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1.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 59: e190524, fev. 2022. tab
Article in English | LILACS, VETINDEX | ID: biblio-1380228

ABSTRACT

Leishmaniases comprise a spectrum of diseases caused by protozoan parasites of the genus Leishmania, with some species of rodents being incriminated as reservoirs. The capybara is the largest extant rodent species in the world and is widely distributed in South America. The occurrence of infection by Leishmania spp. was investigated in capybaras captured in Brazil during 2015­2019 from established populations in five highly anthropic areas of the state of São Paulo and two natural areas of the states of Mato Grosso and Mato Grosso do Sul. A total of 186 individuals were captured and subjected to abdominal skin biopsy. All skin samples were Leishmania kDNA-negative, suggesting that capybaras have no role in the transmission cycles of Leishmania species in the studied areas despite the well-known role of other rodents in the life cycle of Leishmania spp.(AU)


As leishmanioses compreendem um espectro de doenças causadas por protozoários do gênero Leishmania e algumas espécies de roedores são incriminadas como reservatórios de Leishmania spp. As capivaras compreendem a maior espécie de roedores existentes e são amplamente distribuídas na América do Sul. Para investigar a ocorrência de infecção por Leishmania spp. em capivaras, durante os anos de 2015-2019 capivaras foram capturadas em cinco áreas antrópicas do estado de São Paulo e em duas áreas naturais dos estados do Mato Grosso e do Mato Grosso do Sul, todos esses ambientes com populações de capivaras estabelecidas. Um total de 186 indivíduos foram capturados e submetidos à biópsia de pele abdominal. Todas as amostras de pele foram negativas para o alvo kDNA, assim, os dados sugerem que nas áreas estudadas as capivaras não têm papel no ciclo de transmissão de espécies de Leishmania spp., apesar do papel bem conhecido de outros roedores no ciclo de vida de Leishmania spp.(AU)


Subject(s)
Animals , Protozoan Infections, Animal/diagnosis , Rodentia/microbiology , Leishmaniasis/diagnosis , Skin/microbiology , Biopsy/instrumentation , Brazil , DNA, Kinetoplast/analysis , Leishmania/genetics
2.
Rev. bras. parasitol. vet ; 30(3): e006621, 2021. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1288698

ABSTRACT

Abstract The aim of this study was to investigate the level of exposure to Leishmania infection in stray dogs in an area of intense visceral leishmaniasis transmission in the state of Pernambuco, Brazil. Blood samples from 178 dogs were analyzed using serological and molecular assays: rapid immunochromatographic test (ICT), enzyme-linked immunosorbent assay (ELISA), immunofluorescence antibody test (IFAT), and conventional and quantitative polymerase chain reaction (cPCR and qPCR). Positivity values obtained with serological tests were 71.4% (127/178), 70.2% (125/178), and 50.6% (90/178) using ICT, ELISA, and IFAT, respectively, with 38.8% (69/178) of the dogs were simultaneously positive for all three tests. The positivity values obtained with cPCR and qPCR were 20.2% (36/178) and 38.8% (69/178), respectively, with 11.8% (21/178) testing positive in both molecular assays. Overall, 87.1% (155/178) were positive for anti-Leishmania spp. antibodies and/or Leishmania spp. DNA. Positivity to one or more tests was statistically associated with lymphadenomegaly, skin lesions, lymphocytosis, anemia and hyperproteinemia. The results of this study revealed a high level of exposure to Leishmania in stray dogs in an area of intense human visceral leishmaniasis transmission, suggesting that dogs play a role as reservoirs in the transmission cycle of this zoonosis.


Resumo O objetivo deste estudo foi investigar o nível de exposição à infecção por Leishmania em cães errantes de uma área de transmissão intensa de leishmaniose visceral no estado de Pernambuco. Amostras de sangue de 178 cães foram avaliadas por testes sorológicos e moleculares: teste imunocromatográfico (IC), ensaio imunoenzimático (ELISA), teste de imunofluorescência de anticorpos (RIFI), reação em cadeia da polimerase convencional e quantitativa (cPCR e qPCR). Os valores de positividade obtidos com os testes sorológicos foram 71,4% (127/178), 70,2% (125/178) e 50,6% (90/178) com IC, ELISA e RIFI, respectivamente. E com 38,8% (69/178) dos cães mostraram-se simultaneamente positivos aos três testes. Os valores de positividade obtidos por cPCR e qPCR foram 20,2% (36/178) e 38,8% (69/178), respectivamente. E com 11,8% (21/178) dos cães foram positivos em ambos os testes moleculares. No geral, 87,1% (155/178) foram positivos para anticorpos anti-Leishmania spp. e/ou material genético de Leishmania spp. A positividade a um ou mais testes foi estatisticamente associada à linfonodomegalia, lesões cutâneas, linfocitose, anemia e hiperproteinemia. Os resultados do estudo revelam um alto nível de exposição à Leishmania spp. em cães errantes em uma área de transmissão intensa de leishmaniose visceral humana, sugerindo que eles podem desempenhar um papel como reservatórios no ciclo de transmissão dessa zoonose.


