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1.
Artigo em Inglês | MEDLINE | ID: mdl-33503150

RESUMO

American Tegumentary Leishmaniasis (ATL) is endemic in the municipality of Montes Claros, Minas Gerais State. The use of geotechnology such as spatial statistics and remote sensing has contributed to a better understanding of the eco-epidemiology of diseases, and consequently a better definition of control strategies. This study aimed to analyze the spatial distribution of probable sites of cases of ATL infection (2007-2011) in the municipality of Montes Claros and to identify related socio-environmental factors. Data on ATL cases notification were obtained from the Municipal Health Department of Montes Claros. The annual incidence of ATL in the municipality was calculated and the probable sites of infection were georeferenced. Crude Rate and the Local Empirical Bayesian Rate were calculated with census sectors considered as the unit of analysis. The Normalized Difference Vegetation Index (NDVI) was calculated from LANDSAT 5 TM images. The spatial association between the crude rate of ATL and the NDVI of the census tracts was evaluated using the Local Bivariate of Moran I. The socio-environmental aspects of household structures were assessed based on a structured questionnaire. The incidence of ATL in the evaluated period ranged from 6.2 to 16.6 cases/100,000 inhabitants. The highest rates of ATL occurrence were found in the census sectors located in the rural area and in the peripheral census sectors in the city. Through the Empirical Bayes Smoothed Rate map, it was found that in the peripheral areas of the city, the rates of ATL occurrence were lower than in the rural area and their values decreased as they approach the city center. Local Bivariate of Moran I showed a positive correlation between NDVI and crude ATL rates, with significant high-high clusters observed in the rural area and in the census sectors in the Western peripheral area of the city that have experienced an urban expansion concomitant to the period investigated. In most homes of people affected by the disease, there were domestic animals and organic matter in the peridomicile. In addition, a high percentage of individuals affected by ATL reported the presence of rodents circulating near their homes. In conclusion, it is possible that the disorderly expansion process in the city of Montes Claros favored the establishment of the ATL periurban and urban transmission cycle. These regions deserve special attention from health surveillance to combat this zoonosis.


Assuntos
Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Animais , Teorema de Bayes , Brasil/epidemiologia , Cidades/epidemiologia , Saúde Ambiental , Incidência , Leishmania/genética , Fatores Socioeconômicos , Análise Espacial
2.
Rev Soc Bras Med Trop ; 53: e20200255, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33331607

RESUMO

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.


Assuntos
Leishmania braziliensis , Leishmania , Leishmaniose Cutânea , Brasil/epidemiologia , Humanos , Leishmania/genética , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/epidemiologia , Polimorfismo de Fragmento de Restrição , Estados Unidos
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.
Rev Soc Bras Med Trop ; 53: e20200006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111906

RESUMO

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.


Assuntos
Leishmania , Leishmaniose Cutânea , Adolescente , Adulto , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Povos Indígenas , Lactente , Recém-Nascido , Leishmania/genética , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/epidemiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Adulto Jovem
6.
Mikrobiyol Bul ; 54(3): 429-443, 2020 Jul.
Artigo em Turco | MEDLINE | ID: mdl-32755519

