KARIN KIRCHGATTER
Projetos de Pesquisa
Unidades Organizacionais
LIM/49 - Laboratório de Protozoologia, Hospital das Clínicas, Faculdade de Medicina - Líder
6 resultados
Resultados de Busca
Agora exibindo 1 - 6 de 6
- Detection of Reticuloendotheliosis Virus in Muscovy Ducks, Wild Turkeys, and Chickens in Brazil(2020) CALEIRO, Giovana S.; NUNES, Cristina F.; URBANO, Paulo R.; KIRCHGATTER, Karin; ARAUJO, Jansen de; DURIGON, Edison Luiz; THOMAZELLI, Luciano M.; STEWART, Brittany M.; EDWARDS, Dustin C.; ROMANO, Camila M.Reticuloendotheliosis viruses (REVs) are known to cause immunosuppressive and oncogenic disease that affects numerous avian species. Reticuloendotheliosis viruses are present worldwide and recently have been reported in South America with cases of infected commercial flocks in Argentina. We surveyed for the presence of REV in birds from a state in the northern region of Brazil using real-time PCR. We report here the presence of REV in Brazil, detected in Muscovy Ducks (Cairina moschata), Wild Turkeys (Meleagris gallopavo), and chickens (Gallus gallus) at a relatively high prevalence (16.8%). Phylogenetic analysis indicated a close relationship of these strains to variants in the US. This study provides evidence of REV in the Amazon biome and provides a baseline for future surveillance of the virus in the region and throughout Brazil.
- Naturally Acquired Humoral Immunity against Malaria Parasites in Non-Human Primates from the Brazilian Amazon, Cerrado and Atlantic Forest(2020) MONTEIRO, Eliana Ferreira; FERNANDEZ-BECERRA, Carmen; ARAUJO, Maisa da Silva; MESSIAS, Mariluce Rezende; OZAKI, Luiz Shozo; DUARTE, Ana Maria Ribeiro de Castro; BUENO, Marina Galvao; CATAO-DIAS, Jose Luiz; CHAGAS, Carolina Romeiro Fernandes; MATHIAS, Bruno da Silva; SANTOS, Mayra Gomes dos; SANTOS, Stefanie Vanessa; HOLCMAN, Marcia Moreira; JR, Julio Cesar de Souza; KIRCHGATTER, KarinNon-human primates (NHPs) have been shown to be infected by parasites of the genusPlasmodium, the etiological agent of malaria in humans, creating potential risks of zoonotic transmission.Plasmodium brasilianum, a parasite species similar toP. malariaeof humans, have been described in NHPs from Central and South America, including Brazil. The merozoite surface protein 1 (MSP1), besides being a malaria vaccine candidate, is highly immunogenic. Due to such properties, we tested this protein for the diagnosis of parasite infection. We used recombinant proteins ofP. malariaeMSP1, as well as ofP. falciparumandP. vivax, for the detection of antibodies anti-MSP1 of these parasite species, in the sera of NHPs collected in different regions of Brazil. About 40% of the NHP sera were confirmed as reactive to the proteins of one or more parasite species. A relatively higher number of reactive sera was found in animals from the Atlantic Forest than those from the Amazon region, possibly reflecting the former more intense parasite circulation among NHPs due to their proximity to humans at a higher populational density. The presence ofPlasmodiumpositive NHPs in the surveyed areas, being therefore potential parasite reservoirs, needs to be considered in any malaria surveillance program.
