RESUMO
AIMS: Cardiovascular manifestations are a major cause of mortality in Marfan syndrome (MFS). Animal models that mimic the syndrome and its clinical variability are instrumental for understanding the genesis and risk factors for cardiovascular disease in MFS. This study used morphological and ultrastructural analysis to the understanding of the development of cardiovascular phenotypes of the the mgΔloxPneo model for MFS. METHODS AND RESULTS: We studied 6-month-old female mice of the 129/Sv background, 6 wild type (WT) and 24 heterozygous animals from the mgΔloxPneo model. Descending thoracic aortic aneurysm and/or dissection (dTAAD) were identified in 75% of the MFS animals, defining two subgroups: MFS with (MFS+) and without (MFS-) dTAAD. Both subgroups showed increased fragmentation of elastic fibers, predominance of type I collagen surrounding the elastic fiber and fragmentation of interlaminar fibers when compared to WT. However, only MFS animals with spine tortuosity developed aortic aneurysm/dissection. The aorta of MFS+ animals were more tortuous compared to those of MFS- and WT mice, possibly causing perturbations of the luminal blood flow. This was evidenced by the detection of diminished aorta-blood flow in MFS+. Accordingly, only MFS+ animals presented a process of concentric cardiac hypertrophy and a significantly decreased ratio of left and right ventricle lumen area. CONCLUSIONS: We show that mgΔloxPneo model mimics the vascular disease observed in MFS patients. Furthermore, the study indicates role of thoracic spine deformity in the development of aorta diseases. We suggest that degradation of support structures of the aortic wall; deficiency in the sustenance of the thoracic vertebrae; and their compression over the adjacent aorta resulting in disturbed blood flow is a triad of factors involved in the genesis of dissection/aneurysm of thoracic aorta.
Assuntos
Aneurisma da Aorta Torácica , Síndrome de Marfan , Coluna Vertebral , Animais , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Aorta Torácica/fisiopatologia , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/metabolismo , Aneurisma da Aorta Torácica/patologia , Velocidade do Fluxo Sanguíneo , Modelos Animais de Doenças , Tecido Elástico/metabolismo , Feminino , Humanos , Síndrome de Marfan/genética , Síndrome de Marfan/metabolismo , Síndrome de Marfan/patologia , Camundongos , Camundongos Transgênicos , Coluna Vertebral/metabolismo , Coluna Vertebral/patologiaRESUMO
Ferret enteric coronavirus (FECV) is associated to the epizootic catarrhal enteritis (ECE) in ferrets (Mustela putorius furo). In this study, we report the occurrence of this agent in four diarrheic stool samples of domestic ferrets, analyzed by negative staining transmission electron microscopy and a specific RT-PCR assay targeting the nucleocapsid (N) gene. These findings are the first report of FECV in Brazil and address the importance of this virus on the etiology of enteric disorders in ferrets.
Coronavírus entérico de furões (FECV) é associado à enterite catarral epizoótica (ECE) em furões (Mustela putorius furo). Neste estudo, relatamos a ocorrência deste agente em quatro amostras fecais diarreicas de furões domésticos, analisadas por microscopia eletrônica de transmissão (contrastação negativa) e RT-PCR específica e direcionada ao gene de nucleocapsídeo (N). Estes achados constituem o primeiro relato de FECV no Brasil e remetem para a importância deste vírus na etiologia de quadros entéricos nestes animais.