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1.
Rev Bras Parasitol Vet ; 29(2): e003520, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520088

RESUMO

Blood samples and swabs from ocular conjunctiva and mouth were obtained from 64 cats. Of 64 serum samples, 19 were positive for Leishmania antibodies by ELISA (29.80%). Eight cats were positive by PCR (12.5%) in swab samples from mouth and/or ocular mucosa. Poor kappa agreement between serological and molecular results (k = 0.16) was obtained. From five positive PCR samples one was L. braziliensis and four were L. infantum. Phylogenetic analysis performed with the five isolates of Leishmania, showed that samples of L. infantum isolated from the cats were phylogenetically close to those isolated from domestic dogs in Brazil, while the L. braziliensis is very similar to the one described in humans in Venezuela. The study demonstrated that, despite high seropositivity for Leishmania in cats living in the study region, poor agreement between serological and molecular results indicate that positive serology is not indicative of Leishmania infection in cats. Parasite DNA can be detected in ocular conjunctiva and oral swabs from cats, indicating that such samples could be used for diagnosis. Results of phylogenetic analyzes show that L. infantum circulating in Brazil is capable of infecting different hosts, demonstrating the parasite's ability to overcome the interspecies barrier.


Assuntos
Doenças do Gato/parasitologia , Leishmania braziliensis/isolamento & purificação , Leishmania infantum/isolamento & purificação , Leishmaniose/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Doenças do Gato/diagnóstico , Gatos , DNA de Protozoário/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Leishmania braziliensis/genética , Leishmania braziliensis/imunologia , Leishmania infantum/genética , Leishmania infantum/imunologia , Leishmaniose/diagnóstico , Filogenia , Reação em Cadeia da Polimerase/veterinária
2.
Intern Med ; 59(9): 1227-1230, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378656

RESUMO

Liposomal-amphotericin B (L-AmB) is used for cutaneous leishmaniasis (CL); however, its treatment failure has not yet been described in detail. A 58-year-old man returned from the Republic of Venezuela with a cutaneous ulcer on his left lower leg. The causative pathogen was Leishmania braziliensis. We started L-AmB 3 mg/kg/day for 6 days; however, the ulcer did not resolve. The patient was successfully retreated with a higher dose L-AmB 4 mg/kg/day 9 times (total, 36 mg/kg). If L-AmB fails to treat CL and other therapeutics cannot be used, increasing the L-AmB dose is a viable option.


Assuntos
Anfotericina B/uso terapêutico , Antiprotozoários/uso terapêutico , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Anfotericina B/administração & dosagem , Antiprotozoários/administração & dosagem , Diagnóstico Diferencial , Relação Dose-Resposta a Droga , Humanos , Leishmaniose Cutânea/complicações , Leishmaniose Cutânea/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Retratamento , Falha de Tratamento
3.
Am J Trop Med Hyg ; 102(6): 1319-1322, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32228792

RESUMO

The six previously reported civilian cases of mucosal leishmaniasis (ML) diagnosed in the United States have all represented imported New World ML. We describe two new patients with ML diagnosed in New York City-a Syrian immigrant with a nasal mass (Leishmania tropica), the first report of Old World ML in the United States, and an American ecologist who worked in Bolivia and had been treated for cutaneous infection 23 years before developing lesions (L. (Viannia) braziliensis) initially of the uvula, soft palate, and posterior pharynx and subsequently the larynx.


Assuntos
Leishmaniose Mucocutânea/epidemiologia , Leishmaniose Mucocutânea/patologia , Idoso , Anfotericina B/uso terapêutico , Antiprotozoários/uso terapêutico , Humanos , Leishmania braziliensis/isolamento & purificação , Leishmaniose Mucocutânea/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , Fosforilcolina/análogos & derivados , Fosforilcolina/uso terapêutico
4.
BMC Infect Dis ; 19(1): 1015, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783798

