Made available in DSpace on 2015-07-13T12:10:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-03. Added 1 bitstream(s) on 2015-07-13T12:25:14Z : No. of bitstreams: 1 000835544.pdf: 2267708 bytes, checksum: f2c7c302de53b251d3e5440b6bc98d9c (MD5) / O objetivo deste trabalho foi realizar um estudo descritivo sobre o perfil das células granulocíticas e monocíticas na mucosa intestinal de cães naturalmente infectados por Leishmania infantum, na presença ou na ausência do parasita no intestino. Além disso, realizou-se um estudo de correlação entre a intensidade parasitária e os fatores clínicos do hospedeiro, as células envolvidas e as alterações histopatológicas da parede intestinal. Dos 39 cães avaliados, somente 20 foram utilizados no estudo, sendo, 17 positivos para leishmaniose visceral canina (LVC) e três negativos. Os animais com LVC foram eutanasiados no Centro de Controle de Zoonoses (CCZ) de Ilha Solteira, SP, Brasil, e os negativos vieram a óbito natural por motivos diversos. As técnicas de histoquímica e imunoistoquímica foram utilizadas para marcar as células estudadas, identificar as amastigotas de Leishmania e auxiliar nas análises histopatológicas do trato intestinal. Os cães foram divididos em três grupos (G1, G2 e G3). Oito cães positivos para LVC e com amastigotas de L. infantum no intestino foram selecionados para o grupo G1; nove cães positivos para LVC sem amastigotas intestinais para o grupo G2 e, três cães negativos compuseram o grupo controle (G3). Todos os animais não apresentaram coinfecção parasitária gastrintestinal, mediante exames coproparasitológicos realizados in vivo ou pos-morten. As variáveis clínicas dos animais, a intensidade parasitária e a presença das células mononucleares (linfócitos T CD4+, CD8+ e macrófagos) foram avaliadas por uma classificação semiquantitativa baseada em escores que variaram de 1 a 4. Já as células granulocíticas (neutrófilos, eosinófilos e mastócitos) foram quantificadas na mucosa (unidade de vilo e cripta - UVC), submucosa e na muscular. Para as análises de comparação entre os grupos (G1, G2 e G3), o teste de KrusKal-Wallis foi empregado... / The aim of this study was a descriptive evaluation on the profile of granulocytic and monocytes cells in the intestines of dogs naturally infected by Leishmania infantum in the presence or absence of the parasite in the intestine. In addition, it was performed a correlation study among parasite intensity, clinical factors of the host, the cells and the histopathological changes of the intestinal wall. 39 dogs were evaluated, but only 20 were used in the studies, 17 positive for canine visceral leishmaniasis (CVL) and three negative. The animals with CVL were euthanized in the Zoonosis Control Center (CCZ) of Ilha Solteira, SP, Brazil, and the negative animals had natural death for several reasons. The histochemical and immunohistochemical techniques were used to stain the cells and Leishmania amastigotes, and to proceed the histopathological analysis of the intestinal tract. The dogs were divided into three groups (G1, G2 and G3). Eight dogs positive for CVL and with amastigotes of L. infantum in the gut was selected to G1 group; nine CVL positive dogs without intestinal amastigotes were in G2 group and three negative dogs in the control group (G3). All animals showed no gastrointestinal parasite co- infection by coproparasitological examinations in vivo or post-mortem. Clinical variables of the animals, the parasite intensity, the presence of monocytic cells (CD4 + and CD8 + T lymphocytes and macrophages) were evaluated by a semiquantitative analysis based on scores ranging from 1 to 4. However, granulocytic cells (neutrophils, eosinophils, and mast cells) was quantified in the mucosa (villus and crypt unit - UVC), submucosa and muscle. For comparison analysis between groups (G1, G2 and G3), the Kruskal-Wallis test was used to evaluate the clinical variables, the t test for granulocytic cells, and Duncan's test to compare the monocytic cells. Correlation analyzes were based on Spearman test ...

