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1.
Mem. Inst. Oswaldo Cruz ; 115: e190284, 2020. tab
Article in English | LILACS | ID: biblio-1056772

ABSTRACT

Despite some phlebotomines being well recognised as vectors of leishmaniasis agents, vector importance of those belonging to the genus Trichophoromyia has not been extensively studied. The present study provides evidence regarding the putative vector role played by some species of Trichophoromyia on leishmanine enzootics, based on literature reports and findings obtained from field experiments conducted in the ecotopes of Pará State, Brazil. The species Th. ubiquitalis, Th. velascoi, Th. auraensis, Th. ininii and Th. brachipyga possess minimal criteria to be included in the list of suspected leishmanine vectors. However, knowledge on man-biting behavior, substantiation of vector competence and determination of epidemiological implications are limited for all of the above mentioned species. Published studies together with present data draw attention to prioritize these phlebotomine species in entomological surveillance programs and studies on experimental susceptibility to Leishmania spp. infection.


Subject(s)
Animals , Psychodidae/parasitology , Insect Vectors/parasitology , Leishmania/classification , Leishmaniasis/transmission , Polymerase Chain Reaction , DNA, Protozoan/genetics , Leishmania/genetics
2.
Rev. bras. parasitol. vet ; 28(4): 574-581, Oct.-Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1057998

ABSTRACT

Abstract Leishmaniases are a group of diseases of zoonotic importance caused by over 20 species of protozoa of the genus Leishmania, in which domestic dogs are considered to be the main reservoir for the disease. However, the involvement of other vertebrates as reservoirs for these parasites has also been investigated. Therefore, the objective of the present study was to carry out a systematic review with meta-analysis on occurrences of leishmaniasis in equids. The case reports described animals with cutaneous symptoms of leishmaniasis (papules, nodules, ulcers or crusts) that regressed spontaneously, located mainly on the head and limbs, from which three species of protozoa were identified in the lesions: Leishmania braziliensis, Leishmania infantum and Leishmania siamensis. In turn, the meta-analysis showed a combined prevalence of 25%, although with high heterogeneity among the studies, which was attributed to the use of different methods for diagnosing the disease. Leishmaniasis in equids is a benign disease but it should be included in the differential diagnosis of cutaneous diseases among these species. Seroepidemiological studies are important in investigating and monitoring suspected exposure of these hosts to the parasite, especially in endemic areas. However, there is also a need to standardize diagnostic methods.


Resumo As leishmanioses são um grupo de doenças de importância zoonótica causadas por mais de 20 espécies de protozoários do gênero Leishmania, sendo o cão doméstico considerado o principal reservatório da doença. No entanto, diversas pesquisas têm investigado o envolvimento de outros vertebrados como reservatórios do parasita. Portanto, o objetivo do presente estudo foi realizar uma revisão sistemática com meta-análise da ocorrência de leishmaniose em equídeos. Os relatos de caso descreviam animais com sintomas cutâneos de leishmaniose (pápulas, nódulos, úlceras, crostas) que regrediam espontaneamente, localizadas principalmente na cabeça e membros, sendo identificadas três espécies do protozoário nas lesões: Leishmania braziliensis, Leishmania infantum e Leishmania siamensis. Por sua vez, a meta-análise evidenciou uma prevalência combinada de 25%, porém com alta heterogeneidade entre os estudos, atribuída às diferenças nos métodos utilizados no diagnóstico da doença. A leishmaniose em equídeos é uma doença benigna, porém deve ser incluída no diagnóstico diferencial de doenças cutâneas nessas espécies. Os estudos soroepidemiológicos são importantes para investigar e monitorar a suspeita de exposição desses hospedeiros ao parasita, principalmente em áreas endêmicas, porém há necessidade de padronização dos métodos de diagnóstico.


Subject(s)
Animals , Leishmaniasis/veterinary , Horse Diseases/parasitology , Horses/parasitology , Leishmania/isolation & purification , Disease Reservoirs , Leishmania/classification
3.
Rev. Soc. Bras. Med. Trop ; 51(4): 537-541, July-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-1041471

ABSTRACT

Abstract INTRODUCTION: Leishmania species cause skin, mucosal, and disseminated lesions. We studied the effects of three Leishmania species on ileal morphology in mice. METHODS: BALB/c mice were intraperitoneally inoculated with Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis, and Leishmania (Leishmania) major (4 animals/group). After 72h, the ilea were collected and histologically processed. RESULTS: Following inoculation, the goblet cell and intraepithelial lymphocyte populations increased, while Paneth cell number and crypt width decreased. In addition, enterocyte size, villi height, and mucosa, submucosa, and muscular tunic thickness increased. CONCLUSIONS: Leishmania modified the quantity of cells in and morphology of mice ilea.


Subject(s)
Animals , Female , Leishmaniasis/parasitology , Leishmaniasis/pathology , Ileum/parasitology , Ileum/pathology , Leishmania/pathogenicity , Mice , Species Specificity , Disease Models, Animal , Leishmania/classification , Mice, Inbred BALB C
4.
Pesqui. vet. bras ; 38(6): 1058-1063, jun. 2018. graf
Article in English | LILACS, VETINDEX | ID: biblio-955451

ABSTRACT

This study aimed to verify the occurrence of Leishmania spp. and Leishmania (Leishmania) infantum in horses from a visceral leishmaniasis endemic area in Brazil. DNA samples from blood and conjunctival swab (CS) were tested by PCR and Indirect Immunofluorescence Antibody Test (IFAT). Although none of the horses was clinically sick, animals infected by Leishmania spp. were found and some could be characterized as infected by L. (L.) infantum. From 40 horses, 100% of the animals were positive by blood PCR, 90% (36/40) by CS PCR, and 2.5% (01/40) in serodiagnosis, by IFAT. Six from these 40 horses were L. (L.) infantum positive by blood PCR. Direct sequencing and analysis of amplicons resulted in a sequence to evolutionary analysis. Results indicate the presence of Leishmania spp. and L. (L.) infantum infecting healthy horses in Brazil. The presence of Leishmania spp. and L. (L.) infantum DNA in asymptomatic horses suggests that they can be important reservoirs of these parasites, a highly relevant finding for the epidemiological surveillance of the diseases they cause.(AU)