Subject(s)
Humans , Animals , Dogs , Leishmaniasis/veterinary , Leishmania infantum/genetics , Dog Diseases/diagnosis , Dog Diseases/epidemiology , Leishmania/genetics , Leishmaniasis, Visceral/diagnosis , Brazil/epidemiology , Enzyme-Linked Immunosorbent Assay/veterinary , Leishmaniasis, Visceral/veterinary , Leishmaniasis, Visceral/epidemiology
3.
Rev. bras. parasitol. vet ; 30(3): e009121, 2021.
Article in English | LILACS, VETINDEX | ID: biblio-1288705

ABSTRACT

Abstract The dog is the main domestic reservoir of Leishmania and font of infection for the vector, constituting an important host for the transmission of the parasite to humans. Non-invasive collection of swab samples for leishmaniasis diagnosis has been a promising alternative. This study analyzed the positivity of polymerase chain reaction (PCR) for the diagnosis of canine leishmaniasis in conjunctiva samples. DNA extraction was performed using SDS 20% and PCR was performed using 13A/13B primers that amplify 120-bp of Leishmania kDNA. Of the 77 dogs analyzed, 50 (64.93%) had ocular changes: 25 (32.47%) dogs had periocular lesion, 41 (53.25%) dogs had purulent eye discharge, and 17 (22.08%) dogs had both signals. PCR was positive in 35 dogs (45.45%), and there was no significant difference between dogs with and without ocular signals (p=0.4074). PCR positivity was significant higher in dogs without periocular injury (p=0.0018). Conjunctive PCR, a less invasive, fast, and painless collection technique, is indicated to complement the diagnosis, especially in dogs without periocular injury, independent of the presence of purulent eye discharge.


Resumo O cão é o principal reservatório doméstico de Leishmania e também fonte de infecção para o vetor, constituindo um importante hospedeiro para a transmissão do parasita ao homem. A coleta não invasiva de amostras em swab para diagnóstico das leishmanioses tem sido uma alternativa promissora. Este estudo analisou a positividade da reação em cadeia da polimerase (PCR) para o diagnóstico de leishmaniose canina em amostras de conjuntiva. A extração do DNA foi realizada com SDS 20%. A PCR foi realizada com primers 13A/13B que amplificam 120-pb do kDNA de Leishmania. Dos 77 cães analisados, 50 (64,93%) tiveram alterações oculares; 25 (32,47%) cães tiveram uma lesão periocular; 41 (53,25%) tiveram secreção ocular purulenta e 17 (22,08%) cães tiveram ambos os sinais. A PCR foi positiva em 35 cães (45,45%) e não houve diferença significativa em cães com e sem sinais oculares (p = 0,4074). A positividade da PCR foi significativamente maior em cães sem lesão periocular (p = 0,0018). PCR em conjuntiva, uma técnica de coleta menos invasiva, rápida e indolor, é indicada para complementar o diagnóstico, principalmente em cães sem lesão periocular, independentemente da presença de secreção ocular purulenta.


Subject(s)
Animals , Dogs , Leishmania infantum/genetics , Dog Diseases/diagnosis , Leishmania/genetics , Leishmaniasis, Visceral/veterinary , DNA , Polymerase Chain Reaction/veterinary , DNA, Protozoan/genetics , Conjunctiva
4.
Mem. Inst. Oswaldo Cruz ; 116: e200572, 2021. tab, graf
Article in English | LILACS | ID: biblio-1287341

ABSTRACT

BACKGROUND The genetic heterogeneity of Leishmania parasites is a major factor responsible for the wide variety of Leishmania-associated manifestations. Consequently, understanding the genetic make-up of Leishmania species using suitable molecular markers is an important component of realising local and regional scale disease risk. The cytochrome b (cytb) is frequently used to type New World Leishmania species. However, its potential to discriminate Leishmania species and variants requires further evaluation. OBJECTIVES To explore the capacity of cytb gene to identify New World Leishmania species and variants and to develop an approach able to type local Leishmania species and variants. METHODS We retrieved 360 partial and complete Leishmania cytb gene sequences publicly available in GenBank database to study all single nucleotide polymorphisms (SNPs) across the cytb gene that differentiate New World Leishmania species. This information was used to develop an approach based upon the polymorphisms found in a DNA segment of 948bp. We also compared the typing results found with this technique with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) profiling obtained using HSP70 gene as target. One hundred Panamanian isolates were used to both typed Leishmania species and assess local genetic variability. FINDINGS We found complete agreement between our cytb approach and the PCR-RFLP profiling method based on HSP70 for Leishmania species identification. Ninety-two isolates were identified as L. panamensis, although other Viannia species were found circulating at a lower frequency. Three L. panamensis haplotypes were identified in Panamanian provinces. We also provide an initial report of L. guyanensis haplotypes circulating in Panama. MAIN CONCLUSIONS Cytb gene sequence encompasses key main SNPs that aid to identify Leishmania species. The cytb approach developed with this information was able to identify and assess genetic variability of local Leishmania species found in this study.


