Human umbilical cord-derived mesenchymal stromal cells (UC-MSCs) that are available from cell banks can be induced to differentiate into various cell types, thereby making them practical potential sources for cell-based therapies. In injured peripheral nerves, Schwann cells (SCs) contribute to functional recovery by supporting axonal regeneration and myelin reconstruction. Here, we first demonstrate a system to induce UC-MSCs to differentiate into cells with SC properties (UC-SCs) by treatment with β-mercaptoethanol followed by retinoic acid and a set of specific cytokines. The UC-SCs are morphologically similar to SCs and express SC markers, including P0, as assessed by immunocytochemistry and reverse transcription polymerase chain reaction. Transplantation of UC-SCs into transected sciatic nerves in adult rats enhanced nerve regeneration. The effectiveness of UC-SCs for axonal regeneration was comparable to that of authentic human SCs based on histological criteria and functional recovery. Immunohistochemistry and immunoelectron microscopy also demonstrated myelination of regenerated axons by UC-SCs. These findings indicate that cells with SC properties and with the ability to support axonal regeneration and reconstruct myelin can be successfully induced from UC-MSCs to promote functional recovery after peripheral nerve injury. This system may be applicable for the development of cell-based therapies.

No abstract

Background:There are no established treatment procedures for repeatedly recurring chronic subdural hematoma (CSH). In this study, we discussed the efficacy of middle meningeal artery (MMA) embolization in preventing recurrence of CSH.Methods:We performed superselective angiography of MMA in four patients who suffered from repeated recurrence of CSH. After angiography, we performed embolization of MMA with endovascular procedure.Results:In all cases, superselective angiography of MMA revealed diffuse abnormal vascular stains that seemed to represent the macrocapillaries in the outer membrane of CSH. In all the patients, there were no recurrences or enlargements of CSH after the embolization of the MMA.Conclusion:MMA embolization can be an effective adjuvant procedure in preventing the recurrence of CSH.

The purpose of the study was to assess the signal intensities of arachnoid granulations within the dural sinuses using the FLAIR sequence for differentiation of space-occupying lesions in and adjacent to the dural sinuses. We retrospectively reviewed MR images of the brain of 1118 consecutive subjects, ranging in age from 0 to 93 years (mean 57.2 years). Nodules within the dural sinuses with signal intensities similar to that of cerebrospinal fluid (CSF) on both T1 and T2 weighted images were defined as arachnoid granulations. The location, signal intensity on T1 weighted spin echo (SE), T2 weighted fast SE and FLAIR images, the impression on the inner table of the skull, and the size of the lesion were assessed. 112 subjects (10.0%), age range 4-89 years old (mean 58.9 years), were found to have 134 arachnoid granulations. The commonest location was the transverse sinus, with 115 granulations (85.8%). The prevalence of the granulations showed a peak in the sixth decade of age. All granulations were isointense relative to CSF on T2 weighted images and almost all lesions were isointense relative to CSF on T1 weighted images. On FLAIR images, 90.3% of the granulations were isointense relative to CSF and the other 9.7% granulations were slightly hyperintense compared with the CSF. 21 (15.7%) subjects showed impressions on the inner table; one case involved the outer table. In conclusion, arachnoid granulations were isointense or slightly hyperintense relative to CSF on FLAIR. FLAIR images are helpful in differentiating arachnoid granulations from other dural sinus lesions or skull lesions which have an intensity similar to that of CSF on T1 weighted and T2 weighted images.