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1.
Mem Inst Oswaldo Cruz ; 119: e230173, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324879

RESUMO

BACKGROUND: The incidence of visceral leishmaniasis (VL) has increased in the Southern region of Brazil in recent years, especially in the State of Paraná. New species have been suggested with potential to act as vector in VL endemic areas. OBJECTIVES: Identify the Leishmania species in sand fly specimens collected from 2016 to 2018 in the municipality of Itaperuçu, Vale do Ribeira, Paraná, Brazil. METHODS: Light traps were used for collections and for the analysis of sand fly were used the multiplex polymerase chain reaction (PCR) methodology and subsequent sequencing. FINDINGS: Among the collected specimens, 88.62% were attributed to the species Nyssomyia neivai, which were grouped into 176 pools. Three positive pools were detected: two with Leishmania (Viannia) braziliensis and one with L. (Leishmania) infantum. The positivity rate for the parasite was 0.25% based on the presence of at least one infected insect in the pool. MAIN CONCLUSIONS: The detection of L. infantum in Ny. neivai draws attention due to its abundance and anthropophily in the State of Paraná. Moreover, this finding is considered as an alert and suggests that the vector competence of Ny. neivai and the criteria for its incrimination should be carried out, given its wide distribution in southern of Brazil.


Assuntos
Leishmania braziliensis , Leishmania infantum , Leishmaniose Visceral , Phlebotomus , Psychodidae , Animais , Leishmania infantum/genética , Brasil/epidemiologia , Psychodidae/parasitologia , Leishmania braziliensis/genética , DNA
2.
Mem Inst Oswaldo Cruz ; 119: e230181, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324880

RESUMO

BACKGROUND: In Brazil, transmission of visceral and cutaneous leishmaniasis has expanded geographically over the last decades, with both clinical forms occurring simultaneously in the same area. OBJECTIVES: This study characterised the clinical, spatial, and temporal distribution, and performed entomological surveillance and natural infection analysis of a leishmaniasis-endemic area. METHODS: In order to characterise the risk of leishmaniasis transmission in Altos, Piauí, we described the clinical and socio-demographic variables and the spatial and temporal distribution of cases of American visceral leishmaniasis (AVL) and American cutaneous leishmaniasis (ACL) cases and identified potential phlebotomine vectors. FINDINGS: The urban area concentrated almost 54% of ACL and 86.8% of AVL cases. The temporal and spatial distribution of AVL and ACL cases in Altos show a reduction in the number of risk areas, but the presence of permanent disease transmission foci is observed especially in the urban area. 3,808 phlebotomine specimens were captured, with Lutzomyia longipalpis as the most frequent species (98.45%). Of the 35 females assessed for natural infection, one specimen of Lu. longipalpis tested positive for the presence of Leishmania infantum and Leishmania braziliensis DNA. MAIN CONCLUSION: Our results indicate the presence of risk areas for ACL and AVL in the municipality of Altos and highlight the importance of entomological surveillance to further understand a possible role of Lu. longipalpis in ACL transmission.


Assuntos
Leishmania infantum , Leishmaniose Cutânea , Leishmaniose Visceral , Animais , Feminino , Brasil/epidemiologia , Insetos Vetores/genética , Leishmaniose Cutânea/epidemiologia , Leishmaniose Visceral/epidemiologia , Leishmania infantum/genética , DNA
3.
Mem Inst Oswaldo Cruz ; 115: e200157, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206821

RESUMO

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.


Assuntos
DNA/análise , Insetos Vetores/genética , Leishmania/genética , Psychodidae/parasitologia , Animais , Brasil , DNA de Protozoário/análise , Feminino , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Leishmaniose Cutânea/transmissão , Reação em Cadeia da Polimerase , Psychodidae/classificação
4.
Mem Inst Oswaldo Cruz ; 115: e200113, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111757

RESUMO

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.


Assuntos
Leishmania braziliensis , Leishmania , Proteômica , Psychodidae , Animais , Linhagem Celular , Leishmania/genética , Leishmania braziliensis/genética , Psychodidae/parasitologia , Transcriptoma
5.
Mem Inst Oswaldo Cruz ; 112(1): 75-78, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28076470

RESUMO

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.