O estudo objetivou verificar a ocorrência de Leishmania spp. e Leishmania (Leishmania) infantum em cavalos de uma região endêmica para leishmaniose visceral do Brasil. Amostras de DNA de sangue e suabe conjuntival (SC) foram testadas pela PCR e pela Reação de Imunofluorescência Indireta (RIFI). Embora nenhum cavalo estivesse clinicamente doente, animais infectados por Leishmania spp. e L. (L.) infantum foram encontrados em Ilha Solteira/SP. Dos 40 cavalos, 100% (40/40) foram positivos pela PCR de sangue, 90% (36/40) pela PCR de SC, e 2,5% (01/40) no sorodiagnóstico, pela RIFI. Seis desses 40 cavalos foram positivos para L. (L.) infantum pela PCR de sangue. O sequenciamento direto e a análise dos amplicons resultaram em uma sequência para análise evolutiva. Os resultados indicam a presença de Leishmania spp. e L. (L.) infantum infectando cavalos saudáveis no Brasil. A presença de DNA de Leishmania spp. and L. (L.) infantum em cavalos saudáveis sugere que eles podem ser importantes reservatórios desses parasitas, um achado altamente relevante para a vigilância epidemiológica das doenças que causam.(AU)


Subject(s)
Animals , Serologic Tests/veterinary , Leishmania infantum/immunology , Leishmania/classification
5.
São Paulo; s.n; s.n; 2018. 95 p. ilus, graf.
Thesis in Portuguese | LILACS | ID: biblio-915566

ABSTRACT

Doenças causadas por agentes infecciosos e parasitários são chamadas negligenciadas por não despertarem interesse das indústrias farmacêuticas para o desenvolvimento de novas alternativas terapêuticas. Essas doenças são responsáveis por levar milhões de pessoas à morte todos os anos e afetam principalmente os países pobres e em desenvolvimento. Dentre estas, a doença de Chagas e as leishmanioses, parasitoses causadas por parasitas flagelados pertencentes à família Trypanosomatidae, T. cruzi e Leishmaina sp., respectivamente, se apresentam como um sério problema de saúde pública mundial. Endêmicas em vários países e causando milhões de mortes anualmente, ainda hoje não existem fármacos eficientes e seguros para o tratamento dessas doenças. Este panorama torna eminente a necessidade de pesquisa e desenvolvimento de novos fármacos para essas parasitoses. A busca por agentes quimioterápicos envolve a seleção de vias metabólicas essenciais à sobrevivência dos parasitas. Dentre estas, destacamse cisteíno-proteases presentes nesses tripanossomatídeos, deste modo a cruzaína no T. cruzi, e a CPB2.8 na Leishmania mexicana, se mostram como alvos bioquímicos promissores. A disponibilidade de estruturas cristalográficas da cruzaína e do sequenciamento genômico da CPB2.8, nos permite utilizar estratégias de planejamento de fármacos baseado no receptor (SBDD) na identificação de candidatos a fármacos para essas doenças. Entre as técnicas modernas de SBDD utilizadas, a triagem virtual possibilita identificar promissores candidatos a novos fármacos. Assim neste trabalho, obteve-se por meio da técnica de modelagem comparativa o modelo da enzima CPB2.8 de L. mexicana, visto a indisponibilidade da estrutura cristalográfica no Protein Data Bank (PDB). De modo a refinar o modelo construído realizou-se a simulação por dinâmica molecular de 100ns, apresentando estabilização a partir de 80ns. A simulação por dinâmica molecular foi validada por meio do gráfico de Ramachandran, gráfico de raio de giro, RMSD, gráfico de superfície hidrofóbica. Foram calculados os mapas de interação molecular no programa GRID das seguintes proteínas: cruzaína, CPB2.8, catepsina B e catepsina L, e, posteriormente, foi construído um modelo farmacofórico baseado no sítio ativo das enzimas cruzaína e CPB2.8. O modelo farmacofórico da cruzaína foi validado por curva ROC apresentando valor de AUC 61%. A triagem virtual foi realizada para ambas as proteínas e foram obtidos 369 compostos para a cuzaína e 225 compostos para a CPB2.8. Foi realizado o ancoramento molecular desses compostos obtidos pela triagem virtual a fim de diminuir a quantidade de compostos a serem avaliados experimentalmente


Neglected diseases are caused by parasites and infectious agents and affect mainly people in poor areas being prevalent in 149 countries and causing 534,000 deaths per year. Among neglected diseases we can highlight Chagas Disease and Leishmaniasis, both have a high rate of morbidity and mortality and both are addressed in this project in the search of new drugs against a NTD. Nowadays, the search for new drugs involves the selection of biological pathways essential for parasite survival, in this class of parasites we can suggest the cysteine proteases, a proteases family present in Trypanosoma cruzi and and Leishmania ssp. In order to obtain a new agent against Neglected Disease in this work was obtained the model of the enzyme CPB2.8 of L. mexicana using the comparative modeling technique, due to the unavailability of the crystallographic structure in the Protein Data Bank (PDB). In order to refine the constructed model was performed the molecular dynamics simulation of 100ns, stabilization was achieved from 80ns. Molecular dynamics simulation was validated using the Ramachandran graph, radius of rotation graph, RMSD, hydrophobic surface area graph. The molecular interaction fields were calculated in the GRID program to cruzain, CPB2.8, cathepsin B and cathepsin L. Based on molecular interaction fields generated pharmacophoric models were constructed using information about the active site of the enzymes cruzain and CPB2.8. The pharmacophoric model of cruzain was validated by ROC curve presenting AUC value of 61%. Virtual screening was performed for both proteins and 369 compounds were obtained for cuzain and 225 compounds for CPB2.8. Docking studies of these compounds was performed in order to decrease the amount of compounds to be evaluated experimentally


