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1.
BMC Infect Dis ; 12: 191, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22894734

RESUMO

BACKGROUND: The diagnosis of the leishmaniases poses enormous challenges in Argentina. The Polymorphism-Specific PCR (PS-PCR) designed and validated in our laboratories has been proven effective for typifying the Leishmania genus from cultured material. Here we evaluated the performance of this method in the diagnosis of American tegumentary leishmaniasis (ATL) and the rapid identification of Leishmania spp. directly from clinical specimens. METHODS: A total of 63 patients from northwestern Argentina, with cutaneous or mucocutaneous lesions, underwent an ATL diagnosis protocol which included clinical examination, Leishmanin skin test, and microscopic examination of dermal smears. In addition, we performed PS-PCR on DNA directly extracted from the specimens scraped from the lesions. RESULTS: Out of the 63 patients, 44 were classified as ATL cases and 19 as non-ATL cases. The diagnostic sensitivity of the microscopic analysis of dermal smears and PS-PCR individually were 70.5% and 81%, respectively. When performing both tests in parallel, this parameter increased significantly to 97.6% (p = 0.0018). The specificities, on the other hand, were 100%, 84.2%, and 83.3% for the combination, respectively (p > 0.05). Using the PS-PCR analysis we successfully identified the Leishmania spp. in 31 out of the 44 ATL cases. Twenty-eight (90.3%) cases were caused by L. (V.) braziliensis, two (6.5%) by L. (V.) guyanensis, and one (3.2%) by L. (V.) panamensis. CONCLUSIONS: The efficacy of the ATL diagnosis was significantly improved by combining the dermal smear examination with a PS-PCR analysis. Our strategy allowed us to reach the diagnosis of ATL with high accuracy regarding the species of the etiological agent in 70.5% of the cases. Moreover, we diagnosed two cases of the disseminated cutaneous form caused by L. (V.) braziliensis and a cutaneous case due to L. (V.) panamensis infection, both findings reported for the first time in Argentina.


Assuntos
Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Parasitologia/métodos , Reação em Cadeia da Polimerase/métodos , Adulto , Argentina , Feminino , Humanos , Leishmania/genética , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
2.
J Clin Microbiol ; 48(10): 3661-5, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20720027

RESUMO

The FTA card (Whatman) was assessed for its utility as a molecular epidemiological tool in collecting samples from patients with leishmaniasis in Peru because the card has a variety of merits; it is less invasive for patients and easy to handle for both physicians and other medical personnel for sample collection or diagnosis, in addition to its simplicity and easy countrywide and/or intercountry transportation for analysis. Samples were collected from 132 patients suspected of having leishmaniasis, and Leishmania species were successfully identified in samples from 81 patients in 15 departments of Peru by cytochrome b and mannose phosphate isomerase gene analyses. Of these, 61.7% were identified as Leishmania (Viannia) peruviana, 22.2% as L. (V.) braziliensis, 12.3% as L. (V.) guyanensis, 2.5% as L. (V.) shawi, and 1.2% as L. (V.) lainsoni. The three predominant species, L. (V.) peruviana, L. (V.) braziliensis, and L. (V.) guyanensis, were mainly found in the Andean highlands, in the tropical rainforest, and in northern and central rainforest regions, respectively. This is the first time L. (V.) shawi has been identified outside Brazil. The present study showed that the FTA card will be a useful tool for the ecological study of different forms of leishmaniasis. Furthermore, collecting samples directly from patients' lesions by using the FTA card eliminates (i) the possibility of contamination of Leishmania isolates during short- and/or long-term passages of culture in vitro in each laboratory and (ii) pain and suffering of patients from taking samples by skin biopsy.