- Evolutionary ecology, taxonomy, and systematics of avian malaria and related parasites(2020) FECCHIO, Alan; CHAGAS, Carolina R. F.; BELL, Jeffrey A.; KIRCHGATTER, KarinHaemosporidian parasites of the genera Plasmodium, Leucocytozoon, and Haemoproteus are one of the most prevalent and widely studied groups of parasites infecting birds. Plasmodium is the most well-known haemosporidian as the avian parasite Plasmodium relictum was the original transmission model for human malaria and was also responsible for catastrophic effects on native avifauna when introduced to Hawaii. The past two decades have seen a dramatic increase in research on avian haemosporidian parasites as a model system to understand evolutionary and ecological parasite-host relationships. Despite haemosporidians being one the best studied groups of avian parasites their specialization among avian hosts and variation in prevalence amongst regions and host taxa are not fully understood. In this review we focus on describing the current phylogenetic and morphological diversity of haemosporidian parasites, their specificity among avian and vector hosts, and identifying the determinants of haemosporidian prevalence among avian species. We also discuss how these parasites might spread across regions due to global climate change and the importance of avian migratory behavior in parasite dispersion and subsequent diversification.
- An inverse latitudinal gradient in infection probability and phylogenetic diversity for Leucocytozoon blood parasites in New World birds(2020) FECCHIO, Alan; BELL, Jeffrey A.; BOSHOLN, Mariane; VAUGHAN, Jefferson A.; TKACH, Vasyl V.; LUTZ, Holly L.; CUETO, Victor R.; GOROSITO, Cristian A.; GONZALEZ-ACUNA, Daniel; STROMLUND, Chad; KVASAGER, Danielle; COMICHE, Kiba J. M.; KIRCHGATTER, Karin; PINHO, Joao B.; BERV, Jacob; ANCIAES, Marina; FONTANA, Carla S.; ZYSKOWSKI, Kristof; SAMPAIO, Sidnei; DISPOTO, Janice H.; GALEN, Spencer C.; WECKSTEIN, Jason D.; CLARK, Nicholas J.Geographic variation in environmental conditions as well as host traits that promote parasite transmission may impact infection rates and community assembly of vector-transmitted parasites. Identifying the ecological, environmental and historical determinants of parasite distributions and diversity is therefore necessary to understand disease outbreaks under changing environments. Here, we identified the predictors and contributions of infection probability and phylogenetic diversity of Leucocytozoon (an avian blood parasite) at site and species levels across the New World. To explore spatial patterns in infection probability and lineage diversity for Leucocytozoon parasites, we surveyed 69 bird communities from Alaska to Patagonia. Using phylogenetic Bayesian hierarchical models and high-resolution satellite remote-sensing data, we determined the relative influence of climate, landscape, geography and host phylogeny on regional parasite community assembly. Infection rates and parasite diversity exhibited considerable variation across regions in the Americas. In opposition to the latitudinal gradient hypothesis, both the diversity and prevalence of Leucocytozoon parasites decreased towards the equator. Host relatedness and traits known to promote vector exposure neither predicted infection probability nor parasite diversity. Instead, the probability of a bird being infected with Leucocytozoon increased with increasing vegetation cover (NDVI) and moisture levels (NDWI), whereas the diversity of parasite lineages decreased with increasing NDVI. Infection rates and parasite diversity also tended to be higher in cooler regions and higher latitudes. Whereas temperature partially constrains Leucocytozoon diversity and infection rates, landscape features, such as vegetation cover and water body availability, play a significant role in modulating the probability of a bird being infected. This suggests that, for Leucocytozoon, the barriers to host shifting and parasite host range expansion are jointly determined by environmental filtering and landscape, but not by host phylogeny. Our results show that integrating host traits, host ancestry, bioclimatic data and microhabitat characteristics that are important for vector reproduction are imperative to understand and predict infection prevalence and diversity of vector-transmitted parasites. Unlike other vector-transmitted diseases, our results show that Leucocytozoon diversity and prevalence will likely decrease with warming temperatures.
