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Sample records for da leishmania amazonensis

  1. The activity of azithromycin against Leishmania (Viannia) braziliensis and Leishmania (Leishmania) amazonensis in the golden hamster model / A atividade da azitromicina contra a Leishmania (Viannia) braziliensis e a Leishmania (Leishmania) amazonensis no modelo golden hamster

    Scientific Electronic Library Online (English)

    Ángel, Sinagra; Concepción, Luna; David, Abraham; Maria del Carmen, Iannella; Adelina, Riarte; Alejandro J., Krolewiecki.

    2007-12-01

    Full Text Available Novas alternativas terapêuticas contra a leishmaniose são ainda uma prioridade. A atividade da azitromicina contra a Leishmania (Leishmania) major foi anteriormente demonstrada. Diferentes respostas entre as espécies de Leishmania fazem com que um screening de drogas específicas para espécies seja n [...] ecessário. A atividade da azitromicina contra a Leishmania (Viannia) braziliensis e a Leishmania (Leishmania) amazonensis foi avaliada em Golden hamsters infectados a través de injeções de promastigotas metacíclicas e comparando com controles sem tratamento e animais tratados com antimoniato de N-metil-glucamina. Foram analisadas a espessura da pata, a cultura das lesões e disseminação para órgãos internos. A azitromicina oral em dose de 450mg/kg não teve atividade contra a infecção por Leishmania ( Leishmania) amazonensis. Para infecções devidas à Leishmania (Viannia) braziliensis, a azitromicina teve uma atividade significativa em relação aos controles sem tratamento, mas foi inferior ao antimoniato de N-metil-glucamina quanto ao controle do tamanho das lesões. Nenhuma das drogas conseguiu eliminar totalmente os parasitos das lesões. Foi concluído que a azitromicina tem atividade contra Leishmania (Viannia) braziliensis, mas não tem atividade contra Leishmania (Leishmania) amazonensis neste modelo. Abstract in english New therapeutic alternatives against leishmaniasis remain a priority. The activity of azithromycin against Leishmania (Leishmania) major has been previously demonstrated. Different responses among species of Leishmania make species-specific drug screening necessary. The activity of azithromycin agai [...] nst Leishmania (Viannia) braziliensis and Leishmania (Leishmania) amazonensis was evaluated in golden hamsters infected through footpad injections of metacyclic promastigotes, and compared with untreated controls and animals treated with meglumine antimoniate. Footpad thickness, lesion cultures and dissemination sites were analyzed. Treatment of golden hamsters with oral azithromycin at 450mg/kg had no activity against infections with Leishmania (Leishmania) amazonensis. For infections due to Leishmania (Viannia) braziliensis, azithromycin demonstrated significant activity relative to untreated controls, but inferior to meglumine antimoniate, for controlling lesion size. Neither drug was able to totally eliminate parasites from the lesions. It was concluded that azithromycin has activity against Leishmania (Viannia) braziliensis but not against Leishmania (Leishmania) amazonensis in this model.

  2. The activity of azithromycin against Leishmania (Viannia braziliensis and Leishmania (Leishmania amazonensis in the golden hamster model A atividade da azitromicina contra a Leishmania (Viannia braziliensis e a Leishmania (Leishmania amazonensis no modelo golden hamster

    Directory of Open Access Journals (Sweden)

    Ángel Sinagra

    2007-12-01

    Full Text Available New therapeutic alternatives against leishmaniasis remain a priority. The activity of azithromycin against Leishmania (Leishmania major has been previously demonstrated. Different responses among species of Leishmania make species-specific drug screening necessary. The activity of azithromycin against Leishmania (Viannia braziliensis and Leishmania (Leishmania amazonensis was evaluated in golden hamsters infected through footpad injections of metacyclic promastigotes, and compared with untreated controls and animals treated with meglumine antimoniate. Footpad thickness, lesion cultures and dissemination sites were analyzed. Treatment of golden hamsters with oral azithromycin at 450mg/kg had no activity against infections with Leishmania (Leishmania amazonensis. For infections due to Leishmania (Viannia braziliensis, azithromycin demonstrated significant activity relative to untreated controls, but inferior to meglumine antimoniate, for controlling lesion size. Neither drug was able to totally eliminate parasites from the lesions. It was concluded that azithromycin has activity against Leishmania (Viannia braziliensis but not against Leishmania (Leishmania amazonensis in this model.Novas alternativas terapêuticas contra a leishmaniose são ainda uma prioridade. A atividade da azitromicina contra a Leishmania (Leishmania major foi anteriormente demonstrada. Diferentes respostas entre as espécies de Leishmania fazem com que um screening de drogas específicas para espécies seja necessário. A atividade da azitromicina contra a Leishmania (Viannia braziliensis e a Leishmania (Leishmania amazonensis foi avaliada em Golden hamsters infectados a través de injeções de promastigotas metacíclicas e comparando com controles sem tratamento e animais tratados com antimoniato de N-metil-glucamina. Foram analisadas a espessura da pata, a cultura das lesões e disseminação para órgãos internos. A azitromicina oral em dose de 450mg/kg não teve atividade contra a infecção por Leishmania ( Leishmania amazonensis. Para infecções devidas à Leishmania (Viannia braziliensis, a azitromicina teve uma atividade significativa em relação aos controles sem tratamento, mas foi inferior ao antimoniato de N-metil-glucamina quanto ao controle do tamanho das lesões. Nenhuma das drogas conseguiu eliminar totalmente os parasitos das lesões. Foi concluído que a azitromicina tem atividade contra Leishmania (Viannia braziliensis, mas não tem atividade contra Leishmania (Leishmania amazonensis neste modelo.

  3. Clonaje de la proteína de choque térmico de 20 kDa de Leishmania amazonensis Cloning of 20 kDa heat shock protein of Leishmania amazonensis

    Directory of Open Access Journals (Sweden)

    Ana Margarita Montalvo Álvarez

    2009-08-01

    Full Text Available INTRODUCCIÓN: la inducción de las proteínas de choque térmico constituyen un mecanismo homeostático que protege a las células del efecto destructivo del calor u otras condiciones de estrés ambiental, paralelamente, ellas cumplen importantes funciones celulares. La proteína de choque térmico de 20 kDa se reportó recientemente en Leishmania amazonensis. OBJETIVO: describir la metodología utilizada para realizar el clonaje de las proteínas de choque térmico, lo que permitió acometer estudios de algunas propiedades biológicas. MÉTODOS: la región codificante del gen hsp20 se amplificó mediante la reacción en cadena de la polimerasa con cebadores adecuados. El producto amplificado se clonó inicialmente en el vector pCR2.1 (Invitrogen y después en el vector de expresión en procariotas pET-28b (Novagen, para obtener proteína recombinante. De manera paralela, el mismo fragmento se clonó en el vector de expresión en eucariotas pcDNA3 (Invitrogen para obtener un posible preparado vacunal de ADN. Se realizó la secuenciación nucleotídica de los clones obtenidos, con la finalidad de verificar su fidelidad. RESULTADOS: se obtuvieron plásmidos recombinantes que codifican la HSP20 de Leishmania, y permiten la obtención de proteína recombinante y de ADN en forma masiva. CONCLUSIONES: ambos plásmidos fueron útiles para estudiar algunas de las propiedades biológicas de esta proteína. Este acercamiento puede ser de interés en otros trabajos de esta índole y constituir una guía metodológica.INTRODUCTION: the induction of heat shock proteins is a homeostatic mechanism that protects cells from the deleterious effects of thermal and other environmental stresses. In addition, they have important cell functions. The 20kDa heat shock protein in Leishmania amazonensis was recently reported. OBJECTIVE: to describe the methodology used for cloning of heat shock proteins, which allowed the study of some biological properties. METHODS: the hsp20 gene coding region was amplified by polymerase chain reaction using adequate primers. The amplified product was initially cloned in pCR2.1 vector (Invitrogen and then in pET-28b vector (Novagen, to obtain recombinant protein. The same fragment was cloned also in the eukariote expression vector pcDNA3 (Invitrogen. The nucleotidic sequencing of the different clones was made, in order to verify their fidelity. RESULTS: the recombinant plasmids that encode HSP20 protein in Leishmania and allow obtaining massively recombinant protein and DNA were produced. CONCLUSIONS: both plasmids were useful to study some of the biological properties of this protein. This approach could be useful for similar research and represent a suitable methodological guideline.

  4. Clonaje de la proteína de choque térmico de 20 kDa de Leishmania amazonensis / Cloning of 20 kDa heat shock protein of Leishmania amazonensis

    Scientific Electronic Library Online (English)

    Ana Margarita, Montalvo Álvarez; Cristina, Folgueira Fernández; José María, Requena Rolanía.

    2009-08-01

    Full Text Available INTRODUCCIÓN: la inducción de las proteínas de choque térmico constituyen un mecanismo homeostático que protege a las células del efecto destructivo del calor u otras condiciones de estrés ambiental, paralelamente, ellas cumplen importantes funciones celulares. La proteína de choque térmico de 20 kD [...] a se reportó recientemente en Leishmania amazonensis. OBJETIVO: describir la metodología utilizada para realizar el clonaje de las proteínas de choque térmico, lo que permitió acometer estudios de algunas propiedades biológicas. MÉTODOS: la región codificante del gen hsp20 se amplificó mediante la reacción en cadena de la polimerasa con cebadores adecuados. El producto amplificado se clonó inicialmente en el vector pCR2.1 (Invitrogen) y después en el vector de expresión en procariotas pET-28b (Novagen), para obtener proteína recombinante. De manera paralela, el mismo fragmento se clonó en el vector de expresión en eucariotas pcDNA3 (Invitrogen) para obtener un posible preparado vacunal de ADN. Se realizó la secuenciación nucleotídica de los clones obtenidos, con la finalidad de verificar su fidelidad. RESULTADOS: se obtuvieron plásmidos recombinantes que codifican la HSP20 de Leishmania, y permiten la obtención de proteína recombinante y de ADN en forma masiva. CONCLUSIONES: ambos plásmidos fueron útiles para estudiar algunas de las propiedades biológicas de esta proteína. Este acercamiento puede ser de interés en otros trabajos de esta índole y constituir una guía metodológica. Abstract in english INTRODUCTION: the induction of heat shock proteins is a homeostatic mechanism that protects cells from the deleterious effects of thermal and other environmental stresses. In addition, they have important cell functions. The 20kDa heat shock protein in Leishmania amazonensis was recently reported. O [...] BJECTIVE: to describe the methodology used for cloning of heat shock proteins, which allowed the study of some biological properties. METHODS: the hsp20 gene coding region was amplified by polymerase chain reaction using adequate primers. The amplified product was initially cloned in pCR2.1 vector (Invitrogen) and then in pET-28b vector (Novagen), to obtain recombinant protein. The same fragment was cloned also in the eukariote expression vector pcDNA3 (Invitrogen). The nucleotidic sequencing of the different clones was made, in order to verify their fidelity. RESULTS: the recombinant plasmids that encode HSP20 protein in Leishmania and allow obtaining massively recombinant protein and DNA were produced. CONCLUSIONS: both plasmids were useful to study some of the biological properties of this protein. This approach could be useful for similar research and represent a suitable methodological guideline.

  5. Subcellular localization of an intracellular serine protease of 68 kDa in Leishmania (Leishmania amazonensis promastigotes

    Directory of Open Access Journals (Sweden)

    José Andrés Morgado-Díaz

    2005-07-01

    Full Text Available Here we report the subcellular localization of an intracellular serine protease of 68 kDa in axenic promastigotes of Leishmania (Leishmania amazonensis, using subcellular fractionation, enzymatic assays, immunoblotting, and immunocytochemistry. All fractions were evaluated by transmission electron microscopy and the serine protease activity was measured during the cell fractionation procedure using a-N-r-tosyl-L-arginine methyl ester (L-TAME as substrate, phenylmethylsulphone fluoride (PMSF and L-1-tosylamino-2-phenylethylchloromethylketone (TPCK as specific inhibitors. The enzymatic activity was detected mainly in a membranous vesicular fraction (6.5-fold enrichment relative to the whole homogenate, but also in a crude plasma membrane fraction (2.0-fold. Analysis by SDS-PAGE gelatin under reducing conditions demonstrated that the major proteolytic activity was found in a 68 kDa protein in all fractions studied. A protein with identical molecular weight was also recognized in immunoblots by a polyclonal antibody against serine protease (anti-SP, with higher immunoreactivity in the vesicular fraction. Electron microscopic immunolocalization using the same polyclonal antibody showed the enzyme present at the cell surface, as well as in cytoplasmic membranous compartments of the parasite. Our findings indicate that the internal location of this serine protease in L. amazonensis is mainly restricted to the membranes of intracellular compartments resembling endocytic/exocytic elements.

  6. Role of Leishmania (Leishmania) amazonensis amastigote glycosphingolipids in macrophage infectivity

    Scientific Electronic Library Online (English)

    A.K., Tanaka; P.A.J., Gorin; H.K., Takahashi; A.H., Straus.

    2007-06-01

    Full Text Available The role of glycosphingolipids (GSLs) present in amastigote forms of Leishmania (Leishmania) amazonensis during infection of macrophages was analyzed, with particular emphasis on GSLs presenting the terminal Galpß1-3Galpa disaccharide. Macrophage invasion by L. (L.) amazonensis amastigotes was reduc [...] ed by 37% when the disaccharide Galpß1-3Galp (1 mM) was added to the culture medium. The putative macrophage receptor/lectin for ß-Gal-globotriaosylceramide (Galpß1-3Galpa1-4Galpß1-4Glc pß1-1Cer) and other structurally related GSLs from L. (L.) amazonensis amastigotes were analyzed by micelles and parasite binding assay to peritoneal macrophage proteins fractionated by SDS-PAGE under nonreducing conditions. Micelles containing purified amastigote GSLs or a suspention of L. (L.) amazonensis amastigotes fixed with 2% formaldehyde were incubated with nitrocellulose membrane containing the macrophage proteins transferred by Western blotting. Binding of micelles containing purified GSLs from amastigote forms or fixed L. (L.) amazonensis amastigotes to nitrocellulose membrane was probed using monoclonal antibody ST-3, which recognizes the glycoepitope Galpß1-3Galpa1-R present either in the micelle preparation or on the amastigote surface. Macrophage protein with molecular mass ~30 kDa bound the amastigote GSL and appeared to be a doublet on electrophoresis. The specificity of this interaction was confirmed using fixed L. (L.) chagasi amastigotes, which do not express GSLs such as ß-Galp-globotriaosylceramides, and which do not bind to 30-kDa protein.

  7. The Comparative Genomics and Phylogenomics of Leishmania amazonensis Parasite

    OpenAIRE

    Diogo A Tschoeke; Nunes, Gisele L; Rodrigo Jardim; Joana Lima; Aline SR Dumaresq; Gomes, Monete R; Leandro de Mattos Pereira; Loureiro, Daniel R; Patricia H Stoco; Herbert Leonel de Matos Guedes; Antonio Basilio de Miranda; Jeronimo Ruiz; André Pitaluga; Floriano P Silva Jr; Christian M Probst

    2014-01-01

    Leishmaniasis is an infectious disease caused by Leishmania species. Leishmania amazonensis is a New World Leishmania species belonging to the Mexicana complex, which is able to cause all types of leishmaniasis infections. The L. amazonensis reference strain MHOM/BR/1973/M2269 was sequenced identifying 8,802 codifying sequences (CDS), most of them of hypothetical function. Comparative analysis using six Leishmania species showed a core set of 7,016 orthologs. L. amazonensis and Leishmania mex...

  8. In vivo antileishmanial efficacy of miltefosine against Leishmania (Leishmania) amazonensis.

    Science.gov (United States)

    García Bustos, María F; Barrio, Alejandra; Prieto, Gabriela G; de Raspi, Emma M; Cimino, Rubén O; Cardozo, Rubén M; Parada, Luis A; Yeo, Matthew; Soto, Jaime; Uncos, Delfor A; Parodi, Cecilia; Basombrío, Miguel A

    2014-12-01

    Leishmaniasis, a disease caused by parasites of the Leishmania genus, constitutes a significant health and social problem in many countries and is increasing worldwide. The conventional treatment, meglumine antimoniate (MA), presents numerous disadvantages, including invasiveness, toxicity, and frequent therapeutic failure, justifying the attempts at finding alternatives to the first-line therapy. We have studied the comparative long-term efficacy of MA against miltefosine (MF) in Leishmania infection in experimental mice. The criteria for efficacy evaluation were footpad lesion size, anti-Leishmania antibodies level, histopathology of the site of inoculation (right footpad, RFP), splenic index (SI), and the presence of parasites in RFP, spleen, and liver, determined by polymerase chain reaction (PCR). Swiss mice, infected with Leishmania (Leishmania) amazonensis were treated, at different time points (5 and 40 days after infection) with either MA or MF. The efficacy of MF was better than that of MA for inhibiting lesions and for reducing tissue damage and presence/load of amastigotes in spleen and liver. Moreover, early administration of MF produced a clear reduction in splenomegaly and was equal in reducing antibody titles in comparison with MA. Our results demonstrated that MF is an effective and safe therapeutic alternative for leishmaniasis by L. (L.) amazonensis and is more efficacious than MA. PMID:25014108

  9. Morphologic aspects of the Leishmania amazonensis submitted to ionizing radiation

    International Nuclear Information System (INIS)

    Leishmania amazonensis is a protozoan transmitted by a bite of a sandfly responsible for skin lesions in human and other mammalian hosts, being considered one of the most important endemic Public Health disease. Ionizing radiation shown to be an excellent method to kill these parasites, blocking their growth by nucleic acid (DNA) break, and stopping the respiratory metabolism. In this study, we analyze the effects of ionizing radiation on the morphology of the Leishmania amazonensis and the capacity of infection in experimental model. The radio sterilized parasites maintained their membrane surface preserved while destroyed the other proteins needed to their life, promoting the possible of a new antigenic model. (author)

  10. O uso da associação azitromicina e N-metil glucamina no tratamento da leishmaniose cutânea causada por Leishmania (Leishmania) amazonensis em camundongos C57BL6 The use of azythromycin and N-methyl glucamine for the treatment of cutaneous Leishmaniasis caused by Leishmania (Leishmania) amazonensis in C57BL6 mice

    OpenAIRE

    Raimunda Nonata Ribeiro Sampaio; Íris Campos Lucas; Arnoldo Velloso da Costa Filho

    2009-01-01

    FUNDAMENTOS: O tratamento de primeira escolha da leishmaniose tegumentar americana é a N-metil-glucamina que tem alta toxicidade, exige administração parenteral e nem sempre cura. A azitromicina mostrou ação in vitro e resultado contraditório na doença humana. OBJETIVO: Verificar se a associação N-metil-glucamina+azitromicina é mais eficaz do que N-metil-glucamina no tratamento da leishmaniose experimental. MÉTODOS: 25 camundongos inoculados com a cepa C57BL/6 de L. (L.) amazonensis foram div...

  11. Serological reactivity of different antigenic preparations of Leishmania (Leishmania) amazonensis and the Leishmania braziliensis complex / Reatividade sorológica frente a diferentes preparações antigênicas de Leishmania (Leishmania) amazonensis e do complexo Leishmania braziliensis

    Scientific Electronic Library Online (English)

    Adriano, Gomes-Silva; Maria Aparecida, Souza; Sandra Regina, Afonso-Cardoso; Lívia Resende, Andrade; Reynaldo, Dietze; Elenice, Lemos; Alejandro, Belli; Silvio, Favoreto Júnior; Marcelo Simão, Ferreira.

    2008-04-01

    Full Text Available Antígeno total de Leishmania (Leishmania) amazonensis e isolado do complexo Leishmania brazilienis, assim como suas respectivas frações antigênicas obtidas por cromatografia de afinidade em coluna de concanavalina-A ligada a sepharose e Jacalina ligada a agarose foram avaliadas por ensaio imunoenzim [...] ático ELISA. Para tanto, foram utilizadas amostras de soros de 229 pacientes agrupadas em leishmaniose tegumentar americana (nº=58), leishmaniose visceral (nº=28), doença de Chagas (nº=49), malaria (nº=32), tuberculose (nº=13) e voluntários saudáveis (nº=49). Houve maior reatividade das amostras de leishmaniose tegumentar americana com a utilização dos antígenos obtidos do isolado do complexo Leishmania braziliensis quando comparado com antígenos de Leishmania amazonensis (p Abstract in english Total antigen from Leishmania (Leishmania) amazonensis and isolates from the Leishmania braziliensis complex, along with their respective antigenic fractions obtained by affinity chromatography on concanavalin-A-Sepharose and jacalin-agarose columns evaluated using immunoenzymatic ELISA assay. For t [...] his, serum samples from 229 patients were used, grouped as American tegmental leishmaniasis (nº=58), visceral leishmaniasis (nº=28), Chagas disease (nº=49), malaria (nº=32), tuberculosis (nº=13) and healthy volunteers (nº=49). Samples from American tegmentary leishmaniasis showed higher reactivity with antigens isolated from the Leishmania braziliensis complex than with antigens from Leishmania amazonensis (p

  12. Ocorrência de leishmaniose tegumentar americana no Estado do Mato Grosso do Sul associada à infecção por Leishmania (Leishmania) amazonensis / Occurrence of American tegumentary leishmaniasis in the Mato Grosso do Sul State associated to the infection for Leishmania (Leishmania) amazonensis

    Scientific Electronic Library Online (English)

    Maria Elizabeth Moraes Cavalheiros, Dorval; Elisa Teruya, Oshiro; Elisa, Cupollilo; Ana Cristina Camargo de, Castro; Tulia Peixoto, Alves.

    2006-02-01

    Full Text Available São relatados nove casos de leishmaniose tegumentar americana ocorridos no ano de 2001 em uma unidade de treinamento militar localizada no município de Bela Vista, Estado de Mato Grosso do Sul. Parasitas obtidos de lesões de seis pacientes foram isolados em cultura e posteriormente identificados atr [...] avés da análise de isoenzimas como sendo Leishmania (Leishmania) amazonensis. Esta é a primeira evidência da presença desta espécie de parasita em Mato Grosso do Sul. Abstract in english Nine cases of American tegumentary leishmaniasis were reported at a Training Military Unit located in Bela Vista City, State of Mato Grosso do Sul. Parasites obtained from lesions of six patients were isolated in culture media followed by identification, through isoenzymes analysis, as being Leishma [...] nia amazonensis. This is the first evidence of the presence of the parasite in Mato Grosso do Sul.

  13. Leishmaniose cutânea experimental: II - aspectos evolutivos da infecção no primata Cebus apella (Cebidae) pela Leishmania (V.) Braziliensis e L. (L.) Amazonensis

    Scientific Electronic Library Online (English)

    Fernando T., Silveira; Ralph, Lainson; Jeffrey J., Shaw; Lourdes M., Garcez; Adelson A., Souza; Roseli R., Braga; Edna A., Ishikawa.

    1990-03-01

    Full Text Available Objetivando avaliar o potencial do primata C. apella como modelo experimental da leishmaniose cutânea, produzida pela L. (V.) braziliensis e L. (L.) Amazonensis , inocularam-se, via intradérmica, 3 X 10(6) de promastigotas dessas leishmanias, em 8 sítios da cauda de 10 espécimens desse primata, 5 de [...] les com a L. (V.) braziliensis e outros 5 com a L. (L.) Amazonensis . Posteriormente, às inoculações, o exame semanal dos animais e biópsias mensais, revelaram os seguintes resultados relativos a cada parasita: a) L. (V.) braziliensis : o período de incubação foi de 15-20 dias; aos 30 dias evidenciaram-se lesões pápulo-eritematosas, que evoluíram para nódulos ao fim de 60 dias; no 3.° mês, notou-se ulceração espontânea destas lesões e, no 4° mês, deu-se o início da reparação das lesões ulceradas, culminando com a cura em um dos animais após 5 meses, em dois após 6 meses, noutro após 7 meses e, no último, após 10 meses. Quanto ao parasitismo nas lesões, foi demonstrado nos 5 animais, até 90 dias; depois disto, somente em 2 até 120 dias e, por fim, até 180 dias apenas naquele que curou depois de 10 meses, b) L. (L.) Amazonensis : o período de incubação foi de 20 dias; aos 30 dias notou- se lesões pápulo-eritematosas, que também evoluíram para nódulos ao fim de 60 dias, porém, a partir do 3.° mês, estas lesões regrediram rapidamente ao fim de 90 dias, quando não mais detectou-se o parasita na pele dos animais. Em relação aos testes de Montenegro, somente 2 dos 5 animais infectados com a L. (V.) braziliensis reagiram ao teste, 60 e 90 dias após as inoculações. Os resultados observados permitiram confirmar a infectividade do C. apella a estas leishmanias e, também, reforçar a indicação desse primata como modelo experimental da leishmaniose cutânea causada por estes parasitas. Abstract in english As a means of assessing the usufulness of the monkey Cebus apella as an experimental model for the study of cutaneous leishmaniasis, 5 of these animals were inoculated intradermally at 8 sites along the tail with 3 X 106 promastigotes of L. (V.) braziliensis , while a further 5 monkeys received simi [...] lar inoculations with 3 X 10(6) promastigotes of L. (L.) Amazonensis . Following the inoculations, weekly examinations and monthly biopsies showed evolution of resulting skin lesions to be as follows: a) L. (V.) braziliensis : lesions were first visible 15-20 days postinoculation (p.i), and at 30 days they were clearly of an etythematous-papular nature, which assumed a nodular form at 60 days; after 3 months a spontaneous ulceration of these lesions was noted and, at 4 months, the initiation of healing. In one animal total healing was apparent 5 months p.i; in two others at 6 months, in another monkey after 7 months, and in the last animal at 10 months p.i. Amastigotes were demonstrated in smears from the lesions of all monkeys up to 90 days p.i; up to 120 days in two animals, and at 180 days p.i. in the monkey which showed resolution of the lesions after 10 months, b) L. (L.) Amazonensis lesions were first apparent after 20 days p. i; at 30 days they were of an en'thematous-papular nature, developing into nodules at 60 days. From the third month of infection onwards, however, the lesions diminished rapidly and, at 90 days p.i. amastigotes were no longer detectable in the skin. With regards to the Montenegro (leishmanin) skin tests, only two of the monkeys (infected with L. (V.) braziliensis ) gave positive reactions, at 60 and 9 ) days p. i. These results confirm the susceptibility of C. apella to infections with both L. (V.) braziliensis and L. (L.) Amazonensis , and support previous indications that this monkey may serve as an useful experimental model for the study of cutaneous leishmaniasis caused by these parasites.

  14. Studies on the effectiveness of diarylheptanoids derivatives against Leishmania amazonensis

    Scientific Electronic Library Online (English)

    Catarina AC, Araujo; Leila V, Alegrio; Denise CF, Gomes; Marco Edilson F, Lima; Leonardo, Gomes-Cardoso; Leonor L, Leon.

    1999-11-01

    Full Text Available In a previous work we demonstrated that diarylheptanoids extracted from Centrolobium sclerophyllum are very active against Leishmania amazonensis promastigotes. In order to continue our studies with these class of compounds, we decided to evaluate the activity of several diarylheptanoids derived fro [...] m curcumin (diferuloyl methane) against the extracellular form (promastigotes) of L. amazonensis. Furthermore, an experiment against the intracellular form of the parasite (amastigotes) was carried out, comparing the most active compound among the curcumin derivatives (the methylcurcumin) with des-O-methylcentrolobine, the most active diarylheptanoid derived from C. sclerophyllum.

  15. Fusion between Leishmania amazonensis and Leishmania major Parasitophorous Vacuoles: Live Imaging of Coinfected Macrophages

    OpenAIRE

    Real, Fernando; Mortara, Renato A.; Rabinovitch, Michel

    2010-01-01

    Protozoan parasites of the genus Leishmania alternate between flagellated, elongated extracellular promastigotes found in insect vectors, and round-shaped amastigotes enclosed in phagolysosome-like Parasitophorous Vacuoles (PVs) of infected mammalian host cells. Leishmania amazonensis amastigotes occupy large PVs which may contain many parasites; in contrast, single amastigotes of Leishmania major lodge in small, tight PVs, which undergo fission as parasites divide. To determine if PVs of the...

  16. Essential Role of Platelet-Activating Factor in Control of Leishmania (Leishmania) amazonensis Infection

    OpenAIRE

    Lonardoni, Maria Valdrinez Campana; Russo, Momtchillo; Jancar, Sonia

    2000-01-01

    In the present study we investigated the role of platelet-activating factor (PAF) and prostaglandins in experimental Leishmania (Leishmania) amazonensis infection and the relationship between these mediators and nitric oxide (NO) production. Mouse peritoneal macrophages elicited with thioglicolate were infected with leishmania amastigotes, and the infection index determined 48 h later. The course of infection was monitored for 5 weeks in mice infected in the footpad with promastigotes by meas...

  17. Interleukin- 2 production during murine infection by Leishmania mexicana amazonensis

    Scientific Electronic Library Online (English)

    Manoel, Barral-Netto; Silene B., Roters; Aldina, Barral.

    1986-03-01

    Full Text Available Camundongos BALB/c (susceptíveis), C57B1/6 (resistentes) ou sua geração F1 (BDF) foram infectados subcutaneamente na pata traseira com Leishmania mexicana amazonensis. Avaliamos, em diferentes períodos de infecção, a capacidade de células do baço ou de linfonodo poplíteo, de produzir Interleucina-2 [...] (I1-2) em resposta à estimulação por Conconavalina A (ConA). Nos camundongos BALB/c e C57B1/6 observamos, da 3ª à 10ª semana pós-infecção transitória da capacidade de produzir I1-2. Da 13ª à 16ª semana pós-infecção houve um retorno dos níveis de produção pré-infecção. Camundongos BALB/c produziram títulos mais elevados de I2- que os C57B1/6, mas tais diferenças só foram estatisticamente significantes na 3ª e 10ª semanas pós-infecção. Camundongos BDF1 apresentaram títulos semelhantes aos dos BALB/c. Os níveis de I1-2 (estimulada por ConA) produzidos por células do linfonodo foram mais baixos que os baço, porém com padrão semelhante. Nossos dados mostram que a susceptibilidade à infecção por L. mexicana amazonensis não está associada a um defeito de produção de I1-2, estimulada por ConA. Abstract in english Highly susceptible BALB/c mice, resistant C57B1/6 and their F1 progeny (BDF1) were infected subcutaneously in the foot pad with Leishmania mexicana amazonenesis. At various times after infection, spleen or draining popliteal lymph node cells were assayed for their capacity to generate Interleukin-2 [...] (I1-2) by Concanavalin A (ConA) stimulation. In both BALB/c and C57B1/6 strains there was a transient increase in their capacity to produce I1-2, from the 3rd to the 10th week post-infection. Return to pre-infection levels ocurred between 13th to 16th week post-infection in all three strains. BALB/c mice always produced higher titers of 11-2 than C57B1/6, but such differences were statistically significant only at 3 and 10 weeks post-infection. BDF1 mice had titers similar to those observed in BALB/c mice. I1-2 production by ConA-stimulated lymph node cells was lower as compared to the spleen, but with a similar pattern among the three mice strains. Our data show that susceptibility to infection by l. mexicana amazonenesis is not associated with deficient ConA-stimulated I1-2 production.

  18. Interleukin- 2 production during murine infection by Leishmania mexicana amazonensis

    Directory of Open Access Journals (Sweden)

    Manoel Barral-Netto

    1986-03-01

    Full Text Available Highly susceptible BALB/c mice, resistant C57B1/6 and their F1 progeny (BDF1 were infected subcutaneously in the foot pad with Leishmania mexicana amazonenesis. At various times after infection, spleen or draining popliteal lymph node cells were assayed for their capacity to generate Interleukin-2 (I1-2 by Concanavalin A (ConA stimulation. In both BALB/c and C57B1/6 strains there was a transient increase in their capacity to produce I1-2, from the 3rd to the 10th week post-infection. Return to pre-infection levels ocurred between 13th to 16th week post-infection in all three strains. BALB/c mice always produced higher titers of 11-2 than C57B1/6, but such differences were statistically significant only at 3 and 10 weeks post-infection. BDF1 mice had titers similar to those observed in BALB/c mice. I1-2 production by ConA-stimulated lymph node cells was lower as compared to the spleen, but with a similar pattern among the three mice strains. Our data show that susceptibility to infection by l. mexicana amazonenesis is not associated with deficient ConA-stimulated I1-2 production.Camundongos BALB/c (susceptíveis, C57B1/6 (resistentes ou sua geração F1 (BDF foram infectados subcutaneamente na pata traseira com Leishmania mexicana amazonensis. Avaliamos, em diferentes períodos de infecção, a capacidade de células do baço ou de linfonodo poplíteo, de produzir Interleucina-2 (I1-2 em resposta à estimulação por Conconavalina A (ConA. Nos camundongos BALB/c e C57B1/6 observamos, da 3ª à 10ª semana pós-infecção transitória da capacidade de produzir I1-2. Da 13ª à 16ª semana pós-infecção houve um retorno dos níveis de produção pré-infecção. Camundongos BALB/c produziram títulos mais elevados de I2- que os C57B1/6, mas tais diferenças só foram estatisticamente significantes na 3ª e 10ª semanas pós-infecção. Camundongos BDF1 apresentaram títulos semelhantes aos dos BALB/c. Os níveis de I1-2 (estimulada por ConA produzidos por células do linfonodo foram mais baixos que os baço, porém com padrão semelhante. Nossos dados mostram que a susceptibilidade à infecção por L. mexicana amazonensis não está associada a um defeito de produção de I1-2, estimulada por ConA.

  19. Serological reactivity of different antigenic preparations of Leishmania (Leishmania amazonensis and the Leishmania braziliensis complex Reatividade sorológica frente a diferentes preparações antigênicas de Leishmania (Leishmania amazonensis e do complexo Leishmania braziliensis

    Directory of Open Access Journals (Sweden)

    Adriano Gomes-Silva

    2008-04-01

    Full Text Available Total antigen from Leishmania (Leishmania amazonensis and isolates from the Leishmania braziliensis complex, along with their respective antigenic fractions obtained by affinity chromatography on concanavalin-A-Sepharose and jacalin-agarose columns evaluated using immunoenzymatic ELISA assay. For this, serum samples from 229 patients were used, grouped as American tegmental leishmaniasis (nº=58, visceral leishmaniasis (nº=28, Chagas disease (nº=49, malaria (nº=32, tuberculosis (nº=13 and healthy volunteers (nº=49. Samples from American tegmentary leishmaniasis showed higher reactivity with antigens isolated from the Leishmania braziliensis complex than with antigens from Leishmania amazonensis (pAntígeno total de Leishmania (Leishmania amazonensis e isolado do complexo Leishmania brazilienis, assim como suas respectivas frações antigênicas obtidas por cromatografia de afinidade em coluna de concanavalina-A ligada a sepharose e Jacalina ligada a agarose foram avaliadas por ensaio imunoenzimático ELISA. Para tanto, foram utilizadas amostras de soros de 229 pacientes agrupadas em leishmaniose tegumentar americana (nº=58, leishmaniose visceral (nº=28, doença de Chagas (nº=49, malaria (nº=32, tuberculose (nº=13 e voluntários saudáveis (nº=49. Houve maior reatividade das amostras de leishmaniose tegumentar americana com a utilização dos antígenos obtidos do isolado do complexo Leishmania braziliensis quando comparado com antígenos de Leishmania amazonensis (p<0,001. Observou-se ainda que a sensibilidade do teste ELISA variou de 60 a 95% entre os antígenos obtidos do isolado do complexo Leishmania braziliensis. Houve acentuada reatividade inespecífica das amostras de soros com a utilização das frações antigênicas ligantes de Concanavalina-A e Jacalina de ambos os complexos Leishmania em comparação aos demais antígenos (p<0,001. Os resultados apresentados no presente trabalho sugerem que a utilização de antígenos homólogos aumentam a eficiência de detecção de imunoglobulina anti-Leishmania o que pode ser de grande valia para o propósito de diagnóstico.

  20. Leishmania amazonensis exhibits phosphatidylserine-dependent procoagulant activity, a process that is counteracted by sandfly saliva

    OpenAIRE

    Rochael, Natalia Cadaxo; Lima, Luize Gonçalves; de Oliveira, Sandra Maria Pereira; Barcinski, Marcello André; Saraiva, Elvira Maria; Monteiro, Robson Queiroz; Pinto-da-Silva, Lucia Helena

    2013-01-01

    Leishmania parasites expose phosphatidylserine (PS) on their surface, a process that has been associated with regulation of host's immune responses. In this study we demonstrate that PS exposure by metacyclic promastigotes of Leishmania amazonensis favours blood coagulation. L. amazonensis accelerates in vitro coagulation of human plasma. In addition, L. amazonensis supports the assembly of the prothrombinase complex, thus promoting thrombin formation. This process was re...

  1. Metaciclogénesis y desarrollo de Leishmania (Leishmania) amazonensis (Kinetoplastida: Trypanosomatidae) en Lutzomyia ovallesi (Diptera: Psychodidae) / Metacyclogenesis and development of Leishmania (Leishmania) amazonensis (Kinetoplastida: Trypanosomatidae) in Lutzomyia ovallesi (Diptera: Psychodidae)

    Scientific Electronic Library Online (English)

    Elsa, Nieves; Maritza, Rondón.

    2010-12-01

    Full Text Available La interacción Leishmania-vector es un proceso complejo y multifactorial. En los últimos años se han logrado avances importantes en la relación Leishmania-vector, pero aún se desconocen algunos aspectos. Este trabajo estudia la interacción de Leishmania (Leishmania) amazonensis (Kinetoplastida: Tryp [...] anosomadidae) en Lutzomyia ovallesi (Diptera: Psychodidae). Hembras de L. ovallesi fueron infectadas artificialmente y se determinó el patrón de desarrollo, densidad parasitaria, secuencia de morfotipos de promastigotes en las regiones del intestino, efecto de la realimentación, y el patrón de carbohidratos de la superficie de las leptomonas usando lectinas fluorescentes. Los resultados mostraron desarrollo suprapilórico de L. (L.) amazonensis. La densidad parasitaria mostró dos ciclos de división separados en tiempo y espacio, se observaron morfotipos caracterizados como paramastigotes en división. La realimentación no alteró la migración de los morfotipos y la mayor proporción de leptomonas en el intestino medio torácico sugiere migración natural que pudiera ser modulada por el gradiente de carbohidratos en el intestino del flebótomo y por la exposición de saliva. Las leptomonas exhibieron diferentes patrones de unión de glicoconjugados, que sugieren presencia de distintos residuos de carbohidratos en la superficie celular del parásito y/o flagelo, que pueden tener funciones importantes en la interacción y estabilidad de los parásitos en el lumen del intestino y su migración a las diferentes regiones del mismo. Se aportan diferentes aspectos del desarrollo de L. (L.) amazonensis en L. ovallesi importantes para entender su potencial vectorial Abstract in english Leishmania-vector interaction is a complex and multifactorial process. During the last few years important advances in the Leishmania-vector interaction have been reached but there still some unknown aspects. This work studies the Leishmania (Leishmania) amazonensis (Kinetoplastide: Trypanosomatidae [...] ) interaction in Lutzomia ovallesi (Diptera: Psychodidae). L. ovallesi females were artificially infected and the development pattern, parasite density, and promastigote morphotype sequence in the intestinal regions were determined, as well as the effect of re-feeding, and the carbohydrate pattern of the leptomonad surface using fluorescent lectins. The results showed suprapiloric development of L. (L.)amazonensis. Parasite density showed two division cycles separated in time and space, morphotypes characterized as dividing paramastigotes were observed. Re-feeding did not alter the migration of morphotypes and the greater proportion of leptomonads in the middle intestine suggests a natural migration which could be modulated by the carbohydrate gradient in the phlebotom intestine and by exposure to saliva. Leptomonads exhibited different glyconjugate union patterns which suggest the presence of various carbohydrate residues in the cell surface of the parasite and/or flagellum, which can have important functions in the interaction and stability of the parasites in the intestinal lumen and their migration to the different intestinal regions. Several aspects of L. (L.)amazonensis development in L. ovallesi important for understanding its vectorial potency are discussed

  2. Comparative two-dimensional gel electrophoresis maps for promastigotes of Leishmania amazonensis and Leishmania major

    Scientific Electronic Library Online (English)

    Reynolds K. B., Brobey; Fang C., Mei; Xiaodong, Cheng; Lynn, Soong.

    2006-02-01

    Full Text Available The outcome of Leishmania infections is determined by both the parasite species and the host genetic makeup. While much has been learned regarding immune responses to this parasite, our knowledge on parasite-derived factors is limited. The recent completion of the L. major and L. infantum genome seq [...] uence projects and concurrent advancement in proteomics technology would greatly accelerate the search for novel Leishmania proteins. Using a proteomics-based approach to study species-specific Leishmania proteins, we developed high-resolution, broad pH (3-10) two-dimensional gel electrophoresis (2-DE) separations to determine protein-expression profiles between highly infectious forms of the parasitic species L. amazonensis (New World) and L. major (Old World). Approximately 1,650 and 1,530 distinct protein spots were detected in the L. amazonensis and L. major gels, respectively. While a vast majority of the spots had similar distribution and intensity, a few were computationally defined as preferentially expressed in L. amazonensis in comparison to L. major, or vice versa. These data attest to the feasibility of establishing a 2-DE-based protein array for inter-species profiling of Leishmania proteins and provide the framework for future design of proteome studies of Leishmania.

  3. Comparative two-dimensional gel electrophoresis maps for promastigotes of Leishmania amazonensis and Leishmania major

    Directory of Open Access Journals (Sweden)

    Reynolds K. B. Brobey

    2006-02-01

    Full Text Available The outcome of Leishmania infections is determined by both the parasite species and the host genetic makeup. While much has been learned regarding immune responses to this parasite, our knowledge on parasite-derived factors is limited. The recent completion of the L. major and L. infantum genome sequence projects and concurrent advancement in proteomics technology would greatly accelerate the search for novel Leishmania proteins. Using a proteomics-based approach to study species-specific Leishmania proteins, we developed high-resolution, broad pH (3-10 two-dimensional gel electrophoresis (2-DE separations to determine protein-expression profiles between highly infectious forms of the parasitic species L. amazonensis (New World and L. major (Old World. Approximately 1,650 and 1,530 distinct protein spots were detected in the L. amazonensis and L. major gels, respectively. While a vast majority of the spots had similar distribution and intensity, a few were computationally defined as preferentially expressed in L. amazonensis in comparison to L. major, or vice versa. These data attest to the feasibility of establishing a 2-DE-based protein array for inter-species profiling of Leishmania proteins and provide the framework for future design of proteome studies of Leishmania.

  4. Leishmania amazonensis: acidic organelles in amastigotes.

    Science.gov (United States)

    Antoine, J C; Jouanne, C; Ryter, A; Benichou, J C

    1988-12-01

    Leishmania amastigotes are intracellular protozoan parasites which exclusively invade cells of the macrophage series and multiply within phagolysosomes. Recent studies showed that intracellular and isolated amastigotes of L. amazonesis are killed by amino acid esters which appear to be trapped within as yet unidentified, possibly acidified, "lysosome-like" parasite compartments and cleaved by hydrolytic enzyme(s) (M. Rabinovitch, V. Zilberfarb, and C. Ramazeilles, 1986, Journal of Experimental Medicine 163, 520-535). In the present study, we have localized acidic compartments of Leishmania amastigotes using as a probe the weak base 3-(2,4 dinitroanilino)-3'-amino-N-methyldipropylamine (DAMP). This indicator, which can be detected within cells by light and electron microscopy using immunocytochemical immunocytochemical methods, mainly accumulates within megasomes and in dense inclusion vacuoles. With the help of quantitative assays to titrate cell-associated DAMP, it was found that (a) its uptake is temperature dependent and thus probably requires an energy supply, (b) the proton ionophore monensin partially inhibits the trapping of DAMP, and (c) monensin greatly increases its efflux from cells. These results, as well as those obtained by quantitative ultrastructural immunocytochemistry of cells incubated with DAMP in the absence or presence of monensin, show that megasomes and inclusion vacuoles have a low pH probably maintained by an active process. Furthermore, confirming the report of H. F. Hassan and G. H. Coombs (1987, Molecular and Biochemical Parasitology 23, 285-296) megasomes were found to display acid phosphatase activity at both light and electron microscope levels. This, together with the demonstration that megasomes are acidified, suggests that these organelles may be targets for amino acid derivatives. PMID:3056736

  5. O uso da associação azitromicina e N-metil glucamina no tratamento da leishmaniose cutânea causada por Leishmania (Leishmania amazonensis em camundongos C57BL6 The use of azythromycin and N-methyl glucamine for the treatment of cutaneous Leishmaniasis caused by Leishmania (Leishmania amazonensis in C57BL6 mice

    Directory of Open Access Journals (Sweden)

    Raimunda Nonata Ribeiro Sampaio

    2009-04-01

    Full Text Available FUNDAMENTOS: O tratamento de primeira escolha da leishmaniose tegumentar americana é a N-metil-glucamina que tem alta toxicidade, exige administração parenteral e nem sempre cura. A azitromicina mostrou ação in vitro e resultado contraditório na doença humana. OBJETIVO: Verificar se a associação N-metil-glucamina+azitromicina é mais eficaz do que N-metil-glucamina no tratamento da leishmaniose experimental. MÉTODOS: 25 camundongos inoculados com a cepa C57BL/6 de L. (L. amazonensis foram divididos em dois grupos. Um foi tratado com 400mgSbV/kg/dia de N-metil-glucamina associado a 200mg/kg/dia de azitromicina durante 20 dias, e o outro com N-metil-glucamina, na mesma dose, durante o mesmo tempo. Foi feita avaliação clínica e parasitológica com análise estatística. RESULTADO: Na avaliação clínica, pesquisa de amastigotas e das culturas, não houve diferença estatística. Verificou-se, entretanto, diferença significante no resultado das culturas realizadas através de diluição limitante, que desfavoreceu a associação NMG+ azitromicina. CONCLUSÃO: A associação N-metil-glucamina e azitromicina não demonstrou mais eficácia do que o N-metil-glucamina em uso isolado.BACKGROUND: The first choice treatment for cutaneous Leishmaniasis is N-methyl glucamine: it has high toxicity, requires parenteral administration and cure is not always reached. Azythromycin showed in vitro action and controversial results in humans with the disease. OBJECTIVE: To verify if the association of N-methyl-glucamine - azythromycin is more effective than N-methyl-glucamine alone for the treatment of experimental Leishmaniasis. METHODS: Twenty-five C57BL/6 mice were inoculated with L. (L. amazonensis strain and divided into two groups. One group was treated with 400mgSbV/kg/day of N-methyl glucamine and 200mg/kg/day of azythromycin for 20 days and the other group received the same dose of N-methyl glucamine alone during the same period of time. Clinical and parasitological evaluations were submitted to statistical analyses. RESULTS: There was no statistical difference in clinical analysis, in amastigotes investigation and in cultures. There were significant differences in cultures using limiting dilution, which showed lower efficacy of the association N-methyl glucamine -azythromycin. CONCLUSION: N-methyl glucamine-azythromycin association was not more effective than N-methyl glucamine alone.

  6. O uso da associação azitromicina e N-metil glucamina no tratamento da leishmaniose cutânea causada por Leishmania (Leishmania) amazonensis em camundongos C57BL6 / The use of azythromycin and N-methyl glucamine for the treatment of cutaneous Leishmaniasis caused by Leishmania (Leishmania) amazonensis in C57BL6 mice

    Scientific Electronic Library Online (English)

    Raimunda Nonata Ribeiro, Sampaio; Íris Campos, Lucas; Arnoldo Velloso da, Costa Filho.

    2009-04-01

    Full Text Available FUNDAMENTOS: O tratamento de primeira escolha da leishmaniose tegumentar americana é a N-metil-glucamina que tem alta toxicidade, exige administração parenteral e nem sempre cura. A azitromicina mostrou ação in vitro e resultado contraditório na doença humana. OBJETIVO: Verificar se a associação N-m [...] etil-glucamina+azitromicina é mais eficaz do que N-metil-glucamina no tratamento da leishmaniose experimental. MÉTODOS: 25 camundongos inoculados com a cepa C57BL/6 de L. (L.) amazonensis foram divididos em dois grupos. Um foi tratado com 400mgSbV/kg/dia de N-metil-glucamina associado a 200mg/kg/dia de azitromicina durante 20 dias, e o outro com N-metil-glucamina, na mesma dose, durante o mesmo tempo. Foi feita avaliação clínica e parasitológica com análise estatística. RESULTADO: Na avaliação clínica, pesquisa de amastigotas e das culturas, não houve diferença estatística. Verificou-se, entretanto, diferença significante no resultado das culturas realizadas através de diluição limitante, que desfavoreceu a associação NMG+ azitromicina. CONCLUSÃO: A associação N-metil-glucamina e azitromicina não demonstrou mais eficácia do que o N-metil-glucamina em uso isolado. Abstract in english BACKGROUND: The first choice treatment for cutaneous Leishmaniasis is N-methyl glucamine: it has high toxicity, requires parenteral administration and cure is not always reached. Azythromycin showed in vitro action and controversial results in humans with the disease. OBJECTIVE: To verify if the ass [...] ociation of N-methyl-glucamine - azythromycin is more effective than N-methyl-glucamine alone for the treatment of experimental Leishmaniasis. METHODS: Twenty-five C57BL/6 mice were inoculated with L. (L.) amazonensis strain and divided into two groups. One group was treated with 400mgSbV/kg/day of N-methyl glucamine and 200mg/kg/day of azythromycin for 20 days and the other group received the same dose of N-methyl glucamine alone during the same period of time. Clinical and parasitological evaluations were submitted to statistical analyses. RESULTS: There was no statistical difference in clinical analysis, in amastigotes investigation and in cultures. There were significant differences in cultures using limiting dilution, which showed lower efficacy of the association N-methyl glucamine -azythromycin. CONCLUSION: N-methyl glucamine-azythromycin association was not more effective than N-methyl glucamine alone.

  7. Cell migration induced by Leishmania (Leishmania) amazonensis, Leishmania (Leishmania) major and Leishmania (Viannia) braziliensis into the peritoneal cavity of BALB/c mice

    Scientific Electronic Library Online (English)

    DT, Wakimoto; KV, Gaspareto; TGV, Silveira; MVC, Lonardoni; SMA, Aristides.

    Full Text Available In American cutaneous leishmaniasis, the initial infection phase is characterized by recruitment of neutrophils and monocytes. The migration of these cells in response to the presence of Leishmania in the peritoneum of affected animals remains unclear. The objective of this study was to investigate [...] cell migration to the peritoneum of BALB/c mice after infection with Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis and Leishmania (Leishmania) major. Initially, Leishmania spp. was intraperitoneally inoculated in five groups of six animals each and the cell migration was analyzed 0, 3, 6, 12, 24 and 48 hours after infection. Different cell counts were performed with a staining kit and showed a higher percentage of polymorphonuclear than mononuclear cells in all three species studied. The total cell count revealed peak migration in L. (L.) amazonensis and L. (L.) major at six hours, and in L. (V.) braziliensis at 12 hours. These results suggest that factors released from different cell types probably act by attracting polymorphonuclear cells, with the peak migration most likely depending on the species of Leishmania inoculated into the host.

  8. Desarrollo de Leishmania mexicana y Leishmania amazonensis en Lutzomyia evansi (Díptera: Psychodidae, Phlebotomine Development of Leishmania mexicana and Leishmania amazonensis in Lutzomyia evansi (Díptera: Psychodidae, Phlebotomine

    Directory of Open Access Journals (Sweden)

    MARÍA ALEJANDRA VIVENES

    2005-06-01

    Full Text Available El objetivo de este trabajo consistió en estudiar los cambios morfológicos que ocurren durante el desarrollo de Leishmania mexicana (MHOM/VE/72/AZV y Le. amazonensis (IFLA/BR/67/PI18 en Lutzomyia euansi. Hembras de Lu. evansi se alimentaron a partir de una lesión tarsal de hámster y se examinaron en busca de infección cada 24 h hasta las 168 h posalimentación. El patrón de desarrollo de Le. mexicana y Le. amazonensis en Lu. euansi fue de tipo suprapilórico, de acuerdo con lo descrito para las especies del complejo Le. mexicana. La transformación de formas amastigotas a procíclicos ocurrió para ambas especies entre las 24 - 48 h postinfección. Los parásitos mostraron su adaptación al microambiente del tracto digestivo de Lu. euansi y desarrollo hacia formas maduras: nectomonas, haptomonas y paramastigotas. La forma paramastigota se observó, en bajo porcentaje, a las 120 h postingesta infectiva en ambas especies. La disminución temprana de nutrientes en Lu. euansi, debido al rápido proceso de digestión de sangre (3 a 4 días, pudiera explicar el bajo porcentaje de desarrollo alcanzado hacia las formas paramastigotas y la ausencia de formas metacíclicas en este modelo.The aim of this paper was to study the morphological changes in the development of Leishmania mexicana (MMOM/VE/72/AZV and L. amazonensis (IFLA/BR/67/PI18 in Lutzomyia euansi. Pernales of Lu. euansi fed on a hámster tarsal lesión and were examined for infection at 24 h intervals from 24 h to 168 h post- feeding. The pattern of development of Le. mexicana and Le. amazonensis in Lu. euansi was suprapylarian consistentwith what has been described forspecies of the Le. mexicana complex. Transformaron from amastigote to procyclical forms occurred in both species at 24 - 48 h post-infection. The parasites showed their adaptaüon lo the gut environment of Lu. euansi and development to mature forms: nectomonads, haptomonads and pararnastigotes. The paramastigote form was observed in low percentage at 120 h post-infected ingestión in both species. The early depletion of nutrients in Lu. euansi, due to a faster rate of digestión (3 to 4 days, could explain the low percentage of development reaching the paramastigote forms and the absence of the metacyclical forms in this model.

  9. Desarrollo de Leishmania mexicana y Leishmania amazonensis en Lutzomyia evansi (Díptera: Psychodidae, Phlebotomine) / Development of Leishmania mexicana and Leishmania amazonensis in Lutzomyia evansi (Díptera: Psychodidae, Phlebotomine)

    Scientific Electronic Library Online (English)

    MARÍA ALEJANDRA, VIVENES; MILAGROS, OVIEDO; JULIO CÉSAR, MÁRQUEZ.

    2005-06-01

    Full Text Available El objetivo de este trabajo consistió en estudiar los cambios morfológicos que ocurren durante el desarrollo de Leishmania mexicana (MHOM/VE/72/AZV) y Le. amazonensis (IFLA/BR/67/PI18) en Lutzomyia euansi. Hembras de Lu. evansi se alimentaron a partir de una lesión tarsal de hámster y se examinaron [...] en busca de infección cada 24 h hasta las 168 h posalimentación. El patrón de desarrollo de Le. mexicana y Le. amazonensis en Lu. euansi fue de tipo suprapilórico, de acuerdo con lo descrito para las especies del complejo Le. mexicana. La transformación de formas amastigotas a procíclicos ocurrió para ambas especies entre las 24 - 48 h postinfección. Los parásitos mostraron su adaptación al microambiente del tracto digestivo de Lu. euansi y desarrollo hacia formas maduras: nectomonas, haptomonas y paramastigotas. La forma paramastigota se observó, en bajo porcentaje, a las 120 h postingesta infectiva en ambas especies. La disminución temprana de nutrientes en Lu. euansi, debido al rápido proceso de digestión de sangre (3 a 4 días), pudiera explicar el bajo porcentaje de desarrollo alcanzado hacia las formas paramastigotas y la ausencia de formas metacíclicas en este modelo. Abstract in english The aim of this paper was to study the morphological changes in the development of Leishmania mexicana (MMOM/VE/72/AZV) and L. amazonensis (IFLA/BR/67/PI18) in Lutzomyia euansi. Pernales of Lu. euansi fed on a hámster tarsal lesión and were examined for infection at 24 h intervals from 24 h to 168 h [...] post- feeding. The pattern of development of Le. mexicana and Le. amazonensis in Lu. euansi was suprapylarian consistentwith what has been described forspecies of the Le. mexicana complex. Transformaron from amastigote to procyclical forms occurred in both species at 24 - 48 h post-infection. The parasites showed their adaptaüon lo the gut environment of Lu. euansi and development to mature forms: nectomonads, haptomonads and pararnastigotes. The paramastigote form was observed in low percentage at 120 h post-infected ingestión in both species. The early depletion of nutrients in Lu. euansi, due to a faster rate of digestión (3 to 4 days), could explain the low percentage of development reaching the paramastigote forms and the absence of the metacyclical forms in this model.

  10. A dhfr-ts- Leishmania major Knockout Mutant Cross-protects against Leishmania amazonensis

    Directory of Open Access Journals (Sweden)

    PST Veras

    1999-07-01

    Full Text Available E10-5A3 is a dhfr-ts- Leishmania major double knockout auxotrophic shown previously to induce substantial protection against virulent L. major infection in both genetically susceptible and resistant mice. We investigated the capacity of dhfr-ts- to protect against heterologous infection by L. amazonensis. The degree of protection was evaluated by immunization of BALB/c or C57BL/6 mice with E10-5A3, followed by L. amazonensis challenge. Whether immunized by subcutaneous (SC or intravenous (IV inoculation, susceptible and resistant mice displayed a partial degree of protection against challenge with virulent L. amazonensis. SC-immunized BALB/c mice developed lesions 40 to 65% smaller than non immunized mice, while IV immunization led to protection ranging from 40 to 75% in four out of six experiments compared to non immunized animals. The resistant C57BL/6 mice displayed comparable degrees of protection, 57% by SC and 49% by IV immunization. Results are encouraging as it has been previously difficult to obtain protection by SC vaccination against Leishmania, the preferred route for human immunization.

  11. LaRbp38: A Leishmania amazonensis protein that binds nuclear and kinetoplast DNAs

    International Nuclear Information System (INIS)

    Leishmania amazonensis causes a wide spectrum of leishmaniasis. There are no vaccines or adequate treatment for leishmaniasis, therefore there is considerable interest in the identification of new targets for anti-leishmania drugs. The central role of telomere-binding proteins in cell maintenance makes these proteins potential targets for new drugs. In this work, we used a combination of purification chromatographies to screen L. amazonensis proteins for molecules capable of binding double-stranded telomeric DNA. This approach resulted in the purification of a 38 kDa polypeptide that was identified by mass spectrometry as Rbp38, a trypanosomatid protein previously shown to stabilize mitochondrial RNA and to associate with nuclear and kinetoplast DNAs. Western blotting and supershift assays confirmed the identity of the protein as LaRbp38. Competition and chromatin immunoprecipitation assays confirmed that LaRbp38 interacted with kinetoplast and nuclear DNAs in vivo and suggested that LaRbp38 may have dual cellular localization and more than one function

  12. Experimental infection of Lutzomyia longipalpis fed on a patient with cutaneous leishmaniasis due to Leishmania mexicana amazonensis

    OpenAIRE

    Deane, Leonidas M.; Elizabeth Ferreira Rangel; Manoel Paes-Oliveira; Gabriel Grimaldi Junior; Hooman Momen; Nataly de Souza; Eduardo D. Wermelinger; André F. Barbosa

    1986-01-01

    The authors were able to infect phlebotomine sandflies on a human case of American Cutaneous Leishmaniasis by feeding females of Lutzomyia longipalpis on a patient with a lesion due to Leishmania mexicana amazonensis.Os autores lograram infectar flebótomos em um caso humano de leishmaniose tegumentar americana fazendo fêmeas de Lutzomyia longipalpis se alimentarem em paciente com lesões devida à Leishmania mexicana amazonensis.

  13. Study of ionizing radiation as a tool for select promastigotes forms of Leishmania Amazonensis, and the megalomaniac response in experimental models; Estudo do uso da radiacao ionizante como ferramenta de selecao de formas promastigotas metaciclicas de Leishmania amazonensis, e a inducao de resposta imunologica em modelos experimentais

    Energy Technology Data Exchange (ETDEWEB)

    Bonetti, Franco Claudio

    2006-07-01

    Actually, millions of people around the globe are under the risk of infection by a protozoan transmitted by a bit of a sand fly. This parasite is a Leishmania spp. This causes a wide spectrum disease, since a cutaneous disease to a visceral one. The cutaneous form is the major clinical manifestation (above 90%). The ionizing radiation, produced in a {sup 60}Co font, had being successes used to promote physical-chemical transformations on different protozoan, including Leishmania spp. In previous work was determined that promastigotes forms of Leishmania amazonensis, irradiated with different doses of radiation, lost their viability maintaining, however, their immunogenicity. In this work, was studied the use of ionizing radiation as a tool for selection of meta cyclic forms of the parasite in axenic culture, for a possible efficient irradiated immuno gene production. Our results shown that cultures irradiated with 400 Gy of gamma irradiation, has 75% of metacyclic form, which are capable to produce, in vitro, an infection that is similar the natural occurrence. These irradiated parasites have their internal cellular structure modified, maintaining their external structure intact. Susceptible strain of mice immunized with leishmania irradiated with different doses had high immunoglobulin production, and maintained this production after the challenge with naive parasites. In other strains this default was similar, however in lower titles. Immunodeficient mice didn't produce immunoglobulin nor on the immunization or on the challenge. (author)

  14. Control of Parasitophorous Vacuole Expansion by LYST/Beige Restricts the Intracellular Growth of Leishmania amazonensis

    OpenAIRE

    Wilson, Jude; Huynh, Chau; Kennedy, Kathleen A.; Ward, Diane M.; Kaplan, Jerry; Aderem, Alan; Norma W. Andrews

    2008-01-01

    The intracellular protozoan Leishmania replicates in parasitophorous vacuoles (PV) that share many features with late endosomes/lysosomes. L. amazonensis PVs expand markedly during infections, but the impact of PV size on parasite intracellular survival is still unknown. Here we show that host cells infected with L. amazonensis upregulate transcription of LYST/Beige, which was previously shown to regulate lysosome size. Mutations in LYST/Beige caused further PV expansion and enhanced L. amazo...

  15. Action of pentoxifylline on experimental cutaneous leishmaniasis due to Leishmania (Leishmania amazonensis

    Directory of Open Access Journals (Sweden)

    Oliveira Thiago de Sá

    2000-01-01

    Full Text Available In the animal model of leishmaniasis caused by Leishmania (Leishmania amazonensis there is a complex mechanism of the host-parasite interaction. The present study was performed to interfere with the inflammatory reaction to the parasites, through immune modulation. Female C5BL/6 isogenic mice were used, some of which were inoculated on the right ear and others on the right footpad with 3.10(6 stationary phase promastigotes of the MHOM/BR/PH8 strain of L. (L. amazonensis, and were allocated in three groups: the first received pentoxifylline 8mg/kg every 12 h, since the first day; the second one received the same dose since the 40th day of infection and a control group that did not receive any treatment. All the ears excised were analyzed to determine the variation in weight between both ears and for histopathological analyses. A quantification of the parasites was done using the limiting dilution assay. A significant reduction of the number of parasites, was observed among the animals treated which had an accordingly significant reduction on the weight of the ears. Pentoxifylline reduced the macrophages propensity to vacuolation and induced a more effective destruction of the parasites by these cells. Moreover, the group that began the treatment later did not show the same effectiveness.

  16. Essential Role of Platelet-Activating Factor in Control of Leishmania (Leishmania) amazonensis Infection

    Science.gov (United States)

    Lonardoni, Maria Valdrinez Campana; Russo, Momtchillo; Jancar, Sonia

    2000-01-01

    In the present study we investigated the role of platelet-activating factor (PAF) and prostaglandins in experimental Leishmania (Leishmania) amazonensis infection and the relationship between these mediators and nitric oxide (NO) production. Mouse peritoneal macrophages elicited with thioglicolate were infected with leishmania amastigotes, and the infection index determined 48 h later. The course of infection was monitored for 5 weeks in mice infected in the footpad with promastigotes by measuring the footpad swelling and parasite load in regional lymph nodes and spleen. The addition of PAF to C57BL/6 mouse macrophages significantly inhibited parasite growth and induced NO production. Treatment of macrophages with a selective PAF antagonist, WEB2086, increased the infection, indicating that endogenously produced PAF regulates macrophage ability to control leishmania infection. This effect of PAF was abolished by addition of the inhibitor of NO synthesis, L-NAME, to the cultures. The addition of prostaglandin E2 significantly increased the infection and NO production. Treatment with cyclo-oxygenase inhibitor, indomethacin, reduced the infection and PAF-induced release of NO. Thus, the increased NO production induced by PAF seems to be mediated by prostaglandins. The more-selective inhibitors of cyclo-oxygenase 2, nimesulide and NS-398, had no significant effect. Thus, antileishmanial activity correlates better with the presence of PAF or absence of prostaglandins than with NO production. In vivo treatment with PAF antagonists significantly increased leishmania lesions, as well as the parasite load, in regional lymph nodes and spleens. These findings indicate that PAF is essential for the control of leishmania infection. PMID:11035745

  17. Correlation of meta 1 expression with culture stage, cell morphology and infectivity in Leishmania (Leishmania) amazonensis promastigotes

    OpenAIRE

    Marcos Gonzaga dos Santos; Maria Fernanda Laranjeira da Silva; Ricardo Andrade Zampieri; Rafaella Marino Lafraia; Lucile Maria Floeter-Winter

    2011-01-01

    The parasitic protozoan Leishmania (Leishmania) amazonensis alternates between mammalian and insect hosts. In the insect host, the parasites proliferate as procyclic promastigotes andthen differentiate into metacyclic infective forms. The meta 1 gene is preferentially expressed during metacyclogenesis. Meta 1 expression profile determination along parasite growth curves revealed that the meta 1 mRNA level peaked at the early stationary phase then decreased to an intermediate level. No correla...

  18. Sand fly captures with Disney traps in area of occurrence of Leishmania (Leishmania amazonensis in the state of Mato Grosso do Sul, mid-western Brazil Capturas de flebotomíneos com armadilhas de Disney em área de ocorrência de Leishmania (Leishmania amazonensis no estado de Mato Grosso do Sul, região Centro-Oeste do Brasil

    Directory of Open Access Journals (Sweden)

    Maria Elizabeth Cavalheiros Dorval

    2010-10-01

    Full Text Available INTRODUCTION: The work was conducted to study phlebotomine fauna (Diptera: Psychodidae and aspects of American cutaneous leishmaniasis transmission in a forested area where Leishmania (Leishmania amazonensis occurs, situated in the municipality of Bela Vista, State of Mato Grosso do Sul, Brazil. METHODS: The captures were conducted with modified Disney traps, using hamster (Mesocricetus auratus as bait, from May 2004 to January 2006. RESULTS: Ten species of phlebotomine sandflies were captured: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni and Sciopemyia sordellii. The two predominant species were Ev bourrouli (57.3% and Bi flaviscutellata (41.4%, present at all sampling sites. Two of the 36 hamsters used as bait presented natural infection with Leishmania. The parasite was identified as Leishmania (Leishmania amazonensis. CONCLUSIONS: Analysis of the results revealed the efficiency of Disney traps for capturing Bichromomyia flaviscutellata and the simultaneous presence of both vector and the Leishmania species transmitted by the same can be considered a predictive factor of the occurrence of leishmaniasis outbreaks for the human population that occupies the location.INTRODUÇÃO: O estudo foi realizado com o objetivo de estudar a fauna de flebotomíneos (Diptera: Psychodidae e aspectos ligados à transmissão da leishmaniose tegumentar americana em uma área florestal com ocorrência de Leishmania (Leishmania amazonensis, situada no município de Bela Vista, Estado do Mato Grosso do Sul, Brasil. MÉTODOS: As capturas de flebotomíneos foram realizadas utilizando-se armadilhas tipo Disney modificadas, com isca roedor, Mesocricetus auratus, no período de maio de 2004 a janeiro de 2006. RESULTADOS: As coletas resultaram na identificação de 10 espécies de Phlebotominae: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni e Sciopemyia sordellii. As duas espécies predominantes foram Ev bourrouli, com 57,3% dos espécimes coletados, e Bi. flaviscutellata, representada por 41,4% e que esteve presente em todos os locais amostrados. Dois hamsters sentinelas adquiriram a infecção natural, sendo os isolados identificados como Leishmania amazonensis. CONCLUSÕES: Os resultados mostram a eficiência das armadilhas Disney para captura de Bichromomyia flaviscutellata, e a presença simultânea de ambos, o vetor e a espécie de Leishmania por ele transmitida pode ser considerada um fator preditor da ocorrência de leishmaniose para a população humana que permanecer nesse local.

  19. Sand fly captures with Disney traps in area of occurrence of Leishmania (Leishmania) amazonensis in the state of Mato Grosso do Sul, mid-western Brazil / Capturas de flebotomíneos com armadilhas de Disney em área de ocorrência de Leishmania (Leishmania) amazonensis no estado de Mato Grosso do Sul, região Centro-Oeste do Brasil

    Scientific Electronic Library Online (English)

    Maria Elizabeth Cavalheiros, Dorval; Tulia Peixoto, Alves; Geucira, Cristaldo; Hilda Carlos da, Rocha; Murilo Andrade, Alves; Elisa Teruya, Oshiro; Alessandra Gutierrez de, Oliveira; Reginaldo Peçanha, Brazil; Eunice Aparecida Bianchi, Galati; Rivaldo Venancio da, Cunha.

    2010-10-01

    Full Text Available INTRODUÇÃO: O estudo foi realizado com o objetivo de estudar a fauna de flebotomíneos (Diptera: Psychodidae) e aspectos ligados à transmissão da leishmaniose tegumentar americana em uma área florestal com ocorrência de Leishmania (Leishmania) amazonensis, situada no município de Bela Vista, Estado d [...] o Mato Grosso do Sul, Brasil. MÉTODOS: As capturas de flebotomíneos foram realizadas utilizando-se armadilhas tipo Disney modificadas, com isca roedor, Mesocricetus auratus, no período de maio de 2004 a janeiro de 2006. RESULTADOS: As coletas resultaram na identificação de 10 espécies de Phlebotominae: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni e Sciopemyia sordellii. As duas espécies predominantes foram Ev bourrouli, com 57,3% dos espécimes coletados, e Bi. flaviscutellata, representada por 41,4% e que esteve presente em todos os locais amostrados. Dois hamsters sentinelas adquiriram a infecção natural, sendo os isolados identificados como Leishmania amazonensis. CONCLUSÕES: Os resultados mostram a eficiência das armadilhas Disney para captura de Bichromomyia flaviscutellata, e a presença simultânea de ambos, o vetor e a espécie de Leishmania por ele transmitida pode ser considerada um fator preditor da ocorrência de leishmaniose para a população humana que permanecer nesse local. Abstract in english INTRODUCTION: The work was conducted to study phlebotomine fauna (Diptera: Psychodidae) and aspects of American cutaneous leishmaniasis transmission in a forested area where Leishmania (Leishmania) amazonensis occurs, situated in the municipality of Bela Vista, State of Mato Grosso do Sul, Brazil. M [...] ETHODS: The captures were conducted with modified Disney traps, using hamster (Mesocricetus auratus) as bait, from May 2004 to January 2006. RESULTS: Ten species of phlebotomine sandflies were captured: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni and Sciopemyia sordellii. The two predominant species were Ev bourrouli (57.3%) and Bi flaviscutellata (41.4%), present at all sampling sites. Two of the 36 hamsters used as bait presented natural infection with Leishmania. The parasite was identified as Leishmania (Leishmania) amazonensis. CONCLUSIONS: Analysis of the results revealed the efficiency of Disney traps for capturing Bichromomyia flaviscutellata and the simultaneous presence of both vector and the Leishmania species transmitted by the same can be considered a predictive factor of the occurrence of leishmaniasis outbreaks for the human population that occupies the location.

  20. Leishmania amazonensis exhibits phosphatidylserine-dependent procoagulant activity, a process that is counteracted by sandfly saliva

    Scientific Electronic Library Online (English)

    Natalia Cadaxo, Rochael; Luize Goncalves, Lima; Sandra Maria Pereira de, Oliveira; Marcello Andre, Barcinski; Elvira Maria, Saraiva; Robson Queiroz, Monteiro; Lucia Helena, Pinto-da-Silva.

    2013-09-01

    Full Text Available Leishmania parasites expose phosphatidylserine (PS) on their surface, a process that has been associated with regulation of host's immune responses. In this study we demonstrate that PS exposure by metacyclic promastigotes of Leishmania amazonensis favours blood coagulation. L. amazonensis accelera [...] tes in vitro coagulation of human plasma. In addition, L. amazonensis supports the assembly of the prothrombinase complex, thus promoting thrombin formation. This process was reversed by annexin V which blocks PS binding sites. During blood meal, Lutzomyia longipalpis sandfly inject saliva in the bite site, which has a series of pharmacologically active compounds that inhibit blood coagulation. Since saliva and parasites are co-injected in the host during natural transmission, we evaluated the anticoagulant properties of sandfly saliva in counteracting the procoagulant activity of L. amazonensis . Lu. longipalpis saliva reverses plasma clotting promoted by promastigotes. It also inhibits thrombin formation by the prothrombinase complex assembled either in phosphatidylcholine (PC)/PS vesicles or in L. amazonensis . Sandfly saliva inhibits factor X activation by the intrinsic tenase complex assembled on PC/PS vesicles and blocks factor Xa catalytic activity. Altogether our results show that metacyclic promastigotes of L. amazonensis are procoagulant due to PS exposure. Notably, this effect is efficiently counteracted by sandfly saliva.

  1. Leishmania amazonensis exhibits phosphatidylserine-dependent procoagulant activity, a process that is counteracted by sandfly saliva.

    Science.gov (United States)

    Rochael, Natalia Cadaxo; Lima, Luize Gonçalves; Oliveira, Sandra Maria Pereira de; Barcinski, Marcello André; Saraiva, Elvira Maria; Monteiro, Robson Queiroz; Pinto-da-Silva, Lucia Helena

    2013-09-01

    Leishmania parasites expose phosphatidylserine (PS) on their surface, a process that has been associated with regulation of host's immune responses. In this study we demonstrate that PS exposure by metacyclic promastigotes of Leishmania amazonensis favours blood coagulation. L. amazonensis accelerates in vitro coagulation of human plasma. In addition, L. amazonensis supports the assembly of the prothrombinase complex, thus promoting thrombin formation. This process was reversed by annexin V which blocks PS binding sites. During blood meal, Lutzomyia longipalpis sandfly inject saliva in the bite site, which has a series of pharmacologically active compounds that inhibit blood coagulation. Since saliva and parasites are co-injected in the host during natural transmission, we evaluated the anticoagulant properties of sandfly saliva in counteracting the procoagulant activity of L. amazonensis . Lu. longipalpis saliva reverses plasma clotting promoted by promastigotes. It also inhibits thrombin formation by the prothrombinase complex assembled either in phosphatidylcholine (PC)/PS vesicles or in L. amazonensis . Sandfly saliva inhibits factor X activation by the intrinsic tenase complex assembled on PC/PS vesicles and blocks factor Xa catalytic activity. Altogether our results show that metacyclic promastigotes of L. amazonensis are procoagulant due to PS exposure. Notably, this effect is efficiently counteracted by sandfly saliva. PMID:24037188

  2. Combined effect of the essential oil from Chenopodium ambrosioides and antileishmanial drugs on promastigotes of Leishmania amazonensis Efeito combinado do óleo de essência de Chenopodium ambrosioides e drogas anti-leishmaniose nos promastigotas de Leishmania amazonensis

    Directory of Open Access Journals (Sweden)

    Lianet Monzote

    2007-08-01

    Full Text Available To date, there are no vaccines against Leishmania, and chemotherapy remains the mainstay for the control of leishmaniasis. The drugs of choice used for leishmaniasis therapy are significantly toxic, expensive and with a growing frequency of refractory infections. Because of these limitations, a combination therapy is the better hope. This work demonstrates that the essential oil from Chenopodium ambrosioides shows a synergic activity after incubation in conjunction with pentamidine against promastigotes of Leishmania amazonensis. However, an indifferent effect has been found for combinations of meglumine antimoniate or amphotericin B and the essential oil.Até hoje não temos vacina contra a Leishmania e a quimioterapia é a indicação para o controle desta doença. Os remédios que hoje utilizamos são tóxicos e muito caros e além disso o resultado não é sempre o desejado. Por isso, uma terapia de combinação é a melhor opção. Este trabalho mostra que o óleo de essência de C. ambrosioides tem atividade sinérgica junto com a pentamidina sobre os promastigotas de L. amazonensis, diferente do resultado da combinação de antimônio de meglumine e anfotericina B e o óleo de essência.

  3. Combined effect of the essential oil from Chenopodium ambrosioides and antileishmanial drugs on promastigotes of Leishmania amazonensis / Efeito combinado do óleo de essência de Chenopodium ambrosioides e drogas anti-leishmaniose nos promastigotas de Leishmania amazonensis

    Scientific Electronic Library Online (English)

    Lianet, Monzote; Ana Margarita, Montalvo; Ramón, Scull; Migdalia, Miranda; Juan, Abreu.

    2007-08-01

    Full Text Available Até hoje não temos vacina contra a Leishmania e a quimioterapia é a indicação para o controle desta doença. Os remédios que hoje utilizamos são tóxicos e muito caros e além disso o resultado não é sempre o desejado. Por isso, uma terapia de combinação é a melhor opção. Este trabalho mostra que o óle [...] o de essência de C. ambrosioides tem atividade sinérgica junto com a pentamidina sobre os promastigotas de L. amazonensis, diferente do resultado da combinação de antimônio de meglumine e anfotericina B e o óleo de essência. Abstract in english To date, there are no vaccines against Leishmania, and chemotherapy remains the mainstay for the control of leishmaniasis. The drugs of choice used for leishmaniasis therapy are significantly toxic, expensive and with a growing frequency of refractory infections. Because of these limitations, a comb [...] ination therapy is the better hope. This work demonstrates that the essential oil from Chenopodium ambrosioides shows a synergic activity after incubation in conjunction with pentamidine against promastigotes of Leishmania amazonensis. However, an indifferent effect has been found for combinations of meglumine antimoniate or amphotericin B and the essential oil.

  4. A putative role for inosine 5' monophosphate dehydrogenase (IMPDH) in Leishmania amazonensis programmed cell death.

    Science.gov (United States)

    Pitaluga, A N; Moreira, M E C; Traub-Csekö, Y M

    2015-02-01

    Leishmania amazonensis undergoes apoptosis-like programmed cell death (PCD) under heat shock conditions. We identified a potential role for inosine 5' monophosphate dehydrogenase (IMPDH) in L.?amazonensis PCD. Trypanosomatids do not have a "de novo" purine synthesis pathway, relying on the salvage pathway for survival. IMPDH, a key enzyme in the purine nucleotide pathway, is related to cell growth and apoptosis. Since guanine nucleotide depletion triggers cell cycle arrest and apoptosis in several organisms we analyzed the correlation between IMPDH and apoptosis-like death in L.?amazonensis. The L.?amazonensis IMPDH inhibition effect on PCD was evaluated through gene expression analysis, mitochondrial depolarization and detection of Annexin-V labeled parasites. We demonstrated a down-regulation of impdh expression under heat shock treatment, which mimics the natural mammalian host infection. Also, IMPDH inhibitors ribavirin and mycophenolic acid (MPA) prevented cell growth and generated an apoptosis-like phenotype in sub-populations of L.?amazonensis promastigotes. Our results are in accordance with previous results showing that a subpopulation of parasites undergoes apoptosis-like cell death in the nutrient poor environment of the vector gut. Here, we suggest the involvement of purine metabolism in previously observed apoptosis-like cell death during Leishmania infection. PMID:25499513

  5. Therapeutic trial in experimental tegumentary leishmaniasis caused by Leishmania (Leishmania) amazonensis. A comparative study between mefloquine and aminosidine / Ensaio terapêutico na leishmaniose tegumentar experimental causada por Leishmania (Leishmania) amazonensis. Um estudo comparativo entre mefloquina e aminosidine

    Scientific Electronic Library Online (English)

    Letícia Oba, Galvão; Sebastião, Moreira Júnior; Pedro, Medeiros Júnior; Gleiser José Piantino, Lemos; Nara Fabiana, Cunha; Rosa Maria Parreiras, Antonino; Bráulio Silva, Santos Filho; Albino Verçosa, Magalhães.

    2000-08-01

    Full Text Available Foram utilizados 182 camundongos machos, isogênicos, da linhagem C57BL/6 inoculados na orelha direita com 3,0 x 10(6) formas promastigotas da cepa MHOM/BR/PH8 de Leishmania (Leishmania) amazonensis. Os animais foram separados em três grupos: 1) 52 animais tratados com mefloquina (16mg/kg/dia/10 dias [...] ), 2) 52 animais tratados com aminosidina [Paramomicina ®] (20mg/kg/dia/20 dias), 3) 78 animais controles, não manipulados. Vinte e seis animais de cada grupo tratado foram sacrificados nove e quinze semanas após a inoculação. Animais do grupo controle foram sacrificados na sexta, nona e décima quinta semanas após a inoculação. Ao final do tratamento, em relação à curva de peso da orelhas, somente nos animais tratados com aminosidina, houve nítida redução do peso em comparação com grupo controle. Na histopatologia verificou-se: a) não houve diferença entre o grupo tratado com mefloquina e o grupo controle; o grupo tratado com aminosidina, ao final do tratamento, teve menor infiltração por macrófagos vacuolizados; b) as avaliações da extensão das áreas de necrose e do nível da fibrose tecidual não mostraram diferenças entre os grupos tratados. Os animais do grupo controle apresentaram fibrose mais acentuada, seis semanas após o fim do tratamento. Pode-se concluir que ocorreu efeito terapêutico reduzido com a mefloquina e houve significativa melhora com a aminosidina. Entretanto, em todos os grupos as lesões não chegaram a curar. Abstract in english One hundred and eighty-two male inbred C57/BL/6 mice were infected with 3 x 106 Leishmania (Leishmania) amazonensis promastigotes of the MHOM/BR/PH8 strain by means of a subcutaneous injection in the right ear. The animals were separated in three groups: 1) oral mefloquine hydrochloride treatment (1 [...] 6mg/kg/day/10 days), 2) intramuscular aminosidine (Paromomycin®) treatment (20mg/kg/20 days) and 3) control. Twenty six mice of each treated group were sacrificed, one at the end of treatment (nine weeks after inoculation), and one six weeks later (fifteen weeks after inoculation). Control Group animals were sacrificed at weeks six, nine and fifteen after inoculation. There was no significant difference between Group 1 (mefloquine) and Group 3 (control) subjects. Group 2 animals (aminosidine) presented the smallest differences of all, both at the end of the treatment and six weeks later. The histopato-logical parameters have shown the following findings: a) there was no significant difference between the mefloquine treated group and the control group; the group treated with aminosidine showed fewer of vacuolated macrophages than the control group, at week 9 (end of treatment). b) both at the end of treatment and six weeks later, evaluation of tissue necrosis and tissue fibrosis revealed no differences between the treated groups. It was found that six weeks after the end of treatment, mice in the control group presented significantly more severe degrees of fibrosis than mice in the other groups. It can be concluded that mefloquine showed limited therapeutic effect in this experimental model, whereas aminosidine had a significant effect. Nevertheless, neither of them resulted in cure of the lesions.

  6. Therapeutic trial in experimental tegumentary leishmaniasis caused by Leishmania (Leishmania amazonensis. A comparative study between mefloquine and aminosidine Ensaio terapêutico na leishmaniose tegumentar experimental causada por Leishmania (Leishmania amazonensis. Um estudo comparativo entre mefloquina e aminosidine

    Directory of Open Access Journals (Sweden)

    Letícia Oba Galvão

    2000-08-01

    Full Text Available One hundred and eighty-two male inbred C57/BL/6 mice were infected with 3 x 106 Leishmania (Leishmania amazonensis promastigotes of the MHOM/BR/PH8 strain by means of a subcutaneous injection in the right ear. The animals were separated in three groups: 1 oral mefloquine hydrochloride treatment (16mg/kg/day/10 days, 2 intramuscular aminosidine (Paromomycin® treatment (20mg/kg/20 days and 3 control. Twenty six mice of each treated group were sacrificed, one at the end of treatment (nine weeks after inoculation, and one six weeks later (fifteen weeks after inoculation. Control Group animals were sacrificed at weeks six, nine and fifteen after inoculation. There was no significant difference between Group 1 (mefloquine and Group 3 (control subjects. Group 2 animals (aminosidine presented the smallest differences of all, both at the end of the treatment and six weeks later. The histopato-logical parameters have shown the following findings: a there was no significant difference between the mefloquine treated group and the control group; the group treated with aminosidine showed fewer of vacuolated macrophages than the control group, at week 9 (end of treatment. b both at the end of treatment and six weeks later, evaluation of tissue necrosis and tissue fibrosis revealed no differences between the treated groups. It was found that six weeks after the end of treatment, mice in the control group presented significantly more severe degrees of fibrosis than mice in the other groups. It can be concluded that mefloquine showed limited therapeutic effect in this experimental model, whereas aminosidine had a significant effect. Nevertheless, neither of them resulted in cure of the lesions.Foram utilizados 182 camundongos machos, isogênicos, da linhagem C57BL/6 inoculados na orelha direita com 3,0 x 10(6 formas promastigotas da cepa MHOM/BR/PH8 de Leishmania (Leishmania amazonensis. Os animais foram separados em três grupos: 1 52 animais tratados com mefloquina (16mg/kg/dia/10 dias, 2 52 animais tratados com aminosidina [Paramomicina ®] (20mg/kg/dia/20 dias, 3 78 animais controles, não manipulados. Vinte e seis animais de cada grupo tratado foram sacrificados nove e quinze semanas após a inoculação. Animais do grupo controle foram sacrificados na sexta, nona e décima quinta semanas após a inoculação. Ao final do tratamento, em relação à curva de peso da orelhas, somente nos animais tratados com aminosidina, houve nítida redução do peso em comparação com grupo controle. Na histopatologia verificou-se: a não houve diferença entre o grupo tratado com mefloquina e o grupo controle; o grupo tratado com aminosidina, ao final do tratamento, teve menor infiltração por macrófagos vacuolizados; b as avaliações da extensão das áreas de necrose e do nível da fibrose tecidual não mostraram diferenças entre os grupos tratados. Os animais do grupo controle apresentaram fibrose mais acentuada, seis semanas após o fim do tratamento. Pode-se concluir que ocorreu efeito terapêutico reduzido com a mefloquina e houve significativa melhora com a aminosidina. Entretanto, em todos os grupos as lesões não chegaram a curar.