RESUMO

Although asexual reproduction has been attributed to Leishmania species, genetic exchange has recently been demonstrated, which helped emerging of hybrid isolates. Situated on the crossroads between three continents, Leishmania hybrids may be present in Turkey. In Turkey, visceral leishmaniasis caused by Leishmania infantum is less common, while cutaneous leishmaniasis (CL) caused by Leishmania tropica and L.infantum could reach 2500 reported cases a year. Our aim was to investigate genetic variability of local Leishmania species and presence of hybrid Leishmania strains in Turkey. Twenty CL patients from Sanliurfa and Hatay, where only L.tropica and both L.tropica and L.infantum cause CL, respectively, were registered equally. All isolates were assessed with real-time polymerase chain reaction (Rt-PCR), isoenzyme analysis, gene sequencing, two-dimensional gel electrophoresis (2D-PAGE) and MALDI-TOF/TOFMS followed by in vivo analyses on mouse model. Identification of differentially expressed proteins was performed. These proteins were confirmed by sequence analysis. All isolates from Sanliurfa were found to be L.tropica which caused cutaneous infection in mice. However, one of 10 isolates from Hatay was found as Leishmania major which caused cutaneous infection. Five isolates were found as L.tropica with Rt-PCR and gene sequencing, one of which had one different protein from the reference L.tropica strain and caused cutaneous infection. Four of the five isolates had five different proteins compared to reference strain and caused both cutaneous and visceral infections. Remaining four isolates showed double melting curves in Rt-PCR, which were concordant with L.tropica and L.infantum. Their sequencing and isoenzyme analyses indicated them as L.infantum. They had six different proteins compared to reference L.infantum strain and caused cutaneous and visceral infections. It is concluded that the isolates with different proteins were hybrid Leishmania species. In the present study, outcomes of the proteomics, genomics, clinical manifestations and tissue tropism on animal models were evaluated together for the first time. In addition to L.tropica and L.infantum, L.major was identified as a causative agent for CL and hybrids of L.infantum/tropica were also shown to be present.


Assuntos
Variação Genética , Leishmania , Leishmaniose Cutânea , Leishmaniose Visceral , Animais , Modelos Animais de Doenças , Humanos , Leishmania/genética , Leishmaniose Cutânea/parasitologia , Leishmaniose Visceral/parasitologia , Camundongos , Turquia
7.
PLoS Negl Trop Dis ; 14(8): e0008507, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32841279

RESUMO

BACKGROUND: Cutaneous leishmaniasis is one of the most neglected tropical diseases increasing in its public health importance. In Ethiopia over 28 million people are living at risk of infection. METHOD: Institution based cross-sectional study was conducted at Borumeda Hospital from February to May 2019. A total 205 leishmaniasis suspected patients were included by systematic random sampling technique. Socio demographic characteristics were collected using pre-tested questionnaires. Parasitological investigation was done from skin slit sample by using Geimsa staining method. Species identification was done by PCR-RFLP. Data were entered in to EpiData version 3.1 and analyzed using SPSS version 20 software. P-value of ≤ 0.05 was considered as statistically significant. RESULT: A total of 205 participants consisting 59% male and 41% female included in this study. The mean age (±SD) of the study participants was 31.9 (±14.29). The overall prevalence of cutaneous leishmaniasis was 22.4% (46/205). The prevalence in males (13.7%) was higher than in females (8.8%). It was more prevalent in the age group 16-45years old (15.6%). Clinically, 60% of patients' hade single lesion with 1.55 average number of lesions. About 30.7% of patients' had indurated plaque type of lesion. Most of the lesions were found on head and face (59%). House near to farmland, presence of hyrax in the village and presence of other cutaneous leishmaniasis cases in the neighborhood were independent predicator of cutaneous leishmaniasis prevalence. L.aethopica was found to be the etiologic agent of cutaneous leishmaniasis in the study participants. CONCLUSION: The prevalence of cutaneous leishmaniasis was 22.4%, this alerts the need of intervention. It is statistically associated with house near to farm land, presence of other cutaneous leishmaniasis cases in the neighborhood and presence of hyrax in village. Head and face were the most common sites of lesion.


Assuntos
Leishmania/genética , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos Transversais , DNA de Protozoário/análise , Etiópia/epidemiologia , Feminino , Humanos , Leishmaniose Cutânea/diagnóstico , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência , Adulto Jovem
8.
PLoS Negl Trop Dis ; 14(8): e0008509, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32804927