RESUMO

BACKGROUND: The present study aimed to demonstrate the applicability of a flow cytometry-based serology approach to identify spontaneous cure by the detection of immunoglobulin G, and also, the diagnosis and cure criterion by the IgG1 isotype in American Tegumentary Leishmaniasis - ATL caused by L. (V.) braziliensis. Also, a comparison between flow cytometry with the serological conventional technique was performed. METHODS: Forty five individuals were included in study. They were assessed in two moments: First, 8 subjects spontaneously cured of ATL, 8 healthy individuals and 15 patients who had a positive diagnosis for ATL were selected before treatment to identify spontaneous cure by immunoglobulin G detection. Secondly, 14 patients who were positive for ATL were selected and had their blood collected before and 1, 2 and 5 years after treatment, respectively, for the diagnostic tests (ELISA and flow cytometry) and cure criterion evaluation using the IgG1 isotype. RESULTS: The analysis of the mean percentage of positive fluorescent parasites (PPFP) along with the titration curves of IgG anti-fixed promastigotes of L.(V.)braziliensis, confirmed the applicability of this method for monitoring spontaneous cure in ATL with outstanding co-positivity (100%) and co-negativity (100%) performance indexes. Regarding the results of the comparison between flow cytometry and ELISA it was seen that there was a better accuracy of the first one in relation to the other. When IgG1 applicability was evaluated, it was observed that before treatment, 36.8% of the patients were negative; in patients 1 year post-treatment, 82.3%; 2 years post-treatment, 27.2% and in patients 5 years post-treatment, 87.5%. The overall analysis of the results suggests that flow cytometry can be applied to ATL detection, and that the use of IgG1 isotype has possibilities to contribute as a more specific diagnostic method. CONCLUSIONS: Therefore, this area has great perspectives use for the diagnosis and cure criterion, and also it can be scaled up with the possibility to characterize the different clinical stages of the disease. Together, these findings demonstrate the applicability of a flow cytometry-based serology approach and opens up new avenues of research with this technique, such as the understanding the humoral response in ATL patients.


Assuntos
Leishmania braziliensis/imunologia , Leishmaniose Cutânea/diagnóstico , Anticorpos Antiprotozoários/sangue , Antiprotozoários/uso terapêutico , Área Sob a Curva , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Imunoglobulina G/sangue , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/tratamento farmacológico , Curva ROC , Remissão Espontânea
5.
J Pharm Pharmacol ; 71(12): 1784-1791, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31579947

RESUMO

The alkylaminoalkanethiosulfuric acids (AAATs) are amphipathic compounds effective against experimental schistosomiasis, of low toxicity, elevated bioavailability after a single oral dose and prompt tissue absorption. OBJECTIVES: To explore the in-vitro antileishmanial potential of AAATs using five compounds of this series against Leishmania (Viannia) braziliensis. METHODS: Their effects on promastigotes and axenic amastigotes, and cytotoxicity to macrophages were tested by the MTT method, and on Leishmania-infected macrophages by Giemsa stain. Effects on the mitochondrial membrane potential of promastigotes and axenic amastigotes and DNA of intracellular amastigotes were tested using JC-1 and TUNEL assays, respectively. KEY FINDINGS: The 2-(isopropylamino)-1-octanethiosulfuric acid (I) and 2-(sec-butylamino)-1-octanethiosulfuric acid (II) exhibit activity against both promastigotes and intracellular amastigotes (IC50 25-35 µm), being more toxic to intracellular parasites than to the host cell. Compound I induced a loss of viability of axenic amastigotes, significantly reduced (30%) the mitochondrial membrane potential of both promastigotes and axenic amastigotes and promoted selective DNA fragmentation of the nucleus and kinetoplast of intracellular amastigotes. CONCLUSIONS: In this previously unpublished study of trypanosomatids, it is shown that AAATs could also exhibit selective antileishmanial activity, a new possibility to be investigated in oral treatment of leishmaniasis.


Assuntos
Antiprotozoários/farmacologia , Leishmania braziliensis/isolamento & purificação , Leishmaniose/tratamento farmacológico , Ácidos Sulfúricos/farmacologia , Administração Oral , Animais , Antiprotozoários/administração & dosagem , Antiprotozoários/química , Concentração Inibidora 50 , Leishmania braziliensis/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Relação Estrutura-Atividade , Ácidos Sulfúricos/administração & dosagem , Ácidos Sulfúricos/química
6.
Biomedica ; 39(Supl. 2): 58-65, 2019 08 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31529834

