• Title/Summary/Keyword: neuronal model

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Cortical Neuronal Loss after Chronic Prenatal Hypoxia : A Comparative Laboratory Study

  • Chung, Yoon Young;Jeon, Yong Hyun;Kim, Seok Won
    • Journal of Korean Neurosurgical Society
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    • v.56 no.6
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    • pp.488-491
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    • 2014
  • Objective : The purpose of this study was to investigate the prenatal hypoxic effect on the fetal brain development. Methods : We used the guinea pig chronic placental insufficiency model to investigate the effect of hypoxia on fetal brain development. We ligated unilateral uterine artery at 30-32 days of gestation (dg : with term defined as -67 dg). At 50 dg, 60 dg, fetuses were sacrificed and assigned to either the growth-restricted (GR) or control (no ligation) group. After fixation, dissection, and sectioning of cerebral tissue from these animals, immunohistochemistry was performed with NeuN antibody, which is a mature neuronal marker in the cerebral cortex. Results : The number of NeuN-immunoreactive (IR) cells in the cerebral cortex did not differ between the GR and control groups at 50 dg. However, the number of NeuN-IR cells was lesser in GR fetuses than in controls at 60 dg (p<0.05). Conclusion : These findings show that chronic prenatal hypoxia affect the number of neuron in the cerebral cortex of guinea pig fetus at 60 dg. The approach used in this study is helpful for extending our understanding of neurogenesis in the cerebral cortex, and the findings may be useful for elucidating the brain injury caused by prenatal hypoxia.

Effects of ${\alpha}$-Asarone against Global Cerebral Ischemia in Rats

  • Kim, Young-Ock;Kwon, Yong-Soo;Lee, Seong-Eun;Lee, Sang-Won;Lee, Hee-Jae
    • Natural Product Sciences
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    • v.15 no.4
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    • pp.198-202
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    • 2009
  • Based on the use of Acorus gramineus SOLAND (AG) for the treatment of stroke in traditional Korean medicine, the present study was carried out to evaluate neuroprotective effects of ${\alpha}$-asarone after transient global cerebral ischemia using rat 4-vessel occlusion (4VO) model in rats. ${\alpha}$-Asarone (5 mg/kg) administered intraperitoneally significantly protected CA1 neurons against 10 min transient forebrain ischemia as demonstrated by measuring the density of neuronal cells stained with Cresyl violet. ${\alpha}$-Asarone significantly reduced hippocampal neuronal cell death by 85.2% where as its isolated single compounds from AG compared with a vehicle-treated group.

Dehydroevodiamine.HCl Improves Stress-Induced Memory Impairments and Depression Like Behavior in Rats

  • Kim, Hee Jin;Shin, Ki Young;Chang, Keun-A;Ahn, Sangzin;Choi, Hee Soon;Kim, Hye-Sun;Suh, Yoo-Hun
    • The Korean Journal of Physiology and Pharmacology
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    • v.18 no.1
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    • pp.55-59
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    • 2014
  • Dehydroevodiamine HCl (DHED) has been reported to prevent memory impairment and neuronal cell loss in a rat model with cognitive disturbance. We investigated the effect of DHED on memory impairment and behavioral abnormality caused by stress. We demonstrated that DHED can improve stress-induced memory impairments and depression-like behaviors by using open-field test, Y-maze test and forced swimming test. DHED treatment significantly recovered the decreases in the levels of neural cell adhesion molecule (NCAM) proteins caused by stress and the decreases in cell viability. Our results suggested that DHED is a potential drug candidate for neuronal death, memory impairment and depression induced by stress.

Effect of Gojineumja(Guzhenyinzi) on Neural Tissue Degeneration In Mouse Model of Alzheimer Disease (고진음자(固眞飮子)가 Alzheimer Disease 병태모델의 신경세포 손상에 미치는 영향)

