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1.
An Acad Bras Cienc ; 96(3): e20230629, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38922254

RESUMO

The current study proposes to investigate the diversity and phylogeny of trypanosomes parasitizing wild birds from the Brazilian Atlantic Forest. Cytological examination was carried out by light microscopy of blood smears and positive birds were selected for amplification of the 18S rDNA sequence through PCR. The resulting amplicons were subjected to purification, cloning, and sequencing analysis. Phylogenetic reconstruction was conducted, including all avian trypanosomes representative's lineages. A total of ten bird samples from species of Turdus flavipes (N=1/12), T. albicollis (N=1/8), Tachyphonus coronatus (N=6/121), Thamnophilus caerulescens (N=1/22) and Synallaxis spixi (N=1/8) were positive for Trypanosoma spp. In the six specimens of T. coronatus, five distinct lineages of Trypanosoma spp. 18S-rRNA were observed in ninety sequences obtained, and using the strategy of cloning independent PCR, it was possible to observe that two of them were related to T. avium (JB01/JB02), and three were closed related to T. bennetti (JB03/ JB04/JB05). Addionaly, all fifteen sequences obtained from T. caerulescens/ S. spixi/T. flavipes/T. albicollis were identical. The present research is the first study to access molecular diversity and polyparasitism by avian trypanosomes in Brazil. The current research exhibits the wide genetic variability in avian trypanosomes and its non-specific relationship with its avian hosts.


Assuntos
Aves , Filogenia , Reação em Cadeia da Polimerase , Trypanosoma , Animais , Brasil , Trypanosoma/classificação , Trypanosoma/genética , Trypanosoma/isolamento & purificação , Aves/parasitologia , Floresta Úmida , RNA Ribossômico 18S/genética , DNA de Protozoário/genética , Tripanossomíase/veterinária , Tripanossomíase/parasitologia , Doenças das Aves/parasitologia , Variação Genética , DNA Ribossômico/genética , Análise de Sequência de DNA
2.
An Acad Bras Cienc ; 96(1): e20230739, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511746

RESUMO

High infestations of epibiont ciliates on vertebrates or invertebrates are normally related to aquaculture tanks or similar environments, and the importance of this relationship in natural habitats is often disregarded. Here, we describe the first record of high infestation of ciliates on Aegla serrana in South America and conduct a brief morphological and phylogenetic characterization of these ciliates. Our findings confirm that cases of high infestation of ciliates on metazoans can indeed occur in natural environments.


Assuntos
Anomuros , Cilióforos , Animais , Brasil , Filogenia , Cilióforos/genética , Ecossistema
3.
J Eukaryot Microbiol ; 69(4): e12915, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35403310

RESUMO

The family Ophryoscolecidae currently comprises 225 species of trichostomatid ciliates, subdivided into three subfamilies (Entodiniinae, Diplodiniinae, and Ophryoscolecinae). The last taxonomic review of the family was performed 55 years ago, but recent morphological and molecular studies indicate the need for a profound review of the systematics of this taxon, since its current taxonomy is insufficient to organize the diversity of the group. Here, we briefly review the systematics of the family Ophryoscolecidae based on information recovered from the literature and new morphological and molecular data. We add four new 18S rDNA sequences of ophryoscolecids to molecular databases, which contributed to improving the comprehension of intrafamily relationships within this group. Finally, we discuss some systematic problems and suggest approaches to resolve such inconsistencies in the future.


