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Objective: We analyzed the features of fast oscillations (FOs) and connectivity in hypsarrhythmia to identify biomarkers for predicting seizure outcomes after total corpus callosotomy (TCC) in children with pharmacoresistant infantile spasms (IS). We hypothesize that the power of FOs and connectivity of slow waves in hypsarrhythmia would indicate the prognosis of IS. Method: We retrospectively identified 42 children with pharmacoresistant IS who underwent TCC from 2009 to 2014 at Nagasaki Medical Center. We collected preoperative hypsarrhythmia for 200 seconds from each child. Children were categorized into three groups with interictal epileptic discharges on EEG at 6 months after TCC: group A, no epileptic discharge; group B, lateralized epileptic discharges; and group C; bilateral epileptic discharges. We analyzed spectral power and phase synchronization in preoperative hypsarrhythmia among the three groups. Results: We found 10 children in group A, 10 children in group B, and 22 children in group C. All group A and 1 in group B achieved seizure freedom after TCC. Six (67%) of 9 group B children who underwent further surgeries achieved seizure freedom. Ten (45%) of group C children had seizure reduction >50% after TCC, and 13 (87%) of 15 children who underwent further surgeries had residual seizures. The clinical profiles of the three groups did not differ significantly. The power of FOs (≥45 Hz) in hypsarrhythmia was significantly stronger in group C at the midline and temporal regions than in groups B and A (P = .014). The connectivity of theta (4‐9 Hz) and FOs (29‐70 Hz) tended to increase in group C, compared with the increased connectivity of 1‐2 Hz in group A (P = .08). Significance: The increased power and connectivity of FOs in hypsarrhythmia may correlate with pharmacoresistant and surgically resistant seizures in IS. The existence and connectivity of FOs are associated with unilateral/bilateral cortical epileptogenicity in hypsarrhythmia. Prominent slow waves and connectivity without FOs might correlate with seizure freedom after TCC. Modulation of the callosal system with subcortical/cortical epileptic discharges might play a role in generating hypsarrhythmia and IS. [ABSTRACT FROM AUTHOR]

We evaluated the effects on bone formation of combining synthesized collagen model polypeptides consisting of a Pro-Hyp-Gly [poly(PHG)] sequence and alpha-tricalcium phosphate (α-TCP) particles with various median sizes (large: 580.8 μm; small: 136.2 μm; or large and small mixed: 499.3 μm) in a skull defect model in mini-pigs. Quantitative image analyses for the volume density (VD) of new bone revealed that the VD in each α-TCP group was significantly higher than that in the poly(PHG) control group, with the mixed group showing the highest VD among all the groups at 4 weeks after implantation. Histological assessments revealed that the small α-TCP particles were almost completely degraded at 8 weeks. At 12 weeks, all sizes of α-TCP particles were completely degraded and remodeling of the lamellar bone was observed. The present findings suggest that particle size may influence the success of bone formation in defects. [ABSTRACT FROM AUTHOR]

To date, there has been no study on the development of novel regimens based on the following tissue engineering principles: seeding and culturing mesenchymal stem cells (MSCs) on a scaffold before surgery or injecting cultured MSCs into a scaffold during surgery. The purpose of this study was to assess the in viuo osteogenic ability of scaffold/MSCs implanted beneath the periosteum of the cranial bone of rats in three different sample groups: one in which MSCs were pre-seeded and cultured on a scaffold to produce the 3-D woven fabric scaffold/MSC composite using osteo-lineage induction medium, one in which cultured MSCs produced by osteo- lineage induction in cell cultivation flasks were injected into a scaffold during surgery and a control group, in which only the 3-D woven fabric scaffold was implanted. The results indicate that pre-seeding MSCs on a scaffold leads to a higher osteogenic ability than injecting cultured MSCs into a scaffold during surgery. [ABSTRACT FROM AUTHOR]