Subject(s)
Cysteine Proteases/analysis , Neglected Diseases/prevention & control , Triage/statistics & numerical data , Trypanosoma cruzi/classification , Drug Discovery , Leishmania/classification , Pharmaceutical Preparations , Trypanosomatina/classification
6.
Mem. Inst. Oswaldo Cruz ; 112(4): 309-318, Apr. 2017. tab, graf
Article in English | LILACS | ID: biblio-841787

ABSTRACT

BACKGROUND Leishmaniases are a serious health problem in southeast Brazil, including the city of Belo Horizonte (BH), Minas Gerais state (MG), where there are high rates of incidence and mortality due to visceral leishmaniases. BH is divided into nine sanitary districts (SD) of which one, the Venda Nova SD, was selected for this study because it has high rates of positivity for canine leishmaniasis and high incidence of human leishmaniasis. OBJECTIVES This study aimed to survey the sand fly fauna in Venda Nova SD from August 2011 to July 2013 and perform a descriptive analysis of the vector population. METHODS The sampling was carried out using automatic HP light traps at all covered areas of the Venda Nova SD, in a total of eighteen light traps. Sampled specimens were identified following Galati (2003), and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A simple environmental description was done for it area and Kernel estimation was used to infer vector density for each study site. FINDINGS A total of 2,427 sand fly specimens belonging to eight species and five genera were collected of which 95.3% were Lutzomyia longipalpis. The seasonal variation curve was delineated by this species. Lu. longipalpis was the most abundant at all collection points and in all months of the study, and exhibited a natural infection rate of 1.01% for Leishmania infantum and 1.77% for Leishmania braziliensis. MAIN CONCLUSIONS The results show the presence and adaptation of Lu. longipalpis to the anthropic environment of BH and reinforces its role as the main vector of L. infantum in the region.


Subject(s)
Humans , Animals , Male , Female , Dogs , Psychodidae/classification , Psychodidae/parasitology , Leishmaniasis/transmission , DNA, Protozoan/analysis , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmania/classification , Leishmania/genetics , Seasons , Brazil , Population Density
7.
Mem. Inst. Oswaldo Cruz ; 112(2): 100-107, Feb. 2017. graf
Article in English | LILACS | ID: biblio-841760

ABSTRACT

BACKGROUND Leishmaniasis caused by Leishmania martiniquensis infection has been reported in human and domestic animals of Martinique Island, Germany, Switzerland, USA, Myanmar and Thailand. The peculiar clinical features of disseminated cutaneous and visceral forms co-existence render the urgent need of specific diagnostic tool to identify the natural sand fly vectors for effective prevention and control strategies. Loop-mediated isothermal amplification (LAMP) of 18S rRNA gene as well as polymerase chain reaction (PCR) of minicircle kinetoplast DNA gene (PCR-mkDNA) have never been applied to detect L. martiniquensis and L. siamensis in sand fly vectors. OBJECTIVE The present study was aimed to validate malachite green-LAMP (MG-LAMP) and PCR-mkDNA techniques to detect L. martiniquensis in sand fly vectors, compared with the conventional PCR of internal transcribed spacer 1 (PCR-ITS1). METHODS We compared the validity of LAMP of 18S rRNA gene and PCR-mkDNA, to PCR-ITS1 in simulation model of L. martiniquensis infection in Sergentomyia gemmea sand flies. Attributable to the sensitivity and specificity, PCR-mkDNA was consecutively applied to detect L. martiniquensis in 380 female sand fly individuals captured in the newly identified affected region of Lamphun Province, Thailand. FINDINGS AND MAIN CONCLUSIONS Results showed that PCR-mkDNA could detect at least one promastigote per sand fly, which was 10-time superior to LAMP and PCR-ITS1. In addition, PCR-mkDNA was more specific, able to differentiate L. martiniquensis from other viscerotropic Leishmania species, such as L. siamensis, L. (L.) donovani, and L. (L.) infantum. Consecutively, mass screening of L. martiniquensis in 380 female sand fly individuals by PCR-mkDNA was implemented in a new affected area of Thailand where a patient with leishmaniasis/HIV co-infection resides; however Leishmania DNA was undetected. In conclusion, PCR-mkDNA is a promising tool for molecular mass screening of L. martiniquensis infection in outbreak areas where several species of Leishmania and sand flies co-exist.


Subject(s)
Humans , Animals , Female , Leishmania/isolation & purification , Leishmania/classification , Leishmania/genetics , Thailand/epidemiology , DNA, Protozoan/genetics , DNA, Kinetoplast/genetics
8.
Mem. Inst. Oswaldo Cruz ; 112(1): 75-78, Jan. 2017. graf
Article in English | LILACS | ID: biblio-841757

ABSTRACT

Studies on the sandfly fauna to evaluate natural infection indexes are still limited in the Brazilian Amazon, a region with an increasing incidence of cutaneous leishmaniasis. Here, by using a multiplex polymerase chain reaction directed to Leishmania kDNA and hybridisation, we were able to identify L. (Viannia) subgenus in 12 out of 173 sandflies captured in the municipality of Rio Branco, Acre state, revealing a positivity of 6.94%. By sequencing the Leishmania 234 bp-hsp70 amplified products from positive samples, infection by L. (V.) braziliensis was confirmed in five sandflies: one Evandromyia saulensis, three Trichophoromyia auraensis and one Pressatia sp. The finding of L. (Viannia) DNA in two Ev. saulensis corresponds to the first record of possible infection associated with this sandfly. Moreover, our study reveals for the first time in Brazil, Th. auraensis and Pressatia sp. infected by L. (Viannia) parasites.