RESUMO

Leishmania species are responsible for a broad spectrum of diseases, denominated Leishmaniasis, affecting over 12 million people worldwide. During the last decade, there have been impressive efforts for sequencing the genome of most of the pathogenic Leishmania spp. as well as hundreds of strains, but large-scale proteomics analyses did not follow these achievements and the Leishmania proteome remained mostly uncharacterized. Here, we report a comprehensive comparative study of the proteomes of strains representing L. braziliensis, L. panamensis and L. guyanensis species. Proteins extracted by SDS-mediated lysis were processed following the multi-enzyme digestion-filter aided sample preparation (FASP) procedure and analysed by high accuracy mass spectrometry. "Total Protein Approach" and "Proteomic Ruler" were applied for absolute quantification of proteins. Principal component analysis demonstrated very high reproducibility among biological replicates and a very clear differentiation of the three species. Our dataset comprises near 7000 proteins, representing the most complete Leishmania proteome yet known, and provides a comprehensive quantitative picture of the proteomes of the three species in terms of protein concentration and copy numbers. Analysis of the abundance of proteins from the major energy metabolic processes allow us to highlight remarkably differences among the species and suggest that these parasites depend on distinct energy substrates to obtain ATP. Whereas L. braziliensis relies the more on glycolysis, L. panamensis and L. guyanensis seem to depend mainly on mitochondrial respiration. These results were confirmed by biochemical assays showing opposite profiles for glucose uptake and O2 consumption in these species. In addition, we provide quantitative data about different membrane proteins, transporters, and lipids, all of which contribute for significant species-specific differences and provide rich substrate for explore new molecules for diagnosing purposes. Data are available via ProteomeXchange with identifier PXD017696.


Assuntos
Leishmania/metabolismo , Proteínas de Protozoários/metabolismo , Regulação da Expressão Gênica/fisiologia , Glucose/metabolismo , Leishmania/genética , Consumo de Oxigênio , Proteômica , Proteínas de Protozoários/genética , Especificidade da Espécie
9.
PLoS Negl Trop Dis ; 14(8): e0008380, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797078

RESUMO

In French Guiana, five species are associated with Cutaneous Leishmaniasis (CL). Though infections with Leishmania guyanensis, L. (V.) braziliensis and L. (L.) amazonensis have been extensively described, there are few available clinical and genetic data on L. (V.) lainsoni and L. (V.) naiffi. We determined the clinical and epidemiological features of all cases of CL due to L. (V.) naiffi and L. (V.) lainsoni diagnosed in French Guiana between 2003 and 2019. Phylogenetic analysis was performed by sequencing a portion of HSP70 and cyt b genes. Five cases of L. naiffi and 25 cases of L. lainsoni were reported. Patients infected by L. (V.) lainsoni were usually infected on gold camps, mostly along the Maroni river (60%), while L. naiffi was observed in French patients infected on the coast (100%). A high number of pediatric cases (n = 5; 20%) was observed for L. (V.) lainsoni. A mild clinical course was observed for all cases of L. (V.) naiffi. HSP70 and cyt b partial nucleotide sequence analysis revealed different geographical clusters within L. (V.) naiffi and L. (V.) lainsoni but no association were found between phylogenetic and clinical features. Our data suggest distinct socio-epidemiological features for these two Leishmania species. Patients seem to get infected with L. (V.) naiffi during leisure activities in anthropized coastal areas, while L. (V.) lainsoni shares common features with L. (V.) guyanensis and braziliensis and seems to be acquired during professional activities in primary forest regions. Phylogenetic analysis has provided information on the intraspecific genetic variability of L. (V.) naiffi and L. (V.) lainsoni and how these genotypes are distributed at the geographic level.


Assuntos
Leishmania/classificação , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Citocromos b/genética , Feminino , Guiana Francesa/epidemiologia , Proteínas de Choque Térmico HSP70/genética , Humanos , Lactente , Leishmania/genética , Leishmania/patogenicidade , Leishmaniose Cutânea/patologia , Atividades de Lazer , Masculino , Pessoa de Meia-Idade , Mineração , Doenças Negligenciadas , Filogenia , Estudos Retrospectivos , Análise de Sequência de DNA
10.
Parasitol Res ; 119(9): 3041-3051, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32779021

