Neuroimmune interactions underlying the development of pain sensitization in models of neuropathic pain have been widely studied. In this study, we evaluated the development of allodynia and its reduction associated with peripheral antineuroinflammatory effects induced by a dexamethasone-loaded biodegradable implant. Chronic constriction injury (CCI) of the sciatic nerve was performed in Wistar rats. The electronic von Frey test was applied to assess mechanical allodynia. The dexamethasone-loaded implant was placed perineurally at the moment of CCI or 12 days after surgery. Dorsal root ganglia (DRG; L4-L5) were harvested and nuclear extracts were assayed by Western blot for detection of nuclear factor (NF)-κB p65/RelA translocation. Dexamethasone delivered from the implant delayed the development of allodynia for approximately three weeks in CCI rats when the implantation was performed at day 0, but allodynia was not reversed when the implantation was performed at day 12. NF-κB was activated in CCI rat DRG compared with naïve or sham animals (day 15), and dexamethasone implant inhibited p65/RelA translocation in CCI rats compared with control. This study demonstrated that the dexamethasone-loaded implant suppresses allodynia development and peripheral neuroinflammation. This device can reduce the potential side effects associated with oral anti-inflammatory drugs.

Para melhorar a sensibilidade diagnóstica da eletrococleografia na doença de Ménière têm-se estudado novos métodos de mensuração. OBJETIVOS: Verificar se a técnica da medida angular gráfica é sensível e específica para o diagnóstico laboratorial da doença de Ménière e se existe incremento na sensibilidade e especificidade da eletrococleografia, quando da associação da medida angular gráfica com o valor da relação SP/AP. CASUÍSTICA E MÉTODO: Foram analisadas a eletrococleografia de 71 orelhas: 41 pacientes com diagnóstico clínico de doença de Ménière e 14 controles sadios. Os traçados foram analisados inicialmente para a obtenção do valor da relação SP/AP, posteriormente foi calculada a medida angular gráfica. RESULTADOS: O valor da sensibilidade e especificidade da medida angular, da relação SP/AP e da associação de ambas variou de acordo com o ponto de corte, os valores 166,25 para a medida angular e 27% para SP/AP foram os que demonstraram maior equilíbrio entre sensibilidade e especificidade, 62,79% / 60,71% e 74,42% / 67,86%, respectivamente. A associação das medidas mostrou incremento da sensibilidade à custa da diminuição da especificidade, 88,37% e 50%, respectivamente. CONCLUSÕES: A medida angular gráfica não é sensível e específica suficiente para o diagnóstico laboratorial DM. A associação da relação SP/AP e medida angular gráfica apresentou melhora da sensibilidade em detrimento da especificidade do exame.

To improve electrocochleography's diagnostic sensitivity in Meniére's disease - new assessment methods are being studied. AIM: To determine whether or not graphic angle measurement is sensitive and specific to Menière's disease laboratorial diagnosis and if there is an increase in the electrocochleography's sensitivity and specificity when graphic angle measurements are associated with Summating Potential-Action Potential ratio (SP/AP ratio). METHODS: Electrocochleography's was used to analyze 71 ears from 55 subjects: 41 patients with clinical diagnosis of Menière's disease (MD group), and 14 healthy individuals as control (Group C). Graphic results were analyzed initially to obtain the SP/AP ratio; afterwards, through another program graphic angle measurements were calculated. RESULTS: Sensitivity and specificity values of angle measures, SP/AP ratio, and the association between them varied according to the cutoff point, the highest equilibrium between sensitivity and specificity was observed with the values of 166.25 for angle measurement and 27% for SP/AP relation; 62.79% / 60.71% and 74.42% / 67.86%, respectively. The association between measurements showed a sensitivity increase due to the specificity decrease; 88.37% and 50%, respectively. CONCLUSION: Angle graphic measurement is not sensitive and specific enough for the laboratorial diagnosis of MD. Angle graphic measurement and SP/AP ratio association proved to be higher in sensitivity, in detriment of exam specificity.