  7. The T-cell anergy induced by Leishmania amazonensis antigens is related with defective antigen presentation and apoptosis

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    Roberta O. Pinheiro

    2004-09-01

    Full Text Available Leishmania amazonensis is the main agent of diffuse cutaneous leishmaniasis, a disease associated with anergic immune responses. In this study we show that the crude antigen of Leishmania amazonensis (LaAg but not L. braziliensis promastigotes (LbAg contains substances that suppress mitogenic and spontaneous proliferative responses of T cells. The suppressive substances in LaAg are thermoresistant (100ºC/1h and partially dependent on protease activity. T cell anergy was not due to a decreased production of growth factors as it was not reverted by addition of exogenous IL-2, IL-4, IFN-gamma or IL-12. LaAg did not inhibit anti-CD3-induced T cell activation, suggesting that anergy was due to a defect in antigen presentation. It was also not due to cell necrosis, but was accompanied by expressive DNA fragmentation in lymph node cells, indicative of apoptosis. Although pre-incubation of macrophages with LaAg prevented their capacity to present antigens, this effect was not due to apoptosis of the former. These results suggest that the T cell anergy found in diffuse leishmaniasis may be the result of parasite antigen-driven apoptosis of those cells following defective antigen presentation.A Leishmania amazonensis é o principal agente etiológico da leishmaniose cutânea difusa, uma doença associada a respostas imunes anérgicas. Neste estudo nós mostramos que o extrato bruto de promastigotas de Leishmania amazonensis (LaAg, mas não de L. braziliensis (LbAg, contém substâncias que suprimem respostas proliferativas, espontâneas e mitogênicas, de células T. As substâncias supressoras no LaAg são termo-resistentes (100°C/1h e parcialmente dependentes da atividade de proteases. A anergia de células T não foi devida à diminuição na produção de fatores de crescimento, uma vez que não foi revertida pela adição de: IL-2, IL-4, IFN-gama ou IL-12. O LaAg não inibiu a ativação de células T induzida por anti-CD3, sugerindo que a anergia é devida a um defeito na apresentação de antígenos. A anergia não foi devida à necrose celular, mas foi acompanhada de uma expressiva fragmentação de DNA nas células de linfonodos, indicativo de apoptose. Apesar da pré-incubação de macrófagos com LaAg ter inibido sua capacidade de apresentação de antigenos, este efeito não foi devido à apoptose dos primeiros. Estes resultados sugerem que a anergia de células T encontrada na leishmaniose difusa deve ser devida à apoptose dessas células que se segue à apresentação defeituosa de antígenos pelo antígeno do parasito.

  8. Immune responses induced by a Leishmania (Leishmania) amazonensis recombinant antigen in mice and lymphocytes from vaccinated subjects

    Scientific Electronic Library Online (English)

    Ana Paula, FERNANDES; Elizabeth, Cortez HERRERA; Wilson, MAYRINK; Ricardo, T. GAZZINELLI; Wen Yu, LIU; Carlos Alberto da, COSTA; Carlos Alberto Pereira, TAVARES; Maria Norma, MELO; Marilene Susan Marques, MICHALICK; Reiner, GENTZ; Evaldo, NASCIMENTO.

    1997-03-01

    Full Text Available A resposta imune induzida por uma proteína recombinante de Leishmania (Leishmania) amazonensis de 33 kD (Larp33) foi avaliada em linfócitos de indivíduos vacinados com a Leishvacin® e em camundongos através de vacinação. Larp33 foi expressa em Escherichia coli após clonagem de um fragmento genômico [...] de L. (L.) amazonensis de 2,2 kb no vetor pDS56-6His. Larp33 foi reconhecida por anticorpos IgG presentes no soro de indivíduos vacinados com Leishvacin® e induziu proliferação em linfócitos desses indivíduos em níveis comparáveis ao antígeno total de Leishmania. A análise por imunoblot indicou que Larp33 corresponde a uma proteína de aproximadamente 40 kD expressa em promastigotas de L. (L.) amazonensis e L. (Viannia) braziliensis. Hibridização com sonda de DNA correspondente a parte do fragmento clonado, também demonstrou que o gene codificador desta proteína é expresso em promastigotas destas duas espécies. Larp33 em associação com BCG (Bacille Calmette-Guerin) foi capaz de induzir 75% de proteção em camundongos C75BL/10 e BALB/c, suceptíveis à infecção por L. (L.) amazonensis. Linfócitos dos camundongos protegidos produziram IL-2 e IFN-g em resposta a Larp33. Nossos resultados indicam que Larp33 é imunogênica para linfócitos de indivíduos vacinados com Leishvacin ® e protetora para camundongos contra a infecção por L. (L.) amazonensis Abstract in english In the search for Leishmania recombinant antigens that can be used as a vaccine against American Cutaneous Leishmaniasis, we identified a Leishmania (Leishmania) amazonensis recombinant protein of 33 kD (Larp33) which is recognized by antibodies and peripheral blood leukocytes (PBL) from subjects va [...] ccinated with Leishvacin ®, Larp33 was expressed in Escherichia coli after cloning of a 2,2 kb Sau3A digested genomic fragment of L. (L.) amazonensis into the pDS56-6 His vector. Immunoblotting analysis indicated that Larp33 corresponds to an approximately 40-kD native protein expressed in promastigotes of L.(L.) amazonensis and L. (Viannia) braziliensis. Northern blots of total RNA also demonstrated that the gene coding for this protein is expressed in promastigotes of the major lineages of Leishmania causing American Cutaneous Leishmaniasis. Larp33 induced partial protection in susceptible mouse strains (BALB/c and C57BL/10) against L. (L.) amazonensis after vaccination using Bacille Calmette-Guerin (BCG) as adjuvant. In vitro stimulation of splenocytes from BALB/c protected mice with Larp33 elicited the secretion of IL-2 and IFN-g, suggesting that a Th1 cell-mediated protective response is associated with the resistance observed in these mice. As revealed by its immunogenic and antigenic properties, this novel recombinant antigen is a suitable candidate to compose a vaccine against cutaneous leishmaniasis

  9. Efficient synthesis of 16 aromatic Morita-Baylis-Hillman adducts: Biological evaluation on Leishmania amazonensis and Leishmania chagasi.

    Science.gov (United States)

    Junior, Cláudio G L; de Assis, Priscila A C; Silva, Fábio P L; Sousa, Suervy C O; de Andrade, Natália G; Barbosa, Ticiano P; Nerís, Patrícia L N; Segundo, Luiz V G; Anjos, Italo C; Carvalho, Gabriel A U; Rocha, Gerd B; Oliveira, Márcia R; Vasconcellos, Mário L A A

    2010-12-01

    Sixteen aromatic Morita-Baylis-Hillman adducts (MBHA) 1-16 were efficiently synthesized in a one step Morita-Baylis-Hillman reaction (MBHR) involving commercial aldehydes with methyl acrylate or acrylonitrile (81-100% yields) without the formation of side products on DABCO catalysis and at low temperature (0°C). The toxicities of these compounds were assessed against promastigote form of Leishmania amazonensis and Leishmania chagasi. The low synthetic cost of these MBHA, green synthetic protocols, easy one-step synthesis from commercially available and cheap reagents as well as the very good antileishmanial activity obtained for 14 and 16 (IC?? values of 6.88?gmL?¹ and 11.06?gmL?¹ respectively on L. amazonensis; 9.58?gmL?¹ and 14.34?gmL?¹ respectively on L. chagasi) indicates that these MBHA can be a novel and promising class of anti-parasitic compounds. PMID:20855101

  10. Correlation of meta 1 expression with culture stage, cell morphology and infectivity in Leishmania (Leishmania amazonensis promastigotes

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    Marcos Gonzaga dos Santos

    2011-03-01

    Full Text Available The parasitic protozoan Leishmania (Leishmania amazonensis alternates between mammalian and insect hosts. In the insect host, the parasites proliferate as procyclic promastigotes andthen differentiate into metacyclic infective forms. The meta 1 gene is preferentially expressed during metacyclogenesis. Meta 1 expression profile determination along parasite growth curves revealed that the meta 1 mRNA level peaked at the early stationary phase then decreased to an intermediate level. No correlation was observed between meta 1 expression and infectivity. Conversely, infectivity correlated with the increase of apoptotic cells in the late stationary phase.

  11. Correlation of meta 1 expression with culture stage, cell morphology and infectivity in Leishmania (Leishmania) amazonensis promastigotes

    Scientific Electronic Library Online (English)

    Marcos Gonzaga dos, Santos; Maria Fernanda Laranjeira da, Silva; Ricardo Andrade, Zampieri; Rafaella Marino, Lafraia; Lucile Maria, Floeter-Winter.

    2011-03-01

    Full Text Available The parasitic protozoan Leishmania (Leishmania) amazonensis alternates between mammalian and insect hosts. In the insect host, the parasites proliferate as procyclic promastigotes andthen differentiate into metacyclic infective forms. The meta 1 gene is preferentially expressed during metacyclogenes [...] is. Meta 1 expression profile determination along parasite growth curves revealed that the meta 1 mRNA level peaked at the early stationary phase then decreased to an intermediate level. No correlation was observed between meta 1 expression and infectivity. Conversely, infectivity correlated with the increase of apoptotic cells in the late stationary phase.

  12. Low and high-dose intradermal infection with Leishmania majorand Leishmania amazonensis in C57BL/6 mice

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    Denise Fonseca Côrtes

    2010-09-01

    Full Text Available A model of skin infection with Leishmania amazonensiswith low doses of parasites is compared to infection with high doses of L. amazonensis and low and high doses of Leishmania major. C57BL/6 mice were infected with 10³ or 10(6 parasites in the ear and the outcome of infection was assessed. The appearance of lesions in mice infected with 10³ parasites was delayed compared to mice infected with 10(6 Leishmania and parasites were detectable at the infection site before lesions became apparent. Mice infected with L. amazonensisdisplayed persistent lesions, whereas infection with L. major spontaneously healed in all groups, although lymphocytes persisted at the site of infection after healing. Macrophages persisted only in L. amazonensis-infected mice. High-dose L. amazonensis-infected mice produced lower levels of IFN-? and TNF than mice infected with L. major. No correlation between the persistence of parasites and IL-10 levels and the production of nitric oxide or urea by macrophages was found. We conclude that infection with low doses of L. amazonensisin the dermis changes the course of infection by delaying the appearance of lesions. However, low-dose infection does not change the outcomes of susceptibility and cytokine production described for subcutaneous infection with high numbers of parasites.

  13. Low and high-dose intradermal infection with Leishmania majorand Leishmania amazonensis in C57BL/6 mice

    Scientific Electronic Library Online (English)

    Denise Fonseca, Côrtes; Matheus Batista Heitor, Carneiro; Liliane Martins, Santos; Talita Correia de Oliveira, Souza; Tatiane Uceli, Maioli; Ana Luiza C, Duz; Maria Letícia, Ramos-Jorge; Luis Carlos Crocco, Afonso; Claudia, Carneiro; Leda Quercia, Vieira.

    2010-09-01

    Full Text Available A model of skin infection with Leishmania amazonensiswith low doses of parasites is compared to infection with high doses of L. amazonensis and low and high doses of Leishmania major. C57BL/6 mice were infected with 10³ or 10(6) parasites in the ear and the outcome of infection was assessed. The app [...] earance of lesions in mice infected with 10³ parasites was delayed compared to mice infected with 10(6) Leishmania and parasites were detectable at the infection site before lesions became apparent. Mice infected with L. amazonensisdisplayed persistent lesions, whereas infection with L. major spontaneously healed in all groups, although lymphocytes persisted at the site of infection after healing. Macrophages persisted only in L. amazonensis-infected mice. High-dose L. amazonensis-infected mice produced lower levels of IFN-? and TNF than mice infected with L. major. No correlation between the persistence of parasites and IL-10 levels and the production of nitric oxide or urea by macrophages was found. We conclude that infection with low doses of L. amazonensisin the dermis changes the course of infection by delaying the appearance of lesions. However, low-dose infection does not change the outcomes of susceptibility and cytokine production described for subcutaneous infection with high numbers of parasites.

  14. Daño ultraestructural del intestino medio abdominal de Lutzomyia ovallesi (Ortiz) (Diptera: Psychodidae) ocasionado por Leishmania (Leishmania) amazonensis / ULTRASTRUCTURAL DAMAGE TO THE MIDDLE INTESTINE OF Lutzomyia ovallesi (Ortiz) (DIPTERA: PSYCHODIDAE) CAUSED BY Leishmania (Leishmania) amazonensis

    Scientific Electronic Library Online (English)

    ELSA, NIEVES; DELSY, DÁVILA - VERA; ERNESTO, PALACIOS-PRÜ.

    2004-07-01

    Full Text Available Se estudió el intestino medio abdominal de Lutzomyia ovallesi infectada con Leishmania (Leishmania) amazonensis. Las hembras se observaron a los siete días post- infección, utilizando microscopía de luz de alta resolución y microscopía electrónica de transmisión. Se distinguieron dos tipos de célula [...] s epiteliales, células digestivas y células secretoras, en el intestino medio abdominal de L. ovallesi, tanto en los insectos controles como en flebotominos infectados. Los resultados muestran además, que L. ovallesi presentó alteraciones en la citoar-quitectura celular del intestino medio abdominal producto de la infección con L. (L.) amazonensis, observándose gran distensión del diámetro de la luz intestinal, degeneración de sus células, pérdida parcial o total de las microvellosidades y engrosamiento de la capa basal de toda la porción del intestino. Las células epiteliales presentaron degeneración vacuolar y mitocondrial y en la luz intestinal se observaron desechos epiteliales. El daño celular observado en el intestino medio abdominal de L. ovallesi, pueden tener relación con la secreción de lectinas y con la formación del gel observado, semejante a una matriz, en el lumen del intestino. Es necesario continuar los estudios para dilucidar aspectos importantes de la interrelación Leishmania-vector. Abstract in english A study was done in the middle intestine of Lutzomyia ovallesi infected with Leishmania (Leishmania) amzonensis. The females were examined seven days after infection by means of high resolution light microscopy and transmission electron microscopy. Two kinds of epithelial cells, digestive and secret [...] ory, were observed in the middle intestine of L. ovallesi, in both control insects and in those infected. Results showed changes in the cytoarchitecture of the intestine as a consequence of infection with L. (L.) amazonensis. There was a great increase in the diameter of the intestine, showing signs of cellular degeneration, such as partial or total loss of microvilli and the thickening of the basal layer of the whole portion of the intestine. Epithelial cells showed damage in vacuoles and mitochondria, and epithelial waste was observable in the intestine. Cellular damage in the middle intestine of L. ovallesi produced by infection with L. (L.) amazonensis is perhaps connected with lectin secretion and formation of gel, similar to that of a matrix, in the intestinal lumen. More studies are needed to clarify important aspects of the relationship between Leishmania and the vector.

  15. INTRACELLULAR Leishmania amazonensis KILLING INDUCED BY THE GUANINE NUCLEOSIDE 8-BROMOGUANOSINE

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    GIORGIO Selma

    1998-01-01

    Full Text Available In this study we investigated the effect of 8-Bromoguanosine, an immunostimulatory compound, on the cytotoxicity of macrophages against Leishmania amazonensis in an in vitro system. The results showed that macrophages treated with 8-Bromoguanosine before or after infection are capable to reduce parasite load, as monitored by the number of amastigotes per macrophage and the percentage of infected cells (i.e. phagocytic index. Since 8-Bromoguanosine was not directly toxic to the promastigotes, it was concluded that the ribonucleoside induced macrophage activation. Presumably, 8-Bromoguanosine primed macrophages by inducing interferon alpha and beta which ultimately led to L. amazonensis amastigote killing. The results suggest that guanine ribonucleosides may be useful to treat infections with intracellular pathogens.

  16. Mitochondria Superoxide Anion Production Contributes to Geranylgeraniol-Induced Death in Leishmania amazonensis

    OpenAIRE

    Celso Vataru Nakamura; Sueli de Oliveira Silva; Angelo de Oliveira Caleare; Tânia Ueda-Nakamura; Vânia Cristina Desoti; Milene Valéria Lopes

    2012-01-01

    Here we demonstrate the activity of geranylgeraniol, the major bioactive constituent from seeds of Bixa orellana, against Leishmania amazonensis. Geranylgeraniol was identified through 1H and 13C nuclear magnetic resonance imaging and DEPT. The compound inhibited the promastigote and intracellular amastigote forms, with IC50 of 11 ± 1.0 and 17.5 ± 0.7??g/mL, respectively. This compound was also more toxic to parasites than to macrophages and did not cause lysis in human blood cells. Morp...

  17. Chronic inflammatory response modulation against Leishmania (L.) amazonensis by homeopathic thymulin and antimonium crudum inBalb/c mice

    OpenAIRE

    Leoni Villano Bonamin; Marcia Dalastra Laurenti; Elizabeth Perez Hurtado; Lika Osugui; Cideli Paula Coelho; Thayna Neves Cardoso; Fabiana Rodrigues Santana

    2012-01-01

    In previous studies it was found that thymulin 5cH (thymic hormone) can modulate immune processes in several diseases. Additionally, the Antimonium crudum has used in dogs bearing leishmaniosis, according to the similia principle. We studied the inflammatory and immune modulation by thymulin 5CH and Antimonium crudum 30CH treatment in mice experimentally inoculated with Leishmania (L.) amazonensis. Male adult Balb/c mice were inoculated with Leishmania (2x105 promastigotes) into the footpad t...

  18. Experimental infection with Leishmania (Viannia) braziliensis, and Leishmania (Leishmania) amazonensis in the marmoset, Callithrix penicillata (Primates: Callithricidae)

    Scientific Electronic Library Online (English)

    César A. Cuba, Cuba; Vera, Ferreira; Maria, Bampi; Albino, Magalhães; Philip D., Marsden; Alejandro, Vexenat; Milton Thiago de, Mello.

    1990-12-01

    Full Text Available Foureen marmosets (Callithrix penicillata) were inoculated intradermally with promastigotes and/or amastigotes of Leishmania (Viannia) brazilensis (L. (V) b.) strains MHOM/BR/83/LTB-300MHOM/BR/85/LTB-12 MHOM/BR/81/LTB-179 and MHOM/BR/82/LTB-250. The evolution of subsequent lesions was studied for 15 [...] to 75 weeks post-inoculation (PI). All but of the L. (V) b. injected marmosets developed a cutaneous lesion at the point of inoculation after 3 to 9 weeks, characterized by the appearance of subcutaneous nodules containing parasites. parasites were isolated by culture (Difco Blood Agar) from all 11 positive animals. The maximum size of the lesions was variable and ranged between 37 mm² to 107 mm². Ulceration of primary nodules became evident after 3 to 12 weeks in all infected marmosets, but was faster and larger in 5 of the 11 animals. The active lesions persisted in 9 out of 11 Callithrix until the en of the observation period, which varied from 15-75 weeks. In 3 animals spontaneous healing of their lesions (13 to 25 weeks, PI) was observed buth with cryptic parasitism. In another 2 infected animals there was regression followed by reactivation of the cutaneous lesions. The appearance of smaller satellite lesions adjacent to primary ones, as well as metastatic lesions to the ear lobes, were documented in 2 animals. Promastigotes of L. (Leishmania) amazonensis (L.(L)a.) MHOM/BR/77/LTB-16 were inoculated in 1 marmoset. This animal remained chronically infected for 6 months and the lesions developed in a similar manner to L.(V)b. infected marmosets. No significant differences in clinical and parasitological behaviour were observed between promastigote or amastigote derived infections of the 2 species. Both produced chronic, long lasting lesions which eventually healed. The same was true for parameters of size and ulceration. Skin tests converted to parasite in 11 of 15 inected masmosets and in 10 of 12 parasite positive animnals. Moderate levels of circulating antibodies were also observed by IFAT /IgG assays. In spite of the failure to reproduce the mucosal form of the disease, an important aspect of the Callithrix model in experimental cutaneous leishmaniasis lies in the reproduction of 2 clinical events that are common in humans, namely, the chronic ulceration and spontaneous healing of the lesions.

  19. Experimental infection with Leishmania (Viannia braziliensis, and Leishmania (Leishmania amazonensis in the marmoset, Callithrix penicillata (Primates: Callithricidae

    Directory of Open Access Journals (Sweden)

    César A. Cuba Cuba

    1990-12-01

    Full Text Available Foureen marmosets (Callithrix penicillata were inoculated intradermally with promastigotes and/or amastigotes of Leishmania (Viannia brazilensis (L. (V b. strains MHOM/BR/83/LTB-300MHOM/BR/85/LTB-12 MHOM/BR/81/LTB-179 and MHOM/BR/82/LTB-250. The evolution of subsequent lesions was studied for 15 to 75 weeks post-inoculation (PI. All but of the L. (V b. injected marmosets developed a cutaneous lesion at the point of inoculation after 3 to 9 weeks, characterized by the appearance of subcutaneous nodules containing parasites. parasites were isolated by culture (Difco Blood Agar from all 11 positive animals. The maximum size of the lesions was variable and ranged between 37 mm² to 107 mm². Ulceration of primary nodules became evident after 3 to 12 weeks in all infected marmosets, but was faster and larger in 5 of the 11 animals. The active lesions persisted in 9 out of 11 Callithrix until the en of the observation period, which varied from 15-75 weeks. In 3 animals spontaneous healing of their lesions (13 to 25 weeks, PI was observed buth with cryptic parasitism. In another 2 infected animals there was regression followed by reactivation of the cutaneous lesions. The appearance of smaller satellite lesions adjacent to primary ones, as well as metastatic lesions to the ear lobes, were documented in 2 animals. Promastigotes of L. (Leishmania amazonensis (L.(La. MHOM/BR/77/LTB-16 were inoculated in 1 marmoset. This animal remained chronically infected for 6 months and the lesions developed in a similar manner to L.(Vb. infected marmosets. No significant differences in clinical and parasitological behaviour were observed between promastigote or amastigote derived infections of the 2 species. Both produced chronic, long lasting lesions which eventually healed. The same was true for parameters of size and ulceration. Skin tests converted to parasite in 11 of 15 inected masmosets and in 10 of 12 parasite positive animnals. Moderate levels of circulating antibodies were also observed by IFAT /IgG assays. In spite of the failure to reproduce the mucosal form of the disease, an important aspect of the Callithrix model in experimental cutaneous leishmaniasis lies in the reproduction of 2 clinical events that are common in humans, namely, the chronic ulceration and spontaneous healing of the lesions.

  20. Inhibition of Leishmania (Leishmania) amazonensis and Rat Arginases by Green Tea EGCG, (+)-Catechin and (?)-Epicatechin: A Comparative Structural Analysis of Enzyme-Inhibitor Interactions

    OpenAIRE

    dos Reis, Matheus Balduíno Goncalves; Manjolin, Letícia Correa; Maquiaveli, Claudia do Carmo; Santos-Filho, Osvaldo Andrade; da Silva, Edson Roberto

    2013-01-01

    Epigallocatechin-3-gallate (EGCG), a dietary polyphenol (flavanol) from green tea, possesses leishmanicidal and antitrypanosomal activity. Mitochondrial damage was observed in Leishmania treated with EGCG, and it contributed to the lethal effect. However, the molecular target has not been defined. In this study, EGCG, (+)-catechin and (?)-epicatechin were tested against recombinant arginase from Leishmania amazonensis (ARG-L) and rat liver arginase (ARG-1). The compounds inhibit ARG-L and A...

  1. Kinetoplastid membrane protein-11 exacerbates infection with Leishmania amazonensis in murine macrophages

    Scientific Electronic Library Online (English)

    Daniel Ignacchiti, Lacerda; Léa, Cysne-Finkelstein; Marise Pinheiro, Nunes; Paula Mello, De-Luca; Marcelo da Silva, Genestra; Leonor Laura Pinto, Leon; Marcia, Berrêdo-Pinho; Leila, Mendonça-Lima; Denise Cristina de Souza, Matos; Marco Alberto, Medeiros; Sergio Coutinho Furtado de, Mendonça.

    2012-03-01

    Full Text Available In Leishmania amazonensis, kinetoplastid membrane protein-11 (KMP-11) expression increases during metacyclogenesis and is higher in amastigotes than in promastigotes, suggesting a role for this protein in the infection of the mammalian host. We show that the addition of KMP-11 exacerbates L. amazone [...] nsis infection in peritoneal macrophages from BALB/c mice by increasing interleukin (IL)-10 secretion and arginase activity while reducing nitric oxide (NO) production. The doses of KMP-11, the IL-10 levels and the intracellular amastigote loads were strongly, positively and significantly correlated. The increase in parasite load induced by KMP-11 was inhibited by anti-KMP-11 or anti-IL-10 neutralising antibodies, but not by isotype controls. The neutralising antibodies, but not the isotype controls, were also able to significantly decrease the parasite load in macrophages cultured without the addition of KMP-11, demonstrating that KMP-11-induced exacerbation of the infection is not dependent on the addition of exogenous KMP-11 and that the protein naturally expressed by the parasite is able to promote it. In this study, the exacerbating effect of KMP-11 on macrophage infection with Leishmania is for the first time demonstrated, implicating it as a virulence factor in L. amazonensis. The stimulation of IL-10 production and arginase activity and the inhibition of NO synthesis are likely involved in this effect.

  2. Evaluation of Macroalgae Sulfated Polysaccharides on the Leishmania (L. amazonensis Promastigote

    Directory of Open Access Journals (Sweden)

    Marcos Hikari Toyama

    2013-03-01

    Full Text Available The sulfated polysaccharides from Solieria filiformis (Sf, Botryocladia occidentalis (Bo, Caulerpa racemosa (Cr and Gracilaria caudata (Gc were extracted and extensively purified. These compounds were then subjected to in vitro assays to evaluate the inhibition of these polysaccharides on the growth of Leishmania (L. amazonensis promastigotes. Under the same assay conditions, only three of the four sulfated polysaccharides were active against L. amazonensis, and the polysaccharide purified from Cr was the most potent (EC50 value: 34.5 ?g/mL. The polysaccharides derived from Bo and Sf demonstrated moderate anti-leishmanial activity (EC50 values of 63.7 ?g/mL and 137.4 ?g/mL. In addition, we also performed in vitro cytotoxic assays toward peritoneal macrophages and J774 macrophages. For the in vitro cytotoxicity assay employing J774 cells, all of the sulfated polysaccharides decreased cell survival, with CC50 values of 27.3 ?g/mL, 49.3 ?g/mL, 73.2 ?g/mL, and 99.8 ?g/mL for Bo, Cr, Gc, and Sf, respectively. However, none of the sulfated polysaccharides reduced the cell growth rate of the peritoneal macrophages. These results suggest that macroalgae contain compounds with various chemical properties that can control specific pathogens. According to our results, the assayed sulfated polysaccharides were able to modulate the growth rate and cell survival of Leishmania (L. amazonensis promastigotes in in vitro assays, and these effects involved the interaction of the sulfated polysaccharides on the cell membrane of the parasites.

  3. Understanding the mechanisms controlling Leishmania amazonensis infection in vitro: the role of LTB4 derived from human neutrophils.

    Science.gov (United States)

    Tavares, Natalia Machado; Araújo-Santos, Théo; Afonso, Lilian; Nogueira, Paula Monalisa; Lopes, Ulisses Gazos; Soares, Rodrigo Pedro; Bozza, Patrícia Torres; Bandeira-Melo, Christianne; Borges, Valeria Matos; Brodskyn, Cláudia

    2014-08-15

    Neutrophils are rapidly recruited to the site of Leishmania infection and play an active role in capturing and killing parasites. They are the main source of leukotriene B4 (LTB4), a potent proinflammatory lipid mediator. However, the role of LTB4 in neutrophil infection by Leishmania amazonensis is not clear. In this study, we show that L. amazonensis or its lipophosphoglycan can induce neutrophil activation, degranulation, and LTB4 production. Using pharmacological inhibitors of leukotriene synthesis, our findings reveal an LTB4-driven autocrine/paracrine regulatory effect. In particular, neutrophil-derived LTB4 controls L. amazonensis killing, degranulation, and reactive oxygen species production. In addition, L. amazonensis infection induces an early increase in Toll-like receptor 2 expression, which facilitates parasite internalization. Nuclear factor kappa B (NFkB) pathway activation represents a required upstream event for L. amazonensis-induced LTB4 synthesis. These leishmanicidal mechanisms mediated by neutrophil-derived LTB4 act through activation of its receptor, B leukotriene receptor 1 (BLT1). PMID:24634497

  4. Activity of the Lupane isolated from Combretum leprosum against Leishmania amazonensis promastigotes

    Scientific Electronic Library Online (English)

    Carolina B. G, Teles; Leandro S, Moreira; Alexandre de A. E, Silva; Valdir A, Facundo; Juliana P, Zuliani; Rodrigo G, Stábeli; Izaltina, Silva-Jardim.

    2011-05-01

    Full Text Available O presente trabalho descreve a atividade do extrato etanólico (EE) dos frutos de Combretum leprosum, do triterpeno 3?, 6?, 16?-triidroxilup-20(29)-eno (1) e seus derivados sintéticos (1a-1d), sobre promastigotas de Leishmaniaamazonensis. O EE apresentou atividade leishmanicida e o valor de IC50 foi [...] de 24,8 µg mL-1. Já o triterpeno 3?, 6?, 16?-trihidroxilup-20(29)-eno (1), na concentração de 5,0 µg mL-1, apresentou uma potente ação inibitória sobre a proliferação das promastigotas (IC50 = 3,3 µg mL-1). Entre os derivados sintéticos, apenas 1b e 1d apresentaram atividade contra as promastigotas (IC50 = 3,48 µg mL-1e 5,8 µg mL-1, respectivamente). Por outro lado, o derivado sintético 1a não apresentou atividade sobre as promastigotas de L. amazonensis. O EE, (1) e os derivados sintéticos 1a-1d não apresentaram efeito citotóxico sobre macrófagos peritoneais de camundongos. Estes resultados fornecem evidencias de que o extrato etanólico e o lupano isolado de C. leprosum possui atividade contra promastigotas de L. amazonensis, podendo ser utilizados como ferramentas no estudo de novas drogas leishmanicidas. Abstract in english This paper describes the activity of the ethanolic extract (EE), obtained from the fruits of Combretum leprosum, the triterpene 3?, 6?, 16?-trihydroxylup-20(29)-ene (1) and its synthetic derivatives 1a-1d on Leishmania amazonensis promastigotes. The EE displayed leishmanicidal activity and the IC50 [...] was 24.8 mg mL-1. However, the triterpene 3?, 6?, 16?-trihydroxylup-20(29)-ene (1), at a concentration of 5.0 mg mL-1, showed a potent inhibitory activity on promastigotes proliferation (IC50 = 3.3 mg mL-1). Among the synthetic derivatives, only (1b) and (1d) were active against promastigotes (IC50 = 3.48 mg mL-1and 5.8 mg mL-1, respectively). Moreover, the synthetic derivative 1a showed no activity on promastigotes of L. amazonensis. EE, (1) and the synthetic derivatives 1a-1d showed no cytotoxic effect on mice peritoneal macrophages. These results provide evidence that the ethanolic extract and the lupane isolated from C. leprosum was active against promastigotes of L. amazonensis, and may be used as a tool in the studies of new antileishmanial drugs.

  5. In vitro activity of the hydroethanolic extract and biflavonoids isolated from Selaginella sellowii on Leishmania (Leishmania) amazonensis

    Scientific Electronic Library Online (English)

    Yasmin Silva, Rizk; Alice, Fischer; Marillin de Castro, Cunha; Patrik Oening, Rodrigues; Maria Carolina Silva, Marques; Maria de Fátima Cepa, Matos; Mônica Cristina Toffoli, Kadri; Carlos Alexandre, Carollo; Carla Cardozo Pinto de, Arruda.

    1050-10-01

    Full Text Available This study is the first phytochemical investigation of Selaginella sellowii and demonstrates the antileishmanial activity of the hydroethanolic extract from this plant (SSHE), as well as of the biflavonoids amentoflavone and robustaflavone, isolated from this species. The effects of these substances [...] were evaluated on intracellular amastigotes of Leishmania (Leishmania) amazonensis, an aetiological agent of American cutaneous leishmaniasis. SSHE was highly active against intracellular amastigotes [the half maximum inhibitory concentration (IC50) = 20.2 µg/mL]. Fractionation of the extract led to the isolation of the two bioflavonoids with the highest activity: amentoflavone, which was about 200 times more active (IC50 = 0.1 ?g/mL) and less cytotoxic than SSHE (IC50 = 2.2 and 3 ?g/mL, respectively on NIH/3T3 and J774.A1 cells), with a high selectivity index (SI) (22 and 30), robustaflavone, which was also active against L. amazonensis (IC50 = 2.8 µg/mL), but more cytotoxic, with IC50 = 25.5 µg/mL (SI = 9.1) on NIH/3T3 cells and IC50 = 3.1 µg/mL (SI = 1.1) on J774.A1 cells. The production of nitric oxide (NO) was lower in cells treated with amentoflavone (suggesting that NO does not contribute to the leishmanicidal mechanism in this case), while NO release was higher after treatment with robustaflavone. S. sellowii may be a potential source of biflavonoids that could provide promising compounds for the treatment of cutaneous leishmaniasis.

  6. Entry and survival of Leishmania amazonensis amastigotes within phagolysosome-like vacuoles that shelter Coxiella burnetii in Chinese hamster ovary cells.

    OpenAIRE

    Veras, P S; Moulia, C.; Dauguet, C; Tunis, C T; Thibon, M; Rabinovitch, M

    1995-01-01

    Coxiella burnetii, a rickettsia, and Leishmania amazonensis, a protozoan flagellate, lodge in their host cells within large phagolysosome-like vacuoles. In the present study, C. burnetii-infected Vero or CHO cells were superinfected with L. amazonensis amastigotes to determine if these parasites can home to and survive within heterologous vacuoles. Six hours after superinfection, Leishmania amastigotes were located almost exclusively within large Coxiella-containing vacuoles. Thereafter, the ...

  7. Isolation of an enriched plasma membrame subpellicular microtubule fraction of Leishmania mexicana amazonensis

    Scientific Electronic Library Online (English)

    Solange L., Timm; Leonor L., Leon; Neize M., Pereira; Wanderley de, Souza; M. Queiroz, Cruz; Helena M., Bräscher; A. Oliveira, Lima.

    Full Text Available Um método de fracionamento subcelular, previamente desenvolvido para Trypanosoma cruzi, foi aplicado para isolar a membrana plasmática de promastigotas de Leishmania mexicana amazonensis. As células, após turgimento em meio hipotônico, foram rompidas na presença de um detergente não iônico e a fraç [...] ão de membrana isolada por centrifugação diferencial. A microscopia eletrônica mostrou consistir a fração de fragmentos de membrana plasmática associados com microtúbulos subpeliculares. Foi também mostrado que esta fração era capaz de induzir resposta celular em camundongos. Abstract in english A cell fractionation procedure previously developed for Trypanosoma cruzi was applied to isolated the plasma membrane of promastigotes of Leishania mexicana amazonensis. The cell, swollen in an hypotonic mediun, were disrupted in the presence of a nonionic detergent and the membrane fraction isolat [...] ed by differencial centrifugation. Electron microscopy showed that the fraction consisted of pieces of the plasma membrane associated with subpellicular microtubules. It was also shown that this fraction is able to induce cell-mediated immune response in mice.

  8. Transcriptional signatures of BALB/c mouse macrophages housing multiplying Leishmania amazonensis amastigotes

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    Lang Thierry

    2009-03-01

    Full Text Available Abstract Background Mammal macrophages (M? display a wide range of functions which contribute to surveying and maintaining tissue integrity. One such function is phagocytosis, a process known to be subverted by parasites like Leishmania (L. Indeed, the intracellular development of L. amazonensis amastigote relies on the biogenesis and dynamic remodelling of a phagolysosome, termed the parasitophorous vacuole, primarily within dermal M?. Results Using BALB/c mouse bone marrow-derived M? loaded or not with amastigotes, we analyzed the transcriptional signatures of M? 24 h later, when the amastigote population was growing. Total RNA from M? cultures were processed and hybridized onto Affymetrix Mouse430_2 GeneChips®, and some transcripts were also analyzed by Real-Time quantitative PCR (RTQPCR. A total of 1,248 probe-sets showed significant differential expression. Comparable fold-change values were obtained between the Affymetrix technology and the RTQPCR method. Ingenuity Pathway Analysis software® pinpointed the up-regulation of the sterol biosynthesis pathway (p-value = 1.31e-02 involving several genes (1.95 to 4.30 fold change values, and the modulation of various genes involved in polyamine synthesis and in pro/counter-inflammatory signalling. Conclusion Our findings suggest that the amastigote growth relies on early coordinated gene expression of the M? lipid and polyamine pathways. Moreover, these M? hosting multiplying L. amazonensis amastigotes display a transcriptional profile biased towards parasite-and host tissue-protective processes.

  9. Mitochondria Superoxide Anion Production Contributes to Geranylgeraniol-Induced Death in Leishmania amazonensis.

    Science.gov (United States)

    Lopes, Milene Valéria; Desoti, Vânia Cristina; Caleare, Angelo de Oliveira; Ueda-Nakamura, Tânia; Silva, Sueli Oliveira; Nakamura, Celso Vataru

    2012-01-01

    Here we demonstrate the activity of geranylgeraniol, the major bioactive constituent from seeds of Bixa orellana, against Leishmania amazonensis. Geranylgeraniol was identified through (1)H and (13)C nuclear magnetic resonance imaging and DEPT. The compound inhibited the promastigote and intracellular amastigote forms, with IC(50) of 11 ± 1.0 and 17.5 ± 0.7??g/mL, respectively. This compound was also more toxic to parasites than to macrophages and did not cause lysis in human blood cells. Morphological and ultrastructural changes induced by geranylgeraniol were observed in the protozoan by electronic microscopy and included mainly mitochondria alterations and an abnormal chromatin condensation in the nucleus. These alterations were confirmed by Rh 123 and TUNEL assays. Additionally, geranylgeraniol induces an increase in superoxide anion production. Collectively, our in vitro studies indicate geranylgeraniol as a selective antileishmanial that appears to be mediated by apoptosis-like cell death. PMID:23304195

  10. Cell populations in lesions of cutaneous leishmaniasis of leishmania (L.) amazonensis- infected rhesus macaques, Macaca mulatta

    Scientific Electronic Library Online (English)

    VF, Amaral; C, Pirmez; AJS, Gonçalves; V, Ferreira; G, Grimaldi Jr.

    2000-04-01

    Full Text Available The cellular nature of the infiltrate in cutaneous lesion of rhesus monkeys experimentally infected with Leishmania (L.) amazonensis was characterized by immunohistochemistry. Skin biopsies from infected animals with active or healing lesions were compared to non-infected controls (three of each typ [...] e) to quantitate inflammatory cell types. Inflammatory cells (composed of a mixture of T lymphocyte subpopulations, macrophages and a small number of natural killer cells and granulocytes) were more numerous in active lesions than in healing ones. T-cells accounted for 44.7 ± 13.1% of the infiltrate in active lesions (versus CD2+= 40.3 ± 5.7% in healing lesions) and T-cell ratios favor CD8+ cells in both lesion types. The percentage of cells expressing class II antigen (HLA-DR+) in active lesions (95 ± 7.1%) was significantly higher (P

  11. Inmunización con subgenoteca de Leishmania amazonensis protege contra el reto a ratones BALB/c

    Scientific Electronic Library Online (English)

    Ana M, Montalvo Álvarez; Lianet, Monzote Fidalgo; Lisset, Fonseca Géigel; Ivón, Montano Goodridge; Luis, Fonte Galindo; Manuel, Soto.

    2004-08-01

    Full Text Available Se construyó una genoteca de Leishmania amazonensis en vector de expresión en células eucariotas (pEF1HisA, pEF1HisB, pEF1HisC). Se prepararon 2 subgenotecas con un número aproximado de 500 clones cada una y ratones BALB/c fueron inmunizados con 50 mg/0,1 mL de ADN de cada una; 2 inmunizaciones por [...] vía IM, con 15 d de intervalo fueron realizadas. Grupos de ratones controles fueron inmunizados con ADN del plásmido vacío, con antígeno soluble del parásito (100 mg/0,1 mL) y solución salina fisiológica. Se midió el tamaño de las lesiones durante 12 semanas y al final del experimento, la carga parasitaria en los sitios de lesión fue determinada por el método de microtitulación en placas. Los ratones inmunizados con ADN 1, controlaron el tamaño de las lesiones, así como también los inmunizados con antígenos solubles, lo que alcanzó diferencia estadística (p Abstract in english A genomic library of Leishmania amazonensis in expression vector of eukaryote cells (pEF1HisA, pEF1HisB, pEF1HisC) was prepared. Also two subgenomic libraries having each 500 clones approximately were created and BALB/c mice were immunized with 50 mg/0,1 mL of DNA from each. Two immunizations were a [...] dministered intramuscularly at 15-day interval. Groups of control mice were immunized with DNA from empty plasmid pEF1His, with soluble parasite antigen (100 mg/0,1 mL) and saline solution. The size of lesions was measured for 12 weeks and at the end of the experiment, the parasite load at lesion sites was determined by plaque microtitration method. In mice immunized with subgenomic library DNA1 and with soluble antigens,the size of lesions was controlled, which reached an statistical difference (p

  12. Effect of extracts and isolated compounds from Chresta scapigera on viability of Leishmania amazonensis and Trypanosoma cruzi / Efeito dos extratos e compostos isolados de Chresta scapigera sobre a viabilidade de Leishmania amazonensis e Trypanosoma cruzi

    Scientific Electronic Library Online (English)

    Elisandra Cristina, Schinor; Marcos José, Salvador; Elisabeth Mieko Furusho, Pral; Silvia Celina, Alfieri; Sérgio, Albuquerque; Diones Aparecida, Dias.

    2007-06-01

    Full Text Available O fracionamento dos extratos bioativos de Chresta scapigera proporcionou o isolamento de triterpenos e flavonóides, dentre os quais acetato de beta-amirina (1), acetate de 11alfa,12-oxidotaraxeril (2) e lupeol (3), assim como os flavonóides apigenina (6), caenferol (7), crisoeriol (8) e luteolina (9 [...] ) mostraram-se ativos contra formas amastigotas de Leishmania amazonensis, enquanto, apenas os flavonóides (6), (7) e (9) apresentaram toxicidade contra as formas tripomastigotas de Trypanosoma cruzi. Abstract in english Fractionation of bioactive crude extracts of Chresta scapigera led to the isolation of four triterpenes and five flavonoids, among them beta-amyrin acetate (1), 11alpha,12alpha-oxidetaraxeryl acetate (2) and lupeol (3), as well as the flavonoids apigenin (6), kaempferol (7), crysoeriol (8) and luteo [...] lin (9) were active against Leishmania amazonensis amastigotes-like stages, while only the flavonoids (6), (7) and (9) showed toxicity towards bloods trypomastigote forms of Trypanosoma cruzi.

  13. The action of ionizing radiation on the morphology, physiology and growth of Leishmania Amazonensis, with evaluation of their immunogenic power in experimental models; Acao da radiacao ionizante sobre a morfologia, fisiologia e crescimento da Leishmania amazonensis, com avaliacao de seu poder imunogenico em modelos experimentais

    Energy Technology Data Exchange (ETDEWEB)

    Bonetti, Franco Claudio

    2002-07-01

    Leishmaniasis is a disease which affects thousands of people in the Tropical regions around the world, is caused by a protozoan of the genus Leishmania spp., with urban and wild mammals acting as reservoirs. In the mammal host, the amastigote form of the parasite infects and multiplies into macrophages. Treatments for leishmaniasis have a high cost and are long lasting, frequently resulting in therapy interruption. This procedure culminates with a selection of resistant parasite strains, inducing tolerance to the therapy. Either the control of vectors or the mammal host are difficult due the social and economic implications. Thus, the search for alternatives treatments against these protozoans have been stimulated. The gamma radiation ({sup 60}CO) shown to be an efficient toll to kill these parasites maintaining their immunogenicity. Cellular viability, Electronically microscopy and Multiplex-PCR techniques showed that, after irradiation, the parasites had their growth inhibited by cytoplasmatic and nucleic material disorganisation, appointing the gamma radiation as important in terms of immunogens improvement. (author)

  14. Inmunización con subgenoteca de Leishmania amazonensis protege contra el reto a ratones BALB/c

    Directory of Open Access Journals (Sweden)

    Ana M Montalvo Álvarez

    2004-08-01

    Full Text Available Se construyó una genoteca de Leishmania amazonensis en vector de expresión en células eucariotas (pEF1HisA, pEF1HisB, pEF1HisC. Se prepararon 2 subgenotecas con un número aproximado de 500 clones cada una y ratones BALB/c fueron inmunizados con 50 mg/0,1 mL de ADN de cada una; 2 inmunizaciones por vía IM, con 15 d de intervalo fueron realizadas. Grupos de ratones controles fueron inmunizados con ADN del plásmido vacío, con antígeno soluble del parásito (100 mg/0,1 mL y solución salina fisiológica. Se midió el tamaño de las lesiones durante 12 semanas y al final del experimento, la carga parasitaria en los sitios de lesión fue determinada por el método de microtitulación en placas. Los ratones inmunizados con ADN 1, controlaron el tamaño de las lesiones, así como también los inmunizados con antígenos solubles, lo que alcanzó diferencia estadística (pA genomic library of Leishmania amazonensis in expression vector of eukaryote cells (pEF1HisA, pEF1HisB, pEF1HisC was prepared. Also two subgenomic libraries having each 500 clones approximately were created and BALB/c mice were immunized with 50 mg/0,1 mL of DNA from each. Two immunizations were administered intramuscularly at 15-day interval. Groups of control mice were immunized with DNA from empty plasmid pEF1His, with soluble parasite antigen (100 mg/0,1 mL and saline solution. The size of lesions was measured for 12 weeks and at the end of the experiment, the parasite load at lesion sites was determined by plaque microtitration method. In mice immunized with subgenomic library DNA1 and with soluble antigens,the size of lesions was controlled, which reached an statistical difference (p< 0,05 in relation to the rest of groups whose lesions increased. The parasite load found in lesion sites confirmed the previous results; the number of promastigots was significantly lower in those mice already protected. It was concluded that in subgenomic library DNA1 there should be genes or gene fragments whose in vivo expression induces protective immune response against the challenge in the murine model used

  15. 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

    Scientific Electronic Library Online (English)

    Patrícia Shima, Luize; Tatiana Shioji, Tiuman; Luis Gustavo, Morello; Paloma Korehiza, Maza; Tânia, Ueda-Nakamura; Benedito Prado, Dias Filho; Diógenes Aparício Garcia, Cortez; João Carlos Palazzo de, Mello; Celso Vataru, Nakamura.

    2005-03-01

    Full Text Available 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. Abstract in english 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 Trypano [...] soma 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.

  16. DNA sequencing confirms the involvement of Leishmania (L. amazonensis in american tegumentary leishmaniasis in the state of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Angela Rapela Medeiros

    2008-01-01

    Full Text Available INTRODUCTION: American tegumentary leishmaniasis (ATL represents one of the most important public health issues in the world. An increased number of autochthonous cases of ATL in the Northeastern region of São Paulo State has been documented in the last few years, leading to a desire to determine the Leishmania species implicated. METHODS: PCR followed by DNA sequencing was carried out to identify a 120bp fragment from the universal kDNA minicircle of the genus Leishmania in 61 skin or mucosal biopsies from patients with ATL. RESULTS: DNA sequencing permitted the identification of a particular 15bp fragment (5' …GTC TTT GGG GCA AGT... 3' in all samples. Analysis by the neighbor-joining method showed the occurrence of two distinct groups related to the genus Viannia (V and Leishmania (L, each with two subgroups. Autochthonous cases with identity to a special Leishmania sequence not referenced in Genbank predominated in subgroup V.1, suggesting the possible existence of a subtype or mutation of Leishmania Viannia in this region. In the subgroup L.2, which showed identity with a known sequence of L. (L. amazonensis, there was a balanced distribution of autochthonous and non-autochthonous cases, including the mucosal and mucocutaneus forms in four patients. The last observation may direct us to new concepts, since the mucosal compromising has commonly been attributed to L. (V. braziliensis, even though L. (L. amazonensis is more frequent in the Amazonian region. CONCLUSIONS: These results confirm the pattern of distribution and possible mutations of these species, as well as the change in the clinical form presentation of ATL in the São Paulo State.

  17. DNA sequencing confirms the involvement of Leishmania (L.) amazonensis in american tegumentary leishmaniasis in the state of São Paulo, Brazil

    Scientific Electronic Library Online (English)

    Angela Rapela, Medeiros; Wilson A, Silva Jr; Ana Maria, Roselino.

    Full Text Available INTRODUCTION: American tegumentary leishmaniasis (ATL) represents one of the most important public health issues in the world. An increased number of autochthonous cases of ATL in the Northeastern region of São Paulo State has been documented in the last few years, leading to a desire to determine t [...] he Leishmania species implicated. METHODS: PCR followed by DNA sequencing was carried out to identify a 120bp fragment from the universal kDNA minicircle of the genus Leishmania in 61 skin or mucosal biopsies from patients with ATL. RESULTS: DNA sequencing permitted the identification of a particular 15bp fragment (5' …GTC TTT GGG GCA AGT... 3') in all samples. Analysis by the neighbor-joining method showed the occurrence of two distinct groups related to the genus Viannia (V) and Leishmania (L), each with two subgroups. Autochthonous cases with identity to a special Leishmania sequence not referenced in Genbank predominated in subgroup V.1, suggesting the possible existence of a subtype or mutation of Leishmania Viannia in this region. In the subgroup L.2, which showed identity with a known sequence of L. (L.) amazonensis, there was a balanced distribution of autochthonous and non-autochthonous cases, including the mucosal and mucocutaneus forms in four patients. The last observation may direct us to new concepts, since the mucosal compromising has commonly been attributed to L. (V.) braziliensis, even though L. (L.) amazonensis is more frequent in the Amazonian region. CONCLUSIONS: These results confirm the pattern of distribution and possible mutations of these species, as well as the change in the clinical form presentation of ATL in the São Paulo State.

  18. Experimental infection with Leishmania (Viannia) braziliensis, and Leishmania (Leishmania) amazonensis in the marmoset, Callithrix penicillata (Primates: Callithricidae)

    OpenAIRE

    Cuba Cuba, Ce?sar A.; Vera Ferreira; Maria Bampi; Albino Magalhães; Marsden, Philip D.; Alejandro Vexenat; Milton Thiago Mello

    1990-01-01

    Foureen marmosets (Callithrix penicillata) were inoculated intradermally with promastigotes and/or amastigotes of Leishmania (Viannia) brazilensis (L. (V) b.) strains MHOM/BR/83/LTB-300MHOM/BR/85/LTB-12 MHOM/BR/81/LTB-179 and MHOM/BR/82/LTB-250. The evolution of subsequent lesions was studied for 15 to 75 weeks post-inoculation (PI). All but of the L. (V) b. injected marmosets developed a cutaneous lesion at the point of inoculation after 3 to 9 weeks, characterized by the appearance of subcu...

  19. Identification of SL addition trans-splicing acceptor sites in the internal transcribed spacer I region of pre-rRNA in Leishmania (Leishmania) amazonensis

    Scientific Electronic Library Online (English)

    Mario Gustavo, Mayer; Lucile Maria, Floeter-Winter.

    1070-10-01

    Full Text Available Trypanosomatidae is a family of early branching eukaryotes harbouring a distinctive repertoire of gene expression strategies. Functional mature messenger RNA is generated via the trans-splicing and polyadenylation processing of constitutively transcribed polycistronic units. Recently, trans-splicing [...] of pre-small subunit ribosomal RNA in the 5' external transcribed spacer region and of precursor tRNAsec have been described. Here, we used a previously validated semi-nested reverse transcription-polymerase chain reaction strategy to investigate internal transcribed spacer (ITS) I acceptor sites in total RNA from Leishmania (Leishmania) amazonensis. Two distinct spliced leader-containing RNAs were detected indicating that trans-splicing reactions occur at two AG acceptor sites mapped in this ITS region. These data provide further evidence of the wide spectrum of RNA molecules that act as trans-splicing acceptors in trypanosomatids.

  20. Effect of Apigenin on Leishmania amazonensis Is Associated with Reactive Oxygen Species Production Followed by Mitochondrial Dysfunction.

    Science.gov (United States)

    Fonseca-Silva, Fernanda; Canto-Cavalheiro, Marilene M; Menna-Barreto, Rubem F S; Almeida-Amaral, Elmo E

    2015-04-24

    Leishmaniasis is an important neglected disease caused by protozoa of the genus Leishmania that affects more than 12 million people worldwide. Leishmaniasis treatment requires the administration of toxic and poorly tolerated drugs, and parasite resistance greatly reduces the efficacy of conventional medications. Apigenin (1), a naturally occurring plant flavone, has a wide range of reported biological effects. In this study, antileishmanial activity of 1 in vitro was investigated, and its mechanism of action against Leishmania amazonensis promastigotes was described. Treatment with 1 for 24 h resulted in concentration-dependent inhibition of cellular proliferation (IC50 = 23.7 ?M) and increased reactive oxygen species (ROS) generation. Glutathione and N-acetyl-l-cysteine protected L. amazonensis from the effects of 1 and reduced ROS levels after the treatment. By contrast, oxidized glutathione did not reduce the levels of ROS caused by 1 by not preventing the proliferation inhibition. Apigenin 1 also induced an extensive swelling in parasite mitochondria, leading to an alteration of the mitochondrial membrane potential, rupture of the trans-Golgi network, and cytoplasmic vacuolization. These results demonstrate the leishmanicidal effect of 1 and suggest the involvement of ROS leading to mitochondrial collapse as part of the mechanism of action. PMID:25768915

  1. Leishmania amazonensis promastigotes in 3D Collagen I culture: an in vitro physiological environment for the study of extracellular matrix and host cell interactions

    Directory of Open Access Journals (Sweden)

    Debora B. Petropolis

    2014-04-01

    Full Text Available Leishmania amazonensis is the causative agent of American cutaneous leishmaniasis, an important neglected tropical disease. Once Leishmania amazonensis is inoculated into the human host, promastigotes are exposed to the extracellular matrix (ECM of the dermis. However, little is known about the interaction between the ECM and Leishmania promastigotes. In this study we established L. amazonensis promastigote culture in a three-dimensional (3D environment mainly composed of Collagen I (COL I. This 3D culture recreates in vitro some aspects of the human host infection site, enabling the study of the interaction mechanisms of L. amazonensis with the host ECM. Promastigotes exhibited “freeze and run” migration in the 3D COL I matrix, which is completely different from the conventional in vitro swimming mode of migration. Moreover, L. amazonensis promastigotes were able to invade, migrate inside, and remodel the 3D COL I matrix. Promastigote trans-matrix invasion and the freeze and run migration mode were also observed when macrophages were present in the matrix. At least two classes of proteases, metallo- and cysteine proteases, are involved in the 3D COL I matrix degradation caused by Leishmania. Treatment with a mixture of protease inhibitors significantly reduced promastigote invasion and migration through this matrix. Together our results demonstrate that L. amazonensis promastigotes release proteases and actively remodel their 3D environment, facilitating their migration. This raises the possibility that promastigotes actively interact with their 3D environment during the search for their cellular “home”—macrophages. Supporting this hypothesis, promastigotes migrated faster than macrophages in a novel 3D co-culture model.

  2. Construcción de una biblioteca genómica de Leishmania amazonensis y su expresión en músculo de ratones BALB/c

    Scientific Electronic Library Online (English)

    Ana Margarita, Montalvo Álvarez; Esteban, Alberti Amador; Marta M., González Elías; Rocío, García Miniet; María E., Sarmiento García; Armando, Acosta Domínguez.

    2001-12-01

    Full Text Available Se construyó una biblioteca genómica de Leishmania amazonensis mediante el vector pcDNA3, con promotor de expresión en células eucariotas, con el objetivo de contribuir a la aplicación de la tecnología de inmunización con ácidos nucleicos en la leishmaniosis. Para demostrar la expresión de la genote [...] ca en el músculo de ratones inmunizados con esta, se realizó la técnica de inmunofluorescencia indirecta. Como anticuerpo primario se utilizó una mezcla de sueros con alto título antileishmania, de una zona donde predomina la infección con L. braziliensis. Se obtuvo una biblioteca con 80 % de clones recombinantes. Se demostró la expresión de determinantes antigénicos en el músculo de ratones BALB/c inmunizados, según resultados de la inmunofluorescencia. Abstract in english A genomic library of Leishaminia amazonensis was built through a pcDNA3 vector, with expression promoter in eukaryot cells, to contribute to the application of immunization technology with nucleic acids in leishmaniasis. To show the expression genomic library in the muscles of mice immunized with it [...] , the indirect immunofluoresce technique was used. A mix of sera with high antileishmania titers from an area where L.braziliensis infection is predominant was used as primary antibody. A library of 80% recombinant clones was obtained. Antigen determinant expression was confirmed in immunized BALB/c mice´s muscles, according to the results of immunofluorescence testing.

  3. In vitro and in vivo activity of meglumine antimoniate produced at Farmanguinhos-Fiocruz, Brazil, against Leishmania (Leishmania) amazonensis, L (L.) chagasi and L (Viannia) braziliensis

    Scientific Electronic Library Online (English)

    Eliane de, Morais-Teixeira; Alcione S de, Carvalho; Jorge CS da, Costa; Silvio L, Duarte; Jorge S, Mendonça; Núbia, Boechat; Ana, Rabello.

    2008-06-01

    Full Text Available The leishmanicidal activity of four batches of meglumine antimoniate, produced in Farmanguinhos-Fiocruz, Brazil (TAMs), was assessed and compared to Glucantime®-Aventis Pharma Ltda. Using the amastigote-like in vitro model, the active concentrations of Sb v varied from 10µg/ml to 300 µg/ml for L. (L [...] .) chagasi and from 50µg/ml to 300µg/ml for L. (L.) amazonensis, with no statistically significant differences among the four batches of TAMs and Glucantime®. The inhibitory concentrations (IC50) determined by the amastigote-infected macrophage model for TAM01/03 and Glucantime® were, respectively: 26.3µg/ml and 127.6µg/ml for L. chagasi, 15.4µg /ml and 22.9µg/ml for L. amazonensis, and 12.1µg/ml and 24.2µg/ml for L. (V.) braziliensis. The activities of the four batches of TAMs were confirmed in an in vivo model by assessing, during eight weeks skin lesions caused by L. braziliensis in hamster that were treated with 20mg Sb v/Kg/day for 30 consecutive days. The meglumine antimoniate produced by Farmanguinhos was as effective as the reference drug, Glucantime®-Aventis, against three species of Leishmania that are of medical importance in Brazil.

  4. In vitro and in vivo activity of meglumine antimoniate produced at Farmanguinhos-Fiocruz, Brazil, against Leishmania (Leishmania amazonensis, L (L. chagasi and L (Viannia braziliensis

    Directory of Open Access Journals (Sweden)

    Eliane de Morais-Teixeira

    2008-06-01

    Full Text Available The leishmanicidal activity of four batches of meglumine antimoniate, produced in Farmanguinhos-Fiocruz, Brazil (TAMs, was assessed and compared to Glucantime®-Aventis Pharma Ltda. Using the amastigote-like in vitro model, the active concentrations of Sb v varied from 10µg/ml to 300 µg/ml for L. (L. chagasi and from 50µg/ml to 300µg/ml for L. (L. amazonensis, with no statistically significant differences among the four batches of TAMs and Glucantime®. The inhibitory concentrations (IC50 determined by the amastigote-infected macrophage model for TAM01/03 and Glucantime® were, respectively: 26.3µg/ml and 127.6µg/ml for L. chagasi, 15.4µg /ml and 22.9µg/ml for L. amazonensis, and 12.1µg/ml and 24.2µg/ml for L. (V. braziliensis. The activities of the four batches of TAMs were confirmed in an in vivo model by assessing, during eight weeks skin lesions caused by L. braziliensis in hamster that were treated with 20mg Sb v/Kg/day for 30 consecutive days. The meglumine antimoniate produced by Farmanguinhos was as effective as the reference drug, Glucantime®-Aventis, against three species of Leishmania that are of medical importance in Brazil.

  5. Lutzomyia reducta Feliciangeli et al., 1988, a host of Leishmania amazonensis, sympatric with two other members of the Flaviscutellata complex in southern Amazonas and Rondônia, Brazil (Diptera: Psychodidae Lutzomyia reducta Feliciangeli et al., 1988 um hospedeiro de Leishmania amazonensis, simpátrico com duas outras espécies do complexo flaviscutellata no sul do Amazonas e Rondônica, Brasil (Diptera: Psychodidae

    Directory of Open Access Journals (Sweden)

    R. A. Freitas

    1989-09-01

    Full Text Available A member of the Lutzomyia flaviscutellata complex from Rondônia and southern Amazonas States, Brazil, is so close to the Venezuelan Lutzomyia olmeca recuta Feliciangeli et al., 1988, that it is regarded as belonging to the same species. Since this phlebotomine co-extis with L. olmeca nociva in Brazil, the subspecific status of the former is untenable and is rased to specific rank, as Lutzomyia reducta. The Brazilian material is described and illustrated, and compared with specimens of L. o. nociva and L. flaviscutellata from the same area. Keys to the known taxa of the flaviscutellata complex are presented. Leishmania amazonensis was isolated from one heavily infected specimen of L. reducta, making this the third species of the flaviscutellata complex to be implicated as a vector of this parasite in Brazil. The relative abundance of the three sympatric flaviscutellata complex species varies locally and appears to be related to soil drainage. L. reducta constituted about 25% if all phlebotomines captured in Disney traps at poorly drained and well drained site, but appears not to coloniza areas subject to periodic flooding. L. olmeca nociva was restricted to poorly drained areas not subject to flooding, whereas L. flaviscutellata was ubiquitous L. reducta has never been detected north of the Amazon river in Brazil, but absence of recosrds from western and northwestern Amazonas State may reflect lack of collecting in these areas.Um flebotomíneo do complexo Lutzomyia flaviscutellata, de Rondônia e sul do Amazonas, Brasil é tão parecido com Lutzomyia olmeca reducta, que é considerado como sendo da mesma espécie. Este flebotomíneo ocorre junto com L. olmeca nociva, portanto o nome é emendado para o nível de espécie, como Lutzomyia reducta. O material do Brasil é descrito e ilustrado, e comparado com exemplares de L. o. nociva e L. flaviscutellata da mesma área. Chaves para as espécies e subespécies do complexo flaviscutellata são incluídas. Leishmania amazonensis foi isolada em um exemplar de L. reducta altamente infectado, tornando esta espécie a terceira a ser implicada como vetor desta leishmania no Brasil. A abundância relativa das três espécies simpátricas do complexo flaviscutellata varia em escala local e aparenta ter relação com a drenagem do solo. L. reducta constituiu cerca de 25% dos flebotomíneos capturados em armadilhas Disney em locais mal e bem drenados, porém não foi encontrada em locais sujeitos a inundações. L. olmeca nociva era restrita às áreas mal drenadas não sujeitas a inundações, enquanto L. flaviscutellata foi capturada neste dois ambientes e também numa área periodicamente inundada. L. reducta não tem sido assinalada ao norte do Rio Amazonas no Brasil, porém a ausência de registros do oeste e noroeste do Estado do Amazonas possa refletri a falta de levantamento nestas áreas.

  6. Modulation of Leishmania (L.) amazonensis Growth in Cultured Mouse Macrophages by Prostaglandins and Platelet Activating Factor

    OpenAIRE

    Lonardoni, M. V. C.; Barbieri, C. L.; Russo, M.; Jancar, S.

    1994-01-01

    The role of endogenously synthesized PAF and prostaglandins on the infection of mouse macrophages by Letsbmanta (L.) amazonensis was investigated, as well as the possible correlation between the effects of these inflammatory mediators with nitric oxide production. It was found that pretreatment of macrophages with 10?5 M of the PAF antagonists, BN-52021 or WEB-2086, increased macrophage infection by 17 and 59%, respectively. The cyclooxygenase inhibitor, indomethacin (1...

  7. Isolation of an enriched plasma membrame subpellicular microtubule fraction of Leishmania mexicana amazonensis

    OpenAIRE

    Timm, Solange L.; Leon, Leonor L.; Pereira, Neize M.; Wanderley De Souza; Queiroz Cruz, M.; Bra?scher, Helena M.; Oliveira Lima, A.

    1980-01-01

    A cell fractionation procedure previously developed for Trypanosoma cruzi was applied to isolated the plasma membrane of promastigotes of Leishania mexicana amazonensis. The cell, swollen in an hypotonic mediun, were disrupted in the presence of a nonionic detergent and the membrane fraction isolated by differencial centrifugation. Electron microscopy showed that the fraction consisted of pieces of the plasma membrane associated with subpellicular microtubules. It was also shown that this fra...

  8. Molecular Modeling Approaches for Determining Gene Function: application to a Putative Poly-A Binding Protein from Leishmania amazonensis (LaPABP

    Directory of Open Access Journals (Sweden)

    Silva-Jr FP

    2002-01-01

    Full Text Available The great expansion in the number of genome sequencing projects has revealed the importance of computational methods to speed up the characterization of unknown genes. These studies have been improved by the use of three dimensional information from the predicted proteins generated by molecular modeling techniques. In this work, we disclose the structure-function relationship of a gene product from Leishmania amazonensis by applying molecular modeling and bioinformatics techniques. The analyzed sequence encodes a 159 aminoacids polypeptide (estimated 18 kDa and was denoted LaPABP for its high homology with poly-A binding proteins from trypanosomatids. The domain structure, clustering analysis and a three dimensional model of LaPABP, basically obtained by homology modeling on the structure of the human poly-A binding protein, are described. Based on the analysis of the electrostatic potential mapped on the model's surface and conservation of intramolecular contacts responsible for folding stabilization we hypothesize that this protein may have less avidity to RNA than it's L. major counterpart but still account for a significant functional activity in the parasite. The model obtained will help in the design of mutagenesis experiments aimed to elucidate the mechanism of gene expression in trypanosomatids and serve as a starting point for its exploration as a potential source of targets for a rational chemotherapy.

  9. Papel de la vacuola parasitófora de macrófagos de ratón infectados por Leishmania amazonensis en la adquisición de moléculas / Role of the parasitophorous vacuole of murine macrophages infected with Leishmania amazonensis in molecule acquisition

    Scientific Electronic Library Online (English)

    Tania M, Cortázar; Joselín, Hernández; María Clara, Echeverry; Marcela, Camacho.

    2006-10-01

    Full Text Available Introducción. Leishmania son parásitos intracelulares de macrófagos, confinados en compartimentos denominados vacuolas parasitóforas. La permeabilidad de este compartimento depende de su interacción con el tráfico vesicular y transportadores presentes en su membrana. Objetivo. En este trabajo se est [...] udió la permeabilidad de la membrana de la vacuola parasitófora en la línea celular J774.A1 infectada con Leishmania amazonensis, in situ y en compartimentos aislados. Materiales y métodos. El aislamiento de vacuolas parasitóforas se hizo por gradiente de densidad. La permeabilidad de la membrana de estas se valoró por distribución de sondas fluorescentes y electrofisiología. Para establecer indirectamente el transporte de protones se usó naranja de acridina. La presencia de transportadores ABC sensibles a probenecid se estableció con amarillo lucifer y calceína. Por primera vez con la técnica de patch-clamp se registraron corrientes en la membrana de este compartimento aislado. Resultados. La vacuola parasitófora colorea de rojo con naranja de acridina indicando un pH ácido. Concentra amarillo lucifer a través de un transportador sensible a probenecid, pero excluye la sonda calceína. Vacuolas aisladas se marcan de rojo con naranja de acridina y concentran amarillo lucifer a través de un transportador sensible a probenecid. Estas vacuolas excluyeron calceína y presentaron en su membrana una corriente iónica que se activa a diferencias de potencial cercanas a 60 mV, con una conductancia de 46 ± 3 pS. Conclusiones. Se pueden aislar vacuolas parasitóforas con propiedades de permeabilidad que preservan mecanismos de transporte similares a los encontrados in situ. Se registra por primera vez la presencia de una corriente iónica poco selectiva en la membrana de este compartimiento. Abstract in english Introduction. Leishmania are intracellular parasites of macrophages, confined into compartments known as parasitophorous vacuoles. The permeability of this compartment depends on its interaction with the endocytic pathway and transport proteins present on its membrane. Objective. The membrane permea [...] bility of the parasitophorous vacuole was studied in J774.A1- macrophage like cells infected with Leishmania amazonensis, in situ and on isolated compartments. Materials and methods. The parasitophorous vacuoles were isolated by density gradients. Fluorescent probe distribution and electrophysiological recordings were used to determine parasitophorous vacuole membrane permeability. Proton transport was evaluated indirectly by acridine orange staining. Probenecid sensitive ABC transporters were detected using the fluorescent probes lucifer yellow and calcein. For the first time ion currents were recorded on the membrane of isolated parasitophorous vacuoles using the patch clamp technique. Results. The parasitophorous vacuole stains red with acridine orange indicating an acidic compartment. It concentrates lucifer yellow by means of a probenecid sensitive transporter but excludes calcein. Isolated vacuoles stained red with acridine orange and concentrated lucifer yellow by means of a probenecid sensitive transporter. These vacuoles excluded calcein and showed an ion current in their membrane which is activated at potentials close to 60 mV with a mean conductance of 46 ± 3 pS. Conclusions. Isolated parasitophorous vacuoles with permeability properties preserving transport mechanisms similar to those found in situ can be purified. A poorly selective ion current on the parasitophorous vacuole membrane is reported for the first time.

  10. Identification and characterization of new Leishmania promastigote surface antigens, LaPSA-38S and LiPSA-50S, as major immunodominant excreted/secreted components of L. amazonensis and L. infantum.

    Science.gov (United States)

    Bras-Gonçalves, Rachel; Petitdidier, Elodie; Pagniez, Julie; Veyrier, Renaud; Cibrelus, Prisca; Cavaleyra, Mireille; Maquaire, Sarah; Moreaux, Jérôme; Lemesre, Jean-Loup

    2014-06-01

    We have previously demonstrated that sera from dogs vaccinated with excreted/secreted antigens (ESA) of Leishmania infantum promastigotes (LiESAp) mainly recognized an immunodominant antigen of 54 kDa. An anti-LiESAp-specific IgG2 humoral response was observed and associated to Th1-type response in vaccinated dogs. This response was highly correlated with a long-lasting and strong LiESAp-vaccine protection toward L. infantum experimental infection. In addition, it was also shown that dogs from the vaccinated group developed a selective IgG2 response against an immunodominant antigen of 45 kDa of Leishmania amazonensis ESA promastigotes (LaESAp). In order to identify and characterize these immunodominant antigens, a mouse monoclonal antibody (mAb F5) was produced by immunization against LaESAp. It was found to recognize the major antigenic targets of both LaESAp and LiESAp. Analysis with mAb F5 of L. amazonensis amastigote and promastigote cDNA expression libraries enabled the identification of clones encoding proteins with significant structural homology to the promastigote surface antigens named PSA-2/gp-46. Among them, one clone presented a full-length cDNA and encoded a novel L. amazonensis protein of 38.6 kDa calculated molecular mass (LaPSA-38S) sharing an amino acid sequence consistent with that of the PSA polymorphic family and a N-terminal signal peptide, characteristic of a secreted protein. We then screened a L. infantum promastigote DNA cosmid library using a cDNA probe derived from the LaPSA-38S gene and identified a full-length clone of a novel excreted/secreted protein of L. infantum with a calculated molecular mass of 49.2 kDa and named LiPSA-50S. The fact that a significant immunological reactivity was observed against PSA, suggests that these newly identified proteins could have an important immunoregulatory influence on the immune response. This hypothesis is supported by the fact that (i) these proteins were naturally excreted/secreted by viable Leishmania promastigotes and amastigotes, and (ii) they are selectively recognized by vaccinated and protected dogs. PMID:24614507

  11. Effect of Elatol, Isolated from Red Seaweed Laurencia dendroidea, on Leishmania amazonensis

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    Celso Vataru Nakamura

    2010-10-01

    Full Text Available In the present study, we investigated the antileishmanial activity of sesquiterpene elatol, the major constituent of the Brazilian red seaweed Laurencia dendroidea (Hudson J.V. Lamouroux, against L. amazonensis. Elatol after 72 h of treatment, showed an IC50 of 4.0 µM and 0.45 µM for promastigote and intracellular amastigote forms of L. amazonensis, respectively. By scanning and transmission electron microscopy, parasites treated with elatol revealed notable changes compared with control cells, including: pronounced swelling of the mitochondrion; appearance of concentric membrane structures inside the organelle; destabilization of the plasma membrane; and formation of membrane structures, apparently an extension of the endoplasmic reticulum, which is suggestive of an autophagic process. A cytotoxicity assay showed that the action of the isolated compound is more specific for protozoa, and it is not toxic to macrophages. Our studies indicated that elatol is a potent antiproliferative agent against promastigote and intracellular amastigote forms, and may have important advantages for the development of new anti-leishamanial chemotherapies.

  12. Synthesis, evaluation against Leishmania amazonensis and cytotoxicity assays in macrophages of sixteen new congeners Morita-Baylis-Hillman adducts.

    Science.gov (United States)

    Silva, Fábio P L; de Assis, Priscilla A C; Junior, Claudio G L; de Andrade, Natália G; da Cunha, Saraghina M D; Oliveira, Márcia R; Vasconcellos, Mário L A A

    2011-09-01

    We report the design, synthesis, in vitro evaluation against Leishmania amazonensis (IC(50)), cytotoxicity assays in macrophages (CC(50)), and selectivity index (SICC(50)/IC(50)) of sixteen new congeners aromatic Morita-Baylis-Hillman adducts 1-16. The 1-16 were prepared in good to excellent yields (58%-97%) from the "one pot" Morita-Baylis-Hillman Reaction between the aldehydes 29-36 and the acrylates 27 or 28 under DABCO as promoter. The MBHA 2-[Hydroxy(2-nitrophenyl)propyl] propanoate (1, IC(50) = 7.52 ?g/mL or 28.38 ?M; CC(50) = 35.77 ?g/mL or 134.98 ?M; SI = 4.75) and 2-[Hydroxy(2-nitrophenyl)hydroxyethyl] propanoate (9, IC(50) = 5.48 ?g/mL or 20.52 ?M; CC(50) = 29.81 ?g/mL or 111.64c ?M and, SI = 5.43) were the most effective and safe evaluated compounds. PMID:21775030

  13. Enhancement of Leishmania amazonensis infection in BCG non-responder mice by BCG-antigen specific vaccine

    Directory of Open Access Journals (Sweden)

    Kátia da Silva Calabrese

    1992-01-01

    Full Text Available Different patterns of cutaneous leishmaniasis can be induced when a challenge of alike dose of Leishmania amazonensis amastigotes in various inbred strains was applied. Two strains of mice, the Balb/c and C57 BL/10J, showed exceptional suscepbility, and 10(elevado a sexta potência amastigotes infective dose lead, to ulcerative progressive lesions with cutaneous metastasis and loss by necrosis of leg on wich the footpad primary lesion occured. Lesions were also progressive but in a lower degree when C3H/HeN and C57BL/6 were infected. Lesions progress slowly in DBA/2 mice presenting lesions wich reach a discreet peack after 12 weeks, do not heal but do not uncerate. DBA/2 mice is, therefore, a good model for immunomodualtion. In attempt to determine the influence of BCG in vaccination schedule using microsomal fraction, DBA/2 became an excellent model, since it is also a non-responder to BCG. Vaccination of DBA/2 mice, receiving the same 10(elevado a sexta potência BCG viable dose and 10 *g or 50 *g of protein content of microsomal fraction, lead to a progressive disease with time course similar to those observed in susceptible non-vaccinated C57BL/10J mice after 6 months of observation. An enhancement of infection in BCG non-responder mice suggests that use of BCG as immunostimulant in humans could be critical for both vaccination and immunoprophylactic strategies.

  14. In vitro initial immune response against Leishmania amazonensis infection is characterized by an increased production of IL-10 and IL-13

    Scientific Electronic Library Online (English)

    Zirlane Castelo B, Coêlho; Maria Jania, Teixeira; Erika Freitas, Mota; Mércia Sindeaux, Frutuoso; João Santana da, Silva; Aldina, Barral; Manoel, Barral-Netto; Margarida Maria L, Pompeu.

    2010-10-01

    Full Text Available The initial encounter of Leishmania with its host's immune system is important in the outcome of infection. Previous studies have shown that PBMCs from healthy volunteers (HV) exposed to Leishmania differ in IFN-? production. We have expanded such observations evaluating the profile and kinetics of [...] cytokines (IFN-?, IL-12p70, IL-10, IL-13), chemokines (CCL5, CCL3, CCL4, CXCL10), and chemokine receptors (CCR1,CCR5, CXCR3, CCR4) in vitro L. amazonensis-stimulated of HV's PBMCs. HVs were divided in groups of high (HR) or low (LR) IFN-? responders. In both groups, HR and LR, after L. amazonensis infection there was a predominance of IL-10 and IL-13 over IFN-? production, while IL-12 was produced in similar amount. Regarding chemokines, a more striking difference was observed for CCL3 expression that was lower at 12 hours and 48 hours post infection in LR than in HR. Interestingly, a downregulation of CCR5 and a greater expression of CCR4 were found in low IFN-? responders. These data suggest that early after L. amazonensis infection there is a cytokine milieu dominated by IL-13 and IL-10, and despite of this environment, IFN-? is produced, supporting the complexity of the response. It is noteworthy that the pattern of immune response is mounted in first hours after Leishmania stimulation, with the definition of the differentiation of Th1 versus Th2 cells. It remains to be determined if such an in vitro difference has an in vivo counterpart in terms of susceptibility to infection

  15. Dolabelladienetriol, a Compound from Dictyota pfaffii Algae, Inhibits the Infection by Leishmania amazonensis

    OpenAIRE

    Soares, Deivid Costa; Calegari-silva, Teresa C.; Lopes, Ulisses G.; Teixeira, Vale?ria L.; Palmer Paixa?o, Izabel C. N.; Cirne-santos, Claudio; Bou-habib, Dumith Chequer; Saraiva, Elvira M.

    2012-01-01

    Leishmaniasis is a global disease, which is treated with expensive compounds. Anti-leishmaniasis therapy causes severe side effects, and parasite resistance is often observed, which highlights the importance of discovering new drugs against its causal agent, the protozoan parasite Leishmania. Recently, the geographical overlapping distribution of leishmaniasis and the infection by the human immunodeficiency virus type 1 (HIV-1) has contributed to a dramatic increase in the number of individua...

  16. Lutzomyia reducta Feliciangeli et al., 1988, a host of Leishmania amazonensis, sympatric with two other members of the Flaviscutellata complex in southern Amazonas and Rondônia, Brazil (Diptera: Psychodidae) / Lutzomyia reducta Feliciangeli et al., 1988 um hospedeiro de Leishmania amazonensis, simpátrico com duas outras espécies do complexo flaviscutellata no sul do Amazonas e Rondônica, Brasil (Diptera: Psychodidae)

    Scientific Electronic Library Online (English)

    R. A., Freitas; T. V., Barrett; R. D., Naiff.

    1989-09-01

    Full Text Available Um flebotomíneo do complexo Lutzomyia flaviscutellata, de Rondônia e sul do Amazonas, Brasil é tão parecido com Lutzomyia olmeca reducta, que é considerado como sendo da mesma espécie. Este flebotomíneo ocorre junto com L. olmeca nociva, portanto o nome é emendado para o nível de espécie, como Lutzo [...] myia reducta. O material do Brasil é descrito e ilustrado, e comparado com exemplares de L. o. nociva e L. flaviscutellata da mesma área. Chaves para as espécies e subespécies do complexo flaviscutellata são incluídas. Leishmania amazonensis foi isolada em um exemplar de L. reducta altamente infectado, tornando esta espécie a terceira a ser implicada como vetor desta leishmania no Brasil. A abundância relativa das três espécies simpátricas do complexo flaviscutellata varia em escala local e aparenta ter relação com a drenagem do solo. L. reducta constituiu cerca de 25% dos flebotomíneos capturados em armadilhas Disney em locais mal e bem drenados, porém não foi encontrada em locais sujeitos a inundações. L. olmeca nociva era restrita às áreas mal drenadas não sujeitas a inundações, enquanto L. flaviscutellata foi capturada neste dois ambientes e também numa área periodicamente inundada. L. reducta não tem sido assinalada ao norte do Rio Amazonas no Brasil, porém a ausência de registros do oeste e noroeste do Estado do Amazonas possa refletri a falta de levantamento nestas áreas. Abstract in english A member of the Lutzomyia flaviscutellata complex from Rondônia and southern Amazonas States, Brazil, is so close to the Venezuelan Lutzomyia olmeca recuta Feliciangeli et al., 1988, that it is regarded as belonging to the same species. Since this phlebotomine co-extis with L. olmeca nociva in Brazi [...] l, the subspecific status of the former is untenable and is rased to specific rank, as Lutzomyia reducta. The Brazilian material is described and illustrated, and compared with specimens of L. o. nociva and L. flaviscutellata from the same area. Keys to the known taxa of the flaviscutellata complex are presented. Leishmania amazonensis was isolated from one heavily infected specimen of L. reducta, making this the third species of the flaviscutellata complex to be implicated as a vector of this parasite in Brazil. The relative abundance of the three sympatric flaviscutellata complex species varies locally and appears to be related to soil drainage. L. reducta constituted about 25% if all phlebotomines captured in Disney traps at poorly drained and well drained site, but appears not to coloniza areas subject to periodic flooding. L. olmeca nociva was restricted to poorly drained areas not subject to flooding, whereas L. flaviscutellata was ubiquitous L. reducta has never been detected north of the Amazon river in Brazil, but absence of recosrds from western and northwestern Amazonas State may reflect lack of collecting in these areas.

  17. Study of ionizing radiation as a tool for select promastigotes forms of Leishmania Amazonensis, and the megalomaniac response in experimental models

    International Nuclear Information System (INIS)

    Actually, millions of people around the globe are under the risk of infection by a protozoan transmitted by a bit of a sand fly. This parasite is a Leishmania spp. This causes a wide spectrum disease, since a cutaneous disease to a visceral one. The cutaneous form is the major clinical manifestation (above 90%). The ionizing radiation, produced in a 60Co font, had being successes used to promote physical-chemical transformations on different protozoan, including Leishmania spp. In previous work was determined that promastigotes forms of Leishmania amazonensis, irradiated with different doses of radiation, lost their viability maintaining, however, their immunogenicity. In this work, was studied the use of ionizing radiation as a tool for selection of meta cyclic forms of the parasite in axenic culture, for a possible efficient irradiated immuno gene production. Our results shown that cultures irradiated with 400 Gy of gamma irradiation, has 75% of metacyclic form, which are capable to produce, in vitro, an infection that is similar the natural occurrence. These irradiated parasites have their internal cellular structure modified, maintaining their external structure intact. Susceptible strain of mice immunized with leishmania irradiated with different doses had high immunoglobulin production, and maintained this production after the challenge with naive parasites. In other strains this default was similar, however in lower titles. Immunodeficient mice didn't produce immunoglobulin nor on the immunization or on the challenge. (author)

  18. Sobre a sensibilidade da cultura de leucócitos circulantes na detecção de Leishmania no sangue periférico de pacientes com leishmaniose tegumentar

    Directory of Open Access Journals (Sweden)

    Fernando T. Silveira

    1989-09-01

    Full Text Available Foi investigada a presença de Leishmania, através da cultura de leucócitos circulantes, no sangue periférico de 60 pacientes portadores de leishmaniose tegumentar americana, nas suas diferentes formas clínicas, assim como nas principais fases evolutivas da doença. Biópsias de lesões cutâneas e/ou de mucosa desses pacientes foram obtidas com a finalidade de isolar e caracterizar os parasitas, através da técnica de anticorpos monoclonais. Dos 60 pacientes examinados, foram isoladas 40 amostras de Leishmania das lesões biopsiadas, sendo 5 de Leishmania (V. brasiliensis, 3 de L. (V. guyanensis, 1 de L. (V. lainsoni, 13 de L. (L. amazonensis e 18 não puderam ser caracterizados a nível específico, porém, reagiram com anticorpos monoclonais do grupo braziliensis. Quanto àpesquisa através das culturas de leucócitos circulantes, esta revelou resultados completamente negativos. Com base nesses achados, os autores concluíram ser pouco consistente atribuir valor à cultura de leucócitos para o diagnóstico da leishmaniose tegumentar.The possible presence of Leishmania in the peripheral blood of 60 patients with American cutaneous leishmaniasis was investigated by the culture of circulating leucocytes. Patients were selected with a variety ofclinical forms ofthe disease and in different evolutionary stages of infection. Biopsies of skin and/or mucosal lesions were made in order to isolate the parasites, which were identified using monoclonal antibodies. 40 isolations were obtained, including 5 of Leishmania (Viannia braziliensis, 3 L. (V. guyanensis, 1 L. (V. lainsoni, 13 L. (Leishmania amazonensis and 18 which could only be identified as parasites of the braziliensis complex. Cultures of circulanting leucocytes were consistently negative, and the authors conclude that this method is of little use in diagnosis of cutaneous or mucocutaneous leishmaniasis.

  19. Sobre a sensibilidade da cultura de leucócitos circulantes na detecção de Leishmania no sangue periférico de pacientes com leishmaniose tegumentar

    Scientific Electronic Library Online (English)

    Fernando T., Silveira; Ralph, Lainson; Jeffrey J., Shaw; Edna A., Ishikawa; Adelson A.A., Souza; Roseli R., Braga.

    1989-09-01

    Full Text Available Foi investigada a presença de Leishmania, através da cultura de leucócitos circulantes, no sangue periférico de 60 pacientes portadores de leishmaniose tegumentar americana, nas suas diferentes formas clínicas, assim como nas principais fases evolutivas da doença. Biópsias de lesões cutâneas e/ou de [...] mucosa desses pacientes foram obtidas com a finalidade de isolar e caracterizar os parasitas, através da técnica de anticorpos monoclonais. Dos 60 pacientes examinados, foram isoladas 40 amostras de Leishmania das lesões biopsiadas, sendo 5 de Leishmania (V.) brasiliensis, 3 de L. (V.) guyanensis, 1 de L. (V.) lainsoni, 13 de L. (L.) amazonensis e 18 não puderam ser caracterizados a nível específico, porém, reagiram com anticorpos monoclonais do grupo braziliensis. Quanto àpesquisa através das culturas de leucócitos circulantes, esta revelou resultados completamente negativos. Com base nesses achados, os autores concluíram ser pouco consistente atribuir valor à cultura de leucócitos para o diagnóstico da leishmaniose tegumentar. Abstract in english The possible presence of Leishmania in the peripheral blood of 60 patients with American cutaneous leishmaniasis was investigated by the culture of circulating leucocytes. Patients were selected with a variety ofclinical forms ofthe disease and in different evolutionary stages of infection. Biopsies [...] of skin and/or mucosal lesions were made in order to isolate the parasites, which were identified using monoclonal antibodies. 40 isolations were obtained, including 5 of Leishmania (Viannia) braziliensis, 3 L. (V.) guyanensis, 1 L. (V.) lainsoni, 13 L. (Leishmania) amazonensis and 18 which could only be identified as parasites of the braziliensis complex. Cultures of circulanting leucocytes were consistently negative, and the authors conclude that this method is of little use in diagnosis of cutaneous or mucocutaneous leishmaniasis.

  20. Identification and purification of immunogenic proteins from nonliving promastigote polyvalent Leishmania vaccine (Leishvacin®) / Identificação e purificação de proteínas imunogênicas da vacina polivalente de promastigotas mortas de Leishmania (Leishvacin®)

    Scientific Electronic Library Online (English)

    Sandra Regina Afonso, Cardoso; João Carlos França da, Silva; Roberto Teodoro da, Costa; Wilson, Mayrink; Maria Norma, Melo; Marilene Suzan Marques, Michalick; Ibrahim Afrânio Willi, Liu; Ricardo Toshio, Fujiwara; Evaldo, Nascimento.

