Olfactory neuroepithelium in the superior and middle turbinates: which is the optimal biopsy site?

INTRODUCTION: Olfactory neuroepithelium (ON) biopsy has several therapeutic applications for both disorders of olfaction and neurodegenerative diseases. Successful collection of ON is still anything but routine due to a dearth of studies on the distribution of ON in the superior and middle turbinates. AIM: To determine the location in which ON is most likely to be present in endoscopically removed cadaver superior and middle turbinates as well as the influences of gender, age, and naris side on the presence of ON and the extent to which it is present. METHODS: We conducted a prospective anatomical study. The superior and middle turbinates on both sides endoscopically removed from 25 fresh cadavers (less than 12 h post-mortem). The turbinates were halved into anterior and posterior segments for a total of 200 specimens, which were analyzed after hematoxylin and eosin and immunohistochemical staining. Hematoxylin and eosin-stained slides were subjected to blind examination by 3 independent pathologists, and the presence of ON was graded on a 5-point scale from 0 to 4. Kappa measurement was used to determine the agreement between pairs of observers. RESULTS: ON was present in 82.9% of superior turbinate samples and in 17.1% of middle turbinate samples. Immunohistochemistry detected ON in superior turbinates only by S-100 staining and only in 15 fragments. Gender, age, and naris side had no statistically significant effects on the presence of ON. CONCLUSION: When biopsying ON, the posterior portion of the superior turbinate should be targeted whenever possible because it has the highest concentration of ON among the nasal structures.

Vascularização na cirrose hepática: estudo imunoistoquímico baseado em necropsias / Vascularization in hepatic cirrhosis: an immunohistochemical study on necropsies

RACIONAL: O processo patológico mais discutido na gênese da cirrose hepática é a fibrose progressiva, porém alterações na vasculatura do órgão têm sido apontadas como elementos fundamentais na fisiopatologia da doença e de suas complicações, como hipertensão portal, insuficiência hepática e carcinoma hepatocelular. OBJETIVO: Avaliar a densidade microvascular em 35 casos de necropsias de pacientes com cirrose hepática mediante pesquisa imunoistoquímica do marcador endotelial CD34 a fim de comparar os informes obtidos mediante semi-quantificação com aqueles registrados por método quantitativo morfométrico, além de relacionar as alterações vasculares encontradas com os principais agentes causais, padrões de lesão e complicações clínicas da doença. MÉTODOS: Foram estudados 35 casos de cirrose obtidos retrospectivamente de necropsias realizadas no SVOC/USP no período de março de 2002 a junho de 2003. Os casos foram reagrupados segundo padrão anatomopatológico em esteatohepatite e hepatite crônica. A microvasculatura foi avaliada através da reação imunoistoquímica com anticorpo anti-endotelio clone CD34, QBend. RESULTADOS: Observou-se associação significativa entre a abordagem semi-quantitativa e a quantificação morfométrica da densidade de vasos no parênquima, o mesmo não ocorrendo no septo. Não foram detectadas associações específicas entre a neovascularização e os tipos de complicação da hepatopatia aqui estudados. O principal achado foi que a neoformação vascular no parênquima é significantemente maior nas cirroses associadas a hepatites crônicas do que nas esteatohepatites. CONCLUSÃO: Todos esses achados requerem necessários estudos clínicos para avaliar a hipótese de que o estudo do rearranjo da microcirculação hepática, através de marcadores como o CD34, pode ser fator prognóstico em pacientes cirróticos.