Subject(s)
Animals , Psychodidae/classification , Psychodidae/parasitology , Leishmaniasis, Cutaneous/transmission , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmania/classification , Brazil , Multiplex Polymerase Chain Reaction
9.
Rev. Soc. Bras. Med. Trop ; 49(5): 586-592, Sept.-Oct. 2016. tab, graf
Article in English | LILACS | ID: lil-798117

ABSTRACT

Abstract INTRODUCTION: Malaria and leishmaniasis are prevalent in tropical regions, which have environmental characteristics that are highly favorable to protozoa and vectors of these diseases; the transmission of these infections in sub-tropical regions, although recognized, represents only a small fraction of cases. Plants are constantly being used in the search for and acquisition of new drugs, and many compounds derived from them have been used to combat various diseases. In this study, we evaluated the action of the dichloromethanolic extract of Myrciaria dubia leaves against the protozoa Plasmodium falciparum, Leishmania amazonensis, Leishmania braziliensis, and Leishmania chagasi through bioassays. METHODS The extract from M. dubia was tested for its anti-P. falciparum activity in an anti-histidine-rich protein II immunosorbent assay. The antileishmanial assays were performed using the resazurin method, while cytotoxicity against human hepatoma (HepG2) strain was determined using the colorimetric MTT [3-(4, 5-dimethyl-2- thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide] method. RESULTS The M. dubia extract presented a half-maximal inhibitory concentration equal to 2.35 (1.05)μg/mL for P. falciparum, 190.73 (6.41) μg/mL for L. amazonensis, and greater than equal to 200µg/mL for L. chagasi and L. braziliensis strains. The cytotoxic concentration for 50% of the cells was above 500μg/mL for HepG2, indicating no toxicity and greater selectivity against parasites. CONCLUSIONS The results obtained indicate the presence of antiplasmodial and leishmanicidal bioactive compounds in the dichloromethanolic extracts of M. dubia leaves, and point towards future studies to elucidate the mechanism of action for each physiological effect.


Subject(s)
Humans , Plasmodium falciparum/drug effects , Plant Extracts/pharmacology , Myrtaceae/chemistry , Leishmania/drug effects , Antimalarials/pharmacology , Antiprotozoal Agents/pharmacology , Plant Extracts/toxicity , Immunoenzyme Techniques , Colorimetry , Inhibitory Concentration 50 , Parasitic Sensitivity Tests , Hep G2 Cells/drug effects , Leishmania/classification , Antimalarials/isolation & purification , Antimalarials/toxicity , Antiprotozoal Agents/isolation & purification , Antiprotozoal Agents/toxicity
10.
Rev. Soc. Bras. Med. Trop ; 49(4): 398-407, July-Aug. 2016. tab, graf
Article in English | LILACS | ID: lil-792794

ABSTRACT

Abstract: Visceral leishmaniasis (VL) is one of the most important tropical diseases worldwide. Although chemotherapy has been widely used to treat this disease, problems related to the development of parasite resistance and side effects associated with the compounds used have been noted. Hence, alternative approaches for VL control are desirable. Some methods, such as vector control and culling of infected dogs, are insufficiently effective, with the latter not ethically recommended. The development of vaccines to prevent VL is a feasible and desirable measure for disease control; for example, some vaccines designed to protect dogs against VL have recently been brought to market. These vaccines are based on the combination of parasite fractions or recombinant proteins with adjuvants that are able to induce cellular immune responses; however, their partial efficacy and the absence of a vaccine to protect against human leishmaniasis underline the need for characterization of new vaccine candidates. This review presents recent advances in control measures for VL based on vaccine development, describing extensively studied antigens, as well as new antigenic proteins recently identified using immuno-proteomic techniques.


Subject(s)
Humans , Animals , Dogs , Antibodies, Protozoan/immunology , Protozoan Vaccines/immunology , Leishmania/immunology , Leishmaniasis, Visceral/prevention & control , Antigens, Protozoan/immunology , Protozoan Proteins/immunology , Leishmania/classification
11.
Mem. Inst. Oswaldo Cruz ; 110(8): 1024-1034, Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769826

ABSTRACT

The herbaceous shrub Tetradenia riparia has been traditionally used to treat inflammatory and infectious diseases. Recently, a study showed that T. riparia essential oil (TrEO) obtained in summer has antileishmanial effects, although these results could be influenced by seasonal variation. This study evaluated the activity of the TrEO obtained in different seasons against Leishmania (Leishmania) amazonensis, in vitro and in vivo. The compounds in the TrEO were analysed by gas chromatography-mass spectrometry; terpenoids were present and oxygenated sesquiterpenes were the majority compounds (55.28%). The cytotoxicity and nitric oxide (NO) production were also tested after TrEO treatment. The TrEO from all seasons showed a 50% growth inhibitory concentration for promastigotes of about 15 ng/mL; at 30 ng/mL and 3 ng/mL, the TrEO reduced intracellular amastigote infection, independently of season. The TrEO from plants harvested in summer had the highest 50% cytotoxic concentration, 1,476 ng/mL for J774.A1 macrophages, and in spring (90.94 ng/mL) for murine macrophages. NO production did not change in samples of the TrEO from different seasons. The antileishmanial effect in vivo consisted of a reduction of the parasite load in the spleen. These results suggest that the TrEO has potential effects on L. (L.) amazonensis, consonant with its traditional use to treat parasitic diseases.


