Laboratorio Of Entomologia Medica

Porto Velho, Brazil

Laboratorio Of Entomologia Medica

Porto Velho, Brazil

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Carvalho I.M.,Instituto Butantan | Moraes R.B.,Laboratorio Of Entomologia Medica | Gil H.B.,University of Sao Paulo | Alves R.,University of Sao Paulo | And 3 more authors.
Revista da Sociedade Brasileira de Medicina Tropical | Year: 2014

Introduction: Microsporidia constitute the most common black fl y pathogens, although the species’ diversity, seasonal occurrence and transmission mechanisms remain poorly understood. Infections by this agent are often chronic and non-lethal, but they can cause reduced fecundity and decreased longevity. The objective of this study was to identify microsporidia infecting Simulium (Chirostilbia) pertinax (Kollar, 1832) larvae from Caraguatatuba, State of São Paulo, Brazil, by molecular and morphological characterization. Methods: Larvae were collected at a single point in a stream in a rural area of the city and were kept under artificial aeration until analysis. Polydispyrenia spp. infection was characterized by the presence of at least 32 mononuclear spores measuring 6.9 ± 1.0 x 5.0 ± 0.7µm in persistent sporophorous vesicles. Similarly, Amblyospora spp. were characterized by the presence of eight uninucleate spores measuring 4.5 x 3.5µm in sporophorous vesicles. Results: The molecular analysis confirmed the presence of microsporidian DNA in the 8 samples (prevalence of 0.51%). Six samples (Brazilian larvae) were related to Polydispyrenia simulii and Caudospora palustris reference sequences but in separate clusters. One sample was clustered with Amblyospora spp. Edhazardia aedis was the positive control taxon. Conclusions: Samples identified as Polydispyrenia spp. and Amblyospora spp. were grouped with P. simulii and Amblyospora spp., respectively, corroborating previous results. However, the 16S gene tree showed a considerable distance between the black fl y-infecting Amblyospora spp. and the mosquito-infecting spp. This distance suggests that these two groups are not congeneric. Additional genomic region evaluation is necessary to obtain a coherent phylogeny for this group. © 2014, Sociedade Brasileira de Medicina Tropical. All Rights reserved.


Gonzalez C.R.,Metropolitan University of Educational Sciences | Reyes C.,Laboratorio Of Entomologia Medica
Medical and Veterinary Entomology | Year: 2015

Four species of triatomines are known from Chile: Triatoma infestans Klug, Mepraia spinolai Porter, M. gajardoi Frías, Henry & González, and M. parapatrica Frías (Hemiptera: Reduviidae), the last three are endemic. The geographical distribution of M. gajardoi includes the coastal areas in the north of Chile between 18° and 21°S, an area with both a resident workforce and summer-season visitors. A study was developed to assess the risk of vectorial transmission of Chagas disease by M. gajardoi in hut settlements on the coast of the Tarapacá Region, in particular in Caleta San Marcos and Caleta Río Seco. The study comprised fingerstick sampling of 95 persons, venous samples from 29 domestic dogs and capture of 52 triatomines, from both fishing coves. The samples were analysed by enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) techniques. The results show that, of the total number of persons studied, 100% were negative for Trypanosoma cruzi Chagas (Trypanosomatida: Trypanosomatidae) antibodies, 10.34% of canids were positive for the antibody and 5.8% of M. gajardoi were infected to the PCR technique. The presence of this species in areas close to human settlements constitutes a risk to human populations established on the coast of northern Chile. © 2015 The Royal Entomological Society.


