• The KIPS Transactions:PartB
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• v.16B no.3
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• pp.195-202
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• 2009

In this paper, we propose the regions segmentation method of the white matter and the gray matter for brain MR image by using the ant colony optimization algorithm. Ant Colony Optimization (ACO) is a new meta heuristics algorithm to solve hard combinatorial optimization problem. This algorithm finds the expected pixel for image as the real ant finds the food from nest to food source. Then ants deposit pheromone on the pixels, and the pheromone will affect the motion of next ants. At each iteration step, ants will change their positions in the image according to the transition rule. Finally, we can obtain the segmentation results through analyzing the pheromone distribution in the image. We compared the proposed method with other threshold methods, viz. the Otsu' method, the genetic algorithm, the fuzzy method, and the original ant colony optimization algorithm. From comparison results, the proposed method is more exact than other threshold methods for the segmentation of specific region structures in MR brain image.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.1
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• pp.47-57
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• 2022

Stiripentol is an anti-epileptic drug for the treating of refractory status epilepticus. It has been reported that stiripentol can attenuate seizure severity and reduce seizure-induced neuronal damage in animal models of epilepsy. The objective of the present study was to investigate effects of post-treatment with stiripentol on cognitive deficit and neuronal damage in the cornu ammonis 1 (CA1) region of the hippocampus proper following transient ischemia in the forebrain of gerbils. To evaluate ischemia-induced cognitive impairments, passive avoidance test and 8-arm radial maze test were performed. It was found that post-treatment with stiripentol at 20 mg/kg, but not 10 or 15 mg/kg, reduced ischemia-induced memory impairment. Transient ischemia-induced neuronal death in the CA1 region was also significantly attenuated only by 20 mg/kg stiripentol treatment after transient ischemia. In addition, 20 mg/kg stiripentol treatment significantly decreased ischemia-induced astrocyte damage and immunoglobulin G leakage. In brief, stiripentol treatment after transient ischemia ameliorated transient ischemia-induced cognitive impairment in gerbils, showing that pyramidal neurons were protected and astrocyte damage and blood brain barrier leakage were significantly attenuated in the hippocampus. Results of this study suggest stiripentol can be developed as a candidate of therapeutic drug for ischemic stroke.

• Journal of Korean Neurosurgical Society
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• v.29 no.9
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• pp.1233-1237
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• 2000

Objectives : In order to evaluate the metabolic changes associated with pericontusional edematous area in mild head injury, proton magnetic resonance spectroscopy(1H-MRS) was performed in mild head injury patients (initial GCS score 13-15) with focal brain contusion. Methods : Seven head injury patients with initial GCS 13-15(3 males and 4 females : age range 15-65 years, mean age 33 years) have underwent 1H-MRS evaluations. The patients were examined within 7 days after injury(n=7) and 2 months after injury(n=5). The region of interest(ROI) was selected in the edematous area adjacent to traumatic brain contusion upon T2-weighted MR images and a corresponding region of the contralateral hemisphere (ROC, region of contralateral corresponding hemisphere) was examined as well. The metabolic ratios of NAA/Cr and lactate/Cr were compared between ROIs, ROCs and control values. Results : In initial NAA/Cr ratios, the values of ROIs were significantly lower than those of the controls(p=0.009), but there was no difference either between ROIs and ROCs(p=0.410) or between ROCs of patients and the control (p=0.199). In lactate/Cr ratios, the ROIs in all seven patients and the ROCs in two showed increased lactate signals. The lactate/Cr ratios of the ROIs were significantly elevated as compared to those of the ROCs(p=0.02) and the control(p=0.015). In two months follow-up, lactate signals were absent or significantly reduced(p=0.015). In no patients, clinical or radiological deterioration has been observed. Conclusion : Our 1H-MRS results demonstrate that there are significant ischemic changes in pericontusional edematous areas as indicated by elevated lactate signals in the patients with mild head injury. But there were no consistent neural loss or dysfunction in these area. There findings suggest that pericontusional edematous areas can be vulnerable to secondary brain insults even in the patients with mild head injury.

