RESUMO
BACKGROUND: Actual challenge in surgical treatment of intra-axial gliomas involving eloquent areas is maximal safe resection. Mapping and monitoring of cortical and subcortical motor functionsare important tools to avoid postoperative deficits. In the present study, we present our experiencewith a continuous dynamic motor mapping technique pairing a traditional monopolar stimulatorwith a Cavitron Ultrasonic Surgical Aspirator (CUSA) to perform a continuous stimulation ofthe white matter avoiding removal interruption. METHODS: We describe a single center retrospective analysis of 1-year consecutive patients with intraxial tumors located adjacent to corticospinal tract and treated with surgical resection adopting "continuous dynamic mapping technique". With the support of a reconstruction software (3D Slicer), we classified the Extent Of Resection (EOR) as Gross Total Resection (GTR) (>98%), Sub-Total Resection (STR) (from 90% to 97%), and Partial Resection (<90%). Medical Research Council (MRC) grading was adopted to evaluate neurological outcomes (from 0 to 5), assessed on 1st post-operative day, at 1 week, 1 month and 3 months. RESULTS: From July 2017 to July 2018, 29 patients underwent to surgical removal of intraxial tumor adjacent to motor areas, using continuous dynamic subcortical mapping. Median age was 54 years old (range 12-75 years). At pre-operative MRI tractography reconstruction, mean distance between tumor and corticospinal tract was 4,4 mm (range At 1 week post-operative assessment, motor deficits were still present in 12 patients (41%). At 1 month, 10 patients (35%) had persisting deficits, which required admission to rehabilitation department. At 3 months, 4 patients (14%) had persistent motor impairment and overall 28 patients (98%) were able to walk by themselves. CONCLUSIONS: Our early experience showed that a combination of dynamic subcortical mapping with transcranial and cortical strip MEP (Motor Evoked Potentials) monitoring is useful in tumors close to motor eloquent areas to extend surgical resection avoiding permanent consequences. However, we need for further experience to consolidate and improve this technique.
RESUMO
To elucidate molecular mechanisms underlying oocyte senescence, we investigated whether oocytes from female mice of advanced reproductive age exhibit a precocious postovulatory aging that, in turn, may be responsible for the precocious activation of an apoptotic program. During a 9-h in vitro culture, the frequency of oocytes showing MII aberrations, spontaneous activation, and cellular fragmentation increased in old oocytes (P < 0.05), whereas it did not change in the young group. In old oocytes, the activities of MPF (a complex of the cyclin-dependent kinase cdc2 and cyclin B1) and MAPK (mitogen-activated protein kinase) decreased precociously, showing a first drop as early as 3 h after the beginning of in vitro culture (P < 0.05). Immunoblotting and immunocytochemical analysis revealed that, in oocytes of the old group, reduction of BCL2 expression at protein level occurred earlier than in the young group (P < 0.05) and was not associated to the loss of BCL2 transcripts detected by RT-PCR. These changes are followed by an abrupt increase of the rate of TUNEL-positive oocytes after 24 h of culture to a value of 67% +/- 6%. Exposure of young oocytes to 20 microM roscovitine or 20 microM U0126, specific inhibitors of MPF and MAPK, resulted in the decreased percentage of oocytes showing positive immunostaining for BCL2 and in an increased rate of DNA fragmentation. Present results suggest that the developmental competence of oocytes ovulated by aging mice may be negatively influenced by a downregulation of MPF and MAPK activities that in turn induces the activation of a proapoptotic signaling pathway.
