Medulloblastomas represent the most common central nervous system malignancies in children. Despite intensive modality treatment with craniospinal irradiation and multiple drug chemotherapy, their prognosis remains dismal. In the present study, we examined the potential roles of cellular differentiation, proliferation and apoptosis in 21 pediatric patients with newly diagnosed classic medulloblastomas treated by conventional radiation therapy and adjuvant chemotherapy. The expression of glial fibrillary acidic protein, S-100, synaptophysin, TrkA and TrkC, and the proliferation index of MIB-1 were evaluated by immunohistochemistry and the apoptotic index was determined using terminal deoxytransferase-mediated deoxyuridine-5'-triphosphate nick-end labeling assay. The prognostic value of these biological markers was also assessed. Immunoreactive glial fibrillary acidic protein, S-100, synaptophysin, TrkA and TrkC were observed in seven (33%), four (19%), 12 (57%), 14 (67%) and 11 (52%) of the 21 cases, respectively. TrkA expression was positively correlated with the MIB-1 staining index (P = 0.0228) and the apoptotic index (P = 0.0058). None of the immunohistochemical markers was found to be of value in predicting the prognosis. Although the present small sample size does not provide sufficient power to discount biological variables as prognostic markers, it was the well-established clinical prognostic factors, i.e. tumor stage and extent of surgery, that stood out as the most important predictors of survival. The close association between apoptosis and TrkA expression is consistent with in vitro data demonstrating the capacity of the NGF/TrkA signaling pathway to increase medulloblastoma apoptotic cell death, suggesting that this pathway may yield alternative therapeutic targets for novel therapies.

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. -The interlayer space of layered Ni-Zn mixed basic salt can be controlled precisely by the intercalation of various carboxylate anions. The butyrate anion-exchanged NiZn catalyst promotes effectively the base-catalyzed Knoevenagel condensation in water and is reusable without loss of activity or selectivity. -(HARA, T.; KURIHARA, J.; ICHIKUNI, N.; SHIMAZU*, S.; Chem.

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Intraoperative monitoring techniques for protecting the integrity of the oculomotor nerves during skull base surgery have been reported by several investigators, all of which involved the use of electromyographic responses to extraocular muscles. However, these techniques have not yet become popular because of the complexity of the procedures. The authors report an extremely simple and far more reliable technique in which electrooculographic (EOG) monitoring is used. The oculomotor nerves were stimulated with a monopolar electrode during skull base exposure. The polarity of the EOG responses recorded with surface electrodes placed on the skin around the eyeball yielded precise information concerning the location and function of the oculomotor and abducent nerves. In addition, with the aid of continuous EOG monitoring that detected transient changes in the background waves, surgical procedures that might impinge on oculomotor nerve function could be avoided. The present technique has been used in eight patients with skull base tumors and with it, the authors have achieved excellent results.