• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.122.2-122.2
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• 2016

Surface topographical cues has been highlighted to control the fate of neural stem cells (NSCs). Herein we developed a hierarchically patterned substrate (HPS) platform for regulating NSC differentiation. The HPS induced cytoskeleton alignment and highly activated focal adhesion in hNSCs as indicated by enhanced expression of focal adhesion proteins such as focal adhesion kinase (FAK) and vinculin. hNSCs cultured on HPS exhibited enhanced neuronal differentiation compared to flat group. We also developed a graphene oxide (GO)-based hierarchically patterned substrates (GPS) that promote focal adhesion formation and neuronal differentiation of hNSCs. Enhanced focal adhesion and differentiation of hNSCs on the HPS was reversed by blocking the ${\beta}1$ integrin binding and mechanotransduction-associated signals including Rho-associated protein kinase (ROCK) and extracellular-regulated kinase (ERK) pathway, which may suggest a potential mechanism of beneficial effects of HPS. In addition, hNSCs on the HPS differentiated into functional neurons exhibiting sodium currents and action potentials as confirmed by whole cell patch-clamping analysis. The hierarchical topography can direct differentiation of NSCs towards functional neurons, and therefore would be an important element for the design of functional biomaterials for neural tissue regeneration applications.

• The Journal of the Korea Contents Association
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• v.11 no.4
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• pp.273-282
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• 2011

This study was to investigate the effect of improve forelimb sensorimotor function and neurotrophic factor(GAP-43) expression when differing an application time of tDCS in ischemic brain injury rat model(pre, $1^{st}$, $7^{th}$, $14^{th}$). Focal ischemic brain injury was induced in 80 Sprague-Dawley rats through middle cerebral artery occlusion(MCAO) by 'Longa' method. And then experimental groups were randomly divided into four groups; GroupI: MCAO induction, GroupII: application of tDCS(10 min) after MCAO induction, GroupIII: application of tDCS(20 min) after MCAO induction, GroupIV: application of tDCS(30 min) after MCAO induction. Modified limb placing test and single pellet reaching test were performed to test forelimb sensorimotor function. And the histological examination was also observed through the immunohistochemistric response of GAP-43(growth-associated protein-43) in the cerebral cortex. In modified limb placing test, groupIII(p<0.05) showed significantly improve than the other groups on $14^{th}$). day. In single pellet reaching test, groupIII(p<0.01) and groupIV(p<0.05) significantly improved on $14^{th}$) day. And in immunohistochemistric response of GAP-43, group III showed significantly positive response than the other groups on $14^{th}$ day. These results suggest that the intensity(0.1 mA)/time(20 min) condition of tDCS application has a significant impact on the sensorimotor functional recovery in focal ischemic brain injury rat models.

• The Korean Journal of Pain
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• v.21 no.2
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• pp.119-125
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• 2008

Background: Cerebral blood vessels are innervated by sympathetic nerves from the superior cervical ganglia (SCG), and these nerves may influence the cerebral blood flow. The purpose of the present study was to evaluate the neuroprotective effect of superior cervical sympathetic ganglion block in rats that were subjected to focal cerebral ischemia/reperfusion injury. Methods: Eighty male Sprague-Dawley rats (270-320 g) were randomly assigned to one of two groups (the ropivacaine group and a control group). In all the animals, brain injury was induced by middle cerebral artery (MCA) reperfusion that followed MCA occlusion for 2 hours. The animals of the ropivacaine group received $30{\mu}l$ of 0.75% ropivacaine, and their SCG. Neurologic score was assessed at 1, 3, 7 and 14 days after brain injury. Brain tissue samples were then collected. The infarct ratio was measured by 2.3.5-triphenyltetrazolium chloride staining. The terminal deoxynucleotidyl transferase mediated dUTP-biotin nick-end labeled (TUNEL) reactive cells and the cells showing caspase-3 activity were counted as markers of apoptosis at the caudoputamen and frontoparietal cortex. Results: The death rate, the neurologic score and the infarction ratio were significantly less in the ropivacaine group 24 hr after ischemia/reperfusion injury. The number of TUNEL positive cells in the ropivacaine group was significantly lower than those values of the control group in the frontoparietal cortex at 3 days after injury, but the caspase-3 activity was higher in the ropivacaine group than that in the control group at 1 day after injury. Conclusions: The study data indicated that a superior cervical sympathetic ganglion block may reduce the neuronal injury caused by focal cerebral ischemia/reperfusion, but it may not prevent the delayed damage.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.6
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• pp.1487-1494
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• 2008