BAKGROUND: Fibrosis has been the most cited variable in cirrhosis, but major alterations in hepatic vascularization have been pointed as basic elements in the physiopathology of the illness and its complications as portal hypertension, hepatic failure and hepatocellular carcinoma. METHODS: The present study aims at assessing microvascular density in 35 cases of necropsies of cirrhotic patients by immunohistochemical detection of endothelial marker CD34, comparing semi-quantification with morphometric quantitative method, also searching for a possible relation of vascular alterations with the main causal agents, injury patterns and major clinical complications. RESULTS: A significant association was detected between semi-quantitative and quantitative approach of microvessel density in parenchyma, but not in septa. No significant association was detected between neovascularization and any specific clinical complication of cirrhosis. Under our standpoint, the main achievement of the present study was the demonstration that the vascular neoformation in hepatic parenchyma is significantly higher in cirrhosis associated with chronic hepatitis than in cirrhosis resulting from steatohepatitis. CONCLUSION: These findings require further clinical studies to assess the hypothesis that the rearrangement of liver microcirculation through the detection of CD34 might be relevant in prognostic assessment of cirrhotic patients.

Stent coronário de liga cobalto-cromo concebido no Brasil: achados histológicos preliminares em modelo experimental porcino / Cobalt-chromium coronary stent conceived in Brazil: preliminary histologic findings in an experimental porcine model

Introdução: Este estudo objetiva avaliar em modelo experimental porcino um novo e pioneiro stent tubular de liga cobalto-cromo e de hastes finas, de concepção brasileira. Objetiva também relatar a experiência inicial de um centro de validação pré-clínica de dispositivos endovasculares instalado no País. Método: No total, 12 porcos domésticos foram submetidos a implante coronário de um novo stent de liga cobalto-cromo não-farmacológico (Scitech Produtos Médicos Ltda.). O stent possuía desenho em anéis corrugados com células curtas (aumento da homogeneidade da cobertura metálica), hastes finas (75μm) e ângulo inter-hastes idealizado para otimizar a força radial. A ligação interanel foi feita por meio de links curtos em formato sinusóide e espessura muito fina (65μm), com espaço circunferencial de 6 mm de diâmetro para acesso a ramo lateral. Dois outros animais receberam stents convencionais de controle para comparação (Driver®, Medtronic Inc., e Matrix®, Sahajanand Medical Technologies). Após um mês, os stents implantados foram retirados para análise microscópica. Resultados: Tanto o stent-teste como os stents comerciais de controle apresentaram hiperplasia neo-intimal discreta a moderada aos 30 dias, com obstrução neo-intimal de 30,0 + 12,2% e 22,4 + 16,5%, respectivamente. Todos os stents, no grupo stentteste e no grupo controle, encontravam-se com alto grau de endotelização, com discreto infiltrado inflamatório e persistência de fibrina discreta ou ausente. Conclusões: Esses achados sugerem que, do ponto de vista da resposta vascular ao implante, o novo stent apresentou desempenho semelhante ao de outros stents não-farmacológicos atualmente em uso comercial.

Background: This study aims to evaluate, in an experimental porcine model, a new and pioneer cobalt-chromium thin-strut coronary stent conceived in Brazil. Also, it aims to report the initial experience of a Brazilian center for pre-clinical validation of endovascular devices. Method: The new bare Cobalt-Chromium stent (Scitech Produtos Médicos Ltda) was implanted in the coronary arteries of twelve domestic pigs. The stent was designed in short rings (for increased homogeneity of vessel scaffolding), thin struts (75 μm) and inter-strut angle engineered to optimize the radial strength. The inter-ring connection was made by a short and very thin link (65 μm) in a curved format, with a circumferential diameter of 6 mm for side branch access. Another two animals received conventional bare metal stents as controls (Driver®, Medtronic Inc., e Matrix®, Sahajanand Medical Technologies). After one month, the implanted stents were excised for microscopic analysis. Results: Both the test-stent and the control commercial stents had mild to moderate neointimal hyperplasia at 30 days, with a neointimal percent obstruction of 30.0 ± 12.2% and 22.4 ± 16.5%, respectively. All stents, in the test-stent and the control groups, had a high degree of endothelialization with a mild inflammatory reaction and absent or mild persistence of fibrin. Conclusions: The present findings suggest that, as regards to the vascular reaction to the implant, the new stent presents a similar performance compared to other bare metal stents currently available for commercial use.