Made available in DSpace on 2015-01-26T13:21:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-27Bitstream added on 2015-01-26T13:30:40Z : No. of bitstreams: 1 000793388.pdf: 1066055 bytes, checksum: 044f31f69403fcf74fb56af93e6c86b7 (MD5) / A leishmaniose visceral americana, causada pelo parasita intracelular Leishmania (L) infantum chagasi, é transmitida pela picada do mosquito Lutzomyia longipalpis. O tratamento é realizado à base de quimioterápicos clássicos, que desenvolvem importantes efeitos colaterais no hospedeiro. A prospecção de novas drogas é o grande desafio mundial do momento. Assim, este estudo realizado in vitro teve por objetivos avaliar o efeito anti-leishmania de frações do veneno de Crotalus durissus terrificus sobre as formas promastigotas e amastigotas de Leishmania (L) infantum chagasi. Do veneno total foram extraídas e purificadas duas frações denominadas respectivamente de fosfolipase A2 (PLA2) e peptídica. Além disso, formas promastigotas e macrófagos infectados por amastigotas foram expostos a uma diluição seriada de PLA2 e da fração peptídica em intervalos que variaram entre 1,5625 μg/mL e 200 μg/mL. Ambas demonstraram atividade contra as formas promastigotas de Leishmania (L.) infantum chagasi variando de acordo com as doses testadas e o tempo de incubação. O ensaio MTT (3- (4,5-dimetiltiazol-2yl)-2,5-difenil brometo de tetrazolina) das frações contra as formas promastigotas mostrou IC50 de 52,07 μg /mL para a PLA2, e uma IC50 de 16,98 μg/mL para a fração peptídica. O ensaio MTT para se avaliar a citotoxicidade nos macrófagos peritoneais mostrou uma IC50 de 98 μg/mL para PLA2 e uma IC50 16,98 μg/mL para a fração peptídica. Nos macrófagos peritoneais infectados pelas formas amastigotas de Leishmania (L) infantum chagasi a PLA2 estimulou o crescimento dos parasitas; em doses mais elevadas foi capaz de controlar em 23% o seu crescimento. A fração peptídica controlou 43% do crescimento do parasita intracelular na dose de 16,98 μg/mL., mostrando-se tóxica acima desta doe para os macrófagos. Ambas as frações estimularam a produção de H2O2 pelos macrófagos, mas apenas PLA2 foi capaz de estimular a produção ... / American visceral leishmaniasis is caused by the intracellular parasite Leishmania ( L ) infantum chagasi , and transmitted by sand fly Lutzomyia longipalpis. Treatment is based on classical chemotherapeutics with significant side effects and the search for new drugs is the greatest global challenge. Thus , this in vitro study aimed to evaluate the anti - leishmanicidal effect of Crotalus durissus terrificus venom’s fractions on promastigotes and amastigotes of Leishmania (L) infantum chagasi. The whole venom were purified two fractions called respectively phospholipase A2 (PLA2) and peptide. Furthermore, promastigotes and macrophage infected per amastigotes were exposed to serial dilutions of the peptide fraction and PLA2 at intervals varying between 1.5625 μg/mL and 200 μg/mL. Both showed activity against promastigotes and varies according to the tested doses and the time of incubation. The MTT assay (3-(4,5-Dimethyl-1,3- thiazol-2-yl)-3,5-diphenyl-2H-tetrazol-3-ium bromide) against promastigotes showed IC50 of 52.07 μg/mL to PLA2, and 16.98 μg/mL for peptide venom’s fraction. The MTT assay to evaluate the cytotoxicity in peritoneal macrophages showed an IC50 of 98 μg/mL for PLA2 and 16.98 μg/ml for peptide. In peritoneal macrophages infected by Leishmania (L) infantum chagasi amastigotes the PLA2 stimulated growth of parasites, at higher doses was able to control 23 % growth. The peptide fraction controlled 43 % of the intracellular parasite growth at a dose of 16.98 μg/mL, showing up this dose toxic to macrophages . Both fractions stimulated H2O2 production by macrophages but only PLA2 was able to stimulate NO production . The results encourage further studies to describe the metabolic pathways involved in cell death , as well as the prospect of molecules with antiparasitic activity present in the peptide fraction of Crotalus durissus terrificus

Made available in DSpace on 2014-06-11T19:23:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-12-18Bitstream added on 2014-06-13T18:50:07Z : No. of bitstreams: 1 000754644.pdf: 3573059 bytes, checksum: 23125aff6588402fafc80234890dc262 (MD5) / As leishmanioses são um grupo de doenças parasitárias estendidas a nível mundial e representam uma grande variedade de manifestações clínicas que vão desde leishmaniose visceral que é a forma mais grave da doença e com letalidade próxima aos 100% sem tratamento, e a leishmaniose cutânea que é de evolução usualmente benigna. As diferentes formas clínicas dependem da espécie de Leishmania que produz a doença e da resposta imune que estabelece cada hospedeiro. A lectina ligante de manose (MBL), é uma proteína que potencialmente desempenha um papel na infecção podendo levar a doença, já que ela é capaz de facilitar a infecção, promovendo a fagocitose desses parasitos intracelulares. Mutações no exon 1 e no promotor do gene da MBL humana resultam em níveis séricos baixos da proteína, o que pode proteger contra o desenvolvimento da doença. O presente estudo avaliou o papel da MBL em cães infectados com leishmaniose visceral (LVC), no Brasil, na população de Teresina – PI. (cidade endêmica para