Cell therapy using stem cells is awaited by stroke patients with impaired movement and cognitive functions, although intravenous alteplase-administration ameliorated outcomes of patients receiving the therapy within 3 h of onset. In this study, we explored the therapeutic effects of neural progenitor cells (NPC) upon middle cerebral artery occlusion (MCAO) model of rats with exploration of the differences between adult and embryonic NPCs in therapeutic effects. GFP-labeled adult or embryonic NPCs were transplanted for transient MCAO model of rats at 1h after reperfusion. Rats were examined behaviorally using limb placement test, rotarod test and cylinder test with neuroradiological assessment using magnetic resonance imaging (MRI). Consequently after euthanasia, rats were immunohistochemically investigated to explore graft survival and immune reaction. MRI of rats receiving NPCs revealed significant reduction of infarct volumes, compared to vehicle-treated rats with corresponding behavioral amelioration. The transplanted cells were surviving in rats receiving NPCs, although the number of embryonic NPCs was significantly higher than that of adult NPCs. Iba-1-positive inflammatory cells of rats receiving adult NPCs were prominent, compared to those receiving embryonic NPCs, which might be a rationale for the differences between rats receiving adult and embryonic NPCs in the number of surviving NPCs. On the contraries, adult NPCs surely demonstrated therapeutic effects with a few surviving cells, thus indicating that the therapeutic effects might be due to trophic/growth factor-secretion from transplanted NPCs, rather than replacement of damaged host neurons. Therapeutic effects of NPCs for MCAO model of rats were clarified in this study. Transplantation of NPCs will be a hopeful strategy for stroke patients, although further studies are required for the patient safety and underlying mechanisms.

Meningiomas arising from the falcotentorial junction are extremely rare. The authors describe the clinical features, neuroimaging studies, and results of surgical treatment of meningiomas of the falcotentorial junction and clarify the characteristics of this lesion based on a review of the literature and seven patients treated at their institution. The most common symptoms resulted from intracranial hypertension. Upward-gaze palsy appeared in only one patient. Computerized tomography (CT) showed no specific findings, but there was no evidence of edema around the tumor. Magnetic resonance (MR) imaging revealed a round, smooth-bordered mass with a peritumoral rim, without edema, and showing marked contrast enhancement. The multiplanar capability of MR imaging delineated the relationship between the tumor and adjacent structures better than did CT. Detailed knowledge of the vascular structures, especially evidence of occlusion of the galenic venous system and the development of collateral venous channels, is critical for successful surgery; stereoscopic cerebral angiography is necessary to achieve this aim. The seven patients described developed five types of collateral venous channels: through the basal vein of Rosenthal to the petrosal vein, through the veins on the medial surface of the parietal and occipital lobes to the superior sagittal sinus, through superficial anastomotic veins, through veins of the posterior fossa to the transverse or straight sinus, and through the falcian veins to the superior sagittal sinus. The first three types mainly developed after occlusion of the galenic system. The tumors were removed through the occipital transtentorial approach with a large window at the posterior part of the falx. A favorable prognosis for patients undergoing surgical treatment of falcotentorial junction meningiomas can be expected if detailed neuroimaging studies and microsurgical techniques are used.

Summary:Purpose: In this study, we tried to show that EEG and magnetoencephalography (MEG) are clinically complementary to each other and that a combination of both technologies is useful for the precise diagnosis of epileptic focus.Methods: We recorded EEGs and MEGs simultaneously and analyzed dipoles in seven patients with intractable localizationrelated epilepsy. MEG dipoles were analyzed by using a BTI Magnes 148-channel magnetometer. EEG dipoles were analyzed by using a realistically shaped four-layered head model (scalp-skull-fluid-brain) built from 2.0-mm slice magnetic resonance imaging (MRI) images.Results: (a) In two of seven patients, MEG could not detect any epileptiform discharges, whereas EEG showed clear spikes. However, dipoles estimated from the MEG data corresponding to the early phase of EEG spikes clustered at a location close to that of the EEG-detected dipole. (b) In two of seven patients, EEG showed only intermittent high-voltage slow waves (HVSs) without definite spikes. However, MEG showed clear epileptiform discharges preceding these EEGdetected HVSs. Dipoles estimated for these EEG-detected HVSs were located at a location close to that of the MEGdetected dipoles. (c) Based on the agreement of the results of these two techniques, surgical resection was performed in one patient with good results.Conclusions: Dipole modeling of epileptiform activity by MEG and EEG sometimes provides information not obtainable with either modality used alone. Key Words: MEG-EEGLocalization-related epilepsy-Dipole.The dipole localization method has been widely used for noninvasive localization of spike foci (1-3). After the development of magnetoencephalography (MEG), most comparative studies of MEG and EEG have focused on comparing the localization accuracy of MEG and EEG dipoles (4,5). We addressed the way in which dipole localization with a combination of MEG and EEG supplements the information obtainable by either technique alone. We try to show that EEG and MEG are clinically complementary to each other, and that a combination of both technologies is useful for the precise diagnosis of epilepsy patients. PATIENTS AND METHODSSubjects were drawn from all the outpatients and inpatients of Okayama University Hospital who were being considered for antiepileptic surgery between July 2000 and June 2001. We obtained consent from the parents of seven of these patients to perform MEG investigation at the Okayama Ryogo Center. The patients consisted of six boys and one girl (average age, 15 years and 1 month; range, 5 years and 7 months to 19 years and 2 months). All the patients had intractable localizationrelated epilepsy.We recorded EEGs and MEGs simultaneously. MEGs were recorded with a 148-channel whole-head magnetometer (BTI Magnes, San Diego, CA, U.S.A.) with simultaneous 21-channel EEG recording by using the international 10-20 system with additional electrodes at Fpz and Oz referenced to the ears. The MEG and EEG sampling rates were 678.17 and 500 Hz. The MEG signal was filtered in real time with a highp...

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Deep brain stimulation (DBS) is used to treat a variety of neurological disorders including Parkinson's disease. In this study, we explored the effects of striatal stimulation (SS) in a rat model of chronic-phase ischemic stroke. The stimulation electrode was implanted into the ischemic penumbra at 1 month after middle cerebral artery occlusion (MCAO) and thereafter continuously delivered SS over a period of 1 week. Rats were evaluated behaviorally coupled with neuroradiological assessment of the infarct volumes using magnetic resonance imaging (MRI) at pre- and post-SS. The rats with SS showed significant behavioral recovery in the spontaneous activity and limb placement test compared to those without SS. MRI visualized that SS also significantly reduced the infarct volumes compared to that at pre-SS or without SS. Immunohistochemical analyses revealed a robust neurogenic response in rats that received SS characterized by a stream of proliferating cells from the subventricular zone migrating to and subsequently differentiating into neurons in the ischemic penumbra, which exhibited a significant GDNF upregulation. In tandem with this SS-mediated neurogenesis, enhanced angiogenesis was also recognized as revealed by a significant increase in VEGF levels in the penumbra. These results provide evidence that SS affords neurorestoration at the chronic phase of stroke by stimulating endogenous neurogenesis and angiogenesis.