    2003-04-01

    Full Text Available Proteínas imunogênicas da vacina polivalente de promastigotas mortas de leishmanias (Leishvacin®) produzida pela Biobrás Bioquímica do Brasil, Montes Claros, Minas Gerais, Brasil foram identificadas e purificadas por eletroforese em gel de poliacrilamida e eletroeluição. Camundongos C57BL/10 foram v [...] acinados com proteínas de pesos moleculares estimados em 42, 46, 63, 66, 73, 87, 97 e 160kDa em três doses de 30µg de cada proteína combinada com 250µg de Corynebacteriumparvum em intervalos de 15 dias e desafiados com uma infecção desafio de 10(5) promastigotas infectantes de Leishmania (Leishmania) amazonensis na base da cauda. Foram avaliadas a habilidade dessas proteínas em induzir resposta imune e proteção dos animais vacinados após a infecção desafio. Nenhuma diferença estatística foi observada nos níveis de IFN-g nos grupos vacinados em comparação ao grupo controle. Proteção de 28,57; 42,86; 57,14; 42,86; 42,86, 57,14; 42,86; 57,14% foi demonstrado para cada proteína. Abstract in english Immunogenic proteins from nonliving promastigote polyvalent Leishmania vaccine against American tegumentary leishmaniasis (Leishvacin®), produced by Biobrás (Biochemistry of Brazil ), Montes Claros, State of Minas Gerais, Brazil, were identified and purified by polyacrylamide electrophoresis gel and [...] electroelution. C57BL/10 mice were vaccinated with proteins with estimated molecular weights of 42, 46, 63, 66, 73, 87, 97, and 160kDa in three doses of 30µg of each protein at 15-day intervals combined with 250µg of Corynebacterium parvum followed by a challenge infection with 10(5) infective promastigotes from Leishmania (Leishmania) amazonensis. The ability of these proteins to induce immune response and protection was analyzed. No statistical difference was observed in the level of IFN-g induced by proteins in vaccinated groups in comparison with control groups. Six months after challenge infection, protection levels of 28.57; 42.86; 57.14; 42.86; 42.86, 57.14; 42.86 and 57.14% were demonstrated for each purified protein.

  1. Intergenic sequences from the heat-shock protein 83-encoding gene cluster in Leishmania mexicana amazonensis promote and regulate reporter gene expression in transfected parasites.

    Science.gov (United States)

    Aly, R; Argaman, M; Pinelli, E; Shapira, M

    1993-05-30

    Regulation of expression from hsp83 gene cluster encoding heat-shock protein (HSP) 83 of the protozoan parasite Leishmania mexicana amazonensis (L.m.a) was examined. The first gene from this cluster, along with 8 kb of flanking sequences, was cloned, and intergenic region (IR) sequences were found upstream from the cluster. L.m.a. parasites were electroporated with a plasmid (pICI) in which the chloramphenicol acetyltransferase (CAT)-encoding gene (cat) was cloned between two IRs derived from an internal repeat unit of the hsp83 cluster, resulting in CAT activity at 26 degrees C. Exposure of cells transfected with this plasmid to a 35 degrees C heat shock led to an increase in CAT activity, within a range similar to that observed for the accumulation of hsp83 steady-state mRNA at 35 degrees C. S1 analysis of the hsp83 mRNA showed that the major part of the IR was transcribed and mostly present as 3' non-translated extensions. Deletion analysis of the flanking regions indicated that the presence of IR sequences, both upstream and downstream from cat, was critical to its expression. Partial deletions that removed the original AG splice acceptor site (leaving 289 bp upstream) and downstream IR sequences (leaving 200 bp) did not eliminate CAT activity. However, this combined deletion altered the effect of temperature on cat expression in transfected cells, as compared with the activity measured in cells transfected with the original plasmid. PMID:8500758

  2. Regulation of Leishmania (L.) amazonensis Protein Expression by Host T Cell Dependent Responses: Differential Expression of Oligopeptidase B, Tryparedoxin Peroxidase and HSP70 Isoforms in Amastigotes Isolated from BALB/c and BALB/c Nude Mice

    Science.gov (United States)

    Teixeira, Priscila Camillo; Velasquez, Leonardo Garcia; Lepique, Ana Paula; de Rezende, Eloiza; Bonatto, José Matheus Camargo; Barcinski, Marcello Andre; Cunha-Neto, Edecio; Stolf, Beatriz Simonsen

    2015-01-01

    Leishmaniasis is an important disease that affects 12 million people in 88 countries, with 2 million new cases every year. Leishmania amazonensis is an important agent in Brazil, leading to clinical forms varying from localized (LCL) to diffuse cutaneous leishmaniasis (DCL). One interesting issue rarely analyzed is how host immune response affects Leishmania phenotype and virulence. Aiming to study the effect of host immune system on Leishmania proteins we compared proteomes of amastigotes isolated from BALB/c and BALB/c nude mice. The athymic nude mice may resemble patients with diffuse cutaneous leishmaniasis, considered T-cell hyposensitive or anergic to Leishmania´s antigens. This work is the first to compare modifications in amastigotes’ proteomes driven by host immune response. Among the 44 differentially expressed spots, there were proteins related to oxidative/nitrosative stress and proteases. Some correspond to known Leishmania virulence factors such as OPB and tryparedoxin peroxidase. Specific isoforms of these two proteins were increased in parasites from nude mice, suggesting that T cells probably restrain their posttranslational modifications in BALB/c mice. On the other hand, an isoform of HSP70 was increased in amastigotes from BALB/c mice. We believe our study may allow identification of potential virulence factors and ways of regulating their expression. PMID:25692783

  3. El rol de tres pruebas de ELISA con antígenos de promastigotes de Leishmania braziliensis, L. amazonensis y L. guyanensis en el diagnóstico de leishmaniasis tegumentaria Role of three ELISA tests using promastigote homogenates of Leishmania braziliensis, L. amazonensis and L. guyanensis in the diagnosis of tegumentary leishmaniasis

    Directory of Open Access Journals (Sweden)

    José F. Gil

    2011-10-01

    Full Text Available Es importante conocer si la variabilidad de especies de Leishmania circulantes en una región afecta la performance de las pruebas de ELISA estandarizadas para el diagnostico de la leishmaniasis. El objetivo de este trabajo fue analizar la reactividad de la prueba de ELISA utilizando homogenados de promastigotes de Leishmania (V. braziliensis (ELISAb, L (L amazonensis (ELISAa y L (V. guyanensis (ELISAg frente a distintos grupos de sueros. Se estudiaron muestras de personas con leishmaniasis cutánea (n = 37, leishmaniasis mucocutánea (n = 8, no infectados (n = 52, infectadas por Trypanosoma cruzi (n = 11 e infecciones mixtas (n = 14. Se calcularon las sensibilidades, especificidades, cut off, valores predictivos, y se compararon las tres pruebas usando ANOVA, índice de concordancia kappa, comparación de curvas ROC e intervalos de confianza construidos por el método de bootstrap. Se encontraron diferencias significativas al comparar los niveles de DO de los sueros de pacientes con leishmaniasis cutánea respecto a los controles negativos, pero no se encontraron diferencias entre pruebas. Las sensibilidades calculadas fueron de 84.6% para ELISAb y ELISAa y de 88.5 para ELISAg, mientras que el valor de especificidad para las tres pruebas fue de 96.2. El índice de concordancia kappa y la comparación de curvas ROC mostraron performances similares para las tres pruebas (p = 0.225. La elevada reactividad obtenida para estas ELISAs frente a sueros de pacientes con leishmaniasis mucocutánea indica un importante potencial de esta técnica como complemento en el diagnóstico de la enfermedad.It is important to know whether the variability of species of Leishmania parasites circulating in a region affects the performance of the ELISA test for the diagnosis of leishmaniasis. Therefore, the aim of this study was to analyze the reactivity of the ELISA using homogenates of promastigotes of Leishmania (V. braziliensis (ELISAb, Leishmania (L amazonensis (ELISAa and Leishmania (V. guyanensis (ELISAg against different sera groups. Samples from individuals with cutaneous leishmaniasis (n = 37, mucocutaneous leishmaniasis (n = 8, healthy controls (n = 52, persons infected with Trypanosoma cruzi (n = 11 and mixed infections (n = 14 were included in the study. We calculated sensitivities, specificities, cut offs, and predictive values for the three tests and compared them using ANOVA, kappa index, ROC curves comparison, and confidence intervals calculated by the bootstrap method. Significant differences were found when comparing the OD levels of sera from patients with cutaneous leishmaniasis against healthy controls, but there were no differences when comparing the different ELISAs. The sensitivities calculated for ELISAb and ELISAa were 84.6 and of 88.5% for ELISAg, while the value of specificity for the three tests was 96.2. The kappa index (0.87 and comparison of ROC curves showed similar performance for the three ELISAs (p = 0.225. The high reactivity obtained for these ELISAs in sera of patients with mucocutaneous leishmaniasis indicates this test as an important complement in the diagnosis of the disease.

  4. El rol de tres pruebas de ELISA con antígenos de promastigotes de Leishmania braziliensis, L. amazonensis y L. guyanensis en el diagnóstico de leishmaniasis tegumentaria / Role of three ELISA tests using promastigote homogenates of Leishmania braziliensis, L. amazonensis and L. guyanensis in the diagnosis of tegumentary leishmaniasis

    Scientific Electronic Library Online (English)

    José F., Gil; Carlos L., Hoyos; Rubén O., Cimino; Alejandro J., Krolewiecki; Inés, Lopéz Quiroga; Silvana P., Cajal; Marisa, Juárez; María F., García Bustos; María C., Mora; Jorge D., Marco; Julio R., Nasser.

    2011-10-01

    Full Text Available Es importante conocer si la variabilidad de especies de Leishmania circulantes en una región afecta la performance de las pruebas de ELISA estandarizadas para el diagnostico de la leishmaniasis. El objetivo de este trabajo fue analizar la reactividad de la prueba de ELISA utilizando homogenados de p [...] romastigotes de Leishmania (V.) braziliensis (ELISAb), L (L) amazonensis (ELISAa) y L (V.) guyanensis (ELISAg) frente a distintos grupos de sueros. Se estudiaron muestras de personas con leishmaniasis cutánea (n = 37), leishmaniasis mucocutánea (n = 8), no infectados (n = 52), infectadas por Trypanosoma cruzi (n = 11) e infecciones mixtas (n = 14). Se calcularon las sensibilidades, especificidades, cut off, valores predictivos, y se compararon las tres pruebas usando ANOVA, índice de concordancia kappa, comparación de curvas ROC e intervalos de confianza construidos por el método de bootstrap. Se encontraron diferencias significativas al comparar los niveles de DO de los sueros de pacientes con leishmaniasis cutánea respecto a los controles negativos, pero no se encontraron diferencias entre pruebas. Las sensibilidades calculadas fueron de 84.6% para ELISAb y ELISAa y de 88.5 para ELISAg, mientras que el valor de especificidad para las tres pruebas fue de 96.2. El índice de concordancia kappa y la comparación de curvas ROC mostraron performances similares para las tres pruebas (p = 0.225). La elevada reactividad obtenida para estas ELISAs frente a sueros de pacientes con leishmaniasis mucocutánea indica un importante potencial de esta técnica como complemento en el diagnóstico de la enfermedad. Abstract in english It is important to know whether the variability of species of Leishmania parasites circulating in a region affects the performance of the ELISA test for the diagnosis of leishmaniasis. Therefore, the aim of this study was to analyze the reactivity of the ELISA using homogenates of promastigotes of L [...] eishmania (V.) braziliensis (ELISAb), Leishmania (L) amazonensis (ELISAa) and Leishmania (V.) guyanensis (ELISAg) against different sera groups. Samples from individuals with cutaneous leishmaniasis (n = 37), mucocutaneous leishmaniasis (n = 8), healthy controls (n = 52), persons infected with Trypanosoma cruzi (n = 11) and mixed infections (n = 14) were included in the study. We calculated sensitivities, specificities, cut offs, and predictive values for the three tests and compared them using ANOVA, kappa index, ROC curves comparison, and confidence intervals calculated by the bootstrap method. Significant differences were found when comparing the OD levels of sera from patients with cutaneous leishmaniasis against healthy controls, but there were no differences when comparing the different ELISAs. The sensitivities calculated for ELISAb and ELISAa were 84.6 and of 88.5% for ELISAg, while the value of specificity for the three tests was 96.2. The kappa index (0.87) and comparison of ROC curves showed similar performance for the three ELISAs (p = 0.225). The high reactivity obtained for these ELISAs in sera of patients with mucocutaneous leishmaniasis indicates this test as an important complement in the diagnosis of the disease.

  5. Determinación de la producción de Öxido Nítrico en Macrófagos Activados J774.1 como respuesta al tamaño de la carga fagocítica de partículas de látex y Leishmania amazonensis Determination of Nitric Oxide Production in Activate Macrophages J774.1 as effect of Phagocitic Load Volume of Latex Beads and Leishmania amazonensis

    Directory of Open Access Journals (Sweden)

    Camargo Jiménez Maria Helena

    2000-06-01

    Full Text Available La leishmaniosis es una enfermedad parasitaria causada por el protozoario Leishmania. Cercade 12 millones de personas padecen esta enfermedad y 350 millones de personas están enriesgo de contraerla. Existe evidencia de que la infección por Leishmania amazonensisdisminuyela producción de óxido nítrico (NO de macrófagos; se ha interpretado que este deterioroes inducido por el parásito. Esta investigación corrobora esta idea, pero contradice que seaexclusivo de la infección. En este trabajo, cultivos celulares de macrófagos fueron expuestosa partículas de látex en diferentes proporciones buscando cargas fagocíticas y volúmenes defagosoma semejantes a los de la infección. Las concentraciones de nitrito y parámetros mor-fológicos se midieron a las 48 horas post fagocitosis e infección con 24 horas de activaciónmediante IFN-?y LPS. Se determinó que volúmenes similares de fagosomas generados porpartículas de látex o amastigotes de L. amazonensis, deterioran en la misma proporción laproducción de NO. Esto sugiere que este deterioro no depende de la naturaleza de la partículafagocitada. El incremento en el volumen de fagosoma se correlaciona con la disminución en laproducción de nitrito, por tanto, la expansión del fagosoma puede ser uno de los mecanismosimplicados en la disminución de la producción de NO. Los resultados apoyan la evidencia deque Leishmaniadisminuye la producción de NO pero contradicen la interpretación,comúnmente aceptada, de que este fenómeno es específico de la infección.Leishmaniasis is a parasitic disease caused by a protozoa of the genera Leishmania. Around 12million people are infected and 350 millions of people are risk to contract it. There is evidencethat infection by Leishmania amazonensisdecreases nitric oxide production; it has beeninterpreted that this impairment is induced by the parasite. This study confirmed this idea, butcontradicts that this impairment is exclusive of infection. In this work, cultured macrophageswere exposed to latex beads at diferents proportions, to simulate phagocitic loads andphagosome volumes resembling those of the infection. Nitrite concentration and morphologicalparameters were measured at 48 hours post phagocytosis and infection with 24 hours ofactivation induced by IFN-?and LPS. Our results determined that macrophages with similarvolume of phagosomes generated by latex beads or L. amazonensisamastigotes have the samedecrease in inducible NO production. This suggest that this partial inhibition does not depenton the nature of phagocited particle. Phagosome volume increase correlates with the decreasein inducible NO production. Therefore, phagosome expansion may be one of the mechanismimplicated in the disminution of inducible NO production. The results support the evidencethat Leishmaniareduces inducible NO production, but contradicts the common interpretationthat this fenomena is specific of infection.

  6. Assessment of PCR in the detection of Leishmania spp in experimentally infected individual phlebotomine sandflies (Diptera: Psychodidae: Phlebotominae Avaliação do PCR na investigação de Leishmania spp em flebotomíneos experimentalmente infectados (Diptera: Psychodidae: Phlebotominae

    Directory of Open Access Journals (Sweden)

    Érika M. MICHALSKY

    2002-10-01

    Full Text Available DNA amplification by the polymerase chain reaction (PCR was applied in the investigation of the presence of Leishmania (Kinetoplastida: Trypanosomatidae parasites in single phlebotomine sandflies. Three phlebotomine/parasite pairs were used: Lutzomyia longipalpis/Leishmania chagasi, Lutzomyia migonei/Leishmania amazonensis and Lutzomyia migonei/Leishmania braziliensis, all of them incriminated in the transmission of visceral or cutaneous leishmaniasis. DNA extraction was performed with whole insects, with no need of previous digestive tract dissection or pooling specimens. The presence of either mouse blood in the digestive tract of the sandflies or the digestive tract itself did not interfere in the PCR. Infection by as few as 10 Leishmania sp. per individual were sufficient for DNA amplification with genus-specific primers. Using primers for L. braziliensis and L. mexicana complexes, respectively, it was possible to discriminate between L. braziliensis and L. amazonensis in experimentally infected vectors (L. migonei.Neste trabalho avaliamos o uso da reação em cadeia da polimerase (PCR na investigação da presença de parasitas Leishmania (Kinetoplastida:Trypanosomatidae em flebotomíneos individuais. Para isso, foram utilizados três pares flebotomíneo/parasita: Lutzomyia longipalpis/Leishmania chagasi, Lutzomyia migonei/Leishmania amazonensis e Lutzomyia migonei/Leishmania braziliensis, todos eles incriminados na transmissão de leishmaniose cutânea ou visceral. O DNA total a ser amplificado foi extraído de flebotomíneos inteiros, contendo ou não o parasita, sem dissecção prévia do trato digestivo ou combinação de indivíduos. Conteúdos do trato digestivo de flebotomíneos, em especial sangue de camundongo, não interferiram na reação de amplificação. Dez parasitas Leishmania sp. por flebotomíneo foram suficientes para detecção com iniciadores gênero-específicos. Com a utilização de iniciadores para os complexos L. braziliensis e L. mexicana, respectivamente, foi possível discriminar entre L. braziliensis e L. amazonensis, em flebotomíneos infectados experimentalmente (L. migonei.

  7. Acercamiento al estudio de la interacción y salida de Leishmania amazonensis en un modelo in vitro con macrófagos murinos de la línea celular J774a.1

    Directory of Open Access Journals (Sweden)

    León Cabrera Sonia Andrea

    2006-06-01

    Full Text Available Los miembros del género Leishmania son parásitos intracelulares obligados, responsables de numerosas enfermedades humanas. Cumplen una parte muy importante de su ciclo de vida dentro del mamífero hospedero, en donde después de la fagocitosis por los macrófagos, los parásitos son confinados dentro de un compartimiento endolisosomal denominado vacuola parasitófora (VP, en el cual se replican siendo finalmente liberados infectando otros macrófagos y de esta forma ampliando la infección. Poco es el conocimiento que se tiene acerca de cómo ocurre el proceso de liberación de amastigotes de Leishmania que infectan macrófagos. Se sospecha que este mecanismo puede estar ocurriendo por un proceso de fusión de membranas. Mediciones de capacitancia
    de la membrana del macrófago y el uso de inhibidores de fusión de membranas soportan esta idea. El objetivo de este trabajo fue realizar seguimientos del ciclo infectivo de Leishmania amazonensis, para confirmar los hallazgos
    previos en cuanto a los tiempos en que probablemente puede estar ocurriendo la salida del amastigote. Además, se buscó determinar la viabilidad del parásito a lo largo del ciclo infectivo con el fin de comprender mejor la interacción hospedero-patógeno en el modelo in vitro; para ello se midió: viabilidad del parásito con tinción de diacetato de fluoresceína (DAF y ioduro de propidio (IP, porcentaje de infección y número de parásitos por célula (p/c. Los resultados sugieren que la salida de los parásitos puede presentarse entre las 72 y 78 horas post infección (hpi y entre las 96 y 120 hpi. Con los resultados de trabajos previos, y los datos presentados en este estudio, se ha propuesto que L. amazonensis puede presentar dos ciclos infectivos que se desarrollan durante cinco días en nuestras condiciones de cultivo in vitro. En las primeras 36-48 hpi el parásito se diferencia a amastigote. Después de su diferenciación comienza su división celular. Luego de las 72 hpi ocurre una disminución en el número de parásitos por célula (p/c que ha sido relacionada con el momento en el cual podría salir el parásito de su célula hospedera. La recuperación del número de p/c a las 96 hpi y la disminución presentada a las 120 hpi sugieren la ocurrencia de un nuevo ciclo infectivo. La viabilidad del amastigote se vio afectada a medida que transcurrió la infección. Durante las primeras 24 hpi prácticamente todos los parásitos fueron viables (93,85%
    y se observaron de color verde intenso dentro de las VP por marcaje con la sonda DAF. Entre el tercer y cuarto
    día se presentó una disminución significativa en la viabilidad de los parásitos p = 0,017 y p = 0,0097 respectivamente.
    Entre el tercer y quinto día post infección el cultivo en general se observó más deteriorado y se encontró
    una cantidad considerable de macrófagos no viables, pero aún con parásitos viables en el interior de la VP. Estas
    observaciones se han interpretado como competencia en el cultivo, lo que generaría déficit alimenticio,
    explicando la drástica disminución en la viabilidad general del cultivo. El descenso diario de un grupo de células infectadas podría ser la causa de la disminución en los porcentajes de infección. En este trabajo se desarrolló un método eficiente para marcar la membrana de macrófagos infectados con los análogos fluorescentes de fosfolípidos NBD-PE y RHO-PE con el fin de implementar la técnica FRET, y así evidenciar la fusión de una membrana no marcada como la de la VP, con una membrana previamente marcada como la del macrófago. Se estipuló que la concentración de 5 ?g/mL y 10 ?g/mL para las pruebas RHO-PE y NBD-PE respectivamente, puestas en contacto con macrófagos infectados en nuestras condiciones, fueron capaces de marcar clara y continuamente la membrana celular del 95,9% y 97,0% de los macrófagos. Asi mismo, con la menor formación de vesículas de la sonda comparada con otras concentraciones y con una

  8. Combining diagnostic procedures for the management of leishmaniasis in areas with high prevalence of Leishmania guyanensis / Procedimentos diagnósticos combinados no manejo da leishmaniose em áreas com alta prevalência de Leishmania guyanensis

    Scientific Electronic Library Online (English)

    Ednelza de Almeida, Benicio; Ellen Pricilla, Nunes Gadelha; Anette, Talhari; Roberto Moreira da, Silva Jr; Luis Carlos, Ferreira; Mayara Cristina Cordeiro dos, Santos; Marcelo Távora, Mira; Cintia Mara Costa de, Oliveira; Carolina, Talhari; Sinésio, Talhari; Paulo Roberto, Machado; Albert, Schriefer.

    1141-11-01

    Full Text Available FUNDAMENTOS: O Amazonas corresponde a aproximadamente 40% dos casos de leishmaniose do país. Nós reportamos um estudo prospectivo com 180 pacientes de uma unidade de saúde que diagnostica 10% dos casos de leishmaniose da amazônia brasileira, com combinação de métodos diagnóstico em área de alta prev [...] alência de Leishmania guyanensis. OBJETIVOS: avaliar métodos diagnóstico da Leishmaniose em área endêmica para Leishmania Amazonensis. MÉTODOS: Todos os pacientes tiveram exame direto positivo com presença de amastigotas. Foi feita também biópsia cutânea, com realização de exame histológico, reação em cadeia da polimerase e cultura. RESULTADO: A reação em cadeia da polimerase detectou aproximadamente 90% de infecção quando foram usados duas técnicas de amplificação (mini-exon and HSP-70). A reação em cadeia da polimerase com HSP-70 foi mais sensível que a cultura associada à histopatologia. CONCLUSÃO: A melhor combinação foi a reação em cadeia da polimerase com histopatologia, com sensibilidade de 94%. A discrimanação das espécies causadoras de infecção humana nessa região mostrou Leishmania guyanensis em 94% dos casos e Leishmania brasiliensis em 6% Abstract in english BACKGROUND: The Amazon region corresponds to approximately 40% of the cases of leishmaniasis in Brazil. We report a prospective study with 180 patients conducted in a health care unit that diagnoses 10% of the cases of leishmaniasis in the Brazilian Amazon. The study addresses how a combination of p [...] rocedures improves diagnosis in areas with high prevalence of Leishmania guyanensis. OBJECTIVES: to evaluate diagnostic methods in areas with high prevalence of Leishmania guyanensis. METHODS: All subjects were amastigote-positive by direct microscopic examination of lesion scarifications. We conducted skin biopsy and histopathology, polymerase chain reaction and parasite cultivation. RESULTS: Polymerase chain reaction detected almost ninety percent of infections when two amplification protocols were used (mini-exon and HSP-70). HSP-70 specific polymerase chain reaction matched the sensitivity of parasite cultivation plus histopathology. CONCLUSION: The best combination was polymerase chain reaction plus histopathology, which increased diagnostic sensitivity to 94%. Species discrimination by polymerase chain reaction disclosed prevalence of human infections with Leishmania guyanensis of 94% and with Leishmania braziliensis of 6% for this region

  9. Antigenic extracts of Leishmania braziliensis and Leishmania amazonensis associated with saponin partially protects BALB/c mice against Leishmania chagasi infection by suppressing IL-10 and IL-4 production

    Scientific Electronic Library Online (English)

    Rafaella FQ, Grenfell; Eduardo A, Marques-da-Silva; Miriam C, Souza-Testasicca; Eduardo AF, Coelho; Ana Paula, Fernandes; Luís Carlos C, Afonso; Simone A, Rezende.

    2010-09-01

    Full Text Available This study evaluated two vaccine candidates for their effectiveness in protecting BALB/c mice against Leishmania chagasiinfection. These immunogenic preparations were composed of Leishmania amazonensisor Leishmania braziliensisantigenic extracts in association with saponin adjuvant. Mice were given [...] three subcutaneous doses of one of these vaccine candidates weekly for three weeks and four weeks later challenged with promastigotes of L. chagasiby intravenous injection. We observed that both vaccine candidates induced a significant reduction in the parasite load of the liver, while the L. amazonensisantigenic extract also stimulated a reduction in spleen parasite load. This protection was associated with a suppression of both interleukin (IL)-10 and IL-4 cytokines by spleen cells in response to L. chagasiantigen. No change was detected in the production of IFN-?. Our data show that these immunogenic preparations reduce the type 2 immune response leading to the control of parasite replication.

  10. Métodos subsidiários para o diagnóstico da Leishmaniose tegumentar americana (LTA: comparação dos resultados do seqüenciamento de DNA e da PCR-RFLP para determinação da espécie de leishmania em amostras cutâneo-mucosas Subsidiary methods for the diagnosis of American tegumentar leishmaniasis (ATL: comparison of sequencing of DNA and PCR-RFLP for identification of leishmania species in skin samples

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    Flávio C. Barbosa Garcia

    2005-12-01

    Full Text Available FUNDAMENTOS: Métodos moleculares têm-se mostrados mais eficazes para o diagnóstico da LTA. OBJETIVOS: Comparar os resultados da intradermorreação de Montenegro (IRM, presença de leishmania em biópsia (Bc, reação de imunofluorescência indireta (Rifi, seqüenciamento de DNA e PCR-RFLP (-restriction fragment lenght polymorphism para o diagnóstico da LTA. MÉTODOS: Foram estudados 152 pacientes com LTA. Para a PCR em Bc, utilizaram-se primers específicos para seqüência de 120bp do kDNA do minicírculo comum a todas as espécies de leishmanias. O produto da PCR, utilizado para seqüenciamento e para restrição enzimática com Hae III, foi comparado às culturas L. (L. amazonensis e L. (V. braziliensis. RESULTADOS: Houve predomínio do sexo masculino (75%, da cor branca (80% e da profissão urbana (48%. A idade variou de três a 77 anos, com 56,5% entre 21 e 50 anos. 65,8% eram do Estado de São Paulo, prevalecendo a forma cutânea (79,6%. A IRM foi positiva em 73,4%, e a Rifi em 59,7%, enquanto a Bc evidenciou presença de leishmania em 30,6%. A PCR foi positiva em 81,6%, e a PCR-RFLP identificou L. (V. braziliensis como espécie predominante (66%, o que também ocorreu com o seqüenciamento. Comparando PCR-RFLP e seqüenciamento, houve 61% de concordância entre os resultados, mostrando significância da PCR-RFLP para L. (V. braziliensis. CONCLUSÕES: A IRM e a PCR foram estatisticamente equivalentes como métodos subsidiários para o diagnóstico da LTA, a PCR-RFLP e o seqüenciamento também o foram na identificação das espécies de leishmania, o primeiro apresentando menores custo e tempo de execução comparado ao seqüenciamento de DNA.BACKGROUND: ATL is endemic in Brazil, and molecular methods have been shown more effective for its diagnosis. OBJECTIVES: Our purpose was to compare the results of Montenegro’s skin reaction (MR, presence of leishmania in skin biopsy (Bx, indirect immunofluorescence (IIF for leishmania in sera samples, PCR, sequencing of DNA and PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism as subsidiary exams for ATL diagnose. METHODS: 152 patients were studied, with accomplishment of MR, Bx, IIF and PCR for leishmania in skin samples. For PCR, a specific pair of primers for a sequence of 120bp from kDNA minicircle, common to all leishmanias species, was used. The product of PCR was used for DNA sequencing and for RFLP with the enzyme Hae III. The analysis of the restriction pattern was compared to the cultures of L. (L. amazonensis and L. (V. braziliensis. RESULTS: The predominant sex was male (75%, the white color (80% and urban professional occupation (48%. The age varied from 3 to 77 years, with prevalence from 21 to 50 years (56.5%. In relation to the origin, 65.8% was from the state of São Paulo, being the cutaneous form the more prevalent (79.6%. MR was positive in 73.4% and there was presence of leishmania in 30.6% of the samples, while IIF presented 59.7% of positivity. PCR was positive in 81.6% of skin samples, and PCR-RFLP identified L. (V. braziliensis (66% as predominant species, fact that also happened with DNA sequencing, with 64.4% of the positive results for L. (V. braziliensis. Comparing PCR-RFLP and DNA sequencing there was 61% of agreement amongst the results, being significant in PCR-RFLP for L. (V. braziliensis. CONCLUSION: MR and PCR were equivalent as subsidiary methods for the diagnosis of ATL, such as PCR-RFLP and DNA sequencing in the identification of the leishmania species. On the other hand, the method PCR-RFLP presented smaller cost and smaller time of execution compared to the sequencing of DNA.

  11. Métodos subsidiários para o diagnóstico da Leishmaniose tegumentar americana (LTA): comparação dos resultados do seqüenciamento de DNA e da PCR-RFLP para determinação da espécie de leishmania em amostras cutâneo-mucosas / Subsidiary methods for the diagnosis of American tegumentar leishmaniasis (ATL): comparison of sequencing of DNA and PCR-RFLP for identification of leishmania species in skin samples

    Scientific Electronic Library Online (English)

    Flávio C. Barbosa, Garcia; Sandra Silva Rodrigues dos, Santos; Maria Fernanda, Chociay; Ângela C. Rapela, Medeiros; Ana Maria F., Roselino.

    2005-12-01

    Full Text Available FUNDAMENTOS: Métodos moleculares têm-se mostrados mais eficazes para o diagnóstico da LTA. OBJETIVOS: Comparar os resultados da intradermorreação de Montenegro (IRM), presença de leishmania em biópsia (Bc), reação de imunofluorescência indireta (Rifi), seqüenciamento de DNA e PCR-RFLP (-restriction [...] fragment lenght polymorphism) para o diagnóstico da LTA. MÉTODOS: Foram estudados 152 pacientes com LTA. Para a PCR em Bc, utilizaram-se primers específicos para seqüência de 120bp do kDNA do minicírculo comum a todas as espécies de leishmanias. O produto da PCR, utilizado para seqüenciamento e para restrição enzimática com Hae III, foi comparado às culturas L. (L.) amazonensis e L. (V.) braziliensis. RESULTADOS: Houve predomínio do sexo masculino (75%), da cor branca (80%) e da profissão urbana (48%). A idade variou de três a 77 anos, com 56,5% entre 21 e 50 anos. 65,8% eram do Estado de São Paulo, prevalecendo a forma cutânea (79,6%). A IRM foi positiva em 73,4%, e a Rifi em 59,7%, enquanto a Bc evidenciou presença de leishmania em 30,6%. A PCR foi positiva em 81,6%, e a PCR-RFLP identificou L. (V.) braziliensis como espécie predominante (66%), o que também ocorreu com o seqüenciamento. Comparando PCR-RFLP e seqüenciamento, houve 61% de concordância entre os resultados, mostrando significância da PCR-RFLP para L. (V.) braziliensis. CONCLUSÕES: A IRM e a PCR foram estatisticamente equivalentes como métodos subsidiários para o diagnóstico da LTA, a PCR-RFLP e o seqüenciamento também o foram na identificação das espécies de leishmania, o primeiro apresentando menores custo e tempo de execução comparado ao seqüenciamento de DNA. Abstract in english BACKGROUND: ATL is endemic in Brazil, and molecular methods have been shown more effective for its diagnosis. OBJECTIVES: Our purpose was to compare the results of Montenegro’s skin reaction (MR), presence of leishmania in skin biopsy (Bx), indirect immunofluorescence (IIF) for leishmania in sera sa [...] mples, PCR, sequencing of DNA and PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) as subsidiary exams for ATL diagnose. METHODS: 152 patients were studied, with accomplishment of MR, Bx, IIF and PCR for leishmania in skin samples. For PCR, a specific pair of primers for a sequence of 120bp from kDNA minicircle, common to all leishmanias species, was used. The product of PCR was used for DNA sequencing and for RFLP with the enzyme Hae III. The analysis of the restriction pattern was compared to the cultures of L. (L.) amazonensis and L. (V.) braziliensis. RESULTS: The predominant sex was male (75%), the white color (80%) and urban professional occupation (48%). The age varied from 3 to 77 years, with prevalence from 21 to 50 years (56.5%). In relation to the origin, 65.8% was from the state of São Paulo, being the cutaneous form the more prevalent (79.6%). MR was positive in 73.4% and there was presence of leishmania in 30.6% of the samples, while IIF presented 59.7% of positivity. PCR was positive in 81.6% of skin samples, and PCR-RFLP identified L. (V.) braziliensis (66%) as predominant species, fact that also happened with DNA sequencing, with 64.4% of the positive results for L. (V.) braziliensis. Comparing PCR-RFLP and DNA sequencing there was 61% of agreement amongst the results, being significant in PCR-RFLP for L. (V.) braziliensis. CONCLUSION: MR and PCR were equivalent as subsidiary methods for the diagnosis of ATL, such as PCR-RFLP and DNA sequencing in the identification of the leishmania species. On the other hand, the method PCR-RFLP presented smaller cost and smaller time of execution compared to the sequencing of DNA.

  12. Vaccination of C57BL/10 mice against cutaneous leishmaniasis using killed promastigotes of different strains and species of Leishmania Vacinação de camundongos C57BL/10 contra leishmaniose com promastigotas mortas de diferentes cepas e espécies de Leishmania

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    Wilson Mayrink

    2002-04-01

    Full Text Available Antigenic extracts from five Leishmania stocks were used to vaccinate C57BL/10 mice. The Leishvacin® and PH8 monovalent vaccine yielded the highest IFN-gamma levels in the supernatants of spleen cell culture from vaccinated animals. Each single strain immunized group showed evidence of protective immunity six months after the challenge with promastigotes of Leishmania (Leishmania amazonensis. No differences were detected between the vaccinated groups. It can be concluded that vaccines composed of single Leishmania stocks can provide protection to C57BL/10 mice against L. (L. amazonensis infection.Estudos anteriores revelaram que uma vacina preparada com promastigotas mortas de cinco cepas de Leishmania pode induzir uma imunidade protetora para a leishmaniose tegumentar americana no homem e em modelos experimentais. Um dos problemas do uso desta vacina é a complexidade de sua composição e a necessidade de se incorporar diferentes cepas de Leishmania. Por esta razão, extratos antigênicos de cada uma das cinco cepas constituintes da vacina foram preparados e usados individualmente em estudos imunológicos com camundongos C57BL/10. A Leishvacin® e a vacina monovalente PH8 induziram os maiores níveis de Interferon-g (IFN-gama detectado no sobrenadante de células esplênicas dos animais vacinados. Cada grupo imunizado com vacinas monovalentes desenvolveram uma imunidade protetora seis meses após a infecção desafio com promastigotas de Leishmania (Leishmania amazonensis e nenhuma diferença estatística foi observada entre os grupos vacinados. Pode-se concluir que vacinas compostas por cepas isoladas de Leishmania protegem camundongos C57BL/10 contra, pelo menos, da infecção por L. (L. amazonensis.

  13. Leishmania mexicana in Proechimys iheringi denigratus Moojen (Rodentia, Echimyidae) in a region endemic for American cutaneous leishmaniasis

    Scientific Electronic Library Online (English)

    Air C., Barretto; Norman E., Peterson; Ednaldo, Lago; Ana C., Rosa; Rosely S.M., Braga; Cesar A.C., Cuba; Julio A., Vexenat; Philip D., Marsden.

    1985-12-01

    Full Text Available Três isolados de Leishmania foram obtidos de cinco entre 27 exemplares do roedor Proechimys iheringi denigratus, capturados na região de Três Braços, na mata atlântica do Estado da Bahia, Brasil. O isolamento desse parasito foi feito através de inoculação de triturado de pele, baço e fígado em patas [...] de hamsters. Em pelo menos um dos casos, (MTB-574), o parasito foi isolado da pele. Metas- tase foi observada nos hamsters inoculados, os parasitos cresceram abundantemente em meios artificiais de cultura e um padrão suprapapilario típico foi obtido em Lutzomyia longipalpis, indicando que o parasito pertence ao complexo L. mexicana. Todos os isolados reagiram positivamente com anticorpos monoclonais de L. m. mexicana e L. m. amazonensis. A análise isoenzimática diferenciou o parasito de isolados padrões de L. m. mexicana. L. m. amazonensis. L. m. aristedesi. L. m. pifanoi. L. m. garnhami e L. m. ssp(Goiás-W. Barbosa). O parasito parece ser uma subespécie de L. mexicana muito próxima à L. m. amazonensis, da qual difere pela menor mobilidade eletroforêtica de GPI, PEP e ALAT. Este e o primeiro registro do isolamento de um parasito do gênero Leishmania em um roedor capturado no Estado da Bahia. Abstract in english Three isolates of Leishmania were recovered from five of 27 specimens of the rodent Proechimys iheringi denigratus Moojen captured near Três Braços in the Atlantic Forest region of Bahia, Brazil. Two of these isolates were recovered from hamsters inoculated with a pooled triturate of liver, spleen a [...] nd skin tissue from apparently healthy P. i. denigratus. The third isolate was recovered from a triturate of only skin tissue from another. Metastasis was observed in the inoculated hamsters, the parasites grew abundantly in artificial media and a typical suprapylarial pattern of infection in Lutzomyia longipalpis was produced indicating that the parasites belong to the Leishmania mexicana complex. All isolates reacted with Leishmania mexicana mexicana and Leishmania mexicana amazonensis monoclonal antibodies. The isoenzyme analysis differentiated these isolates from standard isolates of L. m. mexicana, L. m. amazonensis, L. m. aristedesi, L. m. pifanoi, L. m. garnhami and L. m. ssp.(Goiás-W. Barbosa). These isolates seem to be a subspecies of L. mexicana very closely related to L. m. amazonensis from which they differ by decreased electrophoretic mobility of GPI, PEP and ALAT. This is the first record of the isolation of a parasite of thegenus Leishmania in a rodent captured in the State of Bahia.

  14. Leishmania mexicana in Proechimys iheringi denigratus Moojen (Rodentia, Echimyidae in a region endemic for American cutaneous leishmaniasis

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    Air C. Barretto

    1985-12-01

    Full Text Available Three isolates of Leishmania were recovered from five of 27 specimens of the rodent Proechimys iheringi denigratus Moojen captured near Três Braços in the Atlantic Forest region of Bahia, Brazil. Two of these isolates were recovered from hamsters inoculated with a pooled triturate of liver, spleen and skin tissue from apparently healthy P. i. denigratus. The third isolate was recovered from a triturate of only skin tissue from another. Metastasis was observed in the inoculated hamsters, the parasites grew abundantly in artificial media and a typical suprapylarial pattern of infection in Lutzomyia longipalpis was produced indicating that the parasites belong to the Leishmania mexicana complex. All isolates reacted with Leishmania mexicana mexicana and Leishmania mexicana amazonensis monoclonal antibodies. The isoenzyme analysis differentiated these isolates from standard isolates of L. m. mexicana, L. m. amazonensis, L. m. aristedesi, L. m. pifanoi, L. m. garnhami and L. m. ssp.(Goiás-W. Barbosa. These isolates seem to be a subspecies of L. mexicana very closely related to L. m. amazonensis from which they differ by decreased electrophoretic mobility of GPI, PEP and ALAT. This is the first record of the isolation of a parasite of thegenus Leishmania in a rodent captured in the State of Bahia.Três isolados de Leishmania foram obtidos de cinco entre 27 exemplares do roedor Proechimys iheringi denigratus, capturados na região de Três Braços, na mata atlântica do Estado da Bahia, Brasil. O isolamento desse parasito foi feito através de inoculação de triturado de pele, baço e fígado em patas de hamsters. Em pelo menos um dos casos, (MTB-574, o parasito foi isolado da pele. Metas- tase foi observada nos hamsters inoculados, os parasitos cresceram abundantemente em meios artificiais de cultura e um padrão suprapapilario típico foi obtido em Lutzomyia longipalpis, indicando que o parasito pertence ao complexo L. mexicana. Todos os isolados reagiram positivamente com anticorpos monoclonais de L. m. mexicana e L. m. amazonensis. A análise isoenzimática diferenciou o parasito de isolados padrões de L. m. mexicana. L. m. amazonensis. L. m. aristedesi. L. m. pifanoi. L. m. garnhami e L. m. ssp(Goiás-W. Barbosa. O parasito parece ser uma subespécie de L. mexicana muito próxima à L. m. amazonensis, da qual difere pela menor mobilidade eletroforêtica de GPI, PEP e ALAT. Este e o primeiro registro do isolamento de um parasito do gênero Leishmania em um roedor capturado no Estado da Bahia.

  15. Molecular and parasitological detection of Leishmania spp. in a dipteran of the species Tabanus importunus / Detecção molecular e parasitológica de Leishmania spp. em díptero da espécie Tabanus importunus

    Scientific Electronic Library Online (English)

    Willian Marinho Dourado, Coelho; Katia Denise Saraiva, Bresciani.

    2013-12-01

    Full Text Available A leishmaniose é uma importante zoonose, de caráter crônico, causada por protozoários do gênero Leishmania spp. Esta protozoose tem como principal vetor os flebotomíneos, sendo que, no Brasil, o Lutzomyia longipalpis é a principal espécie incriminada na transmissão da leishmaniose Visceral Americana [...] . A presença do ácido desoxirribonucleico (DNA) do parasito em ectoparasitos, como carrapatos e pulgas, tem gerado especulações quanto a existência de novos vetores no ciclo da leishmaniose. Foi objetivo deste estudo relatar a detecção molecular de Leishmania spp. em uma mutuca da espécie Tabanus importunus que parasitava um cão oligossintomático infectado por Leishmania spp. A análise molecular amplificou o DNA do protozoário na cabeça, na região torácica e no abdomen do tabanídeo, resultando como positivo para complexo Leishmania. Este é o primeiro relato da presença de DNA de Leishmania spp. em insetos dipteros da espécie T. importunus. Abstract in english Leishmaniasis is an important chronic zoonosis caused by protozoa of the genus Leishmania spp. The major vectors of this protozoosis are sand flies, and Lutzomyia longipalpis is considered the main species implicated in the transmission of American Visceral Leishmaniasis in Brazil. The presence of t [...] he parasite's deoxyribonucleic acid (DNA) in ectoparasites such as ticks and fleas has prompted speculations about the existence of new vectors in the cycle of leishmaniasis. The aim of this paper is to report the molecular detection of Leishmania spp. in a horse fly of the species Tabanus importunus which parasitized an oligosymptomatic dog infected with Leishmania spp. Molecular amplification of the protozoan's DNA in the head, thoracic region and abdomen of the tabanid tested positive for Leishmania complex. This is the first report of the presence of DNA from Leishmania spp. in dipterous insects of the species T. importunus.

  16. The action of ionizing radiation on the morphology, physiology and growth of Leishmania Amazonensis, with evaluation of their immunogenic power in experimental models

    International Nuclear Information System (INIS)

    Leishmaniasis is a disease which affects thousands of people in the Tropical regions around the world, is caused by a protozoan of the genus Leishmania spp., with urban and wild mammals acting as reservoirs. In the mammal host, the amastigote form of the parasite infects and multiplies into macrophages. Treatments for leishmaniasis have a high cost and are long lasting, frequently resulting in therapy interruption. This procedure culminates with a selection of resistant parasite strains, inducing tolerance to the therapy. Either the control of vectors or the mammal host are difficult due the social and economic implications. Thus, the search for alternatives treatments against these protozoans have been stimulated. The gamma radiation (60CO) shown to be an efficient toll to kill these parasites maintaining their immunogenicity. Cellular viability, Electronically microscopy and Multiplex-PCR techniques showed that, after irradiation, the parasites had their growth inhibited by cytoplasmatic and nucleic material disorganisation, appointing the gamma radiation as important in terms of immunogens improvement. (author)

  17. Infective stages of Leishmania in the sandfly vector and some observations on the mechanism of transmission Formas infectante de Leishmania no vetor flebotomíneo e algumas observações sobre o mecanismo de transmissão

    Directory of Open Access Journals (Sweden)

    Ralph Lainson

    1987-09-01

    Full Text Available Infective stages of Leishmania (Leishmania amazonensis, capable of producing amastigote infections in hamster skin, were shown to be present in the experimentally infected sandfly vector Lutzomyia flaviscutellata 15, 25, 40, 49, 70, 96 and 120 hours after the flies had received their infective blood-meal. Similarly, infective stages of Leishmania (L. chagasi were demonstrated in the experimentally infected vector Lu. longipalpis examined 38, 50, 63, 87, 110, 135, 171 and 221 hours following the infective blood-meal, by the intraperitoneal inoculation of the flagellates into hamsters. The question of whether or not transmission by the bite of the sandfly is dependent on the presence of [quot ]metacyclic[quot ] promastigotes in the mouthparts of the vector is discussed.Foi demonstrado através de infecção experimental, que estágios infectivos de Leishmania (L. amazonensis, capazes de produzir infecção na pele do hamster, encontram-se presentes no vetor flebotomíneo Lutzomyia flaviscutellata 15, 25, 40, 49, 70, 96 e 120 horas após o inseto ter recebido sua refeição sangüínea infectiva. Da mesma maneira, foi comprovada a presença de estágios infectivos de L. (L. chagasi em exemplares do vetor Lu. longipalpis, examinados 38, 50, 63, 87, 110, 135, 171 e 221 horas após o repasto sangüíneo infectivo - através da inoculação em hamster por via intraperitoneal dos flagelados obtidos desses fle botomíneos. A questão sobre a transmissão do gênero Leishmania pelo flebotomíneo ser ou não dependente da presença de promastigotos "metacíclios" na proboscis do vetor, é discutida.

  18. ALTERAÇÕES DA MATRIZ EXTRACELULAR ESPLÊNICA EM CÃES NATURALMENTE INFECTADOS COM Leishmania (Leishmania) infantum chagasi / CHANGES IN THE SPLENIC EXTRACELLULAR MATRIX IN DOGS NATURALLY INFECTED WITH Leishmania (Leishmania) infantum chagasi

    Scientific Electronic Library Online (English)

    Nathálya dos Santos, Martins; Glaucia Barbosa, Coelho; Larissa Sarmento dos, Santos; Rudson Almeida de, Oliveira; Ana Lúcia Abreu, Silva; Ferdinan Almeida, Melo.

    2015-03-01

    Full Text Available Objetivou-se estudar as alterações da matriz extracelular no baço de cães naturalmente infectados com Leishmania (Leishmania) infantum chagasi correlacionando-as com aspectos clínicos, histopatológicos e parasitológicos. Foram utilizados 18 cães, divididos em três grupos: seis animais não infectados [...] (grupo controle) e doze animais infectados. Todos sem raça e idade definidas, provenientes da região do Município de São Luis-MA. Cortes parafinados do baço foram corados pela Hematoxilina e Eosina (H&E); Prata amoniacal de Gomori, para marcação das fibras reticulares e pela técnica Imuno-histoquímica da estreptoavidina-peroxidase para detecção de formas amastigotas de Leishmania. As análises morfométricas foram feitas utilizando-se o programa KS300 e o sistema de análise de imagens Kontron Elektronic/Carl Zeiss, Germany. Os resultados mostram que há um aumento significativo da deposição de fibras colágenas no baço quando comparadas aos animais controles, revelando diferenças significativas entre os animais sintomáticos e assintomáticos. Encontraram-se correlações positivas entre a presença do parasitismo tecidual e a deposição de colágeno. Os animais sintomáticos apresentaram uma maior deposição de colágeno no baço, que pode estar associada ao maior parasitismo tecidual encontrado. Os resultados demonstram que na leishmaniose visceral canina há uma fibrogênese intensa no baço, sendo esta associada ao parasitismo tecidual e a processos degenerativos decorrentes da doença. Abstract in english The aim of this study was to study the changes in the splenic extracellular matrix of dogs naturally infected with Leishmania (Leishmania) infantum chagasi and its correlation to clinical, histopathological, and parasitological aspects. Eighteen dogs were used, separated into three groups: six non-i [...] nfected animals (control group) and twelve infected animals. The dogs had undefined breed and age, from the township region of São Luís-MA. Paraffined slices of the spleen were stained with Hematoxilin and Eosin (H&E); Gomori’s ammoniacal Silver, to mark reticular fibers; and the Immunohistochemistry technique of streptavidin peroxidase to detect amastigote forms of Leishmania. The morphometrical analyses were done using the KS300 program and the images analysis system Kontron Elektronic/Carl Zeiss, Germany. The results showed that there is a significant increase in the deposition of collagen fibers in the spleen, compared to control animals, showing significant differences for symptomatic and asymptomatic animals. Positive correlations were found between the presence of the parasite in the tissue and collagen deposition. Symptomatic animals showed higher collagen deposition in the spleen, which can be associated to the high parasitism found in the tissue. The results showed that there is an intense fibrogenesis in the spleen in the canine visceral leishmaniasis, thus being associated to the parasitism of the tissue and the degenerative processes of the disease.

  19. Four new species of Euphyllodromia (Ectobiidae, Pseudophyllodromiinae) from the Amazon region (Brazil) and description of the genitalia of E. amazonensis Rocha e Silva, 1984 / Quatro novas espécies de Euphyllodromia (Ectobiidae, Pseudophyllodromiinae) da região amazônica (Brasil) e descrição da genitália de E. amazonensis Rocha e Silva, 1984

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    Sonia Maria, Lopes; Leonardo de Oliveira Cardoso da, Silva.

    2012-12-01

    Full Text Available Quatro novas espécies de Euphyllodromia Shelford, 1908 (E. spathulata, E. nigromaculata, E. neoelegans e E. spiculata) são descritas. As genitálias do macho das mesmas são ilustradas. A genitália da fêmea de E. spiculata e E. nigromaculata são também ilustradas. Caracteres diagnósticos de cabeça, tó [...] rax e abdomen de E. amazonensis Rocha e Silva, 1984 são redescritos, ilustrados e associados com a descrição da genitália do macho e da fêmea descritos pela primeira vez. Uma chave inclui as espécies aqui mencionadas. Abstract in english Four new species of Euphyllodromia Shelford, 1908 (E. spathulata, E. nigromaculata, E. neoelegans and E. spiculata) are described. Their male genitalia are illustrated. The female genitalia of E. spiculata and E. nigromaculata are also illustrated. Diagnostic characters of the head, thorax and abdom [...] en of E. amazonensis Rocha e Silva, 1984 are reiterated, illustrated and combined with the description of the male and female genitalia for the first time. A key is provided to include the species treated here.

  20. Kinetics of growth of Leishmania (Leishmania) chagasi cycle in McCoy cell culture / Cinéticas de crescimento do ciclo da Leishmania (Leishmania) chagasi em cultura de células McCoy

    Scientific Electronic Library Online (English)

    Yeda L., Nogueira; Paulo M., Nakamura; Eunice A. B., Galati.

    2006-12-01

    Full Text Available Cinéticas de crescimento de Leishmania realizadas in vitro após a internalização da forma promastigota na célula e a ocorrência da transformação do parasito na forma amastigota foram descritas por vários autores, seja com a utilização de explantes de macrófagos em células de baço de hamster ou atual [...] mente da célula de linhagem de macrófago humano U937. Aliando a microscopia à descrição das inter-relações morfológicas e à síntese de moléculas específicas foi possível esclarecer pontos sobre a biologia do parasito. O presente estudo mostra o acompanhamento do ciclo de crescimento da Leishmania chagasi em uma cinética realizada com células de linhagem McCoy, no período de 144 horas. Durante o processo, as transformações morfológicas foram reveladas pela reação de imunofluorescência indireta (RIFI) e as moléculas liberadas no meio extracelular foram observadas pelo método de SDS-PAGE, em intervalos de 24 horas no período de 144 horas. Observou-se que nas primeiras 72 horas, a forma promastigota da L. chagasi fica aderida à membrana das células com aspecto arredondado (amastigota-like). Em 96 horas as células infectadas apresentaram alterações morfológicas; em 120 horas, as células liberaram, para o meio extracelular, antígenos fluorescentes solúveis; e em 144 horas foram observadas novas formas alongadas dos parasitos como se fossem promastigotas. No SDS-PAGE, proteínas com pesos moleculares específicos são observadas em cada ponto da cinética, mostrando que a célula McCoy parece mimetizar o macrófago e que pode ser um modelo útil para o estudo da infecção do binômio leishmânia/célula. Abstract in english The kinetics of growth of Leishmania performed in vitro after internalization of the promastigote form in the cell and the occurrence of the transformation of the parasite into the amastigote form have been described by several authors. They used explants of macrophages in hamster spleen cell cultur [...] e or in a human macrophage lineage cell, the U937. Using microscopy, the description of morphologic inter-relationship and the analysis of the production of specific molecules, it has been possible to define some of the peculiarities of the biology of the parasite. The present study shows the growth cycle of Leishmania chagasi during the observation of kinetic analysis undertaken with a McCoy cell lineage that lasted for a period of 144 hours. During the process, the morphologic transformation was revealed by indirect immunofluorescence (IF) and the molecules liberated in the extra cellular medium were observed by SDS-PAGE at 24-hour intervals during the whole 144-hour period. It was observed that in the first 72 hours the promastigote form of L. chagasi adhered to the cell membranes and assumed a rounded (amastigote-like) form. At 96 hours the infected cells showed morphologic alterations; at 120 hours the cells had liberated soluble fluorescent antigens into the extra cellular medium. At 144 hours, new elongated forms of the parasites, similar to promastigotes, were observed. In the SDS-PAGE, specific molecular weight proteins were observed at each point of the kinetic analysis showing that the McCoy cell imitates the macrophage and may be considered a useful model for the study of the infection of the Leishmania/cell binomial.

  1. Diagnosis of Leishmania infantum infection by Polymerase Chain Reaction in wild mammals / Diagnóstico de infecção por Leishmania infantum pela reação em cadeia da polimerase em mamíferos silvestres

    Scientific Electronic Library Online (English)

    Mayara C., Lombardi; Andréia P., Turchetti; Herlandes P., Tinoco; Angela T., Pessanha; Semiramis A., Soave; Marcelo C.C., Malta; Tatiane A., Paixão; Renato L., Santos.

    1243-12-01

    Full Text Available A leishmaniose visceral é uma doença infecciosa crônica de mamíferos causada, no Brasil, pelo protozoário Leishmania infantum (sinonímia: Leishmania chagasi) e transmitida pelo flebótomo Lutzomyia longipalpis. Trata-se de uma zoonose endêmica em muitas regiões do Brasil, inclusive em Belo Horizonte, [...] Minas Gerais. Em centros urbanos, leishmaniose visceral acomete principalmente o cão doméstico. Entretanto, L. infantum já foi diagnosticada em outras espécies, incluindo canídeos e primatas de cativeiro em zoológicos. Este estudo buscou avaliar a presença do DNA deste agente em animais de cativeiro e de vida livre da Fundação Zoobotânica de Belo Horizonte através da reação em cadeia da polimerase. Foram analisadas oitenta e uma amostras de sangue oriundas de primatas, carnívoros, ruminantes, edentatos, marsupial e herbívoro de estômago simples. Três primatas Alouatta guariba (bugio marrom) e dois canídeos Speothos venaticus (cachorro-do-mato-vinagre), foram positivos, demonstrando a importância do controle da leishmaniose em áreas endêmicas com a finalidade de conservar a fauna silvestre mantida em cativeiro. Abstract in english Visceral leishmaniasis is a chronic infectious disease caused by Leishmania infantum (synonym: Leishmania chagasi) and transmitted by the sandfly Lutzomyia longipalpis in Brazil. It is an endemic zoonosis in several regions of the country, including Belo Horizonte (State of Minas Gerais). In urban a [...] reas, the domestic dog is susceptible and considered the most important animal reservoir. However, L. infantum has been previously diagnosed in other species, including captive primates and canids. This study aimed to evaluate the presence of the agent DNA in captive animals as well as some free ranging animals from the Zoo-Botanical Foundation of Belo Horizonte by Polymerase Chain Reaction. Eighty one blood samples from primates, carnivores, ruminants, edentates, marsupial, and a monogastric herbivore were analyzed. Three primates Alouatta guariba (brown howler monkey), and two canids Speothos venaticus (bush dog) were positive, demonstrating the importance of leishmaniasis control in endemic areas for preservation of wildlife species in captivity.

  2. Evaluation of HIV-Leishmania co-infection in patients from the northwestern Paraná State, Brazil = Avaliação da co-infecção HIV-Leishmania em pacientes da região noroeste do Estado do Paraná, Brasil

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    Élide Aparecida Oliveira

    2011-01-01

    Full Text Available Leishmaniasis occurs throughout the world and is one of the opportunistic infections that attack HIV-infected individuals. Few data are available on American cutaneous leishmaniasis (ACL in HIV-infected patients. Current research investigates the occurrence ofHIV-Leishmania co-infection in HIV-infected individuals in an endemic region in Southern of Brazil. A non-randomized transversal investigation, molecular and serum epidemiologic type, on the occurrence of ACL in 169 HIV-infected patients was undertaken. The patients were followed up at the Integrated Nucleus of Health of the city Maringá, Southern of Brazil. Results showed that 13 (7.7% of the HIV-infected patients also presented Leishmania (Viannia DNA, detectable in blood by PCR. Serology, direct research, culture and PCR in skin material produced negative results. PCR positiveness for Leishmania was not associated with CD4 T lymphocytes count, opportunistic disease, treatment, use of proteases inhibitors, tattooing/piercing or use of injectable drugs, residential environment or previous ACL history. Results show that HIVinfected patients who live in endemic areas may reveal Leishmania DNA in the blood without any ACL symptoms. Above findings may be attributed to anti-retrovirus medicine that controls viral replication and maintains the functionality of the immune system and to a possible anti- Leishmania activity of these drugs.As leishmanioses ocorrem em todo o mundo e são infecções oportunistas que afetam indivíduos portadores do vírus HIV. Este estudo investigou a ocorrência da co-infecção HIV-Leishmania em portadores do HIV numa região endêmica para LTA do Sul do Brasil. Foi realizado estudo transversal, não randomizado, utilizando metodologia molecular e sorológica, sobre a ocorrência de LTA em 169 portadores do HIV. Foram estudados pacientes atendidos no Núcleo Integrado de Saúde de Maringá, Paraná, Sul do Brasil. Observou-se que 13 (7,7% dos pacientes infectados pelo HIV também apresentavam o DNA de Leishmania (Viannia, detectável no sangue por PCR. A sorologia, pesquisa direta de Leishmania, cultura e PCR de lesões de pele foram negativas. A positividade da PCR não estava associada à contagem de linfócitos T CD4+, doença oportunista, tratamento, uso de inibidores de protease, tatuagem, uso de drogas injetáveis, ambiente da residência ou história prévia de LTA. Os resultados mostraram que indivíduos portadores do vírus HIV que residem em área endêmica podem apresentar o DNA de Leishmania sem manifestar sintomas de LTA. Estes resultados podem ser atribuídos a ação dos medicamentos anti retrovirais que controlam a replicação viral mantendo a integridade do sistema imunológico ou a uma possível atividade anti-Leishmania destas drogas.

  3. Assessment of PCR in the detection of Leishmania spp in experimentally infected individual phlebotomine sandflies (Diptera: Psychodidae: Phlebotominae) Avaliação do PCR na investigação de Leishmania spp em flebotomíneos experimentalmente infectados (Diptera: Psychodidae: Phlebotominae)

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    Érika M. MICHALSKY; FORTES-DIAS Consuelo L.; Paulo F.P. PIMENTA; Secundino, Nágila F. C.; Edelberto S. DiaS

    2002-01-01

    DNA amplification by the polymerase chain reaction (PCR) was applied in the investigation of the presence of Leishmania (Kinetoplastida: Trypanosomatidae) parasites in single phlebotomine sandflies. Three phlebotomine/parasite pairs were used: Lutzomyia longipalpis/Leishmania chagasi, Lutzomyia migonei/Leishmania amazonensis and Lutzomyia migonei/Leishmania braziliensis, all of them incriminated in the transmission of visceral or cutaneous leishmaniasis. DNA extraction was performed with whol...

  4. Conjunctival swab PCR to detect Leishmania spp. in cats / Uso da PCR de suabe conjuntival para detecção de Leishmania spp. em gatos

    Scientific Electronic Library Online (English)

    Trícia Maria Ferreira de Sousa, Oliveira; Vanessa Figueredo, Pereira; Graziella Ulbricht, Benvenga; Maria Fernanda Alves, Martin; Julia Cristina, Benassi; Diogo Tiago da, Silva; Wilma Aparecida, Starke-Buzetti.

    2015-06-01

    Full Text Available A importância do cão como fonte de infecção da leishmaniose visceral já é conhecida, mas o papel dos gatos como reservatórios das leishmanioses ainda não está totalmente esclarecido. O presente estudo avaliou a eficácia da PCR de suabe conjuntival (PCR-SC) na detecção de gatos infectados por Leishma [...] nia spp. Foram encontrados sete (13,5%) gatos positivos para Leishmania spp. na PCR de suabe conjuntival, dentre 52 animais de Pirassununga - SP e Ilha Solteira - SP testados. Sendo positivos 28,6% (02/07) dos gatos do município de Pirassununga e 11,1% (5/45) dos gatos do município de Ilha Solteira. Os resultados demonstraram que o suabe de conjuntiva ocular foi capaz de detectar gatos infectados por esse protozoário. A coleta de amostras da conjuntiva mostrou ser um método simples, menos invasivo e pouco estressante para os gatos e seus proprietários, o que pode facilitar estudos sobre a frequência e distribuição da leishmaniose felina. Abstract in english The relevance of the dog as a source of visceral leishmaniasis infection is known, but the role of cats as reservoir hosts for leishmaniasis is not yet fully clear. This study assessed the efficacy of conjunctival swab PCR (CS-PCR) in the detection of cats infected by Leishmania spp. The results wer [...] e seven (13.5%) cats positive for Leishmania spp. in the PCR, in 52 cats tested from Pirassunuga-SP and Ilha Solteira-SP. From the city of Pirassununga – SP 28.6% (2/7) were positive and from the city of Ilha Solteira – SP 11.1% (5/45) were positive. The results showed that CS-PCR was capable of detecting cats infected by this protozoan. Conjunctival swab samples proved easier to perform in cats, which might facilitate studies on the frequency and distribution of feline leishmaniasis.

  5. Cura espontânea da leishmaniose causada por Leishmania Viannia Braziliensis em lesões cutâneas

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    Jackson Maurício Lopes Costa

    1990-12-01

    Full Text Available Os autores relatam que durante 14 anos de trabalho clínico em campo, realizado nas comunidades de Três Braços e Corte de Pedra, Bahia, acompanharam 1.416 pacientes portadores de Leishmaniose Tegumentar Americana, cuja espécie envolvida na transmissão, é predominantemente a Leishmania Viannia brasilienses. A terapêutica utilizada rotineiramente nos casos é o antimoniato-N-metilglucamina (Glucantime. Contudo, 16 pacientes do sexo masculino recusaram-se a utilizar a medicação e 6 do sexo feminino encontravam-se em período gestacional, portanto não utilizaram o medicamento. Estes pacientes foram acompanhados por um período entre 4 a 12 anos, a partir do diagnóstico. Observou-se que em 9 pacientes (40,9% desta casuística, o tempo de cicatrizaçâo após o aparecimento da lesão, pode ser calculado em 6 meses de evolução. Quando se eleva a observação para 12 meses, temos que 19 pacientes (86,3% cicatrizaram suas lesões neste período. Em 3 casos (13,6% as lesões permaneceram ativas por mais de 12 meses. Conclui-se que os determinantes da cicatrizaçâo natural das lesões produzidas por Leishmania Viannia Braziliensis permanecem desconhecidos, dificultando para nós entendermos e compararmos aos efeitos das drogas utilizadas no tratamento da leishmaniose tegumentar.In field clinics in the comunities of Três Braços and Corte de Pedra, Bahia, we have attended 1.416 patients with tegumentary leishmaniasis in fourteen years, the predomi nant species in transmission is Leishmania Viannia brasiliensis (LVB. Because of the danger of metastasis with this infection treatment was routinely recomended with Glucantime. However sixteen patients refused injection therapy and six women were pregnant when seen and not treated. All patients were followed up in our clinic. All these patients closed their skin ulcers although one subsequently relapsed. Patients were followed up for variable periods (four to twelve years, after the diagnosis. In nine patients (40,9% of the cohort, the time to healing after initiation of the lesion was calculated as six months of evolution. At twelve months, nineteen patients (86,3% had complete healing of their lesions. In three patients an active lesion was present for longer than one year. The determinants of this variable natural evolution of human LVB lesion remains completely unknown. It is difficult for us to understand and compare the effects of therapeutic agents in mucocutaneous leishmaniasis.

  6. Análise histomorfométrica da matriz extracelular do linfonodo poplíteo de cães naturalmente infectados por Leishmania (L. chagasi

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    Kris Régia J. Kondo

    2009-08-01

    Full Text Available Nas Américas, a leishmaniose visceral canina é causada por Leishmania (Leishmania chagasi, um protozoário intracelular obrigatório do sistema fagocítico mononuclear; as principais alterações histológicas associadas a essa doença ocorrem nos em órgãos linfóides. Apesar de o cão ser considerado o principal mantenedor e disseminador da leishmaniose no ambiente urbano, são escassos estudos dos aspectos histopatológicos e histomorfométricos, em cães naturalmente infectados com L. chagasi, que investiguem a interação entre o parasito e a matriz extracelular. Este estudo visou caracterizar e quantificar as alterações dos componentes celulares e da matriz extracelular (colágenos I e III do linfonodo poplíteo de 22 cães com infecção natural por L. chagasi detectada através da reação de imunofluorescência indireta (RIF e compará-las com as alterações encontradas no linfonodo poplíteo de 10 cães não-infectados, negativos na RIF e clinicamente saudáveis. Fragmentos dos linfonodos foram seccionados longitudinalmente, processados rotineiramente para exame histológico e corados por hematoxilina-eosina. Cortes adicionais do mesmo linfonodo incluídos em glicol metacrilato foram corados pelo azul de toluidina para histomorfometria. Linfonodos de cães infectados apresentaram linfadenopatia generalizada, aumento do tamanho e do número dos folículos linfóides, hipertrofia da cápsula e hiperplasia linfóide significativa. Nos linfonodos de cães do grupo infectado, a análise quantitativa de fibras colágenas mostrou significativo predomínio do colágeno I sobre o colágeno III. Esses resultados demonstram que cães infectados por L. chagasi apresentam degradação dos constituintes da matriz extracelular e conseqüente destruição do arcabouço linfóide, alterando a morfologia do órgão.In the Americas, canine visceral leishmaniasis is caused by Leishmania (Leishmania chagasi, an obligatory intracellular parasite of the phagocytic-monocytic system; the main histological changes associated with this disease occur in the lymphoid organs. Although dogs are considered to be the main carriers and disseminators of leishmaniasis in urban areas, there are few studies on the histopathologic and histomorphometric aspects in dogs naturally infected by L.chagasi analyzing the interaction between parasite and extracellular matrix. The current study characterize and quantify changes in the cellular and extracellular matrix (collagens type I and III components of the popliteal lymph node from of 22 dogs with the natural infection by L. chagasi confirmed by indirect immuno-fluorescence assay (IFA and compare theses findings with those fund in the popliteal lymph node from 10 non-infected dogs, that reacted negative in the IFA, and were clinically healthy. Lymph node fragments were longitudinally sliced and sections were processed for routine histopathology and stained by hematoxylin and eosin. For histomorphometry, additional sections from the same lymph node were fixed in glycol methacrylate and stained with toluidine blue. Lymph nodes from affected dogs were systemically enlarged, had increased numbers of lymphoid follicles, capsule hyperplasia and hypertrophy, and significant hyperplasia of lymphoid cells. In the lymph nodes from infected dogs, quantitative analyses of collagen fibers revealed predominance of type I collagen over type III fibers. These results demonstrate that dogs infected by L.chagasi experience degradation of the extracellular matrix components and consequently destruction of the lymphoid framework, thus altering nodal morphology.

  7. Diagnóstico molecular da taxa de infecção natural de flebotomíneos (Psychodidae, Lutzomyia) por Leishmania sp na Amazônia maranhense / Molecular diagnosis of the natural infection rate due to Leishmania sp in sandflies (Psychodidae, Lutzomyia) in the Amazon region of Maranhão, Brazil

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    Yrla Nívea, Oliveira-Pereira; José Manuel Macário, Rebêlo; Jorge Luiz Pinto, Moraes; Silma Regina Ferreira, Pereira.

    2006-12-01

    Full Text Available A taxa de infecção natural de três diferentes espécies de flebotomíneos por Leishmania foi estudada usando a técnica de reação em cadeia da polimerase. Primers específicos para Leishmania foram designados para examinar se os pools de flebotomíneos estavam infectadas. Um total de 1.100 fêmeas separad [...] as em pools de 10 indivíduos foram examinados, consistindo de 50 Lutzomyia whitmani, 43 Lutzomyia triacantha e 17 Lutzomyia choti. De todos os pools analisados, 4 de Lutzomyia whitmani estavam positivos, mas nenhum pool das duas espécies restantes estava infectado. Deste modo, uma taxa de infecção de 0,4% foi verificada neste estudo. Esta taxa de infecção associada a estudos anteriores sugere que Lutzomyia whitmani transmite Leishmania aos mamíferos em Buriticupu, Maranhão. Abstract in english The natural infection rate due to Leishmania was studied in three different sandfly species using the polymerase chain reaction technique. Leishmania specific primers were designed to examine whether sandfly pools were infected. In total 1,100 female sandflies separated into pools of 10 individuals, [...] consisting of 50 pools of Lutzomyia whitmani, 43 of Lutzomyia triacantha and 17 of Lutzomyia choti, were analyzed. Among all the pools examined, four pools of Lutzomyia whitmani were positive, but none of the pools of the other two species were infected. Thus, a total infection rate of 0.4% was established in this study. A similar infection rate was found in previous studies, suggesting that Lutzomyia whitmani transmits Leishmania to mammals in Buriticupu, Maranhão.

  8. Diagnóstico molecular da taxa de infecção natural de flebotomíneos (Psychodidae, Lutzomyia por Leishmania sp na Amazônia maranhense Molecular diagnosis of the natural infection rate due to Leishmania sp in sandflies (Psychodidae, Lutzomyia in the Amazon region of Maranhão, Brazil

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    Yrla Nívea Oliveira-Pereira

    2006-12-01

    Full Text Available A taxa de infecção natural de três diferentes espécies de flebotomíneos por Leishmania foi estudada usando a técnica de reação em cadeia da polimerase. Primers específicos para Leishmania foram designados para examinar se os pools de flebotomíneos estavam infectadas. Um total de 1.100 fêmeas separadas em pools de 10 indivíduos foram examinados, consistindo de 50 Lutzomyia whitmani, 43 Lutzomyia triacantha e 17 Lutzomyia choti. De todos os pools analisados, 4 de Lutzomyia whitmani estavam positivos, mas nenhum pool das duas espécies restantes estava infectado. Deste modo, uma taxa de infecção de 0,4% foi verificada neste estudo. Esta taxa de infecção associada a estudos anteriores sugere que Lutzomyia whitmani transmite Leishmania aos mamíferos em Buriticupu, Maranhão.The natural infection rate due to Leishmania was studied in three different sandfly species using the polymerase chain reaction technique. Leishmania specific primers were designed to examine whether sandfly pools were infected. In total 1,100 female sandflies separated into pools of 10 individuals, consisting of 50 pools of Lutzomyia whitmani, 43 of Lutzomyia triacantha and 17 of Lutzomyia choti, were analyzed. Among all the pools examined, four pools of Lutzomyia whitmani were positive, but none of the pools of the other two species were infected. Thus, a total infection rate of 0.4% was established in this study. A similar infection rate was found in previous studies, suggesting that Lutzomyia whitmani transmits Leishmania to mammals in Buriticupu, Maranhão.

  9. The Diverse and Dynamic Nature of Leishmania Parasitophorous Vacuoles Studied by Multidimensional Imaging

    OpenAIRE

    Real, Fernando; Mortara, Renato A.

    2012-01-01

    An important area in the cell biology of intracellular parasitism is the customization of parasitophorous vacuoles (PVs) by prokaryotic or eukaryotic intracellular microorganisms. We were curious to compare PV biogenesis in primary mouse bone marrow-derived macrophages exposed to carefully prepared amastigotes of either Leishmania major or L. amazonensis. While tight-fitting PVs are housing one or two L. major amastigotes, giant PVs are housing many L. amazonensis amastigotes. In this study, ...

  10. Estado atual da leishmaniose cutânea difusa (LCD no Estado do Maranhão: II. aspectos epidemiológicos, clínico-evolutivos

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    Jackson Maurício Lopes Costa

    1992-06-01

    Full Text Available Os Autores fazem um estudo retrospectivo e prospectivo de 6 pacientes portadores de leishmaniose cutânea difusa, observados no Estado do Maranhão a partir de 1974. Os casos abordados são oriundos de diversas regiões do estado, observando-se em todos eles o envolvimento da leishmania (Leishmania amazonensis, sendo que 5 (84% dos pacientes apresentaram início de doença na 1ª década de vida. Em todos os pacientes envolvidos no estudo, houve relato de lesão inicial nodular única, que, posteriormente, em período variável de tempo, disseminou-se adquirindo outros aspectos. Evolutivamente apresentaram múltiplas lesões nodulares e ulceradas, intradermorreação de Montenegro(- e refratariedade aos esquemas terapêuticos utilizados até ao presente momento.The authors describe a retrospective and prospective study of 6 patients with diffuse cutaneous leishmaniasis observed in the State of Maranhão, since 1974. The patients comefromdifferentruralregions of the state and in all of them Leishmania (Leishmania amazonensis was the cause five of the patients initiated their disease in the first decade of life. All the patients first had a solitary, nodular lesion, that after a variable period of time, disseminated and acquired other aspects. Sequentially the patients presented multiple nodular and ulcerative lesions, negative leishmania skin-lests and a refractory response to the therapeutic schedules used up to the present.

  11. Kinetics of growth of Leishmania (Leishmania) chagasi cycle in McCoy cell culture Cinéticas de crescimento do ciclo da Leishmania (Leishmania) chagasi em cultura de células McCoy

    OpenAIRE

    Yeda L. NOGUEIRA; Paulo M. NAKAMURA; Eunice A B Galati

    2006-01-01

    The kinetics of growth of Leishmania performed in vitro after internalization of the promastigote form in the cell and the occurrence of the transformation of the parasite into the amastigote form have been described by several authors. They used explants of macrophages in hamster spleen cell culture or in a human macrophage lineage cell, the U937. Using microscopy, the description of morphologic inter-relationship and the analysis of the production of specific molecules, it has been possible...

  12. DETECTION OF Leishmania (Viannia) IN Nyssomyia neivai AND Nyssomyia whitmani BY MULTIPLEX POLYMERASE CHAIN REACTION, IN SOUTHERN BRAZIL / Detecção de Leishmania (Viannia) em Nyssomyia neivai e Nyssomyia whitmani por Multiplex Reação em Cadeia da Polimerase, no sul do Brasil

    Scientific Electronic Library Online (English)

    Herintha Coeto, Neitzke-Abreu; Kárin Rosi, Reinhold-Castro; Mateus Sabaini, Venazzi; Regiane Bertin de Lima, Scodro; Alessandra de Cassia, Dias; Thaís Gomes Verzignassi, Silveira; Ueslei, Teodoro; Maria Valdrinez Campana, Lonardoni.

    2014-09-01

    Full Text Available Flebotomíneos transmitem os patógenos das leishmanioses. Foi avaliada a infecção natural de flebotomíneos por Leishmania (Viannia) em municípios do Estado do Paraná, sul do Brasil. Os flebotomíneos foram coletados com armadilhas de Falcão e Shannon. Após dissecação para pesquisa de flagelados no tub [...] o digestório e identificação das espécies, as fêmeas de flebotomíneos foram submetidas a Multiplex Reação em Cadeia da Polimerase (multiplex PCR) para a detecção do fragmento do kDNA de Leishmania (Viannia) e do fragmento do gene IVS6 da cacofonia de flebotomíneos. A análise foi realizada em pools contendo sete a 12 tubos digestórios de fêmeas da mesma espécie. Um total de 510 fêmeas foram analisadas, incluindo nove Migonemyia migonei, 17 Pintomyia fischeri, 216 Nyssomyia neivai e 268 Nyssomyia whitmani. Embora nenhuma fêmea tenha sido encontrada naturalmente infectada com flagelados pela dissecação, o fragmento de DNA de Leishmania (Viannia) foi mostrado por multiplex PCR em uma amostra de Ny. neivai (0,46%) e três amostras de Ny. whitmani (1,12%). Conclui-se que Ny. neivai e Ny. whitmani são suscetíveis à infecção por Leishmania, e que multiplex PCR, devido à sua sensibilidade, especificidade e viabilidade, pode ser utilizada em estudos epidemiológicos para a detecção da infecção natural do inseto vetor. Abstract in english Sandflies transmit pathogens of leishmaniasis. The natural infection of sandflies by Leishmania (Viannia) was assessed in municipalities, in the state of Paraná, in Southern Brazil. Sandflies were collected with Falcão and Shannon traps. After dissection in search of flagellates in digestive tubes a [...] nd identification of the species, female sandflies were submitted to the Multiplex Polymerase Chain Reaction (multiplex PCR) for detection of the fragment of the kDNA of Leishmania (Viannia) and the fragment from the IVS6 cacophony gene region of the phlebotomine insects. The analysis was performed in pools containing seven to 12 guts from females of the same species. A total of 510 female sandflies were analyzed, including nine Migonemyia migonei, 17 Pintomyia fischeri, 216 Nyssomyia neivai, and 268 Nyssomyia whitmani. Although none of the females was found naturally infected by flagellates through dissection, the fragment of DNA from Leishmania (Viannia) was shown by multiplex PCR in one sample of Ny. neivai (0.46%) and three samples of Ny. whitmani (1.12%). It was concluded that Ny. neivai and Ny. whitmani are susceptible to Leishmania infection, and that multiplex PCR can be used in epidemiological studies to detect the natural infection of the sandfly vector, because of its sensitivity, specificity and feasibility.

  13. Characterization of Leishmania infantum species in dogs from the urban area of Cuiabá, State of Mato Grosso, Brazil / Caracterização da espécie Leishmania infantum em cães de área urbana de Cuiabá, Estado do Mato Grosso

    Scientific Electronic Library Online (English)

    Bianca De, Santis; Elizabeth Gloria Oliveira Barbosa, Santos; Elisa, Cupolillo; Renato, Porrozzi; Amanda dos Santos, Cavalcanti; Bárbara Neves dos, Santos; Saulo Teixeira De, Moura; Kellen, Malhado; Sergio Augusto Miranda, Chaves.

    2011-12-01

    Full Text Available INTRODUÇÃO: A leishmaniose visceral apresenta comportamento urbano em algumas cidades brasileiras, sendo os cães domésticos as principais fontes de infecção. Em Cuiabá-MT, a leishmaniose visceral canina foi diagnosticada e caracterizada, como recomendação do Ministério da Saúde. MÉTODOS: Amostras bi [...] ológicas de cães suspeitos foram analisadas por eletroforese de isoenzimas. Foram utilizadas a enzima 6PGDH e a cepa de referência IOC/L0566 (MHOM/BR/1975/M2903) de Leishmania (Leishmania) infantum, como um dos controles. RESULTADOS: A análise eletroforética revelou que os isolados pertenciam à espécie L. (L.) infantum. CONCLUSÕES: Os autores ressaltam a importância da caracterização da espécie, principalmente em cidades com infecção mista, como Cuiabá. Abstract in english INTRODUCTION: Visceral leishmaniasis presents urban behavior in some Brazilian cities, with domestic dogs as the main infection source. In Cuiabá, MT, canine visceral leishmaniasis was diagnosed and characterized as recommended by the Ministry of Health. METHODS: Biological samples from suspected ca [...] nine carriers were analyzed by the isoenzyme electrophoresis technique. The 6PGDH enzyme and reference strain IOC/L0566 (MHOM/BR/1975/M2903) of Leishmania (Leishmania) infantum was used as one of the controls. RESULTS: Electrophoresis analysis revealed that the canine isolates belonged to the species L. (L.) infantum. CONCLUSIONS: The authors emphasize the importance of species characterization, particularly in areas of mixed infection like Cuiabá.

  14. Characterization of Leishmania infantum species in dogs from the urban area of Cuiabá, State of Mato Grosso, Brazil Caracterização da espécie Leishmania infantum em cães de área urbana de Cuiabá, Estado do Mato Grosso

    Directory of Open Access Journals (Sweden)

    Bianca De Santis

    2011-12-01

    Full Text Available INTRODUCTION: Visceral leishmaniasis presents urban behavior in some Brazilian cities, with domestic dogs as the main infection source. In Cuiabá, MT, canine visceral leishmaniasis was diagnosed and characterized as recommended by the Ministry of Health. METHODS: Biological samples from suspected canine carriers were analyzed by the isoenzyme electrophoresis technique. The 6PGDH enzyme and reference strain IOC/L0566 (MHOM/BR/1975/M2903 of Leishmania (Leishmania infantum was used as one of the controls. RESULTS: Electrophoresis analysis revealed that the canine isolates belonged to the species L. (L. infantum. CONCLUSIONS: The authors emphasize the importance of species characterization, particularly in areas of mixed infection like Cuiabá.INTRODUÇÃO: A leishmaniose visceral apresenta comportamento urbano em algumas cidades brasileiras, sendo os cães domésticos as principais fontes de infecção. Em Cuiabá-MT, a leishmaniose visceral canina foi diagnosticada e caracterizada, como recomendação do Ministério da Saúde. MÉTODOS: Amostras biológicas de cães suspeitos foram analisadas por eletroforese de isoenzimas. Foram utilizadas a enzima 6PGDH e a cepa de referência IOC/L0566 (MHOM/BR/1975/M2903 de Leishmania (Leishmania infantum, como um dos controles. RESULTADOS: A análise eletroforética revelou que os isolados pertenciam à espécie L. (L. infantum. CONCLUSÕES: Os autores ressaltam a importância da caracterização da espécie, principalmente em cidades com infecção mista, como Cuiabá.

  15. LA Leishmania spp. COMO ESTRATEGIA DE DIAGNÓSTICO Y TRATAMIENTO DE LA LeishmaniaSIS, UN ARTÍCULO DE REVISIÓN / Leishmania spp. AS A DIAGNOSTIC STRATEGY AND AS A TREATMENT OF LeishmaniaSIS; AN ARTICLE OF REVISION. / A Leishmania spp. COMO ESTRATÉGIA DE DIAGNÓSTICO E TRATAMIENTO DA LeishmaniaSIS, UM ARTIGO DE REVISÃO

    Scientific Electronic Library Online (English)

    Martha Cecilia, Beltrán Cifuentes; Patricia, Durán Ospina; Luisa Fernanda, Corredor Arias.

    2007-09-01

    Full Text Available Algumas enfermidades emergentes e reemergentes têm aumentado de maneira quase indecifrável, quanto ao lugar de origem. Tais são os casos do Mal de Chagas, malária, dengue, febre amarela, raiva e leishmaniose, devido entre outros, a fatores de mobilidade populacional, demográficos, sociais e econômic [...] os que levam microrganismos a gerarem adaptações ao meio mutante, dificultando seu diagnóstico e tratamento por métodos convencionais. Métodos Realizou-se uma busca exaustiva nas bases de dados relacionadas com genômica e proteômica, como o NCBI (National Center for Biotechnology Information), auspiciada pela U.S National Library of Medicine e o National Institute of Health, onde se conta com aceso a PubMed. Resultados Na atualidade aplicam-se técnicas de marcadores moleculares, PCR (Reação em cadeia da polimerasa) que complementam as provas bioquímicas e microbiológicas empregadas comumente no diagnóstico. Conhecendo a expressão genômica destes parasitas, se poderão desenhar métodos novos mais efetivos contra cepas resistentes aos fármacos disponíveis na atualidade e de prevenção rápida. Conclusões Neste artigo se apresenta uma revisão bibliográfica, onde a informação clínica do paciente é determinante para o diagnóstico, o qual pode ser confirmado com técnicas moleculares desenvolvidas em tempo real, para contribuir ao conhecimento molecular da Leishmania spp, como estratégia de diagnóstico e tratamento desta patologia. Abstract in spanish Introducción: Algunas enfermedades emergentes y reemergentes han venido en aumento de manera casi impredecible, en cuanto al sitio de origen. Tal es el caso de la enfermedad de Chagas, malaria, dengue, fiebre amarilla, rabia, Leishmaniasis, debido entre otros a factores de movilidad poblacional, dem [...] ográficos, sociales y económicos que han llevado a que los microorganismos generen adaptaciones al medio cambiante, dificultando su diagnóstico y tratamiento por métodos convencionales. Métodos: Se realizó una búsqueda exhaustiva en las bases de datos relacionadas con genómica y proteómica como el NCBI (National Center for Biotechnology Information), auspiciado por la U.S National Library of Medicine y el National Institute of Health, donde se cuenta con acceso a PubMed Resultados: En la actualidad se han venido aplicando técnicas de marcadores moleculares, PCR (Reacción en Cadena de la Polimerasa) que complementan las pruebas bioquímicas y microbiológicas empleadas comúnmente en el diagnóstico. Conociendo la expresión genómica de estos parásitos, se podrán diseñar métodos nuevos más efectivos contra cepas resistentes a los fármacos disponibles en la actualidad y de prevención temprana. Conclusiones: En este artículo se presenta una revisión bibliográfica, donde la información clínica del paciente es determinante para el diagnóstico, el cual puede ser confirmado con técnicas moleculares desarrolladas en tiempo real, para aportar al conocimiento molecular de la Leishmania spp, como estrategia de diagnóstico y tratamiento de esta patología. Abstract in english Introduction: Some emerging and reemerging infirmities have been increasing in an almost unpredictable manner as far as site of origin. Such is the case with such diseases as Chagas, malaria, dengue, yellow fever, rabies, and Leishmaniasis. Various demographic, social, and economic factors, as well [...] as population mobility have allowed microorganisms to generate adaptations to changing environments and thus make diagnosis and treatment by conventional methods more difficult. Methodology: An exhaustive search was undertaken in the data bases related to genome and protein sequence information found at the NCBI (National Center for Biotechnology Information), part of the United States National Library of Medicine and the National Institutes of Health, all with direct access to PubMed. Results: Today techniques using molecular markers, PCR (Polymerase Chain Reaction), are being used to complement the biochemical and microbiological test

  16. Comparative analysis of the geographic distribution of the histopathological spectrum and Leishmania species of American cutaneous leishmaniasis in Brazil / Análise comparativa da distribuição geográfica do espectro histopatológico e espécies de Leishmania da leishmaniose tegumentar americana no Brasil

    Scientific Electronic Library Online (English)

    Linton Wallis Figueiredo, Souza; Simone Vilas Trancoso, Souza; Ana Cristina Carvalho, Botelho.