This study was conducted to determine the effect of Gagamjeongji-hwan (JJH)(Jiajiandingzhi-wan) and Evoidae Fructus (EF) on learning and memory disturbance and neuronal damage induced by focal ischemia in the rat. Rats were used for testing in the following three. Morris Water Maze, Cholineacetyltransferase (ChAT) immunohistochemistry, acetylcholine esterase (AchE) histochemistry. JJH+ISCH group (ischemia-induced rats pretreated with JJH) and EF+ISCH group (ischemia-induced rats pretreated with EF) significantly reduced the latency of swimming time, compared with those of ISCH group (ischemia-induced rats) in morris water maze acquisition test. JJH+ISCH group attenuated ischemia.induced learning and memory damage in morris water maze retention test. The density of ChAT neurons of the JJH+ISCH and EF+ISCH group in the hippocampal CA1 area was increased, compared to that of SAL+ISCH group (ischemia-induced rats pretreated with SAL). The density of AchE neurons of the JJH+ISCH and EF+ISCH group in the hippocampal CA1 and CA3 area was increased, compared to that of SAL+ISCH group. These results suggest that Gagamjeongji-hwan (JJH) and Evodiae Fructus (EF) may have significant protective effects on ischemia-induced brain damage and memory impairments.

• Journal of Oriental Neuropsychiatry
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• v.18 no.1
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• pp.153-171
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• 2007

Objective : The aim of this study was to investigate effects of Gagambosim-Tang(GBT) of focal brain ischemic injury induced by intraluminal filament insertion in the rats. Method : The ischemia was induced by intraluminal filament insertion into middle cerebral artery Eight-arm radial maze was designed for the behavioral task. Gagambosim-Tang was orally administrated in SD rats for 21 days. The task was started on the 4th week after focal brain injury, and performed two trials per day for 6days. The effects of Gagambosim-Tang on neuroprotective agents in cresyl violet, choline acetyltranferase(ChAT), nerve growth factor (NGF)-stain and c-Fos with ischemic injury were investigated. Results : The errors in the eight-arm radial maze task were significantly decreased in normal group compared with control group on 2-6days, GBT lX(42.2 mg/ml)orally administrated group on 1days, GBT 6X(253.2 mg/ml) on 3, 5, 6days. The rate of correct choice was increased in normal and GBT 6X groups. The neuroprotective effect in the hippocampal CA1 was increased in normal and GBT 1X, GBT 6X groups compared with control group. The density of ChAT in the hippocampal CA1 was increased in normal and GBT6X groups compared with control group. The density of NGF in the hippocampal CA1 was increased normal and GBT6X groups compared with control group. The number of c-Fos-positive neurons in the hippocampal CA1 was increased in normal and GBT 6X groups compared with control group. Conclusion : These results suggest that Gagambosim-Tang may have protective effect on dementia.