Assuntos
Insetos Vetores/parasitologia , Leishmania/classificação , Leishmaniose Cutânea/transmissão , Psychodidae/parasitologia , Animais , Brasil , DNA de Protozoário/genética , Insetos Vetores/classificação , Leishmania/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex , Psychodidae/classificação
6.
Mem Inst Oswaldo Cruz ; 108(5): 578-85, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23903972

RESUMO

Phlebotomine sandflies were captured in rural settlement and periurban areas of the municipality of Guaraí in the state of Tocantins (TO), an endemic area of American cutaneous leishmaniasis (ACL). Forty-three phlebotomine species were identified, nine of which have already been recognised as ACL vectors. Eleven species were recorded for the first time in TO. Nyssomyia whitmani was the most abundant species, followed by Evandromyia bourrouli, Nyssomyia antunesi and Psychodopygus complexus. The Shannon-Wiener diversity index and the evenness index were higher in the rural settlement area than in the periurban area. The evaluation of different ecotopes within the rural area showed the highest frequencies of Ev. bourrouli and Ny. antunesi in chicken coops, whereas Ny. whitmani predominated in this ecotope in the periurban area. In the rural settlement area, Ev. bourrouli was the most frequently captured species in automatic light traps and Ps. complexus was the most prevalent in Shannon trap captures. The rural settlement environment exhibited greater phlebotomine biodiversity than the periurban area. Ps. complexus and Psychodopygus ayrozai naturally infected with Leishmania (Viannia) braziliensis were identified. The data identified Ny. whitmani as a potential ACL vector in the periurban area, whereas Ps. complexus was more prevalent in the rural environment associated with settlements.


Assuntos
Insetos Vetores/classificação , Psychodidae/classificação , Animais , Brasil , Leishmaniose Cutânea/transmissão , Densidade Demográfica , População Rural , Estações do Ano , População Urbana
7.
PLoS One ; 18(2): e0281289, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36730314

RESUMO

The subfamily Phlebotominae comprises important insects for public health. The use of complementary tools such as molecular taxonomy is necessary for interspecific delimitation and/or discovery of cryptic species. Here, we evaluated the DNA barcoding tool to identify different species in the southwestern Brazilian Amazon. For this, we collected sand flies in forest fragments along the highway BR-317, in the municipality of Brasiléia, state of Acre, Brazil. The specimens were DNA-barcoded using a fragment of the cytochrome c oxidase subunit I (COI) gene. The sequences were analyzed to generate K2P pairwise genetic distances and a Neighbour-joining tree. The sand fly barcodes were also clustered into Molecular Operation Taxonomic Units (MOTU) using Automatic Barcode Gap Discovery (ABGD) approach. A total of 59 COI sequences comprising 22 nominal species and ten genera were generated. Of these, 11 species had not been sequenced before, thus being new COI sequences to science. Intraspecific genetic distances ranged between 0 and 4.9%, with Pintomyia serrana presenting the highest values of genetic distance, in addition to having been partitioned into three MOTUs. Regarding the distances to the nearest neighbour, all species present higher values in relation to the maximum intraspecific distance, in addition to forming well supported clusters in the neighbour-joining analysis. The DNA barcoding approach is useful for the molecular identification of sand flies from Brasiléia, state of Acre, and was efficient in detecting cryptic diversity of five species which can be confirmed in future studies using an integrative approach. We also generated new COI barcodes for Trichophoromyia auraensis, Nyssomyia shawi, and Psychodopygus paraensis, which may play a role in the transmission of Leishmania spp. in the Brazilian Amazon.


