Intradural extramedullary spinal ependymomas are extremely rare. Herein, we describe a lesion-type spinal ependymoma that followed a malignant course, and discuss its clinical presentation, etiopathogenesis, and treatment. We present a patient who was diagnosed with an intradural extramedullary spinal tumor at T4-T6. The patient underwent gross total resection of the tumor without damage to the spinal cord. Histological examination, classified the lesion as a World Health Organization (WHO)-grade 2 ependymoma. One and a half years later, magnetic resonance imaging detected a recurring tumor at T4-T5. The tumor was removed and classified as a WHO-grade 3 anaplastic ependymoma. The patient was started on a course of regional spinal cord radiotherapy. The patient achieved tumoral control and clinical stabilization after the recurrence. We must consider the differential diagnosis of intradural extramedullary spinal tumors. The best treatment for this lesion is gross total resection and adjunctive radiotherapy is necessary in cases of malignant-change.
The olfactory epithelial layer contains multipotent horizontal basal cells (HBCs) that differentiate into olfactory sensory neurons. Here, we show that rat HBCs express oligodendrocyte progenitor cell (OPC) and astrocyte markers. We generated olfactory sphere (OS) cells in cultures that were derived from adult rat olfactory mucosa. Fluorescence-activated cell sorting and immunofluorescence analyses showed that OS cells also express OPC and astrocyte markers. Interestingly, OS cells underwent oligodendrocyte differentiation in vitro. To study oligodendrocyte differentiation in vivo, OS cells were transplanted into injured rat spinal cords. The transplanted cells integrated into host tissue and differentiated into oligodendrocytes. When transected saphenous nerve ends were encased in collagen-containing silicone tubes with or without OS cells, the transplanted OS cells differentiated into Schwann cells. Our data provide new insights into of the stemness of OS cells.
Spreading depression-like peri-infarct depolarizations not only characterize but also worsen penumbra conditions in cortical border zones of experimental focal ischemia. We intended to investigate the relevance of ischemic depolarization in subcortical regions of ischemic territories.Calomel We conclude that in focal ischemia, transient peri-infarct depolarizations emerge not only in cortical but also in striatal gray matter, thereby demonstrating the existence of subcortical zones of ischemic penumbra. The generation of these ischemic depolarizations is a multifocal process possibly linked to brain swelling and intracranial pressure rise in the later course of focal ischemia, and therefore a relevant correlate of progressively worsening conditions.
Novices using this unique webcam trainer showed improvement in psychomotor skills for EES. The authors believe that training in terms of basic endoscopic skills is meaningful and that the webcam training system can play a role in daily off-the-job training for EES.
Olfactory stem cells are generated from olfactory mucosa. Various culture conditions generate olfactory stem cells that differ according to species and developmental stage and have different progenitor or stem cell characteristics. Olfactory spheres (OSs) are clusters of progenitor or stem cells generated from olfactory mucosa in suspension culture. In this study, adult human OSs were generated and their characteristics analyzed. Human OSs were adequately produced from olfactory mucosa with area over 40 mm(2). Immunocytochemistry (ICC) and fluorescence-activated cell sorting showed that human OSs were AN2 and A2B5-positive. Immunofluorescence analysis of cell type-specific ICC indicated that the number of Tuj1-positive OS cells was significantly elevated. Tuj1-positive cells displayed typical neuronal soma and dendritic morphology. Human OS cells were also immunopositive for MAP2. By contrast, few RIP-, O4-, and GFAP-positive cells were present. These RIP, O4, and GFAP-positive cells did not resemble bona fide oligodendrocytes and astrocytes morphologically. In culture to induce differentiation of oligodendrocytes, human OS cells also expressed neuronal markers, but neither oligodendrocyte or astrocyte markers. These findings suggest that human OS cells autonomously differentiate into neurons in our culture condition and have potential to be used as a cell source of neural progenitors for their own regenerative grafts, avoiding the need for immunosuppression and ethical controversies.
Among the possible sources of autologous cells and tissues for use in spinal cord injury grafts, one promising source is the olfactory mucosa containing olfactory ensheathing cells and neural progenitor cells. Olfactory mucosa transplantation for spinal cord injury has been effective in animal models and in pilot clinical trials. However, the contributions of olfactory ensheathing cells and neurons in olfactory mucosa are unclear. For the present study, we prepared primary olfactory mucosal cells and used a cortex-Matrigel coculture assay system to examine the axonal outgrowth of olfactory mucosa. Axonal outgrowth from cortical slices was significantly enhanced in olfactory mucosal cells compared with noncell controls and respiratory mucosal cells, which have few olfactory ensheathing cells and neurons. Axonal outgrowth was severely reduced after treatment with an antineurotrophin cocktail. A conditioned medium in the olfactory mucosa-derived cell group contained neurotrophin-3. Some olfactory ensheathing cells and almost all neurons were immunopositive for neurotrophin-3. Axons originating from cortical slices targeted mainly the astrocyte-like olfactory ensheathing cells. Our findings demonstrate that the axonal outgrowth effect of olfactory mucosa is supported by both olfactory ensheathing cells and neurons in olfactory mucosa.
Bow hunter's stroke is typically due to mechanical compression or stretching of the dominant vertebral artery (VA) during contralateral head rotation against the bony elements of the atlas and axis. We report a case of vertebrobasilar insufficiency due to bilateral vertebral artery occlusion at the left C3-4 and the right C1-2 junction on rightward head rotation. A 64-year-old man experienced ischemic symptoms during 90°head rotation to the right with complete resolution of symptoms after returning his head to the neutral position. Dynamic cervical angiography with rightward head rotation showed severe compression of the right VA at the transverse foramen of C3-4 and mechanical stenosis of the left VA at the C1-2 level. During head rotation, the flow of the right VA was decreased more than the left side. Cervical 3-D computed tomography (CT) on rightward head rotation demonstrated displacement of the uncovertebral C3-4 joint, with excessive rotation of the C3 vertebral body. Based on these findings, instability at C3-4 was suspected to be the main cause of the vertebrobasilar insufficiency. Anterior discectomy and fusion at the C3/4 level were performed. Postoperatively, the patient experienced complete resolution of symptoms, and dynamic cervical angiography showed disappearance of the compression of the right VA. To our knowledge, this is the first reported case of bow hunter's stroke diagnosed by dynamic cerebral angiography and cervical 3-D CT without angiography, and treated by anterior decompression and fusion without decompression of the VA.
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