Dibo M.R.,Servico Regional 8 | Dibo M.R.,Laboratorio Of Vetores | de Menezes R.M.T.,Laboratorio Of Entomologia Medica | Ghirardelli C.P.,Laboratorio Of Entomologia Medica | And 2 more authors.
Revista da Sociedade Brasileira de Medicina Tropical | Year: 2011

Introduction: The objectives for this study were to measure the diversity of Culicidae species, describe their abundance and seasonal variation in São José do Rio Preto, SP, and discuss the risk of arbovirus infections. Methods: The collection of larval and adult mosquitoes was conducted monthly from 2006 to 2007 in an urban area and four sections of forested land. In the urban area, larvae were collected from sites where oviposition by Culex mosquitoes was most likely to occur. At two of the four sites in the forested land, adult mosquitoes were collected with the use of CDC traps at night, and a Nasci aspirator was used in the daytime at the two other collection sites. Results: In the urban area, 34 Culicidae species were identified out of a total sample of 8,683 specimens; of these specimens, 80.7% were Culex quinquefasciatus, 9.6% were Culex coronator, 3.2% were Aedes albopictus, and 1.1% were Ochlerotatus fluviatilis. The abundance of Cx. quinquefasciatus larvae was negatively related to rainfal. In the woods, 2,268 mosquitoes were collected, representing 10 genera and 46 species. The most abundant mosquito species were Aedeomyia squamipennis, Culex coronator, Culex (Mel.) Melanoconion section, Culex declarator, Ochlerotatus scapularis, Anopheles triannulatus, Culex bidens/interfor and Culex habilitator/pseudojhantinosoma. Conclusions: The abundance of Cx. quinquefasciatus in the urban area and the presence of other Culicidae species in urban areas and forested land point to the possibility of the transmission of West Nile virus and other arbovirus infections in São José do Rio Preto and other cities. Thus, the enacting of measures aimed at the surveillance of these arbovirus infections is essential.


Medeiros J.F.,Laboratorio Of Entomologia Medica | Costa C.A.,National Institute of Amazonian Research | de Lima A.M.,National Institute of Amazonian Research | Pessoa F.A.C.,Instituto Leonidas e Maria Deane
Revista da Sociedade Brasileira de Medicina Tropical | Year: 2014

Introduction: This study assessed the prevalence of Mansonella ozzardi in riverine communities of the Tefé River, Amazonas, Brazil. Methods: The prevalence of M. ozzardi was estimated by microscopic examination of thick blood smears. Results: The M. ozzardi prevalence rate was 6.3% (19/300). Filarial infection was found in 8 of the 11 communities surveyed, with prevalence rates varying from 2.5% to 22.2%. Conclusions: Tefé is a region of oil and natural gas exploration, in which there is a high turnover of workers. Migration patterns may facilitate the dissemination of mansonelliasis to other regions.


PubMed | National Institute of Amazonian Research, Instituto Leonidas e Maria Deane and Laboratorio Of Entomologia Medica
Type: Journal Article | Journal: Revista da Sociedade Brasileira de Medicina Tropical | Year: 2014

This study assessed the prevalence of Mansonella ozzardi in riverine communities of the Tef River, Amazonas, Brazil.The prevalence of M. ozzardi was estimated by microscopic examination of thick blood smears.The M. ozzardi prevalence rate was 6.3% (19/300). Filarial infection was found in 8 of the 11 communities surveyed, with prevalence rates varying from 2.5% to 22.2%.Tef is a region of oil and natural gas exploration, in which there is a high turnover of workers. Migration patterns may facilitate the dissemination of mansonelliasis to other regions.


Anopheles (Kerteszia) cruzii has been implicated as the primary vector of human and simian malarias out of the Brazilian Amazon and specifically in the Atlantic Forest regions. The presence of asymptomatic human cases, parasite-positive wild monkeys and the similarity between the parasites infecting them support the discussion whether these infections can be considered as a zoonosis. Although many aspects of the biology of An. cruzii have already been addressed, studies conducted during outbreaks of malaria transmission, aiming at the analysis of blood feeding and infectivity, are missing in the Atlantic Forest. This study was conducted in the location of Palestina, Juquitiba, where annually the majority of autochthonous human cases are notified in the Atlantic Forest of the state of São Paulo. Peridomiciliary sites were selected for collection of mosquitoes in a perimeter of up to 100 m around the residences of human malaria cases. The mosquitoes were analyzed with the purpose of molecular identification of blood-meal sources and to examine the prevalence of Plasmodium. A total of 13,441 females of An. (Ker.) cruzii were collected. The minimum infection rate was calculated at 0.03% and 0.01%, respectively, for P. vivax and P. malariae and only human blood was detected in the blood-fed mosquitoes analyzed. This data reinforce the hypothesis that asymptomatic human carriers are the main source of anopheline infection in the peridomiciliary area, making the probability of zoonotic transmission less likely to happen. © 2014 Rev. Inst. Med. Trop. Sao Paulo. All rights reserved.