Assuntos
Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/patologia , Parasitologia/métodos , Manejo de Espécimes/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Citocromos b/genética , Feminino , Humanos , Lactente , Recém-Nascido , Leishmania/genética , Masculino , Manose-6-Fosfato Isomerase/genética , Pessoa de Meia-Idade , Peru , Proteínas de Protozoários/genética , Adulto Jovem
3.
Acta Trop ; 203: 105287, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31790649

RESUMO

By employing protected human bait landing and modified Shannon light trap, a total of 1924 phlebotomine sand fly Lutzomyia spp. were captured in an area from which L. (V.) guyanensis was reported as the causative parasite of cutaneous leishmaniasis (CL). The sand flies captured alive were dissected and identified at species level, based mainly on their spermathecae. At the same time, the sand flies dissected were searched for the Leishmania parasites by microscopic-test, and later on by PCR-test. No positive sand flies were detected by both tests, while considerable numbers of anthropophilic sand fly species of the genus Lutzomyia were observed as probable vectors of the Leishmania parasite in the areas. Those were eight species, Lu. robusta, Lu. trapidoi, Lu. maranonensis, Lu. gomezi, Lu. shannoni, Lu. migonei, Lu. punctigeniculata and Lu. spathotrichia. Among them, the first two species Lu. robusta and Lu. trapidoi were most dominant, suggesting probable vectors of the Leishmania parasite prevailing in the area. Lu. punctigeniculata and Lu. spathotrichia were for the first time recorded for the Manabí province, Ecuador. These findings provide basic information useful for future planning of the control and management of the disease in the areas, though further study to incriminate the vector sand fly remains.


Assuntos
Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Phlebotomus/parasitologia , Animais , Equador/epidemiologia , Humanos , Leishmaniose Cutânea/transmissão
4.
Exp Parasitol ; 121(4): 352-61, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19159626

RESUMO

In a previous report (Luyo-Acero et al., 2004), we demonstrated that cytochrome b (Cyt b) gene analysis is an effective method for classifying several isolates of the genus Leishmania; hence, we have further applied this method to other Leishmania species in an effort to enhance the accuracy of the procedure and to construct a new phylogenic tree. In this study, a total of 30 Leishmania and Endotrypanum WHO reference strains, clinical isolates from our patients assigned to 28 strains (human and non-human pathogenic species) and two species of the genus Endotrypanum were analyzed. The Cyt b gene in each sample was amplified by PCR, and was then sequenced by several primers, as reported previously. The phylogenic tree was constructed based on the results obtained by the computer software MEGA v3.1 and PAUP* v4.0 Beta. The present phylogenic tree was almost identical to the traditional method of classification proposed by Lainson and Shaw (1987). However, it produces the following suggestions: (1) exclusion of L. (Leishmania) major from the L. (L.) tropica complex; (2) placement of L.tarentolae in the genus Sauroleishmania; (3) L. (L.) hertigi complex and L. (V.) equatorensis close to the genus Endotrypanum; (4) L. (L.) enrietti, defined as L. (L.) mexicana complex, placed in another position; and (5) L. (L.) turanica and L. (L.) arabica are located in an area far from human pathogenic Leishmania strains. Cyt b gene analysis is thus applicable to the analyzing phylogeny of the genus Leishmania and may be useful for separating non-human pathogenic species from human pathogenic species.


Assuntos
Citocromos b/genética , DNA de Protozoário/química , Leishmania/classificação , Filogenia , Animais , Sequência de Bases , Sequência Consenso , Humanos , Leishmania/enzimologia , Leishmania/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Trypanosomatina/classificação , Trypanosomatina/genética
5.
Acta Trop ; 178: 264-275, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29224978

RESUMO

The vector Lutzomyia sand flies and reservoir host mammals of the Leishmania parasites, causing the Andean cutaneous leishmaniasis (Andean-CL, uta) in Peru and Ecuador were thoroughly reviewed, performing a survey of literatures including our unpublished data. The Peruvian L. (V.) peruviana, a principal Leishmania species causing Andean-CL in Peru, possessed three Lutzomyia species, Lu. peruensis, Lu. verrucarum and Lu. ayacuchensis as vectors, while the Ecuadorian L. (L.) mexicana parasite possessed only one species Lu. ayacuchensis as the vector. Among these, the Ecuadorian showed a markedly higher rate of natural Leishmania infections. However, the monthly and diurnal biting activities were mostly similar among these vector species was in both countries, and the higher rates of infection (transmission) reported, corresponded to sand fly's higher monthly-activity season (rainy season). The Lu. tejadai sand fly participated as a vector of a hybrid parasite of L. (V.) braziliensis/L. (V.) peruviana in the Peruvian Andes. Dogs were considered to be principal reservoir hosts of the L. (V.) peruviana and L. (L.) mexicana parasites in both countries, followed by other sylvatic mammals such as Phyllotis andium, Didelphis albiventris and Akodon sp. in Peru, and Rattus rattus in Ecuador, but information on the reservoir hosts/mammals was extremely poor in both countries. Thus, the Peruvian disease form demonstrated more complicated transmission dynamics than the Ecuadorian. A brief review was also given to the control of vector and reservoirs in the Andes areas. Such information is crucial for future development of the control strategies of the disease.