• Journal of Korean Biological Nursing Science
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• v.3 no.1
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• pp.41-52
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• 2001

This study was undertaken to investigate the effects of n-6(corn oil) & n-3(fish oil) fatty acids on infarction size and the cerebral activities of antioxidant enzyme in rat focal brain ischemia model. Weaning Sprague-Dawley rats were fed with either corn oil supplemented diet(COD, 14% corn oil) or fish oil supplemented diet(FOD, 14% menhaden oil) for 6 weeks. The right middle cerebral artery was occluded for 2 hours with a silicon rubber coated nylon surgical thread. After 24 hours of recirculation, the rats were sacrificed and brain sections were photographed using CCD camera after staining with 2, 3, 5-triphenyltetrazolium chloride for 60 minutes in room temperature. The infarcted area was measured and the volume of infarction was calculated. Catalase(CAT), superoxide dismutase(SOD) activities, and fatty acid composition in the brain were also measured. The total and corrected infarction volumes were not significantly different between FOD and COD group. The docosagexaenoic acid(DHA) and DHA content/arachidonic acid(AA) ratio of the cerebral cortex, an index of defense against lipid oxidation, were significantly increased in FOD group compared to those of COD group(p<0.05). In the left cortex(non-infarction side) as well as the right cortex(infarction side) of FOD group, CAT and Cu/Zn SOD activities were higher than those of the COD group(p<0.05). However, CAT and Cu/Zn SOD activities were not significantly different between the left cortex(non-infarction side) and the right cortex(infarction side) of both FOD and COD group. GPx activities were also not significantly different between two groups. Our results demonstrate that the brain infarction size in FOD and COD were not significantly different. However, cerebral lipid composition and antioxidant enzyme activities in FOD and COD group were different. Fish oil, a source of n-3 polyunsaturated fatty acid(PUFA) and corn oil, that of n-6(PUFA) may have a protective effect against oxidative stress induced via different mechanisms.

• The Korean Journal of Pain
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• v.20 no.2
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• pp.83-91
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• 2007

Background: Cerebral blood vessels are innervated by sympathetic nerves that originate in the superior cervical ganglia (SCG). This study was conducted to determine the effect of an SCG block on brain injury caused by focal cerebral ischemia/reperfusion in a rat model. Methods: Male Sprague-Dawley rats (270-320 g) were randomly assigned to one of three groups (lidocaine, ropivacaine, and control). After brain injury induced by middle cerebral artery (MCA) occlusion/reperfusion, the animals were administered an SCG bloc that consisted of $30{\mu}l$ of 2% lidocaine or 0.75% ropivacaine, with the exception of animals in the control group, which received no treatment. Twenty four hours after brain injury was induced, neurologic scores were assessed and brain samples were collected. The infarct and edema ratios were measured, and DNA fragmented cells were counted in the frontoparietal cortex and the caudoputamen. Results: No significant differences in neurologic scores or edema ratios were observed among the three groups. However, the infarct ratio was significantly lower in the ropivacaine group than in the control group (P < 0.05), and the number of necrotic cells in the caudoputamen of the ropivacaine group was significantly lower than in the control group (P < 0.01). Additionally, the number of necrotic and apoptotic cells in theropivacaine group were significantly lower than inthe control group in both the caudoputamen and the frontoparietal cortex (P < 0.05). Conclusions: Brain injury induced by focal cerebral ischemia/reperfusion was reduced by an SCG block using local anesthetics. This finding suggests that a cervical sympathetic block could be considered as another treatment option for the treatment of cerebral vascular diseases.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10509-10512
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• 2015

Objective: To investigate the differential features of CT images in children with neuroblastomas (N) and ganglioneuroblastomas (G). Materials and Methods: Clinical data of 12 children in group G and 15 in group N undergoing CT examination and definitely diagnosed by pathology were retrospectively analyzed. The focal conditions were observed and compared in the two groups, including location, size, boundaries, morphology, enhanced degree and mode, abdominal vascular involvement, presence or absence of spanning the midline, infiltration of peripheral organs, angiography manifestations in tumors or surroundings, presence or absence of calcification and vascular tumor emboli as well as metastases of distal organs and lymph nodes. Results: In group N, the incidence of tumors in the adrenal area was conspicuously higher than in group G (P<0.05), while that of tumors with regular morphology and clear boundaries was significantly lower than in group G (P<0.01); Angiography manifestation rate and incidences of vascular embedding, lymph node metastasis, infiltration and organic metastasis in group N were all markedly higher than in group G (P<0.05). There was no statistical significance between the two groups in terms of focal size, presence or absence of calcification and spanning the midline, and enhanced degree and mode, as well as vascular tumor emboli (P>0.05). Conclusions: Mostly located in adrenal areas and with vascular embedding as a primary manifestation, the neuroblastoma extremely readily metastases to lymph nodes and other organs as well as infiltrating local tissues, with dilation on angiography frequent in or around the tumors. With vascular displacement as a primary manifestation, ganglioneuroblastoma has a regular morphology and clear boundaries.

