• Journal of Magnetics
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• 제19권2호
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• pp.197-204
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• 2014

A transcranial magnetic stimulation device is a complicated appliance that employs a switching power device designed for discharging and charging a capacitor to more than 1 kV. For a simple transcranial magnetic stimulation device, this study used commercial power and controlled the firing angle using a Triac power device. AC 220V 60 Hz, the power device was used directly on the tanscranial magnetic stimulation device. The power supply device does not require a current limiting resistance in the rectifying device, energy storage capacitor or discharge circuit. To control the output power of the tanscranial magnetic stimulation device, the pulse repetition rate was regulated at 60 Hz. The change trigger of the Triac gate could be varied from $45^{\circ}$ to $135^{\circ}$. The AVR 182 (Zero Cross Detector) Chip and AVR one chip microprocessor could control the gate signal of the Triac precisely. The stimulation frequency of 50 Hz could be implemented when the initial charging voltage Vi was 1,000 V. The amplitude, pulse duration, frequency stimulation, train duration and power consumption was 0.1-2.2T, $250{\sim}300{\mu}s$, 0.1-60 Hz, 1-100 Sec and < 1 kW, respectively. Based on the results of this study, TMS can be an effective method of treating dysfunction and improving function of brain cells in brain damage caused by ischemia.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.1060-1071
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• 2014

Signals of the Electroencephalogram (EEG) can reflect the electrical background activity of the brain generated by the cerebral cortex nerve cells. This has been the mostly utilized signal, which helps in effective analysis of brain functions by supervised learning methods. In this paper, an approach for improving the accuracy of EEG signal classification is presented to detect epileptic seizures. Moreover, Independent Component Analysis (ICA) is incorporated as a preprocessing step and Short Time Fourier Transform (STFT) is used for denoising the signal adequately. Feature extraction of EEG signals is accomplished on the basis of three parameters namely, Standard Deviation, Correlation Dimension and Lyapunov Exponents. The Artificial Neural Network (ANN) is trained by incorporating Levenberg-Marquardt(LM) training algorithm into the backpropagation algorithm that results in high classification accuracy. Experimental results reveal that the methodology will improve the clinical service of the EEG recording and also provide better decision making in epileptic seizure detection than the existing techniques. The proposed EEG signal classification using feed forward Backpropagation Neural Network performs better than to the EEG signal classification using Adaptive Neuro Fuzzy Inference System (ANFIS) classifier in terms of accuracy, sensitivity, and specificity.

• 한국동물위생학회지
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• 제27권4호
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• pp.335-343
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• 2004

Although human rabies deaths are rare, the disease remains a public health problem in Korea. Here we report the outbreaks and surveillance of animal rabies in Gangwon-do. Animal rabies infections were identified in 119 animals from 1993 to 2003. The $78\%$ of all rabid animals were domestic species in Gangwon-do. Wild Korean raccoon dog (N. p. koreensis) continued to be the only reported rabid wildlife species. Outbreaks of rabies infections in Korean raccoon dogs are found in broad geographic regions across the northern Gangwon-do. The principal rabies hosts today are probably wild animals in Gangwon-do. The malaise, cerebral dysfunction, anxiety, confusion, agitation and abnormal behavior of the animals were the important symptoms of the disease. The Encephalitis, infiltration with lymphocytes and polymorphonuclear leukocytes and the inclusion bodies (Negri bodies) in neuronal cells were the specific histopathological signs. The results of indirect fluorescent antibody test (IFA) for animal rabies diagnosis were identical and the technique was useful to diagnose the disease. Preexposure vaccination is recommended for persons in high-risk groups, such as laboratory workers, veterinarians and certain animal handlers.

• Journal of Korean Neurosurgical Society
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• 제38권1호
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• pp.54-60
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• 2005

The clear cell meningioma[CCM] is a rare and recently described as a histologic variant of meningioma. It has been identified and included in new World Health Organization[WHO] classification of the Central Nervous System[CNS] tumors recently. The CCMs are histologically characterized by sheets of spindled to polygonal cells with clear cytoplasm, which is the expression of high glycogen concentration. The CCMs occur in younger patients and usually are located in the spinal canal and posterior fossa. The most interesting aspect of CCM is the high recurrence rate and aggressiveness. Poor outcome has been shown in intracranial and spinal tumor location, but the indicators that predict outcome have not been established. Until now 22 intracranial CCM cases had been reported in English literature and 3 cases in Korean. The authors report two cases of CCM located at cerebral convexity and one at cavernous sinus those were totally removed [Simpson Grade $I{\sim}II$] by subfrontal, frontal and orbitocranial approaches. The clinical, radiological, histopathological, and neurosurgical features of these cases are discussed with the relevant literatures.