Assuntos
Reservatórios de Doenças/parasitologia , Insetos Vetores/parasitologia , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Mamíferos/parasitologia , Psychodidae/parasitologia , Animais , Equador/epidemiologia , Humanos , Peru/epidemiologia , Estações do Ano
6.
Acta Trop ; 177: 135-145, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29017878

RESUMO

This study provides comprehensive information on the past and current status of the Andean cutaneous leishmaniasis (Andean-CL, uta) in Peru and Ecuador, mainly focusing on the causative Leishmania parasites and clinico-epidemiological features. Available information and data including our unpublished works were analyzed thoroughly. Endemic regions of the Andean-CL (uta) in Peru run from the north Piura/Cajamarca to the south Ayacucho at a wide range of the Pacific watersheds of the Andes through several departments, while in Ecuador those exist at limited and spotted areas in the country's mid-southwestern two provinces, Azuay and Chimborazo. The principal species of the genus Leishmania are completely different at subgenus level, L. (Viannia) peruviana in Peru, and L. (Leishmania) mexicana and L. (L.) major-like (infrequent occurrence) in Ecuador. The Peruvian uta is now prevalent in different age and sex groups, being not clearly defined as found in the past. The precise reasons are not known and should be elucidated further, though probable factors, such as emergence of other Leishmania parasites, non-immune peoples' migration into the areas, etc., were discussed briefly in the text. The Andean-CL cases in Ecuador are more rural than before, probably because of a rapid development of the Leishmania-positive communities and towns, and the change of life-styles of the inhabitants, including newly constructed houses and roads in the endemic areas. Such information is helpful for future management of the disease, not only for Leishmania-endemic areas in the Andes but also for other endemic areas.


Assuntos
Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Psychodidae/parasitologia , Animais , Equador/epidemiologia , Feminino , Geografia , Humanos , Masculino , Peru/epidemiologia
7.
Am J Trop Med Hyg ; 77(4): 640-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17978064

RESUMO

Azithromycin was compared with meglumine antimoniate for treatment of patients with cutaneous leishmaniasis. Patients were randomized to receive oral azithromycin, 500 mg/day (22 patients) or intramuscular meglumine antimoniate, 10 mg Sb/kg/day (23 patients), both for 28 days, with a second cycle of 15 days if necessary, and followed-up for one year after completion of treatment. Efficacy, defined as complete re-epithelization without relapse for 12 months after completing therapy, was 82.6% (95% confidence interval [CI] = 67-98%) for meglumine antimoniate and 45.5% (95% CI = 25-66%) for azithromycin. All patients who failed treatment with azithromycin were treated with meglumine antimoniate and clinically cured. Azithromycin was well tolerated; meglumine antimoniate caused arthralgias and local symptoms in 78% of the patients. In 17 cases, species identification was obtained; Leishmania (Viannia) braziliensis was identified in all of them. For the treatment of American cutaneous leishmaniasis caused by L. (V.) braziliensis, meglumine antimoniate is significatively more efficacious than azithromycin, which was clinically curative in almost half of the patients and well-tolerated.