Assuntos
Phlebotomus , Psychodidae , Animais , Psychodidae/genética , Código de Barras de DNA Taxonômico , Brasil , Phlebotomus/genética , DNA
8.
PLoS Negl Trop Dis ; 17(6): e0011388, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37276231

RESUMO

BACKGROUND: Leishmaniases are vector borne diseases caused by Leishmania spp. parasites transmitted by female sandflies (Diptera: Psychodidae) whose geographic distribution is influenced by environmental factors. Among the main tools for studying the distribution of vector species, modeling techniques are used to analyze the influence of climatic and environmental factors on the distribution of these insects and their association with human cases of the disease. METHODOLOGY/PRINCIPAL FINDINGS: Here, we used a multiscale ecological niche modeling approach to assess the environmental suitability of sandfly vectors of the etiological agents of Visceral (VL) and American Cutaneous Leishmaniasis (ACL) in Piauí state, northeastern Brazil, and then evaluated their relationship with human disease incidence. For this, we obtained the geographic coordinates of the vector species Lutzomyia longipalpis and Nyssomyia whitmani through literature review, online databases and unpublished records. These data were used for the development of predictive models of the distribution of both sandflies species based on climatic and environmental variables. Finally, the environmental suitability for the presence of these vectors was compared with the incidence of both the diseases at the municipality level. The final models for each sandfly species showed good predictive powers with performance metric values of 0.889 for Lu. longipalpis and 0.776 for Ny. whitmani. The areas with greater environmental suitability for the presence of these species were concentrated in the central-north region of Piauí and coincide with the location of those municipalities presenting higher incidences of VL and ACL, situated in the central-north and extreme north of the state, respectively. The south and southeast regions of Piauí state have low incidence of these diseases and presented low environmental suitability for the presence of both vectors. CONCLUSIONS/SIGNIFICANCE: We discuss how predictive modeling can guide entomological and epidemiological surveillances and recommend an increased supervision and control activities in Teresina (capital of the state of Piaui), Altos and Pedro II, in addition to other municipalities with similar social and environmental characteristics.


Assuntos
Leishmaniose Cutânea , Phlebotomus , Psychodidae , Animais , Feminino , Humanos , Incidência , Brasil/epidemiologia , Insetos Vetores/parasitologia , Leishmaniose Cutânea/parasitologia , Psychodidae/parasitologia
9.
Exp Parasitol ; 126(4): 570-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20553928

RESUMO

Cysteine proteinases are an important virulence factor in Leishmania parasites. In this study we analyzed the cysteine proteinase expression of infective Leishmania (Viannia) braziliensis promastigotes, examining the expression induced by successive in vitro passages in culture. We observed that this parasite presents a decrease in its virulence over BALB/c macrophages, after successive passages in culture, but still they present proteinase activity, being capable of hydrolyzing the substrate pGlu-Phe-Leu-p Nitroanilide at pH 7.0. This proteinase activity also decreases in the course of the successive passages. Additionally, the decrease in the amount of CPB proteins following successive passages of promastigotes was verified by immunoblotting assays, using an anti-CPB antiserum. Real-time PCR assays were performed to assess the relative cpb expression when compared to a housekeeping gene in promastigote cDNA preparations from the first, fourth and seventh passages. Interestingly, the data indicate a relative increase in cpb gene transcripts as the promastigotes were maintained under in vitro culture: 2.2 times higher for fourth and 2.7 times higher for seventh passages when compared to the first passage. Thus, the information gathered here shows that the expression of cysteine proteinases is modified during in vitro cultivation of L. (V.) braziliensis promastigotes.


Assuntos
Cisteína Proteases/biossíntese , Regulação Enzimológica da Expressão Gênica/fisiologia , Leishmania braziliensis/enzimologia , Fatores de Virulência/biossíntese , Animais , Cisteína Proteases/genética , Immunoblotting , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania braziliensis/patogenicidade , Macrófagos Peritoneais/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inoculações Seriadas , Virulência , Fatores de Virulência/genética
10.
PLoS One ; 14(7): e0219626, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31306447