leishmaniose visceral). A procura de polimorfismos foi realizada na região promotora do gene que codifica a mbl canina, (mbl A). O DNA usado foi extraído de amostras de medula óssea de cães infectados provenientes da região. Foram encontradas apenas duas mutações do tipo SNPs na região promotora do gene da MBL. Os nossos resultados sugerem que a sequência do promotor de cães com a doença são bastante estáveis podendo ser usados como base numa possível comparação com cães sadios. Essas informações, juntamente com dados dos níveis séricos no plasma sanguíneo podem revelar a correlação entre a Leishmaniose visceral e a MBL / Leishmaniasis is a group of parasitic diseases extended worldwide and represent a wide variety of clinical manifestations ranging from visceral leishmaniasis - the most severe form of the disease with mortality close to 100 % without treatment , and cutaneous leishmaniasis which evolution is usually benign . The different clinical forms depend on the kind of Leishmania which produces the disease and the immune response that establishes each host. The mannose binding lectin (MBL) is a protein that plays a potential role on how the infection may lead to disease, because it is capable of facilitating infection by promoting phagocytosis of these intracellular parasites . Mutations in exon 1 and the promoter of the gene for human MBL result in low serum levels of the protein, which can protect against the development of disease. The present study evaluated the role of MBL in dogs infected with visceral leishmaniasis ( VL), in Brazil, in the population of Teresina - PI . (city with visceral leishmaniasis endemic) . It was looked for polymorphisms in the promoter region of the MBL gene encoding the canine (MBL A). The DNA used was extracted from bone marrow samples from dogs infected from that region. We found only two mutations for SNPs in the promoter region of the MBL gene . Our results suggest that the promoter sequence of dogs with the disease are very stable and can be used as the basis of comparison with healthy dogs . This information, together with data of serum blood plasma can reveal the correlation between the Leishmaniasis visceral and MBL

Made available in DSpace on 2014-06-11T19:23:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-06-25Bitstream added on 2014-06-13T19:50:59Z : No. of bitstreams: 1 soares_mjv_me_jabo.pdf: 1304188 bytes, checksum: 544b5360dfa9669aa67bc62df0ffaa9a (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O cão é um importante reservatório do agente etiológico da leishmaniose visceral (LV). Este estudo compreendeu a avaliação de aspectos clínico-laboratoriais, histopatologia renal (cap. 2) e uso da PCR na identificação do agente infectante em baço, fígado, linfonodo e rins em cães com LV (cap. 3). No primeiro estudo, foram utilizados 34 cães soropositivos sintomáticos (caso), e 17 assintomáticos (controle), machos ou fêmeas, com raças e idades variadas, provenientes de Teresina-PI. Os cães foram submetidos a eutanásia. Após, foram coletados fragmentos de baço, fígado, linfonodo e rins. Fragmentos renais foram preparados por técnicas histológicas e corados com HE e PAS. Ao exame físico, foi freqüente hipertrofia de linfonodos (85,29%) e úlceras cutâneas (35,29%) no grupo caso. Verificou-se anemia em 55,88% dos cães no grupo caso e 11,76% no controle. A avaliação histopatológica renal no grupo caso, revelou que 61,76% dos cães apresentaram glomerulonefrite (GN) membranoproliferativa e, no controle, 17,65%. GN proliferativa mesangial ocorreu em 32,35% dos cães do grupo caso e em 64,70% do controle. Foram encontradas formas amastigotas de Leishmania em meio ao infiltrado inflamatório em um dos cães do grupo caso. No segundo estudo, utilizaram-se 25 cães soropositivos para LV sintomáticos (caso) e 15 assintomáticos (controle). As PCRs foram realizadas em termociclador automático, utilizando-se primers específicos para o gênero Leishmania. Os 25 cães do grupo caso, foram positivos nas PCRs de baço, ou fígado ou linfonodo, contra dois cães do grupo controle. Por meio das PCRs em rins, detectou-se DNA de Leishmania em oito animais (32%) do grupo caso. O estudo permitiu concluir que na LV canina, independentemente de haver sinais detectados ao exame físico, os rins freqüentemente estão acometidos e que a PCR é um exame mais preciso que a histopatologia convencional, na detecção da presença do parasita. / The dog is an important reservoir of visceral leishmaniasis (VL) etiological agent. This study included clinical and laboratorial evaluation, renal histopathology (chapter 2) and the use of PCR in the identification of the infective agent on the spleen, liver, lynphonodes and kidney in dogs with VL (chapter 3). In the first study, it were used 34 symptomatic soropositives dogs (case), and 17 asymptomatic (control), male or female, with different breeds and ages, coming from Teresina-PI. The dogs were submitted to euthanasia. Right after, samples from spleen, liver, lymphonodes and kidneys were collected. Renal fragments were prepared using histological techniques and stained with HE and PAS. At physical exam, it was frequent lymphonodes hypertrophy (85.29%) and cutaneous ulcers (35,29%) in the case group. Anaemia was presented in 55.88% of the dogs from case group and 