Subject(s)
Humans , Leishmaniasis, Cutaneous , Leishmania/genetics , Panama , Polymorphism, Restriction Fragment Length , Polymerase Chain Reaction , DNA, Protozoan/genetics , Cytochromes b/genetics
5.
Rev. bras. parasitol. vet ; 30(2): e027920, 2021. tab, graf
Article in English | LILACS | ID: biblio-1251376

ABSTRACT

Abstract The present study aimed to evaluate a methodology for active surveillance of visceral leishmaniasis by detecting Leishmania DNA in organs of wild road-killed animals from November 2016 to October 2018 in the North of Paraná, Brazil. The collection points of road-killed wild animals were georeferenced. The animals were autopsied and samples of bone marrow, lymph node, liver, spleen, and ear skin were collected. Genomic DNA was extracted and subjected to PCR for amplification of Leishmania spp. 18S, kinetoplastic DNA (kDNA), HSP70, and ITS1 genes, and DNA sequencing was performed. The primers used for the amplification of kDNA, ITS1, and HSP70 genes presented non-specific results. Of the 66 mammals collected from 24 different municipalities, one Southern Tamandua (Tamandua tetradactyla) presented DNA of Leishmania spp. in lymph nodes by 18S PCR. DNA sequencing confirmed the results of the subgenus, Viannia, identification. We suggest using the methodology showed in the present study in the active and early surveillance of visceral leishmaniasis in a non-endemic area.


Resumo O objetivo do presente estudo foi avaliar uma metodologia de vigilância ativa da leishmaniose visceral por meio da detecção de DNA de Leishmania em órgãos de animais silvestres atropelados, de novembro de 2016 a outubro de 2018, no Norte do Paraná, Brasil. Os pontos de coleta dos animais silvestres atropelados foram georreferenciados. Os animais foram autopsiados e amostras de medula óssea, linfonodo, fígado, baço, e pele de orelha foram coletados. DNA genômico foi extraído e submetido à PCR para amplificação de quatro diferentes regiões de Leishmania spp.: 18S, kDNA, HSP70 e ITS1, sequenciamento de DNA foi realizado. Os iniciadores utilizados para a amplificação dos genes kDNA, ITS1 e HSP70 apresentaram resultados inespecíficos. Dos 66 mamíferos coletados em 24 diferentes municípios, um tamanduá-mirim (Tamandua tetradactyla) apresentou DNA de Leishmania spp. em linfonodo na PCR, que amplificou o gene 18S. O sequenciamento de DNA confirmou o resultado e demonstrou a presença do subgênero Viannia. Sugere-se o uso da metodologia apresentada no presente estudo na vigilância ativa e precoce da leishmaniose visceral em área não endêmica.


Subject(s)
Animals , Leishmaniasis/diagnosis , Leishmaniasis/veterinary , Leishmaniasis/epidemiology , Leishmania/genetics , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiology , Brazil , Polymerase Chain Reaction/veterinary , Leishmaniasis, Visceral/veterinary , Mammals
6.
Mem. Inst. Oswaldo Cruz ; 116: e200634, 2021. graf
Article in English | LILACS | ID: biblio-1154876

ABSTRACT

The availability of Trypanosomatid genomic data in public databases has opened myriad experimental possibilities that have contributed to a more comprehensive understanding of the biology of these parasites and their interactions with hosts. In this review, after brief remarks on the history of the Trypanosoma cruzi and Leishmania genome initiatives, we present an overview of the relevant contributions of genomics, transcriptomics and functional genomics, discussing the primary obstacles, challenges, relevant achievements and future perspectives of these technologies.


Subject(s)
Trypanosoma cruzi/genetics , Genome, Protozoan/genetics , Leishmania/genetics , Computational Biology , Genomics
7.
Rev. bras. parasitol. vet ; 30(1): e022020, 2021. tab
Article in English | LILACS | ID: biblio-1156230

ABSTRACT

Abstract Leishmaniasis is a zoonotic disease caused by over 20 species of protozoan parasites of the genus Leishmania. Infection is commonly spread by sandflies and produces a wide spectrum of clinical signs and symptoms. Therefore, from an epidemiological and therapeutic standpoint, it is important to detect and differentiate Leishmania spp. The objective of this study was to combinate in silico and in vitro strategies to evaluate the analytical specificity of primers previously described in the literature. According to electronic PCR (e-PCR) analysis, 23 out of 141 pairs of primers selected through literature search matched their previously reported analytical specificity. In vitro evaluation of nine of these primer pairs by quantitative PCR (qPCR) confirmed the analytical specificity of five of them at the level of Leishmania spp., L. mexicana complex or Leishmania and Viannia subgenera. Based on these findings, the combination of e-PCR and qPCR is suggested to be a valuable approach to maximize the specificity of new primer pairs for the laboratory diagnosis of infections with Leishmania spp.


Resumo As leishmanioses são zoonoses causadas por mais de 20 espécies de protozoários do gênero Leishmania. As infecções são comumente disseminadas por flebotomíneos e causam um amplo espectro de manifestações clínicas. Portanto, a detecção e diferenciação de espécies de Leishmania são importantes do ponto de vista epidemiológico e terapêutico. O objetivo deste estudo foi combinar estratégias in silico e in vitro para avaliar a especificidade analítica dos primers descritos anteriormente na literatura. De acordo com a PCR eletrônica (e-PCR), 23 dos 141 pares de primers selecionados por meio de pesquisa da literatura estavam de acordo com a especificidade analítica anteriormente relatada. A avaliação in vitro de nove desses pares de primers, por PCR quantitativa (qPCR), confirmou a especificidade analítica de cinco deles ao nível de espécie de Leishmania, do complexo L. mexicana ou dos subgêneros Leishmania e Viannia. Com base nos resultados, sugere-se que a combinação de e-PCR e qPCR é uma abordagem valiosa para a validação e maximização da especificidade de novos pares de primers para o diagnóstico laboratorial de infecções com Leishmania spp.