    2012-06-01

    Full Text Available FUNDAMENTOS: O conhecimento das relações entre diferenças geográficas específicas e a histopatologia da leishmaniose tegumentar americana é limitada devido à complexidade espacial e temporal da interação hospedeiro-parasito. OBJETIVOS: Descrever a distribuição geográfica do padrão histopatológico da [...] leishmaniose tegumentar americana na forma cutânea localizada e a relação com a espécie de Leishmania. MÉTODOS: Estudo transversal, descritivo e analítico, de uma amostra de 55 pacientes de Montes Claros e 32 de Caratinga, Minas Gerais, comparando com diferentes regiões do Brasil através de avaliações históricas, microregionais e da construção de intervalos de confiança. RESULTADOS: Na forma cutânea da leishmaniose tegumentar americana, foi encontrada uma preponderância de reações exsudativas-celulares nos municípios de Caratinga, leste de Minas Gerais, Montes Claros, norte de Minas Gerais e Uberlândia, Triângulo mineiro, e também nos estados de Mato Grosso e Ceará. As reações exsudativas-necróticas-granulomatosas encontradas foram mais freqüentes em áreas do norte do Brasil, principalmente nos estados do Amazonas e Pará. As reações exsudativas-necróticas foram as formas mais freqüentes de apresentação encontradas em todas as áreas no Brasil quando a predominância de L. braziliensis foi menor que 90% em relação às outras espécies. CONCLUSÕES: Existe uma variação geográfica da resposta inflamatória imune na leishmaniose tegumentar americana. As correlações geográficas entre as espécies predominantes de Leishmania e o espectro histopatológico da leishmaniose tegumentar americana, que até que o presente estudo não tinha sido realizada, permite novas abordagens nos estudos de subpopulações de Leishmania em áreas com uma predominância de uma espécie e provê evidência das variações no comportamento biológico de diferentes espécies. Abstract in english BACKGROUND: Knowledge of the relationship between specific geographical differences and histopathology of the American cutaneous leishmaniasis is limited because host-parasite interactions in space and time are complex. OBJECTIVE: To describe the geographic analysis of the histopathological pattern [...] of localized American cutaneous leishmaniasis and the relationship with Leishmania species. METHODS: A cross-sectional, descriptive and analytical study of a sample consisting of 55 patients of municipal districts of Montes Claros and 32 of Caratinga, Minas Gerais, by comparing with other endemic regions in Brazil, assessing historical and microregional data and developing confidence intervals. RESULTS: A preponderance of cellular exudative reactions in the cutaneous form of American cutaneous leishmaniasis was found in the municipal districts of Caratinga, east of Minas Gerais, Montes Claros, north of Minas Gerais and Uberlândia, Triangulo Mineiro, and also in the states of Mato Grosso and Ceara. Necrotic and exudative granulomatous reactions were found to be more frequent in the northern areas, mainly in the states of Amazonas and Para. Necrotic and exudative reactions were the most frequent form of presentation found throughout Brazil when the predominance of L. braziliensis was below 90% in relation to other species. CONCLUSION: There is a geographic variation of the immune inflammatory response in American cutaneous leishmaniasis. Geographical correlations between the predominant species of Leishmania and the most frequent forms of histopathological presentation of American cutaneous leishmaniasis, which until the present study had not been performed, enables new approaches to the study of Leishmania subpopulations in areas with a predominance of one species and provides evidence of variations in the biological behavior of different species.

  17. Immunogold labeling and cerium cytochemistry of the enzyme ecto-5'-nucleotidase in promastigote forms of Leishmania species

    Scientific Electronic Library Online (English)

    Suzana, Corte-Real; Renato, Porrozzi; Maria de Nazareth Leal de, Meirelles.

    1993-09-01

    Full Text Available We have applied both enzyme cytochemistry and immunological labeling techniques to characterize the enzyme 5'-nucleotidase (5'-Nase), at the ultrastructural level, in promastigote forms of four Leishmania species: Leishmania amazonensis, Leishmania mexicana, Leishmania donovani and Leishmania chagas [...] i. The cerium phosphate staining was localized at the surface of the cell body, the flagellum and the flagellar pocket membranes of all the parasites studied. The immunogold labelling technique confirmed these results. In this report we localized 5'-Nase in L. chagasi and L. amazonensis which have been implicated respectively in visceral and cutaneous forms of leishmaniasis. In addition, we confirmed the localization of this phosphomonoesterase in the other two species studied. The superior quality of the images, obtained with both methodologies, confirms that these parasites possess mechanisms capable of hydrolyzing nucleotide monophosphates, and that the expression of 5'-Nase is associated with the outer surface of the plasma membrane.

  18. Leishmaniose tegumentar americana causada por Leishmania (Viannia braziliensis, em área de treinamento militar na Zona da Mata de Pernambuco

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    Andrade Maria S.

    2005-01-01

    Full Text Available Este estudo tem como objetivo geral caracterizar a epidemiologia da leishmaniose tegumentar americana em unidade de treinamento militar, localizada no Estado de Pernambuco. Entre 2002 e 2003, vinte e três casos foram diagnosticados através de exame clínico, detecção do parasita e teste de intradermoarreação de Montenegro. Sete amostras de Leishmania (Viannia braziliensis foram isoladas destes pacientes, identificadas através de reações com anticorpos monoclonais específicos e perfil eletroforético com isoenzimas. Um inquérito epidemiológico de prevalência da infecção por IDRM foi realizado na população que realizou treinamento neste período, no qual foi identificada uma prevalência de 25,3% de infecção. Os dados obtidos, associados com achados prévios nesta área, apresentam evidências da manutenção de um ciclo enzoótico, com a ocorrência de surtos periódicos de leishmaniose tegumentar americana posteriormente à realização de treinamentos nas áreas de floresta Atlântica remanescente.

  19. Métodos subsidiários para o diagnóstico da Leishmaniose tegumentar americana (LTA): comparação dos resultados do seqüenciamento de DNA e da PCR-RFLP para determinação da espécie de leishmania em amostras cutâneo-mucosas Subsidiary methods for the diagnosis of American tegumentar leishmaniasis (ATL): comparison of sequencing of DNA and PCR-RFLP for identification of leishmania species in skin samples

    OpenAIRE

    Barbosa Garcia, Fla?vio C.; Sandra Silva Rodrigues dos Santos; Maria Fernanda Chociay; Rapela Medeiros, A?ngela C.; Roselino, Ana Maria F.

    2005-01-01

    FUNDAMENTOS: Métodos moleculares têm-se mostrados mais eficazes para o diagnóstico da LTA. OBJETIVOS: Comparar os resultados da intradermorreação de Montenegro (IRM), presença de leishmania em biópsia (Bc), reação de imunofluorescência indireta (Rifi), seqüenciamento de DNA e PCR-RFLP (-restriction fragment lenght polymorphism) para o diagnóstico da LTA. MÉTODOS: Foram estudados 152 pacientes com LTA. Para a PCR em Bc, utilizaram-se primers específicos para seqüência de 120bp ...

  20. Leishmaniose tegumentar americana causada por Leishmania (Viannia) braziliensis, em área de treinamento militar na Zona da Mata de Pernambuco / American tegumentary leishmaniasis caused by Leishmania (Viannia) braziliensis in military training area of Zona da Mata in Pernambuco

    Scientific Electronic Library Online (English)

    Maria S., Andrade; Maria E. F., Brito; Salomão Thomaz da, Silva; Bruna S., Lima; Éricka L., Almeida; Elisângela L., Albuquerque; José F., Marinho Júnior; Edna, Ishikawa; Elisa, Cupolillo; Sinval P., Brandão-Filho.

    2005-05-01

    Full Text Available Este estudo tem como objetivo geral caracterizar a epidemiologia da leishmaniose tegumentar americana em unidade de treinamento militar, localizada no Estado de Pernambuco. Entre 2002 e 2003, vinte e três casos foram diagnosticados através de exame clínico, detecção do parasita e teste de intradermo [...] arreação de Montenegro. Sete amostras de Leishmania (Viannia) braziliensis foram isoladas destes pacientes, identificadas através de reações com anticorpos monoclonais específicos e perfil eletroforético com isoenzimas. Um inquérito epidemiológico de prevalência da infecção por IDRM foi realizado na população que realizou treinamento neste período, no qual foi identificada uma prevalência de 25,3% de infecção. Os dados obtidos, associados com achados prévios nesta área, apresentam evidências da manutenção de um ciclo enzoótico, com a ocorrência de surtos periódicos de leishmaniose tegumentar americana posteriormente à realização de treinamentos nas áreas de floresta Atlântica remanescente. Abstract in english The aim of work was to study the epidemiology of American tegumentary leishmaniasis in a military training unit situated in Zona da Mata region of Pernambuco State. Between 2002 and 2003 twenty-three cases were notified by clinical exam, detection and/or isolation of parasite and Montenegro skin tes [...] t. Seven stocks of Leishmania (Viannia) braziliensis were obtained from patients, identified by a panel of specific monoclonal antibodies and isoenzymatic electrophoresis profiles. An epidemiologic survey on prevalence of infection was carried out by Montenegro skin test in the population that underwent training activities during the same period, out of which 25.3% were identified as positive. These results in association with previous data from this area, shows the maintenance of a primary transmission cycle and the occurrence of periodical outbreaks after training activities in local areas of remnant Atlantic rain forest.

  1. Estudo clínico randomizado comparando antimoniato de meglumina, pentamidina e anfotericina B para o tratamento da leishmaniose cutânea ocasionada por Leishmania guyanensis A randomized clinical trial comparing meglumine antimoniate, pentamidine and amphotericin B for the treatment of cutaneous leishmaniasis by Leishmania guyanensis

    OpenAIRE

    Leandro Ourives Neves; Anette Chrusciak Talhari; Ellen Priscilla Nunes Gadelha; Roberto Moreira da Silva Júnior; Jorge Augusto de Oliveira Guerra; Luiz Carlos de Lima Ferreira; Sinésio Talhari

    2011-01-01

    FUNDAMENTOS: O tratamento da leishmaniose tegumentar americana (LTA) ainda constitui desafio, pois a maioria dos medicamentos é injetável e têm-se poucos ensaios clínicos randomizados comparando a eficácia das drogas. Além disso, é provável que as espécies de Leishmania tenham influência nas respostas terapêuticas. OBJETIVOS: Avaliar e comparar a eficácia e a segurança dos esquemas de tratamento na LTA, ocasionada por Leishmania (Viannia) guyanensis. MÉTODOS: 185 pacientes foram...

  2. Potential utility of hyperbaric oxygen therapy and propolis in enhancing the leishmanicidal activity of glucantime / A utilidade da terapia de oxigenação hiperbárica e própolis em potencializar a atividade leishmanicida do glucantime

    Scientific Electronic Library Online (English)

    Diana Copi, Ayres; Thiago Antonio, Fedele; Maria Cristina, Marcucci; Selma, Giorgio.

    2011-12-01

    Full Text Available Nesse trabalho foi avaliada a eficácia da terapia da oxigenação hiperbárica (HBO), aplicada em combinação ou não com o tratamento com glucantime, durante a infecção com Leishmania amazonensis. O efeito de gel da própolis vermelha de origem brasileira (propaina) aplicado em combinação ou não com o tr [...] atamento com glucantime, também foi avaliado durante infecção com esse parasita. A inibição da infecção de macrófagos tratados com glucantime em combinação com HBO foi maior que a de macrófagos tratados apenas com glucantime ou HBO. A linhagem murina susceptível, BALB/c, infectada no dorso com L. amazonensis, tratada com glucantime e exposta a HBO, mostrou durante o curso da doença, fases em que as lesões eram menores do que a de camundongos apenas tratados com glucantime; observou-se revascularização da pele da lesão e baixa produção de interferon-gama em células de linfonodos desses animais. O tratamento com propaina não foi eficiente na cura das lesões, apesar de lesões menos exsudativas serem observadas em animais tratados com propaina ou propaina combinada ao tratamento com glucantime. Os resultados demonstram que tanto HBO como a própolis vermelha em combinação com glucantime, são promissoras no tratamento da leishmaniose cutânea. Novos estudos devem ser realizados para avaliar tratamentos e outros protocolos em diferentes modelos murinos da leishmaniose Abstract in english In this study we investigated the efficacy of hyperbaric oxygen (HBO) therapy, alone or combined with the pentavalent antimonial glucantime on Leishmania amazonensis infection. In parallel, the effect of Brazilian red propolis gel (propain) alone or combined with glucantime on L. amazonensis infecti [...] on was evaluated. The inhibition of the infection in macrophages treated with glucantime in combination with HBO exposition was greater than that of macrophages treated with glucantime alone or HBO alone. The susceptible mouse strain BALB/c infected in the shaved rump with L. amazonensis treated with glucantime and exposed to HBO showed: time points in the course of the disease in which lesions were smaller than those of mice treated with glucantime alone and revascularization of the skin in the lesion site; interferon-gamma (IFN-g) levels were not elevated in lymph node cells from these animals. Propain alone was not efficient against lesions, although less exudative lesions were observed in animals treated with propain alone or combined with glucantime. These results reveal the potential value of HBO and red propolis in combination with glucantime for treating cutaneous leishmaniasis and encourage further studies on the effect of more aggressive HBO, propolis and glucantime therapies on different mouse models of leishmaniasis.

  3. The in vitro leishmanicidal activity of hexadecylphosphocholine (miltefosine) against four medically relevant Leishmania species of Brazil

    Scientific Electronic Library Online (English)

    Eliane de, Morais-Teixeira; Quesia Souza, Damasceno; Mariana Kolos, Galuppo; Alvaro José, Romanha; Ana, Rabello.

    2011-06-01

    Full Text Available The in vitro leishmanicidal activity of miltefosine® (Zentaris GmbH) was assessed against four medically relevant Leishmania species of Brazil: Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis, Leishmania (Viannia) guyanensis and Leishmania (Leishmania) chagasi. The activity of [...] miltefosine against these New World species was compared to its activity against the Old World strain, Leishmania (Leishmania) donovani, which is known to be sensitive to the effects of miltefosine. The IC50 and IC90 results suggested the New World species harboured similar in vitro susceptibilities to miltefosine; however, miltefosine was approximately 20 times more active against the Old World L. (L.) donovani than against the New World L. (L.) chagasi species. The selectivity index varied from 17.2-28.9 for the New World Leishmania species and up to 420.0 for L. (L.) donovani. The differences in susceptibility to miltefosine suggest that future clinical trials with this drug should include a laboratory pre-evaluation and a dose-defining step.

  4. BODY WEIGHT AS A DETERMINANT OF CLINICAL EVOLUTION IN HAMSTERS (Mesocricetus auratus) INFECTED WITH Leishmania (Viannia) panamensis / Peso como determinante da evolução clínica em hamsters (Mesocricetus auratus) infectados com Leishmania (Viannia) panamensis

    Scientific Electronic Library Online (English)

    Angela Maria, Gomez-Galindo; Lucy Gabriela, Delgado-Murcia.

    2013-09-01

    Full Text Available RESUMO O resultado clínico da infecção por espécies de Leishmania do subgênero Viannia no modelo de hamster (Mesocricetus auratus) tem se mostrado diferente, dependendo do protocolo experimental. O peso corporal tem sido um importante determinante da evolução clínica da infecção em hamsters com lei [...] shmaniose visceral, mas sua importância como parâmetro clínico em hamsters com leishmaniose cutânea não é conhecido. Neste estudo, a evolução clínica da infecção com L. (V) panamensis foi avaliada em jovens e adultos hamsters machos durante 11 semanas, comparando os parâmetros clínicos tais como a atitude, a temperatura, a frequência respiratória, a aparência das fezes, e o peso corporal entre infectado e grupos não infectados. Os resultados mostraram que o peso corporal diminuiu em hamsters adultos após infecção por L. (V) panamensis. Esta observação suporta a utilização do peso corporal, como um parâmetro adicional para definir a administração ou o tratamento de leishmaniose cutânea em hamsters adultos infectados usados como modelo animal experimental para a leishmaniose. Abstract in english SUMMARY The clinical outcome of infection with Leishmania species of the subgenus Viannia in hamster model (Mesocricetus auratus) has shown to be different depending on experimental protocol. Body weight has been a relevant determinant of the clinical outcome of the infection in hamsters with visce [...] ral leishmaniasis but its importance as a clinical parameter in hamsters with cutaneous leishmaniasis is not known. In this study, the clinical evolution of infection with L. (V) panamensis was evaluated in juvenile and adult male hamsters during 11 weeks by comparing clinical parameters such as attitude, temperature, respiratory rate, appearance of the stool, and body weight between infected and non-infected groups. Results showed that body weight decreased in adult hamsters after infection by L. (V) panamensis; this observation supports the use of body weight as an additional parameter to define the management or treatment of cutaneous leishmaniasis in infected adult hamsters used as an animal experimental model for leishmaniasis.

  5. Analysis of the specificity of human antibodies to antigens of Leishmania braziliensis braziliensis / Análise da especificidade de anticorpos humanos a antígenos de Leishmania braziliensis braziliensis

    Scientific Electronic Library Online (English)

    Aoi, Masuda; Sueli Fátima do, Nascimento; Carmem Silvia, Guerra; Gláucia da Silva, Paranhos; Antonio Walter, Ferreira.

    1989-08-01

    Full Text Available A antigenicidade de promastigotas de Leishmania braziliensis braziliensis tratadas com desoxicolato de sódio 1% tampão TrisHCl 10 mM pH 8.2 foi determinada por immunoblot usando soros de pacientes com leishmaniose cutânea e mucocutânea, leishmaniose visceral, esquistossomose, malária e doença de Cha [...] gas. Os soros de pacientes com leishmaniose cutânea e mucocutânea apresentaram reação positiva com uma banda de 60 kD. Não se observou reatividade para esta fração em soros de pacientes com outras doenças parasitárias acima mencionadas, indicando que esta pode ser utilizada no sorodiagnóstico de leishmaniose tegumental. Abstract in english The antigenicity of promastigotes of Leishmania braziliensis braziliensis (L. b.braziliensis) treated with 1% sodium desoxycholate in 10 mM Tris-Hcl pH 8.2 was analysed by immunoblot using as probes sera from American cutaneous leishmaniasis (ACL), American visceral leishmaniasis (AVL), schistosomia [...] sis, malaria and Chagas' disease. The ACL sera reacted constantly with a 60 kD band. No reactivity to this protein was observed with sera from the other diseases above mentioned indicating that the 60 kD protein may be used in serodiagnosis for ACL.

  6. Analysis of the specificity of human antibodies to antigens of Leishmania braziliensis braziliensis Análise da especificidade de anticorpos humanos a antígenos de Leishmania braziliensis braziliensis

    Directory of Open Access Journals (Sweden)

    Aoi Masuda

    1989-08-01

    Full Text Available The antigenicity of promastigotes of Leishmania braziliensis braziliensis (L. b.braziliensis treated with 1% sodium desoxycholate in 10 mM Tris-Hcl pH 8.2 was analysed by immunoblot using as probes sera from American cutaneous leishmaniasis (ACL, American visceral leishmaniasis (AVL, schistosomiasis, malaria and Chagas' disease. The ACL sera reacted constantly with a 60 kD band. No reactivity to this protein was observed with sera from the other diseases above mentioned indicating that the 60 kD protein may be used in serodiagnosis for ACL.A antigenicidade de promastigotas de Leishmania braziliensis braziliensis tratadas com desoxicolato de sódio 1% tampão TrisHCl 10 mM pH 8.2 foi determinada por immunoblot usando soros de pacientes com leishmaniose cutânea e mucocutânea, leishmaniose visceral, esquistossomose, malária e doença de Chagas. Os soros de pacientes com leishmaniose cutânea e mucocutânea apresentaram reação positiva com uma banda de 60 kD. Não se observou reatividade para esta fração em soros de pacientes com outras doenças parasitárias acima mencionadas, indicando que esta pode ser utilizada no sorodiagnóstico de leishmaniose tegumental.

  7. Estado atual da leishmaniose cutânea difusa (LCD) no Estado do Maranhão: II. aspectos epidemiológicos, clínico-evolutivos

    Scientific Electronic Library Online (English)

    Jackson Maurício Lopes, Costa; Ana Cristina Rodrigues, Saldanha; Ana Carla de Melo e, Silva; Artur, Serra Neto; Clovis Eduardo Santos, Galvão; Conceição de Maria Pedroso e, Silva; Antonio Rafael da, Silva.

    1992-06-01

    Full Text Available Os Autores fazem um estudo retrospectivo e prospectivo de 6 pacientes portadores de leishmaniose cutânea difusa, observados no Estado do Maranhão a partir de 1974. Os casos abordados são oriundos de diversas regiões do estado, observando-se em todos eles o envolvimento da leishmania (Leishmania) ama [...] zonensis, sendo que 5 (84%) dos pacientes apresentaram início de doença na 1ª década de vida. Em todos os pacientes envolvidos no estudo, houve relato de lesão inicial nodular única, que, posteriormente, em período variável de tempo, disseminou-se adquirindo outros aspectos. Evolutivamente apresentaram múltiplas lesões nodulares e ulceradas, intradermorreação de Montenegro(-) e refratariedade aos esquemas terapêuticos utilizados até ao presente momento. Abstract in english The authors describe a retrospective and prospective study of 6 patients with diffuse cutaneous leishmaniasis observed in the State of Maranhão, since 1974. The patients comefromdifferentruralregions of the state and in all of them Leishmania (Leishmania) amazonensis was the cause five of the patien [...] ts initiated their disease in the first decade of life. All the patients first had a solitary, nodular lesion, that after a variable period of time, disseminated and acquired other aspects. Sequentially the patients presented multiple nodular and ulcerative lesions, negative leishmania skin-lests and a refractory response to the therapeutic schedules used up to the present.

  8. Leishmania (Viannia) braziliensis is the main species causing cutaneous leishmaniasis in the Federal District of Brazil

    Scientific Electronic Library Online (English)

    GM, Santos; SA, Kückelhaus; AM, Roselino; WK, Chaer; RNR, Sampaio.

    Full Text Available The first autochthonous case of American cutaneous leishmaniasis was reported in the Federal District in 1980, and the species involved in this type of leishmaniasis was unknown. This study aimed to identify the species that causes the disease in the Federal District and to investigate its clinical [...] and epidemiological aspects. Between 2000 and 2007, 71 autochthonous cases of leishmaniasis were reported in the Federal District. Leishmania species were identified by means of direct immunofluorescence reactions using monoclonal antibodies and restriction fragment length polymorphism. The species of 40 (56.33%) out of 71 samples were identified. Thirty-six (90%) were identified as Leishmania (Viannia) braziliensis and four (10%) were identified as Leishmania (Leishmania) amazonensis. In this area, the disease had clinical and epidemiological characteristics similar to those found in other Brazilian regions.

  9. Leishmania infection in a population of dogs: an epidemiological investigation relating to visceral leishmaniasis control / Infecção por Leishmania em uma população de cães: uma investigação epidemiológica relacionada ao controle da leishmaniose visceral

    Scientific Electronic Library Online (English)

    Klauber Menezes, Penaforte; Vinicius Silva, Belo; Rafael Goncalves, Teixeira-Neto; Renata Aparecida Nascimento, Ribeiro; Robson Bruniera de, Oliveira; Dante Alighieri, Schettini; Eduardo Sergio da, Silva.

    2013-12-01

    Full Text Available A identificação dos fatores associados à infecção por Leishmania em cães é essencial para o direcionamento das ações de controle da leishmaniose visceral. Desta forma, o presente estudo analisa alguns destes fatores em uma população de cães, bem como as limitações das estratégias de controle executa [...] das em um município brasileiro. Por meio de modelos de regressão logística, analisou-se a associação entre as variáveis de exposição e a ocorrência de infecção. As ações de controle da doença foram analisadas qualitativamente. Dos 755 animais avaliados por meio de sorologia, 13,6% (103/755) foram soro-reagentes. Destes, 23,3% (24/103) eram assintomáticos e 76,7% (79/103) apresentaram pelo menos um sinal clínico possivelmente associado com a leishmaniose visceral. Com associações fracas, cães de raça pura, de pelo curto, com mais de cinco anos, machos e de grande porte foram mais propensos à infecção. As duas últimas variáveis compuseram o modelo final de regressão, sendo significativa a associação com o tamanho do cão. As estratégias de controle desenvolvidas apresentaram limitações e um número elevado de cães sorologicamente negativos foi submetido a eutanásia. Os dados apresentados contribuem para um melhor entendimento da dinâmica da infecção na leishmaniose visceral canina e indicam que ações visando a adequada execução do programa de controle da doença em áreas endêmicas brasileiras devem ser priorizadas. Abstract in english Identification of factors associated with Leishmania infection in dogs is essential for targeting visceral leishmaniasis control actions. Thus, the present study analyzed some of these factors in a population of dogs in a Brazilian municipality, along with the limitations of control strategies imple [...] mented there. The association between the exposure variables and occurrences of infection was analyzed through logistic regression models. The disease control interventions were treated qualitatively. Out of the 755 animals examined, 13.6% (103/755) were seropositive. Of these, 23.3% (24/103) were asymptomatic and 76.7% (79/103) presented at least one clinical sign possibly associated with visceral leishmaniasis. With weak associations, purebred, shorthaired, over 5 years of age, male and large dogs were more prone to infection. The latter two variables formed the final regression model and the association with dog size was statistically significant. The control strategies developed presented limitations and a great number of seronegative dogs was culled. The data presented contribute towards better understanding of the dynamics of infection in canine visceral leishmaniasis and indicate that actions aimed towards adequate implementation of Visceral Leishmaniasis control program in Brazilian endemic areas should be prioritized.

  10. Mefloquina no tratamento da leishmaniose cutânea em uma área endêmica de Leishmania (Viannia) braziliensis / Efficacy of mefloquine in the treatment of skin leishmaniasis in an endemic area of Leishmania (Viannia) braziliensis

    Scientific Electronic Library Online (English)

    Victor Alberto, Laguna-Torres; Carlos A.C., Silva; Dalmo, Correia; Edgard M., Carvalho; Albino V., Magalhães; Vanize de Oliveira, Macêdo.

    1999-10-01

    Full Text Available O objetivo deste trabalho foi avaliar a eficácia da mefloquina numa região endêmica de leishmaniose cutânea por Leishmania (Viannia) braziliensis, considerando que esta droga de administração oral, eficaz no tratamento da malária, com meia vida prolongada e efeitos colaterais pouco freqüentes poderi [...] a ser menos tóxica e de mais fácil administração, quando comparada com os antimoniais pentavalentes. Em Corte de Pedra, no litoral sul do Estado da Bahia, foram tratados, aleatoriamente, dez pacientes portadores de lesões leishmanióticas, subdivididos em dois grupos. O primeiro grupo recebeu mefloquina pela via oral, dose de 250mg/dia, durante seis dias, repetindo-se o mesmo esquema após intervalo de três semanas. O segundo grupo recebeu antimoniato de meglumina (Glucantime®) diariamente, pela via endovenosa, na dose de 20mg/kg por 20 dias. Do grupo da mefloquina só um paciente apresentou cicatrização depois do segundo ciclo. Um desses, com quatro lesões apresentou nova lesão durante o primeiro ciclo de tratamento. A evolução dos outros três foi lenta sendo que em nove semanas nenhum deles tinha cicatrizado as úlceras que permaneciam com grande infiltração e sinais evidentes de atividade. O grupo tratado com Glucantime® apresentou evidente melhora. Abstract in english The aim of this study was to evaluate the efficacy of mefloquine in the treatment of skin leishmaniasis in patients infected with Leishmania (Viannia) braziliensis at an endemic region. Mefloquine is an oral drug effective against malaria with a prolonged half-life, less toxicity and easier administ [...] ration than pentavalent antimonials. At Corte de Pedra in the Southern litoral of Bahia State, two randomized groups of ten patients with leishmaniasis were treated. The first group was treated with oral mefloquine, 250mg per day in a single dose for six days and repeated three weeks later. The second group received meglumine antimoniate (Glucantime®), 20mg/kg daily administered intravenously for 20 days. Only one patient in the group treated with mefloquine showed evidence of clinical success. During treatment, one patient with four lesions developed a new lesion. The other three patients with clinical leismaniasis did not show evidence of clinical success after nine weeks of treatment. The group treated with Glucantime® showed evident clinical improvement of the skin lesions.

  11. Monoclonal antibody affinity purification of a Leishmania membrane glycoprotein and its inhibition of leishmania-macrophage binding.

    OpenAIRE

    Chang, C. S.; Chang, K P

    1986-01-01

    Specific monoclonal antibody coupled to Affi-Gel 10 was used to purify a major membrane glycoprotein of Leishmania mexicana amazonensis, one of a group of parasitic protozoa that specifically infect mammalian macrophages. Immobilized antigen was eluted at a 34% efficiency with buffers at either pH 2.5 or 11 or with MgCl2, but only the antigen eluted under basic conditions could be readsorbed to the immunobeads. Sephacryl S-300 gel filtration of the purified antigen gave a single peak of prote...

  12. Action of Bothrops moojeni venom and its L-amino acid oxidase fraction, treated with 60Co gamma rays, in Leishmania spp

    International Nuclear Information System (INIS)

    Bothrops moojeni venom showed an anti leishmania activity in vitro, as determined by a cell viability assay using the reduction of MTT. After venom purification, by chromatography techniques, the fractions with anti leishmania and L-amino acid oxidase activities, eluted in the same positions. The molecular weight of the enzyme was estimated to be 140 kDa by molecular exclusion chromatography, and 69 kDa, by SDS-PAGE, migrating as a single band, with an isoelectric point of 4.8 as determined by isoelectric focusing. The purified LAO from B. moojeni venom, 135-fold more active than crude venom, showed homo dimeric constitution, and was active against Leishmania spp from the New World, with an effective concentration against L(L). amazonensis of 1.80 ?g/ml (EC50), L.(V.) panamensis (0.78 |?g/ml) and L.(L.) chagasi (0.63 (?g/ml). Ultrastructural studies of promastigotes affected by LAO demonstrated cell death, with edema in several organelles such as mitochondria and nuclear membrane, before cell disruption and necrosis. The action of LAO was demonstrated to be hydrogen peroxide-dependent. Studies with LLCMK-2 cells, treated with LAO, showed a toxic effect, with an EC50 of 11|?g/ml. Irradiation of LAO with 60Co gamma rays, did not affect its whole oxidative activity, neither detoxified the enzyme. Amastigotes treated with LAO were not affected by its hydrogen peroxide, otherwise, the exogenous product, killed amastigotes with an EC50 of 0.67mM. These data could be of help in the development of alternative therapeutic approaches to the treatment of leishmaniasis. (author)

  13. Behavior of Leishmania major metacyclic promastigotes during the course of infection and immune response development in resistant versus susceptible hosts Comportamento de promastigoteas metacíclicos de Leishmania major durante o curso da infecção e da resposta imune em hospedeiros resistentes versus suscetíveis

    Directory of Open Access Journals (Sweden)

    Regina Coeli Cunha Dórea

    2003-11-01

    Full Text Available Little is known on the epitopes derived from metacyclic promastigotes of Leishmania that are important on the regulation or destruction of the parasite, as targets of immune attack in the vertebrate host. In this study we investigated an alternative method to obtain metacyclic promasigotes of Leishmania major, as evaluated by the course of infection and delayed-type hipersensitivity (DTH in resistant versus susceptible inbred mice. Non-infective (procyclic promastigotes of L. major recently transformed from tissue amastigotes were attached to a negatively charged glass-wool column, whereas metacyclic promastigotes were not bound to columns and could be easily recovered. Optimal chromatography conditions were validated through statistical analyses. Parasite average yield from glass wool columns and promastigote viability were estimated by light microscopy. Metacyclic promastigotes yielded 43.5% to 57.5%. Different patterns of cutaneous lesions were obtained in BALB/c (susceptible and C57BL/6 (resistant mice, the former with highly infective lesions induced by metacyclic promastigotes. DTH responses proved to be higher in groups of C57BL/6 mice which were infected with metacyclic promastigotes. These results indicate that the new method could be integrated with the investigation of metacyclogenesis of Leishmania in vivo.Pouco se conhece sobre os epítopos derivados de promastigotas metacíclicos de Leishmania que são importantes para a regulação ou destruição do parasita, como alvos de ação imunológica no hospedeiro vertebrado. Neste estudo, nós investigamos um método alternativo para obter promastigotas metacíclicos de Leishmania major, pela avaliação do curso da infecção e reação de hipersensibilidade do tipo retardado (HTR em hospedeiros resistentes e susceptíveis. Promastigotas não-infectantes (procíclicos de L. major, recentemente isolados de amastigotas, foram selecionados pela adesão a colunas de lã de vidro negativamente carregadas, enquanto que promastigotas metacíclicos não se aderem à coluna e podem ser recuperados com facilidade. Condições ótimas de cromatografia foram validadas por análise estatística. O rendimento médio de parasitas obtidos após separação em colunas de lã de vidro e a viabilidade dos promastigotas foram estimados por microscopia óptica. Os promastigotas metacíclicos tiveram um rendimento médio de 43,5% a 57,5%. Camundongos BALB/c (susceptíveis e camundongos C57BL/6 (resistentes apresentaram padrões distintos de lesões cutâneas, os primeiros com lesões mais agressivas, induzidas por promastigotas metacíclicos. As respostas à reação de HTR foram maiores nos grupos de camundongos C57BL/6, submetidos à infecção com promastigotas metacíclicos. Estes resultados indicam que o novo método poderia ser integrado aos protocolos existentes para estudar a metaciclogênese de parasitas do gênero Leishmania in vivo.

  14. Clavulina amazonensis, an Amazonian fungus discovered in the Atlantic Forest / Clavulina amazonensis, un hongo amazónico descubierto en la Mata Atlántica

    Scientific Electronic Library Online (English)

    Felipe, Wartchow.

    2012-06-01

    Full Text Available Se reporta Clavulina amazonensis por primera vez para la Selva Atlántica del Nordeste de Brasil con base en material de herbario. La especie se caracteriza por basidiosporas subglobosas pequeñas, basidios con dos a tries esterigmas cornudos y contexto con hifas marrón anaranjadas. Se presenta descri [...] pción, ilustraciones y una discusión sobre su distribución. Abstract in english Clavulina amazonensis is reported for the first time in the Atlantic Forest of Northeastern Brazil from herbarium material. C. amazonensis is characterized by branched basidiomes with, hymenium, small subglobose basidiospores, frequency of three sterigmata per basidia and context bearing orange-brow [...] n hyphae. Description, drawings, and discussion on its biogeography are provided here.

  15. Canine visceral leishmaniasis due to Leishmania (L.) infantum chagasi in Amazonian Brazil: comparison of the parasite density from the skin, lymph node and visceral tissues between symptomatic and asymptomatic, seropositive dogs / Leishmaniose visceral canina causada por Leishmania (L.) infantum chagasi na Amazônia brasileira: comparação da densidade parasitária da pele, linfonodo e vísceras entre cães soropositivos, sintomáticos e assintomáticos

    Scientific Electronic Library Online (English)

    Luciana Vieira R., Lima; Liliane Almeida, Carneiro; Marliane Batista, Campos; Eujênia Janis, Chagas; Márcia D., Laurenti; Carlos E.P., Corbett; Ralph, Lainson; Fernando Tobias, Silveira.

    2010-10-01

    Full Text Available A leishmaniose visceral canina (LVC) é reconhecida pelas características clínicas da doença e é altamente letal. A infecção, entretanto, pode ser totalmente assintomática em alguns cães soropositivos, o que tem levantado questão polêmica sobre a possibilidade desses animais, serem ou não uma fonte i [...] mportante da infecção para o flebotomíneo, Lutzomyia longipalpis, o principal vetor da leishmaniose visceral americana (LVA). Neste estudo foram examinados 51 cães com LVC aguda, provenientes de área endêmica de LVA no Estado do Pará, Brasil, e a carga parasitária, formas amastigotas de Leishmania (L.) infantum chagasi, na pele, linfonodo poplíteo e vísceras (fígado e baço) foi comparada com a de nove cães assintomáticos soropositivos (IFAT-IgG). Fragmentos de biópsia desses tecidos obtidos post-mortem foram processados para análise através de imunohistoquímica, usando um anticorpo policlonal contra Leishmania sp. Os testes do Qui-quadrado (X²) e Mann Whitney foram usados para avaliar as médias da densidade de macrófagos infectados (p 0,05) na densidade de macrófagos infectados da pele (10,7/mm² x 15,5/mm²) e do linfonodo (6,3/mm² x 8,3/mm²) entre cães assintomáticos e sintomáticos. Entretanto, a densidade de macrófagos infectados da víscera de cães sintomáticos (5,3/mm²) foi maior (p Abstract in english Canine visceral leishmaniasis (CVL) is recognizable by characteristic signs of disease and is highly lethal. The infection, however, may be quite inapparent in some seropositive dogs, and this has raised the polemic question as to whether or not such animals can be a source of infection for Lutzomyi [...] a longipalpis, the vector of American visceral leishmaniasis (AVL). In this study we have examined 51 dogs with acute CVL from an AVL area in Pará State, northern Brazil, and compared the parasite density, amastigotes of Leishmania (L.) infantum chagasi, in the skin, lymph node and viscera of symptomatic with that of nine asymptomatic but seropositive dogs (IFAT-IgG). Post-mortem biopsy fragments of these tissues were processed by immunohistochemistry, using a polyclonal antibody against Leishmania sp. The X² and Mann Whitney tests were used to evaluate the means of infected macrophage density (p 0.05) in the skin (10.7/mm² x 15.5/mm²) and lymph node (6.3/mm² x 8.3/mm²), between asymptomatic and symptomatic dogs, respectively. It was higher (p

  16. Immunoperoxidase technique using an anti-Leishmania (L.) chagasi hyperimmune serum in the diagnosis of culture-confirmed American tegumentary leishmaniasis / Técnica da imunoperoxidase utilizando um soro hiperimune anti-Leishmania (L.) chagasi no diagnóstico da leishmaniose tegumentar americana confirmada por cultura

    Scientific Electronic Library Online (English)

    Leonardo P., Quintella; Tullia, Cuzzi; Maria de F., Madeira; Thais, Okamoto; Armando de O., Schubach.

    2009-04-01

    Full Text Available O presente estudo relata a produção do soro policlonal de coelho anti-Leishmania (L.) chagasi, a padronização da técnica de imunohistoquímica (IHQ) e sua aplicação em lesões de leishmaniose cutânea (LC) diagnosticadas por isolamento de Leishmania sp. em cultura. Foram examinados 30 fragmentos de les [...] ões ativas de LC e 10 fragmentos de lesões de etiologia fúngica, utilizados como grupo controle. A IHQ mostrou-se mais sensível na detecção de amastigotas que a coloração em hematoxilina-eosina (HE), sendo positiva em 24 fragmentos de LC (80%) e ao passo que a HE foi positiva em 16 (53%) (p = 0,028). A IHQ também marcou diferentes espécies de fungos causadoras de micoses cutâneas. Adicionalmente, verificou-se positividade no citoplasma de células mononucleares e células endoteliais. Entretanto, esse achado esteve presente no grupo controle. Conclui-se que o método de IHQ apresentou boa sensibilidade na detecção de formas amastigotas. Abstract in english The present study reports the production of the rabbit anti-Leishmania (L.) chagasi hyperimmune serum, the standardization of the immunohistochemistry (IHC) technique and the evaluation of its employment in cutaneous leishmaniasis (CL) lesions diagnosed by Leishmania sp. culture isolation. Thirty fr [...] agments of active CL lesions were examined as well as 10 fragments of cutaneous mycosis lesions as control group. IHC proved more sensitive in detecting amastigotes than conventional hematoxylin-eosin (HE) stained slides: the former was positive in 24 (80%) biopsies whereas the latter, in 16 (53%) (p = 0.028). The reaction stained different fungus species causing cutaneous mycosis. Besides, positive reaction was noticed in mononuclear and endothelial cells. Nevertheless, this finding was present in the control group biopsies. It is concluded that IHC showed good sensitivity in detecting amastigotes.

  17. Comparative analysis of the geographic distribution of the histopathological spectrum and Leishmania species of American cutaneous leishmaniasis in Brazil Análise comparativa da distribuição geográfica do espectro histopatológico e espécies de Leishmania da leishmaniose tegumentar americana no Brasil

    OpenAIRE

    Linton Wallis Figueiredo Souza; Simone Vilas Trancoso Souza; Ana Cristina Carvalho Botelho

    2012-01-01

    BACKGROUND: Knowledge of the relationship between specific geographical differences and histopathology of the American cutaneous leishmaniasis is limited because host-parasite interactions in space and time are complex. OBJECTIVE: To describe the geographic analysis of the histopathological pattern of localized American cutaneous leishmaniasis and the relationship with Leishmania species. METHODS: A cross-sectional, descriptive and analytical study of a sample consisting of 55 patients of mun...

  18. Polymerase chain reaction and real-time PCR for diagnosing of Leishmania infantum chagasi in dogs / Reação em Cadeia da Polimerase e PCR em tempo real para diagnóstico de Leishmania infantum chagasi em cães

    Scientific Electronic Library Online (English)

    Rafael Antonio do Nascimento, Ramos; Carlos Alberto do Nascimento, Ramos; Márcia Mariza Gomes, Jusi; Flábio Ribeiro de, Araújo; Rosangela Zacarias, Machado; Maria Aparecida da Glória, Faustino; Leucio Câmara, Alves.

    2012-09-01

    Full Text Available A importância do cão como reservatório de L. infantum chagasi no meio urbano tem estimulado a realização de inúmeros trabalhos de avaliação de técnicas de diagnóstico, uma vez que este procedimento, quando realizado corretamente, torna-se um importante passo na prevenção da doença em humanos. Dentre [...] os métodos de diagnóstico, as técnicas moleculares têm adquirido destaque. Objetivou-se neste trabalho verificar o desempenho da Reação em Cadeia da Polimerase (PCR) e da PCR em tempo real (qPCR) para diagnóstico da Leishmaniose Visceral Canina (LVC) utilizando diferentes amostras biológicas. Para tanto foram utilizados 35 cães provenientes de uma área endêmica para LVC, onde foram utilizados para o diagnóstico molecular, aspirado de medula óssea, fragmentos de linfonodo e baço. Neste estudo a qPCR foi capaz de detectar um maior número de animais positivos quando comparada com a PCR. Já entre as diferentes amostras biológicas utilizadas não foi observada diferença significativa na detecção de DNA de L. infantumchagasi por meio da PCR e qPCR. Mesmo assim, considerando a facilidade de obtenção, o linfonodo pode ser considerada como a melhor amostra para diagnóstico molecular da infecção por L. infantum chagasi. Abstract in english The importance of dogs as a reservoir for Leishmania infantumchagasi in urban environments has stimulated numerous studies assessing diagnostic techniques. When performed properly, such procedures are an important step in preventing leishmaniasis in humans. Molecular methods have become prominent fo [...] r this purpose. The aim of the present study was to determine the performance of the polymerase chain reaction (PCR) and real-time PCR (qPCR) for diagnosing of canine visceral leishmaniasis (CVL) using different biological samples. For this, 35 dogs from an area endemic for CVL were used. Bone marrow aspirate and lymph node and spleen fragments from these dogs were used for the molecular diagnosis. In the present study, qPCR was able to detect a greater number of positive animals than seen with PCR. Among the different biological samples used, there was no significant difference in L. infantumchagasi DNA detection between PCR and qPCR. However, considering that lymph nodes are easy to acquire, these can be considered to be the best samples for making molecular diagnoses of L. infantum chagasi infection.

  19. The efficacy of 2-nitrovinylfuran derivatives against Leishmania in vitro and in vivo

    Scientific Electronic Library Online (English)

    Sergio, Sifontes-Rodríguez; Lianet, Monzote-Fidalgo; Nilo, Castañedo-Cancio; Ana Margarita, Montalvo-Álvarez; Yamilé, López-Hernández; Niurka Mollineda, Diogo; Juan Francisco, Infante-Bourzac; Oliver, Pérez-Martín; Alfredo, Meneses-Marcel; José Antonio Escario, García-Trevijano; Miguel Ángel, Cabrera-Pérez.

    2015-04-01

    Full Text Available Despite recent advances in the treatment of some forms of leishmaniasis, the available drugs are still far from ideal due to inefficacy, parasite resistance, toxicity and cost. The wide-spectrum antimicrobial activity of 2-nitrovinylfuran compounds has been described, as has their activity against T [...] richomonas vaginalis and other protozoa. Thus, the aim of this study was to test the antileishmanial activities of six 2-nitrovinylfurans in vitro and in a murine model of leishmaniasis. Minimum parasiticide concentration (MPC) and 50% inhibitory concentration (IC50) values for these compounds against the promastigotes of Leishmania amazonensis, Leishmania infantum and Leishmania braziliensis were determined, as were the efficacies of two selected compounds in an experimental model of cutaneous leishmaniasis (CL) caused by L. amazonensis in BALB/c mice. All of the compounds were active against the promastigotes of the three Leishmania species tested. IC50 and MPC values were in the ranges of 0.8-4.7 µM and 1.7-32 µM, respectively. The compounds 2-bromo-5-(2-bromo-2-nitrovinyl)-furan (furvina) and 2-bromo-5-(2-methyl-2-nitrovinyl)-furan (UC245) also reduced lesion growth in vivo at a magnitude comparable to or higher than that achieved by amphotericin B treatment. The results demonstrate the potential of this class of compounds as antileishmanial agents and support the clinical testing of Dermofural(r) (a furvina-containing antifungal ointment) for the treatment of CL.

  20. The efficacy of 2-nitrovinylfuran derivatives against Leishmania in vitro and in vivo

    Scientific Electronic Library Online (English)

    Sergio, Sifontes-Rodríguez; Lianet, Monzote-Fidalgo; Nilo, Castañedo-Cancio; Ana Margarita, Montalvo-Álvarez; Yamilé, López-Hernández; Niurka Mollineda, Diogo; Juan Francisco, Infante-Bourzac; Oliver, Pérez-Martín; Alfredo, Meneses-Marcel; José Antonio Escario, García-Trevijano; Miguel Ángel, Cabrera-Pérez.

    Full Text Available Despite recent advances in the treatment of some forms of leishmaniasis, the available drugs are still far from ideal due to inefficacy, parasite resistance, toxicity and cost. The wide-spectrum antimicrobial activity of 2-nitrovinylfuran compounds has been described, as has their activity against T [...] richomonas vaginalis and other protozoa. Thus, the aim of this study was to test the antileishmanial activities of six 2-nitrovinylfurans in vitro and in a murine model of leishmaniasis. Minimum parasiticide concentration (MPC) and 50% inhibitory concentration (IC50) values for these compounds against the promastigotes of Leishmania amazonensis, Leishmania infantum and Leishmania braziliensis were determined, as were the efficacies of two selected compounds in an experimental model of cutaneous leishmaniasis (CL) caused by L. amazonensis in BALB/c mice. All of the compounds were active against the promastigotes of the three Leishmania species tested. IC50 and MPC values were in the ranges of 0.8-4.7 µM and 1.7-32 µM, respectively. The compounds 2-bromo-5-(2-bromo-2-nitrovinyl)-furan (furvina) and 2-bromo-5-(2-methyl-2-nitrovinyl)-furan (UC245) also reduced lesion growth in vivo at a magnitude comparable to or higher than that achieved by amphotericin B treatment. The results demonstrate the potential of this class of compounds as antileishmanial agents and support the clinical testing of Dermofural(r) (a furvina-containing antifungal ointment) for the treatment of CL.

  1. The efficacy of 2-nitrovinylfuran derivatives against Leishmania in vitro and in vivo

    Science.gov (United States)

    Sifontes-Rodríguez, Sergio; Monzote-Fidalgo, Lianet; Castañedo-Cancio, Nilo; Montalvo-Álvarez, Ana Margarita; López-Hernández, Yamilé; Diogo, Niurka Mollineda; Infante-Bourzac, Juan Francisco; Pérez-Martín, Oliver; Meneses-Marcel, Alfredo; García-Trevijano, José Antonio Escario; Cabrera-Pérez, Miguel Ángel

    2015-01-01

    Despite recent advances in the treatment of some forms of leishmaniasis, the available drugs are still far from ideal due to inefficacy, parasite resistance, toxicity and cost. The wide-spectrum antimicrobial activity of 2-nitrovinylfuran compounds has been described, as has their activity against Trichomonas vaginalis and other protozoa. Thus, the aim of this study was to test the antileishmanial activities of six 2-nitrovinylfurans in vitro and in a murine model of leishmaniasis. Minimum parasiticide concentration (MPC) and 50% inhibitory concentration (IC50) values for these compounds against the promastigotes of Leishmania amazonensis, Leishmania infantum and Leishmania braziliensis were determined, as were the efficacies of two selected compounds in an experimental model of cutaneous leishmaniasis (CL) caused by L. amazonensis in BALB/c mice. All of the compounds were active against the promastigotes of the three Leishmania species tested. IC50 and MPC values were in the ranges of 0.8-4.7 µM and 1.7-32 µM, respectively. The compounds 2-bromo-5-(2-bromo-2-nitrovinyl)-furan (furvina) and 2-bromo-5-(2-methyl-2-nitrovinyl)-furan (UC245) also reduced lesion growth in vivo at a magnitude comparable to or higher than that achieved by amphotericin B treatment. The results demonstrate the potential of this class of compounds as antileishmanial agents and support the clinical testing of Dermofural(r) (a furvina-containing antifungal ointment) for the treatment of CL. PMID:25946239

  2. Terpenes Increase the Lipid Dynamics in the Leishmania Plasma Membrane at Concentrations Similar to Their IC50 Values

    OpenAIRE

    Camargos, Heverton Silva; Moreira, Rodrigo Alves; Mendanha, Sebastia?o Antonio; Fernandes, Kelly Souza; Dorta, Miriam Leandro; Alonso, Antonio

    2014-01-01

    Although many terpenes have shown antitumor, antibacterial, antifungal, and antiparasitic activity, the mechanism of action is not well established. Electron paramagnetic resonance (EPR) spectroscopy of the spin-labeled 5-doxyl stearic acid revealed remarkable fluidity increases in the plasma membrane of terpene-treated Leishmania amazonensis promastigotes. For an antiproliferative activity assay using 5×106 parasites/mL, the sesquiterpene nerolidol and the monoterpenes (+)-limonene, ?-terp...

  3. Identification of Leishmania chagasi from skin in Leishmania/HIV co-infection: a case report Identificação de Leishmania chagasi na pele em co-infecção Leishmania/HIV: relato de caso

    Directory of Open Access Journals (Sweden)

    Marcela Orsini

    2002-06-01

    Full Text Available A case of HIV/Leishmania co-infection presenting both visceral and cutaneous manifestations is reported. Leishmania infection was confirmed by conventional methods (parasitological approach and serology and by PCR. Leishmania chagasi isolated from the skin lesion was characterized by enzyme electrophoresis and by restriction fragment length polymorphism of the internal transcribed spacer of the ribosomal gene.É descrito um caso de co-infecção leishmania/HIV com manifestações cutâneas e visceral. Infecção pela leishmania foi confirmada através de métodos convencionais (parasitológicos e sorológicos e através da PCR. A espécie Leishmania chagasi isolada da pele foi caracterizada por eletroforese enzimática e por polimorfismo de fragmento obtido por enzima de restrição.

  4. Identification of Leishmania chagasi from skin in Leishmania/HIV co-infection: a case report / Identificação de Leishmania chagasi na pele em co-infecção Leishmania/HIV: relato de caso

    Scientific Electronic Library Online (English)

    Marcela, Orsini; Marcelo, Silva; Zélia Maria Profeta da, Luz; Jolandt, Disch; Octávio, Fernandes; Dalton, Moreira; Antonio Carlos Martins, Guedes; Ana, Rabello.

    2002-06-01

    Full Text Available É descrito um caso de co-infecção leishmania/HIV com manifestações cutâneas e visceral. Infecção pela leishmania foi confirmada através de métodos convencionais (parasitológicos e sorológicos) e através da PCR. A espécie Leishmania chagasi isolada da pele foi caracterizada por eletroforese enzimátic [...] a e por polimorfismo de fragmento obtido por enzima de restrição. Abstract in english A case of HIV/Leishmania co-infection presenting both visceral and cutaneous manifestations is reported. Leishmania infection was confirmed by conventional methods (parasitological approach and serology) and by PCR. Leishmania chagasi isolated from the skin lesion was characterized by enzyme electro [...] phoresis and by restriction fragment length polymorphism of the internal transcribed spacer of the ribosomal gene.

  5. Actividad in vitro de la mezcla de alcaloides de Ervatamia coronaria (Jacq) Staff. Apocynaceae sobre amastigotes de Leishmania braziliensis / In vitro activity of the alkaloids mixture of Ervatamia coronaria (Jacq) Staff. Apocynaceae on Leishmania braziliensis amastigotes / Atividade in vitro da mistura de alcalóides de Ervatamia coronaria (Jacq) Staff. Apocynaceae sobre amastigotas de Leishmania braziliensis

    Scientific Electronic Library Online (English)

    Amanda, Moreno Rodríguez; Jorge, Robles Camargo; Felio J., Bello García.

    2008-09-01

    Full Text Available A leishmaniose é considerada uma importante causa de morbidade e mortalidade a nível mundial, principalmente nos países tropicais. As formas cutânea e mucocutânea são causadas, entre outras espécies, por Leishmania braziliensis. Na procura de compostos leishmanicidas de origem natural, foi estudada [...] a atividade da mistura de alcalóides de Ervatamia coronaria (Apocynaceae) contra amastigotas de L. braziliensis em 6 concentrações diferentes (1, 10, 20, 25, 50 e 100 µg/mL). Foram tratados macrófagos de ratos da linha J774, infectados com promastigotas de L. braziliensis, com a mistura de alcalóides 1 hora após-infecção e diariamente por 3 dias sem mudança de meio. As experiências de citotoxicidade foram efetuadas sobre os macrófagos com azul tripam. Todos os cultivos foram feitos de forma triplicada e os grupos de controle não foram submetidos à mistura de alcalóides. Foi obtido que o composto adicionado exerce atividade doses/dependente sobre a parasita. No entanto, as concentrações mais altas (50 e 100 µg/mL), adicionado durante 3 dias, mostraram os maiores índices de infecção, provavelmente devido a diminuição no número de macrófagos, sobre os quais não foi observado efeito tóxico do tratamento durante 24 horas DL50/24h = 233,52 µg/mL. Os resultados dessa pesquisa revelaram uma nova atividade farmacológica de alcalóides da espécie Ervatamia coronaria sobre a forma amastigota de Leishmania braziliensis, com IC50 = 2,6 e 12,4 µg/mL sem mostrar toxicidade sobre a célula hospedeira. Abstract in spanish [...] Abstract in english Leishmaniasis, caused by Leishmania sp., is one of the mean reason of considerable mortality and morbidity throughout the world, especially in the tropics. Cutaneous and mucocutaneous manifestations are caused by Leishmania braziliensis, and the cutaneous form is the most common one in Colombia. In [...] the search for antileishmanial compounds from natural sources, we studied the alkaloids mixture from Ervatamia coronaria against L. braziliensis at six different concentrations (1.0, 10, 20, 25, 50 and 100 µg/mL). Macrophages J774 infected with L. braziliensis were treated with alkaloids one hour, and once a day for three days, after parasitic infection and preserving the same culture medium. Cytotoxicity with trypan blue was undertaken in macrophages J774 by using the same concentrations. Three different cultures samples were carried out. As a control we used medium alone. The alkaloids mix showed a dose/dependent activity on amastigote, but by increasing concentrations from 50 to 100 µg/mL for three days, we saw a high index of infection, probably caused by cellular death. We did not see any toxic effect on macrophages J774 at 100 µg/mL, LD50/24h= 233.52 µg/mL. These results revealed a novel pharmacological activity of alkaloids from E. coronaria against amastigotes of L. braziliensis IC50 = 2.6 and 12.4 µg/mL without toxicity on host cells.

  6. Combining diagnostic procedures for the management of leishmaniasis in areas with high prevalence of Leishmania guyanensis Procedimentos diagnósticos combinados no manejo da leishmaniose em áreas com alta prevalência de Leishmania guyanensis

    OpenAIRE

    Ednelza de Almeida Benicio; Ellen Pricilla Nunes Gadelha; Anette Talhari; Roberto Moreira da Silva Jr; Luis Carlos Ferreira; Mayara Cristina Cordeiro dos Santos; Marcelo Távora Mira; Cintia Mara Costa de Oliveira; Carolina Talhari; Sinésio Talhari; Paulo Roberto Machado; Albert Schriefer

    2011-01-01

    BACKGROUND: The Amazon region corresponds to approximately 40% of the cases of leishmaniasis in Brazil. We report a prospective study with 180 patients conducted in a health care unit that diagnoses 10% of the cases of leishmaniasis in the Brazilian Amazon. The study addresses how a combination of procedures improves diagnosis in areas with high prevalence of Leishmania guyanensis. OBJECTIVES: to evaluate diagnostic methods in areas with high prevalence of Leishmania guyanensis. METHODS: All ...

  7. The transmission of suprapylarian Leishmania by bite of experimentally infected sand flies (Diptera: Psychodidae A trasnmissão de Leishmania suprapilária pela picada do flebotomíneo infectado experimentalmente

    Directory of Open Access Journals (Sweden)

    L. Ryan

    1987-09-01

    Full Text Available Lutzomyia furcata transmitted Leishmania chagasi to a hamster 10 days after being experimentally fed on an infected spleen. An individual female Psychodopygus carrerai carrerai that had fed on a hamster lesion caused by Leishmania mexicana amazonensis transmitted this parasite 6 days later to another hamster. Transmission electron microscopy of this fly's head revealed a small number of degenerate promastigotes in the foregut, but only a few were attached.O protozoário Leishmania (L. chagasi foi transmitido experimentalmente a um hamster pela picada do flebotomíneo Lutzomyia furcata. Os insetos foram infectados através de uma membrana (pele de pinto, utilizando-se formas amastigotas provenientes do baço de um hamster infectado. O baço foi triturado em sangue de coelho. A L. (L. amazonensis foi transmitida a um hamster pela picada do flebotomíneo Psychodopygus c. carrerai, previamente alimentado em lesão de pele de um outro hamster infectado com o parasita. O exame desse flebotomíneo, através de microscópio eletrônico, revelou um número pequeno de flagelados degenerados, livres no lumen do intestino anterior.

  8. Leishmania braziliensis: isolation of carbohydrate-containing antigen and possibility of its use in the immunodiagnosis of American Cutaneous Leishmaniasis / Leishmania braziliensis: isolamento de antígeno contendo carboidrato e a possibilidade de sua aplicação no imunodiagnóstico da Leishmaniose Tegumentar Americana

    Scientific Electronic Library Online (English)

    T. G. V., Silveira; C, Kemmelmeier.

    1995-06-01

    Full Text Available A Leishmania braziliensis é um dos agentes causadores da Leishmaniose Tegumentar Americana (LTA). A cepa 034-JCG, isolada de paciente da região norte do estado do Paraná, Brasil, foi cultivada em meio Blood Agar Base, liofilizada e submetida a extração com fenol-água e o extrato obtido foi tratado c [...] om RNase I. O antígeno contendo carboidrato (Ag-CHO) mostrou-se imunogênico para coelhos e apresentou pelo menos uma fração com poucas cargas negativas em pH 8,2. Este antígeno apresenta reação cruzada com extrato fenólico do meio de cultura usado para o cultivo de promastigotas e com antígenos de superfície de promastigotas. É composto por 24,3% de açúcares totais, dos quais 11,2% de galactose, 7,5% de manose e 5,6% de ribose. As proteínas foram estimadas em 5,4% e fosfato em 18,5%. A atividade antigênica foi mantida após: congelamentos e descongelamentos repetidos; liofilização; aquecimento a 100ºC durante 30 minutos; tratamento com RNase, ácido tricloroacético e periodato de sódio. As linhas obtidas nas reações de precipitação coram-se pelo Ácido Periódico de Schiff. A utilização do Ag-CHO na reação de contraimunoeletroforese para o imunodiagnóstico de LTA mostrou 60% de sensibilidade, e nenhuma reação cruzada com os 5 soros de pacientes com Doença de Chagas testados. O uso deste antígeno com técnicas mais sensíveis, e com um maior número de amostras poderá melhorar estes resultados. Abstract in english Leishmania braziliensis is a causative agent of American Cutaneous Leishmaniasis (ACL). The 034-JCG strain, isolated from a patient from the northern region of Paraná State, Brazil, was cultivated in Blood Agar Base medium, lyophilized and submitted to phenol-water extraction. The extract was treate [...] d with RNase I. The carbohydrate containing-antigen (Ag-CHO) was immunogenic to rabbits and showed at least a fraction with some negative charge at pH 8.2. This antigen showed cross-reactivity with the phenol-water extract of the growth medium used for the culture of promastigotes and with the surface antigens of promastigotes. Its composition is: 24.3% of total sugars, from which 11.2% of galactose, 7.5% of mannose and 5.6% of ribose. Protein content was 5.4% and phosphate 18.5%. The antigenic activity was maintained after: repeated freezing-thawing; lyophilization; heating at 100ºC for 30 minutes; treatment with RNase, trichloroacetic acid and sodium metaperiodate. The precipitin line obtained is Periodic Acid Schiff positive. The application of the Ag-CHO in counterimmunoelectrophoresis reaction for the immunodiagnosis of ACL showed 60% sensitivity, and no cross-reaction with the five sera of Chagas' disease patients tested. The use of this antigen in a more sensitive technique, with more samples of sera, may improve these results.

  9. Differentiation of Leishmania species by FT-IR spectroscopy

    Science.gov (United States)

    Aguiar, Josafá C.; Mittmann, Josane; Ferreira, Isabelle; Ferreira-Strixino, Juliana; Raniero, Leandro

    2015-05-01

    Leishmaniasis is a parasitic infectious disease caused by protozoa that belong to the genus Leishmania. It is transmitted by the bite of an infected female Sand fly. The disease is endemic in 88 countries Desjeux (2001) [1] (16 developed countries and 72 developing countries) on four continents. In Brazil, epidemiological data show the disease is present in all Brazilian regions, with the highest incidences in the North and Northeast. There are several methods used to diagnose leishmaniasis, but these procedures have many limitations, are time consuming, have low sensitivity, and are expensive. In this context, Fourier Transform Infrared Spectroscopy (FT-IR) analysis has the potential to provide rapid results and may be adapted for a clinical test with high sensitivity and specificity. In this work, FT-IR was used as a tool to investigate the promastigotes of Leishmaniaamazonensis, Leishmaniachagasi, and Leishmaniamajor species. The spectra were analyzed by cluster analysis and deconvolution procedure base on spectra second derivatives. Results: cluster analysis found four specific regions that are able to identify the Leishmania species. The dendrogram representation clearly indicates the heterogeneity among Leishmania species. The band deconvolution done by the curve fitting in these regions quantitatively differentiated the polysaccharides, amide III, phospholipids, proteins, and nucleic acids. L. chagasi and L. major showed a greater biochemistry similarity and have three bands that were not registered in L. amazonensis. The L. amazonensis presented three specific bands that were not recorded in the other two species. It is evident that the FT-IR method is an indispensable tool to discriminate these parasites. The high sensitivity and specificity of this technique opens up the possibilities for further studies about characterization of other microorganisms.

  10. Study of cross-reactivity in serum samples from dogs positive for Leishmania sp., Babesia canis and Ehrlichia canis in enzyme-linked immunosorbent assay and indirect fluorescent antibody test Estudo da reatividade cruzada em amostras de soro de cães positivos para Leishmania sp., Babesia canis e Ehrlichia canis, pelo ensaio imunoenzimático indireto e pela reação de imunofluorescência indireta

    Directory of Open Access Journals (Sweden)

    Trícia Maria F. de Sousa Oliveira

    2008-03-01

    Full Text Available To verify the presence of cross-reaction among leishmaniosis, ehrlichiosis and babesiosis in serological diagnostics used in human visceral leishmaniasis control programs, serum samples from leishmaniasis endemic and non-endemic areas were collected and tested by Indirect Fluorescent Antibody (IFAT and Enzyme-linked immunosorbent assay (ELISA. All serum samples from endemic areas were positive for Leishmania sp., by ELISA and IFAT, 51% positive for Babesia canis and 43% for Ehrlichia canis by IFAT. None of the serum samples from non-endemic areas were positive for Leishmania sp., by IFAT, but 67% were positive for B. canis and 78% for E. canis using the same test. When tested by ELISA for Leishmania sp., four samples from non-endemic area were positive. These dogs were then located and no clinical signs, parasites or antibody was detected in new tests for a six month period. Only one of these 4 samples was positive for B. canis by IFAT and ELISA and three for E. canis by IFAT. The results of the work suggest a co-infection in the endemic area and no serological cross-reaction among these parasites by IFAT and ELISA.Para verificar a existência de reação cruzada entre leishmaniose visceral, erliquiose e babesiose, nos testes sorológicos utilizados em programas de controle da leishmaniose visceral humana, amostras de soro canino provenientes de áreas endêmicas e não endêmicas para essa enfermidade, foram testadas pela Reação de Imunofluorescência (RIFI e Ensaio imunoenzimático (ELISA. Todos os soros provenientes de área endêmica foram positivos para Leishmania sp pelo ELISA e RIFI, 51% para Babesia canis e 43% para Ehrlichia canis pela RIFI. Pela RIFI, nenhum dos soros provenientes de área não endêmica foi positivo para Leishmania sp, sendo 67% positivos para B. canis e 78% para E. canis pelo mesmo teste. Quando testados pelo ELISA para Leishmania sp., quatro soros da área não endêmica foram positivos. Os cães foram localizados e nenhum sinal clínico, parasito ou anticorpo foi detectado em novos exames realizados ao longo de seis meses. Os resultados desse trabalho sugerem portanto, a presença de uma co-infecção entre os três parasitos citados nas áreas endêmicas e não a reação cruzada entre eles, nos testes sorológicos de RIFI e ELISA descritos.

  11. Study of cross-reactivity in serum samples from dogs positive for Leishmania sp., Babesia canis and Ehrlichia canis in enzyme-linked immunosorbent assay and indirect fluorescent antibody test / Estudo da reatividade cruzada em amostras de soro de cães positivos para Leishmania sp., Babesia canis e Ehrlichia canis, pelo ensaio imunoenzimático indireto e pela reação de imunofluorescência indireta

    Scientific Electronic Library Online (English)

    Trícia Maria F. de Sousa, Oliveira; Patrícia I., Furuta; Débora de, Carvalho; Rosangela Z., Machado.

    2008-03-01

    Full Text Available Para verificar a existência de reação cruzada entre leishmaniose visceral, erliquiose e babesiose, nos testes sorológicos utilizados em programas de controle da leishmaniose visceral humana, amostras de soro canino provenientes de áreas endêmicas e não endêmicas para essa enfermidade, foram testadas [...] pela Reação de Imunofluorescência (RIFI) e Ensaio imunoenzimático (ELISA). Todos os soros provenientes de área endêmica foram positivos para Leishmania sp pelo ELISA e RIFI, 51% para Babesia canis e 43% para Ehrlichia canis pela RIFI. Pela RIFI, nenhum dos soros provenientes de área não endêmica foi positivo para Leishmania sp, sendo 67% positivos para B. canis e 78% para E. canis pelo mesmo teste. Quando testados pelo ELISA para Leishmania sp., quatro soros da área não endêmica foram positivos. Os cães foram localizados e nenhum sinal clínico, parasito ou anticorpo foi detectado em novos exames realizados ao longo de seis meses. Os resultados desse trabalho sugerem portanto, a presença de uma co-infecção entre os três parasitos citados nas áreas endêmicas e não a reação cruzada entre eles, nos testes sorológicos de RIFI e ELISA descritos. Abstract in english To verify the presence of cross-reaction among leishmaniosis, ehrlichiosis and babesiosis in serological diagnostics used in human visceral leishmaniasis control programs, serum samples from leishmaniasis endemic and non-endemic areas were collected and tested by Indirect Fluorescent Antibody (IFAT) [...] and Enzyme-linked immunosorbent assay (ELISA). All serum samples from endemic areas were positive for Leishmania sp., by ELISA and IFAT, 51% positive for Babesia canis and 43% for Ehrlichia canis by IFAT. None of the serum samples from non-endemic areas were positive for Leishmania sp., by IFAT, but 67% were positive for B. canis and 78% for E. canis using the same test. When tested by ELISA for Leishmania sp., four samples from non-endemic area were positive. These dogs were then located and no clinical signs, parasites or antibody was detected in new tests for a six month period. Only one of these 4 samples was positive for B. canis by IFAT and ELISA and three for E. canis by IFAT. The results of the work suggest a co-infection in the endemic area and no serological cross-reaction among these parasites by IFAT and ELISA.

  12. Evaluation of Leishmania (Leishmania) chagasi strains isolated from dogs originating from two visceral leishmaniasis-endemic areas in Brazil using multilocus enzyme electrophoresis / Avaliação de amostras de Leishmania (Leishmania) chagasi isoladas de cães oriundos de duas áreas endêmicas de leishmaniose visceral no Brasil através da eletroforese de isoenzimas

    Scientific Electronic Library Online (English)

    Carlos Eduardo Ribeiro, Coutinho; Dilvani Oliveira, Santos; Cibele, Baptista; Fabiano Borges, Figueiredo; Maria de Fatima, Madeira.

    2011-10-01

    Full Text Available INTRODUÇÃO: Cães domésticos são considerados os reservatórios mais importantes no ciclo peridoméstico de transmissão de Leishmania (Leishmania) chagasi. No entanto, a variabilidade genética de sub-populações que circulam neste hospedeiro é ainda pouco explorada no Brasil, sendo tal conhecimento de g [...] rande importância no contexto clínico-epidemiológico. MÉTODOS: O objetivo deste estudo foi avaliar e comparar a variabilidade fenotípica de 153 amostras de L. chagasi isoladas de cães oriundos dos municípios do Rio de Janeiro (n = 57) e Belo Horizonte (n = 96), onde a doença é endêmica. Foram selecionadas somente amostras isoladas de pele íntegra e analisadas por eletroforese de isoenzimas (MLEE) empregando nove sistemas enzimáticos (6PG, GPI, NH1 e NH2, G6P, PGM, MDH, ME, IDHNADP). RESULTADOS: Todas as amostras analisadas apresentaram perfil eletroforético idêntico entre si e com a amostra de L. chagasi utilizada como referência neste estudo (MHOM/BR/74/PP75). A análise fenética demonstrou índice de similaridade igual a um para todas as amostras, revelando um compartilhamento de 100% dos caracteres avaliados. CONCLUSÕES: A partir desses resultados, podemos inferir que as populações de L. chagasi que estão circulando nos cães do Rio de Janeiro e Belo Horizonte podem ser agrupadas em um único zimodema. Abstract in english INTRODUCTION: Domestic dogs are the most important reservoir in the peridomestic transmission cycle of Leishmania (Leishmania) chagasi. The genetic variability of subpopulations of this parasite circulating in dogs has not been thoroughly analyzed in Brazil, even though this knowledge has important [...] implications in the clinical-epidemiological context. METHODS: The objective of this study was to evaluate and compare the phenotypic variability of 153 L. chagasi strains isolated from dogs originating from the municipalities of Rio de Janeiro (n = 57) and Belo Horizonte (n = 96), where the disease is endemic. Strains isolated only from intact skin were selected and analyzed by multilocus enzyme electrophoresis using nine enzyme systems (6PG, GPI, NH1 and NH2, G6P, PGM, MDH, ME, and IDHNADP). RESULTS: The electrophoretic profile was identical for all isolates analyzed and was the same as that of the L. chagasi reference strain (MHOM/BR/74/PP75). Phenetic analysis showed a similarity index of one for all strains, with the isolates sharing 100% of the characteristics analyzed. CONCLUSIONS: The results demonstrate that the L. chagasi populations circulating in dogs from Rio de Janeiro and Belo Horizonte belong to a single zymodeme.

  13. Evaluation of Leishmania (Leishmania chagasi strains isolated from dogs originating from two visceral leishmaniasis-endemic areas in Brazil using multilocus enzyme electrophoresis Avaliação de amostras de Leishmania (Leishmania chagasi isoladas de cães oriundos de duas áreas endêmicas de leishmaniose visceral no Brasil através da eletroforese de isoenzimas

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Ribeiro Coutinho

    2011-10-01

    Full Text Available INTRODUCTION: Domestic dogs are the most important reservoir in the peridomestic transmission cycle of Leishmania (Leishmania chagasi. The genetic variability of subpopulations of this parasite circulating in dogs has not been thoroughly analyzed in Brazil, even though this knowledge has important implications in the clinical-epidemiological context. METHODS: The objective of this study was to evaluate and compare the phenotypic variability of 153 L. chagasi strains isolated from dogs originating from the municipalities of Rio de Janeiro (n = 57 and Belo Horizonte (n = 96, where the disease is endemic. Strains isolated only from intact skin were selected and analyzed by multilocus enzyme electrophoresis using nine enzyme systems (6PG, GPI, NH1 and NH2, G6P, PGM, MDH, ME, and IDHNADP. RESULTS: The electrophoretic profile was identical for all isolates analyzed and was the same as that of the L. chagasi reference strain (MHOM/BR/74/PP75. Phenetic analysis showed a similarity index of one for all strains, with the isolates sharing 100% of the characteristics analyzed. CONCLUSIONS: The results demonstrate that the L. chagasi populations circulating in dogs from Rio de Janeiro and Belo Horizonte belong to a single zymodeme.INTRODUÇÃO: Cães domésticos são considerados os reservatórios mais importantes no ciclo peridoméstico de transmissão de Leishmania (Leishmania chagasi. No entanto, a variabilidade genética de sub-populações que circulam neste hospedeiro é ainda pouco explorada no Brasil, sendo tal conhecimento de grande importância no contexto clínico-epidemiológico. MÉTODOS: O objetivo deste estudo foi avaliar e comparar a variabilidade fenotípica de 153 amostras de L. chagasi isoladas de cães oriundos dos municípios do Rio de Janeiro (n = 57 e Belo Horizonte (n = 96, onde a doença é endêmica. Foram selecionadas somente amostras isoladas de pele íntegra e analisadas por eletroforese de isoenzimas (MLEE empregando nove sistemas enzimáticos (6PG, GPI, NH1 e NH2, G6P, PGM, MDH, ME, IDHNADP. RESULTADOS: Todas as amostras analisadas apresentaram perfil eletroforético idêntico entre si e com a amostra de L. chagasi utilizada como referência neste estudo (MHOM/BR/74/PP75. A análise fenética demonstrou índice de similaridade igual a um para todas as amostras, revelando um compartilhamento de 100% dos caracteres avaliados. CONCLUSÕES: A partir desses resultados, podemos inferir que as populações de L. chagasi que estão circulando nos cães do Rio de Janeiro e Belo Horizonte podem ser agrupadas em um único zimodema.

  14. Canine visceral leishmaniasis due to Leishmania (L. infantum chagasi in Amazonian Brazil: comparison of the parasite density from the skin, lymph node and visceral tissues between symptomatic and asymptomatic, seropositive dogs Leishmaniose visceral canina causada por Leishmania (L. infantum chagasi na Amazônia brasileira: comparação da densidade parasitária da pele, linfonodo e vísceras entre cães soropositivos, sintomáticos e assintomáticos

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    Luciana Vieira R. Lima

    2010-10-01

    Full Text Available Canine visceral leishmaniasis (CVL is recognizable by characteristic signs of disease and is highly lethal. The infection, however, may be quite inapparent in some seropositive dogs, and this has raised the polemic question as to whether or not such animals can be a source of infection for Lutzomyia longipalpis, the vector of American visceral leishmaniasis (AVL. In this study we have examined 51 dogs with acute CVL from an AVL area in Pará State, northern Brazil, and compared the parasite density, amastigotes of Leishmania (L. infantum chagasi, in the skin, lymph node and viscera of symptomatic with that of nine asymptomatic but seropositive dogs (IFAT-IgG. Post-mortem biopsy fragments of these tissues were processed by immunohistochemistry, using a polyclonal antibody against Leishmania sp. The X² and Mann Whitney tests were used to evaluate the means of infected macrophage density (p 0.05 in the skin (10.7/mm² x 15.5/mm² and lymph node (6.3/mm² x 8.3/mm², between asymptomatic and symptomatic dogs, respectively. It was higher (p A leishmaniose visceral canina (LVC é reconhecida pelas características clínicas da doença e é altamente letal. A infecção, entretanto, pode ser totalmente assintomática em alguns cães soropositivos, o que tem levantado questão polêmica sobre a possibilidade desses animais, serem ou não uma fonte importante da infecção para o flebotomíneo, Lutzomyia longipalpis, o principal vetor da leishmaniose visceral americana (LVA. Neste estudo foram examinados 51 cães com LVC aguda, provenientes de área endêmica de LVA no Estado do Pará, Brasil, e a carga parasitária, formas amastigotas de Leishmania (L. infantum chagasi, na pele, linfonodo poplíteo e vísceras (fígado e baço foi comparada com a de nove cães assintomáticos soropositivos (IFAT-IgG. Fragmentos de biópsia desses tecidos obtidos post-mortem foram processados para análise através de imunohistoquímica, usando um anticorpo policlonal contra Leishmania sp. Os testes do Qui-quadrado (X² e Mann Whitney foram usados para avaliar as médias da densidade de macrófagos infectados (p 0,05 na densidade de macrófagos infectados da pele (10,7/mm² x 15,5/mm² e do linfonodo (6,3/mm² x 8,3/mm² entre cães assintomáticos e sintomáticos. Entretanto, a densidade de macrófagos infectados da víscera de cães sintomáticos (5,3/mm² foi maior (p < 0,05 que a de cães assintomáticos (1,4/mm². Estes resultados sugerem, fortemente, que cães naturalmente infectados por L. (L. i. chagasi, assintomáticos ou sintomáticos, podem servir como fonte de infecção, principalmente, considerando-se que a densidade de macrófagos infectados da pele (10,7/mm² x 15,5/mm², local onde o flebotomíneo vetor Lu. longipalpis realiza a hematofagia, foi maior (p < 0,05 que as do linfonodo (6,3/mm² x 8.3/mm² e vísceras (1,4/mm²x 5,3/mm².

  15. Evaluation of enzyme-linked immunosorbent assay using crude Leishmania and recombinant antigens as a diagnostic marker for canine visceral leishmaniasis

    OpenAIRE

    Eliza Yoshie do Rosário; Odair Genaro; João C França-Silva; Roberto T da Costa; Wilson Mayrink; Alexandre Barbosa Reis; Mariângela Carneiro

    2005-01-01

    The performances of ELISA assays with different antigen preparations, such as Leishmania amazonensis or L. chagasi lysates and the recombinant antigens rK-39 and rK-26, were compared using sera or eluates from dried blood collected on filter paper to detect anti-Leishmania antibodies in dogs from a visceral leishmaniasis-endemic area in Brazil. Of 115 IFAT-reactive dogs at 1:40 titre, 106 (92.2%) were positive in parasitological exams (skin and/or spleen). These animals were compared to healt...

  16. A novel A2 allele found in Leishmania (Leishmania infantum chagasi Novo alelo do gene A2 descrito em Leishmania (Leishmania infantum chagasi

    Directory of Open Access Journals (Sweden)

    Trícia Maria Ferreira de Sousa Oliveira

    2011-03-01

    Full Text Available Visceral leishmaniasis (VL is a widely spread zoonotic disease. In Brazil the disease is caused by Leishmania (Leishmania infantum chagasi. Peridomestic sandflies acquire the etiological agent by feeding on blood of infected reservoir animals, such as dogs or wildlife. The disease is endemic in Brazil and epidemic foci have been reported in densely populated cities all over the country. Many clinical features of Leishmania infection are related to the host-parasite relationship, and many candidate virulence factors in parasites that cause VL have been studied such as A2 genes. The A2 gene was first isolated in 1994 and then in 2005 three new alleles were described in Leishmania (Leishmania infantum. In the present study we amplified by polymerase chain reaction (PCR and sequenced the A2 gene from the genome of a clonal population of L. (L. infantum chagasi VL parasites. The L. (L. infantum chagasi A2 gene was amplified, cloned, and sequenced in. The amplified fragment showed approximately 90% similarity with another A2 allele amplified in Leishmania (Leishmania donovani and in L.(L. infantum described in literature. However, nucleotide translation shows differences in protein amino acid sequence, which may be essential to determine the variability of A2 genes in the species of the L. (L. donovani complex and represents an additional tool to help understanding the role this gene family may have in establishing virulence and immunity in visceral leishmaniasis. This knowledge is important for the development of more accurate diagnostic tests and effective tools for disease control.A leishmaniose visceral (LV é uma zoonose amplamente disseminada, causada no Brasil pela Leishmania (Leishmania infantum chagasi. Flebotomíneos vetores adquirem o agente etiológico, alimentando-se do sangue de animais contaminados, como cachorros ou animais selvagens. A doença é endêmica no Brasil, e focos de epidemia são relatados em cidades densamente povoadas por todo o país. Muitas manifestações clínicas relacionadas à infecção por Leishmania estão ligadas à relação parasito-hospedeiro, e vários possíveis fatores de virulência dos parasitas, que causam a LV, são alvos de estudo, tais como os genes A2. O gene A2 foi isolado pela primeira vez em 1994 e, em seguida, em 2005, três novos alelos foram descritos em Leishmania (Leishmania infantum. No presente estudo, um fragmento do gene A2 de uma população clonal de L.(L. infantum chagasi foi amplificado por PCR e sua sequência de nucleotídeos determinada. O fragmento mostrou 90% de similaridade com alelos do gene A2 de Leishmania (Leishmania donovani e de L. (L. infantum, descritos na literatura. Entretanto, a tradução da sequência de nucleotídeos mostra diferenças na sequência de aminoácidos da proteína, que podem ser essenciais em determinar a variabilidade do gene A2 em espécies do complexo L. (L. donovani e representa uma ferramenta adicional na compreenssão do papel dessa família de genes na virulência e imunidade da leishmaniose visceral. O conhecimento dessa variação é importante para o desenvolvimento de testes diagnósticos mais precisos e ferramentas mais eficazes no controle da doença.

  17. A novel A2 allele found in Leishmania (Leishmania) infantum chagasi / Novo alelo do gene A2 descrito em Leishmania (Leishmania) infantum chagasi

    Scientific Electronic Library Online (English)

    Trícia Maria Ferreira de Sousa, Oliveira; Elton José Rosas de, Vasconcelos; Andréa Cristina Higa, Nakaghi; Tânia Paula Aquino, Defina; Márcia Mariza Gomes, Jusi; Cristiane Divan, Baldani; Ângela Kaysel, Cruz; Rosangela Zacarias, Machado.

    2011-03-01

    Full Text Available A leishmaniose visceral (LV) é uma zoonose amplamente disseminada, causada no Brasil pela Leishmania (Leishmania) infantum chagasi. Flebotomíneos vetores adquirem o agente etiológico, alimentando-se do sangue de animais contaminados, como cachorros ou animais selvagens. A doença é endêmica no Brasil [...] , e focos de epidemia são relatados em cidades densamente povoadas por todo o país. Muitas manifestações clínicas relacionadas à infecção por Leishmania estão ligadas à relação parasito-hospedeiro, e vários possíveis fatores de virulência dos parasitas, que causam a LV, são alvos de estudo, tais como os genes A2. O gene A2 foi isolado pela primeira vez em 1994 e, em seguida, em 2005, três novos alelos foram descritos em Leishmania (Leishmania) infantum. No presente estudo, um fragmento do gene A2 de uma população clonal de L.(L.) infantum chagasi foi amplificado por PCR e sua sequência de nucleotídeos determinada. O fragmento mostrou 90% de similaridade com alelos do gene A2 de Leishmania (Leishmania) donovani e de L. (L.) infantum, descritos na literatura. Entretanto, a tradução da sequência de nucleotídeos mostra diferenças na sequência de aminoácidos da proteína, que podem ser essenciais em determinar a variabilidade do gene A2 em espécies do complexo L. (L.) donovani e representa uma ferramenta adicional na compreenssão do papel dessa família de genes na virulência e imunidade da leishmaniose visceral. O conhecimento dessa variação é importante para o desenvolvimento de testes diagnósticos mais precisos e ferramentas mais eficazes no controle da doença. Abstract in english Visceral leishmaniasis (VL) is a widely spread zoonotic disease. In Brazil the disease is caused by Leishmania (Leishmania) infantum chagasi. Peridomestic sandflies acquire the etiological agent by feeding on blood of infected reservoir animals, such as dogs or wildlife. The disease is endemic in Br [...] azil and epidemic foci have been reported in densely populated cities all over the country. Many clinical features of Leishmania infection are related to the host-parasite relationship, and many candidate virulence factors in parasites that cause VL have been studied such as A2 genes. The A2 gene was first isolated in 1994 and then in 2005 three new alleles were described in Leishmania (Leishmania) infantum. In the present study we amplified by polymerase chain reaction (PCR) and sequenced the A2 gene from the genome of a clonal population of L. (L.) infantum chagasi VL parasites. The L. (L.) infantum chagasi A2 gene was amplified, cloned, and sequenced in. The amplified fragment showed approximately 90% similarity with another A2 allele amplified in Leishmania (Leishmania) donovani and in L.(L.) infantum described in literature. However, nucleotide translation shows differences in protein amino acid sequence, which may be essential to determine the variability of A2 genes in the species of the L. (L.) donovani complex and represents an additional tool to help understanding the role this gene family may have in establishing virulence and immunity in visceral leishmaniasis. This knowledge is important for the development of more accurate diagnostic tests and effective tools for disease control.

  18. Experimental infection of canine peritoneal macrophages with visceral and dermotropic Leishmania strains

    Scientific Electronic Library Online (English)

    MF, Madeira; EGO, Barbosa-Santos; MCA, Marzochi.

