Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Parasitol Int ; 83: 102360, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33882331

RESUMO

Coelozoic parasites of the family Myxidiidae were observed in fish of the order Characiformes captured in the middle Tocantins River, Maranhão, Brazil, within the transition between the Cerrado savanna biome and the eastern extreme of the Brazilian Amazon Forest. The analysis of the morphological characteristics of the parasites, complemented with a Bayesian phylogenetic analysis, supported the description of new specie Myxidium imperatrizensis n. sp., found parasitising the gallbladder of specimens of the fish Triportheus angulatus. The study is also only the second report of the occurrence of Myxidium parasites in fish of the family Triportheidae in Brazilian rivers. The results of the present study expand the known distribution of the genera Myxidium the basin of the Tocantins River, the largest hydrographic basin located entirely within Brazil, which encompasses parts of both the Cerrado and Amazon biomes.


Assuntos
Caraciformes , Doenças dos Peixes/epidemiologia , Myxozoa/classificação , Doenças Parasitárias em Animais/epidemiologia , Animais , Brasil/epidemiologia , DNA Ribossômico/análise , Doenças dos Peixes/parasitologia , Microscopia Eletrônica de Varredura/veterinária , Myxozoa/anatomia & histologia , Myxozoa/genética , Myxozoa/ultraestrutura , Doenças Parasitárias em Animais/parasitologia , Prevalência , Rios/parasitologia
2.
Parasitol Res ; 119(12): 3987-3993, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32951144

RESUMO

Myxozoans of the family Myxobolidae are common parasites in fish. The diversity and ecology of the species of the genus Unicauda are poorly known, which hampers the understanding of the distribution and prevalence of this group of parasites. In the present study, cysts containing parasites whose morphology was consistent with the genus Unicauda were found in the circumorbital region of the ocular conjunctiva of the freshwater fish Moenkhausia grandisquamis Müller & Troschel, 1845 (Characiformes: Characidae) and Triportheus angulatus Spix & Agassiz, 1829 (Characiformes: Triportheidae). The spores have an oval body and long caudal appendage, with a mean total length of 65.2 ± 5.9 µm and width of 5.2 ± 0.7 µm, with two oval and symmetrical polar capsules of 4.9 ± 0.5 µm in length and 1.4 ± 0.2 µm in width, containing polar filaments with five or six coils. An integrated comparative analysis of the morphological characteristics of this parasite and partial sequences of the SSU rDNA gene supported the identification of a new species of histozoic parasite of the genus Unicauda found in fish from the Tocantins River basin, in the eastern Brazilian Amazon region. The new species was denominated by Unicauda tavaresii n. sp.


Assuntos
Characidae/parasitologia , Túnica Conjuntiva/parasitologia , Doenças dos Peixes/parasitologia , Myxozoa/classificação , Doenças Parasitárias em Animais/parasitologia , Animais , Brasil/epidemiologia , Filogenia , Rios/parasitologia , Esporos/ultraestrutura
3.
Rev Bras Parasitol Vet ; 28(3): 416-424, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365719

RESUMO

The aim of this was describe an infection by Kudoa orbicularis in freshwater catfish Trachelyopterus galeatus. A sample of 80 specimens of T. galeatus was collected in the municipality of Cachoeira do Arari, Marajó Island, in the state of Pará, Brazil. Pseudocysts were found in the muscle fibers of the epaxial and hypaxial regions of 85.0% of the specimens analyzed, reflecting a high infection rate. The pseudocysts contained spores that were pseudo-square in shape, with a mean length of 4.65 µm (range: 4.04-5.54) and mean width of 1.53 µm (1.56-1.74). Analyses on the morphology of the spores and a partial 934-bp sequence of the SSU rDNA gene confirmed that the microparasite was Kudoa orbicularis. This is the second record of this microparasite in a siluriform host in the Brazilian Amazon region.