Subject(s)
Animals , Female , Antiprotozoal Agents/pharmacology , Lamiaceae/chemistry , Leishmania/drug effects , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Antiprotozoal Agents/isolation & purification , Cytotoxins/pharmacology , Gas Chromatography-Mass Spectrometry , Growth Inhibitors/pharmacology , In Vitro Techniques , Leishmania/classification , Lymph Nodes/parasitology , Mice, Inbred BALB C , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/parasitology , Nitric Oxide/analysis , Oils, Volatile/chemistry , Parasite Load , Plant Extracts/chemistry , Plant Leaves/chemistry , Seasons , Sesquiterpenes/analysis , Spleen/parasitology , Time Factors
12.
Braz. j. otorhinolaryngol. (Impr.) ; 81(5): 533-540, Sept.-Oct. 2015. tab, graf
Article in English | LILACS | ID: lil-766282

ABSTRACT

ABSTRACT INTRODUCTION: Mucosal leishmaniosis (ML) is a severe clinical form of leishmaniosis. Complex factors related to the parasite and the host are attributed to the development of mucosal lesions. Leishmania RNA virus 1 (LRV1) can disrupt immune response, and may be the main determinant of severity of the disease; it should be investigated. OBJECTIVE: To study the existence of clinical differences between patients with ML with endosymbiosis by LRV1 and. those without it. METHODS: A cross-sectional cohort study with clinical evaluation, polymerase chain reaction (PCR) detection of Leishmania, species classification, and search of LRV1 was performed. Only patients with confirmed diagnosis of ML by positive PCR and with nasal mucosa injuries were included in this analysis. RESULTS: Out of 37 patients, 30 (81.1%) were diagnosed with Leishmania braziliensis, five (13.5%) with Leishmania guyanensis, and two (5.4%) with mixed infection of L. braziliensis and L. guyanensis. LVR1 virus was present in 26 (70.3%) of the cases. CONCLUSION: Correlation between clinical phenotype and presence of LRV1 was not observed, although the frequency of the virus is two-fold higher in mucosal lesions than that found in the literature on skin lesions in the same geographical area.


RESUMO Introdução: A leishmaniose de mucosa (LM) é uma forma clínica grave da leishmaniose. Fatores complexos ligados ao parasita e ao hospedeiro são atribuídos ao desenvolvimento das lesões de mucosa. Leishmania RNA Vírus 1 (LRV1) pode subverter a resposta imune, podendo ser o principal determinante da gravidade da doença e deve ser pesquisado. Objetivo: Estudar a existência de diferenças clínicas entre pacientes portadores de LM com endosimbiose por LRV1 e as que não possuem. Métodos: Foi realizado um estudo de coorte histórica com corte transversal com avaliação clínica, detecção da Leishmania por técnica de PCR, classificação da espécie e pesquisa de LRV1. Foram incluídos na análise da pesquisa somente os pacientes com diagnóstico confirmado de LM com PCR positivo, com lesão de mucosa nasal. Resultados: Dos 37 pacientes, 30 (81,1%) foram diagnosticados com L. braziliensis, 5 (13,5%) com L. guyanensis e 2 (5,4%) com infecção mista de L. braziliensis e L. guyanensis. O vírus LVR1 estava presente em 26 casos (70,3%). Conclusão: A correlação entre o fenótipo clínico e a presença do LRV1 não foi constatada, porém a frequência do vírus é duas vezes maior em lesão de mucosa do que encontrado em trabalho, da mesma região, sobre lesão cutânea.


Subject(s)
Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Young Adult , Leishmania/virology , Leishmaniasis, Mucocutaneous/virology , Leishmaniavirus/genetics , Nasal Mucosa/parasitology , RNA Viruses/genetics , Cohort Studies , Cross-Sectional Studies , Leishmania/classification , Leishmaniasis, Mucocutaneous/genetics , Phenotype , Polymerase Chain Reaction , Severity of Illness Index
13.
Rev. Soc. Bras. Med. Trop ; 48(5): 560-567, Sept.-Oct. 2015. graf
Article in English | LILACS | ID: lil-763329

ABSTRACT

ABSTRACTINTRODUCTION:The aim of this study was quantify annexin A1 expression in macrophages and cluster of differentiation 4 (CD4) + and cluster of differentiation 8 (CD8)+ T cells from the skin of patients with cutaneous leishmaniasis (n=55) and correlate with histopathological aspects.METHODS:Infecting species were identified by polymerase chain reaction-restriction fragment length polymorphism, and expression of annexin A1 was analyzed by immunofluorescence.RESULTS:All patients (n = 55) were infected with Leishmania braziliensis . Annexin A1 was expressed more abundantly in CD163 + macrophages in infected skin (p < 0.0001) than in uninfected skin. In addition, macrophages in necrotic exudative reaction lesions expressed annexin A1 at higher levels than those observed in granulomatous (p < 0.01) and cellular lesions p < 0.05). This difference might be due to the need to clear both parasites and necrotic tissue from necrotic lesions. CD4 + cells in cellular lesions expressed annexin A1 more abundantly than did those in necrotic (p < 0.05) and granulomatous lesions (p < 0.01). Expression in CD8 + T cells followed the same trend. These differences might be due to the pervasiveness of lymphohistiocytic and plasmacytic infiltrate in cellular lesions.CONCLUSIONS:Annexin A1 is differentially expressed in CD163 + macrophages and T cells depending on the histopathological features of Leishmania -infected skin, which might affect cell activation.


