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ABSTRACT: Clinical use of autologous induced pluripotent stem cells (iPSCs) could circumvent immune rejection and bioethical issues associated with embryonic stem cells. Spinal cord injury (SCI) is a devastating trauma with long-lasting disability, and current therapeutic approaches are not satisfactory. In the present study, the authors used the neural stem sphere (NSS) method to differentiate iPSCs into astrocytes, which were evaluated after their transplantation into injured rat spinal cords.
Induced pluripotent stem cell-derived astrocytes were differentiated using the NSS method and injected 3 and 7 days after spinal contusion-based SCI. Control rats were injected with DMEM in the same manner. Locomotor recovery was assessed for 8 weeks, and sensory and locomotion tests were evaluated at 8 weeks. Immunohistological parameters were then assessed.
Transplant recipients lived for 8 weeks without tumor formation. Transplanted cells stretched their processes along the longitudinal axis, but they did not merge with the processes of host GFAP-positive astrocytes. Locomotion was assessed in 3 ways, but none of the tests detected statistically significant improvements compared with DMEM-treated control rats after 8 weeks. Rather, iPSC transplantation caused even greater sensitivity to mechanical stimulus than DMEM treatment.
Astrocytes can be generated by serum treatment of NSS-generated cells derived from iPSCs. However, transplantation of such cells is poorly suited for repairing SCI.
Journal of neurosurgery. Spine 08/2011; 15(6):582-93. · 1.61 Impact Factor
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ABSTRACT: To assess the acute cardiovascular response to aquatic exercise in patients with osteoarthritis.
Blood pressure (BP) and heart rate (HR) were measured in 13 female patients with osteoarthritis (63.3 +/- 8.4 yrs) during aquatic walking for 40 mins. A double product (DP) value was calculated by multiplying systolic BP by HR to evaluate the workload of the heart.
BP and DP increased transiently with a decrease in HR after water immersion. Aquatic walking induced increases in BP, DP, and HR. Furthermore, BP and DP increased sharply with an increase in HR on leaving the water. The mean maximum increases in systolic BP and DP during each process were 23.5 +/- 18.2 mm Hg and 2931.1 +/- 2758.5 mm Hg/min when entering the water, 36.5 +/- 16.5 mm Hg and 4557.2 +/- 3435.1 mm Hg/min during aquatic walking, and 38.5 +/- 18.9 mm Hg and 5132.3 +/- 3228.8 mm Hg/min on leaving the water.
Water immersion, aquatic walking, and the process of leaving the water induced marked increases in BP in patients with osteoarthritis.
American journal of physical medicine & rehabilitation / Association of Academic Physiatrists 09/2010; 89(9):731-5. · 1.56 Impact Factor
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ABSTRACT: In light of reports that the administration of fasudil, a Rho-kinase inhibitor, improved rats locomotor abilities following spinal cord injury, we hypothesized that combining fasudil with another type of therapy, such as stem cell transplantation, might further improve the level of locomotor recovery. Bone marrow stromal cells (BMSCs) are readily available for stem cell therapy. In the present study, we examined whether fasudil combined with BMSC transplantation would produce synergistic effects on recovery. Adult female Sprague-Dawley rats were subjected to spinal cord contusion injury at the T10 vertebral level using an IH impactor (200 Kdyn). Immediately after contusion, they were administrated fasudil intrathecally for 4 weeks. GFP rat-derived BMSCs (2.5x10(6)) were injected into the lesion site 14 days after contusion. Locomotor recovery was assessed for 9 weeks with BBB scoring. Sensory tests were conducted at 8 weeks. Biotinylated dextran amine (BDA) was injected into the sensory-motor cortex at 9 weeks. In addition to an untreated control group, the study also included a fasudil-only group and a BMSC-only group in order to compare the effects of combined therapy vs. single-agent therapy. Animals were perfused transcardially 11 weeks after contusion, and histological examinations were performed. The combined therapy group showed statistically better locomotor recovery than the untreated control group at 8 and 9 weeks after contusion. Neither of the two single-agent treatments improved open field locomotor function. Sensory tests showed no statistically significant difference by treatment. Histological and immunohistochemical studies provided some supporting evidence for better locomotor recovery following combined therapy. The average area of the cystic cavity was significantly smaller in the fasudil+BMSC group than in the control group. The number of 5-HT nerve fibers was significantly higher in the fasudil+BMSC group than in the control group on the rostral side of the lesion site. BDA-labeled fibers on the caudal side of the lesion epicenter were observed only in the fasudil+BMSC group. On the other hand, only small numbers of GFP-labeled grafted cells remained 9 weeks after transplantation, and these were mainly localized at the site of injection. Double immunofluorescence studies showed no evidence of differentiation of grafted BMSCs into glial cells or neurons. The Rho-kinase inhibitor fasudil combined with BMSC transplantation resulted in better locomotor recovery than occurred in the untreated control group. However, the data failed to demonstrate significant synergism from combined therapy compared with the levels of recovery following single-agent treatment.