RESUMO

INTRODUCTION: Mucosal leishmaniasis has a progressive course and can cause deformity and even mutilation in the affected areas. It is endemic in the American continent and it is mainly caused by Leishmania (Viannia) braziliensis. OBJECTIVE: To describe a series of mucosal leishmaniasis cases and the infectious Leishmania species. MATERIALS AND METHODS: We included 50 patients with a clinical diagnosis of mucosal leishmaniasis and parasitological confirmation, and we described their clinical and laboratory results. We performed species typing by PCR-RFLP using the miniexon sequence and hsp70 genes; confirmation was done by sequencing. RESULTS: The median time of disease evolution was 2.9 years (range: 1 month to 16 years). The relevant clinical findings included mucosal infiltration (94%), cutaneous leishmaniasis scar (74%), total loss of the nasal septum (24%), nasal deformity (22%), and mucosal ulceration (38%). The symptoms reported included nasal obstruction (90%), epistaxis (72%), rhinorrhea (72%), dysphonia (28%), dysphagia (18%), and nasal pruritus (34%). The histopathological study revealed a pattern compatible with leishmaniasis in 86% of the biopsies, and amastigotes were identified in 14% of them. The Montenegro skin test was positive in 86% of patients, immunofluorescence in 84%, and culture in 8%. Leishmania (V.) braziliensis was identified in 88% of the samples, L. (V) panamensis in 8%, and L. (V.) guyanensis and L. (L.) amazonensis in 2% respectively. CONCLUSION: In this study, we found a severe nasal disease with destruction and deformity of the nasal septum in 25% of the cases, probably associated with late diagnosis. Leishmania (V.) braziliensis was the predominant species. We described a case of mucosal leishmaniasis in Colombia caused by L. (L.) amazonensis for the first time.


Assuntos
Leishmania braziliensis/isolamento & purificação , Leishmania guyanensis/isolamento & purificação , Leishmaniose Mucocutânea/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Colômbia/epidemiologia , DNA de Protozoário/genética , Feminino , Genes de Protozoários , Proteínas de Choque Térmico HSP70/genética , Humanos , Leishmania braziliensis/classificação , Leishmania braziliensis/genética , Leishmania guyanensis/classificação , Leishmania guyanensis/genética , Leishmaniose Mucocutânea/complicações , Leishmaniose Mucocutânea/epidemiologia , Leishmaniose Mucocutânea/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Proteínas de Protozoários/genética , Análise de Sequência de DNA , Pele/parasitologia , Especificidade da Espécie , Adulto Jovem
7.
Int J Dermatol ; 58(11): 1323-1328, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31524286

RESUMO

BACKGROUND: American cutaneous leishmaniasis (ACL) is endemic in French Guiana. Its epidemiology is evolving, notably because of immigration, anthropization of natural areas, and new microbiological methods. Our first objective was to update epidemiological data. Our second objective was to look for risk factors of ACL. METHODS: This multicentric study was conducted from October 2017 to June 2018 in French Guiana. Patients with suspicion of mucocutaneous leishmaniasis were included in case of positive smear, culture, or PCR-RFLP on skin biopsy. RESULTS: One hundred and twenty-three patients met the inclusion criteria. Among those patients, 59.3% were Brazilian, mostly gold miners. Most of them (58%) were between 16 and 40 years old, and 69% were male. A large proportion of patients lived in traditional wooden houses (51%). Patients living in coastal towns were usually infected during trips to the primary forest (60%) and had a shorter time to diagnosis than workers of the hinterland. Among environmental risk factors, the presence of a water spring (40%) and dogs around houses (40%) were frequently reported. Leishmania guyanensis represented 80% of cases, followed by Leishmania braziliensis (6%), Leishmania naiffi (2%), and Leishmania amazonensis (1%). CONCLUSIONS: Gold mining and trips to the primary forest represent high-risk situations for ACL in French Guiana, where the population of infected patients is dominated by Brazilian immigrants. Possible environmental risk factors such as the presence of dogs, water sources, and traditional wooden houses require further investigation.


Assuntos
Doenças Endêmicas , Leishmaniose Cutânea/epidemiologia , Pele/parasitologia , Adolescente , Adulto , Idoso , Biópsia , Exposição Ambiental/efeitos adversos , Feminino , Florestas , Guiana Francesa/epidemiologia , Ouro , Humanos , Leishmania braziliensis/isolamento & purificação , Leishmania guyanensis/isolamento & purificação , Leishmania mexicana/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Mineração/estatística & dados numéricos , Fatores de Risco , Adulto Jovem
8.
Am J Trop Med Hyg ; 101(4): 780-788, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31407656