11.76% from control. The renal histopathology evaluation of the case group showed that 61.76% of the dogs presented membranoproliferative glomerulonephritis (GN) and, at the control group, 17.65%. Mesangial proliferative glomerulonephritis occurred in 32.35% of the dogs from case group and in 64.70% from control. In one of the dogs from case group, it was found amastigotes forms of Leishmania in the middle of the inflamatory infiltrated. In the second study, it were used 25 symptomatics soropositives dogs for VL (case) and 15 asymptomatic (control). PCRs were accomplished at an automatic termocycler using specific primers for Leishmania. All 25 dogs from case group were positives in PCRs of spleen, or liver or lymphonode, and only two from the control group. Through the PCRs of the kidneys, it was detected DNA of Leishmania in eight animals (32%) from case group... (complete abstract, access undermentioned eletronic address)

Submitted by ERIC MATEUS NASCIMENTO DE PAULA null (eric.gyn@gmail.com) on 2016-07-30T15:23:11Z No. of bitstreams: 1 DISTRIBUIÇÃO ESPACIAL DA LEISHMANIOSE VISCERAL NO ESTADO DE SÃO PAULO, BRASIL, NO PERÍODO DE 1970 A 2014 Eric Mateus Nascimento de Paula.pdf: 3717410 bytes, checksum: 71497894de34d4d26508834cfadfd11a (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-08-02T13:37:45Z (GMT) No. of bitstreams: 1 paula_emn_me_jabo.pdf: 3717410 bytes, checksum: 71497894de34d4d26508834cfadfd11a (MD5) / Made available in DSpace on 2016-08-02T13:37:45Z (GMT). No. of bitstreams: 1 paula_emn_me_jabo.pdf: 3717410 bytes, checksum: 71497894de34d4d26508834cfadfd11a (MD5) Previous issue date: 2016-04-14 / Atualmente, no Brasil, a leishmaniose visceral (LV) é classificada como uma enfermidade reemergente, em processo de transição epidemiológica, juntamente com um aumento da incidência nas áreas endêmicas e presente em quatro das cinco regiões do território nacional. Assim, este trabalho objetiva analisar a evolução e a distribuição espacial da LV no Estado de São Paulo, desde o seu primeiro registro até o ano 2014, com vistas a fornecer subsídios para as autoridades de saúde pública para melhoria do programa de controle. Por meio de um estudo descritivo, dados secundários obtidos junto ao Centro de Vigilância Epidemiológica (CVE) e à Superintendência de Controle de Endemias (SUCEN) do Estado de São Paulo foram analisados e tratados em um sistema de informações geográficas (ArcGis 10.1), com confecção de mapas de distribuição. Observou-se que existem dois padrões distintos da distribuição da LV no estado: o da região oeste, definido pela ocorrência de casos humanos, alta prevalência de casos caninos e um maior número de municípios onde L. longipalpis está presente; e o da região leste, caracterizada pela ausência de notificação de casos humanos, até mesmo onde o flebotomíneo e casos caninos são presentes. Deduz-se que a expansão ocidental dos casos caninos e humanos seguindo a mesma rota de expansão do vetor não é coincidência, isso porque os registros do flebotomíneo precedem as notificações da doença no cão e, subsequentemente, no ser humano. A pesquisa serve de base para estudos futuros e fornece subsídios para ações do Programa Estadual de Controle. Sugere-se que haja um contínuo levantamento da presença do vetor e vigilância sorológica dos cães, bem como educação da população para que esteja receptiva à eutanásia dos cães em casos positivos, uma vez que em relação ao ciclo do vetor, nada pode ser feito. / Nowadays, in Brazil, visceral leishmaniasis (VL) is classified as a re-emerging disease, in a clear process of epidemiological transition, along with an increased incidence in endemic areas, and present in four of the five regions of the country. Therefore, this essay aims to analyze the evolution and spatial distribution of VL in São Paulo, since its first record until the year 2014, in order to provide information for public health authorities to improve the control program. By means of an ecological and descriptive study, secondary data obtained from the Centro de Vigilância Epidemológica (CVE) and the Superintendência de Controle de Endemias (SUCEN) of São Paulo were analyzed and treated in a geographic information system (ArcGIS 10.1), with confection distribution maps. It was observed that there are two distinct patterns of distribution of LV in São Paulo: one in the western region, defined by the occurrence of human cases, high prevalence of canine cases and a greater number of municipalities where sand fly is present; the other, represented by the eastern region, characterized by the absence of reporting human cases, even where the sand flies and canine cases are present. It follows that western expansion of canine and human cases following the same expansion route as the vector is not a coincidence, since the phlebotomine sandflies records precede the notifications of the disease in dogs and subsequently in humans. The research is the basis for future studies and provides subsidies for actions of the State Control Program. It is suggested that there is a continuous survey of the presence vector and serological monitoring of dogs as well as education of the population so that it is receptive to euthanasia dogs in the positive cases, since in relation to the vector cycle, nothing can be done.