Assuntos
Cilióforos , Cilióforos/genética , DNA Ribossômico/genética , Filogenia
4.
Curr Microbiol ; 78(11): 3872-3876, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34510223

RESUMO

The family Cycloposthiidae (Entodiniomorphida) comprises ciliated protists that are symbionts of the gastrointestinal tract of several herbivore mammals, such as rodents, elephants, equids, primates, hippopotamus, marsupials, rhinoceros and tapir, where they contribute to the digestion of their host's plant-based diet. Despite the significance of these ciliates to the evolution of their hosts, many characters used in the taxonomy of the group are homoplastic and most of the valid species do not have molecular data available. For these reasons the systematics of this family is poorly understood. Here, we sequenced the 18S-rDNA of ten cycloposthiids, including nine Cycloposthium spp. and Monoposthium cynodontum, all of them isolated from the cecum of a Brazilian capybara. Our phylogenetic analyses indicate that the family Cycloposthiidae might be polyphyletic, while M. cynodontum and Cycloposthium spp. constitute a single monophyletic group. Given the great morphological and molecular similarities between members of M. cynodontum and Cycloposthium ciliates, it is possible that this species, although it has been described in the genus Monoposthium, is actually a Cycloposthium ciliate.


Assuntos
Cilióforos , Roedores , Animais , Cilióforos/genética , DNA Ribossômico/genética , Trato Gastrointestinal , Filogenia
5.
Parasitol Res ; 120(9): 3287-3296, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34374851

RESUMO

Literature data on toucans haemosporidians are scarce and all reports come from investigations in Brazil. Muniz et al. (Rev Bras Malariol 3: 339-356, Muniz et al., Rev Bras Malariol 3:339-356, 1951) and Muniz and Soares (Rev Bras Malar 611-617, Muniz J, Soares R de RL (1954) Nota sôbre um parasita do gênero Plasmodium encontrado no Ramphastos toco Müller, 1776, "Tucano-Açu", e diferente do Plasmodium huffi: Plasmodium pinottii n. sp. Rev Bras Malar 611 - 617.) described two Plasmodium species, P. huffi and P. pinottii, in Ramphastos toco. Later, Manwell and Sessler (J Protozol 18: 570-574, Manwell and Sessler, Malaria Parasites of Toucans J Protozol 18:570-574, 1971) established a new subspecies, P. nucleophilum toucani. In the last review on avian haemosporidians, Valkiunas (Valkiunas, Avian malaria parasites and other haemosporidia, CRC Press, New York, 2005) highlighted that P. huffi was insufficiently characterized, considering it a lost lineage. Also, the original description of P. huffi was considered insufficiently clear, due to a possible co-infection of the toucan hosts with a Novyella-like species. Here, we redescribed the species Plasmodium (Huffia) huffi based on morphological and molecular data, which were found in two toucan species, Ramphastos toco and Pteroglossus aracari from Brazil. Morphological features of the specimens are markedly the same as the original description. In R. toco, we observe two individuals infected, one infected only with P. huffi and one co-infected with P. huffi and the Novyella-like species, as observed in the original description. Also, we observe one R. toco infected only with the Novyella-like species, identified by morphological and molecular data as Plasmodium (Novyella) nucleophilum nucleophilum. In this way, it was possible to redescribe Plasmodium huffi in detail, without the doubt characters observed in the original description. Moreover, by applying species delimitation algorithms to a large Plasmodium phylogeny, we were able to identify new possible hosts for P. huffi and extend its geographic distribution to include North America.


Assuntos
Aves/parasitologia , Malária Aviária , Plasmodium , Animais , Brasil , Malária Aviária/parasitologia , Filogenia , Plasmodium/genética , Plasmodium/isolamento & purificação
6.
Parasitol Int ; 84: 102375, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33957295

RESUMO

Parasites of the genus Haemoproteus have been reported in almost all avian clades and zoogeographic regions, except Antarctica. However, despite the large number of reports worldwide, they are poorly studied in the Neotropical region, which includes the Atlantic Forest, a biodiversity hotspot with more than 890 bird species, of which 24% are endemic. Haemoproteus (Haemoproteus) paramultipigmentatus was described by morphological and molecular analyses in 2013 infecting Columbiform birds in Mexico. However, since the original description this parasite has not been studied in detail. Here, we investigate the prevalence of Haemoproteus spp. in Brazilian Columbiformes and conducted a taxonomic integrative study of the species Haemoproteus (Haemoproteus) paramultipigmentatus, including new morphological and molecular data from a Brazilian population. Moreover, we provide discussions about the geographic distribution and phylogenetic relationships between different lineages of this parasite. Our findings demonstrated a high prevalence of Haemoproteus spp. infection in Brazilian Columbiformes, which is in accordance with previous studies. Morphological characterization of H. paramultipigmentatus revealed minor differences from the original description. Through molecular and phylogenetic analyses we identified a new lineage of H. paramultipigmentatus that was added to the genetic databases. Our findings also suggest a new geographical distribution for this hemoparasite, including South American countries, and raise discussions about its current distribution.