RESUMO

American tegumentary leishmaniasis is an endemic anthropozoonosis undergoing expansion on the American continent. The disease is caused by several Leishmania species and it is manifested as cutaneous and mucocutaneous leishmaniasis. In this study, we evaluate the viability of high-resolution melt polymerase chain reaction (HRM-PCR) analysis to differentiate four closely related Leishmania species as a routine tool for the diagnosis of leishmaniasis. For this purpose, biopsy specimens from cutaneous and mucocutaneous lesions were taken from 132 individuals from endemic and non-endemic areas for leishmaniasis. Each sample was processed for parasitological, histopathological, and molecular analysis. Positive biopsy samples were analyzed by HRM-PCR of a 144-bp heat-shock protein (hsp70) gene fragment, and new cases were confirmed by sequencing. Of the 132 samples analyzed, 36 (27%) were positive for Leishmania spp., of which 86% were from cutaneous lesions and 14% from mucocutaneous lesions. We identified Leishmania (Viannia) braziliensis (84%), Leishmania (Leishmania) infantum (13%), and Leishmania (Leishmania) amazonensis (3%) in cutaneous lesions, and L. (V.) braziliensis (40%), L. (L.) infantum (20%), L. (L.) amazonensis (20%), and Leishmania (Viannia) guyanensis (20%) in mucocutaneous lesions. The main purpose of this research was to report for the first time in Paraguay the presence of L. (L.) amazonensis and L. (V.) guyanensis in patients with cutaneous and mucocutaneous lesions, using the HRM-PCR technique. In addition, we report the presence of additional new cases of L. (L.) infantum in cutaneous lesions.


Assuntos
Leishmania braziliensis/isolamento & purificação , Leishmania guyanensis/isolamento & purificação , Leishmania infantum/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Mucocutânea/epidemiologia , Adulto , Idoso , Feminino , Geografia , Humanos , Leishmania braziliensis/genética , Leishmania guyanensis/genética , Leishmania infantum/genética , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Leishmaniose Mucocutânea/parasitologia , Leishmaniose Mucocutânea/patologia , Masculino , Pessoa de Meia-Idade , Paraguai/epidemiologia , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA , Pele/parasitologia , Pele/patologia
9.
PLoS Negl Trop Dis ; 13(6): e0007382, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31170148

RESUMO

Leishmania braziliensis, the main etiological agent of cutaneous leishmaniasis (CL) in Latin America, is characterized by major differences in basic biology in comparison with better-known Leishmania species. It is also associated with a high phenotypic and possibly genetic diversity that need to be more adequately defined. Here we used whole genome sequences to evaluate the genetic diversity of ten L. braziliensis isolates from a CL endemic area from Northeastern Brazil, previously classified by Multi Locus Enzyme Electrophoresis (MLEE) into ten distinct zymodemes. These sequences were first mapped using the L. braziliensis M2904 reference genome followed by identification of Single Nucleotide Polymorphisms (SNPs). A substantial level of diversity was observed when compared with the reference genome, with SNP counts ranging from ~95,000 to ~131,000 for the different isolates. When the genome data was used to infer relationship between isolates, those belonging to zymodemes Z72/Z75, recovered from forested environments, were found to cluster separately from the others, generally associated with more urban environments. Among the remaining isolates, those from zymodemes Z74/Z106 were also found to form a separate group. Phylogenetic analyses were also performed using Multi-Locus Sequence Analysis from genes coding for four metabolic enzymes used for MLEE as well as the gene sequence coding for the Hsp70 heat shock protein. All 10 isolates were firmly identified as L. braziliensis, including the zymodeme Z26 isolate previously classified as Leishmania shawi, with the clustering into three groups confirmed. Aneuploidy was also investigated but found in general restricted to chromosome 31, with a single isolate, from zymodeme Z27, characterized by extra copies for other chromosomes. Noteworthy, both Z72 and Z75 isolates are characterized by a much reduced heterozygosity. Our data is consistent with the existence of distinct evolutionary groups in the restricted area sampled and a substantial genetic diversity within L. braziliensis.


Assuntos
Ecótipo , Variação Genética , Leishmania braziliensis/classificação , Leishmania braziliensis/genética , Leishmaniose Cutânea/parasitologia , Brasil , Humanos , Leishmania braziliensis/isolamento & purificação , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
11.
Parasite Immunol ; 41(5): e12620, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30815888

RESUMO

AIMS: The polymorphism observed in Leishmania braziliensis is associated with different clinical forms of leishmaniasis. Neutrophils (PMNs) participate in the pathogenesis of leishmania infection, and here, we evaluate neutrophil function after infection with isolates of L. braziliensis from cutaneous leishmaniasis (CL) or disseminated leishmaniasis (DL) patients. METHODS AND RESULTS: Neutrophils from 30 healthy subjects (HS) were infected with isolates of L. (V.) braziliensis obtained from three CL and three DL patients. They were infected at the ratio of 3:1 parasites per neutrophil, and leishmania uptake was evaluated by microscopy. The neutrophil activation markers and oxidative burst by expression of dihidrorhodamine (DHR) were evaluated by flow cytometry and cytokine production by ELISA. The frequency of infected cells and the number of amastigotes were higher in neutrophils infected with CL isolates compared to DL isolates (P < 0.05). The DHR and CD66b expression after infection with DL isolate was lower than with CL isolates. There was no difference regarding chemokine production. CONCLUSION: The L. (V.) braziliensis isolates of DL induced lower respiratory burst and neutrophils activation markers compared with CL isolates which may contribute to parasite survival and dissemination in DL patients.