Orientador : Paulo Inácio da Costa / Coorientador: Márcia Aparecida Silva Graminha / Banca: Andrea Soares da Costa Fuentes / Banca: Mara Cristina Pinto / Banca: Silmara Marques Allegretti / Banca: Marco Tulio Alves da Silva / Resumo: A leishmaniose visceral canina (LVC) é a forma clínica mais severa da doença e pode ser fatal se não tratada. Um diagnóstico específico e acurado é requerido para a identificação de cães infectados a fim de promover um melhor controle epidemiológico e tratamento adequado. O desenvolvimento de um teste diagnóstico mais específico é importante, especialmente no Brasil onde os animais infectados são eutanaziados. Diversos pesquisadores discordam quanto à especificidade dos testes atualmente utilizados. Este trabalho reporta o isolamento, expressão e teste de dois genes específicos de Leishmania infantun (syn = chagasi), como potencial epítopo para desenvolvimento de um novo método diagnóstico e vacina. Os genes denominados Lc 24 e Lc 36 foram amplificados com primers específicos, clonados e expressos em E. coli. As proteínas recombinantes rLc 24 e rLc 36 foram purificadas por cromatografia de afinidade em coluna de GST. Diferentes concentrações das proteínas foram testadas por Dot Blot usando um pool de soros de cães infectados com leishmaniose visceral e um pool de soro de cães não infectados. Concentrações das proteínas a 0,1 e 0,01μg/mL foram detectadas no ensaio, mostrando que as proteínas rLc 24 e rLc 36 são imunorreativas e apresentam potencial para serem usadas em novos testes diagnósticos e desenvolvimento de vacina. / Abstract: Canine visceral leishmaniasis (CVL) is the most severe clinical form of the disease and can be fatal if untreated. A specific and accurate diagnosis is required for the identification of infected dogs to provide better epidemiological control and earlier treatment. The more accurate diagnosis test is important especially in Brazil where infected animals are euthanized. Discordance among investigators regarding the accuracy of the tests currently employed for this purpose. This works reports the isolation, expression and test of two specific genes of Leishmania infantun (syn = chagasi), as a potential epitope for the development of a new diagnosis method and vaccine. The partial sequence of the genes rLc 24 and rLc36 was amplified with specific primers, cloned, and expressed in E. coli. The rLc 24 and rLc36 recombinant proteins was purified by GST affinity chromatography. Different concentrations of proteins were tested by Dot blot using a serum pool from infected dogs with leishmaniasis and a serum pool from dogs not infected. The protein concentrations of 0,1 and 0,01μg/mL were detected in the dot blot tests, showing that the protein rLc36 is immunoreaction and has potential to used in new diagnosis tests and development of vaccine. / Doutor

Orientador: Rui Seabra Ferreira Junior / Banca: Lucilena Delazari dos Santos / Banca: Ricardo de Oliveira / Resumo: A leishmaniose visceral americana, causada pelo parasita intracelular Leishmania (L) infantum chagasi, é transmitida pela picada do mosquito Lutzomyia longipalpis. O tratamento é realizado à base de quimioterápicos clássicos, que desenvolvem importantes efeitos colaterais no hospedeiro. A prospecção de novas drogas é o grande desafio mundial do momento. Assim, este estudo realizado in vitro teve por objetivos avaliar o efeito anti-leishmania de frações do veneno de Crotalus durissus terrificus sobre as formas promastigotas e amastigotas de Leishmania (L) infantum chagasi. Do veneno total foram extraídas e purificadas duas frações denominadas respectivamente de fosfolipase A2 (PLA2) e peptídica. Além disso, formas promastigotas e macrófagos infectados por amastigotas foram expostos a uma diluição seriada de PLA2 e da fração peptídica em intervalos que variaram entre 1,5625 μg/mL e 200 μg/mL. Ambas demonstraram atividade contra as formas promastigotas de Leishmania (L.) infantum chagasi variando de acordo com as doses testadas e o tempo de incubação. O ensaio MTT (3- (4,5-dimetiltiazol-2yl)-2,5-difenil brometo de tetrazolina) das frações contra as formas promastigotas mostrou IC50 de 52,07 μg /mL para a PLA2, e uma IC50 de 16,98 μg/mL para a fração peptídica. O ensaio MTT para se avaliar a citotoxicidade nos macrófagos peritoneais mostrou uma IC50 de 98 μg/mL para PLA2 e uma IC50 16,98 μg/mL para a fração peptídica. Nos macrófagos peritoneais infectados pelas formas amastigotas de Leishmania (L) infantum chagasi a PLA2 estimulou o crescimento dos parasitas; em doses mais elevadas foi capaz de controlar em 23% o seu crescimento. A fração peptídica controlou 43% do crescimento do parasita intracelular na dose de 16,98 μg/mL., mostrando-se tóxica acima desta doe para os macrófagos. Ambas as frações estimularam a produção de H2O2 pelos macrófagos, mas apenas