Obara M.T.,Laboratorio Of Entomologia Medica | Otrera V.C.G.,Laboratorio Do Nucleo Of Pesquisa | Goncalves R.G.,University of Brasilia | dos Santos J.P.,Nucleo de Geoprocessamento | And 4 more authors.
Revista da Sociedade Brasileira de Medicina Tropical | Year: 2011

Introduction: Triatoma sordida Stål, 1859 populations were investigated for susceptibility to deltamethrin. Methods: This study aimed to analyze the resistance of 11 populations of insects from the States of Goiás, Mato Grosso and Mato Grosso do Sul by topical application bioassays. Results: The estimated LD50 and RR50 showed high levels of susceptibility (LD50 < 1 and RR50 < 2). However, analysis of the slope of the dose response curve showed that the populations of insects in the towns of Firminópolis/GO, Posse/GO, Poxoréu/MT, Douradina/MS and Aparecida do Taboado/MS present great probability of evolving resistance and, thus, are more likely to tolerate treatment with deltamethrin. Conclusions: Small changes in susceptibility and low levels of resistance were detected, but the temporal changes of susceptibility should be continuously monitored to adequately guide the actions of vector-control of DC.


Gimenez G.S.,Federal University of Rondônia | Coutinho-Neto A.,Federal University of Rondônia | Kayano A.M.,Federal University of Rondônia | Simoes-Silva R.,Federal University of Rondônia | And 9 more authors.
BioMed Research International | Year: 2014

Toxins purified from the venom of spiders have high potential to be studied pharmacologically and biochemically. These biomolecules may have biotechnological and therapeutic applications. This study aimed to evaluate the protein content of Parawixia bistriata venom and functionally characterize its proteins that have potential for biotechnological applications. The crude venom showed no phospholipase, hemorrhagic, or anti-Leishmania activities attesting to low genotoxicity and discrete antifungal activity for C. albicans. However the following activities were observed: anticoagulation, edema, myotoxicity and proteolysis on casein, azo-collagen, and fibrinogen. The chromatographic and electrophoretic profiles of the proteins revealed a predominance of acidic, neutral, and polar proteins, highlighting the presence of proteins with high molecular masses. Five fractions were collected using cation exchange chromatography, with the P4 fraction standing out as that of the highest purity. All fractions showed proteolytic activity. The crude venom and fractions P1, P2, and P3 showed larvicidal effects on A. aegypti. Fraction P4 showed the presence of a possible metalloprotease (60 kDa) that has high proteolytic activity on azo-collagen and was inhibited by EDTA. The results presented in this study demonstrate the presence of proteins in the venom of P. bistriata with potential for biotechnological applications. © 2014 Gizeli S. Gimenez et al.


PubMed | Laboratorio Of Entomologia Medica
Type: Journal Article | Journal: Revista da Sociedade Brasileira de Medicina Tropical | Year: 2011

Triatoma sordida Stl, 1859 populations were investigated for susceptibility to deltamethrin.This study aimed to analyze the resistance of 11 populations of insects from the States of Gois, Mato Grosso and Mato Grosso do Sul by topical application bioassays.The estimated LD50 and RR50 showed high levels of susceptibility (LD50 < 1 and RR50 < 2). However, analysis of the slope of the dose response curve showed that the populations of insects in the towns of Firminpolis/GO, Posse/GO, Poxoru/MT, Douradina/MS and Aparecida do Taboado/MS present great probability of evolving resistance and, thus, are more likely to tolerate treatment with deltamethrin.Small changes in susceptibility and low levels of resistance were detected, but the temporal changes of susceptibility should be continuously monitored to adequately guide the actions of vector-control of DC.

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