ABSTRACT
ABSTRACT Rhinopathies diagnosis in small animals is challenging, especially regarding their etiology. Imaging exams are very valuable tools for diagnostic procedures. The objective here is to report a rare case of rhinitis by Microsporum canis in a 4-year-old male, SRD dog, sneezing and with chronic purulent nasal secretion two weeks after surgical correction of cleft palate, emphasizing the imaging tests importance for a final and assertive diagnosis. Skull radiographs revealed turbinate destruction and two soft tissue amorphous structures with radiopacity at nasal cavity. The presence of a foreign body in the left passage, soaked in mucopurulent secretion associated with fungal plaques, with firm texture were evidenced by rhinoscopy, and identified as M. canis colonies by microbiological examination. In association, red-brown hyperplastic areas biopsied via rhinoscopy were histologically diagnosed as transmissible venereal tumor. It is concluded that such infection can be reported as opportunistic, secondary to local immunosuppression by post-surgical foreign body and nasal TVT. This is the first case to report such a pathogen in the dog, making its insertion in the differential diagnosis of rhinopathies extremely valuable.
RESUMO O diagnóstico de rinopatias em pequenos animais é desafiador, especialmente quanto a sua etiologia. Exames de imagem são ferramentas de grande valia na condução diagnóstica. Objetiva-se relatar um caso raro de rinite por Microsporum canis, em um cão de quatro anos, macho, SRD, apresentando espirros e secreção nasal purulenta crônica, duas semanas após correção cirúrgica de fenda palatina, e enfatizar a importância dos exames de imagem no diagnóstico final e assertivo. Radiografias de crânio revelaram destruição dos turbinados e duas estruturas amorfas, de radiopacidade de tecidos moles em cavidade nasal. Presença de corpo estranho em passagem esquerda, embebido em secreção mucopurulenta, associada a placas fúngicas, de textura firme, foi evidenciada á rinoscopia, as quais foram identificadas como colônias de M. canis ao exame microbiológico. Em associação, áreas hiperplásicas vermelho-acastanhadas, biopsiadas via rinoscopia, foram diagnosticadas histologicamente como tumor venéreo transmissível. Conclui-se que tal infecção pode ser reportada como oportunista, secundária à imunossupressão local por corpo estranho pós-cirúrgico e TVT nasal. Este é o primeiro caso a reportar tal patógeno no cão, tornando de extrema valia a inserção deste no diagnóstico diferencial de rinopatias.
ABSTRACT
We present a cluster growth process that provides a clear connection between equilibrium statistical mechanics and an explosive percolation model similar to the one recently proposed by D. Achlioptas [Science 323, 1453 (2009)]. We show that the following two ingredients are sufficient for obtaining an abrupt (first-order) transition in the fraction of the system occupied by the largest cluster: (i) the size of all growing clusters should be kept approximately the same, and (ii) the inclusion of merging bonds (i.e., bonds connecting vertices in different clusters) should dominate with respect to the redundant bonds (i.e., bonds connecting vertices in the same cluster). Moreover, in the extreme limit where only merging bonds are present, a complete enumeration scheme based on treelike graphs can be used to obtain an exact solution of our model that displays a first-order transition. Finally, the presented mechanism can be viewed as a generalization of standard percolation that discloses a family of models with potential application in growth and fragmentation processes of real network systems.