- Phylogeny of Anopheles (Kerteszia) (Diptera: Culicidae) Using Mitochondrial Genes(2020) KIRCHGATTER, Karin; GUIMARAES, Lilian de Oliveira; TRUJILLANO, Henrry Hugo Yanez; ARIAS, Fernando Rafael; CACERES, Abraham German; DUARTE, Ana Maria Ribeiro de Castro; MALAFRONTE, Rosely dos Santos; TUBAKI, Rosa Maria; SALLUM, Maria Anice MurebIdentification of mosquito species is necessary for determining the entomological components of malaria transmission, but it can be difficult in morphologically similar species. DNA sequences are largely used as an additional tool for species recognition, including those that belong to species complexes. Kerteszia mosquitoes are vectors of human and simian malaria in the Neotropical Region, but there are few DNA sequences of Kerteszia species in public databases. In order to provide relevant information about diversity and improve knowledge in taxonomy of Kerteszia species in Peru, we sequenced part of the mitochondrial genome, including the cytochrome c oxidase I (COI) barcode region. Phylogenetic analyses structured all species of mosquitoes collected in Peru into a single clade, separate from the Brazilian species. The Peruvian clade was composed of two lineages, encompassing sequences from Anopheles (Kerteszia) boliviensis and Anopheles (Kerteszia) pholidotus. An. pholidotus sequences were recorded for the first time in Peru, whereas An. boliviensis sequences were for the first time published in the GenBank database. Sequences generated from specimens morphologically identified as Anopheles (Kerteszia) cruzii clustered into three separate clades according to the collection localities of Serra do Mar, Serra da Mantiqueira, and Serra da Cantareira, confirming An. cruzii as a species complex, composed of at least three putative species.
- Wing Geometric Morphometrics as a Tool for the Identification ofCulexSubgenus Mosquitoes ofCulex(Diptera: Culicidae)(2020) SIMOES, Roseli Franca; WILKE, Andre Barretto Bruno; CHAGAS, Carolina Romeiro Fernandes; MENEZES, Regiane Maria Tironi de; SUESDEK, Lincoln; MULTINI, Laura Cristina; SILVA, Fabiana Santos; GRECH, Marta Gladys; MARRELLI, Mauro Toledo; KIRCHGATTER, KarinSimple Summary Different mosquito species have different ecology and behaviors. Therefore, the correct identification of vector mosquito species is essential for the development of targeted mosquito control operations. Traditionally, the identification of mosquitoes to species relies on differences in their external morphological characters. Identifying mosquitoes can be challenging if the specimen is either damaged or if only a few morphological characters can be used to sort them apart. For this reason, this study focused on the use of wing geometric morphometrics to identifyCulexspecies from the subgenusCulexthat are not easily identified by their external morphology. We analyzed the wing shape variation of 11 different species. Our results indicated that the species in this study were identified with high degrees of confidence based on their wing shape variation. From all possible comparisons in the cross-validated reclassification test, 87 yielded values higher than 70%, with 13 comparisons yielding 100% reclassification scores. Overall, our results are suggesting that wing geometric morphometrics is a reliable tool to identifyCulexspecies of the subgenusCulex. Culexis the largest subgenus within the genusCulexthat includes important vectors of diseases. The correct identification of mosquitoes is critical for effective control strategies. Wing geometric morphometrics (WGM) has been used to identify mosquito species alongside traditional identification methods. Here, WGM was used for elevenCulexspecies from Sao Paulo, Brazil, and one from Esquel, Argentina. Adult mosquitoes were collected using CDC (Centers for Disease Control) traps, morphologically identified and analyzed by WGM. The canonical variate analysis (CVA) was performed and a Neighbor-joining (NJ) tree was constructed to illustrate the patterns of species segregation. A cross-validated reclassification test was also carried out. From 110 comparisons in the cross-validated reclassification test, 87 yielded values higher than 70%, with 13 comparisons yielding 100% reclassification scores.Culexquinquefasciatusyielded the highest reclassification scores among the analyzed species, corroborating with the results obtained by the CVA, in whichCx.quinquefasciatuswas the most distinct species. The high values obtained at the cross-validated reclassification test and in the NJ analysis as well as the segregation observed at the CVA made it possible to distinguish amongCulexspecies with high degrees of confidence, suggesting that WGM is a reliable tool to identifyCulexspecies of the subgenusCulex.