La infección por el Tr. cruzi fue evaluada por tres testes serológicos y el perfil nutricional se caracterizó por variables antropométricas y bioquímicas. Las asociaciones se evaluaron por las razones de prevalencia e intervalos de un 95% de confianza, utilizando la regresión de Poisson robusta y ajustada por potenciales factores de confusión. La infección se observó en un 38,1% de los ancianos. Todas las variables antropométricas presentaron una asociaci

  20. Dermatoses em renais cronicos em terapia dialitica

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    Luis Alberto Batista Peres

    2014-03-01

    Full Text Available Objetivo: As desordens cutâneas e das mucosas são comuns em pacientes em hemodiálise a longo prazo. A diálise prolonga a expectativa de vida, dando tempo para a manifestação destas anormalidades. Os objetivos deste estudo foram avaliar a prevalência de problemas dermatológicos em pacientes com doença renal crônica (DRC em hemodiálise. Métodos: Cento e quarenta e cinco pacientes com doença renal crônica em hemodiálise foram estudados. Todos os pacientes foram completamente analisados para as alterações cutâneas, de cabelos, mucosas e unhas por um único examinador e foram coletados dados de exames laboratoriais. Os dados foram armazenados em um banco de dados do Microsolft Excel e analisados por estatística descritiva. As variáveis contínuas foram comparadas pelo teste t de Student e as variáveis categóricas utilizando o teste do qui-quadrado ou o teste Exato de Fischer, conforme adequado. Resultados: O estudo incluiu 145 pacientes, com idade média de 53,6 ± 14,7 anos, predominantemente do sexo masculino (64,1% e caucasianos (90,0%. O tempo médio de diálise foi de 43,3 ± 42,3 meses. As principais doenças subjacentes foram: hipertensão arterial em 33,8%, diabetes mellitus em 29,6% e glomerulonefrite crônica em 13,1%. As principais manifestações dermatológicas observadas foram: xerose em 109 (75,2%, equimose em 87 (60,0%, prurido em 78 (53,8% e lentigo em 33 (22,8% pacientes. Conclusão: O nosso estudo mostrou a presença de mais do que uma dermatose por paciente. As alterações cutâneas são frequentes em pacientes em diálise. Mais estudos são necessários para melhor caracterização e manejo destas dermatoses.

  1. Contribución al conocimiento de los reservorios del Trypanosoma cruzi (Chagas,1909 en la Provincia de Corrientes, Argentina Contribution to knowledge of reservoirs of Trypanosoma cruzi (Chagas, 1909 in Corrientes Province, Argentina

    Directory of Open Access Journals (Sweden)

    María Esther Bar

    1999-06-01

    Full Text Available Con el propósito de identificar a reservorios del Trypanosoma cruzi se investigaron 60 mamíferos en los Departamentos Capital y San Luis del Palmar. Se examinaron: primates, roedores, marsupiales, carnívoros y edentados; 40 vivían en cautiverio y 20 fueron capturados mediante trampas en una comunidad rural forestal. Los mamíferos fueron analizados por xenodiagnóstico, empleándose ninfas de 3o o 4o estadío de Triatoma infestans ayunadas durante 2 semanas. Las heces de los triatominos fueron observadas al microscopio (400x a los 30, 60 y 90 días post-alimentación. En 2 Saimiri sciureus y en 1 Cebus apella se constató infección por tripanosomas cruziformes. Se concluye que la parasitemia detectada fue baja. La presencia de Didelphis albiventris, reservorio potencial del Trypanosoma cruzi , en una zona de transmisión activa del parásito representa un factor de riesgo, por lo que son necesarias futuras investigaciones epidemiológicas para determinar la real diagnosis de esta parasitosis en la provincia de Corrientes, Argentina.In order to identify Trypanosoma cruzi reservoirs in transmission areas, 60 mammals in Capital and San Luis del Palmar Departments, Corrientes, Argentina were studied. Primates, rodents, carnivores, marsupials and edentates were investigated, 40 of them living in captivity and 20 caught with traps in a rural area. The mammals were examined by xenodiagnosis and third or fourth instars nymphs of Triatoma infestans starved for 2 weeks were used. The feces were microscopically observed (400x for Trypanosoma cruzi infection at 30, 60 and 90 days after feeding. Trypanosoma cruzi-like parasites were identified in 2 Saimiri sciureus and 1 Cebus apella analyzed by xenodiagnosis. It was concluded that parasitemia was low. Howewer, the presence in a forest area of Didelphis albiventris, potential reservoir of the parasite, indicates a risk factor and deserves further epidemiological study for a true diagnosis of this

  2. Reseña Histórica de algunos estudios Colombianos sobre Trypanosoma rangeli

    Directory of Open Access Journals (Sweden)

    Hernando Groot Liévano

    2000-08-01

    Full Text Available

    Parecerá extraño que uno de los primeros artículos de esta revista no se refiera a la enfermedad de Chagas. Tanto es así que cuando el doctor Felipe Guhl tuvo la idea de llamarme para esta presentación, mi primera respuesta fue negativa porque, obviamente debería hablarse del Trypanosoma cruzi y no del Trypanosoma rangeli. El presente artículo es un breve recuento de mi experiencia con este parásito y su importancia dado que coexiste con el T. cruzi y que, en ocasiones la diferenciación morfológica entre los dos no es tan clara cuando se examinan preparaciones de sangre en “gota gruesa” de vertebrados o preparaciones del contenido intestinal de los insectos vectores, y además porque tiene ciertas relaciones inmunológicas que es necesario tener en cuenta para evitar posibles confusiones. Por otra parte, su distribución geográfica es muy amplia extendiéndose desde México hasta el Perú y el Brasil.

    El Trypanosoma rangeli, llamado así por un distinguido médico y posteriormente diplomático de Venezuela, el doctor Enrique Tejera, quien encontró en los chipos, o sea en los Rhodnius prolixus de Venezuela, un pequeño flagelado muy largo, bastante diferente del Trypanosoma cruzi y resolvió ponerle el nombre de Trypanosoma o Crithidia rangeli pues no estaba muy seguro del género en el cual debía colocarlo. Evidentemente, sólo había visto la morfología de estos flagelados en el intestino de los Rhodnius y por consiguiente no tenía ningún otro elemento para identi-ficarlos.

    Únicamente comprobó que eran diferentes del cruzi. ¿Por qué le dedicó su descubrimiento a Rangel? Creo que es importante que nosotros los latinoamericanos conozcamos bien los valores científicos que han habido en nuestros países y en vez de preocuparnos por las artificiales fronteras políticas, lo cual en nada contribuye al progreso de la ciencia, comencemos a tener claro conocimiento de lo que en todas estas naciones hermanas por

  3. Experiências sôbre a transmissão do Trypanosoma cruzi por sanguessugas e de tripanosomas de vertebrados de sangue frio por triatomíneos Experiments of the transmission of Trypanosoma cruzi by leechs and cold blooded vertebrate trypanosomas by triatominae

    Directory of Open Access Journals (Sweden)

    Samuel B. Pessôa

    1969-06-01

    Full Text Available Observou-se que o Trypanosoma cruzi não se multiplica na sanguessuga (Haementeria lutzi Pinto; os tripanosomas sugados degeneram após algum tempo; outros permanecem aparentemente normais, porém 48 horas após a ingestão infectante acabam morrendo. Observou-se ainda que os tripanosomas parasitas da rã (T. rotatorium e T. leptodactyli bem como o T. hogei, parasita da serpente Rachidelus brazili, não se multiplicam no intestino dos triatomíneos. O mais resistente (o T. leptodactyli, permanece vivo até 72 horas após a ingestão infectante, porém as outras duas espécies (T. rotatorium e T. hogei não resistem mais de 24 horas após serem sugadas pelos triatomíneos.Trypanosoma cruzi does not reproduce itself in the leech (Haementerm lutzi Pinto; the ingested trypanosomes degenerate after some time; other organisms remain apparently normal, however dying 48 hours after the feeding of the leechs. The parasite trypanosomas of the frog (T. rotatorium and T. leptodactyli as well as those parasiting the ophidian Rachidelus brazili (T. hogei do not multiply in the intestine of the triatominae. The most resistent species (T. leptocbactyli remains alive 72 hours after the feeding of the triatominae; the other two, however, do not survive more than 24 hours.

  4. Increased genetic diversity and prevalence of co-infection with Trypanosoma spp. in koalas (Phascolarctos cinereus and their ticks identified using next-generation sequencing (NGS.

    Directory of Open Access Journals (Sweden)

    Amanda D Barbosa

    Full Text Available Infections with Trypanosoma spp. have been associated with poor health and decreased survival of koalas (Phascolarctos cinereus, particularly in the presence of concurrent pathogens such as Chlamydia and koala retrovirus. The present study describes the application of a next-generation sequencing (NGS-based assay to characterise the prevalence and genetic diversity of trypanosome communities in koalas and two native species of ticks (Ixodes holocyclus and I. tasmani removed from koala hosts. Among 168 koalas tested, 32.2% (95% CI: 25.2-39.8% were positive for at least one Trypanosoma sp. Previously described Trypanosoma spp. from koalas were identified, including T. irwini (32.1%, 95% CI: 25.2-39.8%, T. gilletti (25%, 95% CI: 18.7-32.3%, T. copemani (27.4%, 95% CI: 20.8-34.8% and T. vegrandis (10.1%, 95% CI: 6.0-15.7%. Trypanosoma noyesi was detected for the first time in koalas, although at a low prevalence (0.6% 95% CI: 0-3.3%, and a novel species (Trypanosoma sp. AB-2017 was identified at a prevalence of 4.8% (95% CI: 2.1-9.2%. Mixed infections with up to five species were present in 27.4% (95% CI: 21-35% of the koalas, which was significantly higher than the prevalence of single infections 4.8% (95% CI: 2-9%. Overall, a considerably higher proportion (79.7% of the Trypanosoma sequences isolated from koala blood samples were identified as T. irwini, suggesting this is the dominant species. Co-infections involving T. gilletti, T. irwini, T. copemani, T. vegrandis and Trypanosoma sp. AB-2017 were also detected in ticks, with T. gilletti and T. copemani being the dominant species within the invertebrate hosts. Direct Sanger sequencing of Trypanosoma 18S rRNA gene amplicons was also performed and results revealed that this method was only able to identify the genotypes with greater amount of reads (according to NGS within koala samples, which highlights the advantages of NGS in detecting mixed infections. The present study provides new insights

  5. Increased genetic diversity and prevalence of co-infection with Trypanosoma spp. in koalas (Phascolarctos cinereus) and their ticks identified using next-generation sequencing (NGS).

    Science.gov (United States)

    Barbosa, Amanda D; Gofton, Alexander W; Paparini, Andrea; Codello, Annachiara; Greay, Telleasha; Gillett, Amber; Warren, Kristin; Irwin, Peter; Ryan, Una

    2017-01-01

    Infections with Trypanosoma spp. have been associated with poor health and decreased survival of koalas (Phascolarctos cinereus), particularly in the presence of concurrent pathogens such as Chlamydia and koala retrovirus. The present study describes the application of a next-generation sequencing (NGS)-based assay to characterise the prevalence and genetic diversity of trypanosome communities in koalas and two native species of ticks (Ixodes holocyclus and I. tasmani) removed from koala hosts. Among 168 koalas tested, 32.2% (95% CI: 25.2-39.8%) were positive for at least one Trypanosoma sp. Previously described Trypanosoma spp. from koalas were identified, including T. irwini (32.1%, 95% CI: 25.2-39.8%), T. gilletti (25%, 95% CI: 18.7-32.3%), T. copemani (27.4%, 95% CI: 20.8-34.8%) and T. vegrandis (10.1%, 95% CI: 6.0-15.7%). Trypanosoma noyesi was detected for the first time in koalas, although at a low prevalence (0.6% 95% CI: 0-3.3%), and a novel species (Trypanosoma sp. AB-2017) was identified at a prevalence of 4.8% (95% CI: 2.1-9.2%). Mixed infections with up to five species were present in 27.4% (95% CI: 21-35%) of the koalas, which was significantly higher than the prevalence of single infections 4.8% (95% CI: 2-9%). Overall, a considerably higher proportion (79.7%) of the Trypanosoma sequences isolated from koala blood samples were identified as T. irwini, suggesting this is the dominant species. Co-infections involving T. gilletti, T. irwini, T. copemani, T. vegrandis and Trypanosoma sp. AB-2017 were also detected in ticks, with T. gilletti and T. copemani being the dominant species within the invertebrate hosts. Direct Sanger sequencing of Trypanosoma 18S rRNA gene amplicons was also performed and results revealed that this method was only able to identify the genotypes with greater amount of reads (according to NGS) within koala samples, which highlights the advantages of NGS in detecting mixed infections. The present study provides new insights on the

  6. Trypanosoma cruzi in dogs: electrocardiographic and echocardiographic evaluation, in Malinalco, State of Mexico

    Directory of Open Access Journals (Sweden)

    González-Vieyra SD

    2011-12-01

    Full Text Available Sandra Díaz González-Vieyra1, Ninfa Ramírez-Durán2, Ángel H Sandoval-Trujillo3, Juan C Vázquez-Chagoyán1, Humberto G Monroy-Salazar1, Alberto Barbabosa-Pliego11Research Center of Advanced Studies in Animal Health, Veterinary Husbandry School, 2Medical and Ambiental Microbiology, Research Center of Advanced Studies in Health Science, School of Medicine, Autonomous University of the State of Mexico, Toluca, Mexico; 3Department of Biological Systems, Metropolitan Autonomous University, Xochimilco, Mexico City, MexicoAbstract: Chagas disease caused by Trypanosoma cruzi is an important public health problem in Latin America. Dogs are considered a risk factor for human Chagas disease, a sentinel for T. cruzi infection in endemic regions and an animal model to study pathological aspects of the disease. The potential use of dogs as indicators of human cardiac pathogenicity of local T. cruzi strains has been studied insufficiently. We studied electrocardiographic (EKG and echocardiographic (ECG alteration frequencies observed in an open population of dogs in Malinalco, Mexico, and determined if such frequencies were statistically associated with T. cruzi infection in dogs. Animals (n = 139 were clinically examined and owners were asked to answer a questionnaire about dogs’ living conditions. Two commercial serological tests (IHA, ELISA were conducted to detect anti-T. cruzi serum antibodies. Significant differences between seropositive and seronegative animals in cardiomyopathic frequencies were detected through EKG and ECG (P < 0.05. Thirty dogs (21.58% were serologically positive to anti-T. cruzi antibodies (to ELISA and IHA assays, of which nine (30% had EKG and/or ECG alterations. From the remaining 104 (78.42% seronegative animals, five (4.5% had EKG and/or ECG abnormalities. Our data support the hypothesis that most EKG and ECG alterations found in dogs from Malinalco could be associated with T. cruzi infection. Considering the dog as a

  7. Distantiae transmission of Trypanosoma cruzi: a new epidemiological feature of acute Chagas disease in Brazil.

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    Samanta Cristina das Chagas Xavier

    2014-05-01

    Full Text Available BACKGROUND: The new epidemiological scenario of orally transmitted Chagas disease that has emerged in Brazil, and mainly in the Amazon region, needs to be addressed with a new and systematic focus. Belém, the capital of Pará state, reports the highest number of acute Chagas disease (ACD cases associated with the consumption of açaí juice. METHODOLOGY/PRINCIPAL FINDINGS: The wild and domestic enzootic transmission cycles of Trypanosoma cruzi were evaluated in the two locations (Jurunas and Val-de Cães that report the majority of the autochthonous cases of ACD in Belém city. Moreover, we evaluated the enzootic cycle on the three islands that provide most of the açaí fruit that is consumed in these localities. We employed parasitological and serological tests throughout to evaluate infectivity competence and exposure to T. cruzi. In Val-de-Cães, no wild mammal presented positive parasitological tests, and 56% seroprevalence was observed, with low serological titers. Three of 14 triatomines were found to be infected (TcI. This unexpected epidemiological picture does not explain the high number of autochthonous ACD cases. In Jurunas, the cases of ACD could not be autochthonous because of the absence of any enzootic cycle of T. cruzi. In contrast, in the 3 island areas from which the açaí fruit originates, 66.7% of wild mammals and two dogs displayed positive hemocultures, and 15.6% of triatomines were found to be infected by T. cruzi. Genotyping by mini-exon gene and PCR-RFLP (1f8/Akw21I targeting revealed that the mammals and triatomines from the islands harbored TcI and Trypanosoma rangeli in single and mixed infections. CONCLUSION/SIGNIFICANCE: These findings show that cases of Chagas disease in the urban area of Belém may be derived from infected triatomines coming together with the açaí fruits from distant islands. We term this new epidemiological feature of Chagas disease as "Distantiae transmission".