Assuntos
Doenças das Aves/epidemiologia , Columbidae , Haemosporida/classificação , Interações Hospedeiro-Parasita , Infecções Protozoárias em Animais/epidemiologia , Animais , Animais Selvagens , Doenças das Aves/parasitologia , Brasil , Citocromos b/análise , Haemosporida/genética , Haemosporida/isolamento & purificação , Prevalência , Infecções Protozoárias em Animais/parasitologia , Proteínas de Protozoários/análise
7.
Environ Pollut ; 268(Pt A): 115760, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33162216

RESUMO

The aim of our study was to evaluate the water quality of an urban stream in southeastern Brazil by analyzing epibenthic ciliates, and to investigate the existence of phylogenetic signal for saprobity in ciliates. However, before conducting this type of phylogenetic study, it is necessary to evaluate if the saprobic classification used frequently in the northern Hemisphere is suitable for neotropical ecosystems. Sediment samples were collected from five sampling stations: two in rural areas and three in urban areas. During the one-year study, with monthly collections, 39 ciliates species were found, of which 32 are included in the saprobic system. Physical, chemical and biological parameters of water confirm the spatial heterogeneity of the sampling stations, with a clear influence of organic pollution on the composition and structure of ciliates taxocenosis. The saprobic index and the saprobic valence index were used to evaluate the water quality of the sampling stations and demonstrated clear heterogeneity between the stations and high degree of pollution of the urban area. These sampling stations were dominated by ciliates indicators of polysaprobric environments. Since we were able to successfully use the saprobic index in a limnic ecosystem in Brazil, we applied the phylogenetic signal validation as a tool for saprobity prediction of the limnic ciliate species not yet analyzed. A phylogenetic tree containing only 18S-rDNA nominal sequences of freshwater ciliates was estimated and used to explore the existence of the phylogenetic signal, which showed that the sensitivity/tolerance of ciliates to organic pollution reflected evolutionary divergence. The results confirm the existence of phylogenetic signal for the saprobrity in Ciliophora. Also, our results suggest that evolutionary analysis is a potential method to predict lineages of ciliates not yet classified for saprobity.


Assuntos
Cilióforos , Qualidade da Água , Brasil , Cilióforos/genética , DNA Ribossômico , Ecossistema , Biomarcadores Ambientais , Filogenia
8.
Parasitol Res ; 120(1): 243-255, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33169308

RESUMO

Haemoproteus syrnii is a haemosporidian parasite found in owls. Although morphological and molecular data on the species is available, its exo-erythrocytic development was never researched. In this study, we provide the morphological, morphometric, and molecular characterization of H. syrnii populations found in owl species from Minas Gerais, southeast Brazil. We also characterized the coalescent species delimitation based on the molecular and histopathology data. Samples from 54 owls from six different species were analyzed, generating 11 sequences of the cyt b gene, from which six were new sequences. The overall prevalence of infection was high (72.22%). The H. syrnii sequences were grouped into two well-supported independent clades, which included other Haemoproteus (Parahaemoproteus) species. This was supported by both the coalescent species delimitation analysis and by the genetic divergence between lineages of these distinct clades. There were small morphological and morphometric differences within the population presented in this study. However, when compared with other studies, the molecular analysis demonstrated considerable intraspecific variation and suggests potential cryptic species. The histopathological analysis revealed, for the first time, that lungs and skeletal muscle are exo-erythrocytic stage location of H. syrnii, and that the parasite is linked to the histopathological changes found in owls. This study brings new data from Haemoproteus species biology and host infection, and improves host-parasite relationship understanding under an owl conservation perspective.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/genética , Infecções Protozoárias em Animais/parasitologia , Estrigiformes/parasitologia , Animais , Brasil , Citocromos b/genética , Eritrócitos/parasitologia , Haemosporida/classificação , Haemosporida/isolamento & purificação , Interações Hospedeiro-Parasita , Filogenia
9.
Parasitol Res ; 119(12): 4033-4047, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33030600