PLA2 foi capaz de estimular a produção ... / Abstract: American visceral leishmaniasis is caused by the intracellular parasite Leishmania ( L ) infantum chagasi , and transmitted by sand fly Lutzomyia longipalpis. Treatment is based on classical chemotherapeutics with significant side effects and the search for new drugs is the greatest global challenge. Thus , this in vitro study aimed to evaluate the anti - leishmanicidal effect of Crotalus durissus terrificus venom's fractions on promastigotes and amastigotes of Leishmania (L) infantum chagasi. The whole venom were purified two fractions called respectively phospholipase A2 (PLA2) and peptide. Furthermore, promastigotes and macrophage infected per amastigotes were exposed to serial dilutions of the peptide fraction and PLA2 at intervals varying between 1.5625 μg/mL and 200 μg/mL. Both showed activity against promastigotes and varies according to the tested doses and the time of incubation. The MTT assay (3-(4,5-Dimethyl-1,3- thiazol-2-yl)-3,5-diphenyl-2H-tetrazol-3-ium bromide) against promastigotes showed IC50 of 52.07 μg/mL to PLA2, and 16.98 μg/mL for peptide venom's fraction. The MTT assay to evaluate the cytotoxicity in peritoneal macrophages showed an IC50 of 98 μg/mL for PLA2 and 16.98 μg/ml for peptide. In peritoneal macrophages infected by Leishmania (L) infantum chagasi amastigotes the PLA2 stimulated growth of parasites, at higher doses was able to control 23 % growth. The peptide fraction controlled 43 % of the intracellular parasite growth at a dose of 16.98 μg/mL, showing up this dose toxic to macrophages . Both fractions stimulated H2O2 production by macrophages but only PLA2 was able to stimulate NO production . The results encourage further studies to describe the metabolic pathways involved in cell death , as well as the prospect of molecules with antiparasitic activity present in the peptide fraction of Crotalus durissus terrificus / Mestre

Orientador: Sueli Aparecida Calvi / Coorientador: Lucilene Delazari dos Santos / Resumo: A leishmaniose visceral (LV) é causada pelos protozoários intracelulares obrigatórios pertencentes ao complexo Leishamania donovani (L.donovani). O sucesso na cura da LV depende principalmente do estado imunitário do hospedeiro em combinação com os efeitos das drogas leishmanicidas. Nesse sentido, a resistência do hospedeiro a leishmaniose está associada à produção de citocinas envolvidas na indução e efetuação de uma resposta do tipo Th1, como IL-12, IFN-γ e TNF-α. Essa resposta culmina na ativação de macrófagos com conseqüente aumento na produção de metabólitos do estresse oxidativo com atividade leishmanicida. Por outro lado, a suscetibilidade à infecção e a progressão da doença estão relacionadas com o direcionamento de uma resposta do tipo Th2, com produção de IL-4 e de outras citocinas como a IL-10, que desativam macrófagos. A subpopulação de células Th17 vem ganhando importância na resposta contra a Leishmania, entretanto não se sabe até o momento se está envolvida na resistência ou suscetibilidade à infecção. Apesar desses resultados, são raros os trabalhos que tenham objetivado avaliar de forma sistemática, os perfis de resposta de células CD4+ em pacientes com LV, antes e após o tratamento. Desta forma, um dos objetivos do presente estudo foi quantificar as citocinas do perfil Th1, Th2 e Th17 nestas duas fases da evolução da doença. Outro objetivo foi avaliar o estado redox desses pacientes, uma vez que ao tentar eliminar o parasita através do processo de ativação d... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Visceral leishmaniasis (VL) is caused by obligatory intracellular protozoa belonging to Leishmania donovani (L. donovani) complex. The success in LV cure depends mainly on the immune status of the host in combination with the effects of antileishmanial drugs. Accordingly, leishmaniasis host resistance is associated with production of cytokines involved in Th1 response induction and its effector functions, such as IL-12, IFN-γ and TNF-α. This response culminates in macrophages activation, that begin to release higher levels of oxigen and nitrogen reactive species that have potent leishmanicidal activities. In contrast, susceptibility to infection and disease progression are linked to a predominat Th2 response that produces IL-4 and other cytokines such as IL-10 that deactivate macrophages. The importance of Th17 subset in host response to leishmania has also been studied, however it is not established yet if it is involved in resistance or susceptibility to infection. Despite these findings, few studies have aimed to evaluate the predominant profiles of CD4 + cells that are activated in patients with LV before and after treatment. Thus, one of the objectives of the present study was to quantify the cytokines tipical of Th1, Th2 and Th17 profiles in these two stages of disease progression. In addittion, we aimed to evaluate the redox status of these patients, since by trying to eliminate the parasite through the macrophage activation process, they can release excessive am... (Complete abstract click electronic access below) / Mestre