  8. Trypanocide Treatment of Women Infected with Trypanosoma cruzi and Its Effect on Preventing Congenital Chagas

    Science.gov (United States)

    Fabbro, Diana L.; Danesi, Emmaria; Olivera, Veronica; Codebó, Maria Olenka; Denner, Susana; Heredia, Cecilia; Streiger, Mirtha; Sosa-Estani, Sergio

    2014-01-01

    With the control of the vectorial and transfusional routes of infection with Trypanosoma cruzi, congenital transmission has become an important source of new cases. This study evaluated the efficacy of trypanocidal therapy to prevent congenital Chagas disease and compared the clinical and serological evolution between treated and untreated infected mothers. We conducted a multicenter, observational study on a cohort of mothers infected with T. cruzi, with and without trypanocidal treatment before pregnancy. Their children were studied to detect congenital infection. Among 354 “chronically infected mother-biological child” pairs, 132 were treated women and 222 were untreated women. Among the children born to untreated women, we detected 34 infected with T. cruzi (15.3%), whose only antecedent was maternal infection. Among the 132 children of previously treated women, no infection with T. cruzi was found (0.0%) (p<0.05). Among 117 mothers with clinical and serological follow up, 71 had been treated and 46 were untreated. The women were grouped into three groups. Group A: 25 treated before 15 years of age; Group B: 46 treated at 15 or more years of age; Group C: untreated, average age of 29.2±6.2 years at study entry. Follow-up for Groups A, B and C was 16.3±5.8, 17.5±9.2 and 18.6±8.6 years respectively. Negative seroconversion: Group A, 64.0% (16/25); Group B, 32.6% (15/46); Group C, no seronegativity was observed. Clinical electrocardiographic alterations compatible with chagasic cardiomyopathy: Group A 0.0% (0/25); B 2.2% (1/46) and C 15.2% (7/46). The trypanocidal treatment of women with chronic Chagas infection was effective in preventing the congenital transmission of Trypanosoma cruzi to their children; it had also a protective effect on the women's clinical evolution and deparasitation could be demonstrated in many treated women after over 10 years of follow up. PMID:25411847

  9. Channel-forming activities in the glycosomal fraction from the bloodstream form of Trypanosoma brucei.

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    Melisa Gualdron-López

    Full Text Available BACKGROUND: Glycosomes are a specialized form of peroxisomes (microbodies present in unicellular eukaryotes that belong to the Kinetoplastea order, such as Trypanosoma and Leishmania species, parasitic protists causing severe diseases of livestock and humans in subtropical and tropical countries. The organelles harbour most enzymes of the glycolytic pathway that is responsible for substrate-level ATP production in the cell. Glycolysis is essential for bloodstream-form Trypanosoma brucei and enzymes comprising this pathway have been validated as drug targets. Glycosomes are surrounded by a single membrane. How glycolytic metabolites are transported across the glycosomal membrane is unclear. METHODS/PRINCIPAL FINDINGS: We hypothesized that glycosomal membrane, similarly to membranes of yeast and mammalian peroxisomes, contains channel-forming proteins involved in the selective transfer of metabolites. To verify this prediction, we isolated a glycosomal fraction from bloodstream-form T. brucei and reconstituted solubilized membrane proteins into planar lipid bilayers. The electrophysiological characteristics of the channels were studied using multiple channel recording and single channel analysis. Three main channel-forming activities were detected with current amplitudes 70-80 pA, 20-25 pA, and 8-11 pA, respectively (holding potential +10 mV and 3.0 M KCl as an electrolyte. All channels were in fully open state in a range of voltages ±150 mV and showed no sub-conductance transitions. The channel with current amplitude 20-25 pA is anion-selective (P(K+/P(Cl-∼0.31, while the other two types of channels are slightly selective for cations (P(K+/P(Cl- ratios ∼1.15 and ∼1.27 for the high- and low-conductance channels, respectively. The anion-selective channel showed an intrinsic current rectification that may suggest a functional asymmetry of the channel's pore. CONCLUSIONS/SIGNIFICANCE: These results indicate that the membrane of glycosomes

  10. Trypanocide treatment of women infected with Trypanosoma cruzi and its effect on preventing congenital Chagas.

    Science.gov (United States)

    Fabbro, Diana L; Danesi, Emmaria; Olivera, Veronica; Codebó, Maria Olenka; Denner, Susana; Heredia, Cecilia; Streiger, Mirtha; Sosa-Estani, Sergio

    2014-11-01

    With the control of the vectorial and transfusional routes of infection with Trypanosoma cruzi, congenital transmission has become an important source of new cases. This study evaluated the efficacy of trypanocidal therapy to prevent congenital Chagas disease and compared the clinical and serological evolution between treated and untreated infected mothers. We conducted a multicenter, observational study on a cohort of mothers infected with T. cruzi, with and without trypanocidal treatment before pregnancy. Their children were studied to detect congenital infection. Among 354 "chronically infected mother-biological child" pairs, 132 were treated women and 222 were untreated women. Among the children born to untreated women, we detected 34 infected with T. cruzi (15.3%), whose only antecedent was maternal infection. Among the 132 children of previously treated women, no infection with T. cruzi was found (0.0%) (p<0.05). Among 117 mothers with clinical and serological follow up, 71 had been treated and 46 were untreated. The women were grouped into three groups. Group A: 25 treated before 15 years of age; Group B: 46 treated at 15 or more years of age; Group C: untreated, average age of 29.2 ± 6.2 years at study entry. Follow-up for Groups A, B and C was 16.3 ± 5.8, 17.5 ± 9.2 and 18.6 ± 8.6 years respectively. Negative seroconversion: Group A, 64.0% (16/25); Group B, 32.6% (15/46); Group C, no seronegativity was observed. Clinical electrocardiographic alterations compatible with chagasic cardiomyopathy: Group A 0.0% (0/25); B 2.2% (1/46) and C 15.2% (7/46). The trypanocidal treatment of women with chronic Chagas infection was effective in preventing the congenital transmission of Trypanosoma cruzi to their children; it had also a protective effect on the women's clinical evolution and deparasitation could be demonstrated in many treated women after over 10 years of follow up.

  11. Diminazene aceturate (Berenil modulates the host cellular and inflammatory responses to Trypanosoma congolense infection.

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    Shiby Kuriakose

    Full Text Available BACKGROUND: Trypanosoma congolense are extracellular and intravascular blood parasites that cause debilitating acute or chronic disease in cattle and other domestic animals. Diminazene aceturate (Berenil has been widely used as a chemotherapeutic agent for trypanosomiasis in livestock since 1955. As in livestock, treatment of infected highly susceptible BALB/c mice with Berenil leads to rapid control of parasitemia and survival from an otherwise lethal infection. The molecular and biochemical mechanisms of action of Berenil are still not very well defined and its effect on the host immune system has remained relatively unstudied. Here, we investigated whether Berenil has, in addition to its trypanolytic effect, a modulatory effect on the host immune response to Trypanosoma congolense. METHODOLOGY/PRINCIPAL FINDINGS: BALB/c and C57BL/6 mice were infected intraperitoneally with T. congolense, treated with Berenil and the expression of CD25 and FoxP3 on splenic cells was assessed directly ex vivo. In addition, serum levels and spontaneous and LPS-induced production of pro-inflammatory cytokines by splenic and hepatic CD11b⁺ cells were determined by ELISA. Berenil treatment significantly reduced the percentages of CD25⁺ cells, a concomitant reduction in the percentage of regulatory (CD4⁺Foxp3⁺ T cells and a striking reduction in serum levels of disease exacerbating pro-inflammatory cytokines including IL-6, IL-12, TNF and IFN-γ. Furthermore, Berenil treatment significantly suppressed spontaneous and LPS-induced production of inflammatory cytokines by splenic and liver macrophages and significantly ameliorated LPS-induced septic shock and the associated cytokine storm. CONCLUSIONS/SIGNIFICANCE: Collectively, these results provide evidence that in addition to its direct trypanolytic effect, Berenil also modulates the host immune response to the parasite in a manner that dampen excessive immune activation and production of pathology

  12. Triatominae-Trypanosoma cruzi/T. rangeli: Vector-parasite interactions.

    Science.gov (United States)

    Vallejo, G A; Guhl, F; Schaub, G A

    2009-01-01

    Of the currently known 140 species in the family Reduviidae, subfamily Triatominae, those which are most important as vectors of the aetiologic agent of Chagas disease, Trypanosoma cruzi, belong to the tribes Triatomini and Rhodniini. The latter not only transmit T. cruzi but also Trypanosoma rangeli, which is considered apathogenic for the mammalian host but can be pathogenic for the vectors. Using different molecular methods, two main lineages of T. cruzi have been classified, T. cruzi I and T. cruzi II. Within T. cruzi II, five subdivisions are recognized, T. cruzi IIa-IIe, according to the variability of the ribosomal subunits 24Salpha rRNA and 18S rRNA. In T. rangeli, differences in the organization of the kinetoplast DNA separate two forms denoted T. rangeli KP1+ and KP1-, although differences in the intergenic mini-exon gene and of the small subunit rRNA (SSU rRNA) suggest four subpopulations denoted T. rangeli A, B, C and D. The interactions of these subpopulations of the trypanosomes with different species and populations of Triatominae determine the epidemiology of the human-infecting trypanosomes in Latin America. Often, specific subpopulations of the trypanosomes are transmitted by specific vectors in a particular geographic area. Studies centered on trypanosome-triatomine interaction may allow identification of co-evolutionary processes, which, in turn, could consolidate hypotheses of the evolution and the distribution of T. cruzi/T. rangeli-vectors in America, and they may help to identify the mechanisms that either facilitate or impede the transmission of the parasites in different vector species. Such mechanisms seem to involve intestinal bacteria, especially the symbionts which are needed by the triatomines to complete nymphal development and to produce eggs. Development of the symbionts is regulated by the vector. T. cruzi and T. rangeli interfere with this system and induce the production of antibacterial substances. Whereas T. cruzi is only

  13. EM International. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-01

    It is the intent of EM International to describe the Office of Environmental Restoration and Waste Management`s (EM`s) various roles and responsibilities within the international community. Cooperative agreements and programs, descriptions of projects and technologies, and synopses of visits to international sites are all highlighted in this semiannual journal. Focus on EM programs in this issue is on international collaboration in vitrification projects. Technology highlights covers: in situ sealing for contaminated sites; and remote sensors for toxic pollutants. Section on profiles of countries includes: Arctic contamination by the former Soviet Union, and EM activities with Germany--cooperative arrangements.

  14. Trypanosoma cruzi Evades the Complement System as an Efficient Strategy to Survive in the Mammalian Host: The Specific Roles of Host/Parasite Molecules and Trypanosoma cruzi Calreticulin

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    Galia Ramírez-Toloza

    2017-09-01

    Full Text Available American Trypanosomiasis is an important neglected reemerging tropical parasitism, infecting about 8 million people worldwide. Its agent, Trypanosoma cruzi, exhibits multiple mechanisms to evade the host immune response and infect host cells. An important immune evasion strategy of T. cruzi infective stages is its capacity to inhibit the complement system activation on the parasite surface, avoiding opsonizing, immune stimulating and lytic effects. Epimastigotes, the non-infective form of the parasite, present in triatomine arthropod vectors, are highly susceptible to complement-mediated lysis while trypomastigotes, the infective form, present in host bloodstream, are resistant. Thus T. cruzi susceptibility to complement varies depending on the parasite stage (amastigote, trypomastigotes or epimastigote and on the T. cruzi strain. To avoid complement-mediated lysis, T. cruzi trypomastigotes express on the parasite surface a variety of complement regulatory proteins, such as glycoprotein 58/68 (gp58/68, T. cruzi complement regulatory protein (TcCRP, trypomastigote decay-accelerating factor (T-DAF, C2 receptor inhibitor trispanning (CRIT and T. cruzi calreticulin (TcCRT. Alternatively, or concomitantly, the parasite captures components with complement regulatory activity from the host bloodstream, such as factor H (FH and plasma membrane-derived vesicles (PMVs. All these proteins inhibit different steps of the classical (CP, alternative (AP or lectin pathways (LP. Thus, TcCRP inhibits the CP C3 convertase assembling, gp58/68 inhibits the AP C3 convertase, T-DAF interferes with the CP and AP convertases assembling, TcCRT inhibits the CP and LP, CRIT confers ability to resist the CP and LP, FH is used by trypomastigotes to inhibit the AP convertases and PMVs inhibit the CP and LP C3 convertases. Many of these proteins have similar molecular inhibitory mechanisms. Our laboratory has contributed to elucidate the role of TcCRT in the host

  15. Microsatellite Loci in the Gypsophyte <em>Lepidium subulatum em>(Brassicaceae, and Transferability to Other <em>Lepidieae>

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    José Gabriel Segarra-Moragues

    2012-09-01

    Full Text Available Polymorphic microsatellite markers were developed for the Ibero-North African, strict gypsophyte <em>Lepidium subulatumem> to unravel the effects of habitat fragmentation in levels of genetic diversity, genetic structure and gene flow among its populations. Using 454 pyrosequencing 12 microsatellite loci including di- and tri-nucleotide repeats were characterized in <em>L. subulatumem>. They amplified a total of 80 alleles (2–12 alleles per locus in a sample of 35 individuals of <em>L. subulatumem>, showing relatively high levels of genetic diversity, <em>H>O = 0.645, <em>H>E = 0.627. Cross-species transferability of all 12 loci was successful for the Iberian endemics <em>Lepidium cardaminesem>, <em>Lepidium stylatumem>, and the widespread, <em>Lepidium graminifoliumem> and one species each of two related genera, <em>Cardaria drabaem> and <em>Coronopus didymusem>. These microsatellite primers will be useful to investigate genetic diversity, population structure and to address conservation genetics in species of <em>Lepidium>.

  16. Differential Editosome Protein Function between Life Cycle Stages of Trypanosoma brucei.

    Science.gov (United States)

    McDermott, Suzanne M; Guo, Xuemin; Carnes, Jason; Stuart, Kenneth

    2015-10-09

    Uridine insertion and deletion RNA editing generates functional mitochondrial mRNAs in Trypanosoma brucei. The mRNAs are differentially edited in bloodstream form (BF) and procyclic form (PF) life cycle stages, and this correlates with the differential utilization of glycolysis and oxidative phosphorylation between the stages. The mechanism that controls this differential editing is unknown. Editing is catalyzed by multiprotein ∼20S editosomes that contain endonuclease, 3'-terminal uridylyltransferase, exonuclease, and ligase activities. These editosomes also contain KREPB5 and KREPA3 proteins, which have no functional catalytic motifs, but they are essential for parasite viability, editing, and editosome integrity in BF cells. We show here that repression of KREPB5 or KREPA3 is also lethal in PF, but the effects on editosome structure differ from those in BF. In addition, we found that point mutations in KREPB5 or KREPA3 differentially affect cell growth, editosome integrity, and RNA editing between BF and PF stages. These results indicate that the functions of KREPB5 and KREPA3 editosome proteins are adjusted between the life cycle stages. This implies that these proteins are involved in the processes that control differential editing and that the 20S editosomes differ between the life cycle stages. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Bioenergetic profiling of Trypanosoma cruzi life stages using Seahorse extracellular flux technology.

    Science.gov (United States)

    Shah-Simpson, Sheena; Pereira, Camila F A; Dumoulin, Peter C; Caradonna, Kacey L; Burleigh, Barbara A

    2016-08-01

    Energy metabolism is an attractive target for the development of new therapeutics against protozoan pathogens, including Trypanosoma cruzi, the causative agent of human Chagas disease. Despite emerging evidence that mitochondrial electron transport is essential for the growth of intracellular T. cruzi amastigotes in mammalian cells, fundamental knowledge of mitochondrial energy metabolism in this parasite life stage remains incomplete. The Clark-type electrode, which measures the rate of oxygen consumption, has served as the traditional tool to study mitochondrial energetics and has contributed to our understanding of it in T. cruzi. Here, we evaluate the Seahorse XF(e)24 extracellular flux platform as an alternative method to assess mitochondrial bioenergetics in isolated T. cruzi parasites. We report optimized assay conditions used to perform mitochondrial stress tests with replicative life cycle stages of T. cruzi using the XF(e)24 instrument, and discuss the advantages and potential limitations of this methodology, as applied to T. cruzi and other trypanosomatids. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Isothermal microcalorimetry, a new tool to monitor drug action against Trypanosoma brucei and Plasmodium falciparum.