  • Kim, Hyun-Joo;Jung, In-Chul;Lee, Sang-Ryong
    • Journal of Oriental Neuropsychiatry
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    • v.20 no.2
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    • pp.31-46
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    • 2009
  • Objectives : This experiment was designed to investigate the effect of Gojineumja(Guzhenyinzi, GJEJ) on damaged neural tissue in cultured glial cells and in the mouse brain tissue. Methods : The effects of the GJEJ on activation of astrocytes and caspase 3-positive cell counts in cultured glial cells administered with ${\beta}$-amyloid peptide were investigated. The effects of the GJEJ on levels of glial fibrillary acidic protein(GFAP)-positive reactive astrocyets and caspase 3-positive cells in the hippocampal subfields in the rats administered with scopolamine were investigated. Results : 1. GJEJ reduced levels of activated astrocytes and caspase 3-positive cell counts in cultured glial cells administered with ${\beta}$-amyloid peptide. 2. GJEJ reduced levels of GFAP-positive reactive astrocyets and caspase 3-positive cells in the hippocampal subfields in the rats administered with scopolamine. Conclusions : The present data. suggest that GJEJ may have a protective function of neuronal and non-neuronal cells in damaged neural tissue caused by AD-like stimulations. Further studies on identification of effective molecular components of GJEJ and their interactions with damaged neural cells would be important for understanding molecular mechanism and may be further applicable for the development of therapeutic strategies.

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BIocompatible Reduced Graphene Oxide Multilayers for Neural Interfaces

  • Kim, Seong-Min;Ju, Pil-Jae;An, Guk-Mun;Kim, Byeong-Su;Yun, Myeong-Han
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.278.1-278.1
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    • 2013
  • Among the prerequisites for stable neural interfacing are the long-term stability of electrical performance of and the excellent biocompatibility of conducting materials in implantable neural electrodes. Reduced graphene oxide offers a great potential for a variety of biomedical applications including biosensors and, particularly, neural interfaces due to its superb material properties such as high electrical conductivity, decent optical transparency, facile processibility, and etc. Nonetheless, there have been few systematic studies on the graphene-based neural interfaces in terms of biocompatibility of electrode materials and long term stability in electrical characteristics. In this research, we prepared the primary culture of rat hippocampal neurons directly on reduced graphene oxide films which is chosen as a model electrode material for the neural electrode. We observed that the viability of primary neuronal culture on the present structure is minimally affected by nanoscale graphene flakes below. These results implicate that the multilayer films of reduced graphene oxides can be utilized for the next-generation neural interfaces with decent biocompatibility and outstanding electrical performance.

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Control of FES Cycling Considering Muscle Fatigue (근피로를 고려한 FES 싸이클링의 제어)

  • Kim Chul-seung;Hase Kazunori;Kang Gon;Eom Gwang-moon
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.6 s.171
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    • pp.207-212
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    • 2005
  • The purpose of this work is to develop the FES controller that can cope with the muscle fatigue which is one of the most important problems of current FES (Functional Electrical Stimulation). The feasibility of the proposed FES controller was evaluated by simulation. We used a fitness function to describe the effect of muscle fatigue and recovery process. The FES control system was developed based on the biological neuronal system. Specifically, we used PD (Proportional and Derivative) and GC (Gravity Compensation) control, which was described by the neuronal feedback structure. It was possible to control of multiple joints and muscles by using the phase-based PD and GC control method and the static optimization. As a result, the proposed FES control system could maintain the cycling motion in spite of the muscle fatigue. It is expected that the proposed FES controller will play an important role in the rehabilitation of SCI patient.

Neuroprotective Activity of Boesenbergia rotunda Against Glutamate Induced Oxidative Stress in HT22 Cells (글루타메이트에 의해 산화적 스트레스를 받은 HT22 세포에서 핑거루트의 신경세포 보호활성)

  • Kim, Eun Seo;Ma, Choong Je
    • Korean Journal of Pharmacognosy
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    • v.53 no.2
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    • pp.79-86
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    • 2022
  • Excessive glutamate causes oxidative stress in neuronal cells, which can cause degenerative neurological disorders. We tried to find medicinal plant showed neuroprotective activity by using glutamate-injured HT22 cell as a model system. In this study, we found that Boesenbergia rotunda methanol extract showed neuroprotective activity against glutamate induced neurotoxicity in mouse hippocampal HT22 cells. B. rotunda methanol extract suppressed the formation of reactive oxygen species and decreased intracellular Ca2+concentration. Also, B. rotunda made mitochondrial membrane potential maintain to normal levels. In addition, B. rotunda increased total glutathione amount and activated antioxidative enzyme such as glutathione reductase and glutathione peroxidase compared to glutamate-treated groups. These results suggested that B. rotunda decreased neuronal cell death damaged by high concentrations of glutamate treatment, via antioxidative mechanism and might be one of candidate of development of new drug to treat neurodegenerative disease such as Alzheimer's disease.