Assuntos
Antígenos CD/metabolismo , Moléculas de Adesão Celular/metabolismo , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/imunologia , Adolescente , Adulto , Animais , Feminino , Proteínas Ligadas por GPI/metabolismo , Humanos , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Masculino , Ativação de Neutrófilo , Neutrófilos/imunologia , Adulto Jovem
12.
Emerg Infect Dis ; 25(4): 642-648, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30882319

RESUMO

Mucosal leishmaniasis (ML) is a complication of New World cutaneous leishmaniasis (CL) caused mainly by Leishmania (Viannia) braziliensis. This retrospective study investigated all cases of ML caused by L. (V.) braziliensis in a tertiary medical center in Israel, evaluating the risk factors, clinical presentations, diagnosis, treatment, and outcome of mucosal involvement in ML caused by L. (V.) braziliensis in travelers returning to Israel. During 1993-2015, a total of 145 New World CL cases were seen in travelers returning from Bolivia; among them, 17 (11.7%) developed ML. Nasopharyngeal symptoms developed 0-3 years (median 8 months) after exposure. The only significant risk factor for developing ML was the absence of previous systemic treatment. Among untreated patients, 41% developed ML, compared with only 3% of treated patients (p = 0.005). Systemic treatment for CL seems to be a protective factor against developing ML.


Assuntos
Doenças Transmissíveis Importadas , Leishmania braziliensis , Leishmaniose Mucocutânea/transmissão , Adulto , Bolívia , Doenças Transmissíveis Importadas/prevenção & controle , Doenças Transmissíveis Importadas/transmissão , Diagnóstico Diferencial , Feminino , Humanos , Israel , Leishmania braziliensis/isolamento & purificação , Leishmaniose Mucocutânea/diagnóstico , Leishmaniose Mucocutânea/prevenção & controle , Leishmaniose Mucocutânea/terapia , Masculino , Patologia Molecular , Estudos Retrospectivos , Fatores de Risco , Dermatopatias Parasitárias , Doença Relacionada a Viagens
13.
Parasitol Res ; 118(1): 317-324, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30397777

RESUMO

A skin test is a widely used tool in diagnostic evaluations to investigate cutaneous leishmaniases (CL). The actual antigen (Montenegro skin test [MST] antigen) presents some difficulties that pertain to its manufacturing and validation. To contribute to overcoming this problem, we propose the application of new-generation molecules that are based on skin antigen tests. These antigens were obtained through biotechnology pathways by manufacturing synthetic mimetic peptides. Three peptides, which were selected by phage display, were tested as skin test antigens in an animal model (Cavia porcellus) that was immunized with Leishmania amazonensis or Leishmania braziliensis. The peptide antigens, individually (PA1, PA2, PA3) or in a mix (PAMix), promoted induration reactions at 48 and 72 h after the test was performed. The indurations varied from 0.5 to 0.7 cm. In the animals immunized with L. amazonensis, the PA3 antigen showed better results than the standard MST antigen. In animals immunized with L. braziliensis, two peptide antigens (PA2 and PAMix) promoted induration reactions for a longer period of time than the standard MST antigen. These results validate our hypothesis that peptides could be used as antigens in skin tests and may replace the current antigen for CL diagnosis.


Assuntos
Antígenos de Protozoários/imunologia , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/diagnóstico , Peptídeos/imunologia , Testes Cutâneos/métodos , Animais , Modelos Animais de Doenças , Cobaias , Humanos , Leishmania/imunologia , Leishmania braziliensis/genética , Leishmania braziliensis/isolamento & purificação , Leishmania mexicana/imunologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia
14.
Mem Inst Oswaldo Cruz ; 113(12): e180323, 2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30540021

