• 한국분말재료학회지
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• 제27권2호
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• pp.119-125
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• 2020

One of the promising candidates for accident-tolerant fuel (ATF), a ceramic microcell fuel, which can be distinguished by an unusual cell-like microstructure (UO₂ grain cell surrounded by a doped oxide cell wall), is being developed. This study deals with the microstructural observation of the constituent phases and the wetting behaviors of the cell wall materials in three kinds of ceramic microcell UO₂ pellets: Si-Ti-O (STO), Si-Cr-O (SCO), and Al-Si-Ti-O (ASTO). The chemical and physical states of the cell wall materials are estimated by HSC Chemistry and confirmed by experiment to be mixtures of Si-O and Ti-O for the STO; Si-O and Cr-O for SCO; and Si-O, Ti-O, and Al-Si-O for the ASTO. From their morphology at triple junctions, UO₂ grains appear to be wet by the Si-O or Al-Si-O rather than other oxides, providing a benefit on the capture-ability of the ceramic microcell cell wall. The wetting behavior can be explained by the relationships between the interface energy and the contact angle.

• Journal of Nutrition and Health
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• 제56권1호
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• pp.12-23
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• 2023

Purpose: This study investigates the alterations in A549 human non-small-cell lung cancer (NSCLC) cells exposed to Citrus junos extract (CJE). We further examine the antiproliferative and apoptotic effects of CJE on NSCLC cells. Methods: Inhibition of proliferation was examined by applying the 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) colorimetric assay on CJE-treated A549 NSCLC cells. The lactate dehydrogenase (LDH) assay was performed to measure the degree of toxicity of CJE on NSCLC cells. The effect on migratory proliferation was confirmed using the scratch wound healing assay. The antiproliferative effect of the CJE on human lung cancer cells was verified through morphological observation, fluorescence microscopy, and caspase-3 colorimetry. Results: Exposure of NSCLC cells to CJE resulted in a dose- and time-dependent decrease in cell activity and increased toxicity to the cells. In addition, microscopic observation revealed a reduced ability of the cancer cells to migrate and proliferate after exposure to the CJE, with simultaneous morphological apoptotic changes. Fluorescence staining and microscopic examination revealed that this death was a process of self-programmed cell death of NSCLC cells. Compared to unexposed NSCLC cells, the expression of caspase-3 was significantly increased in cells exposed to CJE. Conclusion: Exposure of A549 human NSCLC cells to CJE inhibits the proliferation, increases the cytotoxicity, and decreases the ability of cells to migrate and grow. Moreover, the expression of caspase-3 increases after CJE treatment, suggesting that the apoptosis of NSCLC cells is induced by a chain reaction initiated by caspase-3. These results indicate that Citrus junos is a potential therapeutic agent for human non-small-cell lung cancer.

• 대한약침학회지
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• 제1권1호
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• pp.22-34
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• 1997

In order to investigate experimentally that effect of Moschus, Bovis Calculus, Ursi Fel aqua-acupuncture on acutely damaged liver of rats induced by radix aconiti, the author gave Moschus, Bovis Calculus, Ursi Fel aqua-acupuncture according to method of manufacture stimulation to corresponding points, Kan-su (B18) and Ki-mun (Liv14), and carried out hematological, serological examination and electromicroscopical observation. The following results were obstained : 1. At 6 hours, cell organelles induced by radix aconiti toxicity prominently destructed in control and aqua-acupuncture treatment groups. 2. At 12 hours, cell organelles, destruction was some similarities between control group and aqua-acupuncture treatment group. 3. At 24 hours, rough endoplasmic reticulum and Golgi complex comparatively developed in aqua-acupuncture group treatment as compared with control group. 4. At 48 hours, cell organelles, destruction was recovered in aqua-acupuncture treatment group as compared with the control group and it was similiar normal findings. According to the above findings, it is considered that Moschus, Bovis Calculus, Ursi Fel aqua-acupuncture has effects of recovery of acutely damaged liver.

• Journal of Microbiology and Biotechnology
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• 제6권6호
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• pp.468-473
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• 1996

The genome of tomato spotted wilt virus (TSWV) is composed of three RNA segments, S, M, and L RNA and the 5.0 kb M RNA encodes two glycoproteins Gl, G2 and NSm protein of unknown function. In an effort to investigate the function of the NSm protein, antibody was raised against NSm fusion protein overexpressed in Escherichia coli. This antibody was used to detect the NSm protein by using western blot analysis and electron microscopic observation after immunogold labelling. For the cloning of the NSm gene, total RNA extracted from a TSWV infected plant was used for cDNA synthesis and polymerase chain reaction (PCR) instead of going through time-consuming virus purification. A protein band specifically reacting to the NSm antibody was detected from TSWV inoculated plants. The NSm protein was detected in the cell wall fraction and in pellet from low speed centrifugation when the infected plant tissue was fractionated into 4 fractions. In the immuno-electron microscopic observation, gold particles were found around the plasmodesmata of infected plant tissue. These results suggest that the NSm protein of TSWV plays some role in cell-to-cell movement of this virus.