• Journal of Korean Neurosurgical Society
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• 제60권1호
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• pp.118-124
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• 2017

Brain abscess commonly occurs secondary to an adjacent infection (mostly in the middle ear or paranasal sinuses) or due to hematogenous spread from a distant infection or trauma. Pulmonary arteriovenous fistulas (AVFs) are abnormal direct communications between the pulmonary artery and vein. We present two cases of brain abscess associated with asymptomatic pulmonary AVF. A 65-year-old woman was admitted with a headache and cognitive impairment that aggravated 10 days prior. An magnetic resonance (MR) imaging revealed a brain abscess with severe edema in the right frontal lobe. We performed a craniotomy and abscess removal. Bacteriological culture proved negative. Her chest computed tomography (CT) showed multiple AVFs. Therapeutic embolization of multiple pulmonary AVFs was performed and antibiotics were administered for 8 weeks. A 45-year-old woman presented with a 7-day history of progressive left hemiparesis. She had no remarkable past medical history or family history. On admission, blood examination showed a white blood cell count of 6290 cells/uL and a high sensitive C-reactive protein of 2.62 mg/L. CT and MR imaging with MR spectroscopy revealed an enhancing lesion involving the right motor and sensory cortex with marked perilesional edema that suggested a brain abscess. A chest CT revealed a pulmonary AVF in the right upper lung. The pulmonary AVF was obliterated with embolization. There needs to consider pulmonary AVF as an etiology of cerebral abscess when routine investigations fail to detect a source.

• Archives of Pharmacal Research
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• 제29권4호
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• pp.265-275
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• 2006

In the developing brain, capillaries are differentiated and matured into the blood-brain barrier (BBB), which is composed of cerebral endothelial cells, astrocyte end-feet, and pericytes. Since the BBB regulates the homeostasis of central nervous system (CNS), the maintenance of the BBB is important for CNS function. The disruption of the BBB may result in many brain disorders including brain tumors. However, the molecular mechanism of BBB formation and maintenance is poorly understood. Here, we summarize recent advances in the role of oxygen tension and growth factors on BBB development and maintenance, and in BBB dysfunction related with brain tumors.

• 화훼연구
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• 제17권4호
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• pp.242-245
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• 2009

중금속의 하나인 $Cr0_3$의 세포독성과 이에 대한 연꽃(Nelumbo nucifera GAERTN(NNG))의 수술에서 채취한 연꽃추출물의 방어효과를 배양 대뇌신경교세포(C6 glioma cell)를 대상으로 항산화 측면에서 조사하였다. $Cr0_3$의 세포독성을 조사하기 위하여 배양된 C6 glioma 세포를 $4{\sim}55{\mu}M$ 농도의 $Cr0_3$로 48시간동안 처리하였다. XTT 분석법에 의하여 세포생존율을 조사하였다. 그 결과 $Cr0_3$는 처리 농도에 비례하여 C6 glioma세포의 생존율을 유의하게 감소시켰으며 $Cr0_3$의 $55{\mu}M$ 농도 처리에서는 $XTT_{50}$ 값이, $10{\mu}M$에서는$XTT_{90}$ 값이 나타났다. 따라서 세포독성판정기준에 의하여 $Cr0_3$는 C6 glioma세포에 고독성인 것으로 나타났다. 한편, $Cr0_3$의 세포독성에 대한 연꽃추출물의 방어효과를 항산화 측면에서 조사하기 위하여 먼저 연꽃추출물의 항산화활성을 SOD-유사활성에 의하여 조사하였다. 그 결과 $130{\sim}150{\mu}g{\cdot}mL^{-1}$의 연꽃추출물 농도에서 SOD-유사활성이 대조군에 비하여 모두 증가하였으며 특히 $150{\mu}g{\cdot}mL^{-1}$의 NNG추출물의 처리에서는 대조군에 비하여 유의하게 증가한 것으로 나타났다(p<0.05). 이는 또한 비교군으로 사용한 $15{\mu}M$, vitamin E의 SOD유사활성과 매우 유사한 활성을 나타냈다. 따라서 연꽃추출물은 SOD 유사활성을 보임으로서 항산화활성을 나타냈다. 한편, $Cr0_3$의 세포독성에 대한 연꽃추출물의 방어효과를 조사하기 위하여 $Cr0_3$의 $XTT_{50}$ 농도인 $55{\mu}M$에서 배양 C6 glioma 세포를 처리하기 전에 연꽃추출물이 $90-120{\mu}g{\cdot}mL^{-1}$ 농도로 각각 포함된 배양액에서 2시간 동안 배양한 후 이에 대한 세포생존율을 조사하였다. 그 결과 연꽃추출물을 처리한 실험군에서는 $Cr0_3$을 처리한 실험군에 비하여 유의한 세포생존율의 증가를 보였다. 본 실험 결과는 연꽃추출물이 $Cr0_3$의 세포독성을 효과적으로 방어하였음을 알 수 있었다. 이상의 실험 결과로부터 $Cr0_3$는 배양 C6 glioma세포에 고독성을 나타냈으며 항산화활성을 가지고 있는 연꽃추출물은 $Cr0_3$에 의한 세포독성을 효과적으로 방어함으로서 $Cr0_3$의 독성이 산화적 손상과 관련이 있음을 알 수 있었다.