• Journal of Korean Neurosurgical Society
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• v.53 no.6
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• pp.337-341
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• 2013

Objective : After spinal cord injury (SCI), functional and structural reorganization occurs at multiple levels of brain including motor cortex. However, the underlying mechanism still remains unclear. The current study was performed to investigate the alterations in the expression of the main regulators of neuronal development, survival and death, in the brain following thoracic contusive SCI in a mouse model. Methods : Eight-week-old female imprinting control region mice (n=60; 30-35 g) were used in this study. We analyzed the expression levels of regulators such as brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF) and histone deacetylase (HDAC) 1 in the brain following thoracic contusive SCI. Results : The expression of BDNF levels were elevated significantly compared with control group at 2 weeks after injury (p<0.05). The expression of NGF levels were elevated at 2, 4 weeks compared with control group, but these difference were not significant (p>0.05). The GDNF levels were elevated at 2 week compared with control group, but these differences were not significant (p>0.05). The difference of HDAC1 levels were not significant at 2, 4 and 8 weeks compared with control group (p>0.05). Conclusion : These results demonstrate that the upregulation of BDNF may play on important role in brain reorganization after SCI.

• Investigative Magnetic Resonance Imaging
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• v.2 no.1
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• pp.104-112
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• 1998

Purpose : To evaluate the clinical utility of diffusion-weighted imaging by analyzing the signal intersity of lesions in patients with various intracranial diseases. Materials and Methods : difusion-weighted MR imaging was prospectively perormed in randomly selected 70 patients with various intracranial idseases. They consisted of 20 patients with acute infarct, 21 patients with chronic infarct of small vessel disease, 14 patients with primary intracranial tumor, three patients with brain metastasis, five patient with brain abscess, five patients with brain abscess, five patients with cerebral hemorrhage, one patient with neurocysticercosis, and one patient with epidermoid cyst. the diffusion-weighted images were obtained immediately after routine T2-weighted imaging on a 1.5T MR unit using single shot spin echo EPI technique with 6500 ms TR, 107ms TE, $128{\times}128$ matrix, 1 number of excitation, $24{\times}24$ field of view, 5-7 mm slice thickness, 2-3 mm inter-slice gap. The diffusion-gradients (b value of ($1000s{\;}/{\;}textrm{mm}^2$)) were applied along three directions(x, y, z). On visual inspection of diffusion-weighted images, the signal intersity of lesions was arbitrarily graded as one of 5 grades. In quantitative assessment, we measured the signal intensity of all the lesions and the contralateral corresponding normal area using round region of interest(ROI), and then calculated the signal intensity ratio of the lesion to the normal brain parenchyma. Results : On visual inspection, markedly hyperintense signals were seen in all cases of acute infarct, brain abscess, epidermoid cyst, and neurocysticercosis in degenerating stage. In all cases of cerebral hematoma, the very high signal internsity was intermingled with low signal intensity. focal very high signal intersity was also seen in a solid portion of the tumor in a patient. the mean signal intensity ratios of all those lesions to the normal brain parenchyma were above 2.5. Gliosis, solid component of brain tumor, brain metastasis, and vasogenic dedma appeared isointense to the normal brain parenchyma in 71%, 64%, 100%, and 67%, respectively ; the mean signal intensity ratios of those lesions to the normal brain parenchyma ranged 1.15 to 1.28 and there was no significant difference among these(p>0.1). Cystic cerebromalacia and necrotic or cystic portions in tumor were markedly or slightly hypointense, and the mean signal intensity ratios were 0.45 and 0.42, respectively. Conclusion : Very high signal intensity of acute infarct, brain abscess, epidermoid cyst, and cystic neurocysticercosis in degenerating stage on diffusion-weighted images may be helpful in differentiating from other diseases that are hypointense or isointense to the normal brain parenchyma. It may be especially useful differentiation of brain abscess from brain tumor with necrotic or cystic portion.

• Journal of Photoscience
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• v.9 no.2
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• pp.37-40
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• 2002