    1999-09-01

    Full Text Available A study was carried out using macrophages cultured from the peritoneal exudate of dogs infected in vitro with three species of Leishmania: L. (L.) chagasi, L. (Viannia) braziliensis and L. (L.) amazonensis with the aim of investigating the growth kinetics and infectivity of these species in the host [...] cell. Results were expressed as the percentage of macrophages infected measured at 24 hr intervals over six days in RPMI - 1640 culture medium at a temperature of 34-35oC. The findings open the possibility of using canine peritoneal cells as a model for the screenning of leishmanicide drugs and to study the pathogenesis of these species.

  19. The fusion of Toxoplasma gondii SAG1 vaccine candidate to Leishmania infantum heat shock protein 83-kDa improves expression levels in tobacco chloroplasts.

    Science.gov (United States)

    Albarracín, Romina M; Becher, Melina Laguía; Farran, Inmaculada; Sander, Valeria A; Corigliano, Mariana G; Yácono, María L; Pariani, Sebastián; López, Edwin Sánchez; Veramendi, Jon; Clemente, Marina

    2015-05-01

    Chloroplast transformation technology has emerged as an alternative platform offering many advantages over nuclear transformation. SAG1 is the main surface antigen of the intracellular parasite Toxoplasma gondii and a promising candidate to produce an anti-T. gondii vaccine. The aim of this study was to investigate the expression of SAG1 using chloroplast transformation technology in tobacco plants. In order to improve expression in transplastomic plants, we also expressed the 90-kDa heat shock protein of Leishmania infantum (LiHsp83) as a carrier for the SAG1 antigen. SAG1 protein accumulation in transplastomic plants was approximately 0.1-0.2 ?g per gram of fresh weight (FW). Fusion of SAG1 to LiHsp83 significantly increased the level of SAG1 accumulation in tobacco chloroplasts (by up to 500-fold). We also evaluated the functionality of the chLiHsp83-SAG1. Three human seropositive samples reacted with SAG1 expressed in transplastomic chLiHsp83-SAG1 plants. Oral immunization with chLiHsp83-SAG1 elicited a significant reduction of the cyst burden that correlated with an increase of SAG1-specific antibodies. We propose the fusion of foreign proteins to LiHsp83 as a novel strategy to increase the expression level of the recombinant proteins using chloroplast transformation technology, thus addressing one of the current challenges for this approach in antigen protein production. PMID:25823559

  20. Clinical profile of naturally infected dogs from an endemic area for “Leishmania chagasi” (infantum) in Bahia State, Brazil Quadro clínico de cães infectados naturalmente por Leishmania chagasi em uma área endêmica do estado da Bahia, Brasil

    OpenAIRE

    Fred da Silva Julião; Rafael Lyra Gaspar da Costa; Diana Vianna Bittencourt; Alisson Azevedo Pinheiro; Silvana Ornelas Santos; Paulo Henrique Palis Aguiar; Washington Luis Conrado dos Santos; Stella Maria Barrouin Melo

    2007-01-01

    The purpose of this study was to report a description of the clinical profile of naturally infected dogs from an endemic area for Leishmania chagasi (infantum)-caused visceral leishmaniosis in Brazil, where a wide range of clinical signs are attributed to the infection in dogs. Sixty one dogs, seropositives for anti-L. chagasi antibodies by ELISA, from the urban and peri urban areas of Jequie, in Bahia State were studied. Each clinical sign of disease was recorded. Parasitological diagnosis o...

  1. Comparison among three polymerase chain reaction assays on detection of DNA from Leishmania in biological samples from patients with american cutaneous leishmaniasis Comparação entre três ensaios de reação em cadeia da polimerase na detecção de DNA de Leishmania, em amostras biológicas de pacientes com leishmaniose tegumentar americana

    Directory of Open Access Journals (Sweden)

    João Guilherme Lino da Silva

    2012-04-01

    Full Text Available INTRODUCTION: The study analyzed positivity of polymerase chain reaction (PCR on detection of DNA from Leishmania in patients' samples. METHODS: Extracted DNA was submitted to L150/L152, 13Y/13Z, and seminested PCR (snPCR. RESULTS: Results were evidenced by bands of approximately 120, 720, and 670 bp for L150/L152, 13Y/13Z, and snPCR, respectively. L150/L152, 13Y/13Z, and snPCR positivity indexes were 76.9, 56.4, and 9.2 (p>0.05, respectively, for suspected and 93.7, 68.7, and 84.4 (pINTRODUÇÃO: Analisou-se a positividade da reação em cadeia da polimerase (PCR na detecção de DNA de Leishmania em pacientes. MÉTODOS: DNA extraído foi submetido a L150/L152, 13Y/13Z e PCR seminested (snPCR. RESULTADOS: Resultados foram evidenciados por bandas de aproximadamente 120; 720 e 670pb para L150/L152, 13Y/13Z e snPCR, respectivamente. Positividades para L150/L152, 13Y/13Z e snPCR foram 76,9; 56,4 e 69,2 (p > 0,05, para suspeitos; e 93,7; 68,7 e 84,4 (p < 0,05 para confirmados, respectivamente. CONCLUSÕES: Resultados preliminares mostraram que os ensaios, principalmente L150/L152 e snPCR, podem detectar DNA de Leishmania e têm potencial para diagnóstico laboratorial das leishmanioses.

  2. Peripheral blood fibrocytes: new information to explain the dynamics of Leishmania infection

    Scientific Electronic Library Online (English)

    Roger Magno, Macedo-Silva; Carina de Lima Pereira dos, Santos; Vanessa Alvaro, Diniz; Jorge Jose de, Carvalho; Camila, Guerra; Suzana, Corte-Real.

    2014-02-01

    Full Text Available Fibrocytes are important for understanding the progression of many diseases because they are present in areas where pathogenic lesions are generated. However, the morphology of fibrocytes and their interactions with parasites are poorly understood. In this study, we examined the morphology of periph [...] eral blood fibrocytes and their interactions with Leishmania (L.) amazonensis . Through ultrastructural analysis, we describe the details of fibrocyte morphology and how fibrocytes rapidly internalise Leishmania promastigotes. The parasites differentiated into amastigotes after 2 h in phagolysosomes and the infection was completely resolved after 72 h. Early in the infection, we found increased nitric oxide production and large lysosomes with electron-dense material. These factors may regulate the proliferation and death of the parasites. Because fibrocytes are present at the infection site and are directly involved in developing cutaneous leishmaniasis, they are targets for effective, non-toxic cell-based therapies that control and treat leishmaniasis.

  3. Comparison among three polymerase chain reaction assays on detection of DNA from Leishmania in biological samples from patients with american cutaneous leishmaniasis / Comparação entre três ensaios de reação em cadeia da polimerase na detecção de DNA de Leishmania, em amostras biológicas de pacientes com leishmaniose tegumentar americana

    Scientific Electronic Library Online (English)

    João Guilherme Lino da, Silva; Thiago Miranda da, Silva; Eduardo de Figueiredo, Peloso; George Luiz Lins, Machado-Coelho; Wilson, Mayrink; Marília Caixeta Franco, Ariosa; Paulo Márcio de, Faria e Silva; Marcos José, Marques.

    2012-04-01

    Full Text Available INTRODUÇÃO: Analisou-se a positividade da reação em cadeia da polimerase (PCR) na detecção de DNA de Leishmania em pacientes. MÉTODOS: DNA extraído foi submetido a L150/L152, 13Y/13Z e PCR seminested (snPCR). RESULTADOS: Resultados foram evidenciados por bandas de aproximadamente 120; 720 e 670pb pa [...] ra L150/L152, 13Y/13Z e snPCR, respectivamente. Positividades para L150/L152, 13Y/13Z e snPCR foram 76,9; 56,4 e 69,2 (p > 0,05), para suspeitos; e 93,7; 68,7 e 84,4 (p Abstract in english INTRODUCTION: The study analyzed positivity of polymerase chain reaction (PCR) on detection of DNA from Leishmania in patients' samples. METHODS: Extracted DNA was submitted to L150/L152, 13Y/13Z, and seminested PCR (snPCR). RESULTS: Results were evidenced by bands of approximately 120, 720, and 670 [...] bp for L150/L152, 13Y/13Z, and snPCR, respectively. L150/L152, 13Y/13Z, and snPCR positivity indexes were 76.9, 56.4, and 9.2 (p>0.05), respectively, for suspected and 93.7, 68.7, and 84.4 (p

  4. Leishmania braziliensis: isolation of carbohydrate-containing antigen and possibility of its use in the immunodiagnosis of American Cutaneous Leishmaniasis Leishmania braziliensis: isolamento de antígeno contendo carboidrato e a possibilidade de sua aplicação no imunodiagnóstico da Leishmaniose Tegumentar Americana

    OpenAIRE

    T.G.V. Silveira; C Kemmelmeier

    1995-01-01

    Leishmania braziliensis is a causative agent of American Cutaneous Leishmaniasis (ACL). The 034-JCG strain, isolated from a patient from the northern region of Paraná State, Brazil, was cultivated in Blood Agar Base medium, lyophilized and submitted to phenol-water extraction. The extract was treated with RNase I. The carbohydrate containing-antigen (Ag-CHO) was immunogenic to rabbits and showed at least a fraction with some negative charge at pH 8.2. This antigen showed cross-reactivity with...

  5. Evaluación de la respuesta de isotipos de inmunoglobulina especifica a Leishmania en leishmaniasis tegumentaria Americana / Evaluation of specific immunoglobin isotype response to Leishmania in American tegumentary leishmaniasis

    Scientific Electronic Library Online (English)

    Maricel, Labrada; Kristen, Weigle; Liliana, Valderrama; Nancy G., Saravia.

    1989-09-01

    Full Text Available Con el fin de determinar las clases de anticuerpo producido contra el parásito y la cinética de los mismos en relación a la evolución de la infección, se estudiaron los sueros de 133 pacientes infectados con Leishmania del complejo braziliensis. Se utilizó la prueba de inmunofluorescencia indirecta [...] y amastigotas de L. mexicana amazonensis como antígeno. En los sueros obtenidos al momento de consultar para el diagnóstico se encontró IgM en 54 de los sueros absorbidos con Straphylococcus aureus Cowan I y en 5 de los no absorbidos. La IgM sólo se encontro en los sueros de pacientes con tiempo devolución de las lesiones Abstract in english Leishmania-specific immunoglobulin subclass response was evaluated in 133 patients infected with Leishmania braziliensis. The indirect immunofluorescent antibody test (IFAT) was employed with amastigotes of L. mexicana amazonensis as antigen. Among the 133 sera obtained at consultation fo rdiagnosis [...] of active lesions, IgM was detected in 54 following absorption with Staphylococcus aureus Cowan strain I, and in 5 sera prior to absorption. IgM reactive with Leishmania antigen was only found in sera from patients whose lesions had envolved over past two months or less. Leishmania-specific IgG was detected in all sera prior to absorption. Sera obtained at the time of recurrence of after complete healing of lesions presented only specific IgC. The combined use of the Montenegro skin test and specific IgM increased the sensitivity of immunodiagnostic methods in patients with lesions of less than 2 months duration. Normal control volunteers were negative for specific IgM and unreactive to Montenegro skin testin. Among 16 patients with non-leishmanial lesion, 3 with sporotrichosis showed IgG reactive with Leishmania; none, including 4 with lesions of less than two months duration, showed specific IgM. We conclude that in patients infected with L. brasiliensis the presence of specific IgG and IgM is associated with the time of lesion evolution and the primary or recurrent nature of the lesions. In addition, the combined use of IgM titer and Montenegro reactivity is of potential utility in the diagnosis of early lesions.

  6. Leishmania mexicana: aspectos taxonómicos y rareza de la infección humana en Três Braços, Bahia, Brasil

    Scientific Electronic Library Online (English)

    César Augusto Cuba, Cuba; Air Colombo, Barreto; Philip Davis, Marsden.

    1984-09-01

    Full Text Available Del estúdio de 51 stocks de Leishmania aislados de pacientes humanos de leishmaniasis cutaneomucosa en Três Braços, Bahia, Brasil, los autores describen, en detalle, el análisis de los dos únicos stocks de L. mexicana, identificando uno de ellos como L. mexicana amazonensis. El otro aislado permanec [...] e en posición taxonómica no definida pues considerándosele como un miembro de L. mexicana, encuéntranse dificultades para su identificación subespecífica. Evaluan también los parâmetros biológicos e isoenzimáticos y discuten el papel de los anticuerpos monoclonales en la tipificación de éstos stocks. Los autores remarcan la rareza de la transmisión de parásitos del complejo L. mexicana en esta región, aun cuando estudien epidemiológicamente por mais de 8 anos la infección humana. Abstract in english In a study of 51 stocks of Leishmania isolated from patients with cutaneous leishmaniasis in Três Braços, Bahia, Brazil 49 were characterized as L. braziliensis braziliensis. Only two L. mexicana stocks were identified. One was subspeciated as L. mexicana amazonensis. The other differed from this sp [...] ecies and to date remains unspeciated. The biological parameters, isoenzyme analysis and monoclonal antibody findings relating to these two strains are discussed. Transmission of parasites of the mexicana complex to man have been rare in this region during the 8 years of study of the human infection.

  7. Leishmania mexicana: aspectos taxonómicos y rareza de la infección humana en Três Braços, Bahia, Brasil

    Directory of Open Access Journals (Sweden)

    César Augusto Cuba Cuba

    1984-09-01

    Full Text Available Del estúdio de 51 stocks de Leishmania aislados de pacientes humanos de leishmaniasis cutaneomucosa en Três Braços, Bahia, Brasil, los autores describen, en detalle, el análisis de los dos únicos stocks de L. mexicana, identificando uno de ellos como L. mexicana amazonensis. El otro aislado permanece en posición taxonómica no definida pues considerándosele como un miembro de L. mexicana, encuéntranse dificultades para su identificación subespecífica. Evaluan también los parâmetros biológicos e isoenzimáticos y discuten el papel de los anticuerpos monoclonales en la tipificación de éstos stocks. Los autores remarcan la rareza de la transmisión de parásitos del complejo L. mexicana en esta región, aun cuando estudien epidemiológicamente por mais de 8 anos la infección humana.In a study of 51 stocks of Leishmania isolated from patients with cutaneous leishmaniasis in Três Braços, Bahia, Brazil 49 were characterized as L. braziliensis braziliensis. Only two L. mexicana stocks were identified. One was subspeciated as L. mexicana amazonensis. The other differed from this species and to date remains unspeciated. The biological parameters, isoenzyme analysis and monoclonal antibody findings relating to these two strains are discussed. Transmission of parasites of the mexicana complex to man have been rare in this region during the 8 years of study of the human infection.

  8. Estudo da competência vetorial de Lutzomyia intermedia (Lutz & Neiva, 1912 para Leishmania (Viannia braziliensis, Vianna, 1911 Study of the vectorial competence of Lutzomyia intermedia (Lutz & Neiva, 1912 to Leishmania (Viannia braziliensis, Vianna, 1911

    Directory of Open Access Journals (Sweden)

    Antonio Carlos da Silva

    2001-04-01

    Full Text Available Estudou-se a competência vetorial de Lutzomyia intermedia (Diptera: Psychodidae do Vale do Ribeira (SP para estirpes de Leishmania (Viannia braziliensis (Kinetoplastida: Trypanosomatidae, mediante pesquisa de infectividade natural; exposições de fêmeas silvestres e colonizadas (F1 às lesões de hamsters experimentalmente infectados e testes de transmissão via picada. A infectividade natural e os testes de transmissão revelaram-se negativos e, nas exposições, foram obtidas positividades de 74% (123+/166 dissecados e 70% (115+/164 dissecados para fêmeas silvestres e colonizadas respectivamente, e o desenvolvimento das formas evolutivas compatíveis com o modelo Peripilaria. A suscetibilidade às estirpes testadas associada aos indicadores epidemiológicos concorrem para a suspeita do papel vetorial de Lutzomyia intermedia na região estudada.This paper investigated the vectorial competence of Lutzomyia intermedia (Diptera: Psychodidae in Vale do Ribeira (SP to strains of Leishmania (Viannia braziliensis (Kinetoplastida: Trypanosomatidae, by means of a search for natural infection; exposure of wild and colonized females (F1 to the lesions of experimentally infected hamsters and transmission tests by bite. The natural infection and the transmission tests were negative. In the exposures of Lu. intermedia to infected lesions we found rates of 74% (123+/166 dissected and 70% (115+/164 dissected for the wild and colonized females respectively. The development of the parasites was compatible with the development model of Peripilaria. The susceptibility of the tested strains associated with the epidemiological indicators contribute to the vectorial role suspicion of Lutzomyia intermedia in the studied region.

  9. Estudo, ao microscópio óptico e eletrônico, do rim de caes natural e experimentalmente infectados com Leishmania (Leishmania) chagasi Optical and electron microscopical studies of canine kidney naturally and experimentally infected with Leishmania (Leishmania) chagasi

    OpenAIRE

    Washington Luiz Tafuri; Marilena Suzan Marques Michalick; Magno Dias; Odair Genaro; Virginia Hora Rios Leite; Alfredo José Afonso Barbosa; Eduardo Alves Bambirra; Carlos Alberto Da Costa; Maria Norma Melo; Wilson Mayrink

    1989-01-01

    Os autores estudam os rins de 4 cães infectados com Leishmania (Leishmania) chagasi. Dois animais (um macho e uma fêmea) naturalmente infectados foram sacrificados 18 meses após sua permanência no laboratório. Dois machos foram inoculados por via endovenosa, com lxlO6 promastigotas da cepa MHO/BR/70/BH46 e sacrificados após 18 meses e 2 anos, respectivamente. Em todos os animais os rins estavam lesados. As alterações encontradas foram: (1) glomerulonefrite mesangioproliferativa focal ou difus...

  10. Leishmania Exploit Sex

    Science.gov (United States)

    Michael Miles (London School of Hygiene and Tropical Medicine; )

    2009-04-10

    Access to the article is free, however registration and sign-in are required. Leishmania are the last of the three major groups of trypanosomatid parasites to give up their secret--a healthy capacity for genetic exchange.

  11. Iron uptake controls the generation of Leishmania infective forms through regulation of ROS levels

    Science.gov (United States)

    Mittra, Bidyottam; Cortez, Mauro; Haydock, Andrew; Ramasamy, Gowthaman; Myler, Peter J.

    2013-01-01

    During its life cycle, Leishmania undergoes extreme environmental changes, alternating between insect vectors and vertebrate hosts. Elevated temperature and decreased pH, conditions encountered after macrophage invasion, can induce axenic differentiation of avirulent promastigotes into virulent amastigotes. Here we show that iron uptake is a major trigger for the differentiation of Leishmania amazonensis amastigotes, independently of temperature and pH changes. We found that iron depletion from the culture medium triggered expression of the ferrous iron transporter LIT1 (Leishmania iron transporter 1), an increase in iron content of the parasites, growth arrest, and differentiation of wild-type (WT) promastigotes into infective amastigotes. In contrast, LIT1-null promastigotes showed reduced intracellular iron content and sustained growth in iron-poor media, followed by cell death. LIT1 up-regulation also increased iron superoxide dismutase (FeSOD) activity in WT but not in LIT1-null parasites. Notably, the superoxide-generating drug menadione or H2O2 was sufficient to trigger differentiation of WT promastigotes into fully infective amastigotes. LIT1-null promastigotes accumulated superoxide radicals and initiated amastigote differentiation after exposure to H2O2 but not to menadione. Our results reveal a novel role for FeSOD activity and reactive oxygen species in orchestrating the differentiation of virulent Leishmania amastigotes in a process regulated by iron availability. PMID:23382545

  12. Leishmania isoenzyme polymorphisms in Ecuador: Relationships with geographic distribution and clinical presentation

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    Mimori Tatsuyuki

    2006-09-01

    Full Text Available Abstract Background Determinants of the clinical presentation of the leishmaniases are poorly understood but Leishmania species and strain differences are important. To examine the relationship between clinical presentation, species and isoenzyme polymorphisms, 56 Leishmania isolates from distinct presentations of American tegumentary leishmaniasis (ATL from Ecuador were analyzed. Methods Isolates were characterized by multilocus enzyme electrophoresis for polymorphisms of 11 isoenzymes. Patients were infected in four different ecologic regions: highland and lowland jungle of the Pacific coast, Amazonian lowlands and Andean highlands. Results Six Leishmania species constituting 21 zymodemes were identified: L. (Viannia panamensis (21 isolates, 7 zymodemes, L. (V. guyanensis (7 isolates, 4 zymodemes, L. (V. braziliensis (5 isolates, 3 zymodemes, L. (Leishmania mexicana (11 isolates, 4 zymodemes, L. (L. amazonensis (10 isolates, 2 zymodemes and L. (L. major (2 isolates, 1 zymodeme. L. panamensis was the species most frequently identified in the Pacific region and was associated with several clinical variants of cutaneous disease (CL; eight cases of leishmaniasis recidiva cutis (LRC found in the Pacific highlands were associated with 3 zymodemes of this species. Mucocutaneous leishmaniasis found only in the Amazonian focus was associated with 3 zymodemes of L. braziliensis. The papular variant of CL, Uta, found in the Andean highlands was related predominantly with a single zymodeme of L. mexicana. Conclusion Our data show a high degree of phenotypic variation within species, and some evidence for associations between specific variants of ATL (i.e. Uta and LRC and specific Leishmania zymodemes. This study further defines the geographic distribution of Leishmania species and clinical variants of ATL in Ecuador.

  13. Immunoperoxidase technique using an anti-Leishmania (L.) chagasi hyperimmune serum in the diagnosis of culture-confirmed American tegumentary leishmaniasis Técnica da imunoperoxidase utilizando um soro hiperimune anti-Leishmania (L.) chagasi no diagnóstico da leishmaniose tegumentar americana confirmada por cultura

    OpenAIRE

    Leonardo P. Quintella; Tullia Cuzzi; Maria F. Madeira; Thais Okamoto; Schubach, Armando O

    2009-01-01

    The present study reports the production of the rabbit anti-Leishmania (L.) chagasi hyperimmune serum, the standardization of the immunohistochemistry (IHC) technique and the evaluation of its employment in cutaneous leishmaniasis (CL) lesions diagnosed by Leishmania sp. culture isolation. Thirty fragments of active CL lesions were examined as well as 10 fragments of cutaneous mycosis lesions as control group. IHC proved more sensitive in detecting amastigotes than conventional hematoxylin-eo...

  14. In vitro and in vivo antileishmanial efficacy of a combination therapy of diminazene and artesunate against Leishmania donovani in BALB/c mice / Estudo in vitro e in vivo da eficácia anti leishmaniótica de terapêutica combinada de Diminazene e Artesunate contra Leishmania donovani em camundongos Balb/c

    Scientific Electronic Library Online (English)

    Joshua Muli, Mutiso; John Chege, Macharia; Mustafa, Barasa; Evans, Taracha; Alain J., Bourdichon; Michael M., Gicheru.

    2011-06-01

    Full Text Available A atividade in vitro e in vivo de Diminazene (Dim), Artezunate (Art) e a combinação Dim e Art (Dim-Art) contra Leishmania donovani foi comparada com a droga de referência Anfotericina B. IC50 da Dim-Art foi 2,28 ± 0,24 µg/mL enquanto aquelas de Dim e Art foram 9,16 ± 0,3 µg/mL e 4,64 ± 0,48 µg/mL re [...] spectivamente. O IC50 da Anfotericina B foi 0,16 ± 0,32 µg/mL contra a fase estacionária de promastigotas. A avaliação in vivo do modelo de L. donovani em camundongos Balb/c indicou que os tratamentos com a terapêutica de drogas combinadas em doses de 12,5 mg/kg por 28 dias consecutivos significantemente (p Abstract in english The in vitro and in vivo activity of diminazene (Dim), artesunate (Art) and combination of Dim and Art (Dim-Art) against Leishmania donovani was compared to reference drug; amphotericin B. IC50 of Dim-Art was found to be 2.28 ± 0.24 µg/mL while those of Dim and Art were 9.16 ± 0.3 µg/mL and 4.64 ± 0 [...] .48 µg/mL respectively. The IC50 for Amphot B was 0.16 ± 0.32 µg/mL against stationary-phase promastigotes. In vivo evaluation in the L. donovani BALB/c mice model indicated that treatments with the combined drug therapy at doses of 12.5 mg/kg for 28 consecutive days significantly (p

  15. An outbreak of american cutaneous leishmaniasis (Leishmania braziliensis braziliensis) in a periurban area of Rio de Janeiro city, Brazil: clinical and epidemiological studies / Um surto de leishmaniose cutânea americana (Leishmania braziliensis braziliensis) numa área periurbana da cidade do Rio de Janeiro, Brasil: estudos clínicos e epidemiológicos

    Scientific Electronic Library Online (English)

    Manoel P., Oliveira-Neto; Claude, Pirmez; Elizabeth, Rangel; Armando, Schubach; Gabriel, Grimaldi Júnior.

    1988-12-01

    Full Text Available De julho de 1984 a setembro de 1986, 105 casos de leishmaniose cutânea foram estudados numa localidade situada na imediata vizinhança da área urbanizada da região metropolitana da cidade do Rio de Janeiro. A ocupação do sítio deu-se aproximadamente há 20 anos, mas os primeiros casos foram registrado [...] s somente seis meses antes do início de nosso estudo. Os casos eram quase que exclusivamente cutâneos, da forma clínica ulcerada com um e seis meses de evolução. O teste de Montenegro foi positivo em todos os casos e anticorpos antileishmania foram detectados por imunofluorescência indireta em 74,3% dos pacientes. A demonstração do parasito foi obtida em 69,5%. Animais domésticos infectados foram facilmente encontrados: 32% dos cães examinados e 30,8% dos equinos mostravam presença de leishmânia em lesões ulceradas. Parasitos isolados, tanto de casos humanos como de cães e equinos, foram imulogicamente caracterizados e identificados com L. b. braziliensis. Da população de flebotomíneos encontrados 73% eram de Lutzomyia intermedia capturados principalmente com iscas humanas e de animais domésticos. Nossas observações sugerem que esta é uma área de estabelecimento recente da infecção por L. b. braziliensis e que a transmissão ocorre provavelmente tanto no peridomicílio como no interior das habitações. Abstract in english From July 1984 to September 1986, 105 cases of American cutaneous leishmaniasis were studied in a locality closely situated to an urbanized area of the city of Rio de Janeiro, Brazil. Settement in this area was established at least 20 years ago but the first cases were noted six months prior to the [...] beginning of this study. Cases were almost exlusively cutaneous and ulcerated, with one to six months of evolution. Montenegro's skin tests were positive in all cases and anti-Leishmania antibodies were detected by indirect immunofluorescence test in 74.3% of the patients. Parasites were demonstrated in 69.5% of cases. Domestic animals were easily found infected; 32% of the examined dogs and 30.8% of the examined equines were positive to the presence of Leishmania in cutaneous ulcerated lesions. Parasite isolates from human, dog andequines were immunologically characterized and identified as L. b. braziliensis. 73,0% of the sandfly population were Lutzomyia intermedia mainly caught on human baits and on domestic animals. Our observations suggest that this is an area of recent established L. b. braziliensis infection and that transmission probably occurs indoors or outdoors close to the houses.

  16. An outbreak of american cutaneous leishmaniasis (Leishmania braziliensis braziliensis in a periurban area of Rio de Janeiro city, Brazil: clinical and epidemiological studies Um surto de leishmaniose cutânea americana (Leishmania braziliensis braziliensis numa área periurbana da cidade do Rio de Janeiro, Brasil: estudos clínicos e epidemiológicos

    Directory of Open Access Journals (Sweden)

    Manoel P. Oliveira-Neto

    1988-12-01

    Full Text Available From July 1984 to September 1986, 105 cases of American cutaneous leishmaniasis were studied in a locality closely situated to an urbanized area of the city of Rio de Janeiro, Brazil. Settement in this area was established at least 20 years ago but the first cases were noted six months prior to the beginning of this study. Cases were almost exlusively cutaneous and ulcerated, with one to six months of evolution. Montenegro's skin tests were positive in all cases and anti-Leishmania antibodies were detected by indirect immunofluorescence test in 74.3% of the patients. Parasites were demonstrated in 69.5% of cases. Domestic animals were easily found infected; 32% of the examined dogs and 30.8% of the examined equines were positive to the presence of Leishmania in cutaneous ulcerated lesions. Parasite isolates from human, dog andequines were immunologically characterized and identified as L. b. braziliensis. 73,0% of the sandfly population were Lutzomyia intermedia mainly caught on human baits and on domestic animals. Our observations suggest that this is an area of recent established L. b. braziliensis infection and that transmission probably occurs indoors or outdoors close to the houses.De julho de 1984 a setembro de 1986, 105 casos de leishmaniose cutânea foram estudados numa localidade situada na imediata vizinhança da área urbanizada da região metropolitana da cidade do Rio de Janeiro. A ocupação do sítio deu-se aproximadamente há 20 anos, mas os primeiros casos foram registrados somente seis meses antes do início de nosso estudo. Os casos eram quase que exclusivamente cutâneos, da forma clínica ulcerada com um e seis meses de evolução. O teste de Montenegro foi positivo em todos os casos e anticorpos antileishmania foram detectados por imunofluorescência indireta em 74,3% dos pacientes. A demonstração do parasito foi obtida em 69,5%. Animais domésticos infectados foram facilmente encontrados: 32% dos cães examinados e 30,8% dos equinos mostravam presença de leishmânia em lesões ulceradas. Parasitos isolados, tanto de casos humanos como de cães e equinos, foram imulogicamente caracterizados e identificados com L. b. braziliensis. Da população de flebotomíneos encontrados 73% eram de Lutzomyia intermedia capturados principalmente com iscas humanas e de animais domésticos. Nossas observações sugerem que esta é uma área de estabelecimento recente da infecção por L. b. braziliensis e que a transmissão ocorre provavelmente tanto no peridomicílio como no interior das habitações.

  17. Estudo clínico randomizado comparando antimoniato de meglumina, pentamidina e anfotericina B para o tratamento da leishmaniose cutânea ocasionada por Leishmania guyanensis / A randomized clinical trial comparing meglumine antimoniate, pentamidine and amphotericin B for the treatment of cutaneous leishmaniasis by Leishmania guyanensis

    Scientific Electronic Library Online (English)

    Leandro Ourives, Neves; Anette Chrusciak, Talhari; Ellen Priscilla Nunes, Gadelha; Roberto Moreira da, Silva Júnior; Jorge Augusto de Oliveira, Guerra; Luiz Carlos de Lima, Ferreira; Sinésio, Talhari.

    2011-12-01

    Full Text Available FUNDAMENTOS: O tratamento da leishmaniose tegumentar americana (LTA) ainda constitui desafio, pois a maioria dos medicamentos é injetável e têm-se poucos ensaios clínicos randomizados comparando a eficácia das drogas. Além disso, é provável que as espécies de Leishmania tenham influência nas respost [...] as terapêuticas. OBJETIVOS: Avaliar e comparar a eficácia e a segurança dos esquemas de tratamento na LTA, ocasionada por Leishmania (Viannia) guyanensis. MÉTODOS: 185 pacientes foram selecionados, conforme critérios de elegibilidade, e distribuídos, aleatoriamente, em 3 grupos - 2 com 74 enfermos e outro com 37 - que receberam, respectivamente, antimoniato de meglumina, isotionato de pentamidina e anfotericina B em doses, períodos e vias de administração padronizados. Os enfermos foram reexaminados um, dois e seis meses após o final dos tratamentos. RESULTADOS: Não houve diferença entre os grupos terapêuticos em relação ao sexo, idade, número ou local das lesões. A análise por intenção de tratar (ITT) mostrou eficácias de 58,1% para a pentamidina e 55,5% para o antimoniato (p=0,857). O grupo da anfotericina B foi analisado separadamente, pois 28 (75,7%) pacientes negaram-se a continuar no estudo após a randomização. Eventos adversos leves ou moderados foram relatados por 74 (40%) pacientes, principalmente artralgia (20,3%), para o grupo do antimoniato, e dor (35,1%) ou enduração (10,8%) no local das injeções para a pentamidina. CONCLUSÕES: A pentamidina tem eficácia similar ao antimonial pentavalente para o tratamento da LTA ocasionada por L. guyanensis. Face aos baixos resultados de eficácia apresentados por ambas as drogas, necessita-se, com urgência, investigar novas opções terapêuticas para esta enfermidade. Abstract in english FUNDAMENTALS: American tegumentary leishmaniasis (ATL) treatment remains a challenge, since most available drugs are injectable and only a small number of comparative, randomized clinical trials have been performed to support their use. Moreover, treatment outcome may depend on the causative species [...] of Leishmania. OBJECTIVES: To evaluate and compare the efficacy and tolerability of meglumine antimoniate, pentamidine isethionate, and amphotericin B in the treatment of ATL caused by Leishmania (Viannia) guyanensis. METHODS: 185 patients were selected according to the eligibility criteria and randomly allocated into three groups - two groups with 74 patients each, and one group with 37 patients, which underwent meglumine, pentamidine and amphotericin B treatment, respectively. Doses, mode of administration and time periods of treatment followed the current recommendations for each drug. Patients were re-examined one, two and six months after completion of treatment. RESULTS: No differences were observed among the therapeutic groups in relation to gender, age, number or site of lesions. Intention-to-treat (ITT) analysis showed efficacy of 58.1% for pentamidine and 55.5% for meglumine (p=0.857). The amphotericin B group was analyzed separately, since 28 patients (75.7%) in this group refused to continue participating in the study. Mild or moderate adverse effects were reported by 74 (40%) patients, especially arthralgia (20.3%) in the meglumine group, and pain (35.1%) or induration (10.8%) at the site of injection in the pentamidine group. CONCLUSION: Pentamidine and meglumine show similar efficacy in the treatment of ATL caused by L. guyanensis. Given the low efficacy of both drugs, there is an urgent need for new therapeutical approaches.

  18. Estudo clínico randomizado comparando antimoniato de meglumina, pentamidina e anfotericina B para o tratamento da leishmaniose cutânea ocasionada por Leishmania guyanensis A randomized clinical trial comparing meglumine antimoniate, pentamidine and amphotericin B for the treatment of cutaneous leishmaniasis by Leishmania guyanensis

    Directory of Open Access Journals (Sweden)

    Leandro Ourives Neves

    2011-12-01

    Full Text Available FUNDAMENTOS: O tratamento da leishmaniose tegumentar americana (LTA ainda constitui desafio, pois a maioria dos medicamentos é injetável e têm-se poucos ensaios clínicos randomizados comparando a eficácia das drogas. Além disso, é provável que as espécies de Leishmania tenham influência nas respostas terapêuticas. OBJETIVOS: Avaliar e comparar a eficácia e a segurança dos esquemas de tratamento na LTA, ocasionada por Leishmania (Viannia guyanensis. MÉTODOS: 185 pacientes foram selecionados, conforme critérios de elegibilidade, e distribuídos, aleatoriamente, em 3 grupos - 2 com 74 enfermos e outro com 37 - que receberam, respectivamente, antimoniato de meglumina, isotionato de pentamidina e anfotericina B em doses, períodos e vias de administração padronizados. Os enfermos foram reexaminados um, dois e seis meses após o final dos tratamentos. RESULTADOS: Não houve diferença entre os grupos terapêuticos em relação ao sexo, idade, número ou local das lesões. A análise por intenção de tratar (ITT mostrou eficácias de 58,1% para a pentamidina e 55,5% para o antimoniato (p=0,857. O grupo da anfotericina B foi analisado separadamente, pois 28 (75,7% pacientes negaram-se a continuar no estudo após a randomização. Eventos adversos leves ou moderados foram relatados por 74 (40% pacientes, principalmente artralgia (20,3%, para o grupo do antimoniato, e dor (35,1% ou enduração (10,8% no local das injeções para a pentamidina. CONCLUSÕES: A pentamidina tem eficácia similar ao antimonial pentavalente para o tratamento da LTA ocasionada por L. guyanensis. Face aos baixos resultados de eficácia apresentados por ambas as drogas, necessita-se, com urgência, investigar novas opções terapêuticas para esta enfermidade.FUNDAMENTALS: American tegumentary leishmaniasis (ATL treatment remains a challenge, since most available drugs are injectable and only a small number of comparative, randomized clinical trials have been performed to support their use. Moreover, treatment outcome may depend on the causative species of Leishmania. OBJECTIVES: To evaluate and compare the efficacy and tolerability of meglumine antimoniate, pentamidine isethionate, and amphotericin B in the treatment of ATL caused by Leishmania (Viannia guyanensis. METHODS: 185 patients were selected according to the eligibility criteria and randomly allocated into three groups - two groups with 74 patients each, and one group with 37 patients, which underwent meglumine, pentamidine and amphotericin B treatment, respectively. Doses, mode of administration and time periods of treatment followed the current recommendations for each drug. Patients were re-examined one, two and six months after completion of treatment. RESULTS: No differences were observed among the therapeutic groups in relation to gender, age, number or site of lesions. Intention-to-treat (ITT analysis showed efficacy of 58.1% for pentamidine and 55.5% for meglumine (p=0.857. The amphotericin B group was analyzed separately, since 28 patients (75.7% in this group refused to continue participating in the study. Mild or moderate adverse effects were reported by 74 (40% patients, especially arthralgia (20.3% in the meglumine group, and pain (35.1% or induration (10.8% at the site of injection in the pentamidine group. CONCLUSION: Pentamidine and meglumine show similar efficacy in the treatment of ATL caused by L. guyanensis. Given the low efficacy of both drugs, there is an urgent need for new therapeutical approaches.

  19. Infecção natural de Lutzomyia longipalpis por Leishmania sp. em Teresina, Piauí, Brasil Natural infection of Lutzomyia longipalpis by Leishmania sp. in Teresina, Piauí State, Brazil

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    Jackellyne Geórgia Dutra e Silva; Werneck, Guilherme L; Cruz, Maria do Socorro Pires e; Carlos Henrique Nery Costa; Ivete Lopes de Mendonça

    2007-01-01

    No Brasil, o controle do vetor Lutzomyia longipalpis é uma das principais estratégias utilizadas para limitar a expansão da leishmaniose visceral americana. Entretanto, poucos são os estudos sobre a infecção natural destes flebotomíneos por espécies de Leishmania. Um estudo sobre a infecção natural de Lu. longipalpis por Leishmania sp. foi realizado no bairro Bela Vista, Teresina, Piauí, um dos principais focos urbanos da leishmaniose visceral americana no Brasil. Entre fevereiro de 2004 e ja...

  20. DISEÑO Y PRODUCCIÓN DE UNA HERRAMIENTA MOLECULAR PARA EL ESTUDIO DEL N-TERMINAL DE LA NICOTINAMIDA MONONUCLEÓTIDO ADENILIL TRANSFERASA (NMNAT) EN Leishmania braziliensis / DESIGN AND PRODUCTION OF A MOLECULAR TOOL TO STUDY OF N-TERMINAL NICOTINAMIDE MONONUCLEOTIDE ADENYLYL TRANSFERASE (NMNAT) IN Leishmania braziliensis / DESIGN E PRODUÇÃO DE UMA FERRAMENTA MOLECULAR PARA O ESTUDO DO TERMINALN DA NICOTINAMIDA CICLASE MONONUCLEÓTIDO TRANSFERASE (NMNAT) EM Leishmania braziliensis

    Scientific Electronic Library Online (English)

    Jesús D, Castaño; Zuly J, Rivera; María H, Ramírez.

    2012-08-01

    Full Text Available Leishmania braziliensis é um parasita protozoário que causa a maioria dos casos de leishmaniose cutânea em pelo menos 15 países das Américas. A Organização Mundial de Saúde (OMS) informou que cerca de 12 milhões de pessoas estão infectadas em todo o mundo e esse número aumenta a cada ano. Devido ao [...] delicado problema de saúde pública decorrentes da prevalência desta doença é necessário estudar o metabolismo do parasita. A este respeito temos estudado a proteína NMNAT deste parasita, que é uma enzima central no metabolismo de todos os organismos de estar envolvido na produção de NAD+, um importante cofator em reações redox de processos centrais de celulares metabolismo. No L. braziliensis NMNAT encontrou uma seqüencia de 43 aminoácidos no terminal N homologia com a proteína faltando host. Este estudo produziu anticorpos IgG específicos para esta seqüência, usando como peptídeos de antígeno contendo a seqüência mencionada. Os anticorpos obtidos mostraram um reconhecimento da NMNAT L. braziliensis recombinantes por meio de julgamento por western blot. Abstract in spanish Leishmania braziliensis es un parásito protozoario causante de la mayor parte de casos de leishmaniasis cutánea en al menos quince países del continente americano. La Organización Mundial de la Salud (OMS) ha reportado que cerca de doce millones de personas están infectadas en el mundo y que este nú [...] mero aumenta cada año. Debido al delicado problema de salud pública derivado de la prevalencia de esta enfermedad se hace necesario el estudio del metabolismo de este parásito. En tal sentido se ha estudiado la proteína NMNAT de este parásito, la cual es una enzima central del metabolismo de todos los organismos al estar encargada de la síntesis del NAD+, un importante cofactor en reacciones redox de procesos centrales del metabolismo celular. En la NMNAT de L. braziliensis se ha encontrado una secuencia de 44 aminoácidos en el extremo N-terminal carente de homología con la proteína del hospedero. En este estudio se produjeron anticuerpos IgG específicos contra esta secuencia, utilizando como antígenos péptidos que contuvieran la secuencia mencionada. Los anticuerpos obtenidos mostraron un reconocimiento de la NMNAT recombinante de L. braziliensis mediante ensayo por western blot. Abstract in english Leishmania braziliensis is a protozoan which is cause of the most of the cutaneous leishmaniasis cases in at least 15 countries from America. World Health Organization (WHO) has reported that around 12 millions of people are infected in the world and this number increase every year. Because of the d [...] elicate problem of public health due to the prevalence of this disease, it is necessary the metabolism study in this parasite. In this way has been studied NMNAT protein of the parasite, which is a central enzyme of the metabolism of all organisms, since it is in charge of synthesizing NAD+, an important cofactor in oxidation-reduction reactions of central processes in the cellular metabolism. In The NMNAT of L. has been found a 43 amino acids sequence in the N terminal, which does not have homology with the protein in the human host. In this study were produced IgG antibodies against this sequence, using like antigens peptides that had the mentioned sequence. The produced antibodies recognized the recombinant NMNAT of L. braziliensis through western blot assay.

  1. Características epidemiológicas da leishmaniose tegumentar americana em uma região endêmica do Estado da Bahia: III. Fauna flebotomínica Epidemiological characteristics of American tegumentary leishmaniasis in an endemic region of the State of Bahia: III. Phlebotomine fauna

    Directory of Open Access Journals (Sweden)

    Julio A. Vexenat

    1986-09-01

    Full Text Available A fauna flebotomínica da região de Três Braços, uma área endêmica de leishmaniose cutânea-mucosa localizada no sudeste do Estado da Bahia, na região cacaueira, é muito variada. Foram identificadas 30 espécies de Lutzomyia em 13.535 exemplares coletados entre os anos de 1976 e 1984. Lu. withmani foi a espécie altamente predominante no ambiente peridoméstico e no interior das residências, com percentuais de 99,0 e 97,5, respectivamente. Na floresta, as espécies predominantes foram Lu. ayrozai e Lu. yuilli, aparecendo Lu. whitmani com apenas 1,0% do total de exemplares examinados. Lu. flaviscutellata, vetor comprovado da Leishmania mexicana amazonensis, foi também coletada em baixos índices. Lu. wellcomei, vetor da L. braziliensis braziliensis na Serra dos Carajás, Pará, Brasil, não foi encontrada na região de Três Braços onde o parasito causando infecções humanas é predominantemente L. b. braziliensis. Embora não se tenha encontrado infecção natural por promastigotas em 1.832 fêmeas de diversas espécies examinadas, discute-se a possibilidade de Lu. whitmani ser um vetor da L.b. braziliensis na região, mantendo, provavelmente, a transmissão entre o cão e o homem.The phlebotomine fauna is highly varied in três Braços, an endemic area american cutaneous leishmaniasis, situated in the cacao growing region in the southeast of Bahia State, brazil. Thirty species of the Lutzomyia genus were identified in 13,535 spcecimens collected between 1976 and 1984. Lutzomyia whitmani was the dominant species accounting for 99% or flies in the periodomicile and 97.5% of those caught in homes. In the forest the predominant species were Lu. ayrozai and Lu. yulli. Lu whitmani accounted for only 1.0% of the specimens examined. Lu. flaviscutellata, the proven vector of Leishmania mexicana amazonensis, was also collected in small numbers, I.u. wellcomei, a known vector of L. braziliensis braziliensis in the Serra dos Carajás, Pará, Brazil was not encountered in the Três Braços region where the parasite causing human infections is usually L.b. braziliensis. Although we have not encountered a natural infection with leishmanial promastigotes in 1.832 females of the various species examined, we discuss the probability that Lu. whitmani is the vector of L.b braziliensis in the region mantaining transmission in dogs and man.

  2. Leishmania (Viannia braziliensis em cães naturalmente infectados Leishmania (Viannia braziliensis in naturally infected dogs

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    Maria de Fátima Madeira

    2003-10-01

    Full Text Available Foram estudados oito cães provenientes do Município de Maricá (RJ, com lesões sugestivas de leishmaniose tegumentar americana por métodos parasitológicos e sorológicos. Leishmania spp foi encontrada em seis cães através do cultivo in vitro. Anticorpos específicos foram detectados em seis animais pelo ELISA e em dois pela imunofluorescência indireta. Cinco isolados caninos analisados apresentaram zimodema similar a Leishmania (Viannia braziliensis. Sugere-se que cães clinicamente suspeitos sejam acompanhados periodicamente, na tentativa de confirmar o diagnóstico da leishmaniose tegumentar canina.Eight dogs from Maricá Municipality (RJ, with suggestive lesion of american tegumentary leishmaniasis were studied by parasitological and serological methods. Leishmania spp was found in six dogs by in vitro cultivation. Specific antibodies were detected in six dogs by ELISA and in two by indirect immunofluorescence. Five canine isolates were found to belong to the same zymodeme as Leishmania (Viannia braziliensis. The authors suggest that clinically suspect dogs should be followed-up in an attempt to confirm the diagnostic of canine tegumentary leishmaniasis.

  3. Genomic Organization of Leishmania Species

    Directory of Open Access Journals (Sweden)

    B Kazemi

    2011-09-01

    Full Text Available Leishmania is a protozoan parasite belonging to the family Trypanosomatidae, which is found among 88 different countries. The parasite lives as an amastigote in vertebrate macro­phages and as a promastigote in the digestive tract of sand fly. It can be cultured in the laboratory us­ing appropriate culture media. Although the sexual cycle of Leishmania has not been observed during the promastigote and amastigote stages, it has been reported by some researchers. Leishma­nia has eukaryotic cell organization. Cell culture is convenient and cost effective, and because posttranslational modifications are common processes in the cultured cells, the cells are used as hosts for preparing eukaryotic recombinant proteins for research. Several transcripts of rDNA in the Leishmania genome are suitable regions for conducting gene transfer. Old World Leishmania spp. has 36 chromosomes, while New World Leishmania spp. has 34 or 35 chromo­somes. The genomic organization and parasitic characteristics have been investigated. Leishmania spp. has a unique genomic organization among eukaryotes; the genes do not have introns, and the chromosomes are smaller with larger numbers of genes confined to a smaller space within the nucleus. Leishmania spp. genes are organized on one or both DNA strands and are transcribed as polycistronic (prokaryotic-like transcripts from undefined promoters. Regulation of gene expres­sion in the members of Trypanosomatidae differs from that in other eukaryotes. The trans-splic­ing phenomenon is a necessary step for mRNA processing in lower eukaryotes and is observed in Leishmania spp. Another particular feature of RNA editing in Leishmania spp. is that mitochon­drial genes encoding respiratory enzymes are edited and transcribed. This review will discuss the chromosomal and mitochondrial (kinetoplast genomes of Leishmania spp. as well as the phenome­non of RNA editing in the kinetoplast genome.

  4. Combinations of ascaridole, carvacrol, and caryophyllene oxide against Leishmania.

    Science.gov (United States)

    Pastor, Jacinta; García, Marley; Steinbauer, Silvia; Setzer, William N; Scull, Ramón; Gille, Lars; Monzote, Lianet

    2015-05-01

    To date there are no vaccines against Leishmania and chemotherapy remains the mainstay for the control of leishmaniasis. The drugs currently used for leishmaniasis therapy are significantly toxic, expensive, and result in a growing frequency of refractory infections. In this study, we evaluated the effect of combinations of the main components of essential oil from Chenopodium ambrosioides (ascaridole, carvacrol, and caryophyllene oxide) against Leishmaniaamazonensis. Anti-leishmanial effects of combinations of pure compounds were evaluated in vitro and the fractional inhibitory concentration (FIC) indices were calculated. BALB/c mice infected with L. amazonensis were treated with different concentrations of ascaridole-carvacrol combinations by intralesional doses every 4 days. Disease progression and parasite burden in infected tissues were determined. In vitro experiments showed a synergistic effect of the combination of ascaridole-carvacrol against promastigotes of Leishmania with a FIC index of 0.171, while indifferent activities were observed for ascaridole-caryophyllene oxide (FIC index=3.613) and carvacrol-caryophyllene oxide (FIC index=2.356) combinations. The fixed ratio method showed that a 1:4 ascaridole-carvacrol ratio produced a better anti-protozoal activity on promastigotes, lower cytotoxicity, and synergistic activity on intracellular amastigotes (FIC index=0.416). Significant differences (panimals. Carvacrol showed significant higher anti-radical activity in the DPPH assay compared with caryophyllene oxide. Electron spin resonance spectroscopy in combination with spin trapping suggested the presence of carbon-centered radicals after activation of ascaridole by Fe(2+). The intensity of the signals is preferably decreased upon addition of carvacrol. The ascaridole-carvacrol combination could represent a future alternative to monotherapeutic anti-leishmanial agents. PMID:25697866

  5. Leishmania (Leishmania) hertigi in a porcupine (Coendou sp.) found in Brasília, Federal District, Brazil / Leishmania (Leishmania) hertigi em porco-espinho (Coendou sp.) encontrado em Brasília, Distrito Federal, Brasil

    Scientific Electronic Library Online (English)

    Denise Amaro da, Silva; Maria de Fatima, Madeira; Carlos Jose Lima, Barbosa Filho; Edvar Yuri Paheco, Schubach; Juliana Helena da Silva, Barros; Fabiano Borges, Figueiredo.

    2013-06-01

    Full Text Available Alguns estudos relatam o encontro de Leishmania (Leishmania) hertigi em estados da região Norte do Brasil. Na presente investigação, os autores descrevem o isolamento de Leishmania (Leishmania) hertigi em um porco-espinho (Coendou sp.) encontrado em Brasília, Distrito Federal, região Centro-oeste do [...] Brasil. Durante um estudo de leishmaniose visceral canina conduzido na cidade de Brasília, Distrito Federal, um porco-espinho foi encontrado morto em via pública. O animal foi identificado e fragmentos de pele íntegra e baço foram coletados para isolamento do parasito em cultura. Esse relato da ocorrência de L. hertigi em outra região do Brasil pode contribuir para evidenciar a distribuição desse parasita no país. Vale ressaltar a necessidade de estudos para compreensão do papel L. hertigi na patologia e patogênese da leishmaniose e a sua sobrevivência em mamíferos e possíveis vetores. Abstract in english Studies report the occurrence of Leishmania (Leishmania) hertigi in northern states of Brazil. In the present investigation, we describe the isolation of L. (L.) hertigi from a porcupine (Coendou sp.) found in Brasília, Federal District, center-west region of Brazil. During a study on canine viscera [...] l leishmaniasis conducted in the city of Brasília, Federal District, a porcupine was found dead on a public road. The animal was identified and fragments of intact skin and spleen were collected for isolation of parasite in the culture. This report of the occurrence of L. hertigi in another part of Brazil may help establish the distribution of this parasite in the country. Further studies are needed to better understand the role of L. hertigi in the pathology and pathogenesis of leishmaniasis and its survival in mammals and possible vectors.

  6. Heterorhabditis amazonensis RSC5 (Rhabditida: Heterorhabditidae) movement and host recognition / Desplazamiento y capacidad de búsqueda del nematodo entomopatógeno nativo Heterorhabditis amazonensis RSC5 (Rhabditida: Heterorhabditida)

    Scientific Electronic Library Online (English)

    VANESSA, ANDALÓ; GRAZIELLE, FURTADO MOREIRA; ALCIDES, MOINO JUNIOR.

    2014-06-01

    Full Text Available La respuesta de Heterorhabditis amazonensis RSC5 en comparación con otras especies de nematodos entomopatógenos como Steinernema carpocapsae All y Steinernema riobrave 355, a los compuestos liberados por diferentes hospederos (Galleria mellonella, Mycotretus apicalis y Tenebrio molitor) y su nivel d [...] e virulencia a estos insectos fue evaluada. Las pruebas se realizaron en placas de Petri con agar-agua 2% para determinar el movimiento de los nematodos con y sin posibilidad de escogencia por diferentes hospederos. Se cuantificó la proximidad de juveniles infectivos (JIs) al hospedero como una fuente de atracción. Con el fin de determinar el desplazamiento de JIs en una condición similar al suelo, un ensayo se llevó a cabo en un área con arena. Los nematodos fueron virulentos para los hospederos. Cuando los nematodos e insectos fueron puestos en agar-agua, JIs se movieron hacia el estímulo, con preferencia de H. amazonensis a ciertos insectos. En la arena, S. carpocapsae causó menor mortalidad (70% ± 8,9 para G. mellonella) que H. amazonensis y S. riobrave (80% ± 6,5 y 99% ± 0,0). Heterorhabditis amazonensis fue capaz de encontrar y elegir a sus hospederos (G. mellonella y T. molitor) similar al comportamiento de S. riobrave y localizar sus hospederos con más eficacia que S. carpocapsae. De este modo, la virulencia de H. amazonensis fue similar a S. riobrave y esta característica podría ser promisoria para introducir esta especie nativa en programas de manejo integrado de plagas. Abstract in english Response of Heterorhabditis amazonensis RSC5 to compounds released by different host insects and its virulence level to several insect hosts like Galleria mellonella, Mycotretus apicalis and Tenebrio molitor were evaluated in this study, and compared with other entomopathogenic nematode species like [...] Steinernema carpocapsae All and Steinernema riobrave 355. Tests were performed in Petri dishes with agar-water 2% to determine nematode movement toward the insect with and without opportunity of choosing different insect hosts. Evaluations were made quantifying the proximity of infective juveniles (IJs) to the insect as a source of allurement. In order to determine the displacement of IJs in a closed soil condition, a test was carried out in an arena with sand. The nematode was virulent to the target insects. When nematode and insect were released on agar-water, IJs moved toward the stimulus, with H. amazonensis howing preference for certain insects. In the arena with sand S. carpocapsae caused lower insect mortality (70% ± 8.9 for G. mellonella) than H. amazonensis and S. riobrave (80% ± 6.5 and 99% ± 0.0). Heterorhabditis amazonensis was able to find and choose its hosts (G. mellonella and T. molitor), similarly to S. riobrave behavior, and located them more effectively than S. carpocapsae. The virulence of H. amazonensis was thus similar to S. riobrave, and this characteristic could be promising to introduce this native species in integrated pest management programs.

  7. Global gene expression in Leishmania.

    Science.gov (United States)

    Cohen-Freue, Gabriela; Holzer, Timothy R; Forney, James D; McMaster, W Robert

    2007-08-01

    The completion of the genomic sequences of many protozoan pathogens of humans, including species of Leishmania, Trypanosoma and Plasmodium, provide new approaches to study the pattern of gene expression during differentiation and development. Leishmania are a major public health risk in many countries and cause a wide spectrum of clinical disease referred to as leishmaniasis. The Leishmania life cycle consists of two morphologically distinct stages: intracellular amastigotes that reside in the phagolysosome of mammalian macrophages, and extracellular promastigotes that reside within the gut of the sandfly vector. DNA microarray analysis is a powerful method to study global gene expression in terms of quantitation of mRNA levels. This review discusses the application of DNA microarray technology to study the pattern of global gene expression of Leishmania promastigote and amastigote life stages. Results from several studies show that, overall, there is a surprisingly low level of differentially expressed genes, ranging from 0.2% to 5% of total genes, between the amastigote and promastigote life stages. Thus, the Leishmania genome can be considered to be constitutively expressed with a limited number of genes showing stage-specific expression. Comparative genomic analyses of gene expression levels between Leishmania major and Leishmania mexicana show that the majority of differentially expressed genes between amastigotes and promastigotes are species specific with relatively few differentially expressed genes in common between these two Leishmania species. Quantitative proteomic analysis of Leishmania relative protein expression shows there is a weak correlation to gene expression. Therefore, Leishmania protein expression levels are likely regulated at the level of translation or by post transcriptional mechanisms, and differential protein modifications may be more important in development than the regulation of gene expression. PMID:17574557

  8. Miocardite crônica em um cão naturalmente infectado com Leishmania (Leishmania) infantum chagasi: aspectos clínicos e patológicos / Chronic myocarditis in a dog naturally infected by Leishmania (Leishmania) infantum chagasi: clinical and pathological aspects

    Scientific Electronic Library Online (English)

    R.S., Mendes; T.A., Gurjão; L.M., Oliveira; V.L., Santana; W.L., Tafuri; J.R.S., Santos; A.F.M., Dantas; A.P., Souza.

    2014-02-01

    Full Text Available A leishmaniose visceral (LV) é uma doença infecciosa crônica frequentemente fatal causada pela Leishmania infantum chagasi nas Américas. A enfermidade pode acometer vários órgãos, determinando diferentes manifestações clínicas. Contudo o envolvimento do coração raramente tem sido reportado em cães i [...] nfectados por Leishmania sp. Dessa forma, descreve-se um caso de miocardite crônica com repercussões clínicas e patológicas em um cão naturalmente infectado por Leishmania infantum chagasi. A positividade para Leishmaniose Visceral foi determinada pela presença de anticorpos antiLeishmania sp. nos testes sorológicos (RIFI, ELISA e DPP) e confirmada por visualização de formas amastigotas de Leishmania sp. em punção aspirativa do linfonodo poplíteo. O exame cardiovascular revelou alterações radiográficas, eletrocardiográficas, na pressão arterial e nos biomarcardores cardíacos. Após eutanásia, amostras de tecido cardíaco foram avaliadas histologicamente e submetidas à imunomarcação, onde foi observado infiltrado mononuclear (plasmo-histiolinfocitário), com presença de estruturas arredondadas de coloracão marrom-amareladas (imunomarcadas), indicando formas amastigotas de Leishmania infantum chagasi no miocárdio. Os aspectos etiopatogênicos da leishmaniose visceral sobre o miocárdio neste caso podem estar relacionados tanto à presença do parasita quanto à resposta "reacional inespecífica" do tecido à agressão do parasita no organismo. Todavia ainda não se sabem se as cepas de Leishmania infantum chagasi da região semiárida paraibana apresentam algum tropismo por tecido cardíaco ou se induzem a reação imunológica cruzada, com implicações clínicas. Abstract in english Visceral leishmaniasis (VL) is a chronic, often fatal infectious disease caused by Leishmania infantum chagasi in the Americas. The disease can affect many organs and may express different clinical forms. However, the involvement of the heart has rarely been reported in dogs infected by Leishmania s [...] p. Thus, we describe a case of chronic myocarditis with clinical and pathological effects in a dog naturally infected by Leishmania infantum chagasi. Positivity for Visceral Leishmaniasis was determined by the presence of anti-Leishmania sp. in serological tests (IFAT, ELISA and DPP) and confirmed by visualization of amastigote forms of the parasite in the popliteal lymph node aspiration samples. The cardiovascular clinical examination showed changes in the radiographic, ECG, blood pressure and heart biomarkers. After euthanasia, heart tissue samples were histologically examined and underwent our immunohistochemistry assessment, where mononuclear infiltrate was observed (plasma cells, lymphocytes and macrophages) with the presence of rounded brownish-yellow (immunomarked) cells, indicating amastigotes of Leishmania infantum chagasi within the myocardium. The etiopathogenic aspects of visceral leishmaniasis in the myocardium in this case may be related either to the presence of the parasite or the "nonspecific reactive" response of the tissue attributable to the aggression of the parasite in the body. However, it is not known if the strains of Leishmania infantum chagasi found in the semi-arid of Paraíba have some tropism for cardiac tissue or if they induce immunological cross-reaction with clinical implications.

  9. Características clínicas da leishmaniose tegumentar em crianças de 0 a 5 anos em uma área endêmica de Leishmania (Viannia braziliensis Clinical findings of tegumentary leishmaniasis in children under five years of age in an endemic area of Leishmania (Viannia braziliensis

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    Julia Ampuero

    2006-02-01

    Full Text Available Para caracterizar a clínica da leishmaniose tegumentar em crianças de 0 a 5 anos de idade, foram avaliadas, retrospectivamente, 4.464 fichas clínicas do Centro de Saúde de Corte de Pedra, Presidente Tancredo Neves, Bahia, Brasil, área endêmica de leishmaniose tegumentar americana, entre maio de 1987 e dezembro de 1995. Foram registrados neste período 4.275 casos novos de leishmaniose, dos quais, 491 (11,5% correspondiam a crianças de 0 a 5 anos. A razão entre gênero masculino e feminino nas crianças foi 1,1:1. A forma clínica predominante foi a cutânea (98% e as lesões ulceradas foram as mais freqüentes (99%. A localização das lesões ocorreu, principalmente, acima da cintura (pA retrospective study was performed in a field clinic to characterize the clinical findings of tegumentary leishmaniasis in children from 0 to 5 years old. The clinical records of 4,464 patients were analyzed at the Primary Health Center of Corte de Pedra, Presidente Tancredo Neves, Bahia, Brazil, from May 1987 to December 1995. Four hundred and ninety one (11.8% children were identified among 4,275 new cases of tegumentary leishmaniasis registered at this Unit. The gender ratio (M:F for children under six years was 1.1:1. Cutaneous lesions predominated (98%, mainly skin ulcers (99% located above the waist (p<0.05. Thirty five percent had multiple lesions. The observed magnitude of the disease in children, the similar proportion of cases in both genders and the location of the lesions suggest the possibility of peri or intradomiciliary transmission.

  10. Folate metabolic pathways in Leishmania

    OpenAIRE

    Vickers, Tim J.; Beverley, Stephen M.

    2011-01-01

    Trypanosomatid parasitic protozoans of the genus Leishmania are autotrophic for both folate and unconjugated pteridines. Leishmania salvage these metabolites from their mammalian hosts and insect vectors through multiple transporters. Within the parasite, folates are reduced by a bifunctional DHFR (dihydrofolate reductase)-TS (thymidylate synthase) and by a novel PTR1 (pteridine reductase 1), which reduces both folates and unconjugated pteridines. PTR1 can act as a metabolic bypass of DHFR in...

  11. Ocular alterations in dogs naturally infected by Leishmania (Leishmania chagasi Alterações oculares em cães infectados naturalmente por Leishmania (Leishmania chagasi

    Directory of Open Access Journals (Sweden)

    F.L.C. Brito

    2006-10-01

    Full Text Available Ocular conditions, anti-Leishmania antibodies and total protein of the aqueous humor were studied in dogs naturally infected by Leishmania (Leishmania chagasi. Fifty dogs were analyzed and assigned into two groups of 25 animals each. All animals were submitted to routine ophthalmic exam. Results showed that 76% of the affected animals presented ocular signs, being uveitis the predominant. The mean of total protein in the aqueous humor of animals with uveitis was higher (PEstudaram-se as condições oculares, os anticorpos anti-Leishmania e os valores de proteína total no humor aquoso de cães infectados naturalmente por Leishmania (Leishmania chagasi. Analisaram-se 50 cães, divididos em dois grupos de 25 animais. Todos os animais foram submetidos a exame oftálmico rotineiro. Os resultados mostraram que 76% dos cães infectados apresentaram sinais oculares, sendo a uveíte a alteração predominante. A média de proteína total no humor aquoso dos animais com uveíte foi maior (P<0,05, que a dos animais com outros sinais oculares ou sem qualquer sinal. Os valores de anticorpos anti-L. chagasi obtidos no plasma foram estatisticamente superiores aos encontrados no humor aquoso (P<0,05.

  12. Xiphidorus amazonensis n. sp. (Nematoda: Longidoridae) from the Brazilian Amazon Basin

    OpenAIRE

    Uesugi, C.H.; C. S. Huang; Cares, J. E.

    1985-01-01

    Xiphidorus amazonensis n. sp. was found in the rhizospheres of Jatropha curcas, Musa sp., Anona muricata, Cassia tora, Panicum laxum, Paspalum fasciculatum, Aeschynomene sensitiva, Saccharum officinarum, Manihot esculenta, Abelmoschus esculentus, Tamarindus indica, Mangifera indica, Vigna unguiculata, Zea mays, Commelina sp., Cyperus rotundus, Fimbristylis miliacea, Citrus sinensis, and Eichhornia crassipes on the Amazon River island of Xiborena, approximately 40 km southeast of Manaus, capit...

  13. Reacción de antígenos de Leishmania (Leishmania) mexicana con sueros de pacientes con leishmaniosis cutánea de Sinaloa, México / Reaction of Leishmania (Leishmania) mexicana antigens by sera of patients with cutaneous leishmaniasis from Sinaloa, Mexico

    Scientific Electronic Library Online (English)

    Patricia Guadalupe, Salazar-Mejía; Celia Rosa, Tejeda-Aguirre; Héctor Samuel, López-Moreno.

    2010-04-01

    Full Text Available OBJETIVO: Detectar los antígenos de Leishmania (Leishmania) mexicana que reaccionan con sueros de pacientes con leishmaniosis cutánea (LC) de Sinaloa, México. MATERIAL Y MÉTODOS: Un extracto crudo de L. (L.) mexicana fue usado como antígeno para Western blots 2-D empleando sueros de cinco pacientes [...] con LC y controles originarios de Sinaloa, México, durante el 2008. RESULTADOS: Cinco antígenos fueron detectados sólo por los sueros de los cinco pacientes estudiados; estos son: 26 kDa (pI 7.8), 27 kDa (pI 8.1), 28 kDa (pI 8.6), 29 kDa (pI 8.5) y 31 kDa (pI 9.0). CONCLUSIONES: Se detectaron nuevos antígenos de L. (L.) mexicana potencialmente inmunodominantes, lo que sugiere a este parásito como el agente causal de la LC en Sinaloa. Abstract in english OBJECTIVE: To detect Leishmania mexicana antigens reacting with sera of patients with cutaneous leishmaniasis (CL). MATERIAL AND METHODS: A crude extract of L. mexicana was used as antigen for 2-D Western blot using sera from 5 patients with CL and controls from Sinaloa, Mexico during 2008. RESULTS: [...] Five antigens were detected in the five infected patients analyzed; their molecular weights and isoelectric points were: 26 kDa (pI 7.8), 27 kDa (pI 8.1), 28 kDa (pI 8.6), 29 kDa (pI 8.5) and 31 kDa (pI 9.0). CONCLUSION: New potentially immunodominant L. mexicana antigens were detected, suggesting that this parasite could be the species responsible for human infection in Sinaloa.

  14. Prostaglandin production from arachidonic acid and evidence for a 9,11-endoperoxide prostaglandin H2 reductase in Leishmania.

    Science.gov (United States)

    Kabututu, Zakayi; Martin, Samuel K; Nozaki, Tomoyoshi; Kawazu, Shin-ichiro; Okada, Tetsuya; Munday, Craig Joe; Duszenko, Michael; Lazarus, Michael; Thuita, Lucy W; Urade, Yoshihiro; Kubata, Bruno Kilunga

    2002-12-19

    Lysates of Leishmania promastigotes can metabolise arachidonic acid to prostaglandins. Prostaglandin production was heat sensitive and not inhibited by aspirin or indomethacin. We cloned and sequenced the cDNA of Leishmania major, Leishmania donovani, and Leishmania tropica prostaglandin F(2alpha) synthase, and overexpressed their respective 34-kDa recombinant proteins that catalyse the reduction of 9,11-endoperoxide PGH(2) to PGF(2alpha). Database search and sequence alignment alignment showed that L. major prostaglandin F(2alpha) synthase exhibits 61, 99.3, and 99.3% identity with Trypanosoma brucei, L. donovani, and L. tropica prostaglandin F(2alpha) synthase, respectively. Using polymerase chain reaction amplification, Western blotting, and immunofluorescence, we have demonstrated that prostaglandin F(2alpha) synthase protein and gene are present in Old World and absent in New World Leishmania, and that this protein is localised to the promastigote cytosol. PMID:12464415

  15. Ocorrência de Leishmania spp. em felinos do município de Araçatuba, SP Occurrence de Leishmania spp. in domestic cats from Araçatuba, SP

    Directory of Open Access Journals (Sweden)

    Katia Denise Saraiva Bresciani

    2010-06-01

    Full Text Available Este trabalho teve como objetivo comparar a ocorrência de Leishmania spp. em gatos por dois métodos (citológico e sorológico, bem como associar a ocorrência deste protozoário com as variáveis sexo, idade e raça. Amostras séricas de 283 felinos domésticos foram testadas pela Reação de Imunofluorescência Indireta (RIFI, e o exame parasitológico direto de linfonodos também foi realizado para a verificação da positividade para Leishmania spp. Ocorrência de 0,7% (2/283 foi observada nos felinos examinados, por meio de imprint de linfonodos e nenhum animal apresentou títulos de anticorpos para Leishmania spp. As duas fêmeas positivas eram sem raça definida, sendo uma jovem e outra adulta. Por meio dos resultados obtidos, não foi constatada diferença estatisticamente significante em relação às variáveis sexo, raça e idade nos gatos desta pesquisa (p > 0,05. Ocorrência de Leishmania spp. nos gatos deste estudo foi baixa. Devido a esta baixa incidência sugere-se que estes não assumem importância epidemiológica na área do estudo.This study had the purpose to compare the occurrence of Leishmania spp. in felines through two methods (cytological and serological, as well as to associate the occurrence of this protozoan with the sex, age and breed variables. Serum samples from 283 domestic felines were processed by means of Indirect Immunofluorescence Reaction (IIR, and the direct parasitological test for linfonodes was also carried out in order to verify positivity for Leishmania spp. Occurrence of 0.7% (2/283 was observed in the tested felines by means of linfonode imprinting and no animal showed title of antibodies for Leishmania spp. The two positive females were mongrel, a young female and an adult female feline. From the obtained results, no statistically significant difference was observed as regards the sex, breed and age variables in this research (p > 0.05. Occurrence of Leishmania spp. in the cats of this study was low. Such low incidence suggests that these hosts has no epidemiological relevance in the study area.

  16. Caracterización de dos proteínas metacíclicas de leishmania y su relación con la virulencia

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    Christof Berberich

    2000-02-01

    Full Text Available

    Los parásitos de Leishmania durante su crecimiento tanto in vivo como in vitro se diferencian desde un estado no infectivo o poco infectivo hasta uno más infectivo. Este proceso de diferenciación está acompañado de cambios en la expresión de algunas moléculas. Entre las moléculas mejor estudiadas que experimentan modificaciones tanto cualitativas como cuantitativas en la expresión, durante este proceso de diferenciación, se encuentra un glicoconjugado de superficie denominado Lipofosfoglicano (Turco y Descoteaux, 1992 y una glicoproteína de superficie con actividad proteasa, denominada gp63 (Kweider, et al.1987. Posteriormente, empleando técnicas de hibridización substractiva, se han identificado los genes, Meta-1 (Nourbakhsh, et al., 1996 y Mat-1 (Brodin et al., 1992 los cuales se expresan preferencialmente o exclusivamente en el promastigote metacíclico infectivo. Poco se conoce sobre la función de estos dos genes en el ciclo de vida de Leishmania. Experimentos de gene-knockout para tratar de elucidar un posible papel del gen Meta-1 mostraron que no puede ser reemplazado dado que los dobles mutantes no fueron viables, sugiriendo el papel esencial de esta proteína, en promastigotes. Sin embargo, sobreexpresión de la proteína Meta-1 en promastigotes de L. amazonensis generó parásitos mas virulentos que los parásitos silvestres (Uliana et al., 1999.

    En este estudio se describe la caracterización molecular de estos dos genes metacíclicos en Leishmania infantum. Además, se evaluará el papel de la proteína Meta-1 en la virulencia de Leishmania empleando la técnica de RNA antisentido. Para esto se clonará en orientación reversa el ORF de meta-1 junto con el 3’ UTR, amplificados por PCR a partir de un clon cósmido aislado de una librería de DNA genómico de L. infantum. Esta técnica ha sido empleada en Leishmania para evaluar función génica con buenos resultados (Chen, et al., 2000.

  17. The expression of HSP83 genes in Leishmania infantum is affected by temperature and by stage-differentiation and is regulated at the levels of mRNA stability and translation

    Directory of Open Access Journals (Sweden)

    Abanades Daniel R

    2004-06-01

    Full Text Available Abstract Background Exposure of Leishmania promastigotes to the temperature of their mammalian hosts results in the induction of a typical heat shock response. It has been suggested that heat shock proteins play an important role in parasite survival and differentiation. Results Here we report the studies on the expression of the heat shock protein 83 (HSP83 genes of Leishmania infantum. Confirming previous observations for other Leishmania species, we found that the L. infantum HSP83 transcripts also show a temperature-dependent accumulation that is controlled by a post-transcriptional mechanism involving sequences located in the 3'-untranslated region (3'-UTR. However, contrary to that described for L. amazonensis, the accumulation of the HSP83 transcripts in L. infantum is dependent on active protein synthesis. The translation of HSP83 transcripts is enhanced during heat shock and, as first described in L. amazonensis, we show that the 3'-UTR of the L. infantum HSP83 gene is essential for this translational control. Measurement of the steady-state levels of HSP83 transcripts along the promastigote-to-amastigote differentiation evidenced a specific profile of HSP83 RNAs: after an initial accumulation of HSP83 transcripts observed short after (2 h incubation in the differentiation conditions, the amount of HSP83 RNA decreased to a steady-state level lower than in undifferentiated promastigotes. We show that this transient accumulation is linked to the presence of the 3'-UTR and flanking regions. Again, an 8-fold increase in translation of the HSP83 transcripts is observed short after the initiation of the axenic differentiation, but it is not sustained after 9 h. Conclusions This transient expression of HSP83 genes could be relevant for the differentiation of Leishmania, and the underlying regulatory mechanism may be part of the developmental program of this parasite.

  18. Movement of Heterorhabditis amazonensis and Steinernema arenarium in search of corn fall armyworm larvae in artificial conditions

    Scientific Electronic Library Online (English)

    Vanessa, Andaló; Viviane, Santos; Grazielle F., Moreira; Camila, Moreira; Marcela, Freire; Alcides, Moino Jr..

    2012-06-01

    Full Text Available Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) is considered to be the main pest of maize crops in Brazil. Entomopathogenic nematodes (EPN) may be used to control this pest and exhibit different, unique abilities to search for their hosts. The movement of EPN in relation to S. frugiper [...] da was evaluated. To test for horizontal movement, a styrofoam enclosure filled with sand was divided into segments, nematodes were placed at the entrance to the enclosure and a larva was placed at the end of each division. The same approach was used to evaluate vertical movement; however, PVC pipes were used in this case. In general, the mortality was inversely proportional to the initial distance between host and nematodes. In the vertical displacement test, both nematodes were able to kill the larvae up to a distance of 25 cm. Therefore, the infective juveniles of H. amazonensis and S. arenarium can search out, infect and kill larvae of S. frugiperda at distances of up to 60 cm and 25 cm of horizontal and vertical displacement, respectively.

  19. First occurrence of an autochthonous canine case of Leishmania (Leishmania infantum chagasi in the municipality of Campinas, State of São Paulo, Brazil Ocorrência do primeiro caso autóctone canino por Leishmania (Leishmania infantum chagasi no Município de Campinas, Estado de São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Elisa San Martin Mouriz Savani

    2011-08-01

    Full Text Available An autochthonous case of visceral leishmaniasis is reported in a dog (Canis familiaris as an apparently natural infection in a non-endemic area. DNA obtained from spleen and liver samples produced the expected fragment in a Leishmania-specific rDNA-based nested-PCR assay. The PCR product, a 490 bp fragment, was sequenced and the nucleotide sequence was identical to that of Leishmania (Leishmania infantum chagasi. These results are surprising since no autochthonous human or canine cases of visceral leishmaniasis have ever been reported in this municipality. This case suggests that natural transmission of this disease is occurring in this area.Caso autóctone de leishmaniose visceral é relatado em cão (Canis familiaris, aparentemente em área não endêmica. DNA obtido a partir de amostras do baço e fígado foram submetidos a nested-PCR baseada no rDNA específico de Leishmania. Os produtos das PCR foram sequenciados e os 490 pares de base foram idênticos a Leishmania (Leishmania infantum chagasi. Esses resultados são surpreendentes, uma vez que, nenhum caso autóctone canino ou humano de leishmaniose visceral havia sido relatado neste município. Esse caso sugere que a transmissão natural da doença está ocorrendo nesta área.

  20. First occurrence of an autochthonous canine case of Leishmania (Leishmania) infantum chagasi in the municipality of Campinas, State of São Paulo, Brazil / Ocorrência do primeiro caso autóctone canino por Leishmania (Leishmania) infantum chagasi no Município de Campinas, Estado de São Paulo, Brasil

    Scientific Electronic Library Online (English)

    Elisa San Martin Mouriz, Savani; Douglas, Presotto; Thais, Roberto; Maria Cecília Gibrail de Oliveira, Camargo; Sandra Regina Nicoletti, D' auria; Débora Veiga, Sacramento.

    2011-08-01

    Full Text Available Caso autóctone de leishmaniose visceral é relatado em cão (Canis familiaris), aparentemente em área não endêmica. DNA obtido a partir de amostras do baço e fígado foram submetidos a nested-PCR baseada no rDNA específico de Leishmania. Os produtos das PCR foram sequenciados e os 490 pares de base for [...] am idênticos a Leishmania (Leishmania) infantum chagasi. Esses resultados são surpreendentes, uma vez que, nenhum caso autóctone canino ou humano de leishmaniose visceral havia sido relatado neste município. Esse caso sugere que a transmissão natural da doença está ocorrendo nesta área. Abstract in english An autochthonous case of visceral leishmaniasis is reported in a dog (Canis familiaris) as an apparently natural infection in a non-endemic area. DNA obtained from spleen and liver samples produced the expected fragment in a Leishmania-specific rDNA-based nested-PCR assay. The PCR product, a 490 bp [...] fragment, was sequenced and the nucleotide sequence was identical to that of Leishmania (Leishmania) infantum chagasi. These results are surprising since no autochthonous human or canine cases of visceral leishmaniasis have ever been reported in this municipality. This case suggests that natural transmission of this disease is occurring in this area.

  1. Western blot analysis as an aid for the diagnosis of cutaneous leishmaniasis due to Leishmania major.

    Science.gov (United States)

    Pomares, Christelle; Despierres, Laura; del Giudice, Pascal; Delaunay, Pascal; Michel, Grégory; Ferrua, Bernard; Marty, Pierre

    2012-07-01

    Cutaneous leishmaniasis (CL) due to Leishmania major is endemic in the Old World. To evaluate the diagnostic value of Western blot (WB) compared with IFAT, we tested serum samples from 45 patients with proven CL. Twenty-one (47%) patients were positive by IFAT and all patients were positive by WB with specific bands against 14kDa and/or 18kDa Leishmania antigens. Our results suggest that WB could be a useful non-invasive tool for the diagnosis of CL caused by L. major. PMID:22657532

  2. Revision of the genus Macrostomus Wiedemann (Diptera, Empididae, Empidinae). IV. The amazonensis species-group.

    Science.gov (United States)

    Rafael, José Albertino; Cumming, Jeffrey M

    2015-01-01

    Six new species of Macrostomus Wiedemann are described, namely M. acreanus sp. nov. from Brazil (Acre state), M. amazonensis sp. nov. from Guyana and Brazil (Roraima, Amazonas, Pará, Rondônia, and Mato Grosso states), M. albicaudatus sp. nov. from Brazil (Roraima, Amazonas, and Pará states), M. paraiba sp. nov. from Brazil (Paraíba state), M. trombetensis sp. nov. from Brazil (Pará state) and M. xavieri sp. nov. from Guyana and Brazil (Amazonas state). The six species are all treated in the M. amazonensis species-group, which is defined on the basis of one pair of ocellar setae and no supra-alar postsutural setae in combination with characters of the male and female terminalia. A key to the included species is presented and the geographical distributions of the species are mapped. PMID:25947722

  3. Infecção natural de Lutzomyia longipalpis por Leishmania sp. em Teresina, Piauí, Brasil Natural infection of Lutzomyia longipalpis by Leishmania sp. in Teresina, Piauí State, Brazil

    Directory of Open Access Journals (Sweden)

    Jackellyne Geórgia Dutra e Silva

    2007-07-01

    Full Text Available No Brasil, o controle do vetor Lutzomyia longipalpis é uma das principais estratégias utilizadas para limitar a expansão da leishmaniose visceral americana. Entretanto, poucos são os estudos sobre a infecção natural destes flebotomíneos por espécies de Leishmania. Um estudo sobre a infecção natural de Lu. longipalpis por Leishmania sp. foi realizado no bairro Bela Vista, Teresina, Piauí, um dos principais focos urbanos da leishmaniose visceral americana no Brasil. Entre fevereiro de 2004 e janeiro de 2005 realizaram-se 180 capturas usando-se armadilhas luminosas do tipo CDC. Foram dissecadas e examinadas, em média, dez fêmeas por captura para detecção de formas evolutivas de Leishmania sp., identificando-se 1.832 exemplares de Lu. longipalpis e seis de Lu. whitmani. Vinte (1,1% espécimes, todas de Lu. longipalpis, estavam infectadas com as formas procíclica e nectomonada de Leishmania sp., localizadas, principalmente, na porção posterior do trato digestivo. O maior percentual de insetos infectados foi encontrado quatro meses após o período de maior precipitação pluviométrica, sugerindo que variáveis climáticas podem contribuir para a predição não apenas da abundância destes dípteros, mas também do seu grau de infecção natural.In Brazil, control of the vector Lutzomyia longipalpis is one of the main strategies used to limit the expansion of American visceral leishmaniasis. However, studies on the ecology of this sand fly are rare, especially regarding its natural infection with species of Leishmania. A study of the natural infection of Lu. longipalpis by Leishmania sp. was carried out in the Bela Vista neighborhood in the city of Teresina, Piauí State, Brazil, an important area of American visceral leishmaniasis transmission. From February 2004 to January 2005, sand flies were captured with CDC light traps. Approximately 10 female sand flies in each capture were dissected and examined for the presence of evolutionary forms of Leishmania sp. Two sand fly species were identified: 1,832 were Lu. longipalpis and six Lu. whitmani. Twenty female sand flies (1.1%, all Lu. longipalpis, were infected with procyclic and nectomonad forms of Leishmania sp., found mostly in the hindgut. Higher proportions of infected sand flies were found four months after the rainy season, suggesting that environmental factors may predict not only vector abundance (as already known but also their level of infection.

  4. Interaction of avirulent Leishmania species with rat peritoneal macrophages

    Scientific Electronic Library Online (English)

    Trina, Bastardo; Lucila, Arcay-de-Peraza; Félix, Tejero.

    1983-03-01

    Full Text Available Um sistema "in vivo" foi desenvolvido para estudar-se o comportamento do parasito-célula hospedeiro em leshimaniose cutânea e visceral com promastigotos avirulentos de L. brasiliensis e L. donovani (mantidos no meio Davis) e com macrófagos de exsudado peritonial de rato. As espécies inicialmente for [...] am isoladas de casos humanos. A confrontação de Leishmania spp-macrófago se realizou na presença do meio 199 e a duas temperaturas diferentes, para L. brasiliensis 33ºC e para L donovani 37ºC. Apesar de o rato ser um animal resistente à infecção de Leishmania spp.; promastigotos das espécies por nos estudadas não só se interiorizaram mas também se diferenciaram em amastigotos com posterior multiplicação, a partir dos 10 minutos depois da infecção dos macrófagos e até as 24 horas. Abstract in english An "in vitro" system has been developed for study of host cell-parasite interaction in visceral and cutaneous leishmaniasis. Avirulent promastigotes of L. brasiliensis and L. donovani, from strains originally isolated from human cases and mantained by serial culture in Davis' Medium were allowed to [...] infect cultured macrophages from rat peritoneal exudate. Challenge of the macrophages by parasites took place in 199 medium, at 33ºC for L. brasiliensis and at 37ºC for L. donovani. Although the rat is resistant to infections by Leishmania spp., the promastigotes not only invaded the host cells, but transformed into amastigotes and later mutiplied, from 10 min after challenge to 24 hours later.