Subject(s)
Animals , Psychodidae , Leishmaniasis/veterinary , Leishmania/genetics , Computer Simulation , Leishmaniasis/diagnosis , DNA, Protozoan , Real-Time Polymerase Chain Reaction/veterinary
8.
Rev. peru. med. exp. salud publica ; 37(1): 87-92, ene.-mar. 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1101806

ABSTRACT

RESUMEN En el Perú, la leishmaniasis es una enfermedad metaxénica que representa un serio problema de salud pública, debido a su amplia distribución y al número de personas en riesgo de contraer la enfermedad, siendo la población vulnerable principalmente las personas de bajos recursos económicos. El estudio se realizó a partir de pacientes que fueron derivados al Instituto Nacional de Salud entre el 2006 y el 2011 para que se les realizara el diagnóstico especializado. La identificación de la especie de Leishmania infectante se desarrolló mediante el análisis de las curvas de disociación (HRMA) obtenidas a partir del ADN genómico de promastigotes y amastigotes, lo que permitió identificar las especies de Leishmania (Viannia) braziliensis, Leishmania (V.) guyanensis, Leishmania (V.) peruviana como las más prevalentes, además de Leishmania (V.) lainsoni y Leishmania (L.) amazonensis.


ABSTRACT In Peru, leishmaniasis is a metaxenic disease that represents a serious public health problem, due to its wide distribution and the number of people in danger of contracting the disease, being the vulnerable population mainly those with low economic resources. The study was conducted from patients who were derived to Peru's National Institute of Health between 2006 and 2011 so that the specialized diagnosis could be carried out. The identification of the species of infectious Leishmania was developed through the analysis of the High-Resolution Melting Analysis obtained from the genomic DNA of promastigotes and amastigotes, which allows to identify the species of Leishmania (Viannia) braziliensis, Leishmania (V.) guyanensis, Leishmania (V.) peruviana as more prevalent, in addition to Leishmania (V.) lainsoni and Leishmania (L.) amazonensis.


Subject(s)
Humans , Leishmaniasis , Leishmania , Peru/epidemiology , Leishmania braziliensis/isolation & purification , Leishmania braziliensis/genetics , Leishmaniasis/parasitology , Leishmaniasis/therapy , Leishmaniasis/epidemiology , Leishmania guyanensis/isolation & purification , Leishmania guyanensis/genetics , Leishmania/isolation & purification , Leishmania/genetics
9.
Rev. Soc. Bras. Med. Trop ; 53: e20200006, 2020. tab, graf
Article in English | SES-SP, ColecionaSUS, LILACS | ID: biblio-1136892

ABSTRACT

Abstract INTRODUCTION: We diagnose cases of cutaneous leishmaniasis (CL) among indigenous peoples of the state of Roraima, Brazil, and discuss some aspects of its epidemiology. METHODS: Skin imprints, and lesion exudate samples collected on filter paper were examined using parasitological and molecular techniques, respectively. RESULTS: Of 30 indigenous individuals, representing several ethnic groups, with suspected cases of CL, 27 (90%) tested positive for Leishmania spp. by PCR, and 21 (70%) by parasitological microscopy. CONCLUSIONS: Cutaneous leishmaniasis is indistinctly present among indigenous peoples from different regions of the state of Roraima. Individuals from seven of the ten existing ethnic groups in the state tested positive for CL, demonstrating the need for further investigation of the disease among these ethnic groups.


Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Young Adult , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/epidemiology , Leishmania/genetics , Brazil/epidemiology , Polymerase Chain Reaction , Indigenous Peoples , Middle Aged
10.
Rev. Soc. Bras. Med. Trop ; 53: e20200255, 2020. tab, graf
Article in English | SES-SP, ColecionaSUS, LILACS | ID: biblio-1143862

ABSTRACT

Abstract INTRODUCTION: In the Belém Metropolitan Region (BMR), Pará State, Brazil, American cutaneous leishmaniasis (ACL) is endemic; however, very little is known regarding its causative agents. Therefore, we used our standard diagnostic approach combined with an RNA polymerase II largest subunit (RNAPOIILS)-polymerase chain reaction (PCR) followed by analysis of restriction fragment length polymorphism (PCR-RFLP) to identify Leishmania spp. ACL agents in this region. METHODS: Thirty-two Leishmania spp. isolates from patients with ACL in the BMR during 1995-2018 were analyzed. Leishmania spp. DNA samples were amplified using the primers RPOR2/RPOF2, and the 615-bp PCR products were subjected to enzymatic digestion using TspRI and HgaI endonucleases. RESULTS: ACL etiological agents in the BMR comprised Leishmania (Viannia) lindenbergi (43.7%) followed by Leishmania (Viannia) lainsoni (34.4%), Leishmania (Leishmania) amazonensis (12.5%), and Leishmania (Viannia) braziliensis (9.4%). CONCLUSIONS: To our knowledge, the results of the study revealed for the first time that L. (V.) lindenbergi and L. (V.) lainsoni are the main ACL agents in BMR.