Assuntos
Peixes-Gato/parasitologia , Doenças dos Peixes/parasitologia , Myxozoa/isolamento & purificação , Animais , Brasil , DNA Ribossômico/genética , Doenças dos Peixes/diagnóstico , Água Doce , Myxozoa/citologia , Myxozoa/genética , Filogenia , Reação em Cadeia da Polimerase
4.
Rev. bras. parasitol. vet ; 28(3): 416-424, July-Sept. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1042514

RESUMO

Abstract The aim of this was describe an infection by Kudoa orbicularis in freshwater catfish Trachelyopterus galeatus. A sample of 80 specimens of T. galeatus was collected in the municipality of Cachoeira do Arari, Marajó Island, in the state of Pará, Brazil. Pseudocysts were found in the muscle fibers of the epaxial and hypaxial regions of 85.0% of the specimens analyzed, reflecting a high infection rate. The pseudocysts contained spores that were pseudo-square in shape, with a mean length of 4.65 µm (range: 4.04-5.54) and mean width of 1.53 µm (1.56-1.74). Analyses on the morphology of the spores and a partial 934-bp sequence of the SSU rDNA gene confirmed that the microparasite was Kudoa orbicularis. This is the second record of this microparasite in a siluriform host in the Brazilian Amazon region.


Resumo O objetivo deste estudo foi descrever a infecção por Kudoa orbicularis em Trachelyopterus galeatus. Foram analisados 80 espécimes de T. galeatus capturados no município de Cachoeira do Arari, ilha de Marajó, estado do Pará, Brasil. A presença de pseudocistos nas fibras musculares das regiões epiaxial e hipoaxial em 85,0% dos exemplares analisados, mostra alto grau de infecção. Os pseudocistos continham esporos de formato pseudoquadrado, medindo 4,65 (4,04-5,54) µm de comprimento e 5,25 (4,78-5,98) µm de largura, com quatro cápsulas polares de tamanho iguais medindo 2,22 (2,05-2,32) µm de comprimento e 1,53 (1,56-1,74) µm de largura. Através das análises morfológicas dos esporos e molecular de uma sequência parcial de 934bps do gene SSU rDNA, confirma que o microparasito é Kudoa orbicularis, sendo este o segundo registro desse microparasito em hospedeiro da ordem Siluriformes da Amazônia brasileira.


Assuntos
Animais , Peixes-Gato/parasitologia , Myxozoa/isolamento & purificação , Doenças dos Peixes/parasitologia , Filogenia , Brasil , DNA Ribossômico/genética , Reação em Cadeia da Polimerase , Myxozoa/citologia , Myxozoa/genética , Doenças dos Peixes/diagnóstico , Água Doce
5.
Genome Biol Evol ; 10(9): 2366-2379, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29982381

RESUMO

The Pirarucu (Arapaima gigas) is one of the world's largest freshwater fishes and member of the superorder Osteoglossomorpha (bonytongues), one of the oldest lineages of ray-finned fishes. This species is an obligate air-breather found in the basin of the Amazon River with an attractive potential for aquaculture. Its phylogenetic position among bony fishes makes the Pirarucu a relevant subject for evolutionary studies of early teleost diversification. Here, we present, for the first time, a draft genome version of the A. gigas genome, providing useful information for further functional and evolutionary studies. The A. gigas genome was assembled with 103-Gb raw reads sequenced in an Illumina platform. The final draft genome assembly was ∼661 Mb, with a contig N50 equal to 51.23 kb and scaffold N50 of 668 kb. Repeat sequences accounted for 21.69% of the whole genome, and a total of 24,655 protein-coding genes were predicted from the genome assembly, with an average of nine exons per gene. Phylogenomic analysis based on 24 fish species supported the postulation that Osteoglossomorpha and Elopomorpha (eels, tarpons, and bonefishes) are sister groups, both forming a sister lineage with respect to Clupeocephala (remaining teleosts). Divergence time estimations suggested that Osteoglossomorpha and Elopomorpha lineages emerged independently in a period of ∼30 Myr in the Jurassic. The draft genome of A. gigas provides a valuable genetic resource for further investigations of evolutionary studies and may also offer a valuable data for economic applications.