  5. Evolution and species discrimination according to the Leishmania heat-shock protein 20 gene.

    Science.gov (United States)

    Fraga, Jorge; Montalvo, Ana Margarita; Van der Auwera, Gert; Maes, Ilse; Dujardin, Jean-Claude; Requena, José M

    2013-08-01

    The Leishmania genus comprises up to 35 species, of which 20 are responsible for human disease. However, the taxonomic status for many of them is under discussion. The small Heat Shock Proteins (sHSPs) are physiologically relevant, protecting cellular proteins from aggregation and maintaining cellular viability under intensive stress conditions. In Leishmania, a protein of this class was previously described, the 20-kDa heat-shock protein (HSP20), which is encoded by a single gene. In the present study, we used this target, alone or in combination with hsp70 gene, to investigate the phylogenetic relationships among Leishmania species. Using a pair of degenerate primers it was possible amplifying a 370bp fragment of the hsp20 coding region in 39 strains of very different geographic origins, representing in total 16 Leishmania species (14 if L. chagasi and L. archibaldi are considered synonymous names of L. infantum and L. donovani, respectively). Nucleotide sequences were readily obtained by direct sequencing of the amplification products. Both phylogenetic trees and networks based on either hsp20 sequences or combined datasets of hsp20 and hsp70 sequences were constructed. These phylogenic analyses supported the division of the Leishmania genus into nine species: L. (L.) donovani, L. (L.) major, L. (L.) tropica, L. (L.) aethiopica, L. (L.) mexicana, L. (V.) lainsoni, L. (V.) naiffi, L. (V.) guyanensis and L. (V.) braziliensis. Additionally, by network analysis, the subspecies L. (L.) donovani infantum and L. (V.) braziliensis peruviana were recognized within the L. (L.) donovani and L. (V.) braziliensis species, respectively. Therefore, hsp20 gene was found to be a suitable molecular marker for Leishmania typing and classification purposes. In addition, this study represents a solid contribution to the objective of establishing a more reliable taxonomy for the genus Leishmania. PMID:23722022

  6. Evaluacion por Western Blot, Inmunofluorescencia Indirecta y ELISA de Perros Infectados con Leishmania (Leishmania infantum Western blot, ELISA and indirect immunofluorescence test evaluation of Leishmania (Leishmania infantum-infected dogs

    Directory of Open Access Journals (Sweden)

    Jimmy J Vargas-Duarte

    2009-08-01

    Full Text Available Objetivo Evaluar el desempeño de las pruebas empleadas en Colombia para el diagnóstico de la leishmaniasis visceral canina y adaptar una técnica de Western blot empleando animales experimental y naturalmente infectados. Metodología Se obtuvieron sueros de 10 perros infectados experimentalmente con L. infantum, 5 perros infectados naturalmente, 16 perros sanos, 26 de reacción cruzada (infectados con Babesia canis, Erhlichia canis, Dirofilaria immitis, Trypanosoma cruzi, Leishmania (Viannia spp., 40 de zonas no endémicas y 150 de zona endémica. Todos fueron evaluados mediante las pruebas de inmunofluorescencia indirecta (IFI, ELISA y Western blot (WB. Resultados Se encontró que IFI tuvo el mayor porcentaje de positividad en los perros infectados (73 % mientras que el menor porcentaje de falsos positivos se obtuvo por WB (2,5 %. La prueba de ELISA fue la menos eficiente. Fueron reconocidas 24 fracciones antigénicas, las bandas de 29, 34, 50, 69, 75, 86, 99 y 123 kDa fueron responsables de reacciones inespecíficas en los sueros de perros sanos, de zona no endémica y de reacción cruzada. Las bandas por debajo de 29 kDa mostraron ser potencialmente diagnósticas, especialmente la fracción de 13 kDa. Conclusiones Los métodos directos y serológicos pueden subdiagnosticar la infección por Leishmania, solamente un constructo que combine tanto pruebas directas como indirectas sería la forma más eficiente de diagnóstico.Objective Evaluating canine visceral leishmaniasis diagnostic test performance in Colombia and adapting the Western blot test in naturally and experimentally infected dogs. Methods Sera were obtained from 10 experimentally L. Infantum-infected dogs, 5 naturally infected dogs, 16 healthy dogs, 26 Babesia canis, Erhlichia canis, Dirofilaria immitis, Trypanosoma cruzi and Leishmania (Viannia spp infected dogs, 40 dogs from non-endemic areas and 150 from endemic areas. Sera were tested for L. infantum infection using immunofluorescent antibody (IFAT, ELISA and Western blot (WB tests. Results Positives results were obtained for 73 % of known infected dogs by the IFAT test and false positives were obtained for 2.5 % of non-infected dogs using WB. ELISA was not efficient for diagnosis. 24 antigenic fractions were recognised in tested sera using WB; however, 29, 34, 50, 69, 75, 86, 99 and 123 kDa bands were recognised in sera from dogs from non-endemic areas, healthy dogs and Trypanosoma cruzi, Erhlichia canis, Dirofilaria immitis and Babesia canis infected dogs. The 13 kDa fraction proved potentially useful for diagnosing canine visceral leishmaniasis. ConclusionsThe separate use of parasitological and serological test could lead to misdiagnosis of Leishmania infection; using both kinds of technique simultaneously is thus highly recommended.

  7. Ocorrência de Leishmania spp. em felinos do município de Araçatuba, SP / Occurrence de Leishmania spp. in domestic cats from Araçatuba, SP

    Scientific Electronic Library Online (English)

    Katia Denise Saraiva, Bresciani; Ana Claudia Marques, Serrano; Lucas Vinicius Shigaki de, Matos; Elisa San Martin Mouriz, Savani; Sandra Regina Nicoletti, D' Auria; Silvia Helena Venturoli, Perri; Fabio Luiz, Bonello; Willian Marinho Dourado, Coelho; Carolina Godoi, Aoki; Alvimar José da, Costa.

    2010-06-01

    Full Text Available Este trabalho teve como objetivo comparar a ocorrência de Leishmania spp. em gatos por dois métodos (citológico e sorológico), bem como associar a ocorrência deste protozoário com as variáveis sexo, idade e raça. Amostras séricas de 283 felinos domésticos foram testadas pela Reação de Imunofluorescê [...] ncia Indireta (RIFI), e o exame parasitológico direto de linfonodos também foi realizado para a verificação da positividade para Leishmania spp. Ocorrência de 0,7% (2/283) foi observada nos felinos examinados, por meio de imprint de linfonodos e nenhum animal apresentou títulos de anticorpos para Leishmania spp. As duas fêmeas positivas eram sem raça definida, sendo uma jovem e outra adulta. Por meio dos resultados obtidos, não foi constatada diferença estatisticamente significante em relação às variáveis sexo, raça e idade nos gatos desta pesquisa (p > 0,05). Ocorrência de Leishmania spp. nos gatos deste estudo foi baixa. Devido a esta baixa incidência sugere-se que estes não assumem importância epidemiológica na área do estudo. Abstract in english This study had the purpose to compare the occurrence of Leishmania spp. in felines through two methods (cytological and serological), as well as to associate the occurrence of this protozoan with the sex, age and breed variables. Serum samples from 283 domestic felines were processed by means of Ind [...] irect Immunofluorescence Reaction (IIR), and the direct parasitological test for linfonodes was also carried out in order to verify positivity for Leishmania spp. Occurrence of 0.7% (2/283) was observed in the tested felines by means of linfonode imprinting and no animal showed title of antibodies for Leishmania spp. The two positive females were mongrel, a young female and an adult female feline. From the obtained results, no statistically significant difference was observed as regards the sex, breed and age variables in this research (p > 0.05). Occurrence of Leishmania spp. in the cats of this study was low. Such low incidence suggests that these hosts has no epidemiological relevance in the study area.

  8. Fatty acid and hydrocarbon composition in tropical marine Shewanella amazonensis strain SB2B(T).

    Science.gov (United States)

    Motoigi, Taro; Okuyama, Hidetoshi

    2011-10-01

    Shewanella amazonensis strain SB2B(T) is an isolate from shallow-water marine sediments derived from the Amazon River delta. This bacterium contained a long-chain polyunsaturated hydrocarbon, all-cis -3,6,9,12,16,19,22,25,28 hentriacontanonaene (C31:9), constituting 1-2% of the total fatty acid methyl ester and hydrocarbon fraction, which was produced dependently of decreased growth temperature. Analysis of its cellular fatty acid composition demonstrated that isopentadecanoic acid was the major fatty acid component and that all the main monounsaturated fatty acids had straight chains with a cis configuration. However, monoenoic cyclopropyl fatty acids, which were previously reported to be present in this bacterium, were not detected by mass spectrometric analysis. The growth temperature affected the content of ?9-cis -hexadecenoic [16:1(?9c)], palmitic, and heptadecanoic acids. These results suggest that C31:9, as well as 16:1(?9c) might be involved in adaptation to low temperature in S. amazonensis strain SB2B(T) . Our result suggests that polyunsaturated fatty acid synthase protein complex may be involved in synthesis of C31:9 but not in production of eicosapentaenoic acid. PMID:21656813

  9. Anticorpos antipromastigotas vivas de Leishmania (Viannia braziliensis, detectados pela citometria de fluxo, para identificação da infecção ativa na leishmaniose tegumentar americana Anti-live Leishmania (Viannia braziliensis promastigote antibodies, detected by flow cytometry, to identify active infection in american cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Roberta Dias Rodrigues Rocha

    2002-12-01

    Full Text Available Neste estudo, descrevemos etapas iniciais de padronização de uma nova metodologia para detecção de anticorpos antipromastigotas vivas de Leishmania (Viannia braziliensis, pela citometria de fluxo e a análise de sua aplicabilidade para estudos clínicos. Foram avaliados 39 indivíduos com sorologia convencional (RIFI positiva para leishmaniose, classificados quanto à ausência/presença de lesão (L- e L+. Os resultados foram expressos sob a forma de percentual de parasitas fluorescentes positivos (PPFP. A análise dos dados, na diluição 1:1.024, permitiu distinguir 95% dos pacientes L+ como um grupo de alta reatividade (PPFP>50% e 72% dos indivíduos L- como um grupo de baixa reatividade (PPFPIn the current study we described initial standardization steps of a new methodology to detect anti-live Leishmania (Viannia braziliensis promastigote antibodies by flow cytometry, followed by analysis of its applicability to clinical studies. We have studied 39 individuals with positive conventional serology to leishmaniasis, classified according to the absence/presence of cutaneous lesions (L- and L+. The results were expressed as percentage of positive fluorescent parasites (PPFP. Data analysis at dilution of 1:1,024, allowed the distinction of 95% of L+ patients as a group of high reactivity (PPFP>50% and 72% of L- individuals as a group of low reactivity (PPFP<50%. The analysis of immunofluorescence assay titers did not show any relationship with the absence/presence of lesion. Together, our data support the applicability of flow cytometry to identify cases of active infection, which has not been possible through conventional serological reactions.

  10. Identificación de una secuencia de ADN genómico de Leishmania especifica del subgénero Leishmania / Identification of a genomic DNA sequence of Leishmania, specific of Leishmania subgenus

    Scientific Electronic Library Online (English)

    Andrea, Orué; Nancy Y, De Abreu; Clara, Martínez; Alexis, Mendoza-León.

    2008-06-01

    Full Text Available Leishmania es el agente causante de la compleja enfermedad conocida como leishmaniasis. Las distintas especies de este parásito protozoario se encuentran agrupadas en dos subgéneros, Viannia y Leishmania, de acuerdo a su desarrollo en el mosquito vector. Un ensayo de PCR, ?500-PCR, específico del su [...] bgénero Viannia, ha sido desarrollado utilizando la secuencia de ADN genómico denominada ?500. En este trabajo se presenta el aislamiento e identificación de una secuencia genómica de 280 pb, L280, a partir del ADN genómico de Leishmania (Leishmania) mexicana luego de aplicar el ensayo ?500-PCR en condiciones de baja rigurosidad. La secuenciación parcial de L280 permitió diseñar un ensayo de PCR (L280-PCR) que generó un producto de amplificación de 260 pb, en distintas condiciones de rigurosidad, cuando se utilizó el ADN genómico de distintas especies pertenecientes al subgénero Leishmania. El ensayo L280-PCR resultó negativo para el ADN genómico de distintas especies del subgénero Viannia al igual que para el ADN de otros organismos kinetoplastidos o humano. Los resultados sugieren que el ensayo L280-PCR es específico del subgénero Leishmania. Abstract in english Leishmania is the causal agent of the leishmaniasis disease. The different species of this protozoa parasite are grouped in two subgenera, Viannia and Leishmania, according to their development in the sandfly vector. A specific PCR assay, ?500-PCR, has been developed for the Viannia subgenus using t [...] he genomic ?500 DNA sequence. In the present work we present the isolation and identification of a genomic sequence of 280 bp, L280, obtained from genomic DNA of Leishmania (Leishmania) mexicana after application of the ?500-PCR assay at low stringency. After partial sequencing of L280 a PCR assay was generated, L280-PCR, this yielded a product of 260 bp at different conditions of stringency, when genomic DNA of different species of Leishmania subgenus was used. The L280-PCR assay was negative to genomic DNA of species belonging to the Viannia subgenus and also to other kinetoplastid organisms and human. The results suggest specificity of the L280-PCR assay for the Leishmania subgenus.

  11. Evidence for a neotropical origin of Leishmania

    Scientific Electronic Library Online (English)

    HA, Noyes; DA, Morrison; ML, Chance; JT, Ellis.

    2000-08-01

    Full Text Available Contradictory biogeographic hypotheses for either a Neotropical or a Palaearctic origin of the genus Leishmania have been proposed. Hypotheses constructed on the basis of biogeographic data must be tested against an independent dataset and cannot be supported by biogeographic data alone. In the abse [...] nce of a fossil record for the Leishmania these two hypotheses were tested against a combined dataset of sequences from the DNA polymerase A catalytic subunit and the RNA polymerase II largest subunit. The phylogeny obtained provided considerable support for a Neotropical origin of the genus Leishmania and leads us to reject the hypothesis for a Palaearctic origin.

  12. Detecção de DNA de Leishmania braziliensis em pacientes de leishmaniose tegumentar americana Detección de DNA de Leishmania braziliensis en pacientes de leishmaniose tegumentaria americana Detection of Leishmania braziliensis DNA in American tegumentary leishmaniasis patients

    OpenAIRE

    Leila Martins; Aline Alexandrino; Georgia Guimarães

    2010-01-01

    Foi realizado diagnóstico para leishmaniose tegumentar americana a partir de sangue de pacientes residentes em dois municípios endêmicos do estado de Pernambuco. O DNA de 119 amostras de sangue foi extraído e submetido a reação em cadeia da polimerase. Utilizaram-se primers do minicírculo do DNA do cinetoplasto (kDNA) de Leishmania braziliensis, circulante em Pernambuco, cuja seqüência-alvo gera um fragmento de 750 pares de bases. No total 58 (48,7%) indivíduos apresentaram amplificação posit...

  13. Design of inhibitors for nucleoside hydrolase from Leishmania donovani using molecular dynamics studies

    Scientific Electronic Library Online (English)

    Tanos C. C., França; Maria do Ramo M., Rocha; Bruno M., Reboredo; Magdalena N., Rennó; Luzineide W., Tinoco; José D., Figueroa-Villar.

    Full Text Available Neste trabalho é proposto o primeiro modelo por homologia para a nucleosídeo hidrolase de Leishmania donovani construído a partir das estruturas das nucleosídeo hidrolases de Crithidia fasciculata e de Leishmania major. Usando as informações de interação entre o inibidor p-aminofeniliminoribitol e a [...] nucleosídeo hidrolase de Crithidia fasciculata foram planejados dois novos potenciais inibidores, os quais apresentam novas interações com alguns resíduos da bolsa hidrofóbica do sítio ativo do modelo. Simulações por dinâmica molecular dos protótipos ancorados nos sítios ativos do modelo e das enzimas usadas como moldes, mostraram que, diferente do p-aminofeniliminoribitol, eles permaneceram ancorados nos sítios ativos das três enzimas ao longo de toda a dinâmica, interagindo fortemente com os aminoácidos da bolsa hidrofóbica. Abstract in english In this work we propose the first homology model for nucleoside hydrolase from Leishmania donovani, built based on the crystallographic structures of Crithidia fasciculata and Leishmania major nucleoside hydrolases. We used the interaction information from the crystallographic model of the enzyme of [...] C. fasciculata in complex with the inhibitor p-aminophenyliminoribitol, to design two new potential inhibitors, which present new interactions with some residues of the hydrophobic pocket of the model active site. Molecular dynamics simulations of the prototypes inside the active sites of the model and the template enzymes showed that, differently from p-aminophenyliminoribitol, they remained tightly bound inside the active sites, interacting strongly with the amino acids from the hydrophobic pocket.

  14. Leishmania (infantum) chagasi in canine urinary sediment / Leishmania (infantum) chagasi em sedimento urinário canino

    Scientific Electronic Library Online (English)

    Ivete Lopes de, Mendonça; Joilson Ferreira, Batista; Leucio Camara, Alves.

    2015-03-01

    Full Text Available A leishmaniose visceral canina (LVC) é uma doença de difícil diagnóstico. Principalmente devido à presença de animais assintomáticos, a diversidade da sintomatologia clínica apresentada e também pela dificuldade em se obter uma prova diagnóstica que reúna alta sensibilidade e especificidade. O objet [...] ivo deste trabalho foi relatar a presença de L. (infantum) chagasi em meio de cultura, utilizando-se sedimento urinário. Foram utilizados neste experimento, 70 cães provenientes do Hospital Veterinário Universitário da Universidade Federal do Piauí e do Centro de Controle de Zoonoses de Teresina, com raça, sexo e idade variada. Foram realizados exames sorológicos: TR DPP® Leishmaniose Visceral Canina (DPP) e Ensaio Imunoenzimático Leishmaniose Visceral Canina (ELISA), exames parasitológicos de amostras de medula e/ou linfonodo e cultura de sedimento urinário. Em 61,0% (43/70) dos animais estudados, observou-se presença de Leishmania em medula e/ou linfonodo, e destes 9,30% (4/43) foram positivos na cultura de sedimento urinário. Nos exames sorológicos, 70,0% (49/70) dos animais apresentavam-se reativos no DPP e 78,2% (55/70) no ELISA. Pode-se concluir, neste estudo, que é possível diagnosticar a LVC por meio da cultura de sedimento urinário. Abstract in english Canine visceral leishmaniasis (CVL) is difficult to diagnosis, mainly due to the presence of asymptomatic animals, the diversity of clinical symptoms and the difficulty in obtaining diagnostic evidence of high sensitivity and specificity. The purpose of this study was to diagnose CVL in urinary sedi [...] ment of 70 dogs of different breeds, sexes and ages from the veterinary hospital of the Federal University of Piauí and Zoonosis Control Center of Teresina, Brazil. The serological tests were TR DPP® for CVL and enzyme-linked immunosorbent assay (ELISA) for CVL, parasitological exams of bone marrow and lymph nodes and urine sediment cultures. Leishmania was detected in the bone marrow and/or lymph node of 61.0% of the animals (43/70), and urine sediment culture was positive in 9.30% (4/43) of these animals. In the serological exams, 70.0% (49/70) were reactive using the DPP and 78.2% (55/70) were reactive using ELISA. The goal of this study was to diagnose the presence of L. (infantum) chagasi in a culture of urinary sediment.

  15. Persistent Infections by Leishmania (Viannia) braziliensis

    OpenAIRE

    José Luis Ramírez; Palmira Guevara

    1997-01-01

    Here we review the phenomenon of persistency in Leishmania (Viannia) braziliensis infections. In other Leishmania species where appropriate animal models exist, considerable advances in the understanding of basic immunologic mechanisms of persistency have been made; for a review see Aebisher (1994). On the contrary, the evidences of persistence in infections with L. braziliensis rest on studies of human clinical cases many of which we summarized and discussed in this work

  16. Persistent Infections by Leishmania (Viannia) braziliensis

    Scientific Electronic Library Online (English)

    José Luis, Ramírez; Palmira, Guevara.

    1997-05-01

    Full Text Available Here we review the phenomenon of persistency in Leishmania (Viannia) braziliensis infections. In other Leishmania species where appropriate animal models exist, considerable advances in the understanding of basic immunologic mechanisms of persistency have been made; for a review see Aebisher (1994). [...] On the contrary, the evidences of persistence in infections with L. braziliensis rest on studies of human clinical cases many of which we summarized and discussed in this work

  17. Evaluation of enzyme-linked immunosorbent assay using crude Leishmania and recombinant antigens as a diagnostic marker for canine visceral leishmaniasis

    Directory of Open Access Journals (Sweden)

    Eliza Yoshie do Rosário

    2005-04-01

    Full Text Available The performances of ELISA assays with different antigen preparations, such as Leishmania amazonensis or L. chagasi lysates and the recombinant antigens rK-39 and rK-26, were compared using sera or eluates from dried blood collected on filter paper to detect anti-Leishmania antibodies in dogs from a visceral leishmaniasis-endemic area in Brazil. Of 115 IFAT-reactive dogs at 1:40 titre, 106 (92.2% were positive in parasitological exams (skin and/or spleen. These animals were compared to healthy animals (n = 25, negative for IFAT at a titre of 1:40 and parasitological exams. The sensitivities of crude and recombinant antigens were similar and remarkably high for both sera and eluates (97-100%. Specificity was higher than 96% for sera and eluates for different antigens, except for L. chagasi antigen using eluates (88%. Concordance values among the tests were higher either for sera or eluates (J = 0.95-1.00. High concordances were observed between sera and eluates tested with different antigens (kappa = 0.93-0.97. Crude and recombinant antigens identified different clinical phases of canine leishmaniasis. These results show that eluates could be used in canine surveys to identify L. chagasi infection. Recombinant antigens added little when compared to crude antigen in identifying positive dogs. Cross-reactivity with other diseases whose distribution often overlaps VL-endemic areas is a limitation of crude antigen use however.

  18. Evaluation of enzyme-linked immunosorbent assay using crude Leishmania and recombinant antigens as a diagnostic marker for canine visceral leishmaniasis

    Scientific Electronic Library Online (English)

    Eliza Yoshie do, Rosário; Odair, Genaro; João C, França-Silva; Roberto T da, Costa; Wilson, Mayrink; Alexandre Barbosa, Reis; Mariângela, Carneiro.

    2005-04-01

    Full Text Available The performances of ELISA assays with different antigen preparations, such as Leishmania amazonensis or L. chagasi lysates and the recombinant antigens rK-39 and rK-26, were compared using sera or eluates from dried blood collected on filter paper to detect anti-Leishmania antibodies in dogs from a [...] visceral leishmaniasis-endemic area in Brazil. Of 115 IFAT-reactive dogs at 1:40 titre, 106 (92.2%) were positive in parasitological exams (skin and/or spleen). These animals were compared to healthy animals (n = 25), negative for IFAT at a titre of 1:40 and parasitological exams. The sensitivities of crude and recombinant antigens were similar and remarkably high for both sera and eluates (97-100%). Specificity was higher than 96% for sera and eluates for different antigens, except for L. chagasi antigen using eluates (88%). Concordance values among the tests were higher either for sera or eluates (J = 0.95-1.00). High concordances were observed between sera and eluates tested with different antigens (kappa = 0.93-0.97). Crude and recombinant antigens identified different clinical phases of canine leishmaniasis. These results show that eluates could be used in canine surveys to identify L. chagasi infection. Recombinant antigens added little when compared to crude antigen in identifying positive dogs. Cross-reactivity with other diseases whose distribution often overlaps VL-endemic areas is a limitation of crude antigen use however.

  19. Detección de Leishmania spp. en base al gen que codifica la proteína HSP20 / Detection of Leishmania spp. based on the gene encoding HSP20

    Scientific Electronic Library Online (English)

    Ana M., Montalvo; Jorge, Fraga; Omaira, Rodríguez; Orestes, Blanco; Alejandro, Llanos-Cuentas; Ana L., García; Braulio M., Valencia; Carlos, Muskus; Gert, Van der Auwera; José M., Requena.

    2014-12-01

    Full Text Available Objetivos. Explorar una nueva diana para el diagnóstico molecular de Leishmania. Materiales y métodos. Se evaluó la utilidad del gen que codifica la proteína de choque térmico de 20kDa (hsp20) para la detección de Leishmania por medio de la reacción en cadena de la polimerasa (PCR).Se normalizó la P [...] CR y se determinaron los parámetros analíticos, así como la validez y seguridad diagnóstica y la concordancia con la PCR-18S. Se evaluó la PCR-hsp20 con ADN obtenido de un grupo de muestras clínicas de distinta procedencia. Resultados. Los parámetros analíticos resultaron adecuados. La sensibilidad obtenida fue de 86% y la especificidad del 100%, la concordancia con el método de referencia resultó buena (? = 0,731), lo que apoya su posible uso para el diagnóstico. La posibilidad de identificación posterior de la especie mediante secuenciación del producto amplificado le confiere una ventaja adicional. Conclusiones. Se demuestra la utilidad de este gen como una nueva diana para la detección del género Leishmania. Debido a su potencial, se recomienda mejorar la sensibilidad del procedimiento y realizar su evaluación en diversas regiones endémicas. Abstract in english Objectives. Explore a new target for molecular diagnosis of Leishmania. Materials and methods. We evaluated the utility of the gene that encodes the heat shock protein 20-kDa (Hsp20) for detecting Leishmania by polymerase chain reaction (PCR). PCR was normalized and analytical parameters were determ [...] ined, as well as the validity and diagnostic accuracy, and concordance with the PCR - 18S. PCR-Hsp20 with DNA was obtained from a group of clinical samples from different sources. Results. The analytical parameters were adequate. The sensitivity obtained was 86% and the specificity was 100%. The concordance with the reference method was good (? = 0.731), which supports its potential use for diagnosis. The possibility of subsequent identification of the species by sequencing the amplified product gives an additional advantage. Conclusions. The usefulness of this gene as a new target for the detection of Leishmania was demonstrated. Because of its potential, it is recommended to improve the sensitivity of the method and to evaluate it in different endemic regions.

  20. Detección de Leishmania spp. en base al gen que codifica la proteína HSP20 / Detection of Leishmania spp. based on the gene encoding HSP20

    Scientific Electronic Library Online (English)

    Ana M, Montalvo; Jorge, Fraga; Omaira, Rodríguez; Orestes, Blanco; Alejandro, Llanos-Cuentas; Ana L, García; Braulio M, Valencia; Carlos, Muskus; Gert, Van der Auwera; José M, Requena.

    2014-10-01

    Full Text Available Objetivos. Explorar una nueva diana para el diagnóstico molecular de Leishmania. Materiales y métodos. Se evaluó la utilidad del gen que codifica la proteína de choque térmico de 20kDa (hsp20) para la detección de Leishmania por medio de la reacción en cadena de la polimerasa (PCR).Se normalizó la P [...] CR y se determinaron los parámetros analíticos, así como la validez y seguridad diagnóstica y la concordancia con la PCR-18S. Se evaluó la PCR-hsp20 con ADN obtenido de un grupo de muestras clínicas de distinta procedencia. Resultados. Los parámetros analíticos resultaron adecuados. La sensibilidad obtenida fue de 86% y la especificidad del 100%, la concordancia con el método de referencia resultó buena (? = 0,731), lo que apoya su posible uso para el diagnóstico. La posibilidad de identificación posterior de la especie mediante secuenciación del producto amplificado le confiere una ventaja adicional. Conclusiones. Se demuestra la utilidad de este gen como una nueva diana para la detección del género Leishmania. Debido a su potencial, se recomienda mejorar la sensibilidad del procedimiento y realizar su evaluación en diversas regiones endémicas. Abstract in english Objectives. Explore a new target for molecular diagnosis of Leishmania. Materials and methods. We evaluated the utility of the gene that encodes the heat shock protein 20-kDa (Hsp20) for detecting Leishmania by polymerase chain reaction (PCR). PCR was normalized and analytical parameters were determ [...] ined, as well as the validity and diagnostic accuracy, and concordance with the PCR - 18S. PCR-Hsp20 with DNA was obtained from a group of clinical samples from different sources. Results. The analytical parameters were adequate. The sensitivity obtained was 86% and the specificity was 100%. The concordance with the reference method was good (? = 0.731), which supports its potential use for diagnosis. The possibility of subsequent identification of the species by sequencing the amplified product gives an additional advantage. Conclusions. The usefulness of this gene as a new target for the detection of Leishmania was demonstrated. Because of its potential, it is recommended to improve the sensitivity of the method and to evaluate it in different endemic regions.

  1. American cutaneous leishmaniasis caused by Leishmania (Viannia) braziliensis resistant to meglumine antimoniate, but with good response to pentamidine: a case report / Leishmaniose cutânea americana causada pela Leishmania (Viannia) braziliensis resistente ao antimoniato de meglumina e com boa resposta terapêutica à pentamidina: relato de um caso

    Scientific Electronic Library Online (English)

    Maria Inês Fernandes, Pimentel; Cibele, Baptista; Évelyn Figueiredo, Rubin; Érica de Camargo Ferreira e, Vasconcellos; Marcelo Rosandiski, Lyra; Mariza de Matos, Salgueiro; Maurício Naoto, Saheki; Cláudia Maria Valete, Rosalino; Maria de Fátima, Madeira; Aline Fagundes da, Silva; Eliame Mouta, Confort; Armando de Oliveira, Schubach.

    2011-04-01

    Full Text Available Relatamos um caso de um militar brasileiro com leishmaniose cutânea, cuja lesão reativou após dois tratamentos sistêmicos com antimoniato de meglumina. Foi tratado com anfotericina B, mas precisou interromper por intolerância à medicação. Após isolamento de Leishmania sp, seis infiltrações intralesi [...] onais de antimoniato de meglumina foram realizadas, sem resposta. Promastigotas de Leishmania sp. foram novamente isoladas. Foi submetido a tratamento intramuscular com pentamidina (4mg/kg). Parasitas da primeira e segunda biópsias foram identificados como Leishmania (Viannia) braziliensis; os da primeira biópsia eram mais sensíveis ao antimoniato de meglumina in vitro do que os da segunda biópsia. A lesão não reativou. Abstract in english This is a case report of a Brazilian soldier with cutaneous leishmaniasis. The lesion relapsed following two systemic treatments with meglumine antimoniate. The patient was treated with amphotericin B, which was interrupted due to poor tolerance. Following isolation of Leishmania sp., six intralesio [...] nal infiltrations of meglumine antimoniate resulted in no response. Leishmania sp promastigotes were again isolated. The patient was submitted to intramuscular 4mg/kg pentamidine. Parasites from the first and second biopsies were identified as Leishmania (Viannia) braziliensis; those isolated from the first biopsy were more sensitive to meglumine antimoniate in vitro than those isolated from the second biopsy. No relapse was observed.

  2. American cutaneous leishmaniasis caused by Leishmania (Viannia braziliensis resistant to meglumine antimoniate, but with good response to pentamidine: a case report Leishmaniose cutânea americana causada pela Leishmania (Viannia braziliensis resistente ao antimoniato de meglumina e com boa resposta terapêutica à pentamidina: relato de um caso

    Directory of Open Access Journals (Sweden)

    Maria Inês Fernandes Pimentel

    2011-04-01

    Full Text Available This is a case report of a Brazilian soldier with cutaneous leishmaniasis. The lesion relapsed following two systemic treatments with meglumine antimoniate. The patient was treated with amphotericin B, which was interrupted due to poor tolerance. Following isolation of Leishmania sp., six intralesional infiltrations of meglumine antimoniate resulted in no response. Leishmania sp promastigotes were again isolated. The patient was submitted to intramuscular 4mg/kg pentamidine. Parasites from the first and second biopsies were identified as Leishmania (Viannia braziliensis; those isolated from the first biopsy were more sensitive to meglumine antimoniate in vitro than those isolated from the second biopsy. No relapse was observed.Relatamos um caso de um militar brasileiro com leishmaniose cutânea, cuja lesão reativou após dois tratamentos sistêmicos com antimoniato de meglumina. Foi tratado com anfotericina B, mas precisou interromper por intolerância à medicação. Após isolamento de Leishmania sp, seis infiltrações intralesionais de antimoniato de meglumina foram realizadas, sem resposta. Promastigotas de Leishmania sp. foram novamente isoladas. Foi submetido a tratamento intramuscular com pentamidina (4mg/kg. Parasitas da primeira e segunda biópsias foram identificados como Leishmania (Viannia braziliensis; os da primeira biópsia eram mais sensíveis ao antimoniato de meglumina in vitro do que os da segunda biópsia. A lesão não reativou.

  3. Detection of Leishmania infantum in the smegma of infected dogs / Detecção de Leishmania infantum no esmegma de cães infectados

    Scientific Electronic Library Online (English)

    L.C., Silva; V.P., Assis; V.M., Ribeiro; W.L., Tafuri; J.C., Toledo Júnior; S.O., Silva; M.N., Melo; M.A., Rachid; G.R., Valle.

    2014-06-01

    Full Text Available Tendo em vista a transmissão venérea da leishmaniose visceral do cão para a cadela, o objetivo deste estudo foi verificar se a superfície peniana e o esmegma de cães infectados poderiam ser a fonte de parasitas para a fêmea. Amostras de sêmen e esmegma de 12 cães infectados com Leishmania infantum f [...] oram submetidas à identificação do DNA do parasita por PCR. As incidências de positividade no sêmen (41,7%) e no esmegma (50,0%) foram semelhantes (P>0,05; teste exato de Fisher), sendo 58,3% dos cães positivos para sêmen e/ou esmegma. A positividade para sêmen e esmegma juntos ocorreu em 33,3%, mas em 8,3% dos casos apenas no sêmen, e em 16,7% apenas no esmegma, o que revela uma concordância moderada entre os testes (K=0,5; índice Kappa). Conclui-se que a Leishmania infantum está presente no esmegma de cães contaminados, podendo ser a fonte de parasitas para o sêmen e a cadela. Abstract in english Considering the venereal transmission of visceral leishmaniasis from dogs to bitches, the aim of this study was to verify if the penile surface and smegma from infected dogs can be the source of parasites in bitches. Twelve Leishmania infantum infected dogs had semen and smegma samples collected for [...] submission to PCR identification of the DNA of the parasite. Semen (41.7%) and smegma (50.0%) have similar positive incidence (P>0.05; Fisher's exact test), with 58.3% of the dogs positive for semen and/or smegma samples. The proportion of positivity for both semen and smegma was 33.3%, but 8.3% was positive only for semen, and 16.7% only for smegma, revealing a moderate agreement between tests (K=0.5; Kappa index). It was concluded that Leishmania infantum is present in the smegma of contaminated dogs and it can be a source of parasites for the semen and the bitch.

  4. Nematodes of Amazonian birds, with a description of Hoazinstrongylus amazonensis n.gen.n.sp. (Trichostrongylidae, Libyostrongylinae)

    OpenAIRE

    Magalha?es Pinto, R.; Delir Corrêa Gomes

    1985-01-01

    During recent studies of the parasites of birds from the Amazonian Regio, the following nematodes were recovered: Hoazinstrongylus amazonensis n.gen.n.sp. from Opisthocomus hoazin (Muller, 1776); Ascaridia columbae (Gmel., 1790) Travassos, 1913, from Leptotila r. rufaxilla (Richard & Bernard, 1712) representing a new host record; Inglisakis ibanezi Freitas, Vicente & Santos, 1969, Cyrnea (C.) semilunaris (Molin, 1860) Seurat, 1914 and Thelazia digitata Travassos, 1918. A compelte description ...

  5. Histoplasmose em região de palato duro simulando lesão causada por Leishmania

    Directory of Open Access Journals (Sweden)

    São Thiago Paulo de Tarso

    1998-01-01

    Full Text Available Os autores relatam um caso de histoplasmose em indivíduo com suspeita clínica de leishmaniose mucosa. A infecção por Leishmania foi descartada, pela negatividade do teste de Montenegro e ausência do parasita. O diagnóstico de histoplasmose foi confirmado pelo encontro do fungo na lesão e o seu isolamento em Ágar-Sabouraud. O tratamento do paciente com anfotericina B resultou na remissão da lesão.

  6. Leishmania (Viannia lainsoni (Kinetoplastida: Trypanosomatidae, a divergent Leishmania of the Viannia subgenus: a mini review

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    José R Corrêa

    2005-10-01

    Full Text Available Leishmania (Viannia lainsoni is the Leishmania species that presents the most distinct biological (morphology, growth in axenic culture medium, biochemical (enzymatic electrophoresis profile, and molecular biology characteristics, when compared to other species of the Viannia subgenus. Development of promastigote forms of this parasite attached to the wall of the pyloric and hind gut regions of sand fly vectors is a solid characteristic that allows its positioning in the Viannia subgenus. However, taxonomic data from biochemical and molecular techniques on this Leishmania species are still not conclusive. It is evident the difficulty in taxonomically positioning this borderline Leishmania species. In this review we present the data accumulated since L. (Viannia lainsoni has been described and we discuss its position in the Viannia subgenus.

  7. Susceptibility of spiny rats (Proechimys semispinosus to Leishmania (Viannia panamensis and Leishmania (Leishmania chagasi

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    BL Travi

    2002-09-01

    Full Text Available The role of Proechimys semispinosus as reservoir of Leishmania (Viannia panamensis on the Colombian Pacific coast was experimentally evaluated. The susceptibility to L. chagasi also was assessed to determine the utility of this rodent as a model for studying reservoir characteristics in the laboratory. Wild-caught animals were screened for natural trypanosomatid infections, and negative individuals were inoculated intradermally (ID in the snout or feet with 10(7 promastigotes of L. panamensis. L. chagasi was inoculated intracardially (10(7 promastigotes or ID in the ear (10(8 promastigotes. PCR-hybridization showed that 15% of 33 spiny rats were naturally infected with L. Viannia sp. Animals experimentally infected with L. panamensis developed non-ulcerated lesions that disappeared by the 7th week post-infection (p.i. and became more resistant upon reinfection. Infectivity to sand flies was low (1/20-1/48 infected/fed flies and transient, and both culture and PCR-hybridization showed that L. panamensis was cleared by the 13th week p.i. Animals inoculated with L. chagasi became subclinically infected and were non-infective to sand flies. Transient infectivity to vectors of spiny rats infected with L. panamensis, combined with population characteristics, e.g., abundance, exploitation of degraded habitats and high reproductive rates, could make them epidemiologically suitable reservoirs.

  8. Detection of Leishmania infantum in Lutzomyia longipalpis captured in Campo Grande, MS / Detecção de Leishmania infantum em Lutzomyia longipalpis capturados em Campo Grande, MS

    Scientific Electronic Library Online (English)

    Rodrigo Casquero, Cunha; Renato, Andreotti; Marlon Cezar, Cominetti; Elaine Araújo, Silva.

    2014-04-01

    Full Text Available A Leishmaniose é uma zoonose causada por protozoários do gênero Leishmania (Ross 1903), objetos de considerável atenção em medicina humana e veterinária. Na cidade de Campo Grande – MS, o agente etiológico da Leishmaniose Visceral é Leishmania infantum (= L. chagasi), e o principal vetor é a espécie [...] Lutzomyia longipalpis, que representa cerca de 92,9% da população de flebotomíneos. Este trabalho teve como objetivo avaliar a PCR em tempo real como ferramenta para a detecção de kDNA de L. infantum em flebotomíneos, comparando-se com PCR convencional. Flebotomíneos dessa espécie foram capturados, somando 38 amostras de 1 a 4 espécimens cada, distribuídas em 13 bairros, divididos entre as 7 regiões urbanas da cidade de Campo Grande – MS, e armazenados a ?70 °C até a extração de ADN e amplificação por PCR e PCR em tempo real. Das 38 amostras testadas, foram encontradas 3 amostras positivas pela PCR convencional e 11 pela PCR em Tempo Real. Na otimização da PCR em tempo real, a temperatura de dissociação do amplificado foi de 82, 89 °C. Neste estudo, utilizando-se a técnica da PCR em tempo real, foi possível detectar a presença desse agente em 6 dos 13 bairros amostrados, todos na periferia da cidade, indicando o maior potencial enzoótico dessas regiões, que têm maior proximidade com reservas de matas naturais. Conclui-se que a PCR em tempo real pode ser utilizada para estudo epidemiológico de L. infantum. Abstract in english Leishmaniasis is a zoonotic disease caused by protozoa of the genus Leishmania (Ross, 1903) and is the focus of considerable attention in human and veterinary medicine. In the city of Campo Grande, MS, the causative agent of visceral leishmaniasis is Leishmania infantum (= L. chagasi) primary vector [...] , comprising approximately 92.9% of the local sandfly population, is Lutzomyia longipalpis. The aim of this work was to compare real-time PCR with PCR as a tool for the detection of the kinetoplast DNA (kDNA) of L. infantum in sandflies. Sandflies of this species were caught, and a total of 38 samples with 1-4 individuals in each sample were obtained; these were distributed across 13 districts and divided between seven urban areas of the city of Campo Grande, MS. Three positive samples were found by PCR and, when using real-time PCR, this was able to detect the presence of this agent in 6 of the 13 districts sampled, which were all located on the outskirts of the city, where indicates the greater enzootic potential of these regions, as they are closer to natural forest reserves. We conclude that real-time PCR can be used for epidemiological studies of L. infantum.

  9. Host factors influencing outcome of Leishmania mexicana infection in mice

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    Pamela Lane Moriearty

    1983-03-01

    Full Text Available Studies were undertaken to determine the influence of several host-related parameters on the course of Leishmania mexicana mexicana infection in inbred C57B1/10 (C57 and outbred albino (OA mice. An important influence of the following variables was demonstrated: Host strain: lesions in C57s were significantly less variable in size and outcome than those of OAs under the conditions studied and even when persistent developed at a slower rate. Host age: Subcutanous injection of 2 x 10 [raised to the power of 4] to 2 x 10 [raised to the power of 6] amastigotes into the dorsum of the rear paw produced significantly larger lesions which healed more slowly in 2 mo. old C57s than in 4 mo. old mice. Reduced healing ability was observed in older (8 mo. old female C57s, and low mortality occurred after 15 months of age in infected mice of both sexes. Lesion site: Following amastigote infection, lesions in paws of most C57s regress within 15 - 25 wks. In contrast, perinasal legions produced with the same number of parasites tend to persist for the life of the animal as slowly spreading irregular nodules. In animals infected in both locations, each lesion site behaves similarly to that in singly infected animals of the same age, i.e. regression in the two sites is independent. Our results indicate that while host strain may strongly influence infection outcoem, such variables as lesion site and host age play important roles and may explain, in part, reported inter- and intraexperimental variability in responses of murine hosts to a given leishmanial parasite.Estudando a influência de alguns parâmetros relacionados ocm o hospedeiro no curso da infecção com Leishmania mexicana mexicana em camundongos singênicos C57B1/10 (C57 e não singênicos albinos (OA demonstramos o papel importante das variáveis enumeradas a seguir: Cepa do hospedeiro: o desenvolvimento e tamanho das lesões variaram significativamente menos nos camundongos C57 do que nos OA. Idade do hospedeiro: inóculos subcutâneos de 2 x 10 [elevado a 4] a 2 x 10 [elevado a 6] amastigotas no dorso da pata trasiera produziram lesões significativamente maiores e que regrediram mais lentamente nos camundongos C57 de 2 meses de idade do que nos de 4 meses. Enquanto uma redução da capacidade de curar lesões foi também observada nas fêmeas C57 mais idosas (8 meses, uma mortalidade baixa ocorreu nos animais infectados de 15 meses de idade, de ambos os sexos. Local da lesão: as lesões de pata de C57 infectados com amastigotas regrediram entre 15 a 25 semanas, mas os da região perinasal, produzidas nesses animais com idêntico inóculo parasitário, foram persistente e progressivos, formando nódulos irregulares. Nos animais infectados simultaneamente em ambas as regiões, cada uma das lesões apresentou uma evolução semelhante àquela observada nos animais da mesma idade infectados em uma das regiões isoladamente, demonstrando que as involuções do processo nesses locais são fenômenos independentes. Assim, esses resultados indicam que enquanto a cepa do hospedeiro pode influir grandemente no curso da infecção, tais variávei como o sítio da lesão e a idade do animal também desempenham papéis importantes, podendo explicar, pelo menos em parte, a variabilidade nas respostas do hospediero face à infecção com uma determinada Leishmania.

  10. Host factors influencing outcome of Leishmania mexicana infection in mice

    Scientific Electronic Library Online (English)

    Pamela Lane, Moriearty; Gabriel, Grimaldi Junior.

    1983-03-01

    Full Text Available Estudando a influência de alguns parâmetros relacionados ocm o hospedeiro no curso da infecção com Leishmania mexicana mexicana em camundongos singênicos C57B1/10 (C57) e não singênicos albinos (OA) demonstramos o papel importante das variáveis enumeradas a seguir: Cepa do hospedeiro: o desenvolvime [...] nto e tamanho das lesões variaram significativamente menos nos camundongos C57 do que nos OA. Idade do hospedeiro: inóculos subcutâneos de 2 x 10 [elevado a 4] a 2 x 10 [elevado a 6] amastigotas no dorso da pata trasiera produziram lesões significativamente maiores e que regrediram mais lentamente nos camundongos C57 de 2 meses de idade do que nos de 4 meses. Enquanto uma redução da capacidade de curar lesões foi também observada nas fêmeas C57 mais idosas (8 meses), uma mortalidade baixa ocorreu nos animais infectados de 15 meses de idade, de ambos os sexos. Local da lesão: as lesões de pata de C57 infectados com amastigotas regrediram entre 15 a 25 semanas, mas os da região perinasal, produzidas nesses animais com idêntico inóculo parasitário, foram persistente e progressivos, formando nódulos irregulares. Nos animais infectados simultaneamente em ambas as regiões, cada uma das lesões apresentou uma evolução semelhante àquela observada nos animais da mesma idade infectados em uma das regiões isoladamente, demonstrando que as involuções do processo nesses locais são fenômenos independentes. Assim, esses resultados indicam que enquanto a cepa do hospedeiro pode influir grandemente no curso da infecção, tais variávei como o sítio da lesão e a idade do animal também desempenham papéis importantes, podendo explicar, pelo menos em parte, a variabilidade nas respostas do hospediero face à infecção com uma determinada Leishmania. Abstract in english Studies were undertaken to determine the influence of several host-related parameters on the course of Leishmania mexicana mexicana infection in inbred C57B1/10 (C57) and outbred albino (OA) mice. An important influence of the following variables was demonstrated: Host strain: lesions in C57s were s [...] ignificantly less variable in size and outcome than those of OAs under the conditions studied and even when persistent developed at a slower rate. Host age: Subcutanous injection of 2 x 10 [raised to the power of 4] to 2 x 10 [raised to the power of 6] amastigotes into the dorsum of the rear paw produced significantly larger lesions which healed more slowly in 2 mo. old C57s than in 4 mo. old mice. Reduced healing ability was observed in older (8 mo. old) female C57s, and low mortality occurred after 15 months of age in infected mice of both sexes. Lesion site: Following amastigote infection, lesions in paws of most C57s regress within 15 - 25 wks. In contrast, perinasal legions produced with the same number of parasites tend to persist for the life of the animal as slowly spreading irregular nodules. In animals infected in both locations, each lesion site behaves similarly to that in singly infected animals of the same age, i.e. regression in the two sites is independent. Our results indicate that while host strain may strongly influence infection outcoem, such variables as lesion site and host age play important roles and may explain, in part, reported inter- and intraexperimental variability in responses of murine hosts to a given leishmanial parasite.

  11. Comparative genomic studies and in-silco strategies on Leishmania brazilensis, Leishmania infantum and Leishmania major: Conserved features, putative functions and potential drug target

    Directory of Open Access Journals (Sweden)

    Rakesh N. R.

    2013-06-01

    Full Text Available Leishmaniasis is a parasitic disease found largely in the tropics, which the World Health Organization has estimated infects 12 million people worldwide each year. More recently cases have been reported in Europe among intravenous drug users with HIV. At least 20 Leishmania species infect humans. New world parasite Leishmania. braziliensis is the causative agent of mucocutaneous Leishmaniasis. The old world species Leishmania. major and Leishmania. infantum, which are present in Africa, Europe and Asia, are parasites that cause cutaneous and visceral Leishmaniasis respectively. Aim of this Study is determination of major common genes and Protein identified Gene location on each of the chromosomes, and identification of a common protein drug target Promastigote surface antigen with available lead molecule acetylglucosamine (6-(acetylamino-6-deoxyhexopyranose and docking studies on those considered Leishmania species.

  12. Detecção de DNA de Leishmania braziliensis em pacientes de leishmaniose tegumentar americana Detección de DNA de Leishmania braziliensis en pacientes de leishmaniose tegumentaria americana Detection of Leishmania braziliensis DNA in American tegumentary leishmaniasis patients

    Directory of Open Access Journals (Sweden)

    Leila Martins

    2010-06-01

    Full Text Available Foi realizado diagnóstico para leishmaniose tegumentar americana a partir de sangue de pacientes residentes em dois municípios endêmicos do estado de Pernambuco. O DNA de 119 amostras de sangue foi extraído e submetido a reação em cadeia da polimerase. Utilizaram-se primers do minicírculo do DNA do cinetoplasto (kDNA de Leishmania braziliensis, circulante em Pernambuco, cuja seqüência-alvo gera um fragmento de 750 pares de bases. No total 58 (48,7% indivíduos apresentaram amplificação positiva e 61 (51,3% negativa. Das amostras positivas para a PCR, 37 (? 64% pertenciam a indivíduos tratados e sem lesão. Conclui-se que a técnica de PCR é eficaz para identificar o DNA de leishmânia em material de biópsias e em sangue venoso.Fue realizado diagnóstico para leishmaniosis tegumentaria americana a partir de sangre de pacientes residentes en dos municipios endémicos del estado de Pernambuco (Noreste de Brasil. El DNA de 119 muestras de sangre fue extraído y sometido a la reacción en cadena de la polimerasa. Se utilizaron primers del minicírculo del DNA del cinetoplasto (kDNA de Leishmania braziliensis, circulante en Pernambuco, cuya secuencia blanco genera un fragmento de 750 pares de bases. En total 58 (48,7% individuos presentaron amplificación positiva y 61 (51,3% negativa. De las muestras positivas para la PCR, 37 (?64% pertenecían a individuos tratados y sin lesión. Se concluyó que la técnica de la PCR es eficaz para identificar el DNA de Leishmania en material de biopsias y en sangre venosa.Diagnostic tests for American tegumentary leishmaniasis were performed on blood samples of patients living in two endemic municipalities in the state of Pernambuco, Northeastern Brazil. DNA was extracted from 119 samples and used as template for polymerase chain reaction (PCR analysis. The tests used primers specific for the kinetoplast mini-circle DNA (kDNA of Leishmania braziliensis, a species circulating in Pernambuco, which amplify a 750 base pair target sequence. In total, 58 subjects (48.7% showed positive PCR amplification and 61 (51.3% were negative. Of the PCR-positive samples, 37 (?64% were from treated, lesion-free subjects. In conclusion, the PCR technique is efficacious at identifying Leishmania DNA in biopsy and venous blood samples.

  13. Detecção de DNA de Leishmania braziliensis em pacientes de leishmaniose tegumentar americana / Detection of Leishmania braziliensis DNA in American tegumentary leishmaniasis patients / Detección de DNA de Leishmania braziliensis en pacientes de leishmaniose tegumentaria americana

    Scientific Electronic Library Online (English)

    Leila, Martins; Aline, Alexandrino; Georgia, Guimarães.

    2010-06-01

    Full Text Available Foi realizado diagnóstico para leishmaniose tegumentar americana a partir de sangue de pacientes residentes em dois municípios endêmicos do estado de Pernambuco. O DNA de 119 amostras de sangue foi extraído e submetido a reação em cadeia da polimerase. Utilizaram-se primers do minicírculo do DNA do [...] cinetoplasto (kDNA) de Leishmania braziliensis, circulante em Pernambuco, cuja seqüência-alvo gera um fragmento de 750 pares de bases. No total 58 (48,7%) indivíduos apresentaram amplificação positiva e 61 (51,3%) negativa. Das amostras positivas para a PCR, 37 (? 64%) pertenciam a indivíduos tratados e sem lesão. Conclui-se que a técnica de PCR é eficaz para identificar o DNA de leishmânia em material de biópsias e em sangue venoso. Abstract in spanish Fue realizado diagnóstico para leishmaniosis tegumentaria americana a partir de sangre de pacientes residentes en dos municipios endémicos del estado de Pernambuco (Noreste de Brasil). El DNA de 119 muestras de sangre fue extraído y sometido a la reacción en cadena de la polimerasa. Se utilizaron pr [...] imers del minicírculo del DNA del cinetoplasto (kDNA) de Leishmania braziliensis, circulante en Pernambuco, cuya secuencia blanco genera un fragmento de 750 pares de bases. En total 58 (48,7%) individuos presentaron amplificación positiva y 61 (51,3%) negativa. De las muestras positivas para la PCR, 37 (?64%) pertenecían a individuos tratados y sin lesión. Se concluyó que la técnica de la PCR es eficaz para identificar el DNA de Leishmania en material de biopsias y en sangre venosa. Abstract in english Diagnostic tests for American tegumentary leishmaniasis were performed on blood samples of patients living in two endemic municipalities in the state of Pernambuco, Northeastern Brazil. DNA was extracted from 119 samples and used as template for polymerase chain reaction (PCR) analysis. The tests us [...] ed primers specific for the kinetoplast mini-circle DNA (kDNA) of Leishmania braziliensis, a species circulating in Pernambuco, which amplify a 750 base pair target sequence. In total, 58 subjects (48.7%) showed positive PCR amplification and 61 (51.3%) were negative. Of the PCR-positive samples, 37 (?64%) were from treated, lesion-free subjects. In conclusion, the PCR technique is efficacious at identifying Leishmania DNA in biopsy and venous blood samples.

  14. Capacidad infectiva de promastigotes en fase estacionaria de leishmania (viannia) braziliensis y leishmania (viannia) peruviana, en línea celular dh82 / Infectivity of promastigotes in stationary phase of Leishmania (viannia) braziliensis and leishmania (viannia) peruviana, In cell line dh82

    Scientific Electronic Library Online (English)

    Karen Daphne, Calvay-Sánchez; Nyshon Máximo, Rojas-Palomino; Aidé Clorinda, Sandoval-Juarez; Alberto, Cisneros-Tarmeño; Cristian, Obregón-Cahuaya; Gloria Sonia, Minaya-Gómez.

    2015-03-01

    Full Text Available Objetivos. Determinar la capacidad infectiva de los promastigotes de Leishmania (V.) peruviana y Leishmania (V.) braziliensis en la línea celular macrófago-monocítica de Canis familiaris DH82. Materiales y métodos. Se realizó un estudio experimental durante los meses de enero a diciembre de 2013. Se [...] utilizaron cepas referenciales de Leishmania (V.) braziliensis MHOM/PE/84/LC53 y Leishmania (V.) peruviana MHOM/PE/84/LC26. La línea celular fue infectada con promastigotes en fase estacionaria y la capacidad infectiva fue determinada como el producto del porcentaje de macrófagos infectados por el promedio de amastigotes por macrófago infectado, observado al microscopio de epifluorescencia. Resultados. El 13% de formas metacíclicas para Leishmania (V.) braziliensis correspondió al día 17,5 posinoculación y para Leishmania (V.) peruviana un porcentaje de 9,5% en el día 14,5. No se encontró diferencia significativa entre la capacidad infectiva de los promastigotes en fase estacionaria de ambas especies. Conclusiones. Se recomienda evaluar la capacidad infectiva de los promastigotes metacíclicos de cepas de Leishmania (V.) peruviana y Leishmania (V.) braziliensis en líneas celulares, a fin de determinar el modelo de infección in vitro más adecuado, que permita efectuar estudios de susceptibilidad a las drogas leishmanicidas de mayor eficacia para el control de la enfermedad Abstract in english Objectives. To determine the infectivity of promastigotes of Leishmania (V.) peruviana and Leishmania (V.) braziliensis in monocyte-macrophage cell line DH82 of Canis familiaris. Materials and methods. Was conducted a experimental study during the months of january to december 2013. Were used strain [...] s of Leishmania were used (V.) braziliensis MHOM / PE / 84 / LC53 and Leishmania (V.) peruviana MHOM / PE / 84 / LC26. The cell line was infected with stationary phase promastigotes and infectivity was determined as the product of percent infected macrophages average amastigotes per macrophage observed in epifluorescence microscope.Results. 13% of metacyclic forms to Leishmania (V.) braziliensis corresponded to 17.5 days post inoculation and Leishmania (V.) peruviana a percentage of 9.5% on the day 14.5. No significant difference was found between infectivity of stationary phase promastigotes of both species. Conclusions. It is recommended assess the infectivity of metacyclic promastigotes peruviana strains of Leishmania (V.) and Leishmania (V.) braziliensis cell lines in order to determine the most appropriate model in vitro infection, allowing leishmanicidas make the drug more effective susceptibility studies for disease control.

  15. Comparative in-silico genome analysis of Leishmania (Leishmania) donovani: A step towards its species specificity.

    Science.gov (United States)

    S, Satheesh Kumar; R K, Gokulasuriyan; Ghosh, Monidipa

    2014-12-01

    Comparative genome analysis of recently sequenced Leishmania (L.) donovani was unexplored so far. The present study deals with the complete scanning of L. (L.) donovani genome revealing its interspecies variations. 60 distinctly present genes in L. (L.) donovani were identified when the whole genome was compared with Leishmania (L.) infantum. Similarly 72, 159, and 265 species specific genes were identified in L. (L.) donovani when compared to Leishmania (L.) major, Leishmania (L.) mexicana and Leishmania (Viannia) braziliensis respectively. The cross comparison of L. (L.) donovani in parallel with the other sequenced species of leishmanial led to the identification of 55 genes which are highly specific and expressed exclusively in L. (L.) donovani. We found mainly the discrepancies of surface proteins such as amastins, proteases, and peptidases. Also 415 repeat containing proteins in L. (L.) donovani and their differential distribution in other leishmanial species were identified which might have a potential role during pathogenesis. The genes identified can be evaluated as drug targets for anti-leishmanial treatment, exploring the scope for extensive future investigations. PMID:25606461

  16. Genetic analysis of leishmania parasites in Ecuador: are Leishmania (Viannia) panamensis and Leishmania (V.) Guyanensis distinct taxa?

    Science.gov (United States)

    Bañuls, A L; Jonquieres, R; Guerrini, F; Le Pont, F; Barrera, C; Espinel, I; Guderian, R; Echeverria, R; Tibayrenc, M

    1999-11-01

    In the course of an epidemiologic survey in Ecuador, the following collection of Leishmania stocks was isolated: 28 from patients with clinical signs of leishmaniasis, 2 from sloths, 1 from a dog, and 4 from sand flies. For genetic characterization of these stocks, multilocus enzyme electrophoresis (MLEE) and random amplified polymorphic DNA (RAPD) were used. Twenty six of the 35 stocks were identified as either Leishmania (V.) panamensis or L. (V.) guyanensis, 2 stocks were identified as L. (V.) braziliensis, the 2 stocks from sloths showed specific genotypes, and 5 stocks were characterized as hybrids between L. (V.) braziliensis and L. (V.) guyanensis. These data show that genetic diversity of Leishmania in Ecuador is high and that L. (V.) panamensis/guyanensis is the dominant group in this country. The genetic analysis questioned the distinctness between the two species L.(V.) panamensis and L. (V.) guyanensis, since MLEE and RAPD data did not indicate that L. (V.) panamensis and L. (V.) guyanensis correspond to distinct monophyletic lines. Population genetic analysis performed on the L. (V.) panamensis/guyanensis group favors the hypothesis of a basically clonal population structure. PMID:10586922

  17. Molecular karyotype characterization of Leishmania panamensis, Leishmania mexicana, and Leishmania major-like parasites: agents of cutaneous leishmaniasis in Ecuador.

    Science.gov (United States)

    Katakura, K; Matsumoto, Y; Gomez, E A; Furuya, M; Hashiguchi, Y

    1993-05-01

    Molecular karyotypes of Leishmania isolates from patients with cutaneous leishmaniasis in Ecuador were analyzed by pulsed-field gel electrophoresis (PFGE) and Southern blot hybridization. The DNA karyotypes of L. major-like parasites were similar between two human isolates from a lowland coastal and a highland Andean region, but were apparently different from those of eleven World Health Organization reference strains including L. major. The smallest chromosome of 240 kilobases in L. major-like parasites was found to belong to the 715-class of small linear chromosomal DNAs, which have been shown to appear in some lines of Leishmania. Chromosome banding patterns of L. mexicana isolates exhibited a novel, ordered, chromosomal ladder, and were identical among four human isolates and one canine isolate from a restricted geographic region in the Andes. On the other hand, minor chromosome size polymorphisms were observed among three L. panamensis isolates from different endemic regions near the Pacific Coast. Chromosomal locations of dihydrofolate reductase-thymidylate synthetase and P-glycoprotein genes revealed further differences in chromosomal organizations among these Leishmania species in Ecuador. These results indicate that karyotype analysis by PFGE is useful for epidemiologic studies of leishmaniasis in Ecuador. PMID:8517490

  18. Presence of Leishmania amastigotes in peritoneal fluid of a dog with leishmaniasis from Alagoas, Northeast Brazil Presença de formas amastigotas de Leishmania em fluido peritoneal de cão com leishmaniose proveniente de Alagoas, nordeste do Brasil

    Directory of Open Access Journals (Sweden)

    Filipe Dantas-Torres

    2006-08-01

    Full Text Available The goal of this short communication is to report the uncommon presence of intracellular amastigotes of Leishmania in peritoneal fluid of a dog with leishmaniasis from Alagoas State, Brazil. Physical examination of an adult male rottweiler suspected to be suffering of leishmaniasis revealed severe loss of weight, ascitis, splenomegaly, moderately enlarged lymph nodes, onychogryphosis, generalized alopecia, skin ulcers on the posterior limbs, and conjunctivitis. Samples of bone marrow, popliteal lymph node, skin ulcer, and peritoneal fluid were collected and smears of each sample were prepared and stained with hematoxylin and eosin. Numerous amastigotes were detected in bone marrow, popliteal lymph node, and skin ulcer smears. Smears of peritoneal fluid revealed the unusual presence of several free and intracellular amastigotes of Leishmania. Future studies are needed to determine whether the cytology of ascitic fluid represents a useful tool for diagnosis Leishmania infection in ascitic dogs, particularly in those living in areas where canine leishmaniasis is enzootic.O objetivo desta comunicação é descrever a presença incomum de formas amastigotas de Leishmania em fluido peritoneal de um cão com leishmaniose proveniente do Estado de Alagoas, nordeste do Brasil. O exame físico de um cão macho adulto da raça rottweiler, apresentando suspeita de leishmaniose, revelou perda de peso severa, esplenomegalia, linfonodos moderadamente aumentados, ascite, onicogrifose, alopecia generalizada, conjuntivite e presença de lesões cutâneas ulceradas localizadas nos membros posteriores. Foram coletadas amostras de medula óssea, linfonodo poplíteo, fluido peritoneal e úlcera cutânea. A partir das amostras, foram elaborados esfregaços, os quais foram corados pela hematoxilina e eosina. Inúmeras formas amastigotas foram detectadas na medula óssea, linfonodo poplíteo e úlcera cutânea. Esfregaços de fluido peritoneal revelaram a presença, não usual, de várias formas amastigotas livres e intracelulares. Futuros estudos serão necessários a fim de determinar se a citologia de líquido ascítico representa uma ferramenta útil para o diagnóstico da infecção por Leishmania em cães com ascite, particularmente naqueles que vivem em áreas onde a leishmaniose canina é enzoótica.

  19. Proteases de Leishmania: novos alvos para o desenvolvimento racional de fármacos / Leishmania proteases: new targets for rational drug development

    Scientific Electronic Library Online (English)

    Raquel Elisa da, Silva-López.

    1541-15-01

    Full Text Available [...] Abstract in english Leishmania causes tegumental and visceral diseases called leishmaniasis. Disease control is possible interrupting the transmission cycle, but HIV co-infection, chemotheraphy toxicity and lack of a vaccine are paramount difficulties. So, is necessary to study new Leishmania molecules and investigate [...] the possibility to develop rational drugs using these molecules as targets. Leishmania express many peptidases during their life, and cysteine are the most abundant protease and many inhibitors were developed but failed to kill parasites. On the other hand, inhibitors of serine proteases killed promastigotes, indicating the possibility of these enzymes to be important targets in the development of anti-Leishmania drugs.

  20. Description of Leishmania (Leishmania) forattinii sp. n., a new parasite infecting opossums and rodents in Brazil

    Scientific Electronic Library Online (English)

    Elizaide L. A., Yoshida; Cesar A Cuba, Cuba; Raquel da Silva, Pacheco; Elisa, Cupolillo; Celso Cruz, Tavares; Gerzia M. C., Machado; Hooman, Momen; Gabriel, Grimaldi Junior.

    1993-09-01

    Full Text Available A new parasite species of Leishmania is described, L. (Leishmania) forattinii sp. n., which was isolated from a pooled triturate of liver and spleen of a opossum (Didelphis marsupialis aurita) and from skin samples from a rodent (Proechmys iheringi denigratus), captured in primary forest on the Atla [...] ntic Cost of Brazil. Our results on the basis of biological and molecular criteria indicate that this taxonomically distinct parasite ias a new species of the L. mexicana complex, but closely related to L. (L.) aristidesi Laison & shaw, 1979, as revelated by phenetic and phylogenetic numerical analyses of the enzyme data. L. forattinii was clearly distinguishable from other Leishmania species of the genus usisng enzyme electrophoresis, monoclonal antibodies, molecular karyotypes, analysis of restriction enzyme digestion patterns of kinetoplast DNA (kDNA), as well as the use of kDNA hybridization procedures.

  1. LA BIOLOGÍA MOLECULAR DE LEISHMANIA SPP. COMO PUNTO DE PARTIDA PARA NUEVAS ALTERNATIVAS DE TRATAMIENTO / AMOLECULAR BIOLOGY LEISHMANIA SPP NEW DRUGS RESISTANCE / A BIOLOGIA MOLECULAR DE LEISHMANIA SPP. COMO PONTO DE PARTIDA PARA NOVAS ALTERNATIVAS DE TRATAMENTO

    Scientific Electronic Library Online (English)

    Martha Cecilia, Beltrán Cifuentes; Patricia, Durán Ospina; Luisa Fernanda, Corredor Arias.

    2008-04-01

    Full Text Available Introdução: Na Colômbia existem grupos de pesquisas em Leishmaniasis que têm somado esforços para a identificação do genoma da Leishmania spp. Como profs-sionais da saúde, é uma prioridade conecé-los para entender os mecanismos de resistência a fármacos. Métodos: As bases de dados empregadas para es [...] ta busca foram, entre outras: NCBI PubMed, MEDLINE, Science Direct, Nucleic Acids Research e Molecular and Biochemical Parasitology, publicações da revista Biomédica e de varias Universidades. Resultados: existem muitas espécies de vetores distribuídos em todo o país. As multi-resistências criadas por Leishmania sp. baseiam-se especialmente em proteínas de membrana e mutações pontuais no DNA do parasita e seus vetores. Conclusões: As técnicas de PCR deveriam ser implementadas na clínica para estudar resistências a fármacos. Os protocolos atuais contra Leishmaniasis não incluem novas alternativas. Os tratamentos imuno-moduladores são uma nova es-perança para o tratamento desta enfermidade re-emergente. Abstract in spanish Introducción: en Colombia existen grupos de investigación en Leishmaniasis que han aunado esfuerzos para lograr la identificación del genoma de la Leishmania spp. Como profesionales de la salud es una prioridad conocerlos para entender los mecanismos de resistencia a fármacos. Métodos: las bases de [...] datos empleadas para esta búsqueda fueron entre otras: NCBI PubMed, MEDLINE, Science Direct, Nucleic Acids Research y Molecular and Biochemical Parasitology, publicaciones de la revista Biomédica y de varias Universidades. Resultados: existen muchas especies de vectores distribuidos en todo el país. Las multiresistencias creadas por Leishmania sp. se basan especialmente en proteínas de membrana y mutaciones puntuales en el DNA del parásito y sus vectores. Conclusiones: las técnicas de PCR deberían ser implementadas en la clínica para estudiar resistencias a fármacos. Los protocolos actuales contra Leishmaniasis no incluyen nuevas alternativas. Los tratamientos inmunomoduladores son una nueva esperanza para el tratamiento de esta enfermedad re-emergente. Abstract in english Introduction: In Colombia there are research groups in Leishmaniasis that have joined forces to achieve the identification of the genome of Leishmania spp. As health professionals know this is a priority to understand the mechanisms of drug resistance. Methods: The databases used for this search wer [...] e among others: NCBI PubMed MEDLINE, Science Direct, Nucleic Acids Research and Biochemical and Molecular Parasitology, as a publication of the journal Biomedical and several universities. Results: There are many species and vectors distributed throughout the country. The multiresistents created by Leishmania spp. rely especially in membrane proteins and mutations in the DNA of the parasite and their delivery systems. Conclusions: The PCR techniques should be implemented at the clinic to study resistance to drugs. The current protocols against Leishmaniasis not include additional alternatives. The treatments with immunomodulators are the new hope for treating this re-emerging disease.

  2. Genes and Chromosomes of Leishmania infantum

    Scientific Electronic Library Online (English)

    Jose, María Requena; Manuel, Soto; Luis, Quijada; Carlos, Alonso.

    1997-11-01

    Full Text Available During recent years, several Leishmania infantum genes have been cloned and characterized. Here, we have summarized the available information on the gene organization and expression in this protozoan parasite. From a comparative analysis, the following outstanding features were found to be common to [...] most of the genes characterized: tandemly organized genes with conserved coding regions and divergent untranslated regions, polycistronic transcription and post-transcriptional regulation of gene expression. The analysis of chromosomes of L. infantum by pulsed-field electrophoresis showed the existence of both size and number polymorphisms such that each strain has a distinctive molecular karyotype. Despite this variability, highly conserved physical linkage groups exists among different strains of L. infantum and even among Old World Leishmania species. Gene mapping on the L. infantum molecular karyotype evidenced a bias in chromosomal distribution of, at least, the evolutionary conserved genes

  3. Structure of tyrosine aminotransferase from Leishmania infantum

    OpenAIRE

    Moreno, M. A.; Abramov, A.; Alonso Ayala, Ana Mari?a; Zhang, S.; Alcolea, Pedro J.; Edwards, T.; Lorimer, D.; Myler, P. J.; Larraga, Vicente

    2014-01-01

    The trypanosomatid parasite Leishmania infantum is the causative agent of visceral leishmaniasis (VL), which is usually fatal unless treated. VL has an incidence of 0.5 million cases every year and is an important opportunistic co-infection in HIV/AIDS. Tyrosine aminotransferase (TAT) has an important role in the metabolism of trypanosomatids, catalyzing the first step in the degradation pathway of aromatic amino acids, which are ultimately converted into their corresponding l-2-oxoacids. Unl...

  4. Plants used in the treatment of leishmanial ulcers due to Leishmania (Viannia) braziliensis in an endemic area of Bahia, Brazil

    Scientific Electronic Library Online (English)

    Flávio, França; Ednaldo L., Lago; Philip D., Marsden.

    1996-06-01

    Full Text Available Este trabalho relata as plantas usadas no tratamento da leishmaniose cutânea, causada por Leishmania (Viannia) braziliensis (L(V)b), na população rural da faixa litorânea produtora de cacau do estado da Bahia, Brasil. Um inquérito realizado entre 100 pacientes, identificou 49 espécies de plantas usa [...] das para tratar úlceras de pele causadas por esta espécie de Leishmânia. As principais plantas usadas foram o cajueiro-branco (Anacardium occidentale - Anacardiaceae) usado por 65% da população, a folha-fogo (Clidemia hirta - Melastomataceae) 39%, a alfavaca-grossa (Plectranthus amboinicus - Lamiaceae) 33%, o mastruz (Chenopodium ambrosioides - henopodiaceae) 31%, a erva-de-santa-maria (Solanum americanum - Solanaceae) 25% e a transagem (Plantago major - Plantaginaceae) 2%. Abstract in english This paper records the plants used in the treatment of cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis (L(V)b) among the rural population of a cocoa- producing coastal area of Bahia state, Brazil. An enquiry conducted among a hundred patients identified 49 plant species used to trea [...] t skin ulceration caused by this Leishmania species. The principal plants used are caju-branco (Anacardium occidentale - Anacardiaceae), used by 65% of the population, folha-fogo (Clidemia hirta - Melastomataceae) 39%, alfavaca-grossa (Plectranthus amboinicus - Lamiaceae) 33%, mastruz (Chenopodium ambrosioides - Chenopodiaceae) 31%, erva-de-santa-maria (Solatium americanum - Solanaceae) (25%) and transagem (Plantago major - Plantaginaceae.) 2%.

  5. Plants used in the treatment of leishmanial ulcers due to Leishmania (Viannia braziliensis in an endemic area of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Flávio França

    1996-06-01

    Full Text Available This paper records the plants used in the treatment of cutaneous leishmaniasis due to Leishmania (Viannia braziliensis (L(Vb among the rural population of a cocoa- producing coastal area of Bahia state, Brazil. An enquiry conducted among a hundred patients identified 49 plant species used to treat skin ulceration caused by this Leishmania species. The principal plants used are caju-branco (Anacardium occidentale - Anacardiaceae, used by 65% of the population, folha-fogo (Clidemia hirta - Melastomataceae 39%, alfavaca-grossa (Plectranthus amboinicus - Lamiaceae 33%, mastruz (Chenopodium ambrosioides - Chenopodiaceae 31%, erva-de-santa-maria (Solatium americanum - Solanaceae (25% and transagem (Plantago major - Plantaginaceae. 2%.Este trabalho relata as plantas usadas no tratamento da leishmaniose cutânea, causada por Leishmania (Viannia braziliensis (L(Vb, na população rural da faixa litorânea produtora de cacau do estado da Bahia, Brasil. Um inquérito realizado entre 100 pacientes, identificou 49 espécies de plantas usadas para tratar úlceras de pele causadas por esta espécie de Leishmânia. As principais plantas usadas foram o cajueiro-branco (Anacardium occidentale - Anacardiaceae usado por 65% da população, a folha-fogo (Clidemia hirta - Melastomataceae 39%, a alfavaca-grossa (Plectranthus amboinicus - Lamiaceae 33%, o mastruz (Chenopodium ambrosioides - henopodiaceae 31%, a erva-de-santa-maria (Solanum americanum - Solanaceae 25% e a transagem (Plantago major - Plantaginaceae 2%.

  6. Clonal variation within a mucosal isolate derived from a patient with Leishmania (Viannia braziliensis infection Variação clonal de um isolado derivado de um paciente com infecção mucosa pela Leishmania (Viannia braziliensis

    Directory of Open Access Journals (Sweden)

    César Augusto Cuba-Cuba

    1991-10-01

    Full Text Available Three isolates over 5 years from a patient with persistent relapsing mucosal leishmaniasis due to Leishmania (Viannia braziliensis and 7 clones from one of these isolates were studied by zymodemes and scrodemes analysis. Results showed evidences of clonal phenotypic variation. Eight isoenzymes markers demonstrated clear differences on Cellulose Acetate (CA and thin starch gel electrophoresis. Also a panel of specific monoclonal antibodies showed such differences. Our observations provide additional evidence that Leishmania (Viannia braziliensis is composed by subpopulations of parasites with peculiar biochemical and antigenic characteristics.No transcurso de um período de 5 anos foram estudados 3 isolados de um paciente com leishmaniose mucosa recidivante causada pela Leishmania (Viannia braziliensis e 7 clones de um desses isolados. Este estudo foi feito pela análise dos serodemas e zimodemas. Os resultados indicaram a ocorrência de variações fenotípicas clonais. Oito marcadores isoenzimáticos demonstraram diferenças nos padrões eletroforéticos em Acetato de Celulose (AC, bem como em camada fina de amido. Da mesma forma foram consultadas diferenças em um painel de anticorpos monoclonais específicos e subespecíficos. Nossas observações indicam ainda que a Leishmania (Viannia braziliensis está composta por subpopulações de parasitas com características bioquímicas e antigênicas peculiares.

  7. A small heat shock protein is essential for thermotolerance and intracellular survival of Leishmania donovani.

    Science.gov (United States)

    Hombach, Antje; Ommen, Gabi; MacDonald, Andrea; Clos, Joachim

    2014-11-01

    Leishmania parasites must survive and proliferate in two vastly different environments - the guts of poikilothermic sandflies and the antigen-presenting cells of homeothermic mammals. The change of temperature during the transmission from sandflies to mammals is both a key trigger for the progression of their life cycle and for elevated synthesis of heat shock proteins, which have been implicated in their survival at higher temperatures. Although the functions of the main heat shock protein families in the Leishmania life cycle have been studied, nothing is known about the roles played by small heat shock proteins. Here, we present the first evidence for the pivotal role played by the Leishmania donovani 23-kDa heat shock protein (which we called HSP23), which is expressed preferentially during the mammalian stage where it assumes a perinuclear localisation. Loss of HSP23 causes increased sensitivity to chemical stressors and renders L. donovani non-viable at 37°C. Consequently, HSP23-null mutants are non-infectious to primary macrophages in vitro. All phenotypic effects could be abrogated by the introduction of a functional HSP23 transgene into the null mutant, confirming the specificity of the mutant phenotype. Thus, HSP23 expression is a prerequisite for L. donovani survival at mammalian host temperatures and a crucial virulence factor. PMID:25179594

  8. Leishmania major: Parasite Interactions Suggesting Sexuality

    Directory of Open Access Journals (Sweden)

    Sousa Maria Auxiliadora de

    1997-01-01

    Full Text Available In five experiments, Leishmania (Leishmania major (MRHO/SU/59/P-strain grew poorly when seeded in FYTS medium supplemented with 15% fetal calf serum, but presented several peculiar pairs of promastigotes diametrically opposed and attached at their posterior ends (5.8-13.5%. As seen in Giemsa-stained smears, a ring-like line and/or an enlargement, generally occurred at the parasite junction. A close proximity of nuclei, which sometimes were difficult to distinguish from each other, was also observed at this junction. Several of these pairs appeared to be composed of fused cells in which the nuclei could be apparently fused, as shown by fluorescence microscopy to detect ß-tubulin and DNA, and by scanning electron microscopy. Under other culture conditions these pairs were absent or occurred at very low rates (0.2-2.2%. Such pairs differ markedly from longitudinally dividing cells and resemble those described in two other Leishmania species, as well as in Herpetomonas megaseliae and Phytomonas davidi, suggesting steps of a putative sexual process

  9. Nematodes of Amazonian birds, with a description of Hoazinstrongylus amazonensis n.gen.n.sp. (Trichostrongylidae, Libyostrongylinae

    Directory of Open Access Journals (Sweden)

    R. Magalhães Pinto

    1985-06-01

    Full Text Available During recent studies of the parasites of birds from the Amazonian Regio, the following nematodes were recovered: Hoazinstrongylus amazonensis n.gen.n.sp. from Opisthocomus hoazin (Muller, 1776; Ascaridia columbae (Gmel., 1790 Travassos, 1913, from Leptotila r. rufaxilla (Richard & Bernard, 1712 representing a new host record; Inglisakis ibanezi Freitas, Vicente & Santos, 1969, Cyrnea (C. semilunaris (Molin, 1860 Seurat, 1914 and Thelazia digitata Travassos, 1918. A compelte description is restrained to the new genus and new species here proposed. The other known and well described species are listed and accounted.Durante recentes estudos dos parasitas de aves capturadas na Região Amazônica, foram identificadas as seguintes espécies de nematóides: Hoazinstrongylus amazonensis n.gen.n.sp, de Opisthocomus hoazin (Muller, 1776, Ascaridia columbae (Gmel., 1790 Travassos, 1912, de Leptotila r. rufaxilla (Richard & Bernard, 1712 que se constitui em um novo hospedeiro para a espécie, Inglisakis ibanezi Freitas, Vicente & Santos, 1969, Cyrnea (C. semilunaris (Molin, 1860 Seurat, 1914 e Thelazia digitata Travassos, 1918.

  10. Nematodes of Amazonian birds, with a description of Hoazinstrongylus amazonensis n.gen.n.sp. (Trichostrongylidae, Libyostrongylinae)

    Scientific Electronic Library Online (English)

    R. Magalhães, Pinto; Delir Corrêa, Gomes.

    1985-06-01

    Full Text Available Durante recentes estudos dos parasitas de aves capturadas na Região Amazônica, foram identificadas as seguintes espécies de nematóides: Hoazinstrongylus amazonensis n.gen.n.sp, de Opisthocomus hoazin (Muller, 1776), Ascaridia columbae (Gmel., 1790) Travassos, 1912, de Leptotila r. rufaxilla (Richard [...] & Bernard, 1712) que se constitui em um novo hospedeiro para a espécie, Inglisakis ibanezi Freitas, Vicente & Santos, 1969, Cyrnea (C.) semilunaris (Molin, 1860) Seurat, 1914 e Thelazia digitata Travassos, 1918. Abstract in english During recent studies of the parasites of birds from the Amazonian Regio, the following nematodes were recovered: Hoazinstrongylus amazonensis n.gen.n.sp. from Opisthocomus hoazin (Muller, 1776); Ascaridia columbae (Gmel., 1790) Travassos, 1913, from Leptotila r. rufaxilla (Richard & Bernard, 1712) [...] representing a new host record; Inglisakis ibanezi Freitas, Vicente & Santos, 1969, Cyrnea (C.) semilunaris (Molin, 1860) Seurat, 1914 and Thelazia digitata Travassos, 1918. A compelte description is restrained to the new genus and new species here proposed. The other known and well described species are listed and accounted.

  11. Qualidade espermática de sêmen de cães naturalmente infectados por Leishmania sp: / Semen quality of dogs naturally infected by Leishmania sp

    Scientific Electronic Library Online (English)

    É., Labat; J.T., Carreira; B.H., Matsukuma; M.T.A., Martins; V.M.F., Lima; S.R.M., Bomfim; S.H.V., Perri; M.B., Koivisto.

    2010-06-01

    Full Text Available Avaliaram-se alterações espermáticas associadas à infecção por leishmaniose no sêmen de cães naturalmente infectados, utilizando-se, durante oito semanas consecutivas, ejaculados de seis cães soronegativos e seis cães soropositivos. As amostras foram colhidas uma vez por semana e avaliadas quanto ao [...] volume, concentração, motilidade, vigor, morfologia espermática, integridade da cromatina, avaliação simultânea da integridade da membrana plasmática, acrossoma e potencial mitocondrial. Concomitantemente foram dosadas a proteína total do plasma seminal e sanguíneo. A leishmaniose visceral causou aumento dos defeitos maiores e menores nos espermatozoides dos animais acometidos pelo estágio moderado a severo da doença. Em estágios mais avançados da enfermidade, a integridade das membranas acrossomal e plasmática foi afetada negativamente. Não foi possível estabelecer um critério quanto à avaliação do potencial mitocondrial. A incidência de alterações morfológicas nos animais acometidos não promoveu aumento de injurias à cromatina. Todos os animais com leishmaniose apresentaram hiperproteinemia do sêmen. Abstract in english The spermatic changes associated with the natural infection in dogs by Leishmania sp was evaluated during eight consecutive weeks, using ejaculates of six seronegative and six seropositive dogs. The samples were collected once a week and evaluated for volume, concentration, motility, vigor, sperm mo [...] rphology, chromatin integrity, simultaneous evaluation of the plasmatic membrane integrity, acrosome, and mitochondrial potential. The total proteins of the seminal plasma and blood were measured. The visceral leishmaniasis caused increase of major and minor defects in spermatozoa of animals attacked by moderate to severe stages of the disease. In more advanced stages of the illness, the acrosomal and plasmatic membranes integrity was adversely affected. It was not possible to establish a pattern refering the evaluation of the mitochondrial potential. The incidence of morphological changes in the seropositive animals did not promote an increase of injuries to the chromatin. All animals with leishmaniasis presented hyperproteinemia of the semen.

  12. Qualidade espermática de sêmen de cães naturalmente infectados por Leishmania sp: Semen quality of dogs naturally infected by Leishmania sp

    Directory of Open Access Journals (Sweden)

    É. Labat

    2010-06-01

    Full Text Available Avaliaram-se alterações espermáticas associadas à infecção por leishmaniose no sêmen de cães naturalmente infectados, utilizando-se, durante oito semanas consecutivas, ejaculados de seis cães soronegativos e seis cães soropositivos. As amostras foram colhidas uma vez por semana e avaliadas quanto ao volume, concentração, motilidade, vigor, morfologia espermática, integridade da cromatina, avaliação simultânea da integridade da membrana plasmática, acrossoma e potencial mitocondrial. Concomitantemente foram dosadas a proteína total do plasma seminal e sanguíneo. A leishmaniose visceral causou aumento dos defeitos maiores e menores nos espermatozoides dos animais acometidos pelo estágio moderado a severo da doença. Em estágios mais avançados da enfermidade, a integridade das membranas acrossomal e plasmática foi afetada negativamente. Não foi possível estabelecer um critério quanto à avaliação do potencial mitocondrial. A incidência de alterações morfológicas nos animais acometidos não promoveu aumento de injurias à cromatina. Todos os animais com leishmaniose apresentaram hiperproteinemia do sêmen.The spermatic changes associated with the natural infection in dogs by Leishmania sp was evaluated during eight consecutive weeks, using ejaculates of six seronegative and six seropositive dogs. The samples were collected once a week and evaluated for volume, concentration, motility, vigor, sperm morphology, chromatin integrity, simultaneous evaluation of the plasmatic membrane integrity, acrosome, and mitochondrial potential. The total proteins of the seminal plasma and blood were measured. The visceral leishmaniasis caused increase of major and minor defects in spermatozoa of animals attacked by moderate to severe stages of the disease. In more advanced stages of the illness, the acrosomal and plasmatic membranes integrity was adversely affected. It was not possible to establish a pattern refering the evaluation of the mitochondrial potential. The incidence of morphological changes in the seropositive animals did not promote an increase of injuries to the chromatin. All animals with leishmaniasis presented hyperproteinemia of the semen.

  13. Inhibition of Phagolysosomal Biogenesis by the Leishmania Lipophosphoglycan

    OpenAIRE

    Desjardins, Michel; Descoteaux, Albert

    1997-01-01

    Whereas amastigotes of the protozoan parasite Leishmania proliferate inside acidic phagolysosomal vacuoles of the macrophage, vacuoles induced by Leishmania donovani promastigotes during initiation of infection are poorly characterized. Here, evidence is presented that interaction of these parasitophorous vacuoles with endocytic organelles is very limited. In contrast, vacuoles formed around L. donovani mutants lacking the cell surface lipophosphoglycan (LPG) fuse extensively with endosome...

  14. Detection of Leishmania donovani and L. tropicain Ethiopian wild rodents.

    Czech Academy of Sciences Publication Activity Database

    Kassahun, A.; Sádlová, J.; Dvo?ák, V.; Koš?álová, T.; Rohoušová, I.; Frynta, D.; Aghová, Tatiana; Yasur-Landau, D.; Lemma, W.; Hailu, A.; Baneth, G.; Warburg, A.; Volf, P.; Votýpka, J.

    2015-01-01

    Ro?. 145, May 2015 (2015), s. 39-44. ISSN 0001-706X R&D Projects: GA ?R GAP506/10/0983 Institutional support: RVO:68081766 Keywords : Leishmania donovani * Leishmania tropica * Phlebotomine sand fly * Rodents * kDNA * ITS1 Subject RIV: EG - Zoology Impact factor: 2.519, year: 2013

  15. An improved purification procedure for Leishmania RNA virus (LRV)

    Scientific Electronic Library Online (English)

    Marcos Michel de, Souza; Livia Regina, Manzine; Marcos Vinicius G. da, Silva; Jefferson, Bettini; Rodrigo Vilares, Portugal; Angela Kaysel, Cruz; Eurico, Arruda; Otavio Henrique, Thiemann.

    2014-06-01

    Full Text Available Leishmania RNA Virus (LRV, Totiviridae) infect Leishmania cells and subvert mice immune response, probably promoting parasite persistence, suggesting significant roles for LRV in host-parasite interaction. Here we describe a new LRV1-4 purification protocol, enabling capsid visualization by negative [...] ly stained electron microscopy representing a significant contribution to future LRV investigations.

