Rintala Flap and Posterior Perichondrial Cutaneous Graft: A Combined Approach for Nasal Tip Reconstruction

Nasal tip reconstruction requires a meticulous approach due to the complexity of the nasal anatomy and its aesthetic importance. Many procedures have been described to restore this aesthetic unit, including the paramedian forehead flap, which is one of the workhorse flaps. However, despite excellent final outcomes, this procedure may be refused by patients, due to its temporary conspicuous appearance possibly associated with serious psychological implications, and the need of multiple interventions. We aimed to present an approach combining the Rintala flap and the posterior perichondrial cutaneous graft as a valuable alternative to treat large nasal tip defects.

Morphological characterization of ckd in cats: Insights of fibrogenesis to be recognized

Renal fibrosis is characterized by glomerulosclerosis and tubulointerstitial fibrosis and its pathogenesis is associated with the activity of mesenchymal cells (fibroblasts), being essentially characterized by a process of excessive accumulation resulting from the deposition of extracellular matrix components. The aim of this study was to characterize the morphological presentation of chronic and fibrotic lesions in the glomerular, tubular, interstitial, and vascular compartments in feline CKD, as well as the possible participation of myofibroblasts in renal fibrotic processes in this species. Cat kidneys were collected and processed according to the conventional techniques for light microscopy, circular polarization, immunohistochemistry, and electron microscopy. Fibrotic alterations were present in all compartments analyzed. The main findings in the glomerular compartment were different degrees of glomerular sclerosis, synechia formation, Bowman's capsule calcification, in addition to glomerular basement membrane thickening and pericapsular fibrosis. The tubulointerstitial compartment had intense tubular degeneration and the immunostaining in tubular cells for mesenchymal cell markers demonstrated the possibility of mesenchymal epithelial transition and consequent involvement of myofibroblasts in the development of interstitial tubule damage. Infiltration of inflammatory cells, added to vessel thickening and fibrosis, demonstrated the severity and role of inflammation in the development and perpetuation of damage. Thus, we may conclude that fibrotic lesions play a relevant role in feline CKD and the mechanism of perpetuation of these lesions need further elucidation regarding the origin and participation of myofibroblasts and consequent mesenchymal epithelial transition in this species.