• 한국동물위생학회지
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• 제19권1호
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• pp.1-29
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• 1996

This study was conducted to elucidate the pathogenesis of Aujeszky's disease virus(ADV) by histopathologic examination. The first Korean ADV Isolate, which was isolated from piglets with clinical signs of Aujeszky's disease in Yangsan(YS) county, Kyungnam province, was inoculated into 32 days old piglets with a dose of $10^{5.9}$$TCID_{50}/ml$ through intranasal or intramuscular route. These piglets were sacrificed at intervals of every 24hrs for 8 days. The virulence of YS strain was determined by the observation of clinical signs, gross findings, and histopathologic changes in tissues. The virus recovery test was performed from brain, spleen, lung and tonsil in cell culture. The pathogenesis of YS strain was determined by the observation of histopathologlc lesions in CNS and neuronal tracts. The major clinical signs were fever, anorexia, dyspnea, constipation, tremor, ataxia, circling movement, hindleg paralysis and salivation. The clinical signs were more severe in piglets of the group inoculated intranasally than those of the intramuscularly inoculated gorup. Lymphocytopenia was detected on day 5 to day 6 postinoculation (PI). The ADV was recovered from the tissue homogenates of tonsil, lung, spleen and cerebrum in cell culture. The highest virus titer was detected from tonsil between day 6 and day 7 PI. Reddish sublobar consolidation foci were scattered in the apical and cardiac lobes of lung. Although yellowish necrotic foci were detected in tonsil and liver, hemorrhagic lesions were mainly observed in heart, kidney and lymph nodes. Histopathologically, degeneration and necrosis of nerve cells, nonsuppurative meningoe-ncephalitis, nodular gliosis and perivascular cuffings were observed in CNS. Multifocal fibronecrotic foci were observed in lung, liver, lymph nodes and spleen. The major pathologic changes were detected in the midbrain, pons and medulla oblongata. Eosinophilic intranuclear inclusion bodies were mainly observed in epithelia and /or macrophages of tonsil, liver, lung, spleen and submandibular lymph nodes, and neurons of brain, respectively. Observation of viral particles at various stages of replication were possible from the endothelial cells of the alveolar capillaries and tonsillar crypt epithelia by transmission electron microscope.

• 한국산학기술학회논문지
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• 제12권9호
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• pp.4038-4045
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• 2011

본 논문은 백지 에탄올추출물의 미백효능을 조사하기 위하여 melan-a cell, 브라운 기니피그 및 HMB-45 염색을 사용하였다. melan-a 세포에 시료를 6.25, 12.5, 25, 50, ${\mu}g/m{\ell}$ 농도로 처치하여 세포 생장율의 변화 관찰 및 멜라닌세포의 형태학적 변화를 관찰하였다. 또한 brown guinea pig (450~500 g)등 부위에 1500 mJ/$cm^2$ 광량의 ultraviolet B조사로 유발시킨 인공색소반 (${\Phi}$ 2 mm)에 1일 2회, 주 5일, 매회 30 ${\mu}{\ell}$씩 총 5주간 시료를 도포하여 주 1회 육안적 변화를 관찰 하였고, 실험 5주째 되는 날 실험동물은 염산 케타민으로 마취 후 시료를 도포한 인공색소반 부위를 biopsy punch로 절취하여 HMB-45 염색으로 멜라닌소체 내 glycoprotein(gp100) 단백질의 조직학적 변화를 관찰 하였다. 세포생장율 측정에서 시료처치 6.25~50 ${\mu}g/m{\ell}$에서의 세포생장율은 높았고, 멜라닌세포의 형태학적 변화에서는 시료처치 농도가 증가할수록 멜라닌합성 및 수지상 돌기가 적게 관찰 되었다. 동물 실험 육안적 관찰에서 시료 도포군이 용매대조군에 비해 멜라닌 색소침착 정도가 확연하게 밝아졌고, gp100 단백질의 조직학적 관찰에서 시료 도포군은 gp100 단백질 발현 정도가 현저하게 줄어들었으며, 영상분석에서도 시료 도포군이 용매대조군에 비해 유의하게(p<0.001) 감소하였는데 이러한 결과는 현미경 관찰 결과와 일치하였다. 이상의 결과를 종합하면 백지 에탄올추출물은 우수한 미백효과가 있는 것으로 판단된다.