Subject(s)
Female , Humans , Male , Middle Aged , Annexin A1/metabolism , Leishmania/classification , Leishmaniasis, Cutaneous/metabolism , Leishmaniasis, Cutaneous/pathology , Annexin A1/analysis , Cross-Sectional Studies , Fluorescent Antibody Technique , Leishmaniasis, Cutaneous/parasitology , Macrophages/metabolism , Macrophages/parasitology , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length
14.
Rev. Inst. Med. Trop. Säo Paulo ; 57(4): 343-347, July-Aug. 2015. tab, ilus
Article in English | LILACS | ID: lil-761162

ABSTRACT

SUMMARYIn this study, Leishmaniaspecies were identified by Polymerase Chain Reaction (PCR). The epidemiology of patients suspected of having American Cutaneous Leishmaniasis in the municipality of Assis Brasil, Acre State, located in the Brazil/Peru/Bolivia triborder was also investigated. By PCR, the DNA of Leishmaniawas detected in 100% of the cases (37 samples) and a PCR-Restriction Fragment Length Polymorphism (RFLP) of the hsp 70gene identified the species in 32 samples: Leishmania (Viannia) braziliensis (65.6%) , L. (V.) shawi (28.1%) , L. (V.) guyanensis (3.1%) and mixed infection L. (V.) guyanensisand L. (Leishmania) amazonensis(3.1%)This is the first report of L. (V.) shawiand L. (L.) amazonensisin Acre. The two predominant species were found in patients living in urban and rural areas. Most cases were found in males living in rural areas for at least three years and involved in rural work. This suggests, in most cases, a possible transmission of the disease from a rural/forest source, although some patients had not engaged in activities associated with permanence in forestall areas, which indicate a possible sandflies adaptation to the periurban setting.


RESUMOO presente estudo caracterizou as espécies de Leishmaniapela Reação em Cadeia da Polimerase (PCR). Também descreveu os aspectos epidemiológicos de pacientes com suspeita de leishmaniose tegumentar americana do município de Assis Brasil, Estado do Acre, Brasil, localizado na tríplice fronteira Brasil/Peru/Bolívia. A PCR detectou DNA de Leishmaniaem 100% dos casos (37 amostras) e a PCR- Restriction Fragment Length Polymorfism(RFLP) do gene hsp 70identificou as espécies em 32 amostras: Leishmania (Viannia) braziliensis (65,6%) , L. (V.) shawi (28,1%) , L. (V.) guyanensis (3,1%) e infecção mista L. (V.) guyanensise L. (Leishmania) amazonensis(3,1%)Esse é o primeiro registro de L. (V.) shawie L. (L.) amazonensisno Acre. As duas espécies predominantes foram encontradas em indivíduos residentes em áreas rurais e urbanas. O maior número de casos foi notificado entre indivíduos de áreas rurais, sexo masculino, de ocupação rural e tempo de residência maior que três anos. Esses dados sugerem possível transmissão da doença em ambiente rural/florestal na maioria dos casos, no entanto alguns pacientes não tinham envolvimento com atividades relacionadas com a permanência na floresta, indicando possível adaptação de flebotomíneos no ambiente periurbano.


Subject(s)
Humans , Animals , Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Young Adult , Leishmania/classification , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Mucocutaneous/parasitology , Brazil/epidemiology , Leishmania/genetics , Leishmania/isolation & purification , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Mucocutaneous/diagnosis , Leishmaniasis, Mucocutaneous/epidemiology , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Risk Factors , Rural Population , Urban Population
15.
Exp. Parasitol ; 157: 156-162, 2015.
Article in English | SES-SP, LILACS, SES-SP, SESSP-IALPROD, SES-SP, SESSP-IALACERVO | ID: biblio-1022550

ABSTRACT

Visceral leishmaniasis represents an important public health issue in different parts of the world, requiring that measures be put in place to control the spread of the disease worldwide. The canine leishmaniasis diagnosis is not easy based on clinical signs, since dogs may not develop the infection with recognizable signs. Thus, the laboratorial diagnosis is essential to ascertain the incidence and prevalence of canine leishmaniasis especially in areas with major control efforts. Although, the diagnosis can be performed by the use of different approaches, the molecular methods such as PCR have become an indispensable tool for leishmaniases diagnosis. A TaqMan assay for real-time PCR (Linj31-qPCR) was developed to determine the parasite occurrence in clinical cases of leishmaniasis. The assay targets an L. (L.) infantum hypothetical protein region. The specificity of the assay was verified by using Leishmania World Health Organization reference strains including parasites belonging to subgenus L. (Leishmania), subgenus L. (Viannia), other Leishmania species and Trypanosoma cruzi. The sensitivity was verified by using isolates of L. (L.) amazonensis and L. (L.) infantum. The usefulness of the assay for diagnosis was ascertained by testing 277 samples from dogs in regions endemic for visceral and/or cutaneous leishmaniasis and from regions in which leishmaniasis was not endemic in São Paulo State, Brazil. Diagnosis of canine visceral leishmaniasis (CVL) was determined on these animals by conventional PCR and three serological tests. The dog samples were divided into four groups. I, dogs with CVL (n = 101); II, dogs with other diseases and without CVL (n = 97); III, dogs with American cutaneous leishmaniasis (n = 7), and, IV, dogs without CVL (n = 72) from areas where leishmaniasis was not endemic as control group. Results indicated that Linj31-qPCR was able to identify parasites belonging to subgenus L. (Leishmania) with no cross-amplification with other parasite subgenera. The Linj31-qPCR detected Leishmania parasites DNA in 98% of samples from Group I. In conclusion this methodology can be used as routine diagnostic tools to detect parasites from subgenus Leishmania.