  16. Wild gorillas as a potential reservoir of Leishmania major.

    Science.gov (United States)

    Hamad, Ibrahim; Forestier, Claire-Lise; Peeters, Martine; Delaporte, Eric; Raoult, Didier; Bittar, Fadi

    2015-01-15

    Vector-borne parasites of the genus Leishmania are responsible for severe human diseases. Cutaneous leishmaniasis, a common form of the disease, is most often caused by the transmission of Leishmania major to humans by female phlebotomine sand ?ies. Apes are increasingly being seen as a source of zoonotic diseases, including malaria and rickettsiosis. To examine whether gorillas harbor Leishmania species, we screened fecal samples from wild western lowland gorillas (Gorilla gorilla gorilla) in Cameroon for the presence of these pathogens. Of 91 wild gorilla fecal samples, 12 contained Leishmania parasites, and 4 contained phlebotomine sand fly vectors. The molecular identity was determined by running 3 different polymerase chain reaction tests for detection of L. major. Next, fluorescence in situ hybridization was performed to visualize L. major parasites in fecal samples from the gorillas. Both promastigote and amastigote forms of the parasite were found. This work strongly suggests that wild gorillas carry pathogenic Leishmania parasites. PMID:25001460

  17. On Leishmania enriettii and Other Enigmatic Leishmania Species of the Neotropics

    Directory of Open Access Journals (Sweden)

    Ralph Lainson

    1997-05-01

    Full Text Available There are 20 named species of the genus Leishmania at present recognized in the New World, of which 14 are known to infect man. The present paper discusses the biological, biochemical and ecological features, where known, of six species which have not till now been found to cause human leishmaniasis; namely, Leishmania (Leishmania enriettii, L. (L. hertigi, L. (L. deanei, L. (L. aristidesi, L. (L. forattinii and L. (Viannia equatorensis. A protocol is suggested for attempts to discover the natural mammalian host(s and sandfly vector of L. (L. enriettii. Doubt is cast on the validity of the species L. herreri, described in Costa Rican sloths. Following the concensus of opinion that modern trypanosomatids derive from monogenetic intestinal flagellates of arthropods, phlebotomine sandflies are best regarded as the primary hosts of Leishmania species, with mammals acting as secondary hosts providing a source of parasites for these insects. There are probably natural barriers limiting the life-cycle of most leishmanial parasites to specific sandfly vectors

  18. Identification and distribution of New World Leishmania species characterized by serodeme analysis using monoclonal antibodies.

    Science.gov (United States)

    Grimaldi, G; David, J R; McMahon-Pratt, D

    1987-03-01

    Five hundred thirty stocks of Leishmania isolated from human and domestic and wild reservoir hosts, representing a wide geographic distribution of endemic foci of American cutaneous (ACL) and visceral leishmaniases (AVL) were characterized and identified at species and/or subspecies levels based on their reactivity to a cross-panel of specific monoclonal antibodies using a radioimmune binding assay. This study confirms and extends our preliminary results on the high specificity of some of these monoclonals for the L. braziliensis, L. mexicana, and L. donovani complexes. This study also demonstrates the relative stability of these molecular markers and the general usefulness of the method for parasite identification. Two hundred ninety-two of 420 isolates of ACL were classified as members of the L. braziliensis complex. Two hundred twenty-seven were L. b. braziliensis; these showed the widest geographical distribution (Brazil: Amazonas, Bahia, Ceara, Espirito Santo, Goias, Minas Gerais, Para, Paraiba, Rio de Janeiro, and Sao Paulo; Honduras: Santa Barbara and Yoko; Peru: Ancash, Piura, and Ucayali; and Venezuela: Cojedes, Distrito Federal, Lara, Portuguesa, Vale Hondo, Yaracuy, and Zulia). Forty-one stocks were identified as L. b. guyanensis (from North Brazil: Amazonas, Amapa, Para, and Rondonia). Twenty-one stocks were identified as L. b. panamensis (from Costa Rica: Alajuela, Guanacasten, Limon, Puntarenas, and San Jose; and Honduras: El Paraiso, and Olancho). Out of 128 isolates classified as members of the L. mexicana complex, 74 were differentiated as L. m. amazonensis (from Bolivia; Brazil: Amazonas, Bahia, Ceara, Goias, Maranhao, Mato Grosso do Norte, and Para; Peru: Pasco Forest and Van Humboldt; and Venezuela: Carabobo, Guarico, and Merida). Forty-four stocks were identified as L. m. venezuelensis (from Venezuela: Lara). Six stocks were L. m. mexicana (from Belize; and Mexico: Campeche [corrected] and Quintana Roo, Yucatan). One hundred ten isolates from AVL were identified as L. donovani chagasi (from Brazil: Bahia, Ceara, Maranhao, Minas Gerais, Mato Grosso do Sul, Piaui, Rio de Janeiro, and Sergipe; and Honduras: Valle). The implications of these results with respect to both the clinical and epidemiological data (including the detection of seven unusual characterized stocks) are discussed. PMID:3826486

  19. Lutzomyia longipalpis naturally infected by Leishmania (L.) chagasi in Várzea Grande, Mato Grosso State, Brazil, an area of intense transmission of visceral leishmaniasis / Lutzomyia longipalpis naturalmente infectado por Leishmania (L.) chagasi em Várzea Grande, Mato Grosso, Brasil, uma área de transmissão intensa de leishmaniose visceral

    Scientific Electronic Library Online (English)

    Nanci A., Missawa; Érika Monteiro, Michalsky; Consuelo Latorre, Fortes-Dias; Edelberto, Santos Dias.

    2010-12-01

    Full Text Available A leishmaniose visceral americana (LVA) é causada por parasitos pertencentes ao gênero Leishmania (Trypanosomatidae) e transmitida ao homem através da picada de certas espécies de flebotomíneos, previamente infectados. Neste trabalho, investigamos o índice de infecção natural de Lutzomyia longipalpi [...] s, principal vetor da LVA no Brasil, em Várzea Grande, Estado do Mato Grosso. De julho de 2004 a junho de 2006, foram feitas capturas de flebotomíneos em áreas peridomésticas utilizando armadilhas de luz CDC. Foram capturadas 420 espécimens de Lu. longipalpis. Quarenta e dois grupos, formados por 10 espécimens de Lu. longipalpis cada um, foram submetidos à extração de DNA genômico e amplificação por PCR (reação em cadeia da polimerase). DNA de Leishmania spp. foi detectado em 3 dos 42 grupos testados, resultando em um índice mínimo de infecção de 0,71%. A análise de polimorfismos de fragmentos de restrição (RFLP) indicou Leishmania (L.) chagasi como a espécie infectante nos grupos positivos. Abstract in english The American visceral leishmaniasis (AVL) is caused by parasites belonging to the genus Leishmania (Trypanosomatidae) and is transmitted to humans through the bite of certain species of infected phlebotomine sand flies. In this study, we investigated the natural infection ratio of Lutzomyia longipal [...] pis, the main vector species of AVL in Brazil, in Várzea Grande, Mato Grosso State. Between July 2004 and June 2006, phlebotomine sand flies were captured in peridomestic areas using CDC light-traps. Four hundred and twenty (420) specimens of Lu. longipalpis were captured. 42 pools, containing 10 specimens of Lu. longipalpis each, were used for genomic DNA extraction and PCR (polymerase chain reaction) amplification. Leishmania spp. DNA was detected in three out of the 42 pools tested, resulting in a minimal infection ratio of 0.71%. Restriction fragment length polymorphism (RFLP) analysis indicated that Leishmania (L.) chagasi was the infective agent in the positive pools.

  20. Charaterization of Leishmania major Friedlin Telomeric Terminus

    Scientific Electronic Library Online (English)

    Miguel Angel, Chiurillo; José Luis, Ramírez.

    2002-04-01

    Full Text Available Here we have characterized Leishmania major (Friedlin) telomeric terminus (the very end) using recombinants obtained by a vector-adaptor cloning protocol. As in L. donovani, the last nine nucleotides of L. major terminus are 5'-GGTTAGGGT-OH 3', differing from Trypanosoma cruzi and T. brucei terminus [...] 5'GGGTTAGGG-OH 3', thus indicating that these sequences are genus specific. We have also made a comparative analysis between L. major and L. donovani telomere-associated sequences, and described a novel non-repeated telomeric associated sequence common to L. major low molecular weight chromosomal bands.

  1. Pathology of dogs in Campo Grande, MS, Brazil naturally co-infected with Leishmania infantum and Ehrlichia canis / Patologia de cães naturalmente coinfectados por Leishmania infantum e Ehrlichia canis em Campo Grande, MS, Brasil

    Scientific Electronic Library Online (English)

    Gisele Braziliano, Andrade; Wanessa Teixeira Gomes, Barreto; Luciana Ladislau dos, Santos; Laura Raquel Rios, Ribeiro; Gabriel Carvalho de, Macedo; Keyla Carstens Marques de, Sousa; Marcos Rogério, André; Rosangela Zacarias, Machado; Heitor Miraglia, Herrera.

    2014-12-01

    Full Text Available A infecção simultânea por parasitas de diferentes espécies pode resultar em alterações imprevisíveis. O presente estudo avaliou a patologia de cães naturalmente coinfectados por Leishmania infantum e Ehrlichia canis. A saúde dos cães foi investigada pelas análises histopatológicas, hematológicas e b [...] ioquímicas de 21 cães infectados somente por L. infantum e 22 cães coinfectados por L. infantum e E. canis. Observou-se uma reação inflamatória crônica, predominantemente linfohistioplasmocítica, na pele dos dois grupos. A plasmocitose, encontrada nos tecidos linfóides, provavelmente estava relacionada com a hipergamaglobulinemia observada em todos os cães amostrados. A desorganização da matriz extracelular da derme da região inguinal e da orelha, demonstrada pela substituição das fibras de colágeno espessas por fibras finas, foi relacionada com o grau de reação inflamatória, independente da presença de parasitas. Ainda, observamos duas vezes mais animais do grupo coinfectado apresentando formas amastigotas na pele de orelha pela histopatologia comparado ao número de cães infectados apenas por Leishmania, tornando-os desta forma mais infectivos aos vetores. Nossos resultados ressaltam que a saúde de cães coinfectados estava severamente comprometida devido aos altos níveis de proteína plasmática total, globulinas, fosfatase alcalina, creatina quinase e anemia acentuada. Abstract in english Different parasites that commonly occur concomitantly can influence one another, sometimes with unpredictable effects. We evaluated pathological aspects of dogs naturally co-infected with Leishmania infantum and Ehrlichia canis. The health status of the dogs was investigated based on histopathologic [...] al, hematological and biochemical analyses of 21 animals infected solely with L. infantum and 22 dogs co- infected with L. infantum and E. canis. The skin of both groups showed chronic, predominantly lymphohistioplasmacytic inflammatory reaction. The plasmacytosis in the lymphoid tissues was likely related with the hypergammaglobulinemia detected in all the dogs. The disorganization of extracellular matrix found in the reticular dermis of the inguinal region and ear, characterized by the substitution of thick collagen fibers for thin fibers, was attributed to the degree of inflammatory reaction, irrespective of the presence of parasites. In addition, the histopathological analysis revealed that twice as many dogs in the co-infected group presented Leishmania amastigotes in the ear skin than those infected solely with Leishmania, increasing the possibility of becoming infected through sand fly vectors. Our findings highlight the fact that the health of dogs infected concomitantly with L. infantum and E. canis is severely compromised due to their high levels of total plasma protein, globulins, alkaline phosphatase and creatine kinase, and severe anemia.

  2. Proteomic Approach for Characterization of Immunodominant Membrane-Associated 30- to 36-Kilodalton Fraction Antigens of Leishmania infantum Promastigotes, Reacting with Sera from Mediterranean Visceral Leishmaniasis Patients

    OpenAIRE

    Kamoun-Essghaier, Sayda; Guizani, Ikram; Strub, Jean Marc; Dorsselaer, Alain; Mabrouk, Kamel; Ouelhazi, Lazhar; Dellagi, Koussay

    2005-01-01

    The aim of the present study was to identify and characterize proteins of a 30- to 36-kDa fraction of Leishmania infantum promastigote membranes previously shown to be an immunodominant antigen(s) in Mediterranean visceral leishmaniasis (MVL) and a consistent and reliable serological marker of this disease. By the first approach, Coomassie-stained protein bands (32- and 33-kDa fractions) that specifically reacted by immunoblotting with sera from MVL patients were excised from the gel and subm...

  3. Pesquisa de infecção natural de flebotomíneos por Leishmania, no Estado do Paraná / Research of natural infection of phlebotomines for Leishmania, in the State of Paraná

    Scientific Electronic Library Online (English)

    Herintha Coeto, Neitzke; Regiane Bertin de Lima, Scodro; Kárin Rosi Reinhold de, Castro; Alessandra de Cássia Dias, Sversutti; Thaís Gomes Verzignassi, Silveira; Ueslei, Teodoro.

    2008-02-01

    Full Text Available A leishmaniose tegumentar americana tem sido notificada em todos os estados do Brasil e no Paraná essa doença é endêmica. O objetivo deste trabalho foi detectar a infecção natural de flebotomíneos para verificar a competência vetorial destes insetos e a identificação da espécie parasitária. Os flebo [...] tomíneos foram coletados com armadilhas de Falcão e Shannon, nos municípios de Doutor Camargo, Fênix e Mandaguari, de novembro de 2005 a agosto de 2006. Coletaram-se 12.930 flebotomíneos, dos quais 2.487 fêmeas foram dissecadas e destes 1.230 fêmeas foram submetidas à reação em cadeia da polimerase. Pelo método da dissecação, foi detectada uma fêmea de Nyssomyia whitmani com infecção natural por flagelados e pela reação em cadeia da polimerase não se detectou a presença de DNA de Leishmania em nenhuma das fêmeas. Apesar de não ter sido detectada a infecção natural de Nyssomyia neivai nas localidades em apreço e ainda que os requisitos de incriminação vetorial não tenham sido atendidos, não se deve negligenciar o potencial vetorial desta espécie. Abstract in english American cutaneous leishmaniasis has been reported in all Brazilian states and in the Paraná this disease is endemic. The objective of this work was to detect natural infections in phlebotomines to verify the vector competence of these insects and the identification of the parasite species. Phleboto [...] mines were collected using Falcão and Shannon traps, in the municipalities of Doutor Camargo, Fênix and Mandaguari, between November 2005 and August 2006. from 12,930 phlebotomines were collected, 2,487 females were dissected and 1,230 dissected females had been submitted to polymerase chain reaction. Flagellates were detected in a female Nyssomyia whitmani that had been dissected and for polymerase chain reaction failed to detect Leishmania DNA in any females. Even though flagellates were not detected in Nyssomyia neivai it should still be considered as a potencial vector.

  4. The spiny rat Proechimys guyannensis (Rodentia: Echimydae) fails to respond to intradermal inoculation with Leishmania (Viannia) braziliensis / O rato espinhoso Proechimys guyannensis (Rodentia: Echimydae) falhou para inoculação intradérmica com Leishmania (Viannia) braziliensis.

    Scientific Electronic Library Online (English)

    Stela Rechinelli, PASSOS; Ana Paula, MADUREIRA; Sayanne Luns Hatum de, ALMEIDA; Marcos Santos, ZANINI.

    2015-06-01

    Full Text Available A leishmaniose é uma doença de ocorrência mundial causada por protozoários do gênero Leishmania. No Brasil, a Leishmania (Viannia) braziliensis é o principal parasita responsável pela leishmaniose tegumentar americana. Os principais hospedeiros deste protozoário são pequenos mamíferos selvagens em p [...] articular marsupiais e roedores. O objetivo deste estudo foi avaliar o papel do rato espinhoso Proechimys guyannensis (Rodentia: Echimydae) no ciclo da leishmaniose tegumentar americana. Para isto, formas promastigotas (estágio flagelado) de Leishmania (Viannia) braziliensis foram inoculadas em sete ratos espinhosos (Proechimys guyannensis). Após a inoculação intradérmica no pavilhão auricular, focinho e área plantar, os ratos foram monitorizados durante 180 dias. Amostras de tecido colhidas aos 90 e 180 dias dos ratos revelaram-se negativas para a presença de material genético do parasita. Após eutanásia, tecidos coletados dos ratos também falharam para crescimento em meio de cultura demonstrando que não houve infecção. Estes resultados demonstram que o rato espinhoso não tem papel no ciclo da leishmaniose tegumentar americana causada por L. (V.) braziliensis. Abstract in english Leishmaniasis a disease of worldwide occurrence is caused by protozoa of the Leishmania genus. In Brazil, Leishmania (Viannia) braziliensis is the main parasite responsible for the American cutaneous leishmaniasis. Main hosts of this protozoa are small wild mammals particularly marsupials and rodent [...] s. The aim of this study was to evaluate if spiny rat Proechimys guyannensis (Rodentia: Echimydae) has role in the cycle of the American cutaneous leishmaniasis caused by L. (V.) braziliensis. Thus, promastigotes (the flagellate stage) of Leishmania (Viannia) braziliensis were used to inoculate seven spiny rats (Proechimys guyannensis). After inoculated intradermal at the ear pinna, nose and plantar pad, the rats were monitored for 180 days. Tissue samples collected at 90 and 180 days from the rats proved to be negative for the presence of genetic material from the parasite. After euthanasia, the protozoa also failed to growth in culture medium containing tissue samples collected from the rats showing that there was no infection. These results fail to prove that spiny rat has a role in the cycle of the American cutaneous leishmaniasis caused by L. (V.) braziliensis.

  5. DISTINCT CELLULAR MIGRATION INDUCED BY Leishmania infantum chagasi AND SALIVA FROM Lutzomyia longipalpis IN A HEMORRHAGIC POOL MODEL / Migração celular distinta induzida por Leishmania infantum chagasi e saliva de Lutzomyia longipalpis em um modelo de pool hemorrágico

    Scientific Electronic Library Online (English)

    Camila Oliveira, Vasconcelos; Zirlane C. Branco, Coelho; Cristina de Souza, Chaves; Clarissa Romero, Teixeira; Margarida M. Lima, Pompeu; Maria Jania, Teixeira.

    2014-01-01

    Full Text Available O recrutamento de uma população de células específicas após infecção por Leishmania pode influenciar o resultado da doença. A migração celular em resposta a Leishmania ou saliva do vetor tem sido reportada utilizando o modelo da bolsa de ar subcutânea, entretanto, a migração celular induzida por Lei [...] shmania associada com o sangue do hospedeiro e saliva do vetor neste modelo ainda não foi descrita. Neste trabalho foi investigada a migração celular no modelo da bolsa de ar subcutânea em hamster após a estimulação com a combinação de L. chagasi, sangue do hospedeiro e saliva de Lutzomyia longipalpis. A migração induzida por saliva foi três vezes maior do que a induzida por L. chagasi sozinha. Adicionalmente, L. chagasi associada com sangue e saliva induziu significativamente ainda mais leucócitos no exsudato inflamatório do que o estímulo com Leishmania sozinha. L. chagasi recrutou uma população de células distintas, no entanto, a maioria dessas células parece não ter migrado para o exsudato inflamatório, permanecendo no tecido da bolsa de ar. Estes resultados indicam que L. chagasi pode reduzir o acúmulo de leucócitos para o local inicial da infecção e que quando associada à saliva do vetor e na presença de componentes do sangue aumenta o influxo de mais neutrófilos do que macrófagos, sugerindo que o parasito desenvolveu uma estratégia para minimizar a resposta inflamatória inicial, permitindo uma progressão ilimitada dentro do hospedeiro. Este trabalho reforça a importância de mais estudos sobre os componentes da saliva dos vetores das leishmanioses no processo de transmissão e no estabelecimento da infecção. Abstract in english Recruitment of a specific cell population after Leishmania infection can influence the outcome of the disease. Cellular migration in response to Leishmania or vector saliva has been reported in air pouch model, however, cellular migration induced by Leishmania associated with host's blood and vector [...] saliva in this model has not been described. Herein we investigated cellular migration into air pouch of hamster after stimulation with combination of L. chagasi and host's blood and Lutzomyia longipalpis saliva. Migration induced by saliva was 3-fold more than those induced by L. chagasi alone. Additionally, L. chagasi associated with blood and saliva induced significantly even more leukocytes into air pouch than Leishmania alone. L. chagasi recruited a diverse cell population; however, most of these cells seem to have not migrated to the inflammatory exudate, remaining in the pouch lining tissue. These results indicate that L. chagasi can reduce leukocyte accumulation to the initial site of infection, and when associated with vector saliva in the presence of blood components, increase the influx of more neutrophils than macrophages, suggesting that the parasite has developed a strategy to minimize the initial inflammatory response, allowing an unlimited progression within the host. This work reinforces the importance of studies on the salivary components of sand fly vectors of leishmaniasis in the transmission process and the establishment of the infection.

  6. Cloning of Leishmania Major P4 Gene

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    Minoo Shaddel

    2008-01-01

    Full Text Available Objective: Leishmania major P4 gene is normally expressed during amastigote form ofthe parasite and can be good candidate for producing an effective vaccine. In this study wecloned this gene in suitable vector (pQE-30 for further vaccine preparation studies.Materials and Methods: Leishmania promastigotes were grown in N.N.N.medium and culturein RPMI 1640 cell culture medium. Total genomic DNA was extracted by centrifugationof promastigotes. The pellet was suspended in lysis buffer and followed by boiling method.PCR was carried out using P4 gene specific primers. PCR product was detected by agarosgel electrophoresis and cloned into Bluescript plasmid via T/A cloning method. Reactionwas transformed into XL1- Blue competent cell and recombinant plasmid screened usingagar plate contained X-gal and IPTG. The product was extracted, digested by restrictionenzyme and electrophoresed on agarose gel.Results: Plasmid was extracted and cloned gene was released by restriction enzyme andsubcloned into pQE-30 expression vector.Conclusion: This construct is ready for protein expression in in-vitro.

  7. Cyclic nucleotide specific phosphodiesterases of Leishmania major

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    Linder Markus

    2006-03-01

    Full Text Available Abstract Background Leishmania represent a complex of important human pathogens that belong to the systematic order of the kinetoplastida. They are transmitted between their human and mammalian hosts by different bloodsucking sandfly vectors. In their hosts, the Leishmania undergo several differentiation steps, and their coordination and optimization crucially depend on numerous interactions between the parasites and the physiological environment presented by the fly and human hosts. Little is still known about the signalling networks involved in these functions. In an attempt to better understand the role of cyclic nucleotide signalling in Leishmania differentiation and host-parasite interaction, we here present an initial study on the cyclic nucleotide-specific phosphodiesterases of Leishmania major. Results This paper presents the identification of three class I cyclic-nucleotide-specific phosphodiesterases (PDEs from L. major, PDEs whose catalytic domains exhibit considerable sequence conservation with, among other, all eleven human PDE families. In contrast to other protozoa such as Dictyostelium, or fungi such as Saccharomyces cerevisiae, Candida ssp or Neurospora, no genes for class II PDEs were found in the Leishmania genomes. LmjPDEA contains a class I catalytic domain at the C-terminus of the polypeptide, with no other discernible functional domains elsewhere. LmjPDEB1 and LmjPDEB2 are coded for by closely related, tandemly linked genes on chromosome 15. Both PDEs contain two GAF domains in their N-terminal region, and their almost identical catalytic domains are located at the C-terminus of the polypeptide. LmjPDEA, LmjPDEB1 and LmjPDEB2 were further characterized by functional complementation in a PDE-deficient S. cerevisiae strain. All three enzymes conferred complementation, demonstrating that all three can hydrolyze cAMP. Recombinant LmjPDEB1 and LmjPDEB2 were shown to be cAMP-specific, with Km values in the low micromolar range. Several PDE inhibitors were found to be active against these PDEs in vitro, and to inhibit cell proliferation. Conclusion The genome of L. major contains only PDE genes that are predicted to code for class I PDEs, and none for class II PDEs. This is more similar to what is found in higher eukaryotes than it is to the situation in Dictyostelium or the fungi that concomitantly express class I and class II PDEs. Functional complementation demonstrated that LmjPDEA, LmjPDEB1 and LmjPDEB2 are capable of hydrolyzing cAMP. In vitro studies with recombinant LmjPDEB1 and LmjPDEB2 confirmed this, and they demonstrated that both are completely cAMP-specific. Both enzymes are inhibited by several commercially available PDE inhibitors. The observation that these inhibitors also interfere with cell growth in culture indicates that inhibition of the PDEs is fatal for the cell, suggesting an important role of cAMP signalling for the maintenance of cellular integrity and proliferation.

  8. Preliminary phytochemical and antileishmanial studies of the ethanolic extracts of Pterodon pudescens / Estudos preliminares sobre a fitoquimica e a atividade anti-leishmania de extratos etanólicos de Pterodon pudescens

    Scientific Electronic Library Online (English)

    W.W., Arrais-Silva; P.S.G., Nunes; J.D., Carvalho; M.W., Brune; C., Arrais-Lima; C., Batalini.

    2014-09-01

    Full Text Available Antimoniais pentavalentes são a primeira escolha para o tratamento das leishmanioses humanas. No entanto, no interior brasileiro plantas tradicionais são usadas para o tratamento dessas lesões. De fato, recentes trabalhos tem relatado o potencial terapêutico de produtos naturais, especialmente deriv [...] ados de plantas. Neste estudo avaliamos a atividade leishmanicida de Pterodon pubescens, uma árvore nativa, distribuída pela região central brasileira e usada em infusões para tratamento de inflamações. Foi realizada a análise fitoquímica e o ensaio in vitro em macrófagos infectados com Leishmania amazonensis em concentrações de 150, 300, 450, 600 µg/ml do extrato etanólico de folhas de Pterodon pudescens (PPE) para comprovar o uso tradicional desta planta como terapia para as leishmanioses. Os testes fitoquímicos indicaram a presença de taninos catequímicos, flavonas, esteroides, triterpenoides, flavonoides e xantonas. Os ensaios biológicos revelaram que o PPE foi capaz de controlar a carga parasitária em macrófagos de maneira dose dependente. Estes resultados corroboram com o potencial terapêutico de compostos de Pterodon pudescens e, junto com sua ampla distribuição no Brasil, podem representar promissor agente leishmanicida. Abstract in english Pentavalent antimonials are the first choice for the treatment of human leishmaniasis. However in rural areas the traditional plants may be preferred for the treatment of lesions. In recent years a number of papers are published related to the natural products especially plant derivative with infect [...] ious diseases. The present work was undertaken to evaluate the antileishmanial activity of Pterodon pubescens which is a native tree widely distributed over the central region of Brazil and used in folk medicine as wine infusions to treat inflammatory disease. The phytochemical screening and the biological essay of ethanolic extract of Pterodon pudescens (PPE) leaves at the concentrations of 150, 300, 450, 600 µg/ml were tested in vitro in Leishmania amazonensis-infected macrophages to support its traditional medicinal use as a leishmaniasis remedy. Phytochemical screening of PPE has shown the presence of catechemical tannins, steroids, triterpenoids and flavonoids. The biological test suggests that PPE were found to control parasite burden of cell cultures in dose-dependent manner. These findings highlight the fact that the apparent potency of Pterodon pudescens compounds, together with their widely distribution over Latin America and Brazil, may represent a promising antileishmanial agent.

  9. Reconstrucción quirúrgica tras destrucción nasal por Leishmania Panamensis Surgical reconstruction after nasal destruction by Leishmania Panamensis

    Directory of Open Access Journals (Sweden)

    F. Vélez Bernal

    2013-03-01

    Full Text Available Algunas especies de Leishmania del subgénero Viannia, especialmente Leishmania braziliensis y Leishmania panamensis, pueden invadir la mucosa naso-orofaríngea al diseminarse por vía linfática y sanguínea a partir de una lesión cutánea y ocasionar lesiones en el tabique nasal, paladar blando, úvula, pilares amigdalinos, laringe, faringe, dorso nasal, labios y pómulos, que pueden conducir a la desfiguración. La mucosa más frecuentemente afectada es la del tabique nasal, principalmente en su parte anterior. La invasión de la mucosa puede ocurrir simultáneamente con lesiones cutáneas activas, aunque más frecuentemente aparecen 1 o 2 años después de la lesión en la piel; sin embargo, en el 16 % de los casos no hay antecedentes de lesiones cutáneas, lo que sugiere que con la picadura del insecto vector se produjo una infección primaria asintomática u oligosintomática y luego se produjo la diseminación del parasito a la mucosas. En este artículo presentamos 2 casos clínicos de leishmaniosis mucosa producidos por L. panamensis y los procedimientos quirúrgicos reconstructivos que se realizaron. Se hace además un recuento de los diagnósticos diferenciales en tejidos oronasales.Species of Leishmania of Viannia subgenus, mainly L. braziliensis and L. panamensis, may invade the nasooro-pharyngeal mucosal after spread from the skin lesion via lymph and blood, causing lesions in the nasal septum, soft palate, uvula, tonsillar pillars, larynx, pharynx, nasal dorsum, lips and cheeks. The mucosal membrane most frequently affected is the nasal septum, mainly in the anterior region. The invasion of mucosa may occur simultaneously with active skin lesions, but most often appear 1 or 2 years after the skin lesion; nevertheless, in 16 % of cases there is no history of skin lesions suggesting that the primary infection coursed with few symptoms and then was spread to mucosal membranes. In this article 2 cases of L panamensis mucosal leishmaniasis and the reconstructive surgery used are presented. A discussion of the differential diagnosis of oro-nasal tissues is also presented.

  10. Reconstrucción quirúrgica tras destrucción nasal por Leishmania Panamensis / Surgical reconstruction after nasal destruction by Leishmania Panamensis

    Scientific Electronic Library Online (English)

    F., Vélez Bernal; J.A., Vélez Trujillo; I.D., Vélez Bernal.

    2013-03-01

    Full Text Available Algunas especies de Leishmania del subgénero Viannia, especialmente Leishmania braziliensis y Leishmania panamensis, pueden invadir la mucosa naso-orofaríngea al diseminarse por vía linfática y sanguínea a partir de una lesión cutánea y ocasionar lesiones en el tabique nasal, paladar blando, úvula, [...] pilares amigdalinos, laringe, faringe, dorso nasal, labios y pómulos, que pueden conducir a la desfiguración. La mucosa más frecuentemente afectada es la del tabique nasal, principalmente en su parte anterior. La invasión de la mucosa puede ocurrir simultáneamente con lesiones cutáneas activas, aunque más frecuentemente aparecen 1 o 2 años después de la lesión en la piel; sin embargo, en el 16 % de los casos no hay antecedentes de lesiones cutáneas, lo que sugiere que con la picadura del insecto vector se produjo una infección primaria asintomática u oligosintomática y luego se produjo la diseminación del parasito a la mucosas. En este artículo presentamos 2 casos clínicos de leishmaniosis mucosa producidos por L. panamensis y los procedimientos quirúrgicos reconstructivos que se realizaron. Se hace además un recuento de los diagnósticos diferenciales en tejidos oronasales. Abstract in english Species of Leishmania of Viannia subgenus, mainly L. braziliensis and L. panamensis, may invade the nasooro-pharyngeal mucosal after spread from the skin lesion via lymph and blood, causing lesions in the nasal septum, soft palate, uvula, tonsillar pillars, larynx, pharynx, nasal dorsum, lips and ch [...] eeks. The mucosal membrane most frequently affected is the nasal septum, mainly in the anterior region. The invasion of mucosa may occur simultaneously with active skin lesions, but most often appear 1 or 2 years after the skin lesion; nevertheless, in 16 % of cases there is no history of skin lesions suggesting that the primary infection coursed with few symptoms and then was spread to mucosal membranes. In this article 2 cases of L panamensis mucosal leishmaniasis and the reconstructive surgery used are presented. A discussion of the differential diagnosis of oro-nasal tissues is also presented.

  11. Characterization and regulation of Leishmania major 3-hydroxy-3-methylglutaryl-CoA reductase

    DEFF Research Database (Denmark)

    Montalvetti, A; Pena Diaz, Javier

    2000-01-01

    In eukaryotes the enzyme 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase catalyses the synthesis of mevalonic acid, a common precursor to all isoprenoid compounds. Here we report the isolation and overexpression of the gene coding for HMG-CoA reductase from Leishmania major. The protein from Leishmania lacks the membrane domain characteristic of eukaryotic cells but exhibits sequence similarity with eukaryotic reductases. Highly purified protein was achieved by ammonium sulphate precipitation followed by chromatography on hydroxyapatite. Kinetic parameters were determined for the protozoan reductase, obtaining K(m) values for the overall reaction of 40.3+/-5.8 microM for (R,S)-HMG-CoA and 81.4+/-5.3 microM for NADPH; V(max) was 33.55+/-1.8 units x mg(-1). Gel-filtration experiments suggested an apparent molecular mass of 184 kDa with subunits of 46 kDa. Finally, in order to achieve a better understanding of the role of this enzyme in trypanosomatids, the effect of possible regulators of isoprenoid biosynthesis in cultured promastigote cells was studied. Neither mevalonic acid nor serum sterols appear to modulate enzyme activity whereas incubation with lovastatin results in significant increases in the amount of reductase protein. Western- and Northern-blot analyses indicate that this activation is apparently performed via post-transcriptional control.

  12. Leishmaniose causada por Leishmania viannia braziliensis (Lvb um caso de evolução atípica

    Directory of Open Access Journals (Sweden)

    Jackson Maurício Lopes Costa

    1988-06-01

    Full Text Available Os autores relatam o caso de uma criança portadora de Leishmaniose Tegumentar Americana causada por Leishmania braziliensis braziliensis que foi infectada durante a amamentação, desenvolvendo lesão infiltrativa e nodular nos lábios, com posterior disseminação para os seios da face, fossas nasais e pavilhão auricular e cuja evolução clinica pós-terapêutica caracterizou-se por períodos sucessivos de regressão e de reativação da lesão. Enfatizam a gravidade do caso, e as dificuldades terapêuticas com a utilização dos antimoniais pentavalentes, antimoniato-N-metil glucamina (Glucantime e o stibogluconato de sódio(Pentostam.The authors report a case of a child infected with Leishmania viannia braziliensis during breast feeding, who developed an infiltrated, granulomatous lesion of the lips, followed by dissemination to the face, nasal fossae and external ears. Post therapeutic clinical evolution was characterized by periods of regression and lesion reactivation. The seriousness of the case, and the therapeutic difficulties with the utilization of pentavalent antimonials, meglumine antimoniate (glucantime and sodium stibogluconate (Pentostam are discussed.

  13. Leishmaniose causada por Leishmania viannia braziliensis (Lvb) um caso de evolução atípica

    Scientific Electronic Library Online (English)

    Jackson Maurício Lopes, Costa; Kyola Costa, Vale; Flávio, França; Ednaldo L., Lago; Albino V., Magalhães; Philip D., Marsden; Raimunda N., Sampaio.

    1988-06-01

    Full Text Available Os autores relatam o caso de uma criança portadora de Leishmaniose Tegumentar Americana causada por Leishmania braziliensis braziliensis que foi infectada durante a amamentação, desenvolvendo lesão infiltrativa e nodular nos lábios, com posterior disseminação para os seios da face, fossas nasais e p [...] avilhão auricular e cuja evolução clinica pós-terapêutica caracterizou-se por períodos sucessivos de regressão e de reativação da lesão. Enfatizam a gravidade do caso, e as dificuldades terapêuticas com a utilização dos antimoniais pentavalentes, antimoniato-N-metil glucamina (Glucantime) e o stibogluconato de sódio(Pentostam). Abstract in english The authors report a case of a child infected with Leishmania viannia braziliensis during breast feeding, who developed an infiltrated, granulomatous lesion of the lips, followed by dissemination to the face, nasal fossae and external ears. Post therapeutic clinical evolution was characterized by pe [...] riods of regression and lesion reactivation. The seriousness of the case, and the therapeutic difficulties with the utilization of pentavalent antimonials, meglumine antimoniate (glucantime) and sodium stibogluconate (Pentostam) are discussed.

  14. Implications of a Neotropical Origin of the Genus Leishmania

    Directory of Open Access Journals (Sweden)

    Noyes Harry

    1998-01-01

    Full Text Available The hypothesis of a Neotropical origin of the Leishmania/Endotrypanum clade is reviewed. The position of the L. (Sauroleishmania external to the subgenus L. (Leishmania is not consistent with the Neotropical origin of the latter subgenus. It is suggested that this may be a consequence of a faster evolutionary rate in the L. (Sauroleishmania. The implications for the classsification of the phlebotomine sandflies of the hypothesis for a Neotropical origin of the Leishmania is also considered. The classification of Galati (1995 is proposed to be most consistent with the hypothesis of a Neotropical origin of the Leishmania, whilst classifications which place the New and Old World species in separate taxa are inconsistent with this hypothesis.

  15. In vitro evaluation of new terpenoid derivatives against Leishmania infantum and Leishmania braziliensis

    Scientific Electronic Library Online (English)

    Inmaculada, Ramírez-Macías; Clotilde, Marín; Rachid, Chahboun; Francisco, Olmo; Ibtisam, Messouri; Oscar, Huertas; María Jose, Rosales; Ramón, Gutierrez-Sánchez; Enrique, Alvarez-Manzaneda; Manuel, Sánchez-Moreno.

    2012-05-01

    Full Text Available The activity of five (1-5) abietane phenol derivatives against Leishmania infantum and Leishmania braziliensis was studied using promastigotes and axenic and intracellular amastigotes. Infectivity and cytotoxicity tests were performed with J774.2 macrophage cells using Glucantime as a reference drug [...] . The mechanisms of action were analysed by performing metabolite excretion and transmission electron microscopy ultrastructural studies. Compounds 1-5 were more active and less toxic than Glucantime. The infection rates and mean number of parasites per cell observed in amastigote experiments showed that derivatives 2, 4 and 5 were the most effective against both L. infantum and L. braziliensis. The ultrastructural changes observed in the treated promastigote forms confirmed that the greatest cell damage was caused by the most active compound (4). Only compound 5 caused changes in the nature and amounts of catabolites excreted by the parasites, as measured by ¹H nuclear magnetic resonance spectroscopy. All of the assayed compounds were active against the two Leishmania species in vitro and were less toxic in mammalian cells than the reference drug.

  16. A comparison of molecular markers to detect Lutzomyia longipalpis naturally infected with Leishmania (Leishmania) infantum

    Scientific Electronic Library Online (English)

    Kárita Cláudia, Freitas-Lidani; Iara J de, Messias-Reason; Edna Aoba Y, Ishikawa.

    2014-07-03

    Full Text Available The aim of the present study was to detect natural infection by Leishmania (Leishmania) infantum in Lutzomyia longipalpis captured in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this approach, it is unnecessary to previously dissect the sandfly specimens. DNA of 280 [...] Lu. longipalpis female specimens were extracted from the whole insects. PCR primers for kinetoplast minicircle DNA (kDNA), the mini-exon gene and the small subunit ribosomal RNA (SSU-rRNA) gene of Leishmania were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively. Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in 5.3% of the cases. These data show the importance of polymerase chain reaction as a tool for investigating the molecular epidemiology of visceral leishmaniasis by estimating the risk of disease transmission in endemic areas, with the kDNA primer representing the most reliable marker for the parasite.

  17. The role of phosphoglycans in Leishmania–sand fly interactions

    OpenAIRE

    Sacks, David L.; Modi, Govind; Rowton, Edgar; Späth, Gerald; Epstein, Linda; Salvatore J. Turco; Beverley, Stephen M.

    2000-01-01

    Leishmania promastigotes synthesize an abundance of phosphoglycans, either attached to the cell surface through phosphatidylinositol anchors (lipophosphoglycan, LPG) or secreted as protein-containing glycoconjugates. These phosphoglycans are thought to promote the survival of the parasite within both its vertebrate and invertebrate hosts. The relative contributions of different phosphoglycan-containing molecules in Leishmania–sand fly interactions were tested by using mutants specifically d...

  18. Leishmania development in sand flies: parasite-vector interactions overview

    OpenAIRE

    Dosta?lova?, Anna; Volf, Petr

    2012-01-01

    Leishmaniases are vector-borne parasitic diseases with 0.9 – 1.4 million new human cases each year worldwide. In the vectorial part of the life-cycle, Leishmania development is confined to the digestive tract. During the first few days after blood feeding, natural barriers to Leishmania development include secreted proteolytic enzymes, the peritrophic matrix surrounding the ingested blood meal and sand fly immune reactions. As the blood digestion proceeds, parasites need to bind to the midg...

  19. Preliminary study towards a novel experimental model to study localized cutaneous leishmaniasis caused bY Leishmania (Leishmania) mexicana Estudio preliminar sobre un nuevo y original modelo experimental de leishmaniosis cutánea localizada causada por Leishmania (Leishmania) mexicana

    OpenAIRE

    Erika Ivett Sosa-Bibiano; Nicole Raymonde Van Wynsberghe; Silvia Beatriz Canto-Lara; Fernando Jose Andrade-Narvaez

    2012-01-01

    There is not an experimental model of localized cutaneous leishmaniasis (LCL) caused by Leishmania (Leishmania) mexicana. The aim of the present study was to characterize the clinical and histological features of Peromyscus yucatanicus experimentally infected with L. (L.) mexicana. A total of 54 P. yucatanicus (groups of 18) were inoculated with 1x10(6) promastigotes of L. (L.) mexicana in the base of the tail. They were euthanized at three and six months post experimental infection. The cont...

  20. Cross-reactivity of antibodies in human infections by the kinetoplastid protozoa Trypanosoma cruzi, Leishmania chagasi and Leishmania (Viannia) braziliensis Reatividade cruzada de anticorpos em pacientes com infecções pelos protozoários Trypanosoma cruzi, Leishmania chagasi e Leishmania (Viannia) braziliensis

    OpenAIRE

    Ana de Cássia Vexenat; Jaime M. Santana; Teixeira, Antonio R. L.

    1996-01-01

    We have detected antibodies, in the sera of Chagas disease, Kala-azar and Mucocutaneous leishmaniasis patients, that bind multiple antigens shared between the three causative agents. The Chagas disease sera showed 98 to 100% positive results by ELISA when the Leishmania braziliensis and Leishmania chagasi antigens were used, respectively. The Kala-azar sera showed 100% positive results with Trypanosoma cruzi or L. braziliensis antigens by immunofluorescence assays. The antibodies in the sera ...

  1. Response of Leishmania chagasi promastigotes to oxidant stress.

    OpenAIRE

    Wilson, M. E.; K. A.; Andersen; Britigan, B E

    1994-01-01

    At the onset of infection, Leishmania promastigotes are phagocytized by mammalian macrophages. They must survive despite exposure to toxic oxidants such as hydrogen peroxide (H2O2) and superoxide (.O2-) generated during phagocytosis. We investigated the effects of these oxidants on Leishmania chagasi promastigotes and promastigote mechanisms for oxidant resistance. According to spin trapping and electron paramagnetic resonance spectrometry, .O2- could be generated by exposure of promastigotes...

  2. Phenylalanine hydroxylase (PAH) from the lower eukaryote Leishmania major

    OpenAIRE

    Lye, Lon-Fye; Kang, Song Ok; Nosanchuk, Joshua D.; Casadevall, Arturo; Beverley, Stephen M.

    2010-01-01

    Aromatic amino acid hydroxylases (AAAH) typically use tetrahydrobiopterin (H4B) as the cofactor. The protozoan parasite Leishmania major requires biopterin for growth and expresses strong salvage and regeneration systems to maintain H4B levels. Here we explored the consequences of genetic manipulation of the sole L. major phenylalanine hydroxylase (PAH) to explore whether it could account for the Leishmania H4B requirement. L. major PAH resembles AAAHs of other organisms, bearing eukaryotic-t...

  3. immune response in human leishmania infections Respuesta inmune en infecciones humanas por Leishmania spp

    Directory of Open Access Journals (Sweden)

    Sara María Robledo Restrepo

    2000-03-01

    Full Text Available This review summarizes relevant information about the immune response triggered during leishmaniosis, a disease of great importance from the epidemiological point of view, since it is endemic in Colombia and other countries. We emphasize on human leishmaniosis; nevertheless, some important findings in the murine model are also mentioned. This information allows to conclude that Leishmania infection is a complex and coordinated process, which includes adhesion and entrance of the parasite into the host cells and its survival inside them. Events that mediate the infection process may influence its result in terms of elimination of the parasite or development of the disease, through induction or not of an effective specific immune response which involves host cell activation and parasite destruction. La presente revisión tiene como objetivo resumir la información más relevante acerca de la respuesta inmune que se desencadena durante la leishmaniosis, una enfermedad de gran importancia desde el punto de vista epidemiológico dado que es endémica en Colombia y otros países. Aunque la respuesta inmune en la leishmaniosis es un tema que se ha estudiado ampliamente en las infecciones por especies de Leishmania del Viejo Mundo, particularmente Leishmania major y Leishmania donovani y en el modelo murino, la presente revisión hace énfasis en la leishmaniosis humana. Algunos hallazgos importantes en el modelo murino también se mencionan. La información contenida en la revisión, en su mayoría, proviene de publicaciones derivadas de investigaciones, las cuales se seleccionaron con base en la calidad del trabajo realizado y en los aportes de sus resultados en el avance del conocimiento sobre las infecciones en humanos. La síntesis de la información seleccionada nos permite concluir que la infección por Leishmania es un proceso complejo y coordinado que incluye la adherencia y entrada del parásito a la célula hospedera y su posterior supervivencia en el interior de la célula infectada. Los eventos que median el proceso de infección influyen en su resultado en términos de eliminación del parásito o desarrollo de la enfermedad, a través de la inducción o no de una respuesta inmune específica efectiva que lleve a la activación de la célula hospedera y la muerte y destrucción del parásito.

  4. Evidência de transmissão de leishmaniose visceral por Lutzomyia cruzi no município de Jaciara, Estado de Mato Grosso, Brasil / Evidence of transmission of visceral leishmaniasis by Lutzomyia cruzi in the municipality of Jaciara, State of Mato Grosso, Brazil

    Scientific Electronic Library Online (English)

    Nanci Akemi, Missawa; Márcia Aurélia Esser, Veloso; Giovana Belem Moreira Lima, Maciel; Érika Monteiro, Michalsky; Edelberto Santos, Dias.

    2011-02-01

    Full Text Available INTRODUÇÃO: O município de Jaciara foi classificado em 2003, como área de transmissão de leishmaniose visceral em situação de surto. O trabalho objetivou determinar evidência de transmissão de Leishmania (Leishmania) infantum chagasi por Lutzomyia cruzi no município de Jaciara, Estado de Mato Grosso [...] , Brasil. MÉTODOS: O município situa-se a 127km da capital Cuiabá e é um importante ponto de atração para os praticantes de eco-turismo. Fêmeas de Lutzomyia cruzi, capturadas com armadilha de CDC, foram dissecadas para confirmação da espécie e armazenadas a -20ºC em pools de 10 indivíduos para extração de DNA, PCR genérico, RFLP específico e eletroforese em gel de poliacrilamida. RESULTADOS: O levantamento entomológico demonstrou a ocorrência abundante de Lutzomyia cruzi e ausência de Lutzomyia longipalpis, principal vetora da Leishmania (Leishmania) infantum chagasi. Uma das três amostras analisadas apresentou banda característica de DNA de Leishmania (120pb) em PCR genérico. Para confirmação da espécie de Leishmania, na RFLP utilizaram-se controles positivos de Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis e Leishmania (Leishmania) infantum chagasi digeridas com enzima de restrição HaeIII. Constatou-se um padrão de bandas semelhante à Leishmania (Leishmania) infantum chagasi em uma amostra, confirmando a detecção de infecção natural de Leishmania (Leishmania) infantum chagasi em Lutzomyia cruzi. CONCLUSÕES: A ocorrência de casos humanos e cães positivos, a presença da Lutzomyia cruzi e a ausência de Lutzomyia longipalpis, bem como a detecção de infecção natural por Leishmania (Leishmania) infantum chagasi, evidenciam a participação de Lutzomyia cruzi na transmissão da leishmaniose visceral em Jaciara, Estado de Mato Grosso, Brasil. Abstract in english INTRODUCTION: The municipality of Jaciara was classified in 2003 as a transmission area for visceral leishmaniasis in outbreak situations. This study aimed to establish evidence of transmission of Leishmania (Leishmania) infantum chagasi by Lutzomyia cruzi in the municipality of Jaciara, State of Ma [...] to Grosso, Brazil. METHODS: This municipality is located 127 km from the state capital (Cuiabá) and is an important center for ecotourism practitioners. Females of Lutzomyia cruzi, captured using CDC traps, were dissected to confirm the species and stored at -20ºC in pools of 10 individuals for DNA extraction, generic PCR, specific RFLP and electrophoresis on polyacrylamide gel. RESULTS: The entomological survey showed abundant occurrence of Lutzomyia cruzi and absence of Lutzomyia longipalpis (the main vector for Leishmania (Leishmania) infantum chagasi). One of the three samples showed a characteristic DNA band from Leishmania (120 bp) in generic PCR. To confirm the Leishmania species via RFLP, positive controls for Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis and Leishmania (Leishmania) infantum chagasi digested with restriction enzyme HaeIII were used. A pattern of bands similar to Leishmania (Leishmania) infantum chagasi was found in one sample, thus confirming the detection of natural infection with Leishmania (Leishmania) infantum chagasi in Lutzomyia cruzi. CONCLUSIONS: The occurrences of positive cases in humans and dogs, the presence of Lutzomyia cruzi and the absence of Lutzomyia longipalpis together with the detection of natural infection with Leishmania (Leishmania) infantum chagasi, indicate that Lutzomyia cruzi participates in visceral leishmaniasis transmission in Jaciara, State of Mato Grosso, Brazil.

  5. Deficiency of Leishmania Phosphoglycans Influences the Magnitude but Does Not Affect the Quality of Secondary (Memory) Anti-Leishmania Immunity

    OpenAIRE

    Dong LIU; Okwor, Ifeoma; Mou, Zhirong; Beverley, Stephen M.; Uzonna, Jude E.

    2013-01-01

    Despite inducing very low IFN-? response and highly attenuated in vivo, infection of mice with phosphoglycan (PG) deficient Leishmania major (lpg2-) induces protection against virulent L. major challenge. Here, we show that mice infected with lpg2- L. major generate Leishmania-specific memory T cells. However, in vitro and in vivo proliferation, IL-10 and IFN-? production by lpg2- induced memory cells were impaired in comparison to those induced by wild type (WT) parasites. Interestingly, T...

  6. Antileishmanial activity of licochalcone A in mice infected with Leishmania major and in hamsters infected with Leishmania donovani.

    OpenAIRE

    Chen, M.(University of Florida, Gainesville, U.S.A.); Christensen, S B; Theander, T. G.; Kharazmi, A

    1994-01-01

    This study was designed to examine the antileishmanial activity of the oxygenated chalcone licochalcone A in mice and hamsters infected with Leishmania parasites. Intraperitoneal administration of licochalcone A at doses of 2.5 and 5 mg/kg of body weight per day completely prevented lesion development in BALB/c mice infected with Leishmania major. Treatment of hamsters infected with L. donovani with intraperitoneal administration of licochalcone A at a dose of 20 mg/kg of body weight per day ...

  7. Diagnosis of Leishmania (Leishmania) chagasi infection in dogs and the relationship with environmental and sanitary aspects in the municipality of Palmas, state of Tocantins, Brazil / Identificação de cães infectados por Leishmania (Leishmania) chagasi e sua relação com aspectos ambientais e sanitários no município de Palmas, estado do Tocantins, Brasil

    Scientific Electronic Library Online (English)

    Julio Gomes, Bigeli; Waldesse Piragé de, Oliveira Júnior; Natália Melquie Monteiro, Teles.

    2012-02-01

    Full Text Available INTRODUÇÃO: O estudo foi realizado com o objetivo de identificar, através da PCR, a presença da infecção por Leishmania (Leishmania) chagasi em cães no município de Palmas, no Estado do Tocantins, Brasil, de modo a elencar os hot spots de cães infectados no município e associar sua ocorrência a alte [...] rações ambientais marcantes nos locais de captura. MÉTODOS: O DNA foi extraído do sangue dos cães e as reações de PCR foram realizadas com os primers RV1/RV2. Após o screening da população estudada, foram detectadas as regiões do município que apresentavam as maiores ocorrências da infecção canina. Esses locais foram visitados, e parâmetros de distúrbio ecológico com origem antrópica foram avaliados. RESULTADOS: Algumas características importantes foram constantes entre as regiões visitadas, entre elas a baixa urbanização, inexistência de coleta pública de esgoto, coleta publica de lixo pouco abrangente, lotes vagos com vegetação alta, e matéria orgânica em decomposição, com destaque para criação de cães soltos, e aves nas residências. CONCLUSÕES: A metodologia adotada para screening da população se mostrou bastante eficiente, sobretudo na avaliação de um grande número de indivíduos em tempo reduzido, com alto grau de automatização. Os resultados apresentados indicam associação entre os parâmetros observados e a ocorrência da infecção em cães. O modelo apresentado no município é ideal para estudos do desenvolvimento da doença, bem como sua expansão, além da avaliação das medidas de controle adotadas para a leishmaniose visceral canina. Abstract in english INTRODUCTION: The aim of the present study was to identify the presence of Leishmania (Leishmania) chagasi infection in dogs in the City of Palmas, Tocantins, Brazil, using the PCR technique to list the hot spots of infected dogs in the city and associate their occurrence to significant environmenta [...] l changes at capture sites. METHODS: DNA was extracted from blood of dogs, and the PCR were performed with primers RV1/RV2. After screening the population studied, the regions of the city that had the highest occurrence of canine infection were detected. These sites were visited, and ecological parameters denoting anthropogenic disturbance were evaluated. RESULTS: Some important features were listed in the regions visited, such as low urbanization, lack of public collection of sewage, limited garbage collection, vacant lots with tall vegetation, decaying organic matter, and, most importantly, the occurrence of stray dogs and poultry in homes. CONCLUSIONS: The methodology for screening the population was very efficient, especially in evaluating a large number of individuals in a short time, with a high degree of automation. The results indicate an association between the observed parameters and the occurrence of infection in dogs. The model presented in the city is ideal for studies of disease progression and expansion and for the evaluation of control measures adopted for canine VL.

  8. Multifaceted Population Structure and Reproductive Strategy in Leishmania donovani Complex in One Sudanese Village

    OpenAIRE

    Rougeron, Virginie; Meeu?s, Thierry; Hide, Mallorie; Le Falher, Georges; Bucheton, Bruno; Dereure, Jacques; El-safi, Sayda; Dessein, Alain; Ban?uls, Anne-laure

    2011-01-01

    Leishmania species of the subgenus Leishmania and especially L. donovani are responsible for a large proportion of visceral leishmaniasis cases. The debate on the mode of reproduction and population structure of Leishmania parasites remains opened. It has been suggested that Leishmania parasites could alternate different modes of reproduction, more particularly clonality and frequent recombinations either between related individuals (endogamy) or between unrelated individuals (outcrossing) wi...

  9. Parasitological analysis of synovial fluid from dogs naturally infected with Leishmania sp. / Análise parasitológica do líquido sinovial de cães naturalmente infectados por Leishmania sp

    Scientific Electronic Library Online (English)

    Mayara Nobrega Gomes da, Silva; Deyverson Thiago Prates, Pereira; Maria Ligia de Arruda, Mistieri; Irina, Lubeck.

    2014-07-01

    Full Text Available O objetivo deste estudo foi verificar a viabilidade da análise do líquido sinovial (LS) para o diagnóstico parasitológico de leishmaniose em cães naturalmente infectados. Artrocenteses assépticas das articulações do tarso e do carpo de 40 cães infectados (totalizando 158 amostras articulares) foram [...] realizadas após a eutanásia. Os esfregaços LS foram avaliados sob microscopia óptica e formas amastigotas de Leishmania sp. foram detectadas no LS de 35 cães (87,5%). 93 amostras articulares foram positivas, sendo 53% obtidas a partir das articulações tarsais e 47% obtidas de articulações carpais. Formas amastigotas foram confirmadas em uma (17%), duas (26%), três (31%) ou todas as quatro articulações investigadas (26%). Este trabalho destaca a viabilidade e a alta sensibilidade da avaliação LS para o diagnóstico parasitológico de leishmaniose em cães sintomáticos. Abstract in english The aim of this study was to verify the feasibility of synovial fluid (SF) analysis for the parasitological diagnosis of leishmaniasis in naturally infected dogs. Aseptic arthrocentesis of the tarsal and carpal joints of 40 infected dogs (158 Leishmania sp samples) was conducted after euthanasia. T [...] he SF smears were evaluated under optic microscopy and amastigotes were detected in the SF of 35 dogs (87.5%). Of the 93 positive samples, 53% were obtained from the tarsal joints, and 47% were obtained from the carpal joints. Amastigote forms were confirmed in one (17%), two (26%), three (31%) or all four investigated joints (26%). This research highlights the feasibility and high sensitivity of SF evaluation for the parasitological diagnosis of leishmaniasis in symptomatic dogs.

  10. Cutaneous leishmaniasis in northeastern Brazil: a critical appraisal of studies conducted in State of Pernambuco / Leishmaniose cutânea no nordeste do Brasil: uma avaliação crítica dos estudos realizados no Estado de Pernambuco

    Scientific Electronic Library Online (English)

    Maria Edileuza Felinto de, Brito; Maria Sandra, Andrade; Filipe, Dantas-Torres; Eduardo Henrique Gomes, Rodrigues; Milena de Paiva, Cavalcanti; Alzira Maria Paiva de, Almeida; Sinval Pinto, Brandão-Filho.

    2012-08-01

    Full Text Available A leishmaniose cutânea americana (LCA) é uma doença complexa com características clínicas e epidemiológicas que podem variar de região para região. De fato, pelo menos, sete diferentes espécies de Leishmania, incluindo Leishmania (Viannia) braziliensis, Leishmania (Viannia) guyanensis, Leishmania (V [...] iannia) lainsoni, Leishmania (Viannia) naiffi, Leishmania (Viannia) shawi, Leishmania (Viannia) lindenbergi e Leishmania (Leishmania) amazonensis, têm sido incriminadas na etiologia da LCA no Brasil, e numerosas espécies de flebotomíneos do gênero Lutzomyia, foram considerados vetores suspeitos ou comprovados. Devido ao seu caráter focal, a compreensão da dinâmica da LCA a nível local é imprescindível para a implementação de medidas de controle eficazes. Este trabalho consiste de uma revisão narrativa sobre a epidemiologia da LCA em Pernambuco, nordeste do Brasil. Além disso, se enfatiza a necessidade de maior efetividade no diagnóstico, tratamento, controle e estratégias de prevenção para as populações afetadas. Este artigo fornecerá aos pesquisadores uma avaliação crítica da LCA em Pernambuco. Espera-se também contribuir com as autoridades de saúde pública no aprimoramento das estratégias atuais de controle da LCA nos níveis estaduais e nacional. Abstract in english American cutaneous leishmaniasis (ACL) is a complex disease with clinical and epidemiological features that may vary from region to region. In fact, at least seven different Leishmania species, including Leishmania (Viannia) braziliensis, Leishmania (Viannia) guyanensis, Leishmania (Viannia) lainson [...] i, Leishmania (Viannia) naiffi, Leishmania (Viannia) shawi, Leishmania (Viannia) lindenbergi, and Leishmania (Leishmania) amazonensis, have been implicated in the etiology of ACL in Brazil, and numerous phlebotomine sandfly species of the genus Lutzomyia have been regarded as putative or proven vectors. Because ACL is a focal disease, understanding the disease dynamics at the local level is essential for the implementation of more effective control measures. The present paper is a narrative review about the ACL epidemiology in Pernambuco, northeastern Brazil. Furthermore, the need for more effective diagnosis, treatment, control and prevention strategies for the affected populations is highlighted. This paper will provide researchers with a critical appraisal of ACL in Pernambuco. Hopefully, it will also be helpful for public health authorities to improve current control strategies against ACL at the state and country levels.

  11. Cutaneous leishmaniasis in northeastern Brazil: a critical appraisal of studies conducted in State of Pernambuco Leishmaniose cutânea no nordeste do Brasil: uma avaliação crítica dos estudos realizados no Estado de Pernambuco

    Directory of Open Access Journals (Sweden)

    Maria Edileuza Felinto de Brito

    2012-08-01

    Full Text Available American cutaneous leishmaniasis (ACL is a complex disease with clinical and epidemiological features that may vary from region to region. In fact, at least seven different Leishmania species, including Leishmania (Viannia braziliensis, Leishmania (Viannia guyanensis, Leishmania (Viannia lainsoni, Leishmania (Viannia naiffi, Leishmania (Viannia shawi, Leishmania (Viannia lindenbergi, and Leishmania (Leishmania amazonensis, have been implicated in the etiology of ACL in Brazil, and numerous phlebotomine sandfly species of the genus Lutzomyia have been regarded as putative or proven vectors. Because ACL is a focal disease, understanding the disease dynamics at the local level is essential for the implementation of more effective control measures. The present paper is a narrative review about the ACL epidemiology in Pernambuco, northeastern Brazil. Furthermore, the need for more effective diagnosis, treatment, control and prevention strategies for the affected populations is highlighted. This paper will provide researchers with a critical appraisal of ACL in Pernambuco. Hopefully, it will also be helpful for public health authorities to improve current control strategies against ACL at the state and country levels.A leishmaniose cutânea americana (LCA é uma doença complexa com características clínicas e epidemiológicas que podem variar de região para região. De fato, pelo menos, sete diferentes espécies de Leishmania, incluindo Leishmania (Viannia braziliensis, Leishmania (Viannia guyanensis, Leishmania (Viannia lainsoni, Leishmania (Viannia naiffi, Leishmania (Viannia shawi, Leishmania (Viannia lindenbergi e Leishmania (Leishmania amazonensis, têm sido incriminadas na etiologia da LCA no Brasil, e numerosas espécies de flebotomíneos do gênero Lutzomyia, foram considerados vetores suspeitos ou comprovados. Devido ao seu caráter focal, a compreensão da dinâmica da LCA a nível local é imprescindível para a implementação de medidas de controle eficazes. Este trabalho consiste de uma revisão narrativa sobre a epidemiologia da LCA em Pernambuco, nordeste do Brasil. Além disso, se enfatiza a necessidade de maior efetividade no diagnóstico, tratamento, controle e estratégias de prevenção para as populações afetadas. Este artigo fornecerá aos pesquisadores uma avaliação crítica da LCA em Pernambuco. Espera-se também contribuir com as autoridades de saúde pública no aprimoramento das estratégias atuais de controle da LCA nos níveis estaduais e nacional.

  12. Natural Leishmania sp. reservoirs and phlebotomine sandfly food source identification in Ibitipoca State Park, Minas Gerais, Brazil

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    Patrícia Flávia Quaresma

    2012-06-01

    Full Text Available Leishmania spp are distributed throughout the world and different species are associated with varying degrees of disease severity. However, leishmaniasis is thought to be confined to areas of the world where its insect vectors, sandflies, are present. Phlebotomine sandflies obtain blood meals from a variety of wild and domestic animals and sometimes from humans. These vectors transmit Leishmania spp, the aetiological agent of leishmaniasis. Identification of sandfly blood meals has generally been performed using serological methods, although a few studies have used molecular procedures in artificially fed insects. In this study, cytochrome b gene (cytB polymerase chain reaction (PCR was performed in DNA samples isolated from 38 engorged Psychodopygus lloydi and the expected 359 bp fragment was identified from all of the samples. The amplified product was digested using restriction enzymes and analysed for restriction fragment length polymorphisms (RFLPs. We identified food sources for 23 females; 34.8% yielded a primate-specific banding profile and 26.1% and 39.1% showed banding patterns specific to birds or mixed restriction profiles (rodent/marsupial, human/bird, rodent/marsupial/human, respectively. The food sources of 15 flies could not be identified. Two female P. lloydi were determined to be infected by Leishmania using internal transcribed spacer 1 and heat shock protein 70 kDa PCR-RFLP. The two female sandflies, both of which fed on rodents/marsupials, were further characterised as infected with Leishmania (Viannia braziliensis. These results constitute an important step towards applying methodologies based on cytB amplification as a tool for identifying the food sources of female sandflies.

  13. Natural Leishmania sp. reservoirs and phlebotomine sandfly food source identification in Ibitipoca State Park, Minas Gerais, Brazil

    Scientific Electronic Library Online (English)

    Patrícia Flávia, Quaresma; Gustavo Mayr de Lima, Carvalho; Mariana Campos das Neves Farah, Ramos; José Dilermando, Andrade Filho.

    2012-06-01

    Full Text Available Leishmania spp are distributed throughout the world and different species are associated with varying degrees of disease severity. However, leishmaniasis is thought to be confined to areas of the world where its insect vectors, sandflies, are present. Phlebotomine sandflies obtain blood meals from a [...] variety of wild and domestic animals and sometimes from humans. These vectors transmit Leishmania spp, the aetiological agent of leishmaniasis. Identification of sandfly blood meals has generally been performed using serological methods, although a few studies have used molecular procedures in artificially fed insects. In this study, cytochrome b gene (cytB) polymerase chain reaction (PCR) was performed in DNA samples isolated from 38 engorged Psychodopygus lloydi and the expected 359 bp fragment was identified from all of the samples. The amplified product was digested using restriction enzymes and analysed for restriction fragment length polymorphisms (RFLPs). We identified food sources for 23 females; 34.8% yielded a primate-specific banding profile and 26.1% and 39.1% showed banding patterns specific to birds or mixed restriction profiles (rodent/marsupial, human/bird, rodent/marsupial/human), respectively. The food sources of 15 flies could not be identified. Two female P. lloydi were determined to be infected by Leishmania using internal transcribed spacer 1 and heat shock protein 70 kDa PCR-RFLP. The two female sandflies, both of which fed on rodents/marsupials, were further characterised as infected with Leishmania (Viannia) braziliensis. These results constitute an important step towards applying methodologies based on cytB amplification as a tool for identifying the food sources of female sandflies.

  14. Differences in Lsh gene control over systemic Leishmania major and Leishmania donovani or Leishmania mexicana mexicana infections are caused by differential targeting to infiltrating and resident liver macrophage populations.

    OpenAIRE

    Davies, E.V.; Singleton, A M; Blackwell, J M

    1988-01-01

    Earlier studies had shown that the viscerotropic NIH 173 strain of cutaneous Leishmania major fails to come under Lsh gene control. Visceral Leishmania donovani LV9 and another viscerotropic cutaneous strain, Leishmania mexicana mexicana LV4, are controlled by Lsh. The results of double-infection experiments presented here show that expression of Lsh resistance against L. mexicana mexicana was enhanced in the presence of L. donovani, whereas L. major still failed to come under Lsh gene contro...

  15. Study of Functionalized Gold Nanoparticles with Anti-gp63 IgG Antibody for the Detection of Glycoprotein gp63 in Membrane Surface of Leishmania Genus Parasites

    OpenAIRE

    Alberto Fernández; Manuel Caetano; Vincent Piscitelli; Fracehuli Dager; Yosue Francisco; Jazzmin Arrivillaga; Miguel Medina; Humberto Rojas; Pedro Rodríguez; Jimmy Castillo

    2013-01-01

    In this work we present the preparation and functionalization of gold nanoparticles (AuNPs) for the detection of presence of gp63 glycoprotein in the surface of Leishmania genus parasites. AuNPs were prepared by induced laser ablation in a clean and biologically suitable media. The nanoparticles were functionalized with anti-gp63 lgG antibody in order to study the interaction with the glycoprotein component gp63 (63 kDa) present on the membrane surface of Leishmania genus parasites. The func...

  16. Movement of Heterorhabditis amazonensis and Steinernema arenarium in search of corn fall armyworm larvae in artificial conditions

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    Vanessa Andaló

    2012-06-01

    Full Text Available Spodoptera frugiperda (Smith, 1797 (Lepidoptera: Noctuidae is considered to be the main pest of maize crops in Brazil. Entomopathogenic nematodes (EPN may be used to control this pest and exhibit different, unique abilities to search for their hosts. The movement of EPN in relation to S. frugiperda was evaluated. To test for horizontal movement, a styrofoam enclosure filled with sand was divided into segments, nematodes were placed at the entrance to the enclosure and a larva was placed at the end of each division. The same approach was used to evaluate vertical movement; however, PVC pipes were used in this case. In general, the mortality was inversely proportional to the initial distance between host and nematodes. In the vertical displacement test, both nematodes were able to kill the larvae up to a distance of 25 cm. Therefore, the infective juveniles of H. amazonensis and S. arenarium can search out, infect and kill larvae of S. frugiperda at distances of up to 60 cm and 25 cm of horizontal and vertical displacement, respectively.

  17. Partial purification, immunogenicity and putative new localization of a native Leishmania heat shock protein 70

    Scientific Electronic Library Online (English)

    ELIETE CAVALCANTI, DA SILVA; CYNTHIA D, RAYOL; PATRICIA M. M. F, MOURA; PAULO P, ANDRADE.

    2008-12-01

    Full Text Available Neste trabalho estudamos urna proteína recombinante (S7) contendo aproximadamente 230 aminoácidos da extremidade carboxi-terminal da proteína de choque térmico de 70 kDa (HSP70) de Leishmania chagasi. As proteínas de choque térmico estâo entre os antígenos parasitarios mais abundantes e mais conserv [...] ados na natureza. Esta familia pertence a urna das classes de proteínas mais imunogênicas, presentes em organismos patogênicos. Aproteína S7 foi parcialmente purificada por eletroeluição, e em seguida precipitada em acetona. A eletroeluição não modificou suas propriedades imunológicas e antigênicas, pois a proteína continuou a ser reconhecida (tanto no ELISA como no Western blot) por soros positivos para leishmaniose visceral e pelo sistema imunológico de coelhos durante a imunização. Aproducção de soros policlonais com urna concentração antigênica muito inferior a dose máxima, reforca a idéia de que as proteínas desta familia sâo altamente antigênicas e imunogénicas. Nossos resultados com os soros policlonais no ensaio de aglutinação direta (DAT) permitem concluir que a HSP70 nativa de L. chagasi está presente na superficie do parásita. Abstract in english In this work we focused on a recombinant protein, containing approximately 230 aminoacids from the carboxy-terminal extremity of the Leishmania chagasi heat shock protein 70. The heat shock proteins are among the most abundant parasite antigens and conserved proteins in nature, and this family is on [...] e of the most immunogenic proteins present within pathogenic organisms. The recombinant protein has been partially purified by electroelution and further precipitation in acetone. The electroelution process did not modify its immunological and antigenic properties, as it continued to be recognized by visceral leishmaniasis positive sera and by the immunological system of rabbits during the immunization, both in ELISA and Western blots. The production of polyclonal sera with an antigen concentration that is far from the maximum dose, strengthens the idea that the proteins of this family are highly antigenic and immunogenic. Our results with these polyclonal sera in the Direct Agglutination Assay allow the conclusion that the Leishmania chagasi native heat shock protein 70 is distributed on the surface of the parasite.

  18. In Vitro and In Vivo Antileishmanial Effects of Pistacia khinjuk against Leishmania tropica and Leishmania major.

    Science.gov (United States)

    Ezatpour, Behrouz; Saedi Dezaki, Ebrahim; Mahmoudvand, Hossein; Azadpour, Mojgan; Ezzatkhah, Fatemeh

    2015-01-01

    The present study aims to evaluate the in vitro and in vivo antileishmanial activities of Pistacia khinjuk Stocks (Anacardiaceae) alcoholic extract and to compare its efficacy with a reference drug, meglumine antimoniate (MA, Glucantime), against Leishmania tropica and Leishmania major. This extract (0-100?µg/mL) was evaluated in vitro against promastigote and intracellular amastigote forms of L. tropica (MRHO/IR/75/ER) and then tested on cutaneous leishmaniasis (CL) in male BALB/c mice with L. major to reproduce the antileishmanial activity topically. In vitro, P. khinjuk extract significantly (P < 0.05) inhibited the growth rate of promastigote (IC50?58.6 ± 3.2?µg/mL) and intramacrophage amastigotes (37.3 ± 2.5?µg/mL) of L. tropica as a dose-dependent response. In the in vivo assay, after 30 days of treatment, 75% recovery was observed in the infected mice treated with 30% extract. After treatment of the subgroups with the concentration of 20 and 30% of P. khinjuk extract, mean diameter of lesions was significantly (P < 0.05) reduced. To conclude, the present investigation demonstrated that P. vera extract had in vitro and in vivo effectiveness against L. major. Obtained findings also provide the scientific evidences that natural plants could be used in the traditional medicine for the prevention and treatment of CL. PMID:25815025

  19. Seasonal transmission of Leishmania (Leishmania mexicana in the state of Campeche, Yucatan Peninsula, Mexico

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    Andrade-Narvaez Fernando J

    2003-01-01

    Full Text Available In the Yucatan Peninsula, Mexico, localized cutaneous leishmaniasis (LCL caused by Leishmania (Leishmania mexicana is a typical wild zoonosis restricted to the forest, and humans are only accidentally involved. The transmission of L. (L. mexicana has been related to the patient's occupation: "chicleros"(gum collectors and agricultural workers. The objective of this study was to document L. (L. mexicana seasonally of transmission in endemic areas of LCL in the state of Campeche, Yucatan Peninsula, Mexico. The timing of incidence of LCL in humans during 1993-1994, as well as the rate and time of infection in rodents and sand flies between February 1993 and March 1995 were analyzed. Rodents and sand flies were found infected between November and March, when men carried out their field activities and are exposed. Based on results analyzed, it is concluded that L. (L. mexicana in the endemic area of LCL in the state of Campeche, Yucatan Peninsula, Mexico, presents a seasonal transmission restricted to the months of November to March. The knowledge of the timing of the transmission cycle in an endemic area of leishmaniasis is very important because intervention measures on the high-risk focus and population might be restricted.

  20. Seasonal transmission of Leishmania (Leishmania) mexicana in the state of Campeche, Yucatan Peninsula, Mexico

    Scientific Electronic Library Online (English)

    Fernando J, Andrade-Narvaez; Silvia B Canto, Lara; Nicole R, Van Wynsberghe; Eduardo A, Rebollar-Tellez; Alberto, Vargas-Gonzalez; Nelly E, Albertos-Alpuche.

    2003-12-01

    Full Text Available In the Yucatan Peninsula, Mexico, localized cutaneous leishmaniasis (LCL) caused by Leishmania (Leishmania) mexicana is a typical wild zoonosis restricted to the forest, and humans are only accidentally involved. The transmission of L. (L.) mexicana has been related to the patient's occupation: "chi [...] cleros"(gum collectors) and agricultural workers. The objective of this study was to document L. (L.) mexicana seasonally of transmission in endemic areas of LCL in the state of Campeche, Yucatan Peninsula, Mexico. The timing of incidence of LCL in humans during 1993-1994, as well as the rate and time of infection in rodents and sand flies between February 1993 and March 1995 were analyzed. Rodents and sand flies were found infected between November and March, when men carried out their field activities and are exposed. Based on results analyzed, it is concluded that L. (L.) mexicana in the endemic area of LCL in the state of Campeche, Yucatan Peninsula, Mexico, presents a seasonal transmission restricted to the months of November to March. The knowledge of the timing of the transmission cycle in an endemic area of leishmaniasis is very important because intervention measures on the high-risk focus and population might be restricted.

  1. Chronic interstitial pneumonitis in dogs naturally infected with Leishmania (Leishmania chagasi: a histopathological and morphometric study

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    Gonçalves Ricardo

    2003-01-01

    Full Text Available Eighteen mongrel dogs of unknown age and naturally infected with Leishmania (Leishmania chagasi, were obtained from the City Hall of Belo Horizonte, Brazil. Four dogs were used as control. Lung samples were obtained and immediately fixed in formalin. The histopathological picture of all lung tissue sections was a chronic and diffuse interstitial pneumonitis. The thickened inter-alveolar septa were characterized by the cellular exudate (mostly macrophages, lymphocytes and plasmocytes associated with collagen deposition. Morphometric analysis showed greater septal thickness in the infected animals than in controls. In fact, the morphometric study of collagen stained with ammoniac silver confirmed a larger deposition of collagen in the infected animals. The parasitologic method was carried out during the study of the lesions on the slides. However, we did not observe any correlation between the histopathologic and morphometric data and the clinical status of the animals. We conclude that the pulmonary lesions observed in all naturally infected dogs were correlated with the disease and that the morphometric method used was satisfactory for the analysis of septal thickness and of increased collagen deposition, confirming the presence of fibrosis.

  2. Identification of Leishmania (Leishmania) chagasi isolated from healthy skin of symptomatic and asymptomatic dogs seropositive for leishmaniasis in the Municipality of Rio de Janeiro, Brazil

    OpenAIRE

    Maria de Fátima Madeira; Armando de Oliveira Schubach; Tânia Maria Pacheco Schubach; Cristianni Antunes Leal; Mauro Célio de Almeida Marzochi

    2004-01-01

    Euthanasia of seropositive dogs has been one of the principal measures adopted by the Program for the Control of Leishmaniasis in Brazil for many years. However, its efficacy is currently being questioned. We obtained intact skin samples from 20 Leishmania-reactive dogs from the municipality of Rio de Janeiro that had been referred for euthanasia. The promastigote forms of Leishmania were isolated in culture from 18 of these animals. Fourteen of these isolates were identified as Leishmania (L...

  3. Immunosuppressive Activity of Leishmania major Culture Supernatant

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    M Abolhassani

    2006-07-01

    Full Text Available BALB/c mice are highly susceptible to infection with the protozoan parasite Leishmania major. This susceptibility has been attributed in part to the expansion of Th2 cells and production of their cytokines, IL-4 and IL-10 and down-regulation of Th1 cytokine, INF-?. The inability of susceptible hosts to mount the immune response necessary to activate macrophage and destroy the parasites can be due to the parasite-specific proteins that are able to modulate the immune system. In this report, we monitored the culture supernatant of the parasite in order to show the existence of immunosuppressive factor. The L. major parasites were isolated from lesion of infected BALB/c mice. Amastigotes were grown at 35 °C and promastigotes at 22-25°C in the presence of 10% FCS. Culture supernatants were harvested after 72 h of incubation and used for lymphocyte proliferation assay using lymph node and spleen cells stimulated with mitogens. We have shown that the excretory materials of promastigotes and axenic amastigotes have a potent immunosuppressive activity. Culture supernatants can suppress the proliferation of mitogen-stimulated lymph node lymphocytes (74% or spleen cells (90% in a dose-dependent manner. This result may show that parasite by excretory materials can influence INF-? production by T cells and macrophage activation in order to survive within the macrophage and propagating inside the phagolysosome.

  4. Leishmania (L.) mexicana Infected Bats in Mexico: Novel Potential Reservoirs

    Science.gov (United States)

    Berzunza-Cruz, Miriam; Rodríguez-Moreno, Ángel; Gutiérrez-Granados, Gabriel; González-Salazar, Constantino; Stephens, Christopher R.; Hidalgo-Mihart, Mircea; Marina, Carlos F.; Rebollar-Téllez, Eduardo A.; Bailón-Martínez, Dulce; Balcells, Cristina Domingo; Ibarra-Cerdeña, Carlos N.; Sánchez-Cordero, Víctor; Becker, Ingeborg

    2015-01-01

    Leishmania (Leishmania) mexicana causes cutaneous leishmaniasis, an endemic zoonosis affecting a growing number of patients in the southeastern states of Mexico. Some foci are found in shade-grown cocoa and coffee plantations, or near perennial forests that provide rich breeding grounds for the sand fly vectors, but also harbor a variety of bat species that live off the abundant fruits provided by these shade-giving trees. The close proximity between sand flies and bats makes their interaction feasible, yet bats infected with Leishmania (L.) mexicana have not been reported. Here we analyzed 420 bats from six states of Mexico that had reported patients with leishmaniasis. Tissues of bats, including skin, heart, liver and/or spleen were screened by PCR for Leishmania (L.) mexicana DNA. We found that 41 bats (9.77%), belonging to 13 species, showed positive PCR results in various tissues. The infected tissues showed no evidence of macroscopic lesions. Of the infected bats, 12 species were frugivorous, insectivorous or nectarivorous, and only one species was sanguivorous (Desmodus rotundus), and most of them belonged to the family Phyllostomidae. The eco-region where most of the infected bats were caught is the Gulf Coastal Plain of Chiapas and Tabasco. Through experimental infections of two Tadarida brasiliensis bats in captivity, we show that this species can harbor viable, infective Leishmania (L.) mexicana parasites that are capable of infecting BALB/c mice. We conclude that various species of bats belonging to the family Phyllostomidae are possible reservoir hosts for Leishmania (L.) mexicana, if it can be shown that such bats are infective for the sand fly vector. Further studies are needed to determine how these bats become infected, how long the parasite remains viable inside these potential hosts and whether they are infective to sand flies to fully evaluate their impact on disease epidemiology. PMID:25629729

  5. Presence of amastigotes in the central nervous system of hamsters infected with Leishmania sp. Presença de amastigotas em sistema nervoso central de hamster infectado com Leishmania sp.

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    Elisangela de Oliveira

    2011-06-01

    Full Text Available Visceral leishmaniasis (VL is a severe chronic disease caused by Leishmania (Leishmania infantum chagasi. Better knowledge on the effects caused by this disease can help develop adequate clinical management and treatment. Parasitological and immunohistochemical studies were performed golden hamsters Mesocricetus auratus infected with bone marrow from individuals with VL in the State of Mato Grosso do Sul, central-west Brazil. The effects of parasitism in the spleen, liver, kidneys, lungs, heart and brain of the animals were examined. Eighteen hamsters were inoculated intraperitoneally, and six healthy animals were used as negative controls. The animals were kept in the animal house and checked for clinical signs. Specimens of each organ were examined for the presence of amastigotes. Immunohistochemical technique was performed in all brain specimens and organs negative on the direct examination of parasites. Direct examination of amastigotes was positive in the spleen and liver of all infected animals; 33.3% showed the parasite in the kidneys and lungs, and 16.7% in the heart. Parasitic forms were seen in 83.3% (15/18 of the brain examined. Immunohistochemistry confirmed the results of the direct examination, except in two specimens of lung tissue and in the brain specimens. Other studies are needed to further clarify the effect of the parasite in the central nervous system.A leishmaniose visceral (LV é uma doença crônica grave, causada pelo parasito Leishmania (Leishmania infantum chagasi. Esclarecer as alterações provocadas pela doença é fundamental para que se adotem condutas clínicas e de tratamento adequadas. Com o objetivo de analisar a infecção experimental em hamsters da linhagem golden, Mesocricetus auratus, infectados com tecido de medula óssea de pacientes com LV no Estado de Mato Grosso do Sul, foram realizados estudos parasitológicos e de imunomarcação. Foi verificada a distribuição do parasitismo no baço, fígado, rim, pulmão, coração e encéfalo desses animais. Foram utilizados 18 hamsters experimentalmente inoculados via intra-peritoneal, e seis animais sadios como controles negativos. Os animais foram mantidos em biotério de experimentação e observados, em busca de alterações clínicas. Com fragmentos de cada órgão, procedeu-se a confecção de lâminas por aposição para pesquisa de amastigotas. Nos órgãos com resultado negativo na pesquisa direta do parasito, e em todas as amostras de encéfalo, foi realizada a técnica de imunohistoquímica. A pesquisa direta de amastigotas foi positiva no baço e fígado de todos os animais infectados; 33,3% apresentaram o parasito em rim e pulmão, e 16,7% no coração. Quando realizada a pesquisa em encéfalo, formas parasitárias foram observadas em 83,3% (15/18 dos animais. A imunomarcação confirmou os resultados da pesquisa direta, exceto em duas amostras de tecido pulmonar e nas amostras de encéfalo. Mais estudos são necessários, para esclarecer o real papel do parasito no sistema nervoso central.

  6. Presence of amastigotes in the central nervous system of hamsters infected with Leishmania sp. / Presença de amastigotas em sistema nervoso central de hamster infectado com Leishmania sp.

    Scientific Electronic Library Online (English)

    Elisangela de, Oliveira; Elisa Teruya, Oshiro; Rebeca Vieira, Pinto; Bruna Corrêa de, Castro; Karla Borges, Daniel; Janaina Michelle de, Oliveira; Manoel Sebastião da Costa, Lima Júnior; Euripedes Batista, Guimarães; Jesiel Mamedes, Silva; Maria Elizabeth Cavalheiros, Dorval.

    2011-06-01

    Full Text Available A leishmaniose visceral (LV) é uma doença crônica grave, causada pelo parasito Leishmania (Leishmania) infantum chagasi. Esclarecer as alterações provocadas pela doença é fundamental para que se adotem condutas clínicas e de tratamento adequadas. Com o objetivo de analisar a infecção experimental em [...] hamsters da linhagem golden, Mesocricetus auratus, infectados com tecido de medula óssea de pacientes com LV no Estado de Mato Grosso do Sul, foram realizados estudos parasitológicos e de imunomarcação. Foi verificada a distribuição do parasitismo no baço, fígado, rim, pulmão, coração e encéfalo desses animais. Foram utilizados 18 hamsters experimentalmente inoculados via intra-peritoneal, e seis animais sadios como controles negativos. Os animais foram mantidos em biotério de experimentação e observados, em busca de alterações clínicas. Com fragmentos de cada órgão, procedeu-se a confecção de lâminas por aposição para pesquisa de amastigotas. Nos órgãos com resultado negativo na pesquisa direta do parasito, e em todas as amostras de encéfalo, foi realizada a técnica de imunohistoquímica. A pesquisa direta de amastigotas foi positiva no baço e fígado de todos os animais infectados; 33,3% apresentaram o parasito em rim e pulmão, e 16,7% no coração. Quando realizada a pesquisa em encéfalo, formas parasitárias foram observadas em 83,3% (15/18) dos animais. A imunomarcação confirmou os resultados da pesquisa direta, exceto em duas amostras de tecido pulmonar e nas amostras de encéfalo. Mais estudos são necessários, para esclarecer o real papel do parasito no sistema nervoso central. Abstract in english Visceral leishmaniasis (VL) is a severe chronic disease caused by Leishmania (Leishmania) infantum chagasi. Better knowledge on the effects caused by this disease can help develop adequate clinical management and treatment. Parasitological and immunohistochemical studies were performed golden hamste [...] rs Mesocricetus auratus infected with bone marrow from individuals with VL in the State of Mato Grosso do Sul, central-west Brazil. The effects of parasitism in the spleen, liver, kidneys, lungs, heart and brain of the animals were examined. Eighteen hamsters were inoculated intraperitoneally, and six healthy animals were used as negative controls. The animals were kept in the animal house and checked for clinical signs. Specimens of each organ were examined for the presence of amastigotes. Immunohistochemical technique was performed in all brain specimens and organs negative on the direct examination of parasites. Direct examination of amastigotes was positive in the spleen and liver of all infected animals; 33.3% showed the parasite in the kidneys and lungs, and 16.7% in the heart. Parasitic forms were seen in 83.3% (15/18) of the brain examined. Immunohistochemistry confirmed the results of the direct examination, except in two specimens of lung tissue and in the brain specimens. Other studies are needed to further clarify the effect of the parasite in the central nervous system.

  7. Riesgo de transmisión de Leishmania (Kinetoplastida: Trypanosomatidae en Mérida Venezuela

    Directory of Open Access Journals (Sweden)

    Elsa Nieves

    2014-09-01

    Full Text Available La leishmaniasis es una enfermedad causada por la infección de un parásito protozoario del género Leishmania, transmitido por la picada de insectos hematófagos conocidos como flebotominos. El estudio tiene como objetivo determinar la presencia de flebotominos en los Distritos Sanitarios del estado Mérida y diseñar un mapa de riesgo de transmisión entomológico. Se utilizaron cuatro métodos de captura de flebotominos, los ejemplares se identificaron y se les determinó la infección natural por Leishmania. Se estimó la riqueza de especies, y se realizó un proceso analítico Jerárquico. Los resultados muestran la presencia de diversas especies de flebotominos en los Distritos Sanitarios del estado Mérida, siendo las especies de mayor frecuencia L. youngi, L. gomezi, L. ovallesi y L. walkeri. Se detectó 2,1% de infección natural con Leishmania, la cual se encontró en las 4 especies más frecuentes. Se presenta un mapa de riesgo de transmisión entomológico para el estado Mérida. El conocimiento de la situación actual de los vectores de Leishmania en el estado Mérida y el riesgo de transmisión son relevantes a la hora de considerar la prevención y posible surgimiento de nuevos brotes de leishmaniasis. Abstract (english The leishmaniasis is a disease caused by infection with a protozoan parasite of the genus Leishmania, transmitted by the bite of blood-sucking insects known as sandflies. The study aims to determine the presence of sandflies in Merida state health districts and design a map of entomological risk of transmission. Four methods capture sandflies were used, the specimens were identified and natural Leishmania infection was determined. The richness species was estimated and analityc Hierarchie procesess was performed. The results show the presence of various species of sandflies in Merida state health districts, L. youngi, L. gomezi, L. ovallesi and L. walkeri were most abundant species. The 2.1% of natural infection with Leishmania was detected, which were found in the 4 most abundant species. A map of risk of transmission to Mérida is presented. Knowledge of the current status of Leishmania vectors in Mérida and the risk of transmission are relevant when considering the prevention and possible emergence of new outbreaks of leishmaniasis.