RESUMO

BACKGROUND The transmission routes for American cutaneous leishmaniasis (ACL) are in flux, so studies examining its transmission in humans, mammalian hosts, and sand fly vectors are urgently needed. OBJECTIVES The aim of this work was understand the epidemiological cycles of Leishmania spp., which causes ACL in the Andean Region of Venezuela, by identifying the Leishmania and the sand fly species involved in human and dog infections. METHODS Thirty-one biopsies from patients in Mérida and Táchira states with suspected ACL were studied by both parasitological tests (cultures and hamster inoculation) and a molecular test [Internal transcribed spacer 1 (ITS1) nested polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)]. We also conducted a survey to detect Leishmania infection in dogs (Immunifluorescence antibody test and ITS1 nested PCR-RFLP) and sand flies (ITS1 nested PCR-RFLP) from El Carrizal, a highly endemic focus of ACL in Venezuela. FINDINGS Three different Leishmania species were identified in the clinical samples from humans (Leishmania braziliensis, L. guyanensis, and L. mexicana) and dogs (L. guyanensis and L. mexicana). The predominant sand fly species found were those from the Verrucarum group (infected with L. mexicana) and Lutzomyia migonei (infected with L. guyanensis and L. mexicana). MAIN CONCLUSIONS We show that Lu. migonei may be the putative vector in two ACL epidemiological cycles, involving L. guyanensis and L. mexicana. We also report for the first time the presence of L. guyanensis in domestic animals.


Assuntos
DNA Espaçador Ribossômico/genética , Insetos Vetores/parasitologia , Leishmania braziliensis/genética , Leishmania guyanensis/genética , Leishmania mexicana/genética , Leishmaniose Cutânea/parasitologia , Psychodidae/parasitologia , Animais , Cães , Feminino , Humanos , Leishmania braziliensis/isolamento & purificação , Leishmania guyanensis/isolamento & purificação , Leishmania mexicana/isolamento & purificação , Leishmaniose Cutânea/transmissão , Tipagem Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Venezuela
15.
Artigo em Inglês | MEDLINE | ID: mdl-30333964

RESUMO

Introduction: In cutaneous leishmaniasis, the host immune response is responsible for the development of skin injuries but also for resolution of the disease especially after antileishmanial therapy. The immune factors that participate in the regulation of inflammation, remodeling of the extracellular matrix, cell proliferation and differentiation may constitute biomarkers of diseases or response to treatment. In this work, we analyzed the production of the growth factors EGF, TGFß1, PDGF, and FGF during the infection by Leishmania parasites, the development of the injuries and the early response to treatment. Methodology: Golden hamsters were infected with L. (V) braziliensis. The growth factors were detected in skin scrapings and biopsies every 2 weeks after infected and then at day 7 of treatment with different drug candidates by RT-qPCR. The parasitic load was also quantified by RT-qPCR in skin biopsies sampled at the end of the study. Results: The infection by L. (V) braziliensis induced the expression of all the growth factors at day 15 of infection. One month after infection, EGF and TGFß1 were expressed in all hamsters with inverse ratio. While the EGF and FGF levels decreased between day 15 and 30 of infection, the TGFß1 increased and the PGDF levels did not change. The relative expression of EGF and TGFß1 increased notably after treatment. However, the increase of EGF was associated with clinical cure while the increase of TGFß1 was associated with failure to treatment. The amount of parasites in the cutaneous lesion at the end of the study decreased according to the clinical outcome, being lower in the group of cured hamsters and higher in the group of hamsters that had a failure to the treatment. Conclusions: A differential profile of growth factor expression occurred during the infection and response to treatment. Higher induction of TGFß1 was associated with active disease while the higher levels of EGF are associated with adequate response to treatment. The inversely EGF/TGFß1 ratio may be an effective biomarker to identify establishment of Leishmania infection and early therapeutic response, respectively. However, further studies are needed to validate the utility of the proposed biomarkers in field conditions.


Assuntos
Antiprotozoários/uso terapêutico , Biomarcadores/análise , Monitoramento de Medicamentos/métodos , Fator de Crescimento Epidérmico/análise , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/patologia , Fator de Crescimento Transformador beta1/análise , Animais , Biópsia , Modelos Animais de Doenças , Fatores de Crescimento de Fibroblastos/análise , Perfilação da Expressão Gênica , Leishmania braziliensis/isolamento & purificação , Mesocricetus , Carga Parasitária , Fator de Crescimento Derivado de Plaquetas/análise , Reação em Cadeia da Polimerase em Tempo Real , Pele/patologia
16.
Biomed Pharmacother ; 108: 1170-1180, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30372818