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    Tanja Wenzler

    Full Text Available Isothermal microcalorimetry is an established tool to measure heat flow of physical, chemical or biological processes. The metabolism of viable cells produces heat, and if sufficient cells are present, their heat production can be assessed by this method. In this study, we investigated the heat flow of two medically important protozoans, Trypanosoma brucei rhodesiense and Plasmodium falciparum. Heat flow signals obtained for these pathogens allowed us to monitor parasite growth on a real-time basis as the signals correlated with the number of viable cells. To showcase the potential of microcalorimetry for measuring drug action on pathogenic organisms, we tested the method with three antitrypanosomal drugs, melarsoprol, suramin and pentamidine and three antiplasmodial drugs, chloroquine, artemether and dihydroartemisinin, each at two concentrations on the respective parasite. With the real time measurement, inhibition was observed immediately by a reduced heat flow compared to that in untreated control samples. The onset of drug action, the degree of inhibition and the time to death of the parasite culture could conveniently be monitored over several days. Microcalorimetry is a valuable element to be added to the toolbox for drug discovery for protozoal diseases such as human African trypanosomiasis and malaria. The method could probably be adapted to other protozoan parasites, especially those growing extracellularly.

  19. Enhancing effects of gamma interferon on phagocytic cell association with and killing of Trypanosoma cruzi

    Science.gov (United States)

    Wirth, J. J.; Kierszenbaum, F.; Sonnenfeld, G.; Zlotnik, A.

    1985-01-01

    Results are reported from a study of the influence gamma interferon (GIFN) and interleukin 2 (IL2) have on the capability of P388D1 cells and mouse resident peritoneal macrophages (MPM) to attach to the blood-resident parasites Trypanosoma cruzi and kill them. Cultures of trypomastigote forms of the Tulahuen strain of T. cruzi grown in bovine serum were introduced into peritoneal cells of mice, along with P388D1 cells incubated with GIFN, IL2 and both. Control cells were also maintained. Statistical analysis were then performed on data on counts of the number of dead T. Cruzi cells. The GIFN enhanced the interaction of MPM and P388D1 cells with the surface of T. Cruzi, provided the interaction was given over 12 hr to take place. A depression of the cytotoxicity of P388D1 cells was attributed to mediation by H2O2, an effect partially offset by incubation with the lymphokine GIFN.

  20. Protein preparation, crystallization and preliminary X-ray analysis of Trypanosoma cruzi nucleoside diphosphate kinase 1

    International Nuclear Information System (INIS)

    Gómez Barroso, J. A.; Pereira, H.; Miranda, M.; Pereira, C.; Garratt, R. C.; Aguilar, C. F.

    2010-01-01

    T. cruzi TcNDPK1 was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. The flagellated protozoan parasite Trypanosoma cruzi is the aetiological agent of Chagas disease. Nucleoside diphosphate kinases (NDPKs) are enzymes that are involved in energy management and nucleoside balance in the cell. T. cruzi TcNDPK1, a canonical isoform, was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. Crystals grew after 72 h in 0.2 M MgCl 2 , 20% PEG 3350. Data were collected to 3.5 Å resolution using synchrotron X-ray radiation at the National Synchrotron Light Laboratory (Campinas, Brazil). The crystals belonged to the trigonal space group P3, with unit-cell parameters a = b = 127.84, c = 275.49 Å. Structure determination is under way and will provide relevant information that may lead to the first step in rational drug design for the treatment of Chagas disease

  1. Differential expression profiles in the midgut of Triatoma infestans infected with Trypanosoma cruzi.

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    Diego S Buarque

    Full Text Available Chagas disease, or American trypanosomiasis, is a parasitic disease caused by the protozoan Trypanosoma cruzi and is transmitted by insects from the Triatominae subfamily. To identify components involved in the protozoan-vector relationship, we constructed and analyzed cDNA libraries from RNA isolated from the midguts of uninfected and T. cruzi-infected Triatoma infestans, which are major vectors of Chagas disease. We generated approximately 440 high-quality Expressed Sequence Tags (ESTs from each T. infestans midgut cDNA library. The sequences were grouped in 380 clusters, representing an average length of 664.78 base pairs (bp. Many clusters were not classified functionally, representing unknown transcripts. Several transcripts involved in different processes (e.g., detoxification showed differential expression in response to T. cruzi infection. Lysozyme, cathepsin D, a nitrophorin-like protein and a putative 14 kDa protein were significantly upregulated upon infection, whereas thioredoxin reductase was downregulated. In addition, we identified several transcripts related to metabolic processes or immunity with unchanged expressions, including infestin, lipocalins and defensins. We also detected ESTs encoding juvenile hormone binding protein (JHBP, which seems to be involved in insect development and could be a target in control strategies for the vector. This work demonstrates differential gene expression upon T. cruzi infection in the midgut of T. infestans. These data expand the current knowledge regarding vector-parasite interactions for Chagas disease.

  2. Usefulness of microsatellite typing in population genetic studies of Trypanosoma cruzi

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    Macedo Andrea M

    2001-01-01

    Full Text Available Through microsatellite analysis of 53 monoclonal populations of Trypanosoma cruzi, we found a remarkable degree of genetic polymorphism with no single multilocus genotype being observed more than once. The microsatellite profile proved to be stable during 70 generations of the CL Brener clone in culture. The microsatellite profiling presented also high diagnostic sensitivity since DNA amplifications could be achieved with less than 100 fg DNA, corresponding to half parasite total DNA content. Based on these technical attributes the microsatellite assay turns out to be an important tool for direct typing T. cruzi in biological samples. By using this approach we were able to type T. cruzi in feces of artificially infected bugs and in single cells sorted by FACS. The microsatellites have shown to be excellent markers for T. cruzi phylogenetic reconstruction. We used maximum parsimony based on the minimum number of mutational steps to build an unrooted Wagner network, which confirms previous conclusions based on the analysis of the D7 domain of the LSU rDNA gene that T. cruzi is composed by two major groups. We also obtained evidence that strains belonging to rRNA group 2 are subdivided into two genetically distant clusters, and that one of these clusters is more related to rRNA group 1/2. These results suggest different origins for these strains.

  3. Trypanosoma cruzi strains from triatomine collected in Bahia and Rio Grande do Sul, Brazil

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    Aline Rimoldi Ribeiro

    2014-04-01

    Full Text Available OBJECTIVE Collection of triatomines in domestic, peridomestic and sylvatic environments in states of Bahia and Rio Grande do Sul, Northeastern and Southern Brazil respectively, and isolation of Trypanosoma cruzi strains. METHODS First, the captured triatomines were identified using insect identification keys, then their intestinal content was examined by abdominal compression, and the samples containing trypanosomatid forms were inoculated in LIT medium and Swiss mice. RESULTS Six triatomine species were collected in cities in Bahia, namely Panstrongylus geniculatus (01, Triatoma melanocephala (11, T. lenti (94, T. pseudomaculata (02, T. sherlocki (26 and T. sordida (460, and two in cities in Rio Grande do Sul, namely T. circummaculata (11 and T. rubrovaria (115. Out of the specimens examined, T. cruzi was isolated from 28 triatomine divided into four different species: T. melanocephala (one, T. lenti (one, T. rubrovaria (16 and T. sordida (10. Their index of natural infection by T. cruzi was 6.4%. CONCLUSIONS The isolation of T. cruzi strains from triatomines found in domestic and peridomestic areas shows the potential risk of transmission of Chagas disease in the studied cities. The maintenance of those T. cruzi strains in laboratory is intended to promote studies that facilitate the understanding of the parasite-vector-host relationship.

  4. Benznidazole biotransformation and multiple targets in Trypanosoma cruzi revealed by metabolomics.

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    Andrea Trochine

    2014-05-01

    Full Text Available The first line treatment for Chagas disease, a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi, involves administration of benznidazole (Bzn. Bzn is a 2-nitroimidazole pro-drug which requires nitroreduction to become active, although its mode of action is not fully understood. In the present work we used a non-targeted MS-based metabolomics approach to study the metabolic response of T. cruzi to Bzn.Parasites treated with Bzn were minimally altered compared to untreated trypanosomes, although the redox active thiols trypanothione, homotrypanothione and cysteine were significantly diminished in abundance post-treatment. In addition, multiple Bzn-derived metabolites were detected after treatment. These metabolites included reduction products, fragments and covalent adducts of reduced Bzn linked to each of the major low molecular weight thiols: trypanothione, glutathione, γ-glutamylcysteine, glutathionylspermidine, cysteine and ovothiol A. Bzn products known to be generated in vitro by the unusual trypanosomal nitroreductase, TcNTRI, were found within the parasites, but low molecular weight adducts of glyoxal, a proposed toxic end-product of NTRI Bzn metabolism, were not detected.Our data is indicative of a major role of the thiol binding capacity of Bzn reduction products in the mechanism of Bzn toxicity against T. cruzi.

  5. Structure of a Trypanosoma brucei α/β-hydrolase fold protein with unknown function

    International Nuclear Information System (INIS)

    Merritt, Ethan A.; Holmes, Margaret; Buckner, Frederick S.; Van Voorhis, Wesley C.; Quartly, Erin; Phizicky, Eric M.; Lauricella, Angela; Luft, Joseph; DeTitta, George; Neely, Helen; Zucker, Frank; Hol, Wim G. J.

    2008-01-01

    T. brucei gene Tb10.6k15.0140 codes for an α/β-hydrolase fold protein of unknown function. The 2.2 Å crystal structure shows that members of this sequence family retain a conserved Ser residue at the expected site of a catalytic nucleophile, but that trypanosomatid sequences lack structural homologs for the other expected residues of the catalytic triad. The structure of a structural genomics target protein, Tbru020260AAA from Trypanosoma brucei, has been determined to a resolution of 2.2 Å using multiple-wavelength anomalous diffraction at the Se K edge. This protein belongs to Pfam sequence family PF08538 and is only distantly related to previously studied members of the α/β-hydrolase fold family. Structural superposition onto representative α/β-hydrolase fold proteins of known function indicates that a possible catalytic nucleophile, Ser116 in the T. brucei protein, lies at the expected location. However, the present structure and by extension the other trypanosomatid members of this sequence family have neither sequence nor structural similarity at the location of other active-site residues typical for proteins with this fold. Together with the presence of an additional domain between strands β6 and β7 that is conserved in trypanosomatid genomes, this suggests that the function of these homologs has diverged from other members of the fold family

  6. Immobilization of NTPDase-1 from Trypanosoma cruzi and Development of an Online Label-Free Assay.

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    Calil, Felipe Antunes; Lima, Juliana Maria; de Oliveira, Arthur Henrique Cavalcante; Mariotini-Moura, Christiane; Fietto, Juliana Lopes Rangel; Cardoso, Carmen Lucia

    2016-01-01

    The use of IMERs (Immobilized Enzyme Reactors) as a stationary phase coupled to high performance chromatographic systems is an interesting approach in the screening of new ligands. In addition, IMERs offer many advantages over techniques that employ enzymes in solution. The enzyme nucleoside triphosphate diphosphohydrolase (NTPDase-1) from Trypanosoma cruzi acts as a pathogen infection facilitator, so it is a good target in the search for inhibitors. In this paper, immobilization of NTPDase-1 afforded ICERs (Immobilized Capillary Enzyme Reactors). A liquid chromatography method was developed and validated to monitor the ICER activity. The conditions for the application of these bioreactors were investigated, and excellent results were obtained. The enzyme was successfully immobilized, as attested by the catalytic activity detected in the Tc NTPDase-1-ICER chromatographic system. Kinetic studies on the substrate ATP gave K M of 0.317 ± 0.044 mmol·L -1 , which still presented high affinity compared to in solution. Besides that, the ICER was stable for 32 days, enough time to investigate samples of possible inhibitors, including especially the compound Suramin, that inhibited 51% the enzyme activity at 100  µ mol·L -1 , which is in accordance with the data for the enzyme in solution.

  7. Immobilization of NTPDase-1 from Trypanosoma cruzi and Development of an Online Label-Free Assay

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    Felipe Antunes Calil

    2016-01-01

    Full Text Available The use of IMERs (Immobilized Enzyme Reactors as a stationary phase coupled to high performance chromatographic systems is an interesting approach in the screening of new ligands. In addition, IMERs offer many advantages over techniques that employ enzymes in solution. The enzyme nucleoside triphosphate diphosphohydrolase (NTPDase-1 from Trypanosoma cruzi acts as a pathogen infection facilitator, so it is a good target in the search for inhibitors. In this paper, immobilization of NTPDase-1 afforded ICERs (Immobilized Capillary Enzyme Reactors. A liquid chromatography method was developed and validated to monitor the ICER activity. The conditions for the application of these bioreactors were investigated, and excellent results were obtained. The enzyme was successfully immobilized, as attested by the catalytic activity detected in the TcNTPDase-1-ICER chromatographic system. Kinetic studies on the substrate ATP gave KM of 0.317 ± 0.044 mmol·L−1, which still presented high affinity compared to in solution. Besides that, the ICER was stable for 32 days, enough time to investigate samples of possible inhibitors, including especially the compound Suramin, that inhibited 51% the enzyme activity at 100 µmol·L−1, which is in accordance with the data for the enzyme in solution.

  8. Interaction between Didelphis albiventris and Triatoma infestans in relation to Trypanosoma cruzi transmission

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    Nicolás J. Schweigmann

    1995-12-01

    Full Text Available This paper attempts to prove if a high Trypanosoma cruzi prevalence of opossums might be reached with few potential infective contacts. One non-infected Didelphis albiventris to T. cruzi and 10 infected nymphs of Triatoma infestans were left together during 23 hr in a device that simulated a natural opossum burrow. Twenty-six replicates were perfomed using marsupials and triatomines only once. Potentially infective contacts occurred in all the trials. From the 26 opossums used in trials, 54% did not eat any bug. Of the 260 bugs used, 21% were predated. In the 25 trials involving 205 surving bugs, 36 % of them did not feed. In 15/25 cases, maior ou igual a 60% of the triatomines were able to feed. The parasitological follow-up of 24 opossums showed that among 10 that had eaten bugs, 4 turned out infected and among the 14 that had not predate, 3 (21% became positive. In sum, 7/24 (29% of the marsupials acquired the infection after the experiment. This infection rate was similar to the prevalences found for the opossum population of Santiago del Estero, Argentina, suggesting that the prevalences observed in the field might be reached if each marsupial would encounter infected bugs just once in its lifetime.

  9. Studying nanotoxic effects of CdTe quantum dots in Trypanosoma cruzi

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    Cecilia Stahl Vieira

    2011-03-01

    Full Text Available Semiconductor nanoparticles, such as quantum dots (QDs, were used to carry out experiments in vivo and ex vivo with Trypanosoma cruzi. However, questions have been raised regarding the nanotoxicity of QDs in living cells, microorganisms, tissues and whole animals. The objective of this paper was to conduct a QD nanotoxicity study on living T. cruzi protozoa using analytical methods. This was accomplished using in vitro experiments to test the interference of the QDs on parasite development, morphology and viability. Our results show that after 72 h, a 200 μM cadmium telluride (CdTe QD solution induced important morphological alterations in T. cruzi, such as DNA damage, plasma membrane blebbing and mitochondrial swelling. Flow cytometry assays showed no damage to the plasma membrane when incubated with 200 μM CdTe QDs for up to 72 h (propidium iodide cells, giving no evidence of classical necrosis. Parasites incubated with 2 μM CdTe QDs still proliferated after seven days. In summary, a low concentration of CdTe QDs (2 μM is optimal for bioimaging, whereas a high concentration (200 μM CdTe could be toxic to cells. Taken together, our data indicate that 2 μM QD can be used for the successful long-term study of the parasite-vector interaction in real time.

  10. Flux Analysis of the Trypanosoma brucei Glycolysis Based on a Multiobjective-Criteria Bioinformatic Approach

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    Amine Ghozlane

    2012-01-01

    Full Text Available Trypanosoma brucei is a protozoan parasite of major of interest in discovering new genes for drug targets. This parasite alternates its life cycle between the mammal host(s (bloodstream form and the insect vector (procyclic form, with two divergent glucose metabolism amenable to in vitro culture. While the metabolic network of the bloodstream forms has been well characterized, the flux distribution between the different branches of the glucose metabolic network in the procyclic form has not been addressed so far. We present a computational analysis (called Metaboflux that exploits the metabolic topology of the procyclic form, and allows the incorporation of multipurpose experimental data to increase the biological relevance of the model. The alternatives resulting from the structural complexity of networks are formulated as an optimization problem solved by a metaheuristic where experimental data are modeled in a multiobjective function. Our results show that the current metabolic model is in agreement with experimental data and confirms the observed high metabolic flexibility of glucose metabolism. In addition, Metaboflux offers a rational explanation for the high flexibility in the ratio between final products from glucose metabolism, thsat is, flux redistribution through the malic enzyme steps.