Assuntos
Azitromicina/administração & dosagem , Leishmania braziliensis/crescimento & desenvolvimento , Leishmaniose Cutânea/tratamento farmacológico , Meglumina/administração & dosagem , Compostos Organometálicos/administração & dosagem , Administração Oral , Adulto , Animais , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Antiprotozoários/administração & dosagem , Antiprotozoários/efeitos adversos , Argentina/epidemiologia , Azitromicina/efeitos adversos , Doenças Endêmicas , Feminino , Humanos , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Masculino , Meglumina/efeitos adversos , Antimoniato de Meglumina , Pessoa de Meia-Idade , Compostos Organometálicos/efeitos adversos
8.
Acta Trop ; 166: 299-315, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27919688

RESUMO

This article reviews current knowledge about leishmaniases in Ecuador, proceeding from 1920, when the first human case was described, to the present, mainly focusing on the recent research events published. Regarding basic situations, it appears that 23 of Ecuador's 24 provinces have leishmaniasis-case reports. The disease is one of the mandatory notification infectious diseases in the country since 2005. All the 21,305 cases notified to the Ministry of Public Health, during the period from 2001 through 2014, were said to involve different clinical features of cutaneous leishmaniasis (CL) but not visceral (VL). Eight Leishmania species, L. (Viannia) guyanensis, L. (V.) panamensis, L. (V.) braziliensis, L. (Leishmania) mexicana, L. (L.) amazonensis, L. (L.) major-like, L. (V.) naiffiand L. (V.) lainsoni were characterized. The last two species were most recently reported from the Ecuadorian Amazon regions. Of the 73 Ecuadorian Lutzomyia species (43 man-biting species) recorded, only four, Lu. trapidoi, Lu. gomezi, Lu. ayacuchensis, and Lu. tortura were incriminated as vectors of the Leishmania parasites. Current knowledge on the reservoir hosts of Leishmania in Ecuador is extremely poor. Recently, in Ecuador different kinds of molecular techniques were developed for diagnosis and mass screening of the disease, employing various materials derived from patients and sand fly vectors. These are PCR-RFLP, colorimetric FTA-LAMP etc. Brief comments and recommendations were also given, for future research and control of leishmaniases in Ecuador.


Assuntos
Insetos Vetores/parasitologia , Leishmania , Leishmaniose Cutânea/epidemiologia , Psychodidae/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Equador/epidemiologia , Feminino , Humanos , Lactente , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/transmissão , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Adulto Jovem
9.
Am J Trop Med Hyg ; 75(2): 256-60, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16896128

RESUMO

Recently, two techniques, polymerase chain reaction (PCR) amplification and sequencing of cytochrome b gene (cyt b gene sequencing) and polymorphism-specific PCR (PS-PCR) were recommended for Leishmania species identification. Before this study, however, the accuracy of these methods had not been tested against the multilocus enzyme electrophoresis, the current gold standard technique on this task. Therefore, a trial was done for the first time to compare the results obtained by these techniques, using 17 Argentinean Leishmania stocks in independent assays. For all the stocks examined, the same results at species level were obtained by the three techniques. Among them, 14 were assigned to L. (Viannia) braziliensis, and three to L. (V.) guyanensis. The two techniques, cyt b gene sequencing and PS-PCR, were able to distinguish between all the proven species responsible for leishmaniases in Argentina. Thus, both techniques were validated and could be used independently for the species designation of Leishmania parasites in the country.


Assuntos
Citocromos b/genética , Leishmania/classificação , Reação em Cadeia da Polimerase/normas , Animais , Argentina , Sequência de Bases , Primers do DNA/química , Método Duplo-Cego , Eletroforese em Gel de Ágar , Leishmania/enzimologia , Leishmania/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético , Reprodutibilidade dos Testes , Alinhamento de Sequência/métodos , Especificidade da Espécie
10.
BMC Infect Dis ; 6: 139, 2006 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-16968553