RESUMO

Leishmania (Viannia) braziliensis is the most common etiological agent of cutaneous and mucocutaneous leishmaniasis (MCL) in Latin America. An interesting aspect of the disease outcome caused by this species is the appearance of non-ulcerated atypical cutaneous leishmaniasis. Atypical (AT) lesions are often associated with therapeutic failure when treated with antimony(Sb)-based drugs. Refractory cases are not necessarily due to intrinsic parasite drug resistance. The status of in vitro drug susceptibility from L. braziliensis field isolates is less assessed than patient treatment outcome. In this work, L. braziliensis isolated from typical CL (6), MCL (1) and AT (3) lesions and vector (1) were tested for their susceptibility to amphotericin B (AmB), miltefosine (MIL), glucantime (GLU) and non-comercial meglumine antimoniate (MA). Overall, intracellular amastigotes of all isolates were sensitive to the tested antileishmanial drugs except AT lesions-derived strains 316, 330 and 340 that presented in vitro resistance against SbV-based drugs. Although susceptible to miltefosine - based on phenotypic screening - intramacrophagic quiescent amastigotes could restore infection. L. braziliensis promastigotes isolated from AT lesions also displayed 29% reduced capacity to infect human monocyte-derived macrophages when compared with parasites obtained from patients with typical lesions, MCL or from sand-fly. These data indicate differences in drug susceptibility and infectiveness among L. braziliensis isolated from patients exhibiting different types of lesions and highlight the importance of its characterization for drug response prediction outcome in clinical practice.


Assuntos
Antimônio/farmacologia , Antiprotozoários/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Leishmania braziliensis/efeitos dos fármacos , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Anfotericina B/farmacologia , Humanos , Especificidade da Espécie , Células THP-1
17.
Free Radic Biol Med ; 129: 35-45, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30196081

RESUMO

Human leishmaniasis caused by Leishmania (Viannia) braziliensis can be presented as localized cutaneous leishmaniasis (LCL) or mucosal leishmaniasis (ML). Macrophages kill parasites using nitric oxide (NO) and reactive oxygen species (ROS). The aim of this study was to evaluate the ability of parasites obtained from patients with LCL or ML to produce and resist NO or ROS. Promastigotes and amastigotes from LCL or ML isolates produced similar amounts of NO in culture. Promastigotes from ML isolates were more resistant to NO and H2O2 than LCL parasites in a stationary phase, whereas amastigotes from LCL isolates were more resistant to NO. In addition, in the stationary phase, promastigote isolates from patients with ML expressed more thiol-specific antioxidant protein (TSA) than LCL isolates. Therefore it is suggested that infective promastigotes from ML isolates are more resistant to microbicidal mechanisms in the initial phase of infection. Subsequently, amastigotes lose this resistance. This behavior of ML parasites can decrease the number of parasites capable of stimulating the host immune response shortly after the infection establishment.


Assuntos
Antiprotozoários/farmacologia , Peróxido de Hidrogênio/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Óxido Nítrico/farmacologia , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Meios de Cultura/química , Feminino , Interações Hospedeiro-Parasita , Humanos , Imunidade Inata , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania braziliensis/isolamento & purificação , Leishmania braziliensis/metabolismo , Leishmaniose Tegumentar Difusa/imunologia , Leishmaniose Tegumentar Difusa/metabolismo , Leishmaniose Tegumentar Difusa/parasitologia , Leishmaniose Mucocutânea/imunologia , Leishmaniose Mucocutânea/metabolismo , Leishmaniose Mucocutânea/parasitologia , Estágios do Ciclo de Vida/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Nitroprussiato/farmacologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
18.
Acta Trop ; 187: 144-150, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30063885

RESUMO

Lutzomyia migonei is incriminated as a vector of Leishmania braziliensis, the main causative agent of cutaneous leishmaniasis in Brazil. Recently, this phlebotomine sand fly species has been suggested as a vector for Leishmania infantum, which causes zoonotic visceral leishmaniasis. Considering the widespread distribution of Lu. migonei in South America, the existence of isolated populations has been hypothesized. Three Lu. migonei populations, two from north-eastern Brazil (Machados, Pernambuco State, and Baturité, Ceará State) and other from the south-eastern region (Niterói, Rio de Janeiro State) were analysed both morphologically and genetically. Though no significant morphological differences were found amongst the sand fly specimens analysed, discriminant analysis based on specific morphometric characters (i.e., length of wing, antennal segment 3 and coxite for males, and length of wing and antennal segment 3 for females), showed that specimens from Machados were closer to Baturité than to Niterói. The molecular analysis of cytochrome c oxidase subunit I gene sequences also supported this observation by the distinct separation of two monophyletic clades, grouping specimens from Machados and Baturité separately from those of Niterói. Our results suggest the existence of different populations within the distribution range of Lu. migonei. Whether these populations are reproductively isolated and/or present differences in terms of vector competence/capacity for L. braziliensis and L. infantum needs to be further investigated.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Insetos Vetores/genética , Filogenia , Psychodidae/genética , Animais , Antenas de Artrópodes/anatomia & histologia , Brasil , Feminino , Insetos Vetores/anatomia & histologia , Insetos Vetores/parasitologia , Leishmania braziliensis/isolamento & purificação , Leishmania infantum/isolamento & purificação , Leishmaniose Cutânea/transmissão , Leishmaniose Visceral/transmissão , Masculino , Tamanho do Órgão , Psychodidae/anatomia & histologia , Psychodidae/parasitologia , Asas de Animais/anatomia & histologia
19.
Parasitol Res ; 117(10): 3157-3168, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30022292