RESUMO

Our objective was to investigate clinical progression, presence of parasites and DNAs, parasite loads, and histological alterations in BALB/c mice and Syrian golden hamsters after intraperitoneal inoculation with Leishmania (Mundinia) martiniquensis promastigotes with a goal to choosing an appropriate animal model for visceral leishmaniasis. Infections were monitored for 16 weeks. Infected BALB/c mice were asymptomatic during the infection course. Parasite DNAs were detected in the liver at week 8 of infection, followed by clearance in most animals at week 16; whereas in the spleen, parasite DNAs were detected until week 16. These results are correlated to those obtained measuring parasite loads in both organs. No parasite DNA and no alteration in the bone marrow were observed indicating that no dissemination occurred. These results suggest the control of visceralization of L. martiniquensis by BALB/c mice. In hamsters, weight loss, cachexia, and fatigue were observed after week 11. Leishmania martiniquensis parasites were observed in tissue smears of the liver, spleen, and bone marrow by week 16. Parasite loads correlated with those from the presence of parasites and DNAs in the examined tissues. Alterations in the liver with nuclear destruction and cytoplasmic degeneration of infected hepatocytes, presence of inflammatory infiltrates, necrosis of hepatocytes, and changes in splenic architecture and reduction and deformation of white pulp in the spleen were noted. These results indicate a chronic form of visceral leishmaniasis indicating that the hamster is a suitable animal model for the study of pathological features of chronic visceral leishmaniasis caused by L. martiniquensis.


Assuntos
Leishmania/fisiologia , Leishmaniose Visceral/parasitologia , Animais , Cricetinae , Modelos Animais de Doenças , Humanos , Leishmania/genética , Fígado/parasitologia , Masculino , Mesocricetus , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Baço/parasitologia
11.
Am J Trop Med Hyg ; 103(4): 1502-1509, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32700674

RESUMO

There are two main species of Leishmania reported in Thailand, that is, Leishmania siamensis and Leishmania martiniquensis. Moreover, leishmaniasis cases caused by Leishmania donovani complex were also reported. There is still a lack of information concerning risk factors of Leishmania infection in Thailand. This study aimed to identify the risk factors of Leishmania infection caused by these three species among HIV-infected patients. A cross-sectional study was conducted in HIV clinic at Trang Hospital, Thailand. Nested PCR and sequencing were performed to detect Leishmania DNA in blood and saliva samples and identify Leishmania species. A standardized questionnaire was used to interview individuals. A total of 526 patients were recruited in this study. Sixty-three (12.0%) were positive for L. siamensis, 24 (4.6%) were positive for L. martiniquensis, and 23 (4.4%) were positive for L. donovani complex. Risk factors of L. siamensis infection included using intravenous drug (adjusted odds ratio [AOR] 2.01, 95% CI: 1.01-4.02). Risk factors of L. martiniquensis infection included female gender (AOR 4.23, 95% CI: 1.52-11.75), using recreational drug (AOR 3.43, 95% CI: 1.00-11.74), and having comorbidities (AOR 4.94, 95% CI: 2.00-12.21). Risk factors of L. donovani complex infection included having opportunistic infection (AOR 4.22, 95% CI: 1.00-17.79), CD4 count 200-500 cells/mm3 (AOR 3.64, 95% CI: 1.14-6.86), and not using insect repellent (AOR 3.04, 95% CI: 1.08-8.58). This study identified the risk factors of Leishmania infection caused by three Leishmania species in Thailand. The data could be useful for disease prevention and control. Further studies on trends of Leishmania infection and preventive measures are recommended.