  11. Domestic Pig (Sus scrofa) as an Animal Model for Experimental Trypanosoma cruzi Infection

    Science.gov (United States)

    Yauri, Verónica; Castro-Sesquen, Yagahira E.; Verastegui, Manuela; Angulo, Noelia; Recuenco, Fernando; Cabello, Ines; Malaga, Edith; Bern, Caryn; Gavidia, Cesar M.; Gilman, Robert H.

    2016-01-01

    Pigs were infected with a Bolivian strain of Trypanosoma cruzi (genotype I) and evaluated up to 150 days postinoculation (dpi) to determine the use of pigs as an animal model of Chagas disease. Parasitemia was observed in the infected pigs during the acute phase (15–40 dpi). Anti-T.cruzi immunoglobulin M was detected during 15–75 dpi; high levels of anti-T.cruzi immunoglobulin G were detected in all infected pigs from 75 to 150 dpi. Parasitic DNA was observed by western blot (58%, 28/48) and polymerase chain reaction (27%, 13/48) in urine samples, and in the brain (75%, 3/4), spleen (50%, 2/4), and duodenum (25%, 1/4), but no parasitic DNA was found in the heart, colon, and kidney. Parasites were not observed microscopically in tissues samples, but mild inflammation, vasculitis, and congestion was observed in heart, brain, kidney, and spleen. This pig model was useful for the standardization of the urine test because of the higher volume that can be obtained as compared with other small animal models. However, further experiments are required to observe pathological changes characteristic of Chagas disease in humans. PMID:26928841

  12. Potential Role of Carvedilol in the Cardiac Immune Response Induced by Experimental Infection with Trypanosoma cruzi

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    Aline Luciano Horta

    2017-01-01

    Full Text Available Trypanosoma cruzi causes a cardiac infection characterized by an inflammatory imbalance that could become the inciting factor of the illness. To this end, we evaluated the role of carvedilol, a beta-blocker with potential immunomodulatory properties, on the immune response in C57BL/6 mice infected with VL-10 strain of T. cruzi in the acute phase. Animals (n=40 were grouped: (i not infected, (ii infected, (iii infected + carvedilol, and (iv not infected + carvedilol. We analyzed parameters related to parasitemia, plasma levels of TNF, IL-10, and CCL2, and cardiac histopathology after the administration of carvedilol for 30 days. We did not observe differences in the maximum peaks of parasitemia in the day of their detection among the groups. The plasma TNF was elevated at 60 days of infection in mice treated or not with carvedilol. However, we observed a decreased CCL2 level and increased IL-10 levels in those infected animals treated with carvedilol, which impacted the reduction of the inflammatory infiltration in cardiac tissue. For this experimental model, carvedilol therapy was not able to alter the levels of circulating parasites but modulates the pattern of CCL2 and IL-10 mediators when the VL10 strain of T. cruzi was used in C57BL6 mice.

  13. Influence of environmental enrichment on the behavior and physiology of mice infected by Trypanosoma cruzi

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    Déborah Maria Moreira da Silva

    Full Text Available Abstract INTRODUCTION: Enriched environments normally increase behavioral repertoires and diminish the expression of abnormal behaviors and stress-related physiological problems in animals. Although it has been shown that experimental animals infected with microorganisms can modify their behaviors and physiology, few studies have evaluated how environmental enrichment affects these parameters. This study aimed to evaluate the effects of environmental enrichment on the behavior and physiology of confined mice infected with Trypanosoma cruzi. METHODS: The behaviors of 20 T. cruzi-infected mice and 20 non-infected mice were recorded during three treatments: baseline, enrichment, and post-enrichment. Behavioral data were collected using scan sampling with instantaneous recording of behavior every 30s, totaling 360h. Plasma TNF, CCL2, and IL-10 levels and parasitemia were also evaluated in infected enriched/non-enriched mice. Behavioral data were evaluated by Friedman’s test and physiological data by one-way ANOVA and area under the curve (AUC analysis. RESULTS: Results showed that environmental enrichment significantly increased exploratory behaviors and diminished inactivity. The use of environmental enrichment did not diminish circulating levels of TNF and IL-10 but diminished circulating levels of CCL2 and parasitemia. CONCLUSIONS: Positive behavioral and physiological effects of environmental enrichment were observed in mice living in enriched cages. Thus, environmental enrichment improved the welfare of these animals.

  14. Risk factors associated with Trypanosoma cruzi exposure in domestic dogs from a rural community in Panama.

    Science.gov (United States)

    Saldaña, Azael; Calzada, José E; Pineda, Vanessa; Perea, Milixa; Rigg, Chystrie; González, Kadir; Santamaria, Ana Maria; Gottdenker, Nicole L; Chaves, Luis F

    2015-11-01

    Chagas disease, caused by Trypanosoma cruzi infection, is a zoonosis of humans, wild and domestic mammals, including dogs. In Panama, the main T. cruzi vector is Rhodnius pallescens, a triatomine bug whose main natural habitat is the royal palm, Attalea butyracea. In this paper, we present results from three T. cruzi serological tests (immunochromatographic dipstick, indirect immunofluorescence and ELISA) performed in 51 dogs from 24 houses in Trinidad de Las Minas, western Panama. We found that nine dogs were seropositive (17.6% prevalence). Dogs were 1.6 times more likely to become T. cruzi seropositive with each year of age and 11.6 times if royal palms where present in the peridomiciliary area of the dog's household or its two nearest neighbours. Mouse-baited-adhesive traps were employed to evaluate 12 peridomestic royal palms. All palms were found infested with R. pallescens with an average of 25.50 triatomines captured per palm. Of 35 adult bugs analysed, 88.6% showed protozoa flagellates in their intestinal contents. In addition, dogs were five times more likely to be infected by the presence of an additional domestic animal species in the dog's peridomiciliary environment. Our results suggest that interventions focused on royal palms might reduce the exposure to T. cruzi infection.

  15. Electrocardiographic alteration among first degree relatives with serologic evidence of Trypanosoma cruzi infection: a sibship study

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    Julio C. Morini

    1994-09-01

    Full Text Available To analyze whether electrocardiographic alterations (ECGA in patients with antibodies to Trypanosoma cruzi showed a patttern of familial aggregation, a sample of 379 young adults (166 men and 213 women distributed in sibships, were assessed for the presence of anti-T.cruzi antibodies, and subjected to a complete clinical examination and a standard resting electrocardiogram (ECG. Positive T. cruzi serology was detected in 165 individuals, 48 of them showing an abnormal ECG (overall prevalence 29 por cento. One hundred and eleven seropositive individuals were distributed in 45 sibships, each of them constituted by more than one seropositive sib, with ECGA being present in 34 out of these patients. Seropositive subjects with ECGA were detected in 27 sibships. Since the index case within each sibship is counted exactly once, affected individuals selected at random as propositi were extracted to calculate the prevalence of ECGA among first degree relatives of probands. Abnormal ECGs were recorded in 7 out of 45 sibs yielding a prevalence that did not differ from estimations registered in the general population or seropositive sibs. Data from the present sample show no familial aggregation for the occurrence of ECGA in patients with T.cruzi infection.

  16. Is the anti-tumor property of Trypanosoma cruzi infection mediated by its Calreticulin?

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    Galia Andrea Ramírez-Toloza

    2016-07-01

    Full Text Available Eight to 10 million people in 21 endemic countries are infected with Trypanosoma cruzi. However, only 30% of those infected develop symptoms of Chagas’ disease, a chronic, neglected tropical disease worldwide. Similar to other pathogens, T. cruzi has evolved to resist the host immune response. Studies, performed 80 years ago in the Soviet Union, proposed that T. cruzi infects tumor cells with similar capacity to that displayed for target tissues such as cardiac, aortic or digestive. An antagonistic relationship between T. cruzi infection and cancer development was also proposed, but the molecular mechanisms involved have remained largely unknown. Probably, a variety of T. cruzi molecules is involved. This review focuses on how T. cruzi calreticulin (TcCRT, exteriorized from the endoplasmic reticulum, targets the first classical complement component C1 and negatively regulates the Classical Complement activation cascade, promoting parasite infectivity. We propose that this C1-dependent TcCRT-mediated virulence is critical to explain, at least an important part, of the parasite capacity to inhibit tumor development. We will discuss how TcCRT, by directly interacting with venous and arterial endothelial cells, inhibits angiogenesis and tumor growth. Thus, these TcCRT functions not only illustrate T. cruzi interactions with the host immune defensive strategies, but also illustrate a possible co-evolutionary adaptation to privilege a prolonged interaction with its host.

  17. Morphometry of submucous and myenteric esophagic plexus of dogs experimentally reinfected with Trypanosoma cruzi

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    Machado Evandro MM

    2001-01-01

    Full Text Available We carried out a morphometric study of the esophagus of cross-bred dogs experimentally infected or consecutively reinfected with Trypanosoma cruzi 147 and SC-1 strains, in order to verify denervation and/or neuronal hypertrophy in the intramural plexus. The animals were sacrificed in the chronic stage, 38 months after the initial infection. Neither nests of amastigotes, nor myositis or ganglionitis, were observed in all third inferior portions of esophageal rings analyzed. No nerve cell was identified in the submucous of this organ. There was no significant difference (p>0.05 between the number, maximum diameter, perimeter, or area and volume of the nerve cells of the myenteric plexus of infected and/or reinfected dogs and of the non-infected ones. In view of these results we may conclude that the 147 and SC-1 strains have little neurotropism and do not determine denervation and/or hypertrophy in the intramural esophageal plexuses in the animals studied, independent of the reinfections.

  18. Decay-accelerating factor 1 deficiency exacerbates Trypanosoma cruzi-induced murine chronic myositis.

    Science.gov (United States)

    Solana, María E; Ferrer, María F; Novoa, María Mercedes; Song, Wen-Chao; Gómez, Ricardo M

    2012-10-01

    Murine infection with Trypanosoma cruzi (Tc) has been used to study the role of T-cells in the pathogenesis of human inflammatory idiopathic myositis. Absence of decay-accelerating factor 1 (Daf1) has been shown to enhance murine T-cell responses and autoimmunity. To determine whether Daf1 deficiency can exacerbate Tc-induced myositis, C57BL/6 DAF(+/+) and DAF(-/-) mice were inoculated with 5 × 10(4) trypomastigotes, and their morbidity, parasitemia, parasite burden, histopathology, and T-cell expansion were studied in the acute and chronic stages. DAF(-/-) mice had lower parasitemia and parasite burden but higher morbidity, muscle histopathology, and increased number of CD44(+) (activated/memory phenotype) splenic CD4(+) and CD8(+) T-cells. An enhanced CD8(+) T-cell immune-specific response may explain the lower parasitemia and parasite burden levels and the increase in histopathological lesions. We propose that Tc-inoculated DAF(-/-) mice are a useful model to study T-cell mediated immunity in skeletal muscle tissues. Copyright © 2012 Wiley Periodicals, Inc.

  19. Effects of buthionine sulfoximine nifurtimox and benznidazole upon trypanothione and metallothionein proteins in Trypanosoma cruzi.

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    JUAN DIEGO MAYA

    2004-01-01

    Full Text Available Proteins rich in sulfhydryl groups, such as metallothionein, are present in several strains of the parasite Trypanosoma cruzi, the etiological agent of Chagas' disease. Metallothionein-like protein concentrations ranged from 5.1 to 13.2 pmol/mg protein depending on the parasite strain and growth phase. Nifurtimox and benznidazole, used in the treatment of Chagas' disease, decreased metallothionein activity by approximately 70%. T. cruzi metallothionein was induced by ZnCl2. Metallothionein from T. cruzi was partially purified and its monobromobimane derivative showed a molecular weight of approximately 10,000 Da by SDS-PAGE analysis. The concentration of trypanothione, the major glutathione conjugate in T. cruzi, ranged from 3.8 to 10.8 nmol/mg protein, depending on the culture phase. The addition of buthionine sulfoximine to the protozoal culture considerably reduced the concentration of trypanothione and had no effect upon the metallothionein concentration. The possible contribution of metallothionein-like proteins to drug resistance in T. cruzi is discussed.

  20. [Entomological study of Trypanosoma cruzi vectors in the rural communities of Sucre state, Venezuela].

    Science.gov (United States)

    García-Jordán, Noris; Berrizbeitia, Mariolga; Concepción, Juan Luis; Aldana, Elis; Cáceres, Ana; Quiñones, Wilfredo

    2015-01-01

    The ecological niche of Reduvidae vectors has been modified due to environmental changes and human encroachment into the rural areas. This study evaluates the current entomological indices of triatomines responsible for Trypanosoma cruzi infection in Sucre State, Venezuela. A cross-sectional and prospective study was conducted in 95 towns and 577 dwellings in the 15 municipalities of the state of Sucre, Venezuela, from August to November, 2008. Triatomine bugs were identified on the basis of morphological characteristics, and their feces examined for T. cruzi infection through direct microscopy. Positive slides were stained with Giemsa and parasites were identified by morphologic characterization. The entomological indices expressing the highest values were dispersion (16.67%) and household colonization (33.33%). The triatomine species captured were: Rhodnius prolixus , Rhodnius main intradomiciliary vector. Despite the low index of vector infection (1.72%), the existence of species with domiciliary and peridomiciliary reproductive success ensures the persistence of the epidemiological chain both for the disease and the parasite.

  1. Design of Trypanosoma rangeli sialidase mutants with improved trans-sialidase activity.

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    Christian Nyffenegger

    Full Text Available A sialidase (EC 3.2.1.18 from the non-pathogenic Trypanosoma rangeli, TrSA, has been shown to exert trans-sialidase activity after mutation of five specific amino acids in the active site (M96V, A98P, S120Y, G249Y, Q284P to form the so-called TrSA5mut enzyme. By computational and hypothesis driven approaches additional mutations enhancing the trans-sialidase activity have been suggested. In the present work, we made a systematic combination of these mutations leading to seven new variants of the T. rangeli sialidase, having 6-16 targeted amino acid mutations. The resulting enzyme variants were analyzed via kinetics for their ability to carry out trans-sialidase reaction using CGMP and D-lactose as substrates. The sialidase variants with 15 and 16 mutations, respectively, exhibited significantly improved trans-sialidase activity for D-lactose sialylation. Our results corroborate, that computational studies of trans-glycosylation can be a valuable input in the design of novel trans-glycosidases, but also highlight the importance of experimental validation in order to assess the performance. In conclusion, two of the seven mutants displayed a dramatic switch in specificity from hydrolysis towards trans-sialylation and constitute the most potent trans-sialidase mutants of TrSA described in literature to date.

  2. Identification of TOEFAZ1-interacting proteins reveals key regulators of Trypanosoma brucei cytokinesis.

    Science.gov (United States)

    Hilton, Nicholas A; Sladewski, Thomas E; Perry, Jenna A; Pataki, Zemplen; Sinclair-Davis, Amy N; Muniz, Richard S; Tran, Holly L; Wurster, Jenna I; Seo, Jiwon; de Graffenried, Christopher L

    2018-05-21

    The protist parasite Trypanosoma brucei is an obligate extracellular pathogen that retains its highly-polarized morphology during cell division and has evolved a novel cytokinetic process independent of non-muscle myosin II. The polo-like kinase homolog TbPLK is essential for transmission of cell polarity during division and for cytokinesis. We previously identified a putative TbPLK substrate named Tip of the Extending FAZ 1 (TOEFAZ1) as an essential kinetoplastid-specific component of the T. brucei cytokinetic machinery. We performed a proximity-dependent biotinylation (BioID) screen using TOEFAZ1 as a means to identify additional proteins that are involved in cytokinesis. Using quantitative proteomic methods, we identified nearly 500 TOEFAZ1-proximal proteins and characterized 59 in further detail. Among the candidates, we identified an essential putative phosphatase that regulates the expression level and localization of both TOEFAZ1 and TbPLK, a previously uncharacterized protein that is necessary for the assembly of a new cell posterior, and a microtubule plus-end directed orphan kinesin that is required for completing cleavage furrow ingression. The identification of these proteins provides new insight into T. brucei cytokinesis and establishes TOEFAZ1 as a key component of this essential and uniquely-configured process in kinetoplastids. This article is protected by copyright. All rights reserved. © 2018 John Wiley & Sons Ltd.