Subject(s)
Animals , Reference Standards , Protozoan Proteins/genetics , DNA, Protozoan/chemistry , Sensitivity and Specificity , Leishmania infantum/genetics , Leishmania infantum/chemistry , Dog Diseases/diagnosis , Dog Diseases/parasitology , Dogs , Leishmania/classification , Leishmania/genetics , Leishmania/chemistry , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/parasitology , Leishmaniasis, Visceral/veterinary , Animals
16.
Recife; s.n; 2015. 61 p. ilus, graf, tab, mapas.
Thesis in Portuguese | LILACS | ID: lil-751031

ABSTRACT

A Leishmaniose Tegumentar Americana (LTA) é causada por protozoários, do gênero Leishmania, envolvidos em um complexo ciclo biológico. No Brasil, sete espécies estão envolvidas com a etiologia da doença, distribuídas em todas as regiões geográficas e responsáveis por diferentes manifestações clínicas. Diante disso, o diagnóstico em conjunto com a identificação da espécie é de grande importância clínico-terapêutica. Este trabalho tem por objetivo avaliar a aplicabilidade da técnica de PCR quantitativa em tempo real (qPCR) para identificação de espécies de Leishmania envolvidas com a etiologia da LTA. Foram realizados ensaios de qPCR para padronização da Temperatura de melting (Tm) utilizando cepas de referência de diferentes espécies de Leishmania. Após o diagnóstico em amostras de sangue de animais domésticos utilizando a qPCR, as amostras positivas foram analisadas através de suas Tm, e os produtos de qPCR foram purificados e sequenciados. Dez amostras previamente caracterizadas por isoenzimas, também foram analisadas através da Tm. Ainda como teste de referência, foi padronizada uma Restriction Fragment Length Polymorphism (RFLP) utilizando as cepas de referência e testada nas amostras. Através da padronização da Tm das espécies, foram criados dois intervalos de análise: 1 (Tm = 78-79,99°C), que compreende: Leishmania (V.) braziliensis, Leishmania (V.) panamensis, Leishmania (V.) lainsoni, Leishmania (V.) guyanensis e Leishmania (V.) shawi; e 2 (Tm = 80-82,2°C), que compreende: Leishmania (V.) naiffi, Leishmania (L.) amazonensis e Leishmania (L.) mexicana. Um total de 223 amostras positivas foi analisado, destas, 58 incluídas no intervalo 1 e 165 no intervalo 2. O sequencimento de 94 destas amostras foi correspondente à L. (V.) braziliensis, L. (V.) panamensis e L. (V.) guyanensis. A RFLP em 173 amostras identificou 167 L. (V.) braziliensis, 05 L. (L.) mexicana e 01 L. (V.) panamensis...


The American Cutaneous Leishmaniasis (ACL) is caused by protozoa of the genus Leishmania, involved in a complex biological cycle. In Brazil, seven species are involved in the etiology of the disease, distributed in all geographic regions and responsible for different clinical manifestations. Therefore, the diagnosis together with the identification of the species is of great clinical and therapeutic importance. This work aims to evaluate the applicability of the technique of real-time quantitative PCR (qPCR) for the identification of Leishmania species involved in the etiology of ACL. qPCR assays for standardizing the melting temperature (Tm) using reference strains of different species of Leishmania were performed. After the diagnosis on blood samples of domestic animals using the qPCR positive samples were analyzed by their Tm and qPCR products were purified and sequenced. Ten samples previously characterized by isoenzymes were also analyzed by Tm. Also as a reference test was standardized as Restriction Fragment Length Polymorphism (RFLP) using the reference strains and tested on samples. Through standardization of Tm species two ranges of analysis were created: 1 (Tm = 78-79,99°C), comprising: Leishmania (V.) braziliensis, Leishmania (V.) panamensis, Leishmania (V.) lainsoni, Leishmania (V.) guyanensis e Leishmania (V.) shawi; and, 2 (Tm = 80-82,2°C), comprising: Leishmania (V.) naiffi, Leishmania (L.) amazonensis e Leishmania (L.) mexicana. A total of 223 positive samples were analyzed, of these, 58 included in the range 1 and 165 in the range 2 to 94 and the sequence of these samples corresponded to L. (V.) braziliensis, L. (V.) panamensis and L. (V.) guyanensis. By RFLP in 173 samples were identified 167 L. (V.) braziliensis, 05 L. (L.) mexicana and 01 L. (V.) panamensis The analysis of Tm of the ten samples characterized by isoenzymes showed 80% agreement (p = 0.6499) between the gold standard (isoenzymes) and intervals developed in this study...


Subject(s)
Humans , Animals , Cats , Dogs , Leishmania/classification , Leishmania/isolation & purification , Leishmaniasis, Cutaneous/diagnosis , Nucleic Acid Denaturation , Real-Time Polymerase Chain Reaction/methods , Amplified Fragment Length Polymorphism Analysis , Brazil , Sensitivity and Specificity , Sequence Analysis, DNA
17.
Rio de Janeiro; s.n; 2014. viii,110 p. ilus, graf, tab, mapas.
Thesis in Portuguese | LILACS | ID: lil-736963

ABSTRACT

Métodos moleculares estão sendo cada vez mais empregados para diagnóstico, estudos taxonômicos, filogenéticos e epidemiológicos envolvendo este parasita. [...] O principal objetivo deste trabalho foi desenvolver marcadores multilocus para Leishmania (Viannia) e avaliar sua aplicabilidade em estudos epidemiológicos. Os objetivos específicos incluíram: i) o desenvolvimento de um painel multi locus sequence analisys (MLSA) para cepas de Leishmania (Viannia) que circulam no Brasil que permita, concomitantemente, a identificação de isolados e a realização de estudos filogenéticos; ii) o estudo da estrutura da população de cepas de Leishmania (Viannia) quanto à clonalidade e ocorrência de eventos de recombinação pela determinação de perfis de microssatélites; iii) avaliação da aplicabilidade do painel MLSA como ferramenta epidemiológica para as leishmanioses; iv) a descrição de eventos moleculares em leishmânia que podem interferir nos resultados obtidos a partir de marcadores moleculares empregados...


Molecular methods have been often applied for diagnosis, studies oftaxonomy, phylogeny and epidemiology. [...] The main objective ofthis study was to develop multi locus markers for Leishmania (Viannia) and to evaluate its applicability in epidemiological studies. The specific objectives were: i) to develop a multi locus sequence analyses (MLSA) panel with Leishmania (Viannia) strains from Brazil that allows the species identification and phylogenetic inferences to be performed; ii) to execute a population structure study through microsatellites profiles (MLMT); iii) to evaluate the MLSA panel as anepidemiological tool; iv) to describe molecular events that may interfere in the results obtained by the molecular markers employed. After MLSA and MLMT, the results could be compared. MLMT defined two main populations, one comprising L. (V.) guyanensis and other L. (V.) braziliensis strainsfrom the Atlantic coast; recombination signs were detected for both. A third group, quite heterogeneous, included L. (V.) braziliensis strains from northern Brazil and the other species L. (V.)shawi, L. (V.) naiffi, and L. (V.) lainson...