• 대한기계학회논문집A
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• 제33권1호
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• pp.56-63
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• 2009

Cell migration is one of the essential mechanisms responsible for complex biological processes. Intensive researches have begun to elucidate the mechanisms and search intriguing conditions for efficient control of cell migration. One general mechanism that is widely applicable for cells including Escherichia coli, amoebae and endothelial cell is chemotaxis. The single cell study for bacterial chemotaxis has an advantage over studies with the population of cells in providing a clearer observation of cell migration, which leads to more accurate assessments of chemotaxis. In this paper, we propose a three-dimensional model considering a single bacterium to study its chemotaxis. The semi-implicit Fourier spectral method is applied for high efficiency and numerical stability. The simulation results reveal rich dynamics of cell migration and provide quantitative assessments of bacterial chemotaxis with various chemoattractant gradient fields.

• 한국과학교육학회지
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• 제36권4호
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• pp.617-628
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• 2016

과학교육현장에서 이루어지는 과학적 실천(practice) 과정에는 다양한 암묵적 지식이 존재한다. 교사는 이 암묵적 지식을 학생들에게 지도하는데 있어 자신의 과학에 대한 가치지향점을 반영할 가능성이 높다. 따라서 이 연구에서는 현미경 세포 관찰 실험 상황에서 관찰 및 이미지 재현이라는 과학적 실천의 지도 과정에서 나타나는 예비교사들의 가치지향점을 확인해보고자 한다. 특히 이 연구에서는 과학적 관찰행동의 가장 큰 지향점인 객관성을 중심으로 예비교사들의 인식을 확인해보고자 한다. 이를 위하여 예비교사 50명에게 현미경 세포 관찰 실험에서 일어날 수 있는 상황에 대하여 자신의 생각을 서술하게 하였고, 서술한 자료들은 과학교육 전문가 2인의 반복적 비교분석을 통해 귀납적으로 범주화되었다. 그 결과 존재의 확인을 위한 수단으로서 관찰을 인식하는 '존재 확인 지향', 관찰은 객관적으로 이루어져야 한다는 '기계적 객관성 지향', 관찰의 주관적 성격을 인정하는 '학생의 주관성 지향', 관찰 대상과 표본 제작 및 관찰 과정에서 나타나는 인공적 산물을 구별하는 능력을 중시하는 '훈련된 판단 지향'의 4가지 유형을 확인할 수 있었다. 이 중 '기계적 객관성 지향' 유형이 예비 생물교사들에게 가장 많이 나타나 객관성이 관찰과 이미지 재현 행위에 대해 중요한 신념으로 작용함을 알 수 있었다. 또한 하나의 실험과 그 실험에 매개된 암묵적 지식에 대한 지도 과정에서 예비교사들의 다양한 가치지향점이 반영될 수 있음을 확인할 수 있었다. 교사들의 과학적 실천에 대한 이러한 가치지향점은 학생들의 지도행위와 평가에 직접적 영향을 미친다는 점에서 앞으로 교사교육에 많은 시사점을 줄 수 있을 것이다.

• 한국식품영양과학회지
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• 제22권4호
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• pp.494-499
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• 1993

렉틴투여 마우스의 소장을 고정절편으로 해서, HE 염색한 후 광학현미경관찰 및 조직을 반전고정해서 주사형전자현미경관찰을 하여, 소장점막의 미융모막의 변화를 대조군과 비교했다. 그 결과 소장융모의 팽윤, 단평화, 소장벽의 박약화, 상피세포의 밀도화 및 흐트러짐 등이 관찰되었다. 즉 렉틴이 정상적인 생체기능을 방해한다는 의미에서의 독활성이 있다는 것은, 소장조직에의 영양소흡수부전이 하나의 요인이 됨을 알 수 있다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권2호
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• pp.92-98
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• 2000

Mesangial cell has several key roles in thee control of glomerular function: it partocipates in the regulation of glomerular filtration rate, macromolecular clearance, and as both a source and target of numerous hormones and autocrines. Many of these insights into mesangial cell function have been obtained by studying mesangial cells in culture. However, no suitble cell lines have established yet. We here reported the immortalization of rat kidney glomeruar mesangial cell by transfection of E6 and E7 genes of human papillomavirus type 16 (HPV-16) via electroporation and lipofection. The reslts showed that only electroporation could transfect the genes to mesangial cells and the transfected cells maintained the viability for longer than 6 months. Fluorescence microscopic observation showed that cellular contractility and phagocytosis, which are the two main phenotypes of mesangial cells with rat glomerular epithelial cells showed that the growth of mesangial dells was suppressed by epithelial cell, but the growth of epithelisl cells was enhanced by mesangial cells. Moreover, Such results may imply that the glomerular cell-cell interaction plays an important role in the regulation of cell proliferation and differentiation.