  3. Coadministration of cruzipain and GM-CSF DNAs, a new immunotherapeutic vaccine against Trypanosoma cruzi infection.

    Science.gov (United States)

    Cerny, Natacha; Sánchez Alberti, Andrés; Bivona, Augusto E; De Marzi, Mauricio C; Frank, Fernanda M; Cazorla, Silvia I; Malchiodi, Emilio L

    2016-01-01

    Therapeutic vaccine research and development are especially important in Chagas disease considering the characteristics of the chronic infection and the number of people in the Americas living with a parasite infection for decades. We have previously reported the efficacy of attenuated Salmonella enterica (S) carrying plasmid encoding cruzipain (SCz) to protect against Trypanosoma cruzi infection. In the present work we investigated whether Cz DNA vaccine immunotherapy could be effective in controlling an ongoing T. cruzi infection in mice. We here report the intramuscular administration of naked Cz DNA or the oral administration of Salmonella as Cz DNA delivery system as therapeutic vaccines in mice during acute or chronic infection. The coadministration of a plasmid encoding GM-CSF improved vaccine performance, indicating that the stimulation of innate immune cells is needed in the event of an ongoing infection. These therapeutic vaccines were able to address the response to a protective and sustained Th1 biased profile not only against Cz but also against a variety of parasite antigens. The combined therapeutic vaccine during the chronic phase of infection prevents tissue pathology as shown by a reduced level of enzyme activity characteristic of tissue damage and a tissue status compatible with normal tissue. The obtained results suggest that immunotherapy with Cz and GM-CSF DNAs, either alone or in combination with other drug treatments, may represent a promising alternative for Chagas disease therapy.

  4. The Acute Phase of Trypanosoma cruzi Infection Is Attenuated in 5-Lipoxygenase-Deficient Mice

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    Adriana M. C. Canavaci

    2014-01-01

    Full Text Available In the present work we examine the contribution of 5-lipoxygenase- (5-LO- derived lipid mediators to immune responses during the acute phase of Trypanosoma cruzi infection in 5-LO gene knockout (5-LO−/− mice and wild-type (WT mice. Compared with WT mice, the 5-LO−/− mice developed less parasitemia/tissue parasitism, less inflammatory cell infiltrates, and a lower mortality. This resistance of 5-LO−/− mice correlated with several differences in the immune response to infection, including reduced PGE2 synthesis; sustained capacity of splenocytes to produce high levels of interleukin (IL-12 early in the infection; enhanced splenocyte production of IL-1β, IL-6, and IFN-γ; rapid T-cell polarization to secrete high quantities of IFN-γ and low quantities of IL-10; and greater numbers of CD8+CD44highCD62Llow memory effector T cells at the end of the acute phase of infection. The high mortality in WT mice was associated with increased production of LTB4/LTC4, T cell bias to produce IFN-γ, high levels of serum nitrite, and marked protein extravasation into the peritoneal cavity, although survival was improved by treatment with a cys-LT receptor 1 antagonist. These data also provide evidence that 5-LO-derived mediators negatively affect host survival during the acute phase of T. cruzi infection.

  5. Standardization of serological tests for detecting anti-Trypanosoma cruzi antibodies in dogs

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    M. A. Lauricella

    1993-09-01

    Full Text Available This paper reports on the standardization of four serological reactions currently used in human serodiagnosis for the detection of anti-Trypanosoma cruzi antibodies in naturally and experimentally infected dogs. Indirect immunofluorescence test (IFAT and hemagglutination test (IHAT were standardized, and complement fixation test (CFT and direct agglutination test (DAT were used for diagnostic confirmation. Four hundred and eighty one mongrel dogs that were studied by xenodiagnosis were used: (1 parasitemic dogs of two localities of endemic area (EA of Santiago del Estero province in Argentina (n = 134; (2 non-parasitemic dogs of the same area (n = 285; (3 dogs experimentally infected with T. cruzi in the patent period (n = 6; (4 non-infected dogs (n = 56 which were born in the city of Buenos Aires (BA, one non-EA for Chagas' disease. For IFAT, parasitemic dogs EA showed 95% of reactive sera. Non parasitemic dogs EA showed 77% of non reactive sera. None sera from BA were reactive for dilutions higher than four. For IHAT, 84% of sera of parasitemic dogs EA showed serological reactivity and among non parasitemic dogs BA, 61% were non reactive, while the remainder showed at most titres of 1/16. The cut-off titres for IFAT and IHAT were 1/16 and 1/32 respectively, and for CFT and DAT 1/1 and 1/128 respectively. Sensitivity for IFAT, IHAT, CF and DAT were 95%, 84%, 97% and 95% respectively.

  6. Trypanosoma cruzi benznidazole susceptibility in vitro does not predict the therapeutic outcome of human Chagas disease

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    Margoth Moreno

    2010-11-01

    Full Text Available Therapeutic failure of benznidazole (BZ is widely documented in Chagas disease and has been primarily associated with variations in the drug susceptibility of Trypanosoma cruzi strains. In humans, therapeutic success has been assessed by the negativation of anti-T. cruzi antibodies, a process that may take up to 10 years. A protocol for early screening of the drug resistance of infective strains would be valuable for orienting physicians towards alternative therapies, with a combination of existing drugs or new anti-T. cruzi agents. We developed a procedure that couples the isolation of parasites by haemoculture with quantification of BZ susceptibility in the resultant epimastigote forms. BZ activity was standardized with reference strains, which showed IC50 to BZ between 7.6-32 µM. The assay was then applied to isolates from seven chronic patients prior to administration of BZ therapy. The IC50 of the strains varied from 15.6 ± 3-51.4 ± 1 µM. Comparison of BZ susceptibility of the pre-treatment isolates of patients considered cured by several criteria and of non-cured patients indicates that the assay does not predict therapeutic outcome. A two-fold increase in BZ resistance in the post-treatment isolates of two patients was verified. Based on the profile of nine microsatellite loci, sub-population selection in non-cured patients was ruled out.

  7. Trypanocidal activity of Brazilian plants against epimastigote forms from Y and Bolivia strains of Trypanosoma cruzi

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    Renata Tomé Alves

    2012-01-01

    Full Text Available Chagas disease is one of the main public health problems in Latin America. Since the available treatments for this disease are not effective in providing cure, the screening of potential antiprotozoal agents is essential, mainly of those obtained from natural sources. This study aimed to provide an evaluation of the trypanocidal activity of 92 ethanol extracts from species belonging to the families Annonaceae, Apiaceae, Cucurbitaceae, Lamiaceae, Lauraceae, Moraceae, Nyctaginaceae, and Verbenaceae against the Y and Bolivia strains of Trypanosoma cruzi. Additionally, cytotoxic activity on LLCMK2 fibroblasts was evaluated. Both the trypanocidal activity and cytotoxicity were evaluated using the MTT method, in the following concentrations: 500, 350, 250, and 100 µg/mL. Benznidazole was used for positive control. The best results among the 92 samples evaluated were obtained with ethanol extracts of Ocotea paranapiacabensis (Am93 and Aegiphila lhotzkiana (Am160. Am93 showed trypanocidal activity against epimastigote forms of the Bolivia strain and was moderately toxic to LLCMK2 cells, its Selectivity Index (SI being 14.56, while Am160 showed moderate trypanocidal activity against the Bolivia strain and moderate toxicicity, its SI being equal to 1.15. The screening of Brazilian plants has indicated the potential effect of ethanol extracts obtained from Ocotea paranapiacabensis and Aegiphila lhotzkiana against Chagas disease.

  8. Identification and characterization of a stage specific membrane protein involved in flagellar attachment in Trypanosoma brucei.

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    Katherine Woods

    Full Text Available Flagellar attachment is a visibly striking morphological feature of African trypanosomes but little is known about the requirements for attachment at a molecular level. This study characterizes a previously undescribed membrane protein, FLA3, which plays an essential role in flagellar attachment in Trypanosoma brucei. FLA3 is heavily N-glycosylated, locates to the flagellar attachment zone and appears to be a bloodstream stage specific protein. Ablation of the FLA3 mRNA rapidly led to flagellar detachment and a concomitant failure of cytokinesis in the long slender bloodstream form but had no effect on the procyclic form. Flagellar detachment was obvious shortly after induction of the dsRNA and the newly synthesized flagellum was often completely detached after it emerged from the flagellar pocket. Within 12 h most cells possessed detached flagella alongside the existing attached flagellum. These results suggest that proteins involved in attachment are not shared between the new and old attachment zones. In other respects the detached flagella appear normal, they beat rapidly although directional motion was lost, and they possess an apparently normal axoneme and paraflagellar rod structure. The flagellar attachment zone appeared to be disrupted when FLA3 was depleted. Thus, while flagellar attachment is a constitutive feature of the life cycle of trypanosomes, attachment requires stage specific elements at the protein level.

  9. Immunodiagnosis of Trypanosoma cruzi (Chagas' Disease Infection in Naturally Infected Dogs

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    Lauricella MA

    1998-01-01

    Full Text Available This study reports on the standardization of an enzyme-linked immunosorbent assay (ELISA for detecting specific antibodies anti-Trypanosoma cruzi in naturally infected dogs. Sera from 182 mongrel dogs of all ages residing in four rural villages in Santiago del Estero, Argentina, were collected in November 1994 and preserved in buffered neutral glycerin. All sera were tested by indirect hemagglutination test (IHAT, indirect immunofluorescence test (IFAT, and ELISA using the flagellar fraction of T. cruzi as antigen. Dog sera from an area without vectorial transmission were used to calculate ELISA specificity and cut-off value. Eighty-six percent of sera had concordant results for all tests. All sera reactive for IHAT and IFAT were also reactive for ELISA, except in one case. Sera tested by ELISA when diluted 1:200 allowed a clearer division between non-reactive and reactive sera than when 1:100 with greater agreement among serologic techniques. The specificity of ELISA was 96.2%. Among 34 adult dogs with a positive xenodiagnosis, sensitivity was 94% both for ELISA and IFAT. ELISA is the first choice for screening purposes and one of the pair of techniques recommended for diagnostic studies in dog populations

  10. Trypanosoma cruzi: effects of azadirachtin and ecdysone on the dynamic development in Rhodnius prolixus larvae.

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    Cortez, M R; Provençano, A; Silva, C E; Mello, C B; Zimmermann, L T; Schaub, G A; Garcia, E S; Azambuja, P; Gonzalez, M S

    2012-07-01

    The effects of azadirachtin and ecdysone on the Trypanosoma cruzi population in the Rhodnius prolixus gut were investigated. T. cruzi were rarely found in the gut compartments of azadirachtin-treated larvae. High parasite numbers were observed in the stomach of the control and ecdysone groups until 10 days after treatment and in the small intestine and rectum until 25 days after treatment. High percentages of round forms developed in the stomachs of all groups, whereas azadirachtin blocked the development of protozoan intermediate forms. This effect was counteracted by ecdysone therapy. In the small intestine and rectum, epimastigotes predominated for all groups, but more of their intermediates developed in the control and ecdysone groups. Azadirachtin supported the development of round forms and their intermediates into trypomastigotes. In the rectum, trypomastigotes did not develop in the azadirachtin group and developed much later after ecdysone therapy. The parallel between the effects of azadirachtin and ecdysone on the host and parasite development is discussed on the basis of the present results because ecdysone appears to act directly or indirectly in determining the synchronic development of T. cruzi forms from round to epimastigotes, but not metacyclic trypomastigotes, in the invertebrate vector. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Limited antigenic variation in the Trypanosoma cruzi candidate vaccine antigen TSA-1.

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    Knight, J M; Zingales, B; Bottazzi, M E; Hotez, P; Zhan, B

    2014-12-01

    Chagas disease (American trypanosomiasis caused by Trypanosoma cruzi) is one of the most important neglected tropical diseases in the Western Hemisphere. The toxicities and limited efficacies of current antitrypanosomal drugs have prompted a search for alternative technologies such as a therapeutic vaccine comprised of T. cruzi antigens, including a recombinant antigen encoding the N-terminal 65 kDa portion of Trypomastigote surface antigen-1 (TSA-1). With at least six known genetically distinct T. cruzi lineages, variability between the different lineages poses a unique challenge for the development of broadly effective therapeutic vaccine. The variability across the major lineages in the current vaccine candidate antigen TSA-1 has not previously been addressed. To assess the variation in TSA-1, we cloned and sequenced TSA-1 from several different T. cruzi strains representing three of the most clinically relevant lineages. Analysis of the different alleles showed limited variation in TSA-1 across the different strains and fit with the current theory for the evolution of the different lineages. Additionally, minimal variation in known antigenic epitopes for the HLA-A 02 allele suggests that interlineage variation in TSA-1 would not impair the range and efficacy of a vaccine containing TSA-1. © 2014 John Wiley & Sons Ltd.

  12. Trypanosoma (Herpetosoma rangeli Tejera, 1920: intracellular amastigote stages of reproduction in white mice

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    Servio Urdaneta-Morales

    1986-06-01

    Full Text Available The method, site, and stage of multiplication of Trypanosoma (Herpetosoma rangeli Tejera, 1920 has not hitherto been known. "We have now observed many intracellular nests or pseudocysts, containing amastigotes and trypomastigotes of this parasite in the heart, liver, and spleen of suckling (5.0 g male white mice (NMRI strain inoculated i.p. with 9 x 10(4 metatrypomastigotes/g body weight from a 12-day-old culture of the "Dog-82" strain of T. rangeli. At the peak of parasitemia (1.9 x 10(6 trypomastigotes/ml blood, 3 days post-inoculation various tissues were taken for sectioning and staining. The heart was most intensely parasitized. The amastigotes were rounded or ellipsoidal, with a rounded nucleus and the kinetoplast in the form of a straight or curved bar; the average maximum diameter of 50 measured amastigotes was 4.2 p. Binary fission was seen in the nucleus and kinetoplast of some amastigotes; no blood trypomastigotes were seen in division. The above characteristics, as well as the location of the pseudocysts in the tissues, are similar to T. cruzi. Comparison of these results with those reported for other Herpetosoma suggest study of the taxonomic position of T. rangeli.

  13. Myenteric plexus is differentially affected by infection with distinct Trypanosoma cruzi strains in Beagle dogs

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    Nívia Carolina Nogueira-Paiva

    2014-02-01

    Full Text Available Chagasic megaoesophagus and megacolon are characterised by motor abnormalities related to enteric nervous system lesions and their development seems to be related to geographic distribution of distinct Trypanosoma cruzi subpopulations. Beagle dogs were infected with Y or Berenice-78 (Be-78 T. cruzi strains and necropsied during the acute or chronic phase of experimental disease for post mortem histopathological evaluation of the oesophagus and colon. Both strains infected the oesophagus and colon and caused an inflammatory response during the acute phase. In the chronic phase, inflammatory process was observed exclusively in the Be-78 infected animals, possibly due to a parasitism persistent only in this group. Myenteric denervation occurred during the acute phase of infection for both strains, but persisted chronically only in Be-78 infected animals. Glial cell involvement occurred earlier in animals infected with the Y strain, while animals infected with the Be-78 strain showed reduced glial fibrillary acidic protein immunoreactive area of enteric glial cells in the chronic phase. These results suggest that although both strains cause lesions in the digestive tract, the Y strain is associated with early control of the lesion, while the Be-78 strain results in progressive gut lesions in this model.

  14. The Trypanosoma cruzi nucleolus: a morphometrical analysis of cultured epimastigotes in the exponential and stationary phases.

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    Nepomuceno-Mejía, Tomás; Lara-Martínez, Reyna; Cevallos, Ana María; López-Villaseñor, Imelda; Jiménez-García, Luis Felipe; Hernández, Roberto

    2010-12-01

    Our group is interested in rRNA and ribosome biogenesis in the parasitic protozoan Trypanosoma cruzi. Epimastigotes represent an extracellular replicative stage of T. cruzi and can be cultured in axenic media. The growth curve of epimastigotes allows assessment of potential differences in the nucleoli of cells undergoing growth-rate transitions. To establish cellular parameters for studying ribosome biogenesis in T. cruzi, a morphometric analysis of the nucleoli of cultured cells in the exponential and stationary phases was conducted. Electron micrograph-based measurements of nuclear sections from independent cells demonstrated that the nucleolar area is over twofold higher in exponentially growing cells, as compared with epimastigotes in the stationary phase. The granular component of the nucleoli of actively growing cells was the main structural element. Cycloheximide moderately reduced the apparent size of the nucleoli without an apparent disruption of their architecture. Our results provide a firm basis for the establishment of an experimental model to study the organization of the nucleolus during the growth and development of T. cruzi. © 2010 Federation of European Microbiological Societies Published by Blackwell Publishing Ltd. All rights reserved.

  15. Evaluation of some organic compounds on bloodstream forms of Trypanosoma cruzi

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    João S. Silva

    1992-09-01

    Full Text Available Accidental transmission of Chagas' disease to man by blood transfusion is a serious problem in Latin-America. This paper describes the testing of several synthetic, semi-synthetic, and natural compounds for their activity against blood trypomastigotes in vitro at 4-C. The compounds embody several types of chemical structures: benzoquinone, naphthoquinone, anthracenequinone, phenanthrenequinone, imidazole, piperazine, quinoline, xanthene, and simple benzenic and naphthalenic derivates. Some of them are for the first time tested against Trypanosoma cruzi. The toxic effect these compounds on this parasite was done by two quite distinct sets of experiments. In one set, the compounds were added to infected blood as ethanolic solution. In this situation the most active one was a furan-1, 2-naphthoquinone, in the same range as gentian violet, a new fact to be considered in the assessment of structure-activity relationships in this class of compounds. In other set, we tentatively evaluated the biological activity of water insoluble compounds by adding them in a pure form without solvent into infected blood. In this way some appear to be very active and it was postulated that the effectiveness of such compounds must result from interactions between them and specific blood components.