Brain research 08/2009; 1295:192-202. · 2.46 Impact Factor
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ABSTRACT: Anoikis is a type of apoptosis due to the detachment from the extracellular matrix and neighboring cells. In case of cell transplantation therapy for spinal cord injury, preparation of graft cells includes dissociation of cultured cells, which may cause anoikis-induced cell death. Thus suppression of anoikis may increase survival of grafted cells. Here we tested the effect of brain-derived neurotrophic factor (BDNF) on anoikis-induced cell death of cultured Schwann cells. Schwann cells were collected and cultured from sciatic nerves of neonatal Wistar rats. Schwann cells were plated upon a non-adherent polyhydroxyethyl methacrylate substrate to induce anoikis. BDNF was added into the culture medium at various concentrations. Twenty-four hours after non-adherent culture, approximately 40% of Schwann cells died and BDNF significantly decreased the number of dead cells in that culture condition. Next, Schwann cells were transplanted with or without BDNF treatment into contused rat spinal cord 1 week after injury. Five weeks after transplantation, immunohistochemistry revealed that the number of transplanted cells was significantly larger in the BDNF-treated group than that of the non-treated group. Suppression of anoikis may increase survival of grafted cells in case of cell therapy for spinal cord injury.
Neuroscience Letters 08/2008; 444(2):143-7. · 2.11 Impact Factor
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ABSTRACT: The purpose of this study was to use a cDNA microarray to identify new genes involved in healing of spinal cord injury. C57BL/6 mice (7-8 weeks, male) were subjected to spinal cord compression injury (SCI) at the T7/8 level (20 g, 5 min; SCI group). For the control group, mice underwent only laminectomy. Mice were killed at 1, 3 and 7 days. cDNA transcribed from mRNA was hybridized to NIA mice 15K microarrays at each time point. We found 84 genes showing significant expressional changes, including higher and lower expression levels in the SCI groups than in the control [more than 1.0 or less than -1.0 using log ratio (base 2)]. Five genes were selected for further quantitative gene expression analysis by real-time reverse transcription (RT)-PCR. For histological examination, we applied in situ hybridization and fluorescence immunohistochemistry. Cathepsin D, metallothionein-1 (MT-1), metallothionein-2 (MT-2), osteopontin (OPN), and tenascin-C were selected for quantitative and histological analysis. Microarray analysis revealed that SCI led to the up-regulation of OPN and cathepsin D expression at 7 days and also of MT-1, MT-2, and tenascin-C expression at 1 day. Tenascin-C was re-up-regulated at 7 days. These values agreed with those of real-time RT-PCR analysis. By double labeling with in situ hybridization and fluorescence immunohistochemistry, MT-1, MT-2 and tenascin-C expression was observed in neurons and glial cells at 1 day, whereas at 7 days the main MT-2 and tenascin-C expression was found in fibronectin-positive fibroblasts. The main cathepsin D and OPN expression was observed in activated macrophages/microglia at 3 and 7 days. The five genes picked up by microarray gene expression profiling were shown to exhibit temporal and spatial changes of expression after SCI. This system is potentially useful for identifying genes that are involved in the response to SCI.
Acta Neuropathologica 03/2005; 109(2):165-80. · 9.32 Impact Factor
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ABSTRACT: Spinal cord evoked potentials elicited by direct stimulation of the spinal cord were monitored in 21 patients during thoracic or thoraco-abdominal aortic aneurysm surgery. Flexible catherer-type electrodes were used for both stimulating and recording. The basic pattern of the spinal cord evoked potential consisted of an initial spike and a subsequent polyphasic component. The earliest and most frequent alterations after cross-clamping of the aorta were changes in the configuration or amplitude of the polyphasic component. In 13 patients who exhibited no change except minor alterations of the polyphasic component during the initial test clamping for 15 or 20 min, subsequent graft replacements were safely performed without reimplantation of intercostal vessels. In 2 patients who had sudden cardiac arrests, the evoked potential completely disappeared. The polyphasic component disappeared first, followed by the initial spike. Another patient developed acute loss of the potential after the aneurysm was incised, presumably due to distal aortic hypoperfusion. In this case, prolonged distal hypotension resulted in flaccid paraplegia.Intraoperative monitoring of the spinal cord evoked potential is a useful method for the early detection of spinal cord ischemia during surgery requiring aortic occlusion.
Electroencephalography and Clinical Neurophysiology/Evoked Potentials Section.