RESUMO

A variety of clinical forms of American cutaneous leishmaniasis (ACL) caused by Leishmania braziliensis, as well as differing immune responses of patients, have been reported for an ACL focus in the state of Minas Gerais, Brazil. In addition, two genetic profiles of L. braziliensis have been described, of which one variant profile (hsp70-variant) has been associated with atypical lesions. We investigated the biological behavior of genetic variant strains of L. braziliensis isolated from patients with different clinical manifestations of ACL. Experimental infections were performed with golden hamsters for five L. braziliensis strains in standardized doses of 1 × 106 parasites per inocula. The characteristics of skin lesions, histopathological features, and parasite burden were independently analyzed at 30 and 60 days post-infection. The data revealed distinct patterns in the onset time of visible skin lesions as well as in lesion size and parasite burden among the strains. The extent and density of the inflammatory infiltrate differed among strains, although cellular composition of granulomas appeared similar. Multivariate analysis indicated the occurrence of two clusters: one comprising native strains (cluster 1) and one comprising the reference strain (cluster 2). Within cluster 1, the genetic variants of L. braziliensis did not group with the non-variant strain suggesting that the distinct patterns of biological behavior of these strains could be associated with the known genetic diversity previously described for them.


Assuntos
Variação Genética/genética , Leishmania braziliensis/genética , Leishmaniose Cutânea/patologia , Pele/patologia , Adulto , Animais , Brasil/epidemiologia , Cricetinae , Proteínas de Choque Térmico HSP70/genética , Humanos , Leishmania braziliensis/classificação , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Masculino , Mesocricetus/parasitologia , Pele/parasitologia
20.
Am J Trop Med Hyg ; 99(2): 327-330, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29869609

RESUMO

Mucosal leishmaniasis (ML) is associated with progressive tissue destruction and granuloma formation, often after a considerable period of latency from an initial cutaneous infection. We report a case of recurrent epistaxis of 3 years duration and nasopharyngeal obstruction in a woman with treated cutaneous leishmaniasis nearly 30 years before and with no further exposure to Leishmania. Computed tomography revealed nasal septal perforation and histopathology demonstrated chronic inflammation. Microscopy was negative for amastigotes, but molecular testing of nasal mucosa biopsy detected Leishmania (Viannia) braziliensis. The patient underwent 28 days of treatment with IV sodium stibogluconate and her symptoms improved significantly. Sixteen months after treatment, she continues to have episodic epistaxis and detectable parasite load in her nasal lesion. Although ML is known to take years to decades to develop, there are few reported cases in the literature of such a long latency period. This report highlights the importance of considering ML in the differential diagnosis of chronic epistaxis in countries where leishmaniasis is endemic or in immigrants from these countries, even when presentation occurs decades after leaving an endemic region.


Assuntos
Leishmaniose Mucocutânea/complicações , Leishmaniose Mucocutânea/diagnóstico , Mucosa Nasal/parasitologia , Perfuração do Septo Nasal/parasitologia , Adulto , Gluconato de Antimônio e Sódio/uso terapêutico , Antiprotozoários/uso terapêutico , Diagnóstico Diferencial , Epistaxe/parasitologia , Feminino , Humanos , Inflamação , Leishmania braziliensis/genética , Leishmania braziliensis/isolamento & purificação , Leishmaniose Mucocutânea/tratamento farmacológico , Perfuração do Septo Nasal/diagnóstico por imagem , Septo Nasal/diagnóstico por imagem , Septo Nasal/patologia , Carga Parasitária , Peru , Fatores de Tempo , Tomografia Computadorizada por Raios X
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