RESUMO

Haemoproteus spp. and Plasmodium spp. are blood parasites that occur in birds worldwide. Identifying the species within this group is complex, especially in wild birds that present low parasitemia when captured, making morphological identification very difficult. Thus, the use of alternative tools to identify species may be useful in the elucidation of the distribution of parasites that circulate in bird populations. The objectives of this study were to determine the prevalence and parasitemia of the genera Plasmodium and Haemoproteus in Tachyphonus coronatus in the Atlantic Forest, Brazil, and to evaluate the molecular diversity, geographic distribution, and specificity of these parasites based on coalescent species delimitation methods. Microscopic analysis, PCR, cyt b gene sequencing, phylogenetic analysis and coalescent species delimitation using single-locus algorithms were performed (Poisson tree process (PTP) and multi-rate Poisson tree process (MPTP) methods). The analyses were performed in 117 avian host individuals. The prevalence was 55.5% for Plasmodium and 1.7% for Haemoproteus, with a mean parasitemia of 0.06%. Twenty-five Plasmodium and two Haemoproteus lineages were recovered. The MPTP method recovered seven different evolutionarily significant units (ESUs) of Plasmodium and one of Haemoproteus, whereas PTP presented fourteen ESUs of Plasmodium and one of Haemoproteus. The MPTP was more consistent with current taxonomy, while PTP overestimated the number of lineages. These ESUs are widely distributed and have already been found in 22 orders of birds that, all together, inhabit every continent, except Antarctica. The computational methods of species delimitation proved to be effective in cases where the classification of Haemosporida based just on morphology is insufficient.


Assuntos
Doenças das Aves/parasitologia , Aves/parasitologia , Haemosporida/classificação , Parasitemia/epidemiologia , Parasitemia/veterinária , Animais , Animais Selvagens/genética , Brasil/epidemiologia , Citocromos b/genética , Haemosporida/genética , Haemosporida/isolamento & purificação , Filogenia , Plasmodium/genética , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/parasitologia
10.
Rev Bras Parasitol Vet ; 29(4): e011520, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33053056

RESUMO

Haemoproteus spp. are protozoan parasites found in birds around the world. These parasites are identified through the morphology of gametocytes, phylogenetic analysis based on the mitochondrial cytb gene, and the parasite's geographic distribution. The absence of erythrocytic merogony, high intraspecific genetic variation and low parasitemia in wild birds makes it essential to use integrative approaches that assist in the identification of these parasites. Thus, microscopic and molecular analyses, combined with spatial distribution, were carried out to verify the presence of Haemoproteus spp. in wild birds in Brazil. Light microscopy revealed one Tangara sayaca bird was parasitized by Haemoproteus coatneyi and, two specimens of Zonotrichia capensis presented Haemoproteus erythrogravidus. The morphology of the gametocytes of these two parasitic species showed high similarity. The molecular analysis revealed the presence of one lineage of H. coatneyi and two lineages of H. erythrogravidus, one of which is considered a new lineage. These lineages were grouped phylogenetically in separate clades, with low genetic divergence, and the H. erythrogravidus lineage emerged as an internal group of the lineages of H. coatneyi. The geographic distribution demonstrated that the two species occur in the American continent. This is the first report of H. erythrogravidus in Brazil.


Assuntos
Doenças das Aves , Haemosporida , Passeriformes/parasitologia , Infecções Protozoárias em Animais , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Brasil , Citocromos b/genética , Florestas , Haemosporida/classificação , Haemosporida/genética , Filogenia , Infecções Protozoárias em Animais/epidemiologia
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