• 한국한의학연구원논문집
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• 제5권1호
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• pp.111-117
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• 1999

세포열을 이용한 허혈/재관류 환경에서 청폐사간탕의 세포보호능을 측정하였다. 청폐사간탕 추출물은 허혈/재관류 환경하에서 발생하는 세포 독성으로부터 대표적 수용성 항산화제인 ascorbic acid보다 높은 세포 보호 활성을 나타내었으며, 산화적 손상의 지표로서 사용되는 지질과산화물(TBARS)를 측정한 결과에서도 ASA와 유사한 활성을 나타내었다. 또한, 허혈/재관류 환경하에서 활성이 증가하여 세포에 산화적 손상을 일으키는 활성 산소종을 유발하는 것으로 알려진 xanthine oxidase 활성 측정에서는 청폐사간탕이 ASA보도 높은 xanthine oxidase 활성 억제능을 보였으며, xanthine oxidase 효소 표품을 이용한 활성 억제능 측정에서도 ASA보다 뛰어난 결과를 보였다. 따라서, 청폐사간탕은 허혈/재관류 환경하에서 세포 보호능이 있는 것으로 추측이되며, 이러한 보호능은 항산화 활성과 더불어서 xanthine oxidase 활성 억제능이 공동 작용의 결과로 사료된다.

• 대한한방내과학회지
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• 제22권4호
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• pp.503-512
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• 2001

Objective : This study was carried out to investigate the effects of DDT on the brain damage and hypertension. Methods : We observed the effect of Dodamtang(DDT) extract on KCN-induced coma, focal brain ischemia by MCA occlusion, cytotoxicity and protection of PC12 cells and B103 cells induced by amyloid ${\beta}$ protein(25-35). To prove the effect of DDT as a blood pressure depressant, we measured aldosterone, renin activity, catecholamine, sodium and NO density using the seperated blood plasma. Results : DDT showed a protective effect on cytotoxicity of PC12 cells and B103 cells induced by amyloid ${\beta}$ protein(25-35) in a dose dependent manner and proved the significant abridgement of brain ischemic area and edema induced by MCA occlusion, a critical decrease of neurologic deficitic grade in the fore-limbs. DDT didn't reduce the duration of KCN(1.87mg/kg iv.)-induced coma and prolonged the survival rate in the case of KCN(3.0mg/kg iv.)-induced coma by the ratio of 20%. While DDT increased the value of NO in SHR, it significantly decreased the blood pressure of SHR and the value of aldosterone& epinephrine in SHR. Conclusions : These results suggested that DDT might be usefully applied for treatment of hypertension, cerebral infarction, and brain damage.

• 대한수의학회지
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• 제40권1호
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• pp.1-16
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• 2000

Nowadays, mongolian gerbil is notably utilized for the research of brain and water deprivation because of a congenital incomplete willis circle structure in the brain, audiogenic seizure in low noise, and special cholesterol metabolism without water absorption for a long time. In this study, we are intend to identify the morphological changes of the catecholaminergic neuron of brain according to the time lapse in the condition of long term water deprivation. 55 mongolian gerbil were divided 10 groups(control, 1, 2, 3, 4, 5, 10, 15, 20, 42th day water deprivation group), of which each group include 5 mongolian gerbils and 5 normal mongolian gerbils in control group were also used for brain atlas as a control. The brains were observed by the immunohistochemical stain using the TH, DBH and PMNT antibody. The results were as followings; 1. The nerve fibers of the TH-immunoreactive neuron were observed only in the and corpus striatum of the telencephalon. 2. Intensity of the immunostain of the nerve fiber in the cerebral cortex and corpus striatum was decreased gradually day by day after water deprivation. 3. The TH-immunoreactive nerve cells were observed in the paraventricular and periventricular nucleus of the 3rd ventricular in the hypothalamus of mongolian gerbil but the number of nerve cells were decreased from the first day of the water deprivation to the 10th day and increased until the 20th day, after than redecreased from the 20th day by the continuous water deprivation. The number of nerve fibers in this area were increased in the first day, but decreased from the 2nd day of water deprivation. The shape and density of the dopamine secreting cells in the brain of mongolian gerbil by the immunoreactive stain were changed in the continuous water deprivation. In this results, we can conclude that dopamine concerned in the water metabolism of mongolian gerbil, and mongolian gerbil could be used as an animal model for the research of water deprivation.