RESUMO

BACKGROUND: Determinants of the clinical presentation of the leishmaniases are poorly understood but Leishmania species and strain differences are important. To examine the relationship between clinical presentation, species and isoenzyme polymorphisms, 56 Leishmania isolates from distinct presentations of American tegumentary leishmaniasis (ATL) from Ecuador were analyzed. METHODS: Isolates were characterized by multilocus enzyme electrophoresis for polymorphisms of 11 isoenzymes. Patients were infected in four different ecologic regions: highland and lowland jungle of the Pacific coast, Amazonian lowlands and Andean highlands. RESULTS: Six Leishmania species constituting 21 zymodemes were identified: L. (Viannia) panamensis (21 isolates, 7 zymodemes), L. (V.) guyanensis (7 isolates, 4 zymodemes), L. (V.) braziliensis (5 isolates, 3 zymodemes), L. (Leishmania) mexicana (11 isolates, 4 zymodemes), L. (L.) amazonensis (10 isolates, 2 zymodemes) and L. (L.) major (2 isolates, 1 zymodeme). L. panamensis was the species most frequently identified in the Pacific region and was associated with several clinical variants of cutaneous disease (CL); eight cases of leishmaniasis recidiva cutis (LRC) found in the Pacific highlands were associated with 3 zymodemes of this species. Mucocutaneous leishmaniasis found only in the Amazonian focus was associated with 3 zymodemes of L. braziliensis. The papular variant of CL, Uta, found in the Andean highlands was related predominantly with a single zymodeme of L. mexicana. CONCLUSION: Our data show a high degree of phenotypic variation within species, and some evidence for associations between specific variants of ATL (i.e. Uta and LRC) and specific Leishmania zymodemes. This study further defines the geographic distribution of Leishmania species and clinical variants of ATL in Ecuador.


Assuntos
Isoenzimas/genética , Leishmania/enzimologia , Leishmaniose Cutânea/parasitologia , Adulto , Animais , Criança , Pré-Escolar , Equador , Feminino , Humanos , Leishmania/genética , Leishmania/isolamento & purificação , Masculino , Polimorfismo Genético
11.
PLoS Negl Trop Dis ; 10(7): e0004844, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27410039

RESUMO

A countrywide epidemiological study was performed to elucidate the current geographic distribution of causative species of cutaneous leishmaniasis (CL) in Ecuador by using FTA card-spotted samples and smear slides as DNA sources. Putative Leishmania in 165 samples collected from patients with CL in 16 provinces of Ecuador were examined at the species level based on the cytochrome b gene sequence analysis. Of these, 125 samples were successfully identified as Leishmania (Viannia) guyanensis, L. (V.) braziliensis, L. (V.) naiffi, L. (V.) lainsoni, and L. (Leishmania) mexicana. Two dominant species, L. (V.) guyanensis and L. (V.) braziliensis, were widely distributed in Pacific coast subtropical and Amazonian tropical areas, respectively. Recently reported L. (V.) naiffi and L. (V.) lainsoni were identified in Amazonian areas, and L. (L.) mexicana was identified in an Andean highland area. Importantly, the present study demonstrated that cases of L. (V.) braziliensis infection are increasing in Pacific coast areas.


Assuntos
Citocromos b , Leishmania/genética , Leishmaniose/epidemiologia , Leishmaniose/parasitologia , Equador , Regulação da Expressão Gênica , Humanos , Filogenia
12.
PLoS Negl Trop Dis ; 10(5): e0004728, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27191391

RESUMO

An epidemiological study of leishmaniasis was performed in Amazonian areas of Ecuador since little information on the prevalent Leishmania and sand fly species responsible for the transmission is available. Of 33 clinical specimens from patients with cutaneous leishmaniasis (CL), causative parasites were identified in 25 samples based on cytochrome b gene analysis. As reported previously, Leishmania (Viannia) guyanensis and L. (V.) braziliensis were among the causative agents identified. In addition, L. (V.) lainsoni, for which infection is reported in Brazil, Bolivia, Peru, Suriname, and French Guiana, was identified in patients with CL from geographically separate areas in the Ecuadorian Amazon, corroborating the notion that L. (V.) lainsoni is widely distributed in South America. Sand flies were surveyed around the area where a patient with L. (V.) lainsoni was suspected to have been infected. However, natural infection of sand flies by L. (V.) lainsoni was not detected. Further extensive vector searches are necessary to define the transmission cycle of L. (V.) lainsoni in Ecuador.