Subject(s)
Humans , Leishmania braziliensis/genetics , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/epidemiology , Leishmania/genetics , United States , Brazil/epidemiology , Leishmaniasis, Cutaneous
11.
Mem. Inst. Oswaldo Cruz ; 115: e200113, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135235

ABSTRACT

BACKGROUND Lutzomyia longipalpis-derived cell line (Lulo) has been suggested as a model for studies of interaction between sandflies and Leishmania. OBJECTIVES Here, we present data of proteomic and gene expression analyses of Lulo cell related to interactions with Leishmania (Viannia) braziliensis. METHODS Lulo cell protein extracts were analysed through a combination of two-dimensional gel electrophoresis and mass spectrometry and resulting spots were further investigated in silico to identify proteins using Mascot search and, afterwards, resulting sequences were applied for analysis with VectorBase. RESULTS Sixty-four spots were identified showing similarities to other proteins registered in the databases and could be classified according to their biological function, such as ion-binding proteins (23%), proteases (14%), cytoskeletal proteins (11%) and interactive membrane proteins (9.5%). Effects of interaction with L. (V.) braziliensis with the expression of three genes (enolase, tubulin and vacuolar transport protein) were observed after an eight-hour timeframe and compared to culture without parasites, and demonstrated the impact of parasite interaction with the expression of the following genes: LLOJ000219 (1.69-fold), LLOJ000326 (1.43-fold) and LLOJ006663 (2.41-fold). CONCLUSIONS This set of results adds relevant information regarding the usefulness of the Lulo cell line for studies with Leishmania parasites that indicate variations of protein expression.


Subject(s)
Animals , Psychodidae/parasitology , Leishmania braziliensis/genetics , Proteomics , Leishmania/genetics , Cell Line , Transcriptome
12.
Mem. Inst. Oswaldo Cruz ; 115: e200157, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135268

ABSTRACT

BACKGROUND In Acre state, Brazil, the dissemination of cutaneous leishmaniasis has increased in recent years, with limited knowledge of the potential Leishmania spp. vectors involved. OBJECTIVES Here, data concerning the sandfly fauna of Brasiléia municipality, Leishmania DNA-detection rates and the identification of blood meal sources of insects captured in 2013-2015 are presented. METHODS Parasite detection in female sandflies was performed individually by multiplex polymerase chain reaction (PCR) (Leishmania kDNA/sandfly cacophony-gene), with the identification of Leishmania spp. by hsp70-PCR and sequencing. The identification of blood gut-content from fed females was performed by cyt b-PCR and sequencing. FINDINGS A total of 4,473 sandflies were captured. A subgroup of 864 non-blood-fed females evaluated for the presence of Leishmania DNA showed 2.9% positivity for Leishmania (Viannia) braziliensis and L. (V.) guyanensis. The identification of blood meal sources was performed in 96 blood-fed females, allowing the identification of 13 vertebrate species. In nine/96 fed females, DNA from L. (V.) shawi, L. (V.) guyanensis, L. (V.) braziliensis and Endotrypanum sp. was detected. MAIN CONCLUSIONS In Brumptomyia sp. and Evandromyia termitophila, the first report of Leishmania DNA-detection is provided in Acre; Nyssomyia shawi is implicated as potential vector of L. (V.) braziliensis and L. (V.) guyanensis for the first time in Brazil.


Subject(s)
Animals , Female , Psychodidae/parasitology , DNA/analysis , Insect Vectors/genetics , Leishmania/genetics , Psychodidae/classification , Brazil , Polymerase Chain Reaction , DNA, Protozoan/analysis , Leishmaniasis, Cutaneous/transmission , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania/isolation & purification
13.
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
14.
Rev. Soc. Bras. Med. Trop ; 53: e20190320, 2020. tab, graf
Article in English | LILACS | ID: biblio-1057289

ABSTRACT

Abstract INTRODUCTION: This study aimed to investigate human exposure to Leishmania spp. infection and sandflies in an area endemic for the disease. METHODS: The presence of antibodies specific for Leishmania spp. and saliva of Lutzomyia spp. and that of L. infantum DNA in blood were evaluated. RESULTS: Antibodies against Leishmania spp. and sandfly saliva were observed in 20.8% and 37.7% of individuals, respectively. DNA of Leishmania spp. was amplified from the blood of one patient. CONCLUSIONS: The results suggest that Leishmania spp. infection may be underdiagnosed in this area.


