RESUMO
Epithelial gill cell morphology and distribution were investigated in the armored catfish, Hypostomus cf. plecostomus, which lives in soft ion-poor Brazilian freshwaters. Pavement cells are the most abundant type of cell on both filament and lamellar epithelia and there are a great number of mucous and chloride cells between them. Mucous cells are almost covered by adjacent pavement cells and have large packed granules showing electrondense differences. No mucous cells were found on the lamellar epithelium. Chloride cell were distributed throughout both epithelia and usually have large apical surface facing the external medium and may exhibit short and sparsely distributed microvilli. The presence of chloride cells on the lamellar epithelium may be an adaptation to low ion concentrations in the water, allowing for improved ion-transport capacity of the gill. The large size of these cells increases the water-blood barrier and may affect the transference of respiratory gases. However, the negative effect on the respiratory process may be minimized by this species' ability to resort to atmospheric air to fulfill its oxygen requirements.
Assuntos
Peixes-Gato/anatomia & histologia , Células Epiteliais , Brânquias/citologia , Animais , FotomicrografiaRESUMO
PURPOSE: To report the outcome of microsporidial keratoconjunctivitis in a patient with acquired immunodeficiency syndrome (AIDS) after highly active antiretroviral therapy without any specific treatment for microsporidiosis. METHODS: Case report. A 42-year-old woman diagnosed with AIDS and severe immunodepression (CD4+ of 9 cells/mm(3) and viral load of 460,000/mm(3)), antiretroviral naive, presented with cerebral toxoplasmosis and microsporidial keratoconjunctivitis in the right eye documented by conjunctival scraping and electron microscopy. RESULTS: The patient was treated with a combination of indinavir, stavudine, and lamivudine, besides sulfadiazine and pyrimethamine. No specific treatment for the microsporidial keratoconjunctivitis was attempted. One month later, the keratoconjunctivitis had disappeared. CONCLUSION: This case suggests that microsporidial keratoconjunctivitis in the setting of AIDS and severe immunodepression can be effectively managed with highly active antiretroviral therapy alone.
Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções Oculares Parasitárias/tratamento farmacológico , Ceratoconjuntivite/tratamento farmacológico , Microsporídios/isolamento & purificação , Microsporidiose/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/parasitologia , Adulto , Animais , Quimioterapia Combinada , Infecções Oculares Parasitárias/parasitologia , Feminino , Humanos , Indinavir/uso terapêutico , Ceratoconjuntivite/parasitologia , Lamivudina/uso terapêutico , Microsporidiose/parasitologia , Estavudina/uso terapêutico , Acuidade VisualRESUMO
Epithelial gill cell morphology and distribution were investigated in the armored catfish, Hypostomus cf. plecostomus, which lives in soft ion-poor Brazilian freshwaters. Pavement cells are the most abundant type of cell on both filament and lamellar epithelia and there are a great number of mucous and chloride cells between them. Mucous cells are almost covered by adjacent pavement cells and have large packed granules showing electrondense differences. No mucous cells were found on the lamellar epithelium. Chloride cell were distributed throughout both epithelia and usually have large apical surface facing the external medium and may exhibit short and sparsely distributed microvilli. The presence of chloride cells on the lamellar epithelium may be an adaptation to low ion concentrations in the water, allowing for improved ion-transport capacity of the gill. The large size of these cells increases the water-blood barrier and may affect the transference of respiratory gases. However, the negative effect on the respiratory process may be minimized by this species' ability to resort to atmospheric air to fulfill its oxygen requirements