  16. Aldo-keto reductase and alcohol dehydrogenase contribute to benznidazole natural resistance in Trypanosoma cruzi.

    Science.gov (United States)

    González, Laura; García-Huertas, Paola; Triana-Chávez, Omar; García, Gabriela Andrea; Murta, Silvane Maria Fonseca; Mejía-Jaramillo, Ana M

    2017-12-01

    The improvement of Chagas disease treatment is focused not only on the development of new drugs but also in understanding mechanisms of action and resistance to drugs conventionally used. Thus, some strategies aim to detect specific changes in proteins between sensitive and resistant parasites and to evaluate the role played in these processes by functional genomics. In this work, we used a natural Trypanosoma cruzi population resistant to benznidazole, which has clones with different susceptibilities to this drug without alterations in the NTR I gene. Using 2DE-gel electrophoresis, the aldo-keto reductase and the alcohol dehydrogenase proteins were found up regulated in the natural resistant clone and therefore their possible role in the resistance to benznidazole and glyoxal was investigated. Both genes were overexpressed in a drug sensitive T. cruzi clone and the biological changes in response to these compounds were evaluated. The results showed that the overexpression of these proteins enhances resistance to benznidazole and glyoxal in T. cruzi. Moreover, a decrease in mitochondrial and cell membrane damage was observed, accompanied by a drop in the intracellular concentration of reactive oxygen species after treatment. Our results suggest that these proteins are involved in the mechanism of action of benznidazole. © 2017 John Wiley & Sons Ltd.

  17. Internalization of components of the host cell plasma membrane during infection by Trypanosoma cruzi

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    Carvalho TMU

    1999-01-01

    Full Text Available Epimastigote and trypomastigote forms of Trypanosoma cruzi attach to the macrophage surface and are internalized with the formation of a membrane bounded vacuole, known as the parasitophorous vacuole (PV. In order to determine if components of the host cell membrane are internalized during formation of the PV we labeled the macrophage surface with fluorescent probes for proteins, lipids and sialic acid residues and then allowed the labeled cells to interact with the parasites. The interaction process was interrupted after 1 hr at 37ºC and the distribution of the probes analyzed by confocal laser scanning microscopy. During attachment of the parasites to the macrophage surface an intense labeling of the attachment regions was observed. Subsequently labeling of the membrane lining the parasitophorous vacuole containing epimastigote and trypomastigote forms was seen. Labeling was not uniform, with regions of intense and light or no labeling. The results obtained show that host cell membrane lipids, proteins and sialoglycoconjugates contribute to the formation of the membrane lining the PV containing epimastigote and trypomastigote T. cruzi forms. Lysosomes of the host cell may participate in the process of PV membrane formation.

  18. Modulation of Trypanosoma cruzi-specific T-cell responses after chemotherapy for chronic Chagas disease

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    María Cecilia Albareda

    2015-05-01

    Full Text Available The aim of this review is to describe the contributions of the knowledge of T-cell responses to the understanding of the physiopathology and the responsiveness to etiological treatment during the chronic phase of Chagas disease. T-helper (Th1 and interleukin (IL-10 Trypanosoma cruzi-specific T-cells have been linked to the asymptomatic phase or to severe clinical forms of the disease, respectively or vice versa, depending on the T. cruzi antigen source, the patient’s location and the performed immunological assays. Parasite-specific T-cell responses are modulated after benznidazole (BZ treatment in chronically T. cruzi-infected subjects in association with a significant decrease in T. cruzi-specific antibodies. Accumulating evidence has indicated that treatment efficacy during experimental infection with T. cruzi results from the combined action of BZ and the activation of appropriate immune responses in the host. However, strong support of this interaction in T. cruzi-infected humans remains lacking. Overall, the quality of T-cell responses might be a key factor in not only disease evolution, but also chemotherapy responsiveness. Immunological parameters are potential indicators of treatment response regardless of achievement of cure. Providing tools to monitor and provide early predictions of treatment success will allow the development of new therapeutic options.

  19. The active transport of histidine and its role in ATP production in Trypanosoma cruzi.

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    Barisón, M J; Damasceno, F S; Mantilla, B S; Silber, A M

    2016-08-01

    Trypanosoma cruzi, the aetiological agent of Chagas's disease, metabolizes glucose, and after its exhaustion, degrades amino acids as energy source. Here, we investigate histidine uptake and its participation in energy metabolism. No putative genes for the histidine biosynthetic pathway have been identified in genome databases of T. cruzi, suggesting that its uptake from extracellular medium is a requirement for the viability of the parasite. From this assumption, we characterized the uptake of histidine in T. cruzi, showing that this amino acid is incorporated through a single and saturable active system. We also show that histidine can be completely oxidised to CO2. This finding, together with the fact that genes encoding the putative enzymes for the histidine - glutamate degradation pathway were annotated, led us to infer its participation in the energy metabolism of the parasite. Here, we show that His is capable of restoring cell viability after long-term starvation. We confirm that as an energy source, His provides electrons to the electron transport chain, maintaining mitochondrial inner membrane potential and O2 consumption in a very efficient manner. Additionally, ATP biosynthesis from oxidative phosphorylation was found when His was the only oxidisable metabolite present, showing that this amino acid is involved in bioenergetics and parasite persistence within its invertebrate host.

  20. Trypanosoma cruzi: partial prevention of the natural infection of guinea pigs with a killed parasite vaccine.

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    Basombrio, M A

    1990-07-01

    Guinea pigs are natural reservoirs of Chagas' disease. Domestic breeding and local trade of these animals are common practices among andean communities in South America. Infection by Trypanosoma cruzi occurs when the animals live in triatomine-infested houses or yards. The preventive effect of a vaccine consisting of cultured T. cruzi killed by freezing and thawing plus saponin was tested both in mice and in the guinea pig ecosystem. Resistance against T. cruzi challenge in mice was improved by increasing the trypomastigote/epimastigote ratio in live attenuated vaccines but not in killed parasite vaccines. Although the killing of attenuated parasites sharply reduced their immunogenicity for mice, a protective effect against natural T. cruzi infection was detected in guinea pigs. A total of 88 guinea pigs were vaccinated in four intradermal sites on three occasions. Eighty controls received similar inoculations of culture medium plus saponin. All animals were kept in a triatomine-infested yard. Parasitemia was studied with the capillary microhematocrit method. After an exposure time averaging 4 months, natural T. cruzi infection occurred in 55% (44/80) of the controls and in 33% (29/88) of the vaccinated group (P less than 0.01). The number of highly parasitemic guinea pigs was also significantly decreased (6/80 vs 0/88, P less than 0.01). Thus, immunizing protocols which are only partially protective against artificial callenge with T. cruzi may nevertheless constrain the exchange of parasites between natural hosts and vectors.

  1. [Seroprevalence of antibodies against Trypanosoma cruzi in 13 departments of Uruguay].

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    Salvatella, R; Calegari, L; Casserone, S; Civila, E; Carbajal, S; Pérez, G; Somma, R; Sampaio, I; Llanes, M E; Conti, M

    1989-08-01

    In 1985 a study was undertaken of the prevalence of Trypanosoma cruzi antibodies in 13 departments of Uruguay where transmission of the parasite by the vector Triatoma infestans persists. A total of 5,924 serum samples were selected using a probabilistic method--3,840 from individuals over the age of 12 (sample I) and 2,084 from subjects who were 12 years old (sample II). The population was classified according to place of residence (capital city, non-capital city, suburban area, and rural area). The percentage of positive sera detected by indirect immunofluorescence in the different departments ranged from 1 to 11%, and overall seroprevalence for the area was 3.4%. Based on the results obtained, it was possible to distinguish three areas: A, with seroprevalence from 6 to 11%; B, 2 to 3.2%, and C, 1 to 1.4%. In sample II from the Departments of Paysandú, Soriano, Flores, Florida, and Durazno, no cases of Chagas' disease were detected, which suggests that there is no active transmission of T. cruzi in this age group in the area studied. The number of persons estimated to have the disease was 36,952, or 1.3% of the total population of Uruguay and 4% of the population in the area surveyed. These seroprevalence figures are similar to those recorded in the province of Entre Ríos, Argentina, and in the neighboring municipalities of Rio Grande do Sul, Brazil.

  2. Notes on the occurrence of Trypanosoma sp. (Kinetoplastida: Trypanosomatidae in freshwater fishes from South Africa

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    Maryke L. Ferreira

    2013-03-01

    Full Text Available A total of 257 fishes from four families, Clariidae, Cichlidae, Cyprinidae and Schilbeidae were collected from three localities: the Sand River Dam, Swaziland; the Nylsvlei Nature Reserve, South Africa and the Vaal Dam and Vaal River Barrage, South Africa. Only fishes (n= 154 from Clariidae and Cichlidae were found to be infected with trypanosomes. A total of 221 Clarias gariepinus (Burchell 1822 were collected from the Vaal Dam and Vaal Barrage area, South Africa. Of these, 74%(89/121 were infected with trypanosomes from the Vaal Dam and 63%(63/100 from the Vaal River Barrage, with no seasonal infection pattern. A prevalence of 25%(1/4 was found in C. gariepinus from the Sand River Dam, Swaziland, and a 50% (1/2 prevalence was found in Tilapia sparrmanii from the Nylsvlei Nature Reserve, South Africa. Standard measurements conformed closely to the morphometric and morphological descriptions of Trypanosoma mukasai. This article provides new locality records for T. mukasai from the Vaal Dam, Vaal River Barrage and Nylsvlei Nature Reserve (South Africa and the Sand River Dam (Swaziland. Tilapia sparrmanii collected in the Sand River Dam in Swaziland is also noted as a new host record.

  3. Astrocyte Apoptosis and HIV Replication Are Modulated in Host Cells Coinfected with Trypanosoma cruzi

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    Javier M. Urquiza

    2017-08-01

    Full Text Available The protozoan Trypanosoma cruzi is the etiological agent of Chagas disease. In immunosuppressed individuals, as it occurs in the coinfection with human immunodeficiency virus (HIV, the central nervous system may be affected. In this regard, reactivation of Chagas disease is severe and often lethal, and it accounts for meningoencephalitis. Astrocytes play a crucial role in the environment maintenance of healthy neurons; however, they can host HIV and T. cruzi. In this report, human astrocytes were infected in vitro with both genetically modified-pathogens to express alternative fluorophore. As evidenced by fluorescence microscopy and flow cytometry, HIV and T. cruzi coexist in the same astrocyte, likely favoring reciprocal interactions. In this context, lower rates of cell death were observed in both T. cruzi monoinfected-astrocytes and HIV-T. cruzi coinfection in comparison with those infected only with HIV. The level of HIV replication is significantly diminished under T. cruzi coinfection, but without affecting the infectivity of the HIV progeny. This interference with viral replication appears to be related to the T. cruzi multiplication rate or its increased intracellular presence but does not require their intracellular cohabitation or infected cell-to-cell contact. Among several Th1/Th2/Th17 profile-related cytokines, only IL-6 was overexpressed in HIV-T. cruzi coinfection exhibiting its cytoprotective role. This study demonstrates that T. cruzi and HIV are able to coinfect astrocytes thus altering viral replication and apoptosis.

  4. Novel sterol metabolic network of Trypanosoma brucei procyclic and bloodstream forms

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    Nes, Craigen R.; Singha, Ujjal K.; Liu, Jialin; Ganapathy, Kulothungan; Villalta, Fernando; Waterman, Michael R.; Lepesheva, Galina I.; Chaudhuri, Minu; Nes, W. David

    2012-01-01

    Trypanosoma brucei is the protozoan parasite that causes African trypanosomiasis, a neglected disease of people and animals. Co-metabolite analysis, labelling studies using [methyl-2H3]-methionine and substrate/product specificities of the cloned 24-SMT (sterol C24-methyltransferase) and 14-SDM (sterol C14-demethylase) from T. brucei afforded an uncommon sterol metabolic network that proceeds from lanosterol and 31-norlanosterol to ETO [ergosta-5,7,25(27)-trien-3β-ol], 24-DTO [dimethyl ergosta-5,7,25(27)-trienol] and ergosterol [ergosta-5,7,22(23)-trienol]. To assess the possible carbon sources of ergosterol biosynthesis, specifically 13C-labelled specimens of lanosterol, acetate, leucine and glucose were administered to T. brucei and the 13C distributions found were in accord with the operation of the acetate–mevalonate pathway, with leucine as an alternative precursor, to ergostenols in either the insect or bloodstream form. In searching for metabolic signatures of procyclic cells, we observed that the 13C-labelling treatments induce fluctuations between the acetyl-CoA (mitochondrial) and sterol (cytosolic) synthetic pathways detected by the progressive increase in 13C-ergosterol production (control sterol synthesis that is further fluctuated in the cytosol, yielding distinct sterol profiles in relation to cell demands on growth. PMID:22176028

  5. Immunoglobulin M antibodies against CRA and FRA recombinant antigens of Trypanosoma cruzi in chronic chagasic patients.

    Science.gov (United States)

    Vasconcelos, Romero H T; Azevedo, Elisa A N; Cavalcanti, Maria G A M; Silva, Edimilson D; Ferreira, Antonio G P; Morais, Clarice N L; Gomes, Yara M

    2011-05-01

    Previous works of our research group have demonstrated aspects of the humoral immune response of chronic Chagas disease using the cytoplasmatic repetitive antigen (CRA) and the flagellar repetitive antigen (FRA) of Trypanosoma cruzi. The aim of this work was to analyze the presence of specific immunoglobulin M (IgM) antibodies in chronic chagasic patients using these recombinant antigens of T. cruzi. The positivity of IgM in chronic chagasic patients against CRA and FRA antigens was determined by indirect enzyme-linked immunosorbent assay. We reported no statistical significant differences between the levels of IgM for both recombinant antigens and the different chronic clinical forms of Chagas disease. However, a small proportion of chronic chagasic patients analyzed in this study was positive for this antibody isotype. The findings of this study indicate that the IgM antibodies cannot be used to elucidate the differences in the profile of humoral immune response among chronic chagasic patients with different clinical forms using the CRA and FRA recombinant antigens of T. cruzi. Copyright © 2011 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  6. Blocking variant surface glycoprotein synthesis alters endoplasmic reticulum exit sites/Golgi homeostasis in Trypanosoma brucei.

    Science.gov (United States)

    Ooi, Cher-Pheng; Smith, Terry K; Gluenz, Eva; Wand, Nadina Vasileva; Vaughan, Sue; Rudenko, Gloria

    2018-06-01

    The predominant secretory cargo of bloodstream form Trypanosoma brucei is variant surface glycoprotein (VSG), comprising ~10% total protein and forming a dense protective layer. Blocking VSG translation using Morpholino oligonucleotides triggered a precise pre-cytokinesis arrest. We investigated the effect of blocking VSG synthesis on the secretory pathway. The number of Golgi decreased, particularly in post-mitotic cells, from 3.5 ± 0.6 to 2.0 ± 0.04 per cell. Similarly, the number of endoplasmic reticulum exit sites (ERES) in post-mitotic cells dropped from 3.9 ± 0.6 to 2.7 ± 0.1 eight hours after blocking VSG synthesis. The secretory pathway was still functional in these stalled cells, as monitored using Cathepsin L. Rates of phospholipid and glycosylphosphatidylinositol-anchor biosynthesis remained relatively unaffected, except for the level of sphingomyelin which increased. However, both endoplasmic reticulum and Golgi morphology became distorted, with the Golgi cisternae becoming significantly dilated, particularly at the trans-face. Membrane accumulation in these structures is possibly caused by reduced budding of nascent vesicles due to the drastic reduction in the total amount of secretory cargo, that is, VSG. These data argue that the total flux of secretory cargo impacts upon the biogenesis and maintenance of secretory structures and organelles in T. brucei, including the ERES and Golgi. © 2018 The Authors. Traffic published by John Wiley & Sons Ltd.