RESUMO

In the border region between Brazil and French Guiana, American cutaneous leishmaniasis is a worrisome public health issue, and entomological studies are required there to better identify classical and putative emerging transmission patterns. The present study aimed to detect and characterize Leishmania DNA in the phlebotomine population of Oiapoque (Amapá State, Brazil). Phlebotomines were captured in anthropized and wild environments in the outskirts of Oiapoque municipality, using CDC light traps installed in vertical (ground/canopy level) and horizontal (peridomicile/extradomicile/forest-edge/forest) strata. Captured specimens were identified according to their morphology. Females were processed for Leishmania DNA detection and characterization using a multiplex polymerase chain reaction targeting kinetoplast DNA (kDNA) and the phlebotomine cacophony gene. The kDNA positive samples were characterized by cloning and sequencing the Leishmania 234 bp-hsp70 gene. Among the 3957 phlebotomine specimens captured, 26 pooled female samples were positive for Leishmania (Viannia) spp. DNA. Sequencing analysis allowed species-specific identification of L. (V.) braziliensis DNA in Trichophoromyia ininii, Bichromomyia flaviscutellata, Nyssomyia umbratilis, and Evandromyia infraspinosa, and L. (V.) guyanensis DNA in Ny. umbratilis. A pooled sample of Ny. umbratilis was positive for both L. (V.) braziliensis and L. (V.) guyanensis DNA. The present study provided additional information regarding ACL ecology in Oiapoque, highlighting the presence of L. (V.) braziliensis DNA in different phlebotomine species. The epidemiological implications of these findings and the determinant incrimination of L. (V.) braziliensis as proven vectors in that region must be clarified. In this regard, studies on Leishmania spp. infection and suggestive anthropophilic behavior of associated phlebotomines need to be prioritized in entomological surveillance.


Assuntos
DNA de Cinetoplasto/análise , Leishmania/genética , Psychodidae/parasitologia , Animais , Brasil , Ecologia , Feminino , Florestas , Guiana Francesa , Geografia , Insetos Vetores , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
11.
Mem. Inst. Oswaldo Cruz ; 119: e230173, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1534935

RESUMO

BACKGROUND The incidence of visceral leishmaniasis (VL) has increased in the Southern region of Brazil in recent years, especially in the State of Paraná. New species have been suggested with potential to act as vector in VL endemic areas. OBJECTIVES Identify the Leishmania species in sand fly specimens collected from 2016 to 2018 in the municipality of Itaperuçu, Vale do Ribeira, Paraná, Brazil. METHODS Light traps were used for collections and for the analysis of sand fly were used the multiplex polymerase chain reaction (PCR) methodology and subsequent sequencing. FINDINGS Among the collected specimens, 88.62% were attributed to the species Nyssomyia neivai, which were grouped into 176 pools. Three positive pools were detected: two with Leishmania (Viannia) braziliensis and one with L. (Leishmania) infantum. The positivity rate for the parasite was 0.25% based on the presence of at least one infected insect in the pool. MAIN CONCLUSIONS The detection of L. infantum in Ny. neivai draws attention due to its abundance and anthropophily in the State of Paraná. Moreover, this finding is considered as an alert and suggests that the vector competence of Ny. neivai and the criteria for its incrimination should be carried out, given its wide distribution in southern of Brazil.

12.
Mem. Inst. Oswaldo Cruz ; 119: e230181, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1534931

RESUMO

BACKGROUND In Brazil, transmission of visceral and cutaneous leishmaniasis has expanded geographically over the last decades, with both clinical forms occurring simultaneously in the same area. OBJECTIVES This study characterised the clinical, spatial, and temporal distribution, and performed entomological surveillance and natural infection analysis of a leishmaniasis-endemic area. METHODS In order to characterise the risk of leishmaniasis transmission in Altos, Piauí, we described the clinical and socio-demographic variables and the spatial and temporal distribution of cases of American visceral leishmaniasis (AVL) and American cutaneous leishmaniasis (ACL) cases and identified potential phlebotomine vectors. FINDINGS The urban area concentrated almost 54% of ACL and 86.8% of AVL cases. The temporal and spatial distribution of AVL and ACL cases in Altos show a reduction in the number of risk areas, but the presence of permanent disease transmission foci is observed especially in the urban area. 3,808 phlebotomine specimens were captured, with Lutzomyia longipalpis as the most frequent species (98.45%). Of the 35 females assessed for natural infection, one specimen of Lu. longipalpis tested positive for the presence of Leishmania infantum and Leishmania braziliensis DNA. MAIN CONCLUSION Our results indicate the presence of risk areas for ACL and AVL in the municipality of Altos and highlight the importance of entomological surveillance to further understand a possible role of Lu. longipalpis in ACL transmission.