The Effect of Treadmill Exercise on Ischemic Neuronal Injury in the Stroke Animal Model: Potentiation of Cerebral Vascular Integrity (중풍 동물 모델에서의 트레드밀 운동이 허혈성 신경손상에 미치는 효과: 뇌혈관 통합성 강화)

  • Kang, Kyoung-Ah;Seong, Ho-Hyun;Jin, Han-Byeol;Park, Jong-Min;Lee, Jong-Min;Jeon, Jae-Yong;Kim, Youn-Jung
    • Journal of Korean Academy of Nursing
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    • v.41 no.2
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    • pp.197-203
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    • 2011
  • Purpose: This study was done to identify whether pre-conditioning exercise has neuroprotective effects against cerebral ischemia, through enhance brain microvascular integrity. Methods: Adult male Sprague-Dawley rats were randomly divided into four groups: 1) Normal (n=10); 2) Exercise (n=10); 3) Middle cerebral artery occlusion (MCAo), n=10); 4) Exercise+MCAo (n= 10). Both exercise groups ran on a treadmill at a speed of 15 m/min, 30 min/day for 4 weeks, then, MCAo was performed for 90 min. Brain infarction was measured by Nissl staining. Examination of the remaining neuronal cell after MCAo, and microvascular protein expression on the motor cortex, showed the expression of Neuronal Nuclei (NeuN), Vascular endothelial growth factor (VEGF) & laminin. Results: After 48 hr of MCAo, the infarct volume was significantly reduced in the Ex+MCAo group ($15.6{\pm}2.7%$) compared to the MCAo group ($44.9{\pm}3.8%$) (p<.05), and many neuronal cells were detected in the Ex+ MCAo group ($70.8{\pm}3.9%$) compared to the MCAo group ($43.4{\pm}5.1%$) (p<.05). The immunoreactivity of laminin, as a marker of microvessels and Vascular endothelial growth factor (VEGF) were intensively increased in the Ex+MCAo group compared to the MCAo group. Conclusion: These findings suggest that the neuroprotective effects of exercise pre-conditioning reduce ischemic brain injury through strengthening the microvascular integrity after cerebral ischemia.

Statistical Tests for Time Course Microarray Experiments

  • Park, Tae-Seong;Lee, Seong-Gon;Choe, Ho-Sik;Lee, Seung-Yeon;Lee, Yong-Seong
    • Proceedings of the Korean Statistical Society Conference
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    • 2002.05a
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    • pp.85-90
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    • 2002
  • Microarray technology allows the monitoring of expression levels for thousands of genes simultaneously. In time-course experiments in which gene expression is monitored over time we are interested in testing gene expression profiles for different experimental groups. We propose a statistical test based on the ANOVA model to identify genes that have different gene expression profiles among experimental groups in time-course experiments. Using this test, we can detect genes that have different gene expression profiles among experimental groups. The proposed model is illustrated using cDNA microarrays of 3,840 genes obtained in an experiment to search for changes in gene expression profiles during neuronal differentiation of cortical stem cells.

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신경경로의 정보처리에 대한 전기적 특성 연구

  • 박상희;이명호
    • 전기의세계
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    • v.28 no.8
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    • pp.66-71
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    • 1979
  • This paper describes electrical analysis of the information processing of the nervous system. A general-purpose electrical neuronal model for simulating the electrical activity in a single nerve cell and in small groups of nerve cell has constructed. This model consists of two basic electronic modules to represent respectively a "cell body" and an "axon (with synapses)", together with various related appurtenances. The primary advantages of this method are; holistic view, actual physical representation of various electrical activities in a single nerve cell, display of the activity of all nerve cells flexibility with respect to network parameters. Moreover, this model can effectively help push forward our general ability to explore and conceptualize the electrical activity of interconnected networks of nerve cell behaving in concert. Also, this electronic module technique is the best of various means for this task of realistic representation of aggregates of neurons.gregates of neurons.

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