  7. A novel ABCG-like transporter of Trypanosoma cruzi is involved in natural resistance to benznidazole

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    Bianca Zingales

    2015-05-01

    Full Text Available Benznidazole (BZ is one of the two drugs used for Chagas disease treatment. Nevertheless therapeutic failures of BZ have been reported, which were mostly attributed to variable drug susceptibility among Trypanosoma cruzi strains. ATP-binding cassette (ABC transporters are involved in a variety of translocation processes and some members have been implicated in drug resistance. Here we report the characterisation of the first T. cruzi ABCG transporter gene, named TcABCG1, which is over-expressed in parasite strains naturally resistant to BZ. Comparison of TcABCG1 gene sequence of two TcI BZ-resistant strains with CL Brener BZ-susceptible strain showed several single nucleotide polymorphisms, which determined 11 amino acid changes. CL Brener transfected with TcI transporter genes showed 40-47% increased resistance to BZ, whereas no statistical significant increment in drug resistance was observed when CL Brener was transfected with the homologous gene. Only in the parasites transfected with TcI genes there was 2-2.6-fold increased abundance of TcABCG1 transporter protein. The analysis in wild type strains also suggests that the level of TcABCG1 transporter is related to BZ natural resistance. The characteristics of untranslated regions of TcABCG1 genes of BZ-susceptible and resistant strains were investigated by computational tools.

  8. Relationship between Trypanosoma brucei rhodesiense genetic diversity and clinical spectrum among sleeping sickness patients in Uganda.

    Science.gov (United States)

    Kato, Charles D; Mugasa, Claire M; Nanteza, Ann; Matovu, Enock; Alibu, Vincent P

    2017-10-27

    Human African trypanosomiasis (HAT) due to Trypanosoma brucei rhodesiense in East and southern Africa is reported to be clinically diverse. We tested the hypothesis that this clinical diversity is associated with a variation in trypanosome genotypes. Trypanosome DNA isolated from HAT patients was genotyped using 7 microsatellite markers directly from blood spotted FTA cards following a whole genome amplification. All markers were polymorphic and identified 17 multi-locus genotypes with 56% of the isolates having replicate genotypes. We did not observe any significant clustering between isolates and bootstrap values across major tree nodes were insignificant. When genotypes were compared among patients with varying clinical presentation or outcome, replicate genotypes were observed at both extremes showing no significant association between genetic diversity and clinical outcome. Our study shows that T. b. rhodesiense isolates are homogeneous within a focus and that observed clinical diversity may not be associated with parasite genetic diversity. Other factors like host genetics and environmental factors might be involved in determining clinical diversity. Our study may be important in designing appropriate control measures that target the parasite.

  9. The Trypanosoma cruzi Protein TcHTE Is Critical for Heme Uptake.

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    Marcelo L Merli

    2016-01-01

    Full Text Available Trypanosoma cruzi, the etiological agent of Chagas' disease, presents nutritional requirements for several metabolites. It requires heme for the biosynthesis of several heme-proteins involved in essential metabolic pathways like mitochondrial cytochromes and respiratory complexes, as well as enzymes involved in the biosynthesis of sterols and unsaturated fatty acids. However, this parasite lacks a complete route for its synthesis. In view of these facts, T. cruzi has to incorporate heme from the environment during its life cycle. In other words, their hosts must supply the heme for heme-protein synthesis. Although the acquisition of heme is a fundamental issue for the parasite's replication and survival, how this cofactor is imported and distributed is poorly understood. In this work, we used different fluorescent heme analogs to explore heme uptake along the different life-cycle stages of T. cruzi, showing that this parasite imports it during its replicative stages: the epimastigote in the insect vector and the intracellular amastigote in the mammalian host. Also, we identified and characterized a T. cruzi protein (TcHTE with 55% of sequence similarity to LHR1 (protein involved in L. amazonensis heme transport, which is located in the flagellar pocket, where the transport of nutrients proceeds in trypanosomatids. We postulate TcHTE as a protein involved in improving the efficiency of the heme uptake or trafficking in T. cruzi.

  10. Anti-Trypanosoma cruzi antibody detection in blood donors in the Southern Brazil

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    A.B. Araújo

    Full Text Available Trypanosoma cruzi, the causal agent of Chagas' Disease, is a widely spread protozoa in America. Blood transfusion is the secondly most important way of acquiring the infection. In blood banks, tests are performed to eliminate potentially infected blood. This study aimed to evaluate the positivity for T. cruzi in blood samples of donor's candidates in Southern Brazil. The study was based on a sampling containing all blood donors of Hemopel - a Pelotas City Blood Center, Rio Grande do Sul State, Brazil, from 2004 to 2005. Serological study was performed using ELISA Chagatest. Sampling containing values ± 20% cut off were evaluated using ELISA Chagatek, ELISA Alka/Adaltis, IHA Chagatest and IIF Imunocruzi. TESA-Blot was used as a confirmatory procedure in situations where blood samples showed conflicting results. From 4,482 samples collected in 2004 and 2005, the reactivity for anti-T. cruzi was 0.96% (43. Among those, 21 cases (0.47% were confirmed as positive - most of them were female, with low school level and averaging 47.2% years old. Interestingly, the blood donors are not aware of being contaminated and this fact makes it difficult for controlling the disease. Chagas' Disease was one of the main reasons for discarding blood bags through serological control in Southern Brazil. Sampling reactivity showed variation among the different techniques used for anti-T. cruzi research. In order to obtaining more secure and conclusive results, more than one diagnostic technique must be used.

  11. Genetic immunization based on the ubiquitin-fusion degradation pathway against Trypanosoma cruzi

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Bin [Department of Microbiology and Immunology, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka 814-0180 (Japan); Department of Parasitology, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582 (Japan); Hiromatsu, Kenji, E-mail: khiromatsu@fukuoka-u.ac.jp [Department of Microbiology and Immunology, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka 814-0180 (Japan); Hisaeda, Hajime; Duan, Xuefeng; Imai, Takashi [Department of Parasitology, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582 (Japan); Murata, Shigeo; Tanaka, Keiji [Department of Molecular Oncology, The Tokyo Metropolitan Institute of Medical Science, Tokyo 113-8613 (Japan); Himeno, Kunisuke [Department of Parasitology, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582 (Japan)

    2010-02-12

    Cytotoxic CD8{sup +} T cells are particularly important to the development of protective immunity against the intracellular protozoan parasite, Trypanosoma cruzi, the etiological agent of Chagas disease. We have developed a new effective strategy of genetic immunization by activating CD8{sup +} T cells through the ubiquitin-fusion degradation (UFD) pathway. We constructed expression plasmids encoding the amastigote surface protein-2 (ASP-2) of T. cruzi. To induce the UFD pathway, a chimeric gene encoding ubiquitin fused to ASP-2 (pUB-ASP-2) was constructed. Mice immunized with pUB-ASP-2 presented lower parasitemia and longer survival period, compared with mice immunized with pASP-2 alone. Depletion of CD8{sup +} T cells abolished protection against T. cruzi in mice immunized with pUB-ASP-2 while depletion of CD4{sup +} T cells did not influence the effective immunity. Mice deficient in LMP2 or LMP7, subunits of immunoproteasomes, were not able to develop protective immunity induced. These results suggest that ubiquitin-fused antigens expressed in antigen-presenting cells were effectively degraded via the UFD pathway, and subsequently activated CD8{sup +} T cells. Consequently, immunization with pUB-ASP-2 was able to induce potent protective immunity against infection of T. cruzi.

  12. Catalase expression impairs oxidative stress-mediated signalling in Trypanosoma cruzi.

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    Freire, Anna Cláudia Guimarães; Alves, Ceres Luciana; Goes, Grazielle Ribeiro; Resende, Bruno Carvalho; Moretti, Nilmar Silvio; Nunes, Vinícius Santana; Aguiar, Pedro Henrique Nascimento; Tahara, Erich Birelli; Franco, Glória Regina; Macedo, Andréa Mara; Pena, Sérgio Danilo Junho; Gadelha, Fernanda Ramos; Guarneri, Alessandra Aparecida; Schenkman, Sergio; Vieira, Leda Quercia; Machado, Carlos Renato

    2017-09-01

    Trypanosoma cruzi is exposed to oxidative stresses during its life cycle, and amongst the strategies employed by this parasite to deal with these situations sits a peculiar trypanothione-dependent antioxidant system. Remarkably, T. cruzi's antioxidant repertoire does not include catalase. In an attempt to shed light on what are the reasons by which this parasite lacks this enzyme, a T. cruzi cell line stably expressing catalase showed an increased resistance to hydrogen peroxide (H2O2) when compared with wild-type cells. Interestingly, preconditioning carried out with low concentrations of H2O2 led untransfected parasites to be as much resistant to this oxidant as cells expressing catalase, but did not induce the same level of increased resistance in the latter ones. Also, presence of catalase decreased trypanothione reductase and increased superoxide dismutase levels in T. cruzi, resulting in higher levels of residual H2O2 after challenge with this oxidant. Although expression of catalase contributed to elevated proliferation rates of T. cruzi in Rhodnius prolixus, it failed to induce a significant increase of parasite virulence in mice. Altogether, these results indicate that the absence of a gene encoding catalase in T. cruzi has played an important role in allowing this parasite to develop a shrill capacity to sense and overcome oxidative stress.

  13. The Chemical Characterization of Nigerian Propolis samples and Their Activity Against Trypanosoma brucei.

    Science.gov (United States)

    Omar, Ruwida; Igoli, John O; Zhang, Tong; Gray, Alexander I; Ebiloma, Godwin U; Clements, Carol J; Fearnley, James; Edrada Ebel, RuAngeli; Paget, Tim; de Koning, Harry P; Watson, David G

    2017-04-19

    Profiling of extracts from twelve propolis samples collected from eight regions in Nigeria was carried out using high performance liquid chromatography (LC) coupled with evaporative light scattering (ELSD), ultraviolet detection (UV) and mass spectrometry (MS), gas chromatography mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). Principal component analysis (PCA) of the processed LC-MS data demonstrated the varying chemical composition of the samples. Most of the samples were active against Trypanosoma b. brucei with the highest activity being in the samples from Southern Nigeria. The more active samples were fractionated in order to isolate the component(s) responsible for their activity using medium pressure liquid chromatography (MPLC). Three xanthones, 1,3,7-trihydroxy-2,8-di-(3-methylbut-2-enyl)xanthone, 1,3,7-trihydroxy-4,8-di-(3-methylbut-2-enyl)xanthone a previously undescribed xanthone and three triterpenes: ambonic acid, mangiferonic acid and a mixture of α-amyrin with mangiferonic acid (1:3) were isolated and characterised by NMR and LC-MS. These compounds all displayed strong inhibitory activity against T.b. brucei but none of them had higher activity than the crude extracts. Partial least squares (PLS) modelling of the anti-trypanosomal activity of the sample extracts using the LC-MS data indicated that high activity in the extracts, as judged from LCMS 2 data, could be correlated to denticulatain isomers in the extracts.

  14. KREX2 is not essential for either procyclic or bloodstream form Trypanosoma brucei.

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    Jason Carnes

    Full Text Available Most mitochondrial mRNAs in Trypanosoma brucei require RNA editing for maturation and translation. The edited RNAs primarily encode proteins of the oxidative phosphorylation system. These parasites undergo extensive changes in energy metabolism between the insect and bloodstream stages which are mirrored by alterations in RNA editing. Two U-specific exonucleases, KREX1 and KREX2, are both present in protein complexes (editosomes that catalyze RNA editing but the relative roles of each protein are not known.The requirement for KREX2 for RNA editing in vivo was assessed in both procyclic (insect and bloodstream form parasites by methods that use homologous recombination for gene elimination. These studies resulted in null mutant cells in which both alleles were eliminated. The viability of these cells demonstrates that KREX2 is not essential in either life cycle stage, despite certain defects in RNA editing in vivo. Furthermore, editosomes isolated from KREX2 null cells require KREX1 for in vitro U-specific exonuclease activity.KREX2 is a U-specific exonuclease that is dispensable for RNA editing in vivo in T. brucei BFs and PFs. This result suggests that the U deletion activity, which is required for RNA editing, is primarily mediated in vivo by KREX1 which is normally found associated with only one type of editosome. The retention of the KREX2 gene implies a non-essential role or a role that is essential in other life cycle stages or conditions.

  15. Natural populations of Trypanosoma cruzi, the agent of Chagas disease, have a complex multiclonal structure

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    Tibayrenc, M.; Ward, P.; Moya, A.; Ayala, F.J.

    1986-01-01

    The authors have studied 15 gene loci coding for enzymes in 121 Trypanosoma cruzi stocks from a wide geographic range - from the US and Mexico to Chile and southern Brazil. T.cruzi is diploid but reproduction is basically clonal, with very little if any sexuality remaining at present. They have identified 43 different clones by their genetic composition; the same genetic clone is often found in very distant places and in diverse hosts. There is much genetic heterogeneity among the different clones, and they cannot be readily classified into a few discrete groups that might represent natural taxa. These findings imply that the biological and medical characteristics need to be ascertained separately for each natural clone. The evidence indicates that clonal evolution is very ancient in T.cruzi. The authors propose two alternative hypotheses concerning the relationship between the biochemical diversity and the heterogeneity in other biological and medical characteristics of T. cruzi. One hypothesis is that the degree of diversity between strains simply reflects the time elapsed since their last common ancestor. The second hypothesis is that biological and medical heterogeneity is recent and reflects adaptation to different transmission cycles. A decision between the two hypotheses can be reached with appropriate studies, with important medical consequences.

  16. Heme-induced Trypanosoma cruzi proliferation is mediated by CaM kinase II

    International Nuclear Information System (INIS)

    Souza, C.F.; Carneiro, A.B.; Silveira, A.B.; Laranja, G.A.T.; Silva-Neto, M.A.C.; Costa, S.C. Goncalves da; Paes, M.C.

    2009-01-01

    Trypanosoma cruzi, the etiologic agent of Chagas disease, is transmitted through triatomine vectors during their blood-meal on vertebrate hosts. These hematophagous insects usually ingest approximately 10 mM of heme bound to hemoglobin in a single meal. Blood forms of the parasite are transformed into epimastigotes in the crop which initiates a few hours after parasite ingestion. In a previous work, we investigated the role of heme in parasite cell proliferation and showed that the addition of heme significantly increased parasite proliferation in a dose-dependent manner . To investigate whether the heme effect is mediated by protein kinase signalling pathways, parasite proliferation was evaluated in the presence of several protein kinase (PK) inhibitors. We found that only KN-93, a classical inhibitor of calcium-calmodulin-dependent kinases (CaMKs), blocked heme-induced cell proliferation. KN-92, an inactive analogue of KN-93, was not able to block this effect. A T. cruzi CaMKII homologue is most likely the main enzyme involved in this process since parasite proliferation was also blocked when Myr-AIP, an inhibitory peptide for mammalian CaMKII, was included in the cell proliferation assay. Moreover, CaMK activity increased in parasite cells with the addition of heme as shown by immunological and biochemical assays. In conclusion, the present results are the first strong indications that CaMKII is involved in the heme-induced cell signalling pathway that mediates parasite proliferation.

  17. Large-scale conformational changes of Trypanosoma cruzi proline racemase predicted by accelerated molecular dynamics simulation.

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    César Augusto F de Oliveira

    2011-10-01

    Full Text Available Chagas' disease, caused by the protozoan parasite Trypanosoma cruzi (T. cruzi, is a life-threatening illness affecting 11-18 million people. Currently available treatments are limited, with unacceptable efficacy and safety profiles. Recent studies have revealed an essential T. cruzi proline racemase enzyme (TcPR as an attractive candidate for improved chemotherapeutic intervention. Conformational changes associated with substrate binding to TcPR are believed to expose critical residues that elicit a host mitogenic B-cell response, a process contributing to parasite persistence and immune system evasion. Characterization of the conformational states of TcPR requires access to long-time-scale motions that are currently inaccessible by standard molecular dynamics simulations. Here we describe advanced accelerated molecular dynamics that extend the effective simulation time and capture large-scale motions of functional relevance. Conservation and fragment mapping analyses identified potential conformational epitopes located in the vicinity of newly identified transient binding pockets. The newly identified open TcPR conformations revealed by this study along with knowledge of the closed to open interconversion mechanism advances our understanding of TcPR function. The results and the strategy adopted in this work constitute an important step toward the rationalization of the molecular basis behind the mitogenic B-cell response of TcPR and provide new insights for future structure-based drug discovery.