Assuntos
Infecções por HIV/epidemiologia , Leishmania/isolamento & purificação , Leishmaniose/epidemiologia , Adulto , Contagem de Linfócito CD4 , Estudos Transversais , Feminino , Humanos , Leishmania/genética , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Fatores de Risco , Saliva/parasitologia , Tailândia/epidemiologia
12.
Clin Dermatol ; 38(2): 140-151, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32513395

RESUMO

Cutaneous leishmaniasis (CL) is called "the great imitator," because it can mimic almost all types of dermatoses. This similarity may sometimes lead to misdiagnosis, resulting in inappropriate treatment and morbidities. Atypical forms occur due to the interaction between parasitic factors and the host immune response. Secondary infection or mistreatment of CL can also alter the natural course, resulting in bizarre and misdiagnosed cases. Atypical leishmaniasis should be considered in longstanding and painless lesions that may simulate erysipelas, dermatitis, verruca, herpes zoster, paronychia, and sporotrichosis. Less commonly, sarcoidosis, deep mycosis, basal and squamous cell carcinoma, cutaneous lymphoma, or pseudolymphomalike lesions may need to be considered in the differential diagnosis. A high index of suspicion is required to consider a diagnosis of CL, especially in nonendemic or newly endemic regions. Smear, histopathologic examination, culture, and polymerase chain reaction serve as important tools to differentiate CL from its clinical and histologic look-alikes. CL is discussed from various perspectives, with emphasis on CL and its broad differential diagnosis.


Assuntos
Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/patologia , Pele/patologia , Diagnóstico Diferencial , Erros de Diagnóstico , Técnicas e Procedimentos Diagnósticos , Humanos , Leishmania/genética , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Reação em Cadeia da Polimerase
13.
PLoS One ; 15(6): e0234445, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579586

RESUMO

This study aimed to describe the sand fly fauna and detect trypanosomatids in these insects from Casa Branca, state of Minas Gerais, Brazil, an endemic area of both visceral (VL) and tegumentary leishmaniasis (TL). Sand flies were collected bimonthly from May 2013 to July 2014, using automatic light traps exposed for three consecutive nights in peridomiciliary areas of nine houses with previous reports of VL and TL. ITS1-PCR and DNA sequencing were performed for trypanosomatids identification. A total of 16,771 sand flies were collected belonging to 23 species. The most abundant species was Nyssomyia whitmani (Antunes & Coutinho, 1939) (70.9%), followed by Lutzomyia longipalpis (Lutz & Neiva, 1912) (15.2%) and Migonemyia migonei (França, 1920) (9.1%). Leishmania amazonensis DNA was detected in Ny. whitmani (four pools) and Le. braziliensis DNA was detected in Psychodopygus lloydi (one pool). In seven pools of Ny. whitmani and in one pool of Lu. longipalpis positive for Leishmania DNA, the parasite species was not determined due to the low quality of the sequences. Moreover, DNA of Herpetomonas spp. was detected in Ny. whitmani (two pools) and Cortelezzii complex (one pool). DNA of Crithidia spp. was detected in Ny. whitmani and Ps. lloydi (both one pool). Our results suggest that Ny. whitmani may be involved in the transmission of Le. amazonensis in the study area. The molecular detection of Le. amazonensis suggests the presence of this species in a sylvatic cycle between vertebrate and invertebrate hosts in the region of Casa Branca. Our data also reveal the occurrence of other non-Leishmania trypanosomatids in sand flies in Casa Branca District.


Assuntos
Biodiversidade , Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Phlebotomus/parasitologia , Psychodidae/parasitologia , Animais , Brasil/epidemiologia , DNA de Protozoário/isolamento & purificação , Doenças Endêmicas/prevenção & controle , Feminino , Humanos , Leishmania/genética , Leishmaniose/epidemiologia , Leishmaniose/parasitologia , Leishmaniose/prevenção & controle , Leishmaniose/transmissão , Análise de Sequência de DNA
14.
Nucleic Acids Res ; 48(8): 4405-4417, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32232353