Ascidians are lower chordates, and their tadpole-like larvae share a basic body plan with vertebrates. To study photoreceptive systems in ascidians, we have isolated and characterized cDNA clones for three opsins, five G protein ${\alpha}$ subunits (G${\alpha}$), catalytic and regulatory subunits of cGMP phosphodiesterase (PDE), and arrestin from the ascidian Ciona intestinalis tadpole larva. Ci-opsin1 and Ci-opsin2 are vertebrate-type opsins, while Ci-opsin3 is a retinal photoisomerase similar to retinochrome and mammalian RGR. Both Ci-opsin1 and arrestin are specifically localized in the photoreceptor cells of the ocellus, whereas Ci -opsin2 is not expressed in the photoreceptors, but is co-localized in another population of neurons in the brain with PDE (Ci-PDE9 and Ci-PDE$\delta$). Ci-opsin3 is present in the entire region of the brain. Though five different cDNAs encoding Ga have been cloned, no transducin-type G protein has been found yet. Interestingly, one of G${\alpha}$i isoform is conspicuously expressed in the entire region of the brain. The Ci-opsin3 gene expression was observed in a broad area of the brain vesicle as well as in the visceral ganglion. Genes encoding ascidian homologs of CRALBP and ${\beta}$-CD, whose function is required for the mammalian visual cycle, are co-expressed with Ci-opsin3 in the brain vesicle and visceral ganglion. Localization of Ci-opsin3, CRALBP, and ${\beta}$-CD in a broad area of the brain suggests that the brain of the ascidian larva has a visual cycle system similar to that of the vertebrate RPE. Based on these data, we discuss the evolution of vertebrate visual systems.

• Journal of The Korean Association For Science Education
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• v.30 no.5
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• pp.647-667
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• 2010

The purpose of this study was to develop a brain-based analysis framework for evaluating teachinglearning program in science. To develop the framework, this study categorized educational constructs of the teachinglearning programs into one of three teaching-learning factors: cognition, motive, and emotion, using previous studies on science program. Ninety-three articles on the brain functions associated with science program were analyzed to extract brain activation regions related to the three educational constructs. After delineating the brain activation regions, we designed the brain function map, "the CORE Brain Map." Based on this brain map, we developed a brain-based analysis framework for evaluating science teaching-learning program using R & D processes. This framework consists of the brain regions, the bilateral dorsolateral prefrontal cortex, the bilateral ventrolateral prefrontal cortex, the bilateral orbitofrontal cortex, the anterior cingulate gyrus, the bilateral parietal cortex, the bilateral temporal cortex, the bilateral occipital cortex, the bilateral hippocampus, the bilateral amygdala, the bilateral nucleus accumbens, the bilateral striatum and the midbrain regions. These brain regions are associated with the aforementioned three educational factors; cognition, motivation, and emotion. The framework could be applied to the analysis and diagnosis of various teaching and learning programs in science.

• The Journal of Korean Physical Therapy
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• v.14 no.1
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• pp.125-130
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• 2002

This study was applied using vojta therapy in the patient with hydrocephalus occurred by on traumatic brain injury. Vojta treatment was a recently developed of the brain damage patient treatment which can be applied eariler than the other traditional methods. The results were as follows. 1. Hip joint flexion contracture from $100^{\circ}$ to $15^{\circ}$ was improved on prone position. 2. Left convexity curve on thracolumbar region due to functional scoliosis the normal aligment. 3. The thumb finger was changed from thumb-in to thumb-out. 4. Right tilted pelvis on prone position became the normal symmetry

• BMB Reports
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• v.30 no.1
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• pp.33-36
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• 1997

Age-dependent deletion of mitochondrial DNA (mtDNA) was detected in mouse brain using PCR method. The size of the deleted fragment was 0.5 kb, 0.9 kb. 1.7 kb and 4.3 kb in the region between cytochrome b gene and ATPase 6 gene. The deleted fragment was increased gradually from 3-month to 22month Direct repeat sequence flanking the deletion in 0.5 kb PCR product was TAAT.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2000.04a
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• pp.15-16
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• 2000

Transient forebrain ischemia results in delayed neuronal death in the CA1 region of the hippocampus after injury, which is, at least in part, a consequence of excessive generation of reactive oxygen species. Previous in vitro studies using cell cultures or brain slices have demonstrated that phospholipase D (PLD) in the nervous system is involved in the signaling mechanism in response to a variety of agonists. Several recent studies have shown that reactive oxygen species stimulate phospholipase D (PLD) activity in several kinds of cells. Therefore, this raises the possibility that PLD activity is enhanced in the ischemic brain. Meanwhile, osteopontin (OPN) was initially identified as a sialoglycoprotein in bone, but has since been found in various tissues. Although not much is known about its function, OPN seems to play an important role in inflammation and tissue repair. Recently, it was reported that OPN was upregulated in the activated microglia after focal brain ischemia, suggesting that OPN might play a role in wound healing after a focal stroke.