  18. Interactions among Trypanosoma brucei RAD51 paralogues in DNA repair and antigenic variation

    Science.gov (United States)

    Dobson, Rachel; Stockdale, Christopher; Lapsley, Craig; Wilkes, Jonathan; McCulloch, Richard

    2011-01-01

    Homologous recombination in Trypanosoma brucei is used for moving variant surface glycoprotein (VSG) genes into expression sites during immune evasion by antigenic variation. A major route for such VSG switching is gene conversion reactions in which RAD51, a universally conserved recombinase, catalyses homology-directed strand exchange. In any eukaryote, RAD51-directed strand exchange in vivo is mediated by further factors, including RAD51-related proteins termed Rad51 paralogues. These appear to be ubiquitously conserved, although their detailed roles in recombination remain unclear. In T. brucei, four putative RAD51 paralogue genes have been identified by sequence homology. Here we show that all four RAD51 paralogues act in DNA repair, recombination and RAD51 subnuclear dynamics, though not equivalently, while mutation of only one RAD51 paralogue gene significantly impedes VSG switching. We also show that the T. brucei RAD51 paralogues interact, and that the complexes they form may explain the distinct phenotypes of the mutants as well as observed expression interdependency. Finally, we document the Rad51 paralogues that are encoded by a wide range of protists, demonstrating that the Rad51 paralogue repertoire in T. brucei is unusually large among microbial eukaryotes and that one member of the protein family corresponds with a key, conserved eukaryotic Rad51 paralogue. PMID:21615552

  19. Crystallization and preliminary X-ray analysis of aspartate transcarbamoylase from the parasitic protist Trypanosoma cruzi

    International Nuclear Information System (INIS)

    Matoba, Kazuaki; Nara, Takeshi; Aoki, Takashi; Honma, Teruki; Tanaka, Akiko; Inoue, Masayuki; Matsuoka, Shigeru; Inaoka, Daniel Ken; Kita, Kiyoshi; Harada, Shigeharu

    2009-01-01

    Aspartate transcarbamoylase, the second enzyme of the de novo pyrimidine-biosynthetic pathway, from T. cruzi has been purified and crystallized for X-ray structure analysis. Aspartate transcarbamoylase (ATCase), the second enzyme of the de novo pyrimidine-biosynthetic pathway, catalyzes the production of carbamoyl aspartate from carbamoyl phosphate and l-aspartate. In contrast to Escherichia coli ATCase and eukaryotic CAD multifunctional fusion enzymes, Trypanosoma cruzi ATCase lacks regulatory subunits and is not part of the multifunctional fusion enzyme. Recombinant T. cruzi ATCase expressed in E. coli was purified and crystallized in a ligand-free form and in a complex with carbamoyl phosphate at 277 K by the sitting-drop vapour-diffusion technique using polyethylene glycol 3350 as a precipitant. Ligand-free crystals (space group P1, unit-cell parameters a = 78.42, b = 79.28, c = 92.02 Å, α = 69.56, β = 82.90, γ = 63.25°) diffracted X-rays to 2.8 Å resolution, while those cocrystallized with carbamoyl phosphate (space group P2 1 , unit-cell parameters a = 88.41, b = 158.38, c = 89.00 Å, β = 119.66°) diffracted to 1.6 Å resolution. The presence of two homotrimers in the asymmetric unit (38 kDa × 6) gives V M values of 2.3 and 2.5 Å 3 Da −1 for the P1 and P2 1 crystal forms, respectively

  20. Biochemical behavior of Trypanosoma cruzi strains isolated from mice submitted to specific chemotherapy

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    Jesila Pinto M. Marretto

    1994-12-01

    Full Text Available To investigate the influence of chemotherapy on the biochemical beha vior of Trypanosoma cruzi strains, three groups of mice were infected with one of three strains of T. cruzi of different biological and isoenzymic patterns (Peruvian, 21 SF and Colombian strains. Each group was subdivided into subgroups: 1 - treated with nifurtimox; 2 - treated with benznidazole and 3 - untreated infected controls. At the end of treatment, that lasted for 90 days, xenodiagnosis, sub inoculation of blood into new born mice and haemoculture were performed as tests of cure. From the positive tests, 22 samples of T. cruzi were isolated from all subgroups. Electrophoretic analysis of the isoenzymes PGM, GP1, ALAT and AS AT failed to show any difference between parasite strains isolated from treated and untreated mice, which indicates that no detectable clonal selection or parasite genetic markers alterations concerning the isoenzymes analysed have been determined by treatment with drugs of recognized antiparasitic effect, suggesting stability of the phenotypic characteristics of the three biological types of T. cruzi strains.

  1. The adipocyte as an important target cell for Trypanosoma cruzi infection.

    Science.gov (United States)

    Combs, Terry P; Nagajyothi; Mukherjee, Shankar; de Almeida, Cecilia J G; Jelicks, Linda A; Schubert, William; Lin, Ying; Jayabalan, David S; Zhao, Dazhi; Braunstein, Vicki L; Landskroner-Eiger, Shira; Cordero, Aisha; Factor, Stephen M; Weiss, Louis M; Lisanti, Michael P; Tanowitz, Herbert B; Scherer, Philipp E

    2005-06-24

    Adipose tissue plays an active role in normal metabolic homeostasis as well as in the development of human disease. Beyond its obvious role as a depot for triglycerides, adipose tissue controls energy expenditure through secretion of several factors. Little attention has been given to the role of adipocytes in the pathogenesis of Chagas disease and the associated metabolic alterations. Our previous studies have indicated that hyperglycemia significantly increases parasitemia and mortality in mice infected with Trypanosoma cruzi. We determined the consequences of adipocyte infection in vitro and in vivo. Cultured 3T3-L1 adipocytes can be infected with high efficiency. Electron micrographs of infected cells revealed a large number of intracellular parasites that cluster around lipid droplets. Furthermore, infected adipocytes exhibited changes in expression levels of a number of different adipocyte-specific or adipocyte-enriched proteins. The adipocyte is therefore an important target cell during acute Chagas disease. Infection of adipocytes by T. cruzi profoundly influences the pattern of adipokines. During chronic infection, adipocytes may represent an important long-term reservoir for parasites from which relapse of infection can occur. We have demonstrated that acute infection has a unique metabolic profile with a high degree of local inflammation in adipose tissue, hypoadiponectinemia, hypoglycemia, and hypoinsulinemia but with relatively normal glucose disposal during an oral glucose tolerance test.

  2. Trypanosoma cruzi infection in Didelphis marsupialis in Santa Catarina and Arvoredo Islands, southern Brazil

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    Grisard Edmundo C

    2000-01-01

    Full Text Available Between 1984 and 1993 the prevalence of the Trypanosoma cruzi infection in opossums (Didelphis marsupialis was studied in Santa Catarina and Arvoredo Islands, State of Santa Catarina, Brazil. The association of the triatomine bug Panstrongylus megistus with opossums nests and the infection rate of these triatomines by T. cruzi was also studied. Thirteen different locations were studied in Santa Catarina Island (SCI, in which 137 D. marsupialis were collected. Sixty two opossums were collected at the Arvoredo Island (AI, located 12 miles north from SCI. All captured animals were submitted to parasitological examinations that revealed the presence of T. cruzi in 21.9% of the opossums captured in SCI and 45.2% among opossums captured in the AI. The presence of P. megistus was detected in most of the D. marsupialis nests collected in the SCI, however, in the non-inhabited AI only eight triatomines were collected during the whole study. The presence of T. cruzi-infected D. marsupialis associated with P. megistus in human dwellings in the SCI, and the high infection rate of D. marsupilais by T. cruzi in the absence of a high vector density are discussed.

  3. Trypanosoma cruzi: Correlations of Biological Aspects of the Life Cycle in Mice and Triatomines

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    Lima Valdirene S

    1999-01-01

    Full Text Available The infection pattern in Swiss mice and Triatomine bugs (Rhodnius neglectus of eleven clones and the original stock of a Trypanosoma cruzi isolate, derived from a naturally infected Didelphis marsupialis, were biochemically and biologically characterized. The clones and the original isolate were in the same zymodeme (Z1 except that two clones were found to be in zymodeme 2 when tested with G6PDH. Although infective, neither the original isolate nor the clones were highly virulent for the mice and lesions were only observed in mice infected with the original stock and one of the clones (F8. All clones and the original isolate infected bugs well while only the original isolate and clones E2 and F3 yielded high metacyclogenesis rates. An observed correlation between absence of lesions in the mammal host and high metacyclogenesis rates in the invertebrate host suggest a evolutionary trade off i.e. a fitness increase in one trait which is accompanied by a fitness reduction in a different one. Our results suggest that in a species as heterogeneous as T. cruzi, a cooperation effect among the subpopulations should be considered.

  4. Experimental transmission of Trypanosoma cruzi through the genitalia of albino mice

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    Leidi Herrera

    2001-07-01

    Full Text Available Trypanosoma cruzi is usually transmitted by contact with the excreta of infected Triatominae; among non-vectorial infections, direct transmission through coitus has been proposed. We investigated this possibility by instilling, through the external meatus of the vagina and the penis of previously anesthetized NMRI albino mice, blood of mice infected with strains isolated from Didelphis marsupialis (opossum, strain CO57, Rattus rattus (rat, strain CO22 and human (strain EP. Some animals were allowed to copulate the same day of the instillation. In other experiments, the strains were inoculated in the scrotum. To determine the effect of immunosuppression, some mice were treated with cyclophosphamide 30 days post-instillation. Controls were instilled orally and ocularly. Vaginal instillation with strain CO22 produced systemic infection with tropism to the heart, skeletal muscle, skin, duodenum, pancreas, ovary and sternum. Scrotal inoculation with strain EP likewise invaded liver, spleen, lung, lymph nodes and urogenital organs; while strain CO57 invaded skeletal and cardiac muscle, pancreas, testis, and vas deferens. Penile infection with strain CO22 was detected by xenodiagnosis. Immunosuppression did not increase parasitemia of vaginally infected mice or controls. Mating did not produce infection. Our results show that contact of blood trypomastigotes of T. cruzi with genital mucosa can produce blood and tissue infections. These results are discussed in relation to reports of frequent experimental tropism of T. cruzi toward urogenital organs.

  5. Trypanosoma (Megatrypanum saloboense n. sp. (Kinetoplastida: Trypanosomatidae parasite of Monodelphis emiliae (Marsupiala: Didelphidae from Amazonian Brazil

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    Lainson R.

    2008-06-01

    Full Text Available Trypanosoma (Megatrypanum saloboense n. sp., is described in the Brazilian opossum Monodelphis emiliae (Thomas, 1912 from primary forest in the Salobo area of the Serra dos Carajás (6° S, 50° 18′ W Pará State, North Brazil. Two morphologically different trypomastigotes were noted. Slender forms, regarded as immature parasites, have a poorly developed undulating membrane adhering closely to the body: large, broad forms with a well developed membrane are considered to be the mature trypomastigotes and have a mean total length of 71.2 μm (62.4-76.2 and a width of 6.1 (5.0-8.0. Infections studied in two opossums were of very low parasitaemia. The large size of T. (M. saloboense readily distinguishes it from the two previously described members of the subgenus Megatrypanum of neotropical marsupials, T. (M. freitasi Régo et al., 1957 of Didelphis azarae and D. marsupialis, and T. (M. samueli Mello, 1977 of Monodelphis domesticus, which measure only 49.0-51.5 μm and 42.4 μm respectively. No infections were obtained in hamsters inoculated with triturated liver and spleen from one infected M. emiliae, or in laboratory mice inoculated with epimastigotes from a blood-agar culture. No division stages could be detected in the internal organs or the peripheral blood.

  6. Histopathological study of experimental and natural infections by Trypanosoma cruzi in Didelphis marsupialis

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    João Carlos Araujo Carreira

    1996-10-01

    Full Text Available Didelphis marsupialis, the most important sylvatic reservoir of Trypanosoma cruzi, can also maintain in their anal scent glands the multiplicative forms only described in the intestinal tract of triatomine bugs. A study of 21 experimentally and 10 naturally infected opossums with T. cruzi was undertaken in order to establish the histopathological pattern under different conditions. Our results showed that the inflammation was predominantly lymphomacrophagic and more severe in the naturally infected animals but never as intense as those described in Chagas' disease or in other animal models. The parasitism in both groups was always mild with very scarce amastigote nests in the tissues. In the experimentally infected animals, the inflammation was directly related to the presence of amastigotes nests. Four 24 days-old animals, still in embryonic stage, showed multiple amastigotes nests and moderate inflammatory reactions, but even so they survived longer and presented less severe lesions than experimentally infected adult mice. Parasites were found in smooth, cardiac and/or predominantly striated muscles, as well as in nerve cells. Differing from the experimentally infected opossums parasitism in the naturally infected animals predominated in the heart, esophagus and stomach. Parasitism of the scent glands did not affect the histopathological pattern observed in extraglandular tissues.

  7. CD8+ T Cell-Mediated Immunity during Trypanosoma cruzi Infection: A Path for Vaccine Development?

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    Fernando dos Santos Virgilio

    2014-01-01

    Full Text Available MHC-restricted CD8+ T cells are important during infection with the intracellular protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Experimental studies performed in the past 25 years have elucidated a number of features related to the immune response mediated by these T cells, which are important for establishing the parasite/host equilibrium leading to chronic infection. CD8+ T cells are specific for highly immunodominant antigens expressed by members of the trans-sialidase family. After infection, their activation is delayed, and the cells display a high proliferative activity associated with high apoptotic rates. Although they participate in parasite control and elimination, they are unable to clear the infection due to their low fitness, allowing the parasite to establish the chronic phase when these cells then play an active role in the induction of heart immunopathology. Vaccination with a number of subunit recombinant vaccines aimed at eliciting specific CD8+ T cells can reverse this path, thereby generating a productive immune response that will lead to the control of infection, reduction of symptoms, and reduction of disease transmission. Due to these attributes, activation of CD8+ T lymphocytes may constitute a path for the development of a veterinarian or human vaccine.

  8. [Vectorial and congenital transmission of Trypanosoma cruzi in Las Lomitas, Formosa].

    Science.gov (United States)

    Sosa-Estani, Sergio; Dri, Lucía; Touris, Cecilia; Abalde, Sergio; Dell'arciprete, Ana; Braunstein, Jose

    2009-01-01

    Chagas disease, caused by Trypanosoma cruzi, is a major cause of morbidity and mortality in Latin America. The objective of this study was to describe the rate of infestation in four aboriginal communities in Las Lomitas (Great Chaco Region), Formosa, Argentina; the rate of infection in children residing in these communities, in blood donors and in pregnant women who received care at the Hospital Las Lomitas, as well as the rate of congenital infection in children born to women infected during the study period. The rate of infestation of 172 households evaluated in 2006 reached 32%. Prevalence of infection among 445 people was 17.5% and in children under 5 years old it was 8.6%. The rate of infection reached 18.6% in blood donors and 29.1% in pregnant women. The rate of infection among 47 children born to infected women, and living in residences under vectorial surveillance was 17.0%. These infections were considered as congenital. This study showed indexes compatible with active vectorial transmission at the beginning. After vectorial control with insecticides the infestation rate has been reduced to 3.3%. The local health system has introduced high impact procedures of primary and secondary prevention in order to prevent new cases and to treat infected people.

  9. PREDICTORS OF TRYPANOSOMA LEWISI IN RATTUS NORVEGICUS FROM DURBAN, SOUTH AFRICA.

    Science.gov (United States)

    Archer, Colleen Edith; Schoeman, M Corrie; Appleton, Christopher Charles; Mukaratirwa, Samson; Hope, Karen J; Matthews, Glenda Beverly

    2018-03-16

    This study investigated associations between Trypanosoma lewisi; Xenopsylla cheopis, a common cyclical vector of T. lewisi; Polyplax spinulosa, a reported mechanical vector; and Laelaps ecidnina and L. lamborni, two rodent mites of Rattus norvegicus in Durban. Three hundred and seventy nine R. norvegicus were live-trapped at 48 sites in 4 locality types of Durban during a one year period. Rats were euthanized, cardiac blood was taken to check for hemoparasites and ectoparasites were removed for identification. Parasite species richness was higher in pups (2.11) and juveniles (1.02) than adults (0.87). Most rats in the study harbored 1 or 2 of the 5 parasites examined. Rats with trypanosomes and fleas were more prevalent in the city center and harbor, and juveniles were most affected. Rats with lice were more prevalent in informal settlements and urban/peri-urban areas and pups had the highest infestations. There was a significant positive association between rats with fleas and trypanosomes and a negative association between rats with lice and trypanosomes. Location and rat age were significant predictors of T. lewisi, X. cheopis and P. spinulosa. Mites showed no strong associations with trypanosomes. Ectoparasite associations are possibly habitat and life-cycle related. We conclude that Durban's city center, which offers rats harborage, an unsanitary environment and availability of food, is a high transmission area for fleas and trypanosomes, and consequently, a potential public health risk.

  10. Trypanosoma melophagium from the sheep ked Melophagus ovinus on the island of St Kilda.

    Science.gov (United States)

    Gibson, W; Pilkington, J G; Pemberton, J M

    2010-10-01

    SUMMARYThe sheep ked has been largely eradicated in the UK but persists in the feral Soay sheep of St Kilda in the Outer Hebrides. Sheep keds transmit Trypanosoma melophagium, but parasitaemias are typically cryptic and this trypanosome