Visceral leishmaniasis (VL) or kala-azar is a parasitic infectious disease that is fatal if left untreated. Two types of Leishmania species are causal agents of VL: Leishmania infantum and Leishmania donovani. VL caused by L.infantum is a zoonosis and is endemic in countries around the Mediterranean basin and in Latin-America. VL caused by L. donovani is assumed to be an anthroponosis and is endemic in East-Africa and the Indian subcontinent.<p><p>VL is considered as a major public health problem in the Indian subcontinent and the annual case load of VL in this focus is represents around 80% of the global burden. In Nepal, a quarter of the country’s population is estimated to be at risk of this disease. The disease in the ISC is caused by L. donovani, which is transmitted from man to man by the bite of the sandfly Phlebotomus argentipes. VL occurs predominantly among the poorest of the poor. Since 2005, the governments of Bangladesh, India and Nepal have been engaged in a collaborative effort to eliminate VL from the region. The strategies to control the disease include early diagnosis and treatment, along with vector control measures, effective disease surveillance, social mobilization and partnership building, and clinical and operational research. In recent years, considerable efforts were made within the elimination initiative. Still, important gaps remain in the understanding of the VL epidemiology, and impact as well as on the best approach to case management or vector control. These knowledge gaps may affect the success of the ongoing VL elimination initiative and make it difficult to meet the set target of bringing the incidence down to less than 1 case per 10,000 by 2015. With this background we focused on some of the knowledge gaps; we wanted to generate evidence and offer sound recommendations for policy makers to underpin the ongoing VL elimination initiative in the Indian subcontinent in general and in Nepal in particular. <p><p>We have - for the first time- described the epidemiology of L. donovani infection in high transmission areas in Nepal. The sero-prevalence of L. donovani infection was 9% in these communities, but there was wide variation between endemic villages (5-15%). The seroprevalence rates remain however substantially lower than those observed in a parallel study in the neighbouring districts in Bihar, India. In our study 39% of individuals who live together in a house with at least one recent VL case were serologically (DAT) positive compared to 9% in the overall study population in the same endemic region. This pattern suggests that untreated VL cases are the main source of transmission and sharing the same household is an important risk factor for L. donovani infection. Therefore, the VL elimination campaign recently initiated an active case detection strategy including the search of active cases of VL and post-kala-azar dermal leishmaniasis (PKDL).<p><p>Generally the risk factors for VL are linked to precarious housing conditions and an environment that provides excellent breeding sites for the sandfly vector.VL has thus been largely considered as a disease of the rural poor. However, with occasional cases being reported also from town e.g. Dharan in south-eastern Nepal, questions were raised about possible extension of transmission to urban areas.<p><p>We conducted an outbreak investigation including a case-control study among the residents of Dharan town. We documented several clusters of VL cases in the more peripheral wards of the town. These are wards with new settlements where the poorest migrants install themselves. They are typically a rural-urban interface with most residents dependent on daily wages as agricultural labourers. However, several factors pointed to urban transmission: firstly, we found a strong association between VL and certain housing factors. Secondly, the clustering of VL cases in space and the intra-household clustering makes urban transmission more likely than infection due to migration. Finally, the entomological data also provide further evidence in support of local transmission of VL inside the town. The vector P. argentipes was captured repeatedly inside the town, and some of them were infested with L. donovani.