Assuntos
Insetos Vetores/parasitologia , Leishmaniose Cutânea/epidemiologia , Psychodidae/parasitologia , Animais , Citocromos b/genética , Equador/epidemiologia , Feminino , Humanos , Leishmania/classificação , Leishmania/genética , Leishmania/isolamento & purificação , Leishmania guyanensis/genética , Leishmania guyanensis/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/transmissão , Masculino , Filogenia , Reação em Cadeia da Polimerase , Pele/parasitologia , América do Sul/epidemiologia
13.
Acta Trop ; 153: 116-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26516109

RESUMO

Leishmaniasis remains one of the world's most neglected diseases, and early detection of the infectious agent, especially in developing countries, will require a simple and rapid test. In this study, we established a quick, one-step, single-tube, highly sensitive loop-mediated isothermal amplification (LAMP) assay for rapid detection of Leishmania DNA from tissue materials spotted on an FTA card. An FTA-LAMP with pre-added malachite green was performed at 64°C for 60min using a heating block and/or water bath and DNA amplification was detected immediately after incubation. The LAMP assay had high detection sensitivity down to a level of 0.01 parasites per µl. The field- and clinic-applicability of the colorimetric FTA-LAMP assay was demonstrated with 122 clinical samples collected from patients suspected of having cutaneous leishmaniasis in Peru, from which 71 positives were detected. The LAMP assay in combination with an FTA card described here is rapid and sensitive, as well as simple to perform, and has great potential usefulness for diagnosis and surveillance of leishmaniasis in endemic areas.


Assuntos
Colorimetria/métodos , Leishmania/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Programas de Rastreamento/métodos , Corantes de Rosanilina/análise , Adulto , Feminino , Humanos , Masculino , Técnicas de Amplificação de Ácido Nucleico , Peru , Sensibilidade e Especificidade
14.
Am J Trop Med Hyg ; 72(1): 87-93, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15728872

RESUMO

The surveillance of prevalent Leishmania and sand fly species in endemic areas is important for prediction of the risk and expansion of leishmaniasis. In this study, we developed a polymerase chain reaction (PCR)-based method for detection of Leishmania minicircle DNA within individual sand flies. Using this method, we detected minicircle DNA in 6 (3.3%) of 183 sand flies, while 5 (3.5%) of 143 were positive for Leishmania promastigotes in the same areas by microscopic examination. The species were identified as Leishmania (Leishmania) mexicana by nucleotide sequencing of the cytochrome b gene. Additionally, all the Leishmania-positive sand flies were identified as Lutzomyia ayacuchensis by the restriction enzyme digestion of the PCR-amplified 18S ribosomal RNA gene fragments. Since this combined method is relatively easy and can process a large number of samples, it will be a powerful tool for the rapid identification of prevalent sand fly and Leishmania species as well as monitoring the infection rate in sand fly populations in endemic areas.


Assuntos
DNA de Cinetoplasto/análise , DNA de Protozoário/análise , Leishmania/isolamento & purificação , Psychodidae/parasitologia , RNA Ribossômico 18S/análise , Animais , DNA de Cinetoplasto/genética , DNA de Protozoário/genética , Equador , Insetos Vetores/parasitologia , Leishmania/classificação , Leishmania/genética , Leishmaniose/transmissão , Reação em Cadeia da Polimerase/métodos
15.
Acta Trop ; 141(Pt A): 79-87, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25312337

RESUMO

Haplotype and gene network analyses were performed on mitochondrial cytochrome oxidase I and cytochrome b gene sequences of Lutzomyia (Lu.) ayacuchensis populations from Andean areas of Ecuador and southern Peru where the sand fly species transmit Leishmania (Leishmania) mexicana and Leishmania (Viannia) peruviana, respectively, and populations from the northern Peruvian Andes, for which transmission of Leishmania by Lu. ayacuchensis has not been reported. The haplotype analyses showed higher intrapopulation genetic divergence in northern Peruvian Andes populations and less divergence in the southern Peru and Ecuador populations, suggesting that a population bottleneck occurred in the latter populations, but not in former ones. Importantly, both haplotype and phylogenetic analyses showed that populations from Ecuador consisted of clearly distinct clusters from southern Peru, and the two populations were separated from those of northern Peru.