Assuntos
Peixes/genética , Animais , Evolução Biológica , Evolução Molecular , Feminino , Genoma , Tamanho do Genoma , Masculino , Anotação de Sequência Molecular , Família Multigênica , Filogenia , Sequências Repetitivas de Ácido Nucleico , Sequenciamento Completo do Genoma
6.
Bioinformation ; 10(5): 246-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24966529

RESUMO

In this paper, an unsupervised artificial neural network was implemented to identify the patters of specific signatures. The network was based on the differential expression of miRNAs (under or over expression) found in healthy or cancerous gastric tissues. Among the tissues analyzes, the neural network evaluated 514 miRNAs of gastric tissue that exhibited significant differential expression. The result suggested a specific expression signature nine miRNAs (hsa-mir-21, hsa-mir-29a, hsa-mir-29c, hsa-mir-148a, hsa-mir-141, hsa-let-7b, hsa-mir-31, hsa-mir-451, and hsa-mir-192), all with significant values (p-value < 0.01 and fold change > 5) that clustered the samples into two groups: healthy tissue and gastric cancer tissue. The results obtained "in silico" must be validated in a molecular biology laboratory; if confirmed, this method may be used in the future as a risk marker for gastric cancer development.

7.
Med Mycol ; 47(2): 119-23, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18651310

RESUMO

Lacazia loboi is the etiologic agent of Jorge Lobo's disease, a cutaneous and subcutaneous mycosis endemic to Latin America tropical regions and characterized by chronic nodular or keloidal lesions which develop after traumatic events. A new method for the extraction of L. loboi yeast cells from biopsies of lobomycosis skin lesions is presented. The method is based on the proteolytic action of the enzyme dispase which is known for its action against fibronectin and collagen type IV. Fungal identification was based on histological examination of the biological material and molecular analysis based on 18S ribosomal sequences. Observations under optic and fluorescence microscopy proved the efficacy of enzymatic isolation of the lobomycosis etiologic agent, as well as identifying the organism's main parasitic characteristics. Molecular phylogenetic analysis corroborated the histological examination and indicated L. loboi relationship with other members of the Onygenales. Use of dispase proved to be ideal for the isolation of L. loboi from human biopsies, shows promise as an important tool for improving biological studies of this peculiar fungus.


Assuntos
Dermatomicoses/microbiologia , Endopeptidases/metabolismo , Onygenales/isolamento & purificação , Pele/metabolismo , Pele/microbiologia , Biópsia , Dermatomicoses/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Micologia/métodos , Onygenales/classificação , Onygenales/genética , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Pele/patologia
8.
Genet. mol. biol ; 29(1): 38-40, 2006. tab
Artigo em Inglês | LILACS | ID: lil-423417

RESUMO

Different risk factors for venous thromboembolism (VTE) have been identified, including hereditary abnormalities in the mechanisms of coagulation and fibrinolysis. We investigated five genetic polymorphisms (FVL G1691A, FII G20210A, MTHFR C677T, TAFI A152G and TAFI T1053C) associated with VTE in individuals from the city of Belém in the Brazilian Amazon who had no history of VTE. No significant difference was found between the observed and expected genotype frequencies for the loci analyzed. We found high frequencies of MTHFR C677T (33.9 percent) and TAFI T1053C (74 percent) and low frequencies of FVL (1.6 percent), FII G20210A (0.8 percent) and TAFI A152G (0.8 percent). The FVL G1691A, FII G20210A and MTHFR C677T frequencies were similar to those for European populations and populations of European descent living in the city of Ribeirão Preto in the Brazilian state of São Paulo. The frequency of the two TAFI mutations in the Belém individuals was not significantly different from that described for individuals from Ribeirão Preto. We suggest that the risks for VTE in the population of Belém are of the same magnitude as that observed in European populations and in populations with an expressive European contribution.


Assuntos
Humanos , Adolescente , Adulto , Fator V/genética , Protrombina , Trombofilia/epidemiologia , Brasil , Reação em Cadeia da Polimerase , Prevalência , Fatores de Risco , Trombofilia/genética
9.
Hum Biol ; 76(4): 643-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15754978

RESUMO

The frequency distribution of the CCR5-delta32, CCR2-64I, and SDF1-3'A alleles was studied in the urban population of Belém and in Afro-Brazilians, Amerindians, and Japanese immigrants in the state of Pará, Brazil. The results suggest that Amerindians may be genetically more susceptible to HIV-1 infection and disease progression than the other human groups studied.


Assuntos
Frequência do Gene , Predisposição Genética para Doença/etnologia , Genética Populacional , Polimorfismo de Fragmento de Restrição , Receptores CCR5/genética , Povo Asiático/genética , População Negra/genética , Brasil , Quimiocinas/genética , Progressão da Doença , Genótipo , HIV-1/genética , Humanos , Indígenas Sul-Americanos/genética , Japão/etnologia , Mutação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...