RESUMO
The main effector mechanisms of neutrophils are the release of neutrophil extracellular traps (NETs) and myeloperoxidase (MPO). In this work, we evaluated the role of NETs and the activity of MPO in the interactions of rodent neutrophils with amoebae and in amoebic liver abscess (ALA)-resistant and ALA-susceptible models. We showed with in vitro assays that mice produced greater amounts of NETs and MPO than did hamsters, and the elastase activity was high in both models. However, the inhibition of NETs and MPO promoted an increase in amoeba viability in the mice. The mouse ALAs showed a more profound presence of NETs and MPO than did the hamster ALAs. We concluded that both effector mechanisms were essential for the amoebic damage and could prevent the formation of ALAs in the resistant model.
Assuntos
Entamoeba histolytica/imunologia , Armadilhas Extracelulares/imunologia , Abscesso Hepático Amebiano/imunologia , Neutrófilos/imunologia , Peroxidase/metabolismo , Animais , Cricetinae , Suscetibilidade a Doenças , Humanos , Abscesso Hepático Amebiano/veterinária , Masculino , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Members of the genus Acanthamoeba are usually free-living amebae and are found in a variety of ecological niches including soil, fresh and brackish water, dust in air, filters of heating, ventilating, and air conditioning units, swimming pools and hot tubs, etc. Occasionally, they are also known to cause central nervous system infections in humans and other animals. We isolated into culture an amoeba from the liver tissue of a keel-billed toucan and identified it as Acanthamoeba sp. based on culture characteristics and immunofluorescent analysis. Further, we characterized the cultured amoeba and also the amoeba in the liver tissue as Acanthamoeba, genotype T4, by sequencing a diagnostic region of the nuclear small subunit ribosomal RNA gene.
Assuntos
Acanthamoeba/isolamento & purificação , Doenças das Aves/parasitologia , Abscesso Hepático Amebiano/veterinária , Acanthamoeba/classificação , Acanthamoeba/genética , Animais , Aves , DNA de Protozoário/genética , Técnica Indireta de Fluorescência para Anticorpo/métodos , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Genótipo , Humanos , Abscesso Hepático Amebiano/parasitologia , Filogenia , RNA Ribossômico/genéticaRESUMO
Three cases of hepatic amebiasis and one case of gastric amebiasis were diagnosed in black and white colobus monkeys during a 9-month period. The diagnosis was difficult because of the absence of trophozoites and cysts in the feces and because of few trophozoites found in many of the hepatic lesions. Indirect hemagglutination titers were diagnostic in 2 monkeys.
Assuntos
Amebíase/veterinária , Animais de Zoológico , Cercopithecidae , Colobus , Surtos de Doenças/veterinária , Entamebíase/veterinária , Abscesso Hepático Amebiano/veterinária , Doenças dos Macacos/epidemiologia , Úlcera Gástrica/veterinária , Animais , Animais de Zoológico/parasitologia , California , Cercopithecidae/parasitologia , Colobus/parasitologia , Entamoeba histolytica , Entamebíase/epidemiologia , Feminino , Abscesso Hepático Amebiano/epidemiologia , Masculino , Doenças dos Macacos/etiologia , Necrose , Úlcera Gástrica/epidemiologia , Úlcera Gástrica/etiologiaRESUMO
Of 500 red-footed tortoises imported to southern Florida, approximately 200 died during a 2-month period. Clinical signs were nonspecific and included anorexia, listlessness, and watery diarrhea, with lingering death. Necropsy consistently revealed thickened duodenum, with necrotic mucosa and multifocal to diffuse areas of hepatic necrosis. Histologic evaluation of tissues demonstrated numerous amebae in intestinal and hepatic lesions.