RESUMO

Translation of most cellular mRNAs in eukaryotes proceeds through a cap-dependent pathway, whereby the cap-binding complex, eIF4F, anchors the preinitiation complex at the 5' end of mRNAs and regulates translation initiation. The requirement of Leishmania to survive in changing environments can explain why they encode multiple eIF4E (LeishIF4Es) and eIF4G (LeishIF4Gs) paralogs, as each could be assigned a discrete role during their life cycle. Here we show that the expression and activity of different LeishIF4Es change during the growth of cultured promastigotes, urging a search for regulatory proteins. We describe a novel LeishIF4E-interacting protein, Leish4E-IP2, which contains a conserved Y(X)4LΦ IF4E-binding-motif. Despite its capacity to bind several LeishIF4Es, Leish4E-IP2 was not detected in m7GTP-eluted cap-binding complexes, suggesting that it could inhibit the cap-binding activity of LeishIF4Es. Using a functional assay, we show that a recombinant form of Leish4E-IP2 inhibits the cap-binding activity of LeishIF4E-1 and LeishIF4E-3. Furthermore, we show that transgenic parasites expressing a tagged version of Leish4E-IP2 also display reduced cap-binding activities of tested LeishIF4Es, and decreased global translation. Given its ability to bind more than a single LeishIF4E, we suggest that Leish4E-IP2 could serve as a broad-range repressor of Leishmania protein synthesis.


Assuntos
Fator de Iniciação 4F em Eucariotos/metabolismo , Leishmania/metabolismo , Proteínas de Protozoários/metabolismo , Capuzes de RNA/metabolismo , Leishmania/genética , Leishmania/crescimento & desenvolvimento , Biossíntese de Proteínas , Proteínas de Protozoários/isolamento & purificação
15.
Infect Dis Poverty ; 9(1): 30, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32183909

RESUMO

BACKGROUND: As of 2015 thousands of refugees are being hosted in temporary refugee camps in Greece. Displaced populations, travelling and living under poor conditions with limited access to healthcare are at a high risk of exposure to vector borne disease (VBD). This study sought to evaluate the risk for VBD transmission within refugee camps in Greece by analyzing the mosquito and sand fly populations present, in light of designing effective and efficient context specific vector and disease control programs. METHODS: A vector/pathogen surveillance network targeting mosquitoes and sand flies was deployed in four temporary refugee camps in Greece. Sample collections were conducted bi-weekly during June-September 2017 with the use of Centers for Disease Control (CDC) light traps and oviposition traps. Using conventional and molecular diagnostic tools we investigated the mosquito/sand fly species composition, population dynamics, pathogen infection rates, and insecticide resistance status in the major vector species. RESULTS: Important disease vectors including Anopheles sacharovi, Culex pipiens, Aedes albopictus and the Leishmania vectors Phlebotomus neglectus, P. perfiliewi and P. tobbi were recorded in the study refugee camps. No mosquito pathogens (Plasmodium parasites, flaviviruses) were detected in the analysed samples yet high sand fly Leishmania infection rates are reported. Culex pipiens mosquitoes displayed relatively high knock down resistance (kdr) mutation allelic frequencies (ranging from 41.0 to 63.3%) while kdr mutations were also detected in Ae. albopictus populations, but not in Anopheles and sand fly specimens. No diflubenzuron (DFB) mutations were detected in any of the mosquito species analysed. CONCLUSIONS: Important disease vectors and pathogens in vectors (Leishmania spp.) were recorded in the refugee camps indicating a situational risk factor for disease transmission. The Cx. pipiens and Ae. albopictus kdr mutation frequencies recorded pose a potential threat against the effectiveness of pyrethroid insecticides in these settings. In contrast, pyrethroids appear suitable for the control of Anopheles mosquitoes and sand flies and DFB for Cx. pipiens and Ae. albopictus larvicide applications. Targeted actions ensuring adequate living conditions and the establishment of integrated vector-borne disease surveillance programs in refugee settlements are essential for protecting refugee populations against VBDs.