Subject(s)
Humans , Animals , Male , Female , Adolescent , Adult , Aged , Young Adult , Psychodidae/parasitology , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmaniasis, Visceral/transmission , Brazil , Enzyme-Linked Immunosorbent Assay , Polymerase Chain Reaction , Leishmania/genetics , Leishmania/immunology , Leishmaniasis, Visceral/epidemiology , Middle Aged
15.
Biomédica (Bogotá) ; 39(2): 252-264, ene.-jun. 2019. tab, graf
Article in English | LILACS | ID: biblio-1011438

ABSTRACT

Abstract Introduction: The study of the interaction between the parasite, the vector and the mammalian hosts, including man, allows to understand the behavior of the leishmaniases. Objective: To determine the presence of Lutzomyia species and to detect the Leishmania infection in Didelphis marsupialis in an endemic area for visceral leishmaniasis. Materials and methods: Phlebotomine fauna and individuals of D. marsupialis were collected with CDC and Tomahawk™ traps, respectively. The species of Lutzomyia were identified using the Young and Duncan key (1994). Ear and tail biopsies and blood samples from D. marsupialis were taken to identify the Leishmania species by amplifying a fragment of the gene associated with the 70 kD heat shock protein. Results: Seven Lutzomyia species were identified: Lu. evansi, Lu. gomezi, Lu. panamensis, Lu. dubitans, Lu. cayennensis cayennensis, Lu. rangeliana and Lu. trinidadensis. The first three species have epidemiological importance in Colombia because of their implications in the transmission of the Leishmania parasite. Sixty-five tissue samples from 19 D. marsupialis individuals were negative for Leishmania spp. Conclusions: The presence of the Lutzomyia species that have been identified as vectors for Leishmania inside and around houses in the village of El Bledo, in El Carmen de Bolívar represents a risk of infection. Furthermore, the presence of Lu. panamensis is reported for first time in El Carmen de Bolívar in Colombia. Although the lack of detection of Leishmania spp. in D. marsupialis samples may suggest that D. marsupialis does not play an important role in the transmission cycle of Leishmania in this region, it is necessary to carry out further longitudinal studies to confirm this hypothesis.


Resumen Introducción. El estudio de la interacción entre el parásito, el vector y los huéspedes mamíferos, incluido el hombre, permite entender el comportamiento de la leishmaniasis. Objetivo. Determinar la presencia de especies del género Lutzomyia y detectar la infección por Leishmania spp. en Didelphis marsupialis en un área endémica de leishmaniasis visceral. Materiales y métodos. Se recolectaron flebotomíneos y D. marsupialis con trampas CDC y Tomahawk™, respectivamente. Las especies de Lutzomyia se identificaron usando la clave de Young y Duncan, 1994. Se tomaron biopsias de oreja, cola y muestras de sangre de D. marsupialis para diagnosticar Leishmania spp. mediante la amplificación de un fragmento del gen de la proteína de choque térmico de 70 kD. Resultados. Se identificaron siete especies de Lutzomyia: Lu. evansi, Lu. gomezi, Lu. panamensis, Lu. dubitans, Lu. cayennensis cayennensis, Lu. rangeliana y Lu. trinidadensis. Las tres primeras especies son reconocidas como vectores en el país por estar implicadas en la transmisión de Leishmania spp. En total, 65 muestras de tejidos de oreja, cola y de sangre provenientes de 19 D. marsupialis fueron negativas para Leishmania spp. en la PCR-HSP70. Conclusiones. La presencia de flebotomíneos con importancia epidemiológica en la zona evaluada representa un riesgo de transmisión. Asimismo, Lu. panamensis es reportada por primera vez en El Bledo (Carmen de Bolívar). La ausencia de Leishmania spp. en D. marsupialis podría sugerir que esta especie no tiene un papel importante en el ciclo de transmisión de Leishmania en la vereda El Bledo, por lo que es necesario profundizar en estudios longitudinales para corroborar esta hipótesis.


Subject(s)
Adolescent , Adult , Aged , Animals , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Young Adult , Psychodidae , Disease Reservoirs/parasitology , Didelphis , Insect Vectors , Leishmaniasis, Visceral/epidemiology , Psychodidae/parasitology , Rural Population , Species Specificity , Tail/parasitology , Blood/parasitology , Colombia/epidemiology , HSP70 Heat-Shock Proteins/genetics , Endemic Diseases , Didelphis/parasitology , Ear, External/parasitology , Housing , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmania/classification , Leishmania/genetics , Leishmaniasis, Visceral/transmission
16.
Braz. j. infect. dis ; 23(2): 111-120, Mar.-Apr. 2019. tab
Article in English | LILACS | ID: biblio-1011573

ABSTRACT

ABSTRACT Visceral leishmaniasis is a serious and debilitating infection with high fatality rate in tropical and subtropical countries. As clinical symptoms of visceral leishmaniasis are not so specific, confirmatory diagnostic methods with high sensitivity and specificity are needed. Noninvasive methods have been developed using urine as a clinical sample for visceral leishmaniasis diagnosis. In fact, there is a clear correlation between kidney impairment and Leishmania DNA in urine. However, it has been proved that Leishmania nucleic acid may also be isolated from patients without any sign of renal involvement. Even though urine has become a promissing biological sample, it is still not widely used due to several issues, such as (i) incomprehension of the whole renal pathophysiology process in visceral leishmaniasis, (ii) presence of many amplification inhibitors in urine, and (iii) lack of an efficient urinary DNA extraction method. In this article, we performed a literature review to bring a new perspective for Leishmania DNA isolation in urine.