• Journal of Trauma and Injury
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• v.20 no.2
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• pp.101-105
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• 2007

Purpose: This study aimed to find any difference in the clinical or the anatomical findings of vertebral artery dissection (VAD) between the trauma and the non-trauma groups. Methods: We retrospectively reviewed the clinical data and radiologic images of VAD patients. We compared data on symptoms, neurologic deficit, National institutes of health stroke scale (NIHSS) at admission, Rankin score (RS) at admission and discharge, and radiological findings including anatomical features, between the trauma and the non-trauma groups. Results: From January 1997 to May 2006, 42 patients were enrolled and 13 patients (31%) had a history of earlier trauma. Focal neurologic deficit (trauma group 11/13 vs. non-trauma group 11/29), cerebral stroke (10/13 vs. 9/29), and extradural lesions of dissection (6/13 vs. 3/28) were more common in the trauma group than non-trauma group (p=0.007, p=0.017, p=0.018, respectively) and NIHSS at admission and discharge were significantly higher (p=0.012, p=0.001, respectively). Dissecting aneurysms were less frequent in the trauma group (2/13 vs. 19/29, p=0.006). Subarachnoid hemorrhage and unfavorable prognostic value (Rankin score at discharge ${\geq}$ 2) showed no differences between the groups (p=0.540, p=0.267, respectively). Conclusion: In VAD patients after trauma, focal neurologic deficit due to ischemic stroke and a steno-occlusive pattern are more frequent than they are in non-trauma patients. The location of dissection was most frequent at the extradural vertebral artery in the trauma group. NIHSS was higher in the trauma groups but the incidence of an unfavorable prognostic value (RS ${\geq}$ 2) was not significantly different between the groups.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.205-209
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• 2009

Objective : This study was conducted to investigate the correlation between the degrees of injury on brain magnetic resonance imaging (MRI) and the time interval to recovery of consciousness in patients with diffuse axonal injury. Methods : From January 2004 to December 2008, 25 patients with diffuse axonal injury were treated at our hospital. We retrospectively investigated the patients' medical records and radiological findings. We divided the patients into three groups according to the grade of MRI finding : grade I, small scattered lesions on the white matter of the cerebral hemisphere; grade II, focal lesions on the corpus callosum; and grade III, additional focal lesions on the brain stem. Result : Seven patients belonged to the grade I group; 10 to the grade II group; and 8 to the grade III group. The mean Glasgow Coma Scale (GCS) score of all patients at the time of admission was 7.28. Recovery of consciousness was observed in 23 of the 25 patients; the remaining two patients never regained consciousness. The time interval to recovery of consciousness (awake status) ranged from 1 day to 125 days (mean 22.1 days) : grade I group patients, within approximately 1 week (mean 3.7 days); grade II group patients, within approximately 2 weeks (mean 12.5 days); and grade III group patients, within approximately 2 months (mean 59.5 days). Conclusion : Our study results suggest a correlation between the mean time interval to recovery of consciousness in patients with diffuse axonal injuries and the degrees of brain injuries seen on MRI. Patients with grade I and II diffuse axonal injuries recovered consciousness within 2 weeks, while patients with grade III injuries required approximately 2 months.