  8. Histological changes and immunolabeling of Leishmania infantum in kidneys and urinary bladder of dogs / Alterações histológicas e imunomarcação de Leishmania infantum em rins e bexiga de cães

    Scientific Electronic Library Online (English)

    Jamile Prado dos, Santos; Leucio Camara, Alves; Rafael Antonio Nascimento, Ramos; Danillo de Souza, Pimentel; Gilcia Aparecida de, Carvalho; Maria Fernanda Melo, Monteiro; Maria Aparecida da Gloria, Faustino.

    2013-09-01

    Full Text Available Objetivou-se neste estudo avaliar as alterações histológicas e realizar a imunomarcação de Leishmania infantum em rins e bexiga de cães naturalmente infectados. Vinte e cinco amostras de bexiga e rins de animais sorologicamente (ELISA S7® Biogene and IFAT ? 1:40 - Biomanguinhos/Fiocruz) positivas fo [...] ram analisadas histologicamente e por meio da técnica de imuno-histoquímica. Os resultados revelaram cistite em 44% (11/25) das amostras de bexiga e glomerulonefrite membranoproliferativa em 92% (23/25) das amostras de rins. A imunomarcação do parasito revelou 32% (8/25) e 8% (2/25) de positividade em bexiga e rins, respectivamente. Conclui-se que a técnica de imunohistoquímica é uma útil ferramenta para detecção de formas amastigotas de L. infantum em órgãos de cães infectados. Além disso, o presente trabalho reporta a primeira descrição de formas amastigotas de L. infantum em bexiga de cães. Abstract in english The aim of this study was to assess histological alterations and perform immunolabeling of Leishmania infantum in the kidneys and urinary bladder of naturally infected dogs. Twenty-five urinary bladder and kidney samples of serologically positive animals (ELISA S7® Biogene and IFAT ? 1:40 - Biomangu [...] inhos/Fiocruz) were analyzed by means of immunohistochemical and histological techniques. Cystitis was found in 44% (11/25) of the bladder samples and membranoproliferative glomerulonephritis in 92% (23/25) of the kidney samples. Immunolabeling of the parasite revealed that 32% (8/25) of the bladders and 8% (2/25) of the kidneys were positive. In conclusion, the immunohistochemical technique is a useful tool for detecting amastigote forms of L. infantum in organs of infected dogs. In addition, this was the first report of detection of amastigote forms of L. infantum in the bladders of dogs.

  9. Identification of a differentially expressed mRNA in axenic Leishmania panamensis amastigotes

    Directory of Open Access Journals (Sweden)

    José Arturo Gutiérrez

    2001-08-01

    Full Text Available Differential display technique was applied in order to identify transcripts which are present in axenic amastigotes but not in promastigotes of the Leishmania panamensis parasites. One of them was cloned and the sequence reveals an open reading frame of 364 amino acids (aprox. 40 kDa. The deduced protein is homologous to the serine/threonine protein kinases and specially to the mitogen activates protein kinases from eukaryotic species. Southern blot analysis suggest that this transcript, named lpmkh, is present in the genome of the parasite as a single copy gene. These results could imply that lpmkh could be involved in the differentiation process or the preservation of amastigotes in axenic conditions.

  10. Characterization of anti-silencing factor 1 in Leishmania major

    Directory of Open Access Journals (Sweden)

    Ricardo Scher

    2012-05-01

    Full Text Available Anti-silencing factor 1 (ASF1 is a histone chaperone that contributes to the histone deposition during nucleosome assembly in newly replicated DNA. It is involved in chromatin disassembly, transcription activation and in the cellular response to DNA damage. In Leishmania major the ASF1 gene (LmASF1 is located in chromosome 20 and codes for a protein showing 67% of identity with the Trypanosoma brucei TbASF1a. Compared to orthologous proteins, LmASF1 conserves the main residues relevant for its various biological functions. To study ASF1 in Leishmania we generated a mutant overexpressing LmASF1 in L. major. We observed that the excess of LmASF1 impaired promastigotes growth rates and had no impact on cell cycle progress. Differently from yeast, ASF1 overproduction in Leishmania did not affect expression levels of genes located on telomeres, but led to an upregulation of proteins involved in chromatin remodelling and physiological stress, such as heat shock proteins, oxidoreductase activity and proteolysis. In addition, we observed that LmASF1 mutant is more susceptible to the DNA damaging agent, methyl methane sulphonate, than the control line. Therefore, our study suggests that ASF1 from Leishmania pertains to the chromatin remodelling machinery of the parasite and acts on its response to DNA damage.

  11. Sand fly evolution and its relationship to Leishmania transmission

    Directory of Open Access Journals (Sweden)

    PD Ready

    2000-08-01

    Full Text Available The evolutionary relationships of sand flies and Leishmania are discussed in this report, which draws distinctions between co-association, co-evolution and co-speciation (or co-cladogenesis. Examples focus on Phlebotomus vectors of Le. infantum and Le. major in the Mediterranean subregion.

  12. Zosteriform cutaneous leishmaniasis due to Leishmania ( Viannia ) panamensis and Leishmania ( Viannia ) braziliensis: Report of three cases / Leishmaniasis cutánea zosteriforme causada por Leishmania ( Viannia) panamensis y Leishmania ( Viannia ) braziliensis: reporte de tres casos

    Scientific Electronic Library Online (English)

    Camilo Andrés, Morales; Juliana, Palacio; Gerzaín, Rodríguez; Yenny Carolina, Camargo.

    2014-09-01

    Full Text Available La leishmaniasis zosteriforme es una variante clínica de la leishmaniasis cutánea, infrecuente y poco conocida en Colombia. Clínicamente se caracteriza por una o varias placas conformadas por pápulas y pseudovesículas que siguen un patrón lineal, y por lesiones satelitales que comprometen uno o vari [...] os dermatomas sin sobrepasar la línea media. Se presentan tres casos de leishmaniasis cutánea zosteriforme en los que se identificaron Leishmania panamensis y Leishmania braziliensis como especies infectantes. La sospecha epidemiológica derivada de la procedencia de los pacientes, así como la sospecha clínica a partir del reconocimiento de una presentación infrecuente de la enfermedad, permitieron hacer el diagnóstico. Abstract in english In Colombia, zosteriform leishmaniasis is a little-known and infrequent clinical variant of cutaneous leishmaniasis. Its clinical features include one or more plaques made up of papules and pseudo-vesicles, which conform to a lineal pattern, as well as satellite lesions that affect one or more derma [...] tomes, without crossing the median line. We present three zosteriform cutaneous leishmaniasis cases in which Leishmania panamensis and Leishmania braziliensis were identified as the infective species. In light of the fact that the disease occurs infrequently, diagnosis was reached by taking into account epidemiological and clinical suspicion.

  13. Molecular detection of Leishmania infantum in naturally infected

    Directory of Open Access Journals (Sweden)

    C. Maia, M.O. Afonso, L. Neto, L. Dionísio & L. Campino

    2009-12-01

    Full Text Available Background & objectives: In Portugal, Phlebotomus perniciosus and P. ariasi, (SubgenusLarroussius; Diptera: Psychodidae are the proven vectors of leishmaniasis caused by Leishmaniainfantum. The Algarve Region in southern Portugal has been considered an endemic focus ofleishmaniasis since 1980s. The main objective of the present study was to validate a molecularapproach to detect Leishmania infection in phlebotomines based on DNA extraction from thefemale sandfly whole body, minus genitalia, followed by PCR for application on epidemiologicalsurveys.Methods: In Algarve Region, from early May until early November 2006, sandflies were capturedby CDC miniature light-traps. kDNA-PCR and ITS1-PCR were used to screen the presence ofLeishmania DNA in female sandflies after species identification by entomological keys.Results: A total of 474 sandflies were collected in 108 biotopes. One female of P. perniciosus, thepredominant species, was found infected with L. infantum reflecting an overall infection rate of0.47%.Interpretation & conclusion: PCR associated with morphological characterization of the sandflieswill be a powerful epidemiological tool for the determination of the number of phlebotominesinfected with Leishmania spp in nature. In addition, the simultaneous occurrence of dogs and P.perniciosus infected with L. infantum shows that Algarve continues to be an endemic focus ofcanine leishmaniasis. Furthermore, as P. sergenti and P. papatasi which transmit L. tropica and L.major, respectively were present, the future introduction of these two Leishmania species in southernregion of Portugal should not be neglected.

  14. Leishmania parasite detection and quantification using PCR-ELISA.

    Czech Academy of Sciences Publication Activity Database

    Kobets, Tetyana; Badalová, Jana; Grekov, Igor; Havelková, Helena; Lipoldová, Marie

    2010-01-01

    Ro?. 5, ?. 6 (2010), s. 1074-1080. ISSN 1754-2189 R&D Projects: GA ?R GA310/08/1697; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z50520514 Keywords : polymerase chain reaction * Leishmania major infection * parasite quantification Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 8.362, year: 2010

  15. Manifestations of paediatric Leishmania infantum infections in Malta

    OpenAIRE

    Pace, D.; Williams, Tn; Grochowska, A.; Betts, A.; Attard-montalto, S.; Boffa, Mj; Vella, C.

    2011-01-01

    Leishmania infantum is endemic in the Maltese archipelago, a group of islands in the Mediterranean which are visited frequently by tourists from Northern European countries. The burden of leishmaniasis is highest in children who may present with cutaneous or visceral manifestations. We describe systematically the manifestations, diagnosis and management of leishmaniasis in children

  16. Molecular Modeling of Cathepsin B protein in different Leishmania strains

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    Pawan Kumar Jayaswal

    2011-02-01

    Full Text Available Cathepsin B like cysteine proteases representing a major component of the lysosomal proteolytic repertoire plays an important role in intracel-lular protein degradation. Comparative models of cathepsin B (CatB protein of six different Leishmania strains were developed using MOD-ELLER. The modeled three-dimensional (3-D structure has the correct stereochemistry as gauged from the Ramachandran plot and good 3-D structure compatibility as assessed by PROCHECK and the DOPE score (DS2.1, Accelrys. The modeled proteins were energy minimized and validated using standard dynamic cascade protocol (DS 2.1. Seven different disulfide bonding sites are predicted in CatB protein of Leishma-nia. Two domains were identified and different motifs are present in catB protein of Leishmania like aspargine glycosylation sites, protein ki-nase phosphorylation sites, protein kinase C activation sites and N-myristoylation sites. Considering that cathepsin B is essential for survival of Leishmania, including for virulence to the mammalian host, it may be viewed as an attractive drug target.

  17. Wild and synanthropic reservoirs of Leishmania species in the Americas.

    Science.gov (United States)

    Roque, André Luiz R; Jansen, Ana Maria

    2014-12-01

    The definition of a reservoir has changed significantly in the last century, making it necessary to study zoonosis from a broader perspective. One important example is that of Leishmania, zoonotic multi-host parasites maintained by several mammal species in nature. The magnitude of the health problem represented by leishmaniasis combined with the complexity of its epidemiology make it necessary to clarify all of the links in transmission net, including non-human mammalian hosts, to develop effective control strategies. Although some studies have described dozens of species infected with these parasites, only a minority have related their findings to the ecological scenario to indicate a possible role of that host in parasite maintenance and transmission. Currently, it is accepted that a reservoir may be one or a complex of species responsible for maintaining the parasite in nature. A reservoir system should be considered unique on a given spatiotemporal scale. In fact, the transmission of Leishmania species in the wild still represents an complex enzootic "puzzle", as several links have not been identified. This review presents the mammalian species known to be infected with Leishmania spp. in the Americas, highlighting those that are able to maintain and act as a source of the parasite in nature (and are thus considered potential reservoirs). These host/reservoirs are presented separately in each of seven mammal orders - Marsupialia, Cingulata, Pilosa, Rodentia, Primata, Carnivora, and Chiroptera - responsible for maintaining Leishmania species in the wild. PMID:25426421

  18. Leishmania development in sand flies: parasite-vector interactions overview

    Directory of Open Access Journals (Sweden)

    Dostálová Anna

    2012-12-01

    Full Text Available Abstract Leishmaniases are vector-borne parasitic diseases with 0.9 – 1.4 million new human cases each year worldwide. In the vectorial part of the life-cycle, Leishmania development is confined to the digestive tract. During the first few days after blood feeding, natural barriers to Leishmania development include secreted proteolytic enzymes, the peritrophic matrix surrounding the ingested blood meal and sand fly immune reactions. As the blood digestion proceeds, parasites need to bind to the midgut epithelium to avoid being excreted with the blood remnant. This binding is strictly stage-dependent as it is a property of nectomonad and leptomonad forms only. While the attachment in specific vectors (P. papatasi, P. duboscqi and P. sergenti involves lipophosphoglycan (LPG, this Leishmania molecule is not required for parasite attachment in other sand fly species experimentally permissive for various Leishmania. During late-stage infections, large numbers of parasites accumulate in the anterior midgut and produce filamentous proteophosphoglycan creating a gel-like plug physically obstructing the gut. The parasites attached to the stomodeal valve cause damage to the chitin lining and epithelial cells of the valve, interfering with its function and facilitating reflux of parasites from the midgut. Transformation to metacyclic stages highly infective for the vertebrate host is the other prerequisite for effective transmission. Here, we review the current state of knowledge of molecular interactions occurring in all these distinct phases of parasite colonization of the sand fly gut, highlighting recent discoveries in the field.

  19. Tetracycline-inducible gene expression system in Leishmania mexicana.

    Czech Academy of Sciences Publication Activity Database

    Kraeva, N.; Ishemgulova, A.; Lukeš, Julius; Yurchenko, Vyacheslav

    2014-01-01

    Ro?. 198, ?. 1 (2014), s. 11-13. ISSN 0166-6851 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Leishmania mexicana * Gene expression * Tet-inducible system Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.243, year: 2013

  20. Wild and synanthropic reservoirs of Leishmania species in the Americas

    Directory of Open Access Journals (Sweden)

    André Luiz R. Roque

    2014-12-01

    Full Text Available The definition of a reservoir has changed significantly in the last century, making it necessary to study zoonosis from a broader perspective. One important example is that of Leishmania, zoonotic multi-host parasites maintained by several mammal species in nature. The magnitude of the health problem represented by leishmaniasis combined with the complexity of its epidemiology make it necessary to clarify all of the links in transmission net, including non-human mammalian hosts, to develop effective control strategies. Although some studies have described dozens of species infected with these parasites, only a minority have related their findings to the ecological scenario to indicate a possible role of that host in parasite maintenance and transmission. Currently, it is accepted that a reservoir may be one or a complex of species responsible for maintaining the parasite in nature. A reservoir system should be considered unique on a given spatiotemporal scale. In fact, the transmission of Leishmania species in the wild still represents an complex enzootic “puzzle”, as several links have not been identified. This review presents the mammalian species known to be infected with Leishmania spp. in the Americas, highlighting those that are able to maintain and act as a source of the parasite in nature (and are thus considered potential reservoirs. These host/reservoirs are presented separately in each of seven mammal orders – Marsupialia, Cingulata, Pilosa, Rodentia, Primata, Carnivora, and Chiroptera – responsible for maintaining Leishmania species in the wild.

  1. Characterization of anti-silencing factor 1 in Leishmania major

    Scientific Electronic Library Online (English)

    Ricardo, Scher; Juliana Bório Ferreira, Garcia; Bruno, Pascoalino; Sergio, Schenkman; Angela Kaysel, Cruz.

    2012-05-01

    Full Text Available Anti-silencing factor 1 (ASF1) is a histone chaperone that contributes to the histone deposition during nucleosome assembly in newly replicated DNA. It is involved in chromatin disassembly, transcription activation and in the cellular response to DNA damage. In Leishmania major the ASF1 gene (LmASF1 [...] ) is located in chromosome 20 and codes for a protein showing 67% of identity with the Trypanosoma brucei TbASF1a. Compared to orthologous proteins, LmASF1 conserves the main residues relevant for its various biological functions. To study ASF1 in Leishmania we generated a mutant overexpressing LmASF1 in L. major. We observed that the excess of LmASF1 impaired promastigotes growth rates and had no impact on cell cycle progress. Differently from yeast, ASF1 overproduction in Leishmania did not affect expression levels of genes located on telomeres, but led to an upregulation of proteins involved in chromatin remodelling and physiological stress, such as heat shock proteins, oxidoreductase activity and proteolysis. In addition, we observed that LmASF1 mutant is more susceptible to the DNA damaging agent, methyl methane sulphonate, than the control line. Therefore, our study suggests that ASF1 from Leishmania pertains to the chromatin remodelling machinery of the parasite and acts on its response to DNA damage.

  2. The FML (Fucose Mannose Ligand) of Leishmania donovani: a new tool in diagnosis, prognosis, transfusional control and vaccination against human kala-azar

    Scientific Electronic Library Online (English)

    Claris B. Palatnik de, Sousa; Elza M., Gomes; Edilma Paraguai de, Souza; Wania R. dos, Santos; Sirley R. de, Macedo; Linnete V. de, Medeiros; Kleber, Luz.

    1996-04-01

    Full Text Available O FML (Ligame de Fucose-Manose) de Leishmania donovani é uma fração glicoproteica complexa. O seu potencial no diagnóstico da leishmaniose visceral humana foi testado com soros provenientes de Natal, Rio Grande do Norte, Brasil. O teste de FML-ELISA mostrou 100% de sensibilidade e 96% de especificid [...] ade, identificando pacientes com calazar declarado (p Abstract in english The Fucose-Mannose Ligand (FML) of Leishmania donovani is a complex glycoproteic fraction. Its potential use as a tool for diagnosis of human visceral leishmaniasis was tested with human sera from Natal, Rio Grande do Norte, Brazil. The FML-ELISA test, showed 100% sensitivity and 96% specificity, id [...] entifying patients with overt kala-azar (p

  3. Study of Functionalized Gold Nanoparticles with Anti-gp63 IgG Antibody for the Detection of Glycoprotein gp63 in Membrane Surface of Leishmania Genus Parasites

    Directory of Open Access Journals (Sweden)

    Alberto Fernández

    2013-07-01

    Full Text Available In this work we present the preparation and functionalization of gold nanoparticles (AuNPs for the detection of presence of gp63 glycoprotein in the surface of Leishmania genus parasites. AuNPs were prepared by induced laser ablation in a clean and biologically suitable media. The nanoparticles were functionalized with anti-gp63 lgG antibody in order to study the interaction with the glycoprotein component gp63 (63 kDa present on the membrane surface of Leishmania genus parasites. The functionalized AuNPs showed potential as a spectrometric indicator of the parasite existence, both by the detection of the presence of the gp63 in solution and through the specific interaction with the parasites in vitro. The specificity of the study opens a new line of research on the use of modified nanoparticles in the development of a fast and easy assay for Leishmaniosis diagnostics.

  4. Respuesta inmune a la infección por Leishmania infantum en caninos - Immune response to infection by Leishmania infantum in dogs

    Directory of Open Access Journals (Sweden)

    Rodríguez Villamizar, Irlene Evelyne

    2009-11-01

    Full Text Available ResumenLa leishmaniasis visceral canina (LVC es una enfermedad infecciosaclásicamente asociada al protozoo Leishmania spp, que se manifiestacon un amplio espectro patológico, desde infecciones asintomáticashasta procesos viscerales fatales. El control de la infección implica el desarrollo de una respuesta inmune protectora, que en el caso de los perros es dicotómica, caracterizada tanto por mecanismos humoralescomo celulares. Los mecanismos humorales involucran anticuerpos ycomplemento mientras que el mecanismo celular implica la activación demacrófagos y linfocitos T con la producción de citocinas. El objetivo de esta revisión es ofrecer un panorama general de los mecanismosinmunológicos, células y moléculas que intervienen durante elestablecimiento de la infección por Leishmania en perros.SummaryCanine Visceral Leishmaniosis (CVL is an infectious disease classicallyassociated with the protozoan Leishmania spp, which cause a broadpathological spectrum, ranging from asymptomatic infection to fatalvisceral processes. Infection control involves the development of aprotective immune response, which in the case of dogs is dichotomous,characterized by both humoral and cellular mechanisms. Humoralmechanisms include antibodies and complement but cellular mechanisminvolved alveolar macrophages and T lymphocytes activation with theproduction of cytokines. The aim of this review is to provide an overview about the immunological mechanisms, cells and moleculesinvolved during the establishment of the Leishmania infection in dogs.

  5. Alta prevalencia de infección por Leishmania (Kinetoplastidae: Trypanosomatidae) en perros del norte de Colombia / High prevalence of infection with Leishmania (Kinetoplastea: Trypanosomatidae) in dogs in northern Colombia

    Scientific Electronic Library Online (English)

    Margaret Paternina, Gómez; Yirys, Díaz-Olmos; Luis Enrique, Paternina; Eduar Elías, Bejarano.

    2013-09-01

    Full Text Available Introducción. Aunque el perro se considera el principal reservorio doméstico de Leishmania infantum en varios países de Latinoamérica, se desconocen las tasas de infección por parásitos del género Leishmania en perros de algunos focos de leishmaniasis visceral del norte de Colombia. Objetivo. Establ [...] ecer las tasas de infección por Leishmania spp. en poblaciones caninas del departamento de Sucre en el norte de Colombia. Materiales y métodos. Se estudiaron perros de zonas rurales de los municipios de Sincelejo, Sampués y Ovejas. Los parásitos del género Leishmania se detectaron mediante la amplificación de un segmento de ADN de la subunidad ribosómica pequeña (rSSU). Se analizó la relación entre variables como sexo, grupos etarios y presencia de signos clínicos, respecto a la infección por Leishmania . Resultados. Se amplificó un fragmento de 561 pb de la rSSU de Leishmania spp. en 34,9 % (29/83), 35,7 % (15/42) y 11,1 % (1/9) de los perros analizados de Sincelejo, Sampués y Ovejas, respectivamente. La prevalencia total de infección por Leishmania spp. fue de 33,6 %. En dos perros de Sincelejo, dos de Sampués y uno de Ovejas, se obtuvo una banda de 650 pb, característica de parásitos del género Trypanosoma . El 64,2 % de los perros que mostraron al menos un signo clínico indicativo de leishmaniasis canina, fue positivo por PCR. Se halló una relación estadísticamente significativa entre los perros mayores de 33 meses de edad y el resultado positivo para Leishmania spp. (p=0,043). No se encontró relación entre el sexo del perro y el resultado positivo para Leishmania spp. (p=0,85) . Conclusión. Un tercio de la población canina analizada se encontró infectada con parásitos del género Leishmania , lo cual podría sustentar su posible papel como fuente de infección para el insecto vector. Abstract in english Introduction: Although the dog is considered to be the main domestic reservoir of Leishmania infantum in several Latin American countries, the rate of infection with Leishmania parasites remains unknown in dogs from foci of visceral leishmaniasis of northern of Colombia. Objetive: To determine the p [...] revalence of Leishmania infection in canine population from department of Sucre in northern Colombia. Materials and methods: The canine population of rural areas of the municipalities of Sincelejo, Sampués and Ovejas was studied. Parasites of the genus Leishmania were detected by amplifying a DNA segment of the small ribosomal subunit (rSSU). The relationship among sex, age group and clinical signs with infection by Leishmania was analyzed. Results: A 561 bp fragment of the Leishmania rSSU was amplified in 34.9% (29/83), 35.7% (15/42) and 11.1% (1/9) of the dogs analyzed from Sincelejo, Sampués and Ovejas, respectively. Overall prevalence of Leishmania infection was 33.6%. A 650 bp band, characteristic of parasites of the genus Trypanosoma, was amplified in two dogs from Sincelejo and Sampués and in one dog from Ovejas. The 64.2% of the dogs that showed clinical signs compatible with canine leishmaniasis, was PCRpositive. A statistically significant relationship was found between dogs over 33 months old and positivity to Leishmania (p=0.043). No relationship was observed between sex and positivity to Leishmania (p=0.85) . Conclusion: A third of the canine population studied is infected with Leishmania , which could support its potential role as a source of infection for the insect vector.

  6. Susceptibility of Cebus apella monkey (Primates: Cebidae) to experimental Leishmania (L.) infantum chagasi-infection / Susceptibilidade do macaco Cebus apella (Primata: Cebidae) à infecção experimental por Leishmania (L.) infantum chagasi

    Scientific Electronic Library Online (English)

    Liliane Almeida, Carneiro; Fernando Tobias, Silveira; Marliane Batista, Campos; Maria do Carmo de Oliveira, Brígido; Claudia Maria C., Gomes; Carlos E.P., Corbett; Márcia D., Laurenti.

    2011-02-01

    Full Text Available Na Amazônia Brasileira, o macaco Cebus apella (Primata: Cebidae) tem sido associado com o ciclo enzoótico da Leishmania (V.) shawi, um parasito dermotrópico causador da Leishmaniose Tegumentar Americana (LTA). Ele tem sido também empregado com sucesso como modelo experimental para estudo da leishman [...] iose tegumentar. Neste trabalho, foi investigada sua susceptibilidade à infecção experimental por Leishmania (L.) infantum chagasi, o agente etiológico da Leishmaniose Visceral Americana (LVA). Foram usados dez espécimes de C. apella oito adultos e dois jovens, quatro machos e seis fêmeas, todos nascidos e criados em cativeiro. Dois protocolos de infecção experimental foram feitos: i) seis macacos foram inoculados por via intradérmica (ID), na base da cauda com 2x10(6) formas promastigotas em fase estacionária de crescimento; ii) outros quatro macacos foram inoculados com 3x10(7) formas amastigotas de infecção visceral de hamsteres por duas vias diferentes: a) dois por via intravenosa (IV) e, b) outros dois pela via intraperitoneal (IP). A avaliação da infecção incluiu parâmetros: clínico: exame físico do abdômen, peso e temperatura corporal; b) parasitológico: aspirado de medula óssea por agulha para procura de amastigotas (esfregaço corado por Giemsa) e formas promastigotas (meio de cultura); c) imunológico: Reação de Imunofluorescência Indireta (RIFI) e, resposta de hipersensibilidade tardia (DTH). Nos seis macacos inoculados ID (formas promastigotas) todos os parâmetros de avaliação da infecção foram negativos durante o período de 12 meses. Entre os quatro macacos inoculados com formas amastigotas, dois inoculados IV mostraram parasitos na medula óssea do primeiro ao sexto mês p.i. e em seguida houve a resolução da infecção, no entanto os outros dois inoculados IP foram totalmente negativos. Esses quatro macacos apresentaram resposta específica de anticorpo IgG desde o terceiro mês p.i. (IP: 1/80 e IV: 1/320) até o décimo segundo mês (IP: 1/160 e IV: 1/5120). A conversão DTH ocorreu em apenas um macaco inoculado IV com uma forte reação na pele (30 mm). Considerando esses resultados, nós não recomendamos o uso do macaco C. apella como modelo animal para estudo da LVA. Abstract in english In Amazonian Brazil, the Cebus apella monkey (Primates: Cebidae) has been associated with the enzootic cycle of Leishmania (V.) shawi, a dermotropic parasite causing American cutaneous leishmaniasis (ACL). It has also been successfully used as animal model for studying cutaneous leishmaniasis. In th [...] is work, there has been investigated its susceptibility to experimental Leishmania (L.) infantum chagasi-infection, the etiologic agent of American visceral leishmaniasis (AVL). There were used ten C. apella specimens, eight adult and two young, four males and six females, all born and raised in captivity. Two experimental infection protocols were performed: i) six monkeys were inoculated, intra-dermal via (ID), into the base of the tail with 2 x 10(6) promastigotes forms from the stationary phase culture medium; ii) other four monkeys were inoculated with 3 x 10(7) amastigotes forms from the visceral infection of infected hamsters by two different via: a) two by intravenous via (IV) and, b) other two by intra-peritoneal via (IP). The parameters of infection evaluation included: a) clinical: physical exam of abdomen, weigh and body temperature; b) parasitological: needle aspiration of the bone-marrow for searching of amastigotes (Giemsa-stained smears) and promastigotes forms (culture medium); c) immunological: Indirect fluorescence antibody test (IFAT) and, Delayed-type hypersensitivity (DTH). In the six monkeys ID inoculated (promastigotes forms) all parameters of infection evaluation were negative during the 12 months period of follow-up. Among the four monkeys inoculated with amastigotes forms, two IV inoculated showed the parasite in the bone-marrow from the first toward to the sixth month p.i. and following that they cleared the infection, whereas the oth

  7. The Multiple Forms of Leishmania major in BALB/C Mice Lung in Iran

    OpenAIRE

    Jafari, M.; Sh Shirbazou

    2012-01-01

    Cutaneous leishmaniasis is one of the most important parasitic diseases, which are endemic in different parts of Iran. Leishmania major and L. tropica are the primary causative agents of this disease. The aim of the present study was to detect the multiple forms of L. major in lung. Ppromastigotes of L. major at stationary phase were injected to BALB/c mice. After 60 days, the different forms of Leishmania parasites were checked in lung tissue. Promastigote and amastigote forms of Leishmania ...

  8. Translational Control through eIF2alpha Phosphorylation during the Leishmania Differentiation Process

    OpenAIRE

    Cloutier, Serge; Laverdie?re, Maxime; Chou, Marie-noelle; Boilard, Nathalie; Chow, Conan; Papadopoulou, Barbara

    2012-01-01

    The parasitic protozoan Leishmania alternates between an invertebrate and a mammalian host. Upon their entry to mammalian macrophages, Leishmania promastigotes differentiate into amastigote forms within the harsh environment of the phagolysosomal compartment. Here, we provide evidence for the importance of translational control during the Leishmania differentiation process. We find that exposure of promastigotes to a combined elevated temperature and acidic pH stress, a key signal triggering ...

  9. Molecular Cloning and Expression of Iranian Leishmania major Pteridine Reductase 1

    OpenAIRE

    N Mosaffa; Mohebali, M; F Mahboudi; A. Haghighi; M. Bandehpour; Kheirandish, F; B KAZEMI

    2008-01-01

    Background: Leishmaniasis is an endemic disease in 88 countries. Reports on Leishmania drug resistance are growing in number. The mechanism of unresponsiveness against glucantime in Iranian cutaneous leishmaniasis has not yet been characterized. To begin the first step in finding an anti-Leishmania chemotherapy, we prepared recombinant L. major PTR1 enzyme and characterized its activity by enzymatic assay. Methods: Leishmania promastigote DNA was extracted and the ptr1 gene amplified using sp...

  10. Leishmania ?-1,2-mannan is assembled on a mannose-cyclic phosphate primer

    OpenAIRE

    Sernee, M. Fleur; Ralton, Julie E.; Dinev, Zoran; Khairallah, George N.; O’hair, Richard A.; Williams, Spencer J.; Mcconville, Malcolm J.

    2006-01-01

    Infective stages of the protozoan parasite Leishmania spp. accumulate a class of ?-1,2-mannan oligosaccharides as their major carbohydrate reserve material. Here, we describe the biosynthesis of Leishmania mannan. Mannan precursors were identified by metabolic labeling of Leishmania mexicana promastigotes with [3H]mannose. Label was initially incorporated into a phosphomannose primer and short phosphorylated ?-1,2-mannan oligomers that were two to five residues long. Analysis of the mannan ...

  11. Serological detection of Toxoplasma gondii, Leishmania infantum and Neospora caninum in cats from an area endemic for leishmaniasis in Brazil / Detecção sorológica de Toxoplasma gondii, Leishmania infantum e Neospora caninum em gatos de uma área endêmica para leishmaniose no Brasil

    Scientific Electronic Library Online (English)

    Keyla Carstens Marques de, Sousa; Heitor Miraglia, Herrera; Iara Helena, Domingos; João Bosco Vilela, Campos; Isabela Maria Campanelli dos, Santos; Haroldo Henrique, Neves; Rosangela Zacarias, Machado; Marcos Rogério, André.

    2014-12-01

    Full Text Available O presente estudo teve como objetivo investigar a ocorrência de anticorpos anti-Toxoplasma gondii, Leishmania infantum e Neospora caninum, em 151 gatos, por meio da Reação de Imunofluorescência Indireta (RIFI). Entre os meses de janeiro e abril de 2013, amostras de soro foram coletadas de 151 gatos [...] domésticos (65 gatos errantes e 86 gatos domiciliados; 55 machos e 96 fêmeas), de Campo Grande, Mato Grosso do Sul, Brasil. Anticorpos IgG anti-T. gondii, anti-L. infantum e anti-N. caninum foram encontrados em 49 (32,5%), 34 (22,5%) e 10 (6,6%) gatos amostrados, respectivamente. Verificou-se uma associação estatisticamente significativa entre as infecções por T. gondii e N. caninum, T. gondii e L. infantum e N. caninum e Leishmania infantum (p Abstract in english An investigation was made into the occurrence of antibodies to Toxoplasma gondii, Leishmania infantum and Neospora caninum in 151 domestic cats, based on the indirect fluorescent antibody test (IFAT). Serum samples were collected from 151 domestic cats (65 free-roaming and 86 domiciled cats; 55 male [...] s and 96 females) in Campo Grande, Mato Grosso do Sul, Brazil between January and April 2013. IgG antibodies to T. gondii, L. infantum and N. caninum were found, respectively, in 49 (32.5%), 34 (22.5%) and 10 (6.6%) sampled cats. A positive correlation was found between T. gondii and N. caninum, T. gondii and L. infantum, and N. caninum and L. infantum (p

  12. Susceptibility of Cebus apella monkey (Primates: Cebidae to experimental Leishmania (L. infantum chagasi-infection Susceptibilidade do macaco Cebus apella (Primata: Cebidae à infecção experimental por Leishmania (L. infantum chagasi

    Directory of Open Access Journals (Sweden)

    Liliane Almeida Carneiro

    2011-02-01

    Full Text Available In Amazonian Brazil, the Cebus apella monkey (Primates: Cebidae has been associated with the enzootic cycle of Leishmania (V. shawi, a dermotropic parasite causing American cutaneous leishmaniasis (ACL. It has also been successfully used as animal model for studying cutaneous leishmaniasis. In this work, there has been investigated its susceptibility to experimental Leishmania (L. infantum chagasi-infection, the etiologic agent of American visceral leishmaniasis (AVL. There were used ten C. apella specimens, eight adult and two young, four males and six females, all born and raised in captivity. Two experimental infection protocols were performed: i six monkeys were inoculated, intra-dermal via (ID, into the base of the tail with 2 x 10(6 promastigotes forms from the stationary phase culture medium; ii other four monkeys were inoculated with 3 x 10(7 amastigotes forms from the visceral infection of infected hamsters by two different via: a two by intravenous via (IV and, b other two by intra-peritoneal via (IP. The parameters of infection evaluation included: a clinical: physical exam of abdomen, weigh and body temperature; b parasitological: needle aspiration of the bone-marrow for searching of amastigotes (Giemsa-stained smears and promastigotes forms (culture medium; c immunological: Indirect fluorescence antibody test (IFAT and, Delayed-type hypersensitivity (DTH. In the six monkeys ID inoculated (promastigotes forms all parameters of infection evaluation were negative during the 12 months period of follow-up. Among the four monkeys inoculated with amastigotes forms, two IV inoculated showed the parasite in the bone-marrow from the first toward to the sixth month p.i. and following that they cleared the infection, whereas the other two IP inoculated were totally negative. These four monkeys showed specific IgG-antibody response since the third month p.i. (IP: 1/80 and IV: 1/320 IgG toward to the 12th month (IP: 1/160 and IV: 1/5120. The DTH-conversion occurred in only one IV inoculated monkey with a strong (30 mm skin reaction. Considering these results, we do not encourage the use of C. apella monkey as animal model for studying the AVL.Na Amazônia Brasileira, o macaco Cebus apella (Primata: Cebidae tem sido associado com o ciclo enzoótico da Leishmania (V. shawi, um parasito dermotrópico causador da Leishmaniose Tegumentar Americana (LTA. Ele tem sido também empregado com sucesso como modelo experimental para estudo da leishmaniose tegumentar. Neste trabalho, foi investigada sua susceptibilidade à infecção experimental por Leishmania (L. infantum chagasi, o agente etiológico da Leishmaniose Visceral Americana (LVA. Foram usados dez espécimes de C. apella oito adultos e dois jovens, quatro machos e seis fêmeas, todos nascidos e criados em cativeiro. Dois protocolos de infecção experimental foram feitos: i seis macacos foram inoculados por via intradérmica (ID, na base da cauda com 2x10(6 formas promastigotas em fase estacionária de crescimento; ii outros quatro macacos foram inoculados com 3x10(7 formas amastigotas de infecção visceral de hamsteres por duas vias diferentes: a dois por via intravenosa (IV e, b outros dois pela via intraperitoneal (IP. A avaliação da infecção incluiu parâmetros: clínico: exame físico do abdômen, peso e temperatura corporal; b parasitológico: aspirado de medula óssea por agulha para procura de amastigotas (esfregaço corado por Giemsa e formas promastigotas (meio de cultura; c imunológico: Reação de Imunofluorescência Indireta (RIFI e, resposta de hipersensibilidade tardia (DTH. Nos seis macacos inoculados ID (formas promastigotas todos os parâmetros de avaliação da infecção foram negativos durante o período de 12 meses. Entre os quatro macacos inoculados com formas amastigotas, dois inoculados IV mostraram parasitos na medula óssea do primeiro ao sexto mês p.i. e em seguida houve a resolução da infecção, no entanto os outros dois inoculados IP foram totalmente negativos. Esses quatro macacos apresentaram resposta específic

  13. Efecto de la diminacina en hámsteres inoculados con Leishmania chagasi

    Scientific Electronic Library Online (English)

    A.N, Burna; M.S, Catuogno; M, Sánchez Negrette; A, Mirad; O.A, Maccio.

    2013-12-01

    Full Text Available La leishmaniosis es una enfermedad causada por protozoarios del género Leishmania, que afecta al hombre y animales a través de la picadura de insectos infectados. La diminacina es una droga con actividad in vitro inhibitoria del crecimiento de Leishmania donovani; también ha sido utilizada para el t [...] ratamiento contra tripanosomosis y babesiosis. El objetivo del presente trabajo fue comprobar el efecto de diminacina in vivo como tratamiento antileishmaniásico en hámsteres, y en caso afirmativo transpolarla como alternativa terapéutica para el control y posible erradicación de la leishmaniosis en caninos. Se utilizaron 26 hámsteres agrupados en cuatro lotes de 6-7 animales cada uno: (a) inyectados con diminacina, (b) inoculados con Leishmania chagasi, (c) inoculados con L. chagasi e inyectados con diminacina, y (d) controles. La inoculación se efectuó con un macerado de bazo extraído de un canino naturalmente infectado con L. chagasi. La diminacina fue administrada a razón de 3,5 mg/kg vía IM. Los frotis y cortes histopatológicos de los hámsteres infectados revelaron amastigotes de L. chagasi. Los ejemplares infectados y tratados con diminacina mantuvieron un mejor estado de salud que aquéllos privados de tratamiento, lo cual sugiere que la droga tendría un efecto benéfico en el organismo del animal infectado. Abstract in english Leishmaniosis is a disease caused by protozoa of the genus Leishmania, which is transmitted to human beings by the bite of infected insects. Diminazine is a drug with proven in vitro growth inhibition activity of Leishmania donovani and has also been used for the treatment against trypanosomosis and [...] other parasitic diseases. The aim of this study was to determine the effect of diminazine in vivo as an antileishmanial drug in hamsters for the possible extrapolation and thus potential use as a therapeutic alternative in dogs. Twenty six hamsters were divided into four groups, two groups of 6 animals each, and two groups of 7 each. Some animals were inoculated IM with macerated spleen from a dog naturally infected with Leishmania chagasi. The diminazine treated group and the control animals inoculated with the protozoa presented amastigotes of L. chagasi in smears and in histopathological sections. Diminazine treated animals remained in better health state unlike the control group inoculated with L. chagasi. Results suggest that diminazine would have a benefcial effect in infected dogs.

  14. High throughput screens yield small molecule inhibitors of Leishmania CRK3:CYC6 cyclin-dependent kinase

    OpenAIRE

    Walker, RG; Thomson, G; Malone, K.; Nowicki, MW; Brown, E (Elizabeth); Blake, DG; Turner, NJ; Walkinshaw, MD; Grant, KM; Mottram, JC; Kita, K.

    2011-01-01

    Background: Leishmania species are parasitic protozoa that have a tightly controlled cell cycle, regulated by cyclin-dependent kinases (CDKs). Cdc2-related kinase 3 (CRK3), an essential CDK in Leishmania and functional orthologue of human CDK1, can form an active protein kinase complex with Leishmania cyclins CYCA and CYC6. Here we describe the identification and synthesis of specific small molecule inhibitors of bacterially expressed Leishmania CRK3: CYC6 using a high throughput screening as...

  15. Cutaneous leishmaniasis caused by Leishmania infantum transmitted by Phlebotomus tobbi.

    Science.gov (United States)

    Svobodová, Milena; Alten, Bulent; Zídková, Lenka; Dvorák, Vít; Hlavacková, Jitka; Mysková, Jitka; Seblová, Veronika; Kasap, Ozge Erisoz; Belen, Asli; Votýpka, Jan; Volf, Petr

    2009-01-01

    Transmission of cutaneous leishmaniasis (CL) caused by Leishmania infantum was studied in South Anatolia, Turkey. Small, non-ulcerating lesions prevailed and patients were negative in rK39 tests for antibody detection for human visceral leishmaniasis (VL). The most abundant sand fly species, Phlebotomus tobbi, was found positive for Leishmania promastigotes with a prevalence of 1.4% (13 out of 898 dissected females). The isolated strains were identical with those obtained from patients with CL and were typed as L. infantum. Phylogenetic analysis revealed similarity to MON-188 and a clear difference from the MON-1 clade. Blood-meal identification showed that P. tobbi feeds preferentially on cattle and humans. This finding, the high number of CL patients and relative scarcity of dogs in the focus, suggests that the transmission cycle could be anthroponotic. PMID:18761342

  16. Human cutaneous leishmaniasis caused by Leishmania (Viannia braziliensis in Santiago del Estero, Argentina: identification of parasites by monoclonal antibodies and isoenzymes Leishmaniose cutânea humana causada por Leishmania (Viannia braziliensis na Província de Santiago del Estero, Argentina: identificação dos parasitas por anticorpos monoclonais e isoenzimas

    Directory of Open Access Journals (Sweden)

    C.A. Cuba Cuba

    1996-12-01

    Full Text Available Diagnostic and parasite characterization and identification studies were carried out in human patients with cutaneous leishmaniasis lesions in Santiago del Estero, Northern Province of Argentina. Diagnostic procedures were biopsies of lesions for smears and inoculations in hamster, needle aspirations of material from ulcers for "in vitro" cultures. Immunodiagnostic techniques applied were IFAT-IgG and Montenegro skin test. Primary isolation of eight stocks of leishmanial parasites was achieved from patients with active lesions. All stocks were biologically characterized by their behaviour in hamster, measurements of amastigote and promastigotes and growth "in vitro". Eight stocks were characterized and identified at species level by their reactivity to a cross-panel of sub-genus and specie-specific Monoclonal Antibodies through an Indirect Immunofluorescence technique and a Dot-ELISA. We conclude from the serodeme analysis of Argentina stocks that: stocks MHOM/AR/92/SE-1; SE-2; SE-4; SE-8; SE-8-I; SE-30; SE-34 and SE-36 are Leishmania (Viannia braziliensis. Three Leishmania stocks (SE-1; SE-2 and SE-30 did not react with one highly specie-specific Monoclonal Antibody (Clone: B-18, Leishmania (Viannia braziliensis marker disclosing two serodeme group patterns. Five out of eight soluble extracts of leishmanial promastigotes were electrophoresed on thin-layer starch gels and examined for the enzyme MPI, Mannose Phosphate Isomerase; MDH, Malate Dehydrogenase; 6PGD, 6 Phosphogluconate Dehydrogenase; NH, Nucleoside Hydrolase, 2-deoxyinosinc as substrate; SOD, Superoxide Dismutase; GPI, Glucose Phosphate Isomerase and ES, Esterase. From the isoenzyme studies we concluded that stocks: MHOM/AR/92/SE-1; SE-2; SE-4; SE-8 and SE-8-I are isoenzymatically Leishmania (Viannia braziliensis. We need to analyze more enzymes before assigning them to a braziliensis zymodeme.Estudos de diagnóstico, caracterização parasitária e identificação foram conduzidos em pacientes humanos com lesões cutâneas de leishmaniose na Província de Santiago del Estero, no Norte da Argentina. Os procedimentos de diagnóstico foram: biópsias de lesões para utilização em esfregaços e inoculação em hamster; aspiração (com agulha de úlceras, para cultura "in vitro". As técnicas imunodiagnósticas empregadas foram a IFAT-IgG e o teste intradérmico de Montenegro. Oito cepas de parasitas foram isoladas, sendo estas obtidas de pacientes com lesões ativas. Todas as cepas foram inicialmente caracterizadas biologicamente por seu comportamento na infecção experimental do hamster, mensuração dos amastigotas e promastigotas e crescimento "in vitro". As mesmas oito cepas foram logo identificadas e caracterizadas a nível de espécie, devido a sua reatividade frente a um painel de anticorpos monoclonais subgênero e espécie-específicos. Isso foi realizado utilizando o teste de Imunofluorescência Indireta (IFAT/MAbs e de um procedimento de Dot-ELISA. Nós concluímos a partir da análise de serodema dos isolados argentinos que: MHOM/AR/92/SE-1; SE-2; SE-4; SE-8; SE-8-I; SE-30; SE-34 e SE-36 são Leishmania (Viannia braziliensis. Entretanto, três dos isolados de Leishmania (SE-1; SE-2 e SE-30 não foram reconhecidos quando testados com um anticorpo monoclonal de reconhecida alta espécie-especificidade (clone B-18, marcador consagrado de Leishmania (Viannia braziliensis, revelando a existência de dois tipos de serodemas entre as cepas estudadas. Cinco dos oito extratos solúveis de Leishmania foram submetidos à eletroforese em gel de amido de camada fina e subseqüentemente examinadas a fim de constatar a atividade das enzimas MPI, MDH, 6PGD, NH, NH-D, SOD, GPI e ES. Fundamentados nos estudos dos corridos eletroforéticos obtidos nos ensaios isoenzimáticos chegamos à conclusão que as cepas MHOM/AR/92 SE-1; SE-2; SE-4; SE-8 e SE-8-I são Leishmania (Viannia braziliensis. É necessário analisar mais enzimas antes de enquadrá-los nos zymodema braziliensis

  17. Human cutaneous leishmaniasis caused by Leishmania (Viannia) braziliensis in Santiago del Estero, Argentina: identification of parasites by monoclonal antibodies and isoenzymes / Leishmaniose cutânea humana causada por Leishmania (Viannia) braziliensis na Província de Santiago del Estero, Argentina: identificação dos parasitas por anticorpos monoclonais e isoenzimas

    Scientific Electronic Library Online (English)

    C.A., Cuba Cuba; C.O., Torno; O., Ledesma; E., Visciarelli; S., Garcia; M.I., Prat; R., Costamagna; L., Barbieri; D.A., Evans.

    1996-12-01

    Full Text Available Estudos de diagnóstico, caracterização parasitária e identificação foram conduzidos em pacientes humanos com lesões cutâneas de leishmaniose na Província de Santiago del Estero, no Norte da Argentina. Os procedimentos de diagnóstico foram: biópsias de lesões para utilização em esfregaços e inoculaçã [...] o em hamster; aspiração (com agulha) de úlceras, para cultura "in vitro". As técnicas imunodiagnósticas empregadas foram a IFAT-IgG e o teste intradérmico de Montenegro. Oito cepas de parasitas foram isoladas, sendo estas obtidas de pacientes com lesões ativas. Todas as cepas foram inicialmente caracterizadas biologicamente por seu comportamento na infecção experimental do hamster, mensuração dos amastigotas e promastigotas e crescimento "in vitro". As mesmas oito cepas foram logo identificadas e caracterizadas a nível de espécie, devido a sua reatividade frente a um painel de anticorpos monoclonais subgênero e espécie-específicos. Isso foi realizado utilizando o teste de Imunofluorescência Indireta (IFAT/MAbs) e de um procedimento de Dot-ELISA. Nós concluímos a partir da análise de serodema dos isolados argentinos que: MHOM/AR/92/SE-1; SE-2; SE-4; SE-8; SE-8-I; SE-30; SE-34 e SE-36 são Leishmania (Viannia) braziliensis. Entretanto, três dos isolados de Leishmania (SE-1; SE-2 e SE-30) não foram reconhecidos quando testados com um anticorpo monoclonal de reconhecida alta espécie-especificidade (clone B-18, marcador consagrado de Leishmania (Viannia) braziliensis), revelando a existência de dois tipos de serodemas entre as cepas estudadas. Cinco dos oito extratos solúveis de Leishmania foram submetidos à eletroforese em gel de amido de camada fina e subseqüentemente examinadas a fim de constatar a atividade das enzimas MPI, MDH, 6PGD, NH, NH-D, SOD, GPI e ES. Fundamentados nos estudos dos corridos eletroforéticos obtidos nos ensaios isoenzimáticos chegamos à conclusão que as cepas MHOM/AR/92 SE-1; SE-2; SE-4; SE-8 e SE-8-I são Leishmania (Viannia) braziliensis. É necessário analisar mais enzimas antes de enquadrá-los nos zymodema braziliensis Abstract in english Diagnostic and parasite characterization and identification studies were carried out in human patients with cutaneous leishmaniasis lesions in Santiago del Estero, Northern Province of Argentina. Diagnostic procedures were biopsies of lesions for smears and inoculations in hamster, needle aspiration [...] s of material from ulcers for "in vitro" cultures. Immunodiagnostic techniques applied were IFAT-IgG and Montenegro skin test. Primary isolation of eight stocks of leishmanial parasites was achieved from patients with active lesions. All stocks were biologically characterized by their behaviour in hamster, measurements of amastigote and promastigotes and growth "in vitro". Eight stocks were characterized and identified at species level by their reactivity to a cross-panel of sub-genus and specie-specific Monoclonal Antibodies through an Indirect Immunofluorescence technique and a Dot-ELISA. We conclude from the serodeme analysis of Argentina stocks that: stocks MHOM/AR/92/SE-1; SE-2; SE-4; SE-8; SE-8-I; SE-30; SE-34 and SE-36 are Leishmania (Viannia) braziliensis. Three Leishmania stocks (SE-1; SE-2 and SE-30) did not react with one highly specie-specific Monoclonal Antibody (Clone: B-18, Leishmania (Viannia) braziliensis marker) disclosing two serodeme group patterns. Five out of eight soluble extracts of leishmanial promastigotes were electrophoresed on thin-layer starch gels and examined for the enzyme MPI, Mannose Phosphate Isomerase; MDH, Malate Dehydrogenase; 6PGD, 6 Phosphogluconate Dehydrogenase; NH, Nucleoside Hydrolase, 2-deoxyinosinc as substrate; SOD, Superoxide Dismutase; GPI, Glucose Phosphate Isomerase and ES, Esterase. From the isoenzyme studies we concluded that stocks: MHOM/AR/92/SE-1; SE-2; SE-4; SE-8 and SE-8-I are isoenzymatically Leishmania (Viannia) braziliensis. We need to analyze more enzymes before assigning them to a braziliensis zymodeme.

  18. Human mixed infections of Leishmania spp. and Leishmania-Trypanosoma cruzi in a sub Andean Bolivian area: identification by polymerase chain reaction/hybridization and isoenzyme

    Scientific Electronic Library Online (English)

    B, Bastrenta; N, Mita; R, Buitrago; F, Vargas; M, Flores; M, Machane; N, Yacsik; M, Torrez; F, Le Pont; F, Brenière.

    2003-03-01

    Full Text Available Parasites belonging to Leishmania braziliensis, Leishmania donovani, Leishmania mexicana complexes and Trypanosoma cruzi (clones 20 and 39) were searched in blood, lesions and strains collected from 28 patients with active cutaneous leishmaniasis and one patient with visceral leishmaniasis. PCR-hybr [...] idization with specific probes of Leishmania complexes (L. braziliensis, L. donovani and L. mexicana) and T. cruzi clones was applied to the different DNA samples. Over 29 patients, 8 (27.6%) presented a mixed infection Leishmania complex species, 17 (58.6%) a mixed infection Leishmania-T. cruzi, and 4 (13.8%) a multi Leishmania-T. cruzi infection. Several patients were infected by the two Bolivian major clones 20 and 39 of T. cruzi (44.8%). The L. braziliensis complex was more frequently detected in lesions than in blood and a reverse result was observed for L. mexicana complex. The polymerase chain reaction-hybridization design offers new arguments supporting the idea of an underestimated rate of visceral leishmanisis in Bolivia. Parasites were isolated by culture from the blood of two patients and lesions of 10 patients. The UPGMA (unweighted pair-group method with arithmetic averages) dendrogram computed from Jaccard's distances obtained from 11 isoenzyme loci data confirmed the presence of the three Leishmania complexes and undoubtedly identified human infections by L. (V.) braziliensis, L. (L.) chagasi and L. (L.) mexicana species. Additional evidence of parasite mixtures was visualized through mixed isoenzyme profiles, L. (V.) braziliensis-L. (L.) mexicana and Leishmania spp.-T. cruzi.The epidemiological profile in the studied area appeared more complex than currently known. This is the first report of parasitological evidence of Bolivian patients with trypanosomatidae multi infections and consequences on the diseases' control and patient treatments are discussed.

  19. Human mixed infections of Leishmania spp. and Leishmania-Trypanosoma cruzi in a sub Andean Bolivian area: identification by polymerase chain reaction/hybridization and isoenzyme

    Directory of Open Access Journals (Sweden)

    B Bastrenta

    2003-03-01

    Full Text Available Parasites belonging to Leishmania braziliensis, Leishmania donovani, Leishmania mexicana complexes and Trypanosoma cruzi (clones 20 and 39 were searched in blood, lesions and strains collected from 28 patients with active cutaneous leishmaniasis and one patient with visceral leishmaniasis. PCR-hybridization with specific probes of Leishmania complexes (L. braziliensis, L. donovani and L. mexicana and T. cruzi clones was applied to the different DNA samples. Over 29 patients, 8 (27.6% presented a mixed infection Leishmania complex species, 17 (58.6% a mixed infection Leishmania-T. cruzi, and 4 (13.8% a multi Leishmania-T. cruzi infection. Several patients were infected by the two Bolivian major clones 20 and 39 of T. cruzi (44.8%. The L. braziliensis complex was more frequently detected in lesions than in blood and a reverse result was observed for L. mexicana complex. The polymerase chain reaction-hybridization design offers new arguments supporting the idea of an underestimated rate of visceral leishmanisis in Bolivia. Parasites were isolated by culture from the blood of two patients and lesions of 10 patients. The UPGMA (unweighted pair-group method with arithmetic averages dendrogram computed from Jaccard's distances obtained from 11 isoenzyme loci data confirmed the presence of the three Leishmania complexes and undoubtedly identified human infections by L. (V. braziliensis, L. (L. chagasi and L. (L. mexicana species. Additional evidence of parasite mixtures was visualized through mixed isoenzyme profiles, L. (V. braziliensis-L. (L. mexicana and Leishmania spp.-T. cruzi.The epidemiological profile in the studied area appeared more complex than currently known. This is the first report of parasitological evidence of Bolivian patients with trypanosomatidae multi infections and consequences on the diseases' control and patient treatments are discussed.

  20. The LPG1 gene family of Leishmania major

    OpenAIRE

    Zhang, Kai; Barron, Tamara; Salvatore J. Turco; Beverley, Stephen M.

    2004-01-01

    In Leishmania major, the core of the abundant surface lipophosphoglycan (LPG) is structurally related to that of the smaller glycosylinositolphospholipids (GIPLs) in containing galactosylfuranose (Galf ) residues in a Galf (?1, 3)Man motif. However, deletion of the putative Galf-transferase (Galf T) LPG1 affected Galf incorporation in LPG but not GIPLs. We hypothesized that the presumptive GIPL Galf-transferases could be homologous to LPG1, and identified three related genes in the L. major ...

  1. Leishmania donovani Lipophosphoglycan : Modulation of Macrophage and Dendritic Cell Function

    OpenAIRE

    Tejle, Katarina

    2006-01-01

    Leishmania donovani is a blood-borne tropicial parasite, which infects humans through bites by Phlebotomus sandflies. The parasite survives and multiplies inside macrophages in inner organs, and causes the deadly disease visceral leishmaniasis (Kala-Azar). Macrophages and dendritic cells (DC) are professional antigen-presenting cells involved in the initiation of immune responses. Immature DC are present in all tissues where they internalise and process antigen, in response to which they migr...

  2. Leishmania promastigotes: building a safe niche within macrophages

    OpenAIRE

    Moradin, Neda; Descoteaux, Albert

    2012-01-01

    Upon their internalization by macrophages, Leishmania promastigotes inhibit phagolysosome biogenesis. The main factor responsible for this inhibition is the promastigote surface glycolipid lipophosphoglycan (LPG). This glycolipid has a profound impact on the phagosome, causing periphagosomal accumulation of F-actin and disruption of phagosomal lipid microdomains. Functionally, this LPG-mediated inhibition of phagosome maturation is characterized by an impaired assembly of the NADPH oxidase an...

  3. Purine salvage in Leishmania: complex or simple by design?

    OpenAIRE

    Boitz, Jan M.; Ullman, Buddy; Jardim, Armando; Carter, Nicola S.

    2012-01-01

    Purine nucleotides function in a variety of vital cellular and metabolic processes including energy production, cell signaling, synthesis of vitamin-derived cofactors and nucleic acids, and as determinants of cell fate. Unlike their mammalian and insect hosts, Leishmania cannot synthesize the purine ring de novo and are absolutely dependent upon them to meet their purine requirements. The obligatory nature of purine salvage in these parasites, therefore, offers an attractive paradigm for drug...

  4. Trafficking and release of Leishmania metacyclic HASPB on macrophage invasion

    OpenAIRE

    MacLean, Lorna M; O'Toole, Peter J; Stark, Meg; Marrison, Jo; Seelenmeyer, Claudia; Nickel, Walter; Deborah F. Smith

    2012-01-01

    Proteins of the Leishmania hydrophilic acylated surface protein B (HASPB) family are only expressed in infective parasites (both extra- and intracellular stages) and, together with the peripheral membrane protein SHERP (small hydrophilic endoplasmic reticulum-associated protein), are essential for parasite differentiation (metacyclogenesis) in the sand fly vector. HASPB is a ‘non-classically’ secreted protein, requiring N-terminal acylation for trafficking to and exposure on the plasma me...

  5. Deception and Manipulation: The Arms of Leishmania, a Successful Parasite

    OpenAIRE

    Ceci?lio, Pedro; Pe?rez-cabezas, Begon?a; Santare?m, Nuno; Maciel, Joana; Rodrigues, Vasco; Cordeiro Da Silva, Anabela

    2014-01-01

    Leishmania spp. are intracellular parasitic protozoa responsible for a group of neglected tropical diseases, endemic in 98 countries around the world, called leishmaniasis. These parasites have a complex digenetic life cycle requiring a susceptible vertebrate host and a permissive insect vector, which allow their transmission. The clinical manifestations associated with leishmaniasis depend on complex interactions between the parasite and the host immune system. Consequently, leishmaniasis ca...

  6. Microbial stasis of Leishmania enriettii in activated guinea pig macrophages

    International Nuclear Information System (INIS)

    Peritoneal exudate cells (PEC) from Leishmania-sensitized guinea pigs were cultured in vitro in the presence (activated) or absence (non-activated) of leishmanial antigen for 24 or 48 hours. These were then labelled with 51Cr and challenged with 125I-labelled promastigotes. The changing relationship between the macrophage and the parasite was monitored by observing changes in the ratio of the cell-associated isotopes. Highly significant differences in the ratio change developed during culture. These differences were a result of the activated cultures showing a higher release of 51Cr and a lower release of 125I when compared with the non-activated cells, at 12 hours the percentage release of 125I from the parasite within the activated macrophage was fourfold less than that released by parasites within non-activated cells (9.2% versus 38.3%) and tenfold less than that released from glutaraldehyde-killed organisms phagocytosed by activated macrophages (91.6%). These studies indicate that stasis rather than killing of leishmaniae occurs in the activated macrophage in vitro. Parallel experiments evaluated by the visual counting of leishmaniae within the macrophages support these data. PEC from tuberculin-sensitized guinea pigs activated in vitro by purified protein derivative showed little or no activity against leishmaniae, indicating a specific requirement for this microbial stasis by activated macrophages. As a corostasis by activated macrophages. As a corollary of this, peritoneal exudate lymphocytes separated from the same preparations of PEC were shown to be specifically reactive to leishmanial antigen by transformation and incorporation of 3H-thymidine. (author)

  7. Purificación de dos proteínas de Leishmania Viannia panamensis y su utilización en el diagnóstico de casos de leishmaniosis cutánea de larga evolución y difícil diagnóstico parasitológico

    Directory of Open Access Journals (Sweden)

    Sonia Agudelo

    2001-04-01

    Full Text Available

    La respuesta inmune humoral inducida por Leishmania spp, se inicia desde la etapa temprana de la infección y se mantiene hasta cuando la mayoría de los parásitos son eliminados. Los isotipos, subclases y niveles de anticuerpos que evalúan esta respuesta dependen en gran medida de la forma clínica y el estado de evolución de la enfermedad. En casos de lesiones mucosas o cutáneas de larga evolución donde la posibilidad de encontrar parásitos es baja, toma gran importancia evaluar esta respuesta humoral. Sin embargo, las técnicas serológicas existentes para detectar anticuerpos antileishmania presentan baja sensibilidad y alta reacción cruzada con parásitos de Trypanosoma cruzi, surgiendo, como una alternativa para mejorar estas pruebas, el uso de antígenos proteicos purificados (1,2. Teniendo como base los resultados obtenidos por Agudelo y col (3, quienes demostraron que las fracciones proteicas de 36 y 50 kDa de Leishmania Viannia panamensis son altamente sensibles y
    100% específicas de Leishmania, nos proponemos purificar estas proteínas a fin de utilizarlas para mejorar la sensibilidad y especificidad de pruebas serológicas que sean económicas y de ejecución práctica en zonas endémicas de leishmaniosis.

     

  8. Comprehensive proteomics analysis of glycosomes from Leishmania donovani.

    Science.gov (United States)

    Jamdhade, Mahendra D; Pawar, Harsh; Chavan, Sandip; Sathe, Gajanan; Umasankar, P K; Mahale, Kiran N; Dixit, Tanwi; Madugundu, Anil K; Prasad, T S Keshava; Gowda, Harsha; Pandey, Akhilesh; Patole, Milind S

    2015-03-01

    Leishmania donovani is a kinetoplastid protozoan that causes a severe and fatal disease kala-azar, or visceral leishmaniasis. L. donovani infects human host after the phlebotomine sandfly takes a blood meal and resides within the phagolysosome of infected macrophages. Previous studies on host-parasite interactions have not focused on Leishmania organelles and the role that they play in the survival of this parasite within macrophages. Leishmania possess glycosomes that are unique and specialized subcellular microbody organelles. Glycosomes are known to harbor most peroxisomal enzymes and, in addition, they also possess nine glycolytic enzymes. In the present study, we have carried out proteomic profiling using high resolution mass spectrometry of a sucrose density gradient-enriched glycosomal fraction isolated from L. donovani promastigotes. This study resulted in the identification of 4022 unique peptides, leading to the identification of 1355 unique proteins from a preparation enriched in L. donovani glycosomes. Based on protein annotation, 566 (41.8%) were identified as hypothetical proteins with no known function. A majority of the identified proteins are involved in metabolic processes such as carbohydrate, lipid, and nucleic acid metabolism. Our present proteomic analysis is the most comprehensive study to date to map the proteome of L. donovani glycosomes. PMID:25748437

  9. Crystal structure of Leishmania tarentolae hypoxanthine-guanine phosphoribosyltransferase

    Directory of Open Access Journals (Sweden)

    Oliva Glaucius

    2007-09-01

    Full Text Available Abstract Background Hypoxanthine-guanine phosphoribosyltransferase (HGPRT (EC 2.4.2.8 is a central enzyme in the purine recycling pathway. Parasitic protozoa of the order Kinetoplastida cannot synthesize purines de novo and use the salvage pathway to synthesize purine bases, making this an attractive target for antiparasitic drug design. Results The glycosomal HGPRT from Leishmania tarentolae in a catalytically active form purified and co-crystallized with a guanosine monophosphate (GMP in the active site. The dimeric structure of HGPRT has been solved by molecular replacement and refined against data extending to 2.1 Å resolution. The structure reveals the contacts of the active site residues with GMP. Conclusion Comparative analysis of the active sites of Leishmania and human HGPRT revealed subtle differences in the position of the ligand and its interaction with the active site residues, which could be responsible for the different reactivities of the enzymes to allopurinol reported in the literature. The solution and analysis of the structure of Leishmania HGPRT may contribute to further investigations leading to a full understanding of this important enzyme family in protozoan parasites.

  10. Fitness of Leishmania donovani Parasites Resistant to Drug Combinations

    Science.gov (United States)

    García-Hernández, Raquel; Gómez-Pérez, Verónica; Castanys, Santiago; Gamarro, Francisco

    2015-01-01

    Drug resistance represents one of the main problems for the use of chemotherapy to treat leishmaniasis. Additionally, it could provide some advantages to Leishmania parasites, such as a higher capacity to survive in stress conditions. In this work, in mixed populations of Leishmania donovani parasites, we have analyzed whether experimentally resistant lines to one or two combined anti-leishmanial drugs better support the stress conditions than a susceptible line expressing luciferase (Luc line). In the absence of stress, none of the Leishmania lines showed growth advantage relative to the other when mixed at a 1:1 parasite ratio. However, when promastigotes from resistant lines and the Luc line were mixed and exposed to different stresses, we observed that the resistant lines are more tolerant of different stress conditions: nutrient starvation and heat shock-pH stress. Further to this, we observed that intracellular amastigotes from resistant lines present a higher capacity to survive inside the macrophages than those of the control line. These results suggest that resistant parasites acquire an overall fitness increase and that resistance to drug combinations presents significant differences in their fitness capacity versus single-drug resistant parasites, particularly in intracellular amastigotes. These results contribute to the assessment of the possible impact of drug resistance on leishmaniasis control programs. PMID:25849149

  11. Protection against peroxynitrite by pseudoperoxidase from Leishmania major.

    Science.gov (United States)

    Bose, Moumita; Saha, Rina; Sen Santara, Sumit; Mukherjee, Supratim; Roy, Jayasree; Adak, Subrata

    2012-11-15

    Heme proteins share the ability to detoxify reactive nitrogen intermediates (NO and peroxynitrite). But, to date, no heme-containing enzymatic defense against toxic reactive nitrogen intermediates has been discovered in Leishmania species. We have cloned, expressed, and characterized a pseudoperoxidase from Leishmania major (LmPP) that is capable of detoxifying peroxynitrite (ONOO(-)). Optical, EPR, and resonance Raman spectral studies demonstrate that ONOO(-) can rapidly convert the six-coordinate ferric low-spin to a ferric high-spin form at neutral pH. Western blotting and immunofluorescence studies with anti-LmPP antibody show that the mature enzyme is located at the plasma membrane of amastigotes and is expressed eightfold higher in amastigotes compared to promastigotes. Moreover, to further investigate its exact physiological role in Leishmania, we have created LmPP-knockout mutants by gene replacement in L. major strains. IC(50) values for exogenously added H(2)O(2) or 3-morpholinosydnonimine (SIN1) show that deletion of LmPP in L. major renders the cell more susceptible to SIN1. The null mutant cells exhibit a marked decrease in virulence on infection with activated macrophages as well as inoculation into BALB/c mice. Collectively, these data provide strong evidence that LmPP plays an important role in the enzymatic defense against ONOO(-) within macrophages. PMID:22985938

  12. Passive transfer of leishmania lipopolysaccharide confers parasite survival in macrophages

    International Nuclear Information System (INIS)

    Infection of macrophages by the intracellular protozoan parasite Leishmania involves specific attachment to the host membrane, followed by phagocytosis and intracellular survival and growth. Two parasite molecules have been implicated in the attachment event: Leishmania lipopolysaccharide (L-LPS) and a glycoprotein (gp63). This study was designed to clarify the role of L-LPS in infection and the stage in the process of infection at which it operates. The authors have recently identified a Leishmania major strain (LRC-L119) which lacks the L-LPS molecule and is not infective for hamsters or mice. This parasite was isolated from a gerbil in Kenya and was identified phenotypically as L. major by isoenzyme and fatty acid analysis. In this study they have confirmed at the genotype level that LRC-L119 is L. major by analyzing and comparing the organization of cloned DNA sequences in the genome of different strains of L. major. Here they show that LRC-L119 promastigotes are phagocytosed rapidly by macrophages in vitro, but in contrast to virulent strains of L. major, they are then killed over a period of 18 hr. In addition, they show that transfer of purified L-LPS from a virulent clone of L. major (V121) into LRC-L119 promastigotes confers on them the ability to survive in macrophages in vitro

  13. A unique, highly conserved secretory invertase is differentially expressed by promastigote developmental forms of all species of the human pathogen, Leishmania.

    Science.gov (United States)

    Lyda, Todd A; Joshi, Manju B; Andersen, John F; Kelada, Andrew Y; Owings, Joshua P; Bates, Paul A; Dwyer, Dennis M

    2015-06-01

    Leishmania are protozoan pathogens of humans that exist as extracellular promastigotes in the gut of their sand fly vectors and as obligate intracellular amastigotes within phagolysosomes of infected macrophages. Between infectious blood meal feeds, sand flies take plant juice meals that contain sucrose and store these sugars in their crop. Such sugars are regurgitated into the sand fly anterior midgut where they impact the developing promastigote parasite population. In this report we showed that promastigotes of all Leishmania species secreted an invertase/sucrase enzyme during their growth in vitro. In contrast, neither L. donovani nor L. mexicana amastigotes possessed any detectable invertase activity. Importantly, no released/secreted invertase activity was detected in culture supernatants from either Trypanosoma brucei or Trypanosoma cruzi. Using HPLC, the L. donovani secretory invertase was isolated and subjected to amino acid sequencing. Subsequently, we used a molecular approach to identify the LdINV and LmexINV genes encoding the ~72 kDa invertases produced by these organisms. Interestingly, we identified high fidelity LdINV-like homologs in the genomes of all Leishmania sp. but none were present in either T. brucei or T. cruzi. Northern blot and RT-PCR analyses showed that these genes were developmentally/differentially expressed in promastigotes but not amastigotes of these parasites. Homologous transfection studies demonstrated that these genes in fact encoded the functional secretory invertases produced by these parasites. Cumulatively, our results suggest that these secretory enzymes play critical roles in the survival/growth/development and transmission of all Leishmania parasites within their sand fly vector hosts. PMID:25763714

  14. T-cell responses associated with resistance to Leishmania infection in individuals from endemic areas for Leishmania (Viannia braziliensis

    Directory of Open Access Journals (Sweden)

    Rita C Bittar

    2007-08-01

    Full Text Available Subclinical or asymptomatic infection is documented in individuals living in endemic areas for leishmaniasis suggesting that the development of an appropriate immune response can control parasite replication and maintain tissue integrity. A low morbidity indicates that intrinsic factors could favor resistance to Leishmania infection. Herein, leishmanial T-cell responses induced in subjects with low susceptibility to leishmaniasis as asymptomatic subjects were compared to those observed in cured cutaneous leishmaniasis (CCL patients, who controlled the disease after antimonial therapy. All of them have shown maintenance of specific long-term immune responses characterized by expansion of higher proportions of CD4+ as compared to CD8+ Leishmania reactive T-lymphocytes. Asymptomatic subjects had lower indexes of in vitro Leishmania induced lymphoproliferative responses and interferon-gamma (IFN-gamma production in comparison to CCL patients. On the other hand, interleukin (IL-10 production was much higher in asymptomatics than in CCL, while no differences in IL-5 levels were found. In conclusion, long lived T-cell responses achieved by asymptomatic individuals differed from those who had developed symptomatic leishmaniasis in terms of intensity of lymphocyte activation (proliferation or IFN-gamma and regulatory mechanisms (IL-10. The absence of the disease in asymptomatics could be explained by their intrinsic ability to create a balance between immunoregulatory (IL-10 and effector cytokines (IFN-gamma, leading to parasite destruction without producing skin tissue damage. The establishment of profiles of cell-mediated immune responses associated with resistance against Leishmania infection is likely to make new inroads into understanding the long-lived immune protection against the disease.

  15. Myd88-Dependent In Vivo Maturation of Splenic Dendritic Cells Induced by Leishmania donovani and Other Leishmania Species

    OpenAIRE

    de Trez, Carl; Brait, Maryse; Leo, Oberdan; Aebischer, Tony; Torrentera, Fabiola Aguilar; Carlier, Yves; Muraille, Eric

    2004-01-01

    The usual agent of visceral leishmaniasis in the Old World is Leishmania donovani, which typically produces systemic diseases in humans and mice. L. donovani has developed efficient strategies to infect and persist in macrophages from spleen and liver. Dendritic cells (DC) are sentinels of the immune system. Following recognition of evolutionary conserved microbial products, DC undergo a maturation process and activate antigen-specific naïve T cells. In the present report we provide new insi...

  16. Sandfly saliva of Lutzomyia ovallesi (Diptera: Psychodidae as a possible marker for the transmission of Leishmania in Venezuela Andes region

    Directory of Open Access Journals (Sweden)

    E. Nieves , Y. Sánchez , H. Sánchez , M. Rondón, N. González & J. Carrero

    2012-03-01

    Full Text Available Background & objectives: The saliva of the Phlebotominae is highly immunogenic to the vertebrate host and isa determining factor in the Leishmania infection. The aim of this work was to study the saliva of Lutzomyiaovallesi as a possible risk marker for the transmission of Leishmania.Methods: Two populations of L. ovallesi from different geographical areas and subjected to different environmentalconditions were compared by geometric morphometry of the wings, by protein profile analysis of salivary glandsand by assessing the presence of anti-saliva protein in human sera confronted with laboratory L. ovallesi saliva.Results: The results showed differences in the isometric size and structure of the wings but no allometric effects.Protein profiles of salivary glands of both the L. ovallesi populations studied were found to be similar, based on11 protein bands with molecular weights ranging from 16 to 99 kDa. Anti-saliva antibodies were present inhuman sera, but human sera infected and uninfected with leishmaniasis could not be differentiated.Interpretation & conclusion: We conclude that the saliva of laboratory-reared L. ovallesi is representative ofthat of the wild population. It is suggested to study the presence of anti-saliva antibodies in other species ofsandflies and mosquitoes

  17. An Alba-domain protein contributes to the stage-regulated stability of amastin transcripts in Leishmania.

    Science.gov (United States)

    Dupé, Aurélien; Dumas, Carole; Papadopoulou, Barbara

    2014-02-01

    Leishmania infantum promastigotes differentiate into amastigote forms within the phagolysosome of mammalian macrophages causing visceral leishmaniasis. Delta-amastins belong to a multigenic surface protein family of potential virulence factors that are specifically expressed in the amastigote life cycle stage through distinct regulatory elements in the 3' UTR controlling either mRNA stability or translation. Here, we provide novel insights on trans-acting factors regulating amastin developmental gene expression. Using RNA affinity chromatography with a 300?nt regulatory region within the amastin 3' UTR as bait, we identified an Alba-domain protein of 25?kDa (LiAlba20) as a specific amastin mRNA-binding partner. Genomic depletion of LiAlba20 results in amastin mRNA destabilization specifically in amastigotes, supporting a role of LiAlba20 in amastin gene regulation. As shown by comparative DNA microarray analysis, several delta-amastin transcripts but also other known developmentally regulated transcripts were downregulated in LiAlba20-/- knockout parasites. Inactivation of the second Alba-domain gene, LiAlba13, does not seem to affect amastin mRNA stability in either life stage of the parasite. These data indicate an important role of Alba-domain proteins in the regulation of Leishmania differentially expressed transcripts and open a new field of investigation for better understanding mechanisms contributing to post-transcriptional control in these parasites. PMID:24620725

  18. Effects of some insecticides on the neutral lipid percentage, survival and infectivity of Steinernema carpocapsae ALL and Heterorhabditis amazonensis JPM 4

    Directory of Open Access Journals (Sweden)

    Paulo Henrique de Siqueira Sabino

    2014-08-01

    Full Text Available Lipids are an important energy source for entomopathogenic nematodes (EPNs and directly influence their infectivity in the host. Some insecticides reduce the infectivity of infective juveniles (IJs while keeping them viable after exposure. Thus, the objective of this study was to correlate the amounts of lipid reserves in the EPN Heterorhabditis amazonensis JPM 4 and Steinernema carpocapsae ALL with their survival and infectivity when exposed to insecticides that keep the nematodes viable but reduced their infective capacity against Galleria mellonella. Among the tested insecticides, Vertimec? and Klorpan? were incompatible (class 2 with the two EPN species because they reduced infectivity. The insecticides Vertimec? and Klorpan? maintained the viability of the IJs but reduced their infectivity and their lipid amounts after insecticide exposure.

  19. Canine Leishmania vaccines: still a long way to go.

    Science.gov (United States)

    Gradoni, Luigi

    2015-02-28

    Dogs are the main reservoir host for zoonotic visceral leishmaniasis, a sand fly-borne disease caused by Leishmania infantum. In endemic areas, "susceptible" dogs suffer from a severe disease characterized by chronic polymorphic viscerocutaneous signs that manifest several months from the exposure, whereas "resistant" dogs can remain subclinically infected for years or lifelong. The protective immune response to Leishmania is cell-mediated; for visceralizing Leishmania species a mixed T helper (Th)1/Th2 response with a dominant Th1 profile is required for protection. The activation of the adaptive immune system in naturally resistant dogs is revealed by parasite-specific lymphoproliferation, delayed-type hypersensitivity, the production of interferon-? and tumour necrosis factor-? cytokines, and enhanced macrophage leishmanicidal activity via nitric oxide. Hence, an effective canine Leishmania vaccine should induce strong and long-lasting Th1-dominated immunity to control both infection progression and the parasite transmissibility via the vector. Preclinical research in rodent models has evaluated the efficacy of several categories of Leishmania antigens including killed parasites, cell purified fractions, parasite protein components or subunits, single or multiple chimeric recombinant proteins, plasmid DNA and viral particles encoding parasite virulence factors. Promising antigen(s)/adjuvant combinations from each of the above categories have also been tested in dogs; they mostly resulted in limited or no protection in Phase I-II studies (designed to test vaccine safety, immunogenicity and laboratory-induced protection) in which vaccinated dogs were challenged by the artificial intravenous injection of high-load L. infantum promastigotes. The recombinant A2 antigen plus saponin conferred about 40% protection against infection by this challenge system and has been registered in Brazil as a canine vaccine (LeishTec(®)). An increasing number of efficacy studies have privileged the use of natural challenge consisting in the long-term exposure of vaccinated dogs in endemic settings (Phase III). A 2-year field model including regular assessments by a set of standard diagnostic markers useful for an accurate infection staging has been developed. Again, most of the vaccines tested by this system, which included several antigen categories and adjuvants, failed to protect against infection and disease. Only two vaccines, consisting of parasite purified fractions with saponin derivative adjuvants, showed to confer significant protection against disease and death under natural conditions, and have been registered as canine vaccines: FML-QuilA (Leishmune(®)) in Brazil, and LiESP/QA-21 (CaniLeish(®)) in Europe. PMID:25620293

  20. Leishmania isoenzyme polymorphisms in Ecuador: Relationships with geographic distribution and clinical presentation

    OpenAIRE

    Mimori Tatsuyuki; Barroso Paola A; Korenaga Masataka; Gomez Eduardo A; Kato Hirotomo; Uezato Hiroshi; Marco Jorge D; Armijos Rodrigo X.; Calvopina Manuel; Cooper Philip J.; Nonaka Shigeo; Hashiguchi Yoshihisa

    2006-01-01

    Abstract Background Determinants of the clinical presentation of the leishmaniases are poorly understood but Leishmania species and strain differences are important. To examine the relationship between clinical presentation, species and isoenzyme polymorphisms, 56 Leishmania isolates from distinct presentations of American tegumentary leishmaniasis (ATL) from Ecuador were analyzed. Methods Isolates were characterized by multilocus enzyme electrophoresis for polymorphisms of 11 isoenzymes. Pat...

  1. Biodistribution of meglumine antimoniate in healthy and Leishmania (Leishmania) infantum chagasi-infected BALB/c mice

    Scientific Electronic Library Online (English)

    Samanta Etel Treiger, Borborema; João Alberto, Osso Junior; Heitor Franco de, Andrade Junior; Nanci do, Nascimento.

    2013-08-01

    Full Text Available Pentavalent antimonials such as meglumine antimoniate (MA) are the primary treatments for leishmaniasis, a complex disease caused by protozoan parasites of the genus Leishmania . Despite over 70 years of clinical use, their mechanisms of action, toxicity and pharmacokinetics have not been fully eluc [...] idated. Radiotracer studies performed on animals have the potential to play a major role in pharmaceutical development. The aims of this study were to prepare an antimony radiotracer by neutron irradiation of MA and to determine the biodistribution of MA in healthy and Leishmania (Leishmania) infantum chagasi-infected mice. MA (Glucantime(r)) was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes, 122Sb and 124Sb, with high radionuclidic purity and good specific activity. This irradiated compound presented anti-leishmanial activity similar to that of non-irradiated MA in both in vitro and in vivo evaluations. In the biodistribution studies, healthy mice showed higher uptake of antimony in the liver than infected mice and elimination occurred primarily through biliary excretion, with a small proportion of the drug excreted by the kidneys. The serum kinetic curve was bi-exponential, with two compartments: the central compartment and another compartment associated with drug excretion. Radiotracers, which can be easily produced by neutron irradiation, were demonstrated to be an interesting tool for answering several questions regarding antimonial pharmacokinetics and chemotherapy.

  2. Leishmanicidal galloylquinic acids are noncompetitive inhibitors of arginase

    Scientific Electronic Library Online (English)

    Lorena R. F. de, Sousa; Suelem D., Ramalho; João B., Fernandes; Maria Fátima das G. F. da, Silva; Mônica R. da C., Iemma; Caroindes J., Corrêa; Dulce H. F. de, Souza; Maria I. S., Lima; Paulo C., Vieira.

    1832-18-01

    Full Text Available Ácidos galoilquínicos, substâncias que têm apresentado atividade leishmanicida, foram isolados do extrato de acetato de etila da planta Byrsonima coccolobifolia. Estes compostos fenólicos juntamente com o ácido gálico demonstraram ser uma nova classe de inibidores não-competitivos potentes em argina [...] se (ARG) de Leishmania amazonensis (Ki variando de 0,10 a 0,68 µmol L-1). O ácido quínico não apresentou atividade inibitória significativa em ARG demonstrando que a unidade galoila tem características importantes que permitem a interação enzima-inibidor. A atividade inibitória significativa do ácido gálico frente à ARG pode ser uma indicação para o entendimento da resposta imune previamente observada em Leishmania donovani, uma vez que a atividade enzimática da arginase está associada à diminuição dos níveis de NO no processo de infecção por Leishmania. Abstract in english Leishmanicidal galloylquinic acids were isolated from the ethyl acetate extract of Byrsonima coccolobifolia. These phenols and gallic acid showed to be a new class of potent noncompetitive inhibitors of arginase ARG (Ki ranging from 0.10 to 0.68 µmol L-1) from Leishmania amazonensis. Quinic acid did [...] not exhibit significant inhibition of ARG, indicating that galloyl moiety has important features that allows the enzyme-inhibitor interactions. The significant inhibitory activity of gallic acid on ARG can be a clue to understand the immune response previously observed on L. donovani, since ARG activity is associated with the decrease of the levels of NO in Leishmania infection.

  3. Clinical manifestations and genetic variation of Leishmania infantum and Leishmania tropica in Southern Turkey.

    Science.gov (United States)

    Eroglu, Fadime; Koltas, Ismail S; Alabaz, Derya; Uzun, Soner; Karakas, Mehmet

    2015-07-01

    L.?infantum was isolated from cutaneous leishmaniasis (CL) skin lesions in patients having no signs and symptoms of visceral leishmaniasis (VL). Similarly, L.?tropica had previously been isolated from patients with VL in the absence of cutaneous lesions. It was not certain how visceralization occurred. Smears (207) and bone marrow samples (135) were taken from CL and VL-suspected patients, respectively. Microscopic examination, ITS1-PCR, RFLP and DNA sequencing for all samples were analyzed. The microscopic examination of smears was found to be 61.3% (127/207) in CL-suspected cases and bone marrow samples were found to be positive 8.8% (12/135) in VL-suspected cases. L.?tropica 48.6% (72/148), L.?infantum 35.8% (53/148), L.?major 15.6% (23/148) in CL, and L.?infantum 56.3% (18/32), L.?donovani 31.2% (10/32), L.?tropica 12.5% (4/32) in VL were found with PCR-RFLP. In addition, the DNA sequencing revealed a genetic variation in L.?infantum (variants 1-3) and L.?tropica (variants 1-5). We assume that the increased disease occurrence may have resulted from geographical expansion of disease, changing patterns of international travel, population migrations, non-immune people into endemic regions of infected people into non-endemic regions. In this study, L.?infantum (variant 3) only in CL-patients and L. tropica (variant 2) only in VL-patients were identified. We hypothesize that genetic variation might play a role in the causation of CL and VL in southern Turkey and the genetic variants may differ according to the geographical location among Leishmania strains. PMID:25913665

  4. Xenodiagnostico con Lutzomyia youngi en casos venezolanos de leishmaniasis cutaned por Leishmania braziliensis Xenodiagnosis with Lutzomyia youngi in Venezuelan cases of cutaneous leishmaniais due to Leishmania braziliensis

    OpenAIRE

    Elina Rojas; Jose V. Scorja

    1989-01-01

    Xenodiagnósticos con Lutzomya yungi aplicados en los bordes de las úlceras de pacientes infectados con Leishmania braziliensis antes y después del tratamiento con 10 dosis de antimonial pentavalente y un aminoglicósido, evidencian la condición reservoria de leishmanias del enfermo, para flebótomos endofágicos y la utilidad de un tratamiento específico-temprano que no solamente conduce a la curación clínica, sino a la eliminación del riesgo de una eventual transmisión intradomiciliar por insec...