13.
Acta Trop ; 107(1): 66-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18502392

RESUMO

In order to identify Lutzomyia spp. naturally infected by Leishmania parasites a PCR multiplex assay coupled to non-isotopic hybridization was used for the analysis of insect samples collected by CDC light traps in an endemic area of visceral leishmaniasis (VL) in the municipality of Corumbá, Mato Grosso do Sul State, Brazil in May/June 2006. Wild sand flies were identified and grouped into pools of 10 female specimens and 27 groups in total were collected. Positive results were obtained from Lutzomyia cruzi (2 out of 13 pools) and Lutzomyia forattinii (1 out of 14 pools). The positive pools were confirmed as being infected by Leishmania infantum chagasi after hybridizing the PCR products with a species-specific biotinylated probe derived from the kinetoplast minicircle conserved sequence. Given that we detected infection in 3 out of 27 groups and that there was at least 1 infected insect in each, it was possible to infer an infection rate of 1.5% for Lu. cruzi and 0.7% for Lu. forattinii in the analyzed samples. These results confirm the vectorial role of Lu. cruzi in transmitting L. infantum chagasi and suggest Lu. forattinii as a potential VL vector in the municipality of Corumbá, where notifications of the disease in humans and dogs have increased over the last two decades.


Assuntos
Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/parasitologia , Reação em Cadeia da Polimerase/métodos , Psychodidae/parasitologia , Animais , Brasil/epidemiologia , DNA de Cinetoplasto/genética , Vetores de Doenças , Doenças Endêmicas , Feminino , Humanos , Leishmania infantum/genética , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/transmissão , Masculino , Hibridização de Ácido Nucleico/métodos
14.
Acta Trop ; 105(1): 92-4, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17953938

RESUMO

This paper is the first to report visceral leishmaniasis in domestic cats (Felis catus domesticus) from an endemic area in Rio de Janeiro state, Brazil. A relatively high seroprevalence of 25% was observed although none of them have presented any symptom. Our results support the observation of previous authors, suggesting that cats may be considered as alternative domestic hosts of visceral leishmaniasis and should be included in serological investigations performed in endemic areas.


Assuntos
Doenças do Gato/diagnóstico , Leishmaniose Visceral/diagnóstico , Animais , Brasil/epidemiologia , Doenças do Gato/epidemiologia , Gatos , Leishmaniose Visceral/epidemiologia , Estudos Soroepidemiológicos
15.
Rev Soc Bras Med Trop ; 51(3): 376-381, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29972573

RESUMO

INTRODUCTION: This study proposes to identify the Leishmania species found in the skin lesions of cutaneous leishmaniasis (CL) patients from Brasiléia municipality (Acre). METHODS: Skin biopsy imprints or biopsy fragments were assayed via kDNA-PCR/RFLP and FRET-real-time PCR. RESULTS: Of individuals with suspected CL, 18 were positive for Leishmania kDNA. Leishmania (Viannia) braziliensis (61.1%) and Leishmania (Viannia) guyanensis (5.5%) were identified in the positive samples. CONCLUSIONS: These results are congruent with the previous reports in Acre and Bolivia, revealing L. braziliensis as the most prevalent species. L. guyanensis identification also corroborates with the epidemiology of the disease in the Amazon Basin.


