RESUMO
Presentamos un caso de tumor glioneuronal formador de rosetas del iv ventrículo observado en un adolescente de 14 años, sin antecedentes clínicos de interés. El paciente presentó un cuadro de hidrocefalia obstructiva y se le detectó radiológicamente una lesión ocupante de espacio que afectaba al vermis cerebeloso y que obstruía el iv ventrículo. Los hallazgos histopatológicos mostraron un tumor de apariencia benigna, constituido por estructuras rosetoides centradas por un material fibrilar acidófilo. Dicho tumor fue positivo tanto para marcadores neuronales (sinaptofisina y enolasa) como gliales (PGFA). Tras la descripción, se comentan brevemente las principales características de esta rara entidad (AU)
We present a case of a rosette-forming glioneuronal tumour of the fourth ventricle in a 14-year-old with no relevant previous clinical history. The patient presented with hypertensive hydrocephalus and radiology revealed a space-occupying lesion affecting the cerebellar vermis and obstructing the fourth ventricle. The tumour was removed and was seen to have a benign appearance and to be formed of rosette-like structures composed of acidophilic fibrillary material. It was positive for neuronal markers (synaptophysin and enolase) and glial markers (GRAP). The main features of this rare entity are discussed (AU)
Assuntos
Humanos , Masculino , Adolescente , Neoplasias do Ventrículo Cerebral/patologia , Vermis Cerebelar/patologia , Formação de Roseta/efeitos adversos , Ventrículos Cerebrais/patologia , Marcadores do Trato Nervoso/análise , Imageamento por Ressonância Magnética/métodos , Neoplasias do Ventrículo Cerebral/cirurgia , Imuno-Histoquímica/métodosAssuntos
Neoplasias Encefálicas/patologia , Exoftalmia/patologia , Transtornos da Visão/patologia , Acuidade Visual/fisiologia , Idoso , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/cirurgia , Exoftalmia/complicações , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos da Visão/etiologiaRESUMO
The expression of brain derived neurotrophic factor (BDNF) and its preferred receptor (TrkB) in rat retinal ganglion cells (RGCs) have been determined in the present study. To identify RGCs retrograde labelling was performed with fluorogold (FG). Subsequently, retinas were immunostained with antibodies to BDNF and TrkB. We found that all RGCs labelled with FG express both BDNF and its preferred receptor, TrkB. Moreover, displaced amacrine cells were also found to be immunolabelled by both antibodies. Thus BDNF/TrkB signalling in RGCs probably involves endogenous BDNF produced by the RGCs themselves.