Assuntos
Filogenia , Psychodidae/genética , Animais , Sequência de Bases , Citocromos b/genética , Equador , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética/genética , Haplótipos , Humanos , Insetos Vetores/genética , Leishmania , Leishmania mexicana , Leishmaniose Cutânea/transmissão , Peru , Psychodidae/parasitologia
16.
Biochimie ; 112: 49-56, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25724270

RESUMO

Sequence analysis of the Lutzomyia (Lu.) ayacuchensis salivary gland cDNA library identified a short peptide containing an RGD (Arg-Gly-Asp) sequence flanked by two cysteine residues in the C-terminal end as the most abundant transcript. In the present study, a recombinant protein of the RGD-containing peptide, designated ayadualin, was expressed in Escherichia coli and its activity was characterized. Ayadualin inhibited both collagen and ADP-induced platelet aggregations by interfering with the binding of integrin αIIbß3 to fibrinogen. The RGD sequence and cysteine residues located on both sides of the RGD sequence were essential for the inhibitory action. Moreover, ayadualin efficiently inhibited the intrinsic blood coagulation pathway irrespective of the RGD sequence. Measuring the enzymatic activity of coagulation factors using chromogenic substrates revealed that ayadualin efficiently inhibited factor XIIa (FXIIa) activity in a dose-dependent manner. In addition, pre-incubation of ayadualin with FXII inhibited FXIIa activity, while activated FXIIa was not affected by ayadualin, indicating that ayadualin inhibits the activation of FXII, but not enzymatic activity of FXIIa. These results indicated that ayadualin plays an important role in the blood feeding of Lu. ayacuchensis by inhibiting host hemostasis via dual mechanisms.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Fator XIIa/antagonistas & inibidores , Proteínas de Insetos/farmacologia , Insetos Vetores/química , Leishmaniose Cutânea , Oligopeptídeos/farmacologia , Psychodidae/química , Animais , Relação Dose-Resposta a Droga , Humanos , Proteínas de Insetos/química , Oligopeptídeos/química
17.
Am J Trop Med Hyg ; 93(2): 334-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26055744

RESUMO

Cases of human visceral leishmaniasis (HVL) were not recorded until recently in the Chaco region of northwestern Argentina. Dogs were surveyed at the sites of infection of two HVL index cases in the Chaco region of Salta province. Canine cases (CanL) were diagnosed by two parasitological methods, two molecular methods targeting mini- and maxicircle DNA, and immunochromatographic dipstick. Among 77 dogs studied, 10 (13%) were found infected with Leishmania spp. In seven dogs and two humans, the infecting species was typed as Leishmania (Leishmania) infantum. The same genotype was detected in the human and two of the CanL. Although several diagnostic methods displayed weak or moderate agreement, the concordance values for serology versus maxicircle PCR were very good (Kappa index = 0.84). Sandflies captured in the area were identified as Lutzomyia migonei and Lu. cortelezzii/Lu. sallesi (cortelezzii complex). The focal appearance of leishmaniasis in dogs and humans in a sylvatic region and its relatively low prevalence of infection suggests that L. (L.) infantum transmission to dogs and humans may, in this region, stem from sylvatic reservoirs.


Assuntos
Doenças do Cão/epidemiologia , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Adulto , Animais , Argentina/epidemiologia , Citocromos b/genética , DNA de Protozoário/isolamento & purificação , Doenças do Cão/parasitologia , Cães , Feminino , Genótipo , Humanos , Lactente , Insetos Vetores/parasitologia , Leishmania infantum/genética , Masculino , Reação em Cadeia da Polimerase/veterinária , Prevalência , Psychodidae/parasitologia
18.
FEBS Lett ; 529(2-3): 319-24, 2002 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-12372621

RESUMO

Identification of physiological substrates for Cdc2/cyclin B is crucial for understanding the functional link between mitotic events and Cdc2/cyclin B activation. A human homologue of the Drosophila warts tumor suppressor, termed WARTS, is a serine/threonine kinase and a dynamic component of the mitotic apparatus. We have found that Cdc2/cyclin B forms a complex with a fraction of WARTS in the centrosome and phosphorylates the Ser613 site of WARTS during mitosis. Immunocytochemical analysis has shown that the S613-phosphorylated WARTS appears in the spindle poles at prometaphase and disappears at telophase. Our findings suggest that Cdc/cyclin B regulates functions of WARTS on the mitotic apparatus.