Subject(s)
Humans , DNA, Protozoan/urine , Leishmania/genetics , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/urine , Polymerase Chain Reaction/methods , Reproducibility of Results , DNA, Protozoan/isolation & purification , Sensitivity and Specificity , Leishmania/isolation & purification
18.
Braz. j. med. biol. res ; 52(9): e8224, 2019. tab, graf
Article in English | LILACS | ID: biblio-1019569

ABSTRACT

Leishmaniasis is a neglected disease that affects a large part of the world population. Knowing the sand fly fauna of a region is of fundamental importance for guiding health surveillance actions related to the prevention and control of leishmaniasis. A total of 86 specimens of sand flies (60 females and 26 males) were collected. Using the classification proposed by Galati (2003), the following species were identified: Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1920), Evandromyia cortelezzi (Brethes, 1923), Ev. sallesi (Galvão & Coutinho, 1939), Nyssomyia whitmani (Atunes & Coutinho, 1939), Psathyromyia lutziana (Costa Lima, 1932), Ev. lenti (Mangabeira, 1938), Brumptomyia sp. (França and Parrot, 1921), and Pressatia sp. (Mangabeira, 1942). Using PCR with internal transcribed spacer target to identify infected sand flies, five Lu. longipalpis females were infected with Leishmania spp. Despite the small number of specimens collected, considerable species diversity was found in the study area.


Subject(s)
Animals , Male , Female , Psychodidae/classification , Psychodidae/parasitology , RNA, Protozoan/genetics , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania/isolation & purification , Brazil , Leishmaniasis/transmission , Polymerase Chain Reaction , DNA, Ribosomal Spacer/genetics , Leishmania/genetics
19.
Salvador; s.n; 2018. 123 p. ilus, tab.
Thesis in Portuguese | LILACS | ID: biblio-1005578

ABSTRACT

INTRODUÇÃO: Macrófagos de camundongos CBA controlam a infecção por Leishmania major, no entanto, são permissivos à infecção por Leishmania amazonensis. Os estudos conduzidos, até o momento, sobre o papel desempenhado pela autofagia na infecção por Leishmania levaram a dados controversos. OBJETIVO: No presente trabalho, avaliamos se a resposta autofágica de macrófagos infectados pode ser responsável pela diferença no curso da infecção por essas duas espécies de Leishmania. MATERIAL e MÉTODOS e RESULTADOS: Inicialmente, demonstramos por qPCR e por análise de dados de microarranjos públicos que um número maior de genes relacionados à autofagia é modulado positivamente em células infectadas por L. amazonensis em comparação às infectadas L. major. Ingenuity Pathway Analysis (IPA) demonstrou modulação oposta dos genes relacionados à autofagia entre os macrófagos infectados com L. amazonensis daqueles infectados com L. major. Após 24 h de infecção, a relação LC3-II/Act é aumentada tanto em macrófagos infectados por L. amazonensis quanto nos infectados por L. major em comparação com controles não infectados, mas menos do que em células tratadas com cloroquina. Embora, os vacúolos parasitóforos induzidos por L. major tenham apresentado maior positividade para o marcador degradativo, DQBSA, o recrutamento de LC3 foi maior nos vacúolos parasitóforos induzidos por L. amazonensis. Interessantemente, tanto a indução farmacológica quanto a fisiológica da autofagia aumentaram a viabilidade intracelular de L. amazonensis e L. major, enquanto a inibição da autofagia não teve efeito sobre a viabilidade intracelular desses parasitas. Também demonstramos que a indução da autofagia reduziu a produção de NO por macrófagos infectados por L. amazonensis ou L. major, mas não alterou a atividade da arginase, A análise de componentes principais e agrupamento hierárquico de clusters discriminaram completamente os macrófagos infectados por L. major de células infectadas por L. amazonensis de acordo com a intensidade da infecção e características autofágicas dos vacúolos induzidos por essas duas cepas. CONCLUSÃO: Em conclusão, a infecção por L. amazonensis ou L. major, apesar de ativar similarmente o fluxo autofágico em macrófagos infectados e os parasitos terem sua viabilidade favorecida pela indução da autofagia, promove expressão diferenciada de genes relacionados à autofagia e interação distinta dos vacúolos parasitóforos com compartimentos autofágicos. Essas diferenças são capazes de separar completamente os macrófagos infectados por L. amazonensis daqueles por L. major


INTRODUCTION: CBA mouse macrophages (MΦ) control Leishmania major infection yet are permissive to Leishmania amazonensis. The role played by autophagy in Leishmania infection needs further investigation. OBJECTIVE: Thus, we assessed whether activation of autophagic pathway may account for differences in the response of infected MΦ to these two parasite strains. MATERIAL and METHODS and RESULTS: First, we demonstrated by qPCR and by analysis of publicly available microarray data that a greater number of autophagy-related genes (Atg) are positively modulated in cells infected by L. amazonensis compared to those infected by L. major. Ingenuity Pathway Analyses (IPA) demonstrated opposite modulation in genes in L. amazonensisand L. major-infected MΦ. After 24 h of infection, the autophagic flux measured by LC3-II/Act ratio was similarly increased in either L. amazonensis- or L. majorinfected MΦ compared to uninfected cells. Although L. major-induced parasitophorous vacuoles exhibited greater positivity for the degradative marker, DQ-BSA, LC3 recruitment was increased in L. amazonensis-induced parasitophorous vacuoles. Interestingly, autophagy induction enhanced intracellular L. amazonensis and L. major viability, although autophagy inhibition caused no effect on infection profile. We also demonstrated that autophagy induction reduced NO production by Leishmania-infected MΦ, yet did not alter arginase activity. Moreover, principal component analysis completely discriminated L. major-infected MΦ from L. amazonensis-infected cells regarding infection intensity and autophagic features of parasite-induced PV. CONCLUSION: In conclusion, infection by L. amazonensis or L. major, although similarly activates the autophagic flux in infected MΦ and the parasites have their viability favored by autophagy induction, these Leishmania species cause differentiated expression of Atg and distinct interaction of their parasitophorous vacuoles with autophagic vacuoles. These differences are capable to discriminate MΦ infected by L. amazonensis from those infected by L. major