Assuntos
Leishmania braziliensis/genética , Leishmania guyanensis/genética , Leishmaniose Cutânea/diagnóstico , Adolescente , Adulto , Biópsia , Brasil/epidemiologia , Criança , Pré-Escolar , DNA de Cinetoplasto/genética , DNA de Protozoário/genética , Doenças Endêmicas , Feminino , Humanos , Lactente , Recém-Nascido , Leishmaniose Cutânea/epidemiologia , Masculino , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
16.
Parasit Vectors ; 11(1): 614, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30501613

RESUMO

BACKGROUND: The sand fly Lutzomyia longipalpis is the main vector of American visceral leishmaniasis, a disease caused by parasites of the genus Leishmania. Adults of this insect feed on blood (females only) or sugar from plant sources, but their digestion of carbohydrates is poorly studied. Beta-glycosides as esculin and amygdalin are plant compounds and release toxic compounds as esculetin and mandelonitrile when hydrolyzed. Beta-glucosidase and trehalase are essential enzymes in sand fly metabolism and participate in sugar digestion. It is therefore possible that the toxic portions of these glycosides, released during digestion, affect sand fly physiology and the development of Leishmania. RESULTS: We tested the oral administration to sand flies of amygdalin, esculin, mandelonitrile, and esculetin in the sugar meal. These compounds significantly decreased the longevity of Lutzomyia longipalpis females and males. Lutzomyia longipalpis adults have significant hydrolytic activities against esculin and feeding on this compound cause changes in trehalase and ß-glucosidase activities. Female trehalase activity is inhibited in vitro by esculin. Esculin is naturally fluorescent, so its ingestion may be detected and quantified in whole insects or tissue samples stored in methanol. Mandelonitrile neither affected the amount of sugar ingested by sand flies nor showed repellent activity. Our results show that mandelonitrile significantly reduces the viability of L. amazonensis, L. braziliensis, L. infantum and L. mexicana, in a concentration-dependent manner. Esculetin caused a similar effect, reducing the number of L. infantum and L. mexicana. Female L. longipalpis fed on mandelonitrile had a reduction in the number of parasites and prevalence of infection after seven days of infection with L. mexicana, either by counting in a Neubauer chamber or by qPCR assays. CONCLUSIONS: Glycosides have significant effects on L. longipalpis longevity and metabolism and also affect the development of parasites in culture and inside the insect. These observations might help to conceptualize new vector control strategies using transmission blocking sugar baits.


Assuntos
Glicosídeos/toxicidade , Controle de Insetos/métodos , Insetos Vetores/enzimologia , Insetos Vetores/parasitologia , Leishmania/crescimento & desenvolvimento , Psychodidae/enzimologia , Psychodidae/parasitologia , Acetonitrilas/toxicidade , Amigdalina/toxicidade , Animais , Esculina/toxicidade , Feminino , Glicosídeos/administração & dosagem , Leishmaniose/prevenção & controle , Leishmaniose/transmissão , Masculino , Trealase/efeitos dos fármacos , Umbeliferonas/administração & dosagem , Umbeliferonas/toxicidade , beta-Glucosidase/efeitos dos fármacos
17.
Trans R Soc Trop Med Hyg ; 99(12): 905-13, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16143358

RESUMO

To identify naturally infected Lutzomyia spp. by Leishmania (Viannia) braziliensis, a PCR multiplex non-isotopic hybridisation assay was developed for the analysis of insect samples collected in distinct areas of the municipality of Rio de Janeiro (Brazil), from March to December 2003. Data from experimental infection indicate that the method can detect one individual infected insect out of ten. Wild sand flies were classified and grouped into pools of 10 specimens each, reaching a total of 40 female groups. Positive results were obtained with pools of Lu. intermedia (5/32) and Lu. migonei (3/5) collected in two areas from the district of Jacarepaguá presenting recent cases of human and canine leishmaniasis. Considering eight infected groups (8/40) with at least one positive insect in each, it was possible to infer an infection rate of 2%. This technique permits the synchronous processing of a large number of samples, in order to investigate infection rates in sand fly populations and to identify potential insect vectors. The results presented here represent the first molecular approach used to infer the natural infection index in both Lutzomyia spp. and constitute essential data to the understanding of leishmaniasis ecoepidemiology in endemic areas from Rio de Janeiro.


