SUMMARYPurpose: High-frequency oscillations (HFOs), termed ripples at 80-200 Hz and fast ripples (FRs) at >200/250 Hz, recorded by intracranial electroencephalography (EEG), may be a valuable surrogate marker for the localization of the epileptogenic zone. We evaluated the relationship of the resection of focal brain regions containing high-rate interictal HFOs and the seizure-onset zone (SOZ) determined by visual EEG analysis with the postsurgical seizure outcome, using extraoperative intracranial EEG monitoring in pediatric patients and automated HFO detection. Methods: We retrospectively analyzed 28 pediatric epilepsy patients who underwent extraoperative intracranial video-EEG monitoring prior to focal resection. Utilizing the automated analysis, we identified interictal HFOs during 20 min of sleep EEG and determined the brain regions containing high-rate HFOs. We investigated spatial relationships between regions with high-rate HFOs and SOZs. We compared the size of these regions, the surgical resection, and the amount of the regions with high-rate HFOs/ SOZs within the resection area with seizure outcome.Key Findings: Ten patients were completely seizure-free and 18 were not at 2 years after surgery. The brain regions with high-rate ripples were larger than those with high-rate FRs (p = 0.0011) with partial overlap. More complete resection of the regions with high-rate FRs significantly correlated with a better seizure outcome (p = 0.046). More complete resection of the regions with high-rate ripples tended to improve seizure outcome (p = 0.091); however, the resection of SOZ did not influence seizure outcome (p = 0.18). The size of surgical resection was not associated with seizure outcome (p = 0.22-0.39). Significance: The interictal high-rate FRs are a possible surrogate marker of the epileptogenic zone. Interictal ripples are not as specific a marker of the epileptogenic zone as interictal FRs. Resection of the brain regions with high-rate interictal FRs in addition to the SOZ may achieve a better seizure outcome.

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SUMMARYPurpose: We intended to elucidate the whole clinical course of Dravet syndrome (DS) comprehensively, from infancy through adulthood. Methods: Subjects were 31 patients with DS (14 with typical DS, and 17 with borderline DS) who were followed from childhood to at least 18 years of age. Their seizures, abilities, and electroencephalography (EEG) findings were investigated and statistically analyzed. Results: The clinical findings of the patients with typical DS and those with borderline DS became largely similar in adolescence and adulthood. Seizures were intractable in childhood in all patients, but suppressed in five (16.1%) during follow-up. Thirty-five (87.5%) of the 40 apparently generalized convulsive seizures that were captured by ictal EEG recording at 7 years of age or later were of focal origin. The seizure-free outcomes were significantly correlated with the experience of <3 episodes of convulsive status epilepticus, and also with disappearance of spikes on the follow-up EEGs. Mental outcomes involving less severe intellectual disability were correlated with the presence of occipital alpha rhythms in the background activity of the follow-up EEGs. Mean age at the recording of the follow-up EEGs was 23.8 years. Discussion: Prevention of the occurrence of convulsive status epilepticus was indicated to be critically important for the improvement of seizure prognosis in DS.

BackgroundMembranous nephropathy (MN) is the leading cause of nephrotic syndrome in adults. Anti-M-type phospholipase A2 receptor (anti-PLA2R) antibodies are found in most patients with idiopathic MN (iMN) worldwide, but the prevalence of anti-PLA2R antibodies among Japanese patients with MN is unknown. In this study, we determined the prevalence of anti-PLA2R antibodies in Japanese patients with MN.MethodsThe study population of our retrospective cross-sectional consisted of 131 patients with biopsy-proven MN who had not received any immunosuppressive treatments at time of both renal biopsy and serum sample collection. Of these, 100 had iMN and 31 had secondary MN (sMN). The circulating anti-PLA2R antibodies were analyzed using a highly sensitive Western blot analysis. Analysis was performed under non-reducing conditions with a human glomerular extract at serum dilutions of 1:25, 1:10, and 1 as the primary antibody.ResultsAnti-PLA2R antibodies were detected in 53 (53 %) of 100 patients with iMN and 0 (0 %) of 31 patients with sMN. The prevalence of anti-PLA2R antibodies was higher in patients with nephrotic syndrome (61 %) than in patients without nephrotic syndrome (43 %). The number of patients with serum albumin ≤3.0 g/dL was significantly higher in those with anti-PLA2R antibodies (92 %) than that in those without them (68 %).ConclusionsAnti-PLA2R antibodies were found in Japanese patients with iMN; however, the prevalence was lower than that of any other Asian country. This may indicate that the presence of other pathogenic antigens plays a significant role in Japanese patients with iMN.

To treat bone loss that is induced by disease or wounds, bone grafts are commonly used. In dentistry, guided tissue regeneration is effective in the treatment of periodontal diseases. However, bone resorption after implantation is a major problem with the bone graft and guided tissue regeneration technique. This study examines a cell pellet culture system without exogenous scaffolds for bone regeneration. First, we examined the effect of ascorbic acid on cells. Transmission electron microscopic observation revealed that cells formed a three-dimensional structure of multiple cell layers after 5 weeks of culturing in medium containing 50 µg/ ml ascorbic acid with the medium changed every 7 days. A single cell pellet was produced by centrifuging cells that were gathered from 10 tissue culture dishes. Van Gieson staining and collagen type I immunostaining showed that the pellet contained collagen fibers and cells that adhered to the collagen fibers. Several of these cell pellets were implanted subcutaneously on the backs of nude mice for 6 weeks. Histology and immunohistochemistry results indicated new bone formation, vascular invasion, and insular areas of calcification. Bone tissue was surrounded by osteoblasts. The appearance of new bone formation is similar to that seen in intramembranous ossification. The present pellet system is reliable and might solve problems of bone resorption after implantation.