Assuntos
Insetos Vetores/efeitos dos fármacos , Insetos Vetores/genética , Resistência a Inseticidas/genética , Leishmania , Controle de Mosquitos , Mosquitos Vetores/efeitos dos fármacos , Mosquitos Vetores/genética , Dinâmica Populacional , Campos de Refugiados , Aedes/efeitos dos fármacos , Aedes/genética , Animais , Anopheles/efeitos dos fármacos , Anopheles/genética , Culex/efeitos dos fármacos , Culex/genética , Feminino , Grécia , Leishmania/genética , Leishmania/patogenicidade , Leishmaniose/epidemiologia , Phlebotomus/efeitos dos fármacos , Phlebotomus/genética , Psychodidae
16.
Parasit Vectors ; 13(1): 132, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171322

RESUMO

BACKGROUND: Proving that specific genes are essential for the intracellular viability of Leishmania parasites within macrophages remains a challenge for the identification of suitable targets for drug development. This is especially evident in the absence of a robust inducible expression system or functioning RNAi machinery that works in all Leishmania species. Currently, if a target gene of interest in extracellular parasites can only be deleted from its genomic locus in the presence of ectopic expression from a wild type copy, it is assumed that this gene will also be essential for viability in disease-promoting intracellular parasites. However, functional essentiality must be proven independently in both life-cycle stages for robust validation of the gene of interest as a putative target for chemical intervention. METHODS: Here, we have used plasmid shuffle methods in vivo to provide supportive genetic evidence that N-myristoyltransferase (NMT) is essential for Leishmania viability throughout the parasite life-cycle. Following confirmation of NMT essentiality in vector-transmitted promastigotes, a range of mutant parasites were used to infect mice prior to negative selection pressure to test the hypothesis that NMT is also essential for parasite viability in an established infection. RESULTS: Ectopically-expressed NMT was only dispensable under negative selection in the presence of another copy. Total parasite burdens in animals subjected to negative selection were comparable to control groups only if an additional NMT copy, not affected by the negative selection, was expressed. CONCLUSIONS: NMT is an essential gene in all parasite life-cycle stages, confirming its role as a genetically-validated target for drug development.


Assuntos
Aciltransferases/genética , Genes Essenciais , Leishmania/genética , Leishmania/fisiologia , Estágios do Ciclo de Vida/genética , Proteínas de Protozoários/genética , Animais , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Genoma de Protozoário , Leishmania donovani/genética , Leishmania donovani/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Transcriptoma
17.
PLoS One ; 15(3): e0229536, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32155171

RESUMO

In this study, the presence of Leishmania DNA and blood feeding sources in phlebotomine sand fly species commonly present in Sicily were investigated. A total of 1,866 female sand flies including 176 blood fed specimens were sampled over two seasons in five selected sites in Sicily (southern Italy). Sergentomyia minuta (n = 1,264) and Phlebotomus perniciousus (n = 594) were the most abundant species at all the sites, while three other species from the genus Phlebotomus (i.e., P. sergenti n = 4, P. perfiliewi n = 3 and P. neglectus n = 1) were only sporadically captured. Twenty-eight out of the 1,866 (1.5%) sand flies tested positive for Leishmania spp. Leishmania tarentolae DNA was identified in 26 specimens of S. minuta, while the DNA of Leishmania donovani complex was detected in a single specimen each of S. minuta and P. perniciosus. Interestingly, seven S. minuta specimens (0.4%) tested positive for reptilian Trypanosoma sp. Blood sources were successfully identified in 108 out of 176 blood fed females. Twenty-seven out of 82 blood sources identified in fed females of P. perniciosus were represented by blood of wild rabbit, S. minuta mainly fed on humans (16/25), while the sole P. sergenti fed specimen took a blood meal on rat. Other vertebrate hosts including horse, goat, pig, dog, chicken, cow, cat and donkey were recognized as blood sources for P. perniciosus and S. minuta, and, surprisingly, no reptilian blood was identified in blood-fed S. minuta specimens. Results of this study agree with the well-known role of P. perniciosus as vector of L. infantum in the western Mediterranean; also, vector feeding preferences herein described support the hypothesis on the involvement of lagomorphs as sylvatic reservoirs of Leishmania. The detection of L. donovani complex in S. minuta, together with the anthropophilic feeding-behaviour herein observed, warrants further research to clarify the capacity of this species in the transmission of pathogens to humans and other animals.