Assuntos
Insetos Vetores/parasitologia , Leishmania braziliensis/isolamento & purificação , Psychodidae/parasitologia , Animais , Brasil/epidemiologia , DNA de Protozoário/análise , Doenças Endêmicas , Feminino , Humanos , Immunoblotting/métodos , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/transmissão , Reação em Cadeia da Polimerase/métodos
18.
Mem. Inst. Oswaldo Cruz ; 115: e200113, 2020. tab, graf
Artigo em Inglês | LILACS, SES-SP | ID: biblio-1135235

RESUMO

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.


Assuntos
Animais , Psychodidae/parasitologia , Leishmania braziliensis/genética , Proteômica , Leishmania/genética , Linhagem Celular , Transcriptoma
19.
Parasit Vectors ; 7: 360, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25103985

RESUMO

BACKGROUND: Notifications concerning American Cutaneous Leishmaniasis have increased in recent years in the state of Acre, Brazil. Despite identification of distinct Leishmania species isolated from cutaneous lesions, there are still no records of visceral leishmaniasis in the state. However, studies on the sand fly fauna in this region are still limited. FINDINGS: Insects were collected from April 2011 to April 2012, using HP light traps distributed in four residential areas and one recreational area in Rio Branco, Capital of the State of Acre in the Amazon region of Brazil. A total of 456 sand flies were collected, comprising 256 females and 200 males. Taxonomic identification revealed 16 Phlebotominae genera and 23 species, as follows: Trichophoromyia auraensis, Nyssomyia whitmani, Nyssomyia antunesi, Pressatia choti, Evandromyia saulensis, Evandromyia walkeri, Evandromyia begonae, Migonemyia migonei, Pintomyia serrana, Psychodopygus paraensis, Sciopemyia sordelii, Migonemyia pusilla, Pintomyia nevesi, Brumptomyia avellari, Micropygomyia acanthopharynx, Micropygomyia micropyga, Pintomyia odax, Lutzomyia sherlocki, Pressatia calcarata, Pressatia duncanae, Bichromomyia flaviscutellata, Evandromyia bourrouli and Evandromyia bacula. From this group, Tr. auraensis and Ny. whitmani were the most abundant species in both forested areas and the peridomiciliary environment. CONCLUSIONS: We find that the sand fly fauna in the urban and peri urban areas of Rio Branco is very diverse comprising 23 species, as diverse as that in areas of primary forest. Some species, such as Nyssomyia whitmani, Ny. antunesi and Bichromomyia flaviscutellata are known vectors of parasites responsible for cutaneous leishmaniasis, and Trichophoromyia auraensis is a putative vector in this Amazonian region.


Assuntos
Leishmaniose Visceral/epidemiologia , Psychodidae/classificação , Psychodidae/fisiologia , Animais , Brasil/epidemiologia , Cidades , Feminino , Humanos , Masculino
20.
Rev. Soc. Bras. Med. Trop ; 51(3): 376-381, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1041460

RESUMO

Abstract INTRODUCTION This study proposes to identify the Leishmania species found in the skin lesions of cutaneous leishmaniasis (CL) patients from Brasiléia municipality (Acre). METHODS Skin biopsy imprints or biopsy fragments were assayed via kDNA-PCR/RFLP and FRET-real-time PCR. RESULTS Of individuals with suspected CL, 18 were positive for Leishmania kDNA. Leishmania (Viannia) braziliensis (61.1%) and Leishmania (Viannia) guyanensis (5.5%) were identified in the positive samples. CONCLUSIONS These results are congruent with the previous reports in Acre and Bolivia, revealing L. braziliensis as the most prevalent species. L. guyanensis identification also corroborates with the epidemiology of the disease in the Amazon Basin.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Adulto Jovem , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Leishmania guyanensis/genética , Biópsia , Polimorfismo de Fragmento de Restrição , Brasil/epidemiologia , DNA de Protozoário/genética , Leishmaniose Cutânea/epidemiologia , DNA de Cinetoplasto/genética , Doenças Endêmicas , Reação em Cadeia da Polimerase em Tempo Real
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