Assuntos
Proteína Quinase CDC2/metabolismo , Ciclina B/metabolismo , Proteínas de Drosophila , Genes Supressores de Tumor , Mitose , Proteínas Quinases , Proteínas Serina-Treonina Quinases/metabolismo , Fuso Acromático , Sequência de Aminoácidos , Western Blotting , Cromatografia em Gel , Células HeLa , Humanos , Microscopia de Fluorescência , Fosforilação , Testes de Precipitina , Proteínas Serina-Treonina Quinases/imunologia , Frações Subcelulares/metabolismo , Especificidade por Substrato
19.
Parasitol Int ; 53(4): 337-44, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15464443

RESUMO

Isozyme analysis with 18 enzyme loci was conducted on 146 isolates of Trypanosoma cruzi from Mexico, Guatemala, Colombia, Ecuador, Peru, Brazil, Bolivia, Paraguay and Chile. Forty-four different MLGs (groups of isolates with identical multilocus genotypes) were identified and a phylogeny was constructed. The phylogenetic tree consisted of two main groups (T. cruzi I, T. cruzi II), and the latter was further divided into two subgroups (T. cruzi IIa, T. cruzi IIb-e). Evidence of hybridization between different MLGs of T. cruzi II was found, which means that genetic exchanges seem to have occurred in South American T. cruzi. On the other hand, the persistence of characteristic T. cruzi I and T. cruzi II isozyme patterns in single small villages in Bolivia and Guatemala suggested that genetic exchange is very rare between major lineages. A significant difference in genetic diversity was shown between T. cruzi I and T. cruzi II from several indices of population genetics. Two possibilities could explain this genetic variation in the population: differences in evolutionary history and/or different tendencies to exchange genetic material. Broad-scale geographic distributions of T. cruzi I and T. cruzi IIb-e were different; T. cruzi I occurred in Central America and south to Bolivia and Brazil, while T. cruzi IIb-e occurred in the central and southern areas of South America, overlapping with T. cruzi I in Brazil and Bolivia.


Assuntos
Doença de Chagas/epidemiologia , Variação Genética , Filogenia , Trypanosoma cruzi/classificação , Animais , Doença de Chagas/parasitologia , DNA de Protozoário/análise , Genótipo , Guatemala/epidemiologia , Humanos , Isoenzimas/genética , México/epidemiologia , América do Sul/epidemiologia , Triatoma/parasitologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/patogenicidade
20.
J Vet Med Sci ; 65(5): 649-53, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12808222

RESUMO

PCR amplification and nucleotide sequencing of the mini-exon gene revealed that four strains isolated from a sloth (Choloepus hoffmanni), a squirrel (Sciurus granatensis) and two sandflies (Lutzomyia hartmanni) in Ecuador were indistinguishable from Endotrypanum monterogeii. Another strain isolated from Lu. hartmanni showed the high sequence similarity to E. schaudinni. Since three of these strains have been previously identified as Leishmania (Viannia) equatorensis, the results demonstrate that L. (V.) equatorensis is genetically closely related to the genus Endotrypanum. The present study also indicates that Endotrypanum species are distributed in arboreal animals and sandflies in Ecuador, and that mini-exon gene amplification is useful for epidemiological studies of Leishmania and Endotrypanum in the New World.


Assuntos
Éxons/genética , Psychodidae/parasitologia , Sciuridae/parasitologia , Bichos-Preguiça/parasitologia , Trypanosomatina/classificação , Trypanosomatina/genética , Animais , Sequência de Bases , Equador , Íntrons/genética , Leishmania/classificação , Leishmania/genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Infecções por Protozoários/diagnóstico , Infecções Protozoárias em Animais , Alinhamento de Sequência , Especificidade da Espécie
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