Subject(s)
Humans , Autophagy/immunology , Leishmania/growth & development , Leishmania/genetics , Leishmania/parasitology
20.
Biomédica (Bogotá) ; 37(supl.2): 83-97, jul.-set. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-888528

ABSTRACT

Resumen Introducción. La provincia de Pichincha, Ecuador, es un área endémica de leishmaniasis cutánea, en donde se han determinado como vectores los flebotomíneos antropofílicos con infección natural por Leishmania spp. Sin embargo, no se ha evaluado el papel en la transmisión de las especies zoofílicas. Objetivo. Evaluar la infección natural por Leishmania en dos especies de flebotomíneos zoofílicos, Lutzomyia reburra y Lu. barrettoi majuscula, y en una antropofílica, Lu. trapidoi, así como la endofagia y la sinantropía de estas especies en el noroccidente de Pichincha. Materiales y métodos. Los flebotomíneos se recolectaron en trampas de luz CDC colocadas en diferentes hábitats y altitudes en sitios que son focos de leishmaniasis cutánea. La infección con Leishmania spp. se detectó en el ADN genómico de hembras de las especies de flebotomíneos de interés. Se amplificó el gen espaciador interno de la transcripción del ARN ribosómico, unidad I (ITS1), y los genes de las topoisomerasas mitocondrial II (mtTOPOII) y nuclear II (TopoII). Se determinaron los porcentajes de positividad para Leishmania a escala espaciotemporal, la proporción de endofagia y el índice de sinantropía. Resultados. Se determinó la presencia de infección natural por Le. amazonensis en Lu. reburra (9,5 %) y Lu. b. majuscula (23,8 %); en Lu. trapidoi se detectaron Le. amazonensis, Le. brazilienis y Le. naiffilainsoni. Los flebotomíneos eran asinantrópicos y con baja endofagia. Conclusión. Se registró por primera vez la presencia de infección natural en Lu. reburra y Lu. barrettoi majuscula por Le. amazonensis, y se demostró la importancia de los flebotomíneos zoofílicos en el mantenimiento del ciclo de transmisión de Leishmania spp. en focos endémicos.


Abstract Introduction: The province of Pichincha in Ecuador is an endemic area of cutaneous leishmaniasis, where anthropophilic sand flies with natural infection by Leishmania, have been reported as vectors. However, the role in transmission of zoophilic species has not been evaluated. Objective: To evaluate natural infection by Leishmania in two zoophilic phlebotomine sand fly species, Lutzomyia reburra and Lu. barrettoi majuscula, and one anthropophilic species, Lu. trapidoi, as well as the endophagy and synanthropism of these species in the northwest of Pichincha. Materials and methods: Phlebotomines were collected using CDC light traps in different habitats and altitudes with presence of cutaneous leishmaniasis. Leishmania infection was detected using genomic DNA from females of the collected sand flies. We amplified the internal transcribed spacer gene of ribosomal RNA I (ITS1), the mitochondrial topoisomerase II gene (mtTOPOII), and the nuclear topoisomerase II gene (TopoII). Percentages of positivity for Leishmania, at spatio-temporal scale, proportion of endophagy and synanthropism index were calculated. Results: Natural infection was determined for Le. amazonensis in Lu. reburra (9.5%) and Lu. b. majuscula (23.8%), while in Lu. trapidoi we detected Le. amazonensis, Le. brazilienis and Le. naiffilainsoni. Phlebotomines were asynanthropic and with low endophagy. Conclusion: Natural infection with Le. amazonensis was recorded for the first time in Lu. reburra and Lu. b. majuscula, demonstrating the importance of zoophilic phlebotomines in the maintenance of the Leishmania transmission cycle in endemic foci.


Subject(s)
Animals , Female , Psychodidae/parasitology , Leishmaniasis, Cutaneous/transmission , Insect Vectors/parasitology , Leishmania/isolation & purification , Phylogeny , Species Specificity , Protozoan Proteins/genetics , Cell Nucleus/enzymology , DNA, Protozoan/analysis , Leishmaniasis, Cutaneous/parasitology , DNA Topoisomerases, Type II/genetics , DNA, Ribosomal Spacer/analysis , Ecuador , Feeding Behavior , Phylogeography , Leishmania/physiology , Leishmania/genetics , Mitochondria/enzymology
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