Subject(s)
Humans , Leishmania/classification , Leishmania/genetics , Leishmaniasis, Cutaneous/epidemiology , Molecular Epidemiology
18.
Rio de Janeiro; s.n; 2014. xvii,124 p. ilus, tab, graf, mapas.
Thesis in Portuguese | LILACS | ID: lil-751002

ABSTRACT

A Leishmania Leishmania amazonensis é um importante agente etiológico da leishmaniose tegumentar em humanos no Brasil. Este parasito apresenta mecanismos de adaptação que podem ser guiados por suas proteases onde se destacam as cisteíno proteases CP, sendo a CPB a mais estudada dentre as CPs já descritas em Leishmania spp. O foco deste trabalho é a região COOH terminal da CPB cyspep, por suas reconhecidas propriedades modulatórias sobre o sistema imune de camundongos. No presente estudo busca se propor um modelo estrutural da cyspep visando estabelecer sua relação estrutura função. O estudo foi conduzido por abordagem in silico, desenvolvendo o modelo tridimensional através de técnicas de modelagem comparativa, threading e métodos de novo, e analisando a estabilidade estrutural por dinâmica molecular. A associação do uso de servidores online que utilizam as abordagens de modelagem comparativa, threading e métodos de novo para predição tridimensional de proteínas foi favorável à resolução de 72 modelos da cyspep. Através de informações sobre predição de estrutura secundária e ligações dissulfeto, dos modelos gerados para cyspep, 11 foram selecionados para simulações de dinâmica molecular, sendo dois modelos obtidos por modelagem comparativa Comp, Fugue, 5 por threading IT1, M4, M8, L3 e SP5 e 4 por métodos de novo Q5, Q7, D9 e R1. Os 11 modelos foram submetidos a simulação por dinâmica molecular por um tempo de 200 ns. Os modelos Fugue e IT1 também foram submetidos a simulações de dinâmica molecular sob a influência de diferentes campos de força para melhor avaliar seu conteúdo de estrutura secundária. Nossos resultados sugerem que a cyspep pode adotar uma conformação composta principalmente de folhas beta, as quais se mantiveram estáveis após longas simulações de dinâmica molecular sob a influência de diferentes campos de força; enquanto o teor helicoidal foi rapidamente desfeito...


Leishmania (Leishmania) amazonensis is an important etiological agent of cutaneous leishmaniasis in humans, in Brazil. This parasite has adaptive mechanisms that can be modulated by their proteases, characterizing the cysteine protease (CP) as themost extensively studied CPB among the CPs described for Leishmania spp. This work was focused on the COOH-terminal region of CPB (cyspep), recognized for their modulatory properties on the immune system of mice. This present study aims topropose a structural model for the cyspep trying to determine its structure-function relationship. The present study was conducted by in silico to develop a three-dimensional model using comparative modeling, threading and de novo methods, andmolecular dynamics to analyze its structural stability. The association of many online servers using the approaches of comparative modeling, threading and de novo methods for the prediction of the three-dimensional structure of protein was favorablefor the achievement of 72 three-dimensional models for cyspep. Through secondary structure and disulfide bonds prediction, out of the 72 models generated for cyspep, 11 were selected for molecular dynamics simulations, of which 2 models were obtained by comparative modeling (Comp, Fugue), 5 by threading (IT1, M4, M8, L3and SP5) and 4 de novo methods (Q5, Q7, D9 and R1). The eleven models were submitted to molecular dynamics simulations for a computational time of 200 ns. The Fugue and IT1 models were also subjected to molecular dynamics simulations under different force fields to better assess their secondary structure content and determinethe impact of the force field on the structure. Our results suggest that the cyspep might adopt a conformation composed of mostly beta-sheets, which remained stable after long molecular dynamics simulations under the influence of different force fields while the helical content was rapidly disrupted...


Subject(s)
Cysteine Endopeptidases , Leishmania/classification , Protein Conformation
19.
Rev. bras. parasitol. vet ; 22(2): 297-299, Apr./June/2013. graf
Article in English | LILACS | ID: lil-679412

ABSTRACT

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 visceral 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.


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.


Subject(s)
Animals , Leishmania/isolation & purification , Porcupines/parasitology , Brazil , Leishmania/classification
20.
Rev. patol. trop ; 41(3): 356-366, jul.-set. 2012. ilus
Article in Spanish | LILACS | ID: lil-664769

ABSTRACT

En la región litoral o costa ecuatoriana existen 5 especies de Leishmania que afectan al ser humano, con un amplio espectro de lesiones cutáneas y linfáticas bien documentadas. Las lesiones en la mucosa rino-oro-faríngea y aún laríngea, no son reportadas con frecuencia. Se presentan cuatrocasos con esta afección, de origen indudable del litoral: 1) la lesión mucosa aparece luego de 25 años de la lesión dérmica; 2) las cicatrices de la piel en la cara y las lesiones de mucosa nasal, muy próximas; 3) Lesiones muy graves de todo el área, incluye laringe; 4) Lesión dérmica en pierna y lesión nasal al cabo de 7 años. Este reporte permite actualizar esta dolencia en el diagnóstico diferencial y ofrecer mejor tratamiento y pronóstico a los pacientes.


Subject(s)
Humans , Male , Female , Adult , Leishmania/classification , Leishmaniasis, Diffuse Cutaneous/diagnosis , Ecuador/epidemiology
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