<p><p>We studied the health seeking behavior and documented the households cost of VL care in a miltefosine-based programme after the intensified implementation of VL control efforts in Nepal. We enrolled 168 patients that had been treated for VL within twelve months prior to the survey in five districts in south-eastern Nepal. We observed a median delay of 25 days to present to the appropriate level of the primary healthcare system. Most patients first visited unqualified local practitioners or traditional faith healers for VL care. With a median total cost of US$ 165 per episode of VL treatment, the economic burden of VL across all households was 11% of annual household income or 57% of median annual per capita income. About half of the households exceeded the catastrophic expenditure threshold of 10% of annual household income. Our findings seem to suggest that, compared to previous studies, the economic burden of VL (as a % of household income) has indeed decreased. However, despite the provision of free diagnostics and drugs by the government, households still incurred substantial medical out-of-pocket expenditure, especially at private providers. The government should consider specific policies to reduce VL care costs such as a conditional cash programme for travel and food, and a better health insurance scheme. <p><p>We monitored clinical outcomes of VL treatment with miltefosine up to 12 months after the completion of therapy and explored the potential role of patient compliance, drug resistance, and reinfection. The initial cure rate was 95.8% and cure rate at 6 months after treatment was 82.5%, which further dropped to 73.3% at 12 months after miltefosine treatment. The relapse rate at 6 months was 10.8% and 20.0% at 12 months i.e. relapse is observed in one-fifth of miltefosine treated VL patients in Nepal. The decreased effectiveness of miltefosine observed in our study is an alarming signal for the ongoing VL elimination initiative and implicates the need for reviewing the drug policy in the Indian subcontinent. Relapse was most common among children (<12 years of age) and continued to occur beyond the commonly used 6-month follow-up period. No significant clinical risk factors or predictors of relapse apart from age <12 years were found. Parasite fingerprints of pre-treatment and relapse bone marrow isolates were similar within 8 tested patients, suggesting that clinical relapses were not due to re-infection with a new strain, but due to true recrudescences. MIL blood levels at the end of treatment were similar for cured and relapsed patients.The MIL-susceptibility of 131 VL isolates was also analysed in vitro with a promastigote assay and the mean promastigote MIL-susceptibility (IC50) of isolates from definite cures was similar to that of relapses.<p><p>We also assessed patient adherence to miltefosine treatment for VL given on an unsupervised ambulatory basis, prescribed under routine conditions (i.e. little or no time for treatment counselling) in government primary healthcare facilities. Our findings showed that adherence is a problem and the target of 90% of capsules taken is not reached in 15% of the enrolled patients. The gastrointestinal related side-effects and treatment-negligence after the resolution of clinical symptoms of VL were the main reasons for poor adherence. Effective counselling during the treatment, a short take-home message on the action and side effects of miltefosine, and on the importance of adherence are the best way to prevent poor adherence.<p><p>Post-kala-azar dermal leishmaniasis is more commonly seen in inadequately treated cases which is considered as a reservoir of infection maintaining disease transmission. The occurrence of PKDL in Nepal is relatively low compared to neighbouring countries involved in the elimination initiative. Supervised and adequate treatment of VL seems essential to reduce the risk of PKDL development. Policy makers should include surveillance and case management of PKDL in the VL elimination programme.<p> / Doctorat en Santé Publique / info:eu-repo/semantics/nonPublished

Visceral leishmaniasis is a severe systemic illness and early case management is important for the avoidance complications and control of the disease. Improving health workers’ knowledge on leishmaniasis is essential in improving the control programme. A quantitative, retrospective study of patient records and descriptive, explorative study of health care professionals’ knowledge on leishmaniasis were conducted. Data was collected from patient records (n=299) using a structured audit tool and from health care professionals (n=55) by means of a structured questionnaire. The study findings highlight that the commonest clinical manifestations of visceral leishmaniasis are fever and splenomegaly. Severe malnutrition and HIV co-infection contribute to mortality. The findings indicate the need for training to improve health care professionals’ awareness of visceral leishmaniasis. Leishmaniasis disease surveillance and support by the regional and district heath offices should be improved / Health Studies / M.A. Public Health (MPH)