Assuntos
Psychodidae/genética , Psychodidae/patogenicidade , Animais , DNA/genética , Comportamento Alimentar , Insetos Vetores , Leishmania/genética , Psychodidae/classificação , Estações do Ano , Sicília , Especificidade da Espécie , Trypanosomatina/genética
18.
J Immunol ; 204(7): 1869-1880, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32132181

RESUMO

Leishmaniases are neglected tropical diseases. The treatment of leishmaniasis relies exclusively on chemotherapy including amphotericin B (AmB), miltefosine (hexadecylphosphocholine), and pentamidine. Besides the fact that these molecules are harmful for patients, little is known about the impact of such antileishmanial drugs on primary human cells in relation to immune function. The present study demonstrates that all antileishmanial drugs inhibit CD4 and CD8 T cell proliferation at the doses that are not related to increased cell death. Our results highlight that antileishmanial drugs have an impact on monocytes by altering the expression of IL-12 induced by LPS, whereas only AmB induced IL-10 secretion; both cytokines are essential in regulating Th1 cell-mediated immunity. Interestingly, IL-12 and anti-IL-10 Abs improved T cell proliferation inhibited by AmB. Furthermore, our results show that in contrast to hexadecylphosphocholine and pentamidine, AmB induced gene expression of the inflammasome pathway. Thus, AmB induced IL-1ß and IL-18 secretions, which are reduced by specific inhibitors of caspase activation (Q-VD) and NLRP3 activation (MCC950). Our results reveal previously underestimated effects of antileishmanial drugs on primary human cells.


Assuntos
Antiparasitários/farmacologia , Inflamassomos/efeitos dos fármacos , Interleucina-12/metabolismo , Leishmania/genética , Leishmaniose/tratamento farmacológico , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Humanos , Inflamassomos/metabolismo , Interleucina-10/metabolismo , Leishmania/metabolismo , Leishmaniose/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Mem Inst Oswaldo Cruz ; 115: e190284, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049097

RESUMO

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.


Assuntos
Insetos Vetores/parasitologia , Leishmania/classificação , Psychodidae/parasitologia , Animais , DNA de Protozoário/genética , Leishmania/genética , Leishmaniose/transmissão , Reação em Cadeia da Polimerase
20.
BMC Infect Dis ; 20(1): 163, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087701

RESUMO

BACKGROUND: American tegumentary leishmaniasis (ATL) is a widespread anthropozoonosis caused by protozoa of the genus Leishmania and is considered a serious public health problem. The aim of this study was to provide a descriptive analysis of confirmed ATL cases and evaluate the spatial distribution of ATL in high-risk transmission areas from the state of Minas Gerais, Brazil. METHODS: An ecological, analytical, and retrospective study of the confirmed cases of ATL in Minas Gerais from 2007 to 2017 was conducted. To characterize these cases, multiple correspondence analysis and georeferencing of the ATL prevalence rates in the municipalities were conducted based on variables obtained at Sistema Nacional de Agravos de Notificação and Instituto Brasileiro de Geografia e Estatística databases. RESULTS: There were 13,025 confirmed cases of ATL from 74.4% (635) municipalities of Minas Gerais, corresponding to a prevalence rate of 66.5 cases for every 100,000 inhabitants. Males aged 20 to 59 years and individuals who attended elementary school were most affected with ATL. Multiple correspondence analysis presented an accumulated qui-squared value of 44.74%, proving that there was a relationship between the variables, including ethnicity, age, pregnancy status, zone of infection, and number of cases. CONCLUSION: We confirmed that ATL is endemic to Minas Gerais, and there is high risk of infection within the municipalities due to a high rate of parasite transmission. The occurrence of infection in children, pregnant women, and the indigenous population demonstrates the need for the government to expand social policies aimed at vulnerable groups.


Assuntos
Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/transmissão , Adolescente , Adulto , Brasil/epidemiologia , Criança , Pré-Escolar , Cidades/epidemiologia , Doenças Endêmicas , Feminino , Humanos , Lactente , Leishmania/genética , Leishmania/imunologia , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Gravidez , Prevalência , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
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