• 한국콘텐츠학회논문지
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• 제11권2호
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• pp.341-352
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• 2011

본 연구는 전침자극이 일과성 뇌허혈이 유발된 흰쥐 대뇌피질에서 GFAP으로 표지되는 반응성 별아교세포증에 미치는 효과를 동정하기위해서 시행되었다. 실험동물은 전침자극군과 대조군으로 구분하였고, 다시 각 집단을 1일, 3일, 7일 군으로 나누어 각기 15마리씩 무작위 배분하여 실험에 사용하였다. 전침은 인체의 족삼리, 곡지, 음릉선에 상응하는 부위에 자침하고 2 Hz의 근육수축이 현저히 보일 때까지 고강도 (1mA)를 자극하였으며, 전침은 연속파, 직각파, 0.2 ms duration으로 매일 1회 오전 10~12시에 10 분 씩 총 10 회 시행한 뒤, 뇌의 조직절편을 제작하여 GFAP에 대한 면역조직화학염색을 실시해 다음과 같은 결과를 산출 하였다. GFAP의 발현은 뇌허혈로 인해 손상이 유발된 대뇌피질의 혈관주위 및 대뇌피질에서 현저하게 높은 수준으로 관찰되었다. 실험군에서 면역조직화학적으로 표지된 별아교세포들을 계수한 바, 대조군에 비해 뇌허혈이 유발된 1 일 군에서 전침자극군이 약간 감소하였고, 3 일 후에는 현저히 감소하였으며, 7 일 후에는 그 감소정도가 둔화되는 양상을 나타냈다. 대조군에 비해 전침자극군에서 GFAP으로 표지된 별모양아교세포의 수가 모두 감소한 것은 전침자극에 의해 손상의 정도가 감소하여, 전침자극이 신경가소성을 유발시키고 있다는 것으로 관찰되었다.

• Journal of Korean Neurosurgical Society
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• 제56권1호
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• pp.21-27
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• 2014

Objective : Infectious spinal disease is regarded as an infection by a specific organism that affects the vertebral body, intervertebral disc and adjacent perivertebral soft tissue. Its incidence seems to be increasing as a result of larger proportion of the older patients with chronic debilitating disease, the rise of intravenous drug abuser, and the increase in spinal procedure and surgery. In Korea, studies assessing infectious spinal disease are rare and have not been addressed in recent times. The objectives of this study are to describe the epidemiology of all kind of spinal infectious disease and their clinical and microbiological characteristics as well as to assess the diagnostic methodology and the parameters related to the outcomes. Methods : A retrospective study was performed in all infectious spinal disease cases presenting from January 2005 to April 2010 to three tertiary teaching hospitals within a city of 1.5 million in Korea. Patient demographics, risk factors, clinical features, and outcomes were assessed. Risk factors entailed the presence of diabetes, chronic renal failure, liver cirrhosis, immunosuppressants, remote infection, underlying malignancy and previous spinal surgery or procedure. We comparatively analyzed the results between the groups of pyogenic and tuberculous spinal infection. SPSS version 14 statistical software was used to perform the analyses of the data. The threshold for statistical significance was established at p<0.05. Results : Ninety-two cases fulfilled the inclusion criteria and were reviewed. Overall, patients of tuberculous spinal infection (TSI) and pyogenic spinal infection (PSI) entailed 20 (21.7%) and 72 (78.3%) cases, respectively. A previous spinal surgery or procedure was the most commonly noted risk factor (39.1%), followed by diabetes (15.2%). The occurrence of both pyogenic and tuberculous spondylitis was predominant in the lumbar spine. Discs are more easily invaded in PSI. At initial presentation, white cell blood count and C-reactive protein levels were higher in PSI compared to TSI (p<0.05). Etiological agents were identified in 53.3%, and the most effective method for identification of etiological agents was tissue culture (50.0%). Staphyococcus aureus was the most commonly isolated infective agent associated with pyogenic spondylitis, followed by E. coli. Surgical treatment was performed in 31.5% of pyogenic spondylitis and in 35.0% of tuberculous spondylitis cases. Conclusion : Many previous studies in Korea usually reported that tuberculous spondylitis is the predominant infection. However, in our study, the number of pyogenic infection was 3 times greater than that of tuberculous spinal disease. Etiological agents were identified in a half of all infectious spinal disease. For better outcomes, we should try to identify the causative microorganism before antibiotic therapy and make every effort to improve the result of culture and biopsy.

• 한국구조물진단유지관리공학회 논문집
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• 제16권6호
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• pp.155-162
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• 2012

해수에 노출된 콘크리트 구조물은 시간의 경과에 따라 철근부식이 야기될 수 있으며, 이는 구조적인 성능저하로 진전된다. 1단계 연구에서 도출된 해수전착시스템의 개발을 통하여 2단계 연구에서는 해수전착 코팅된 철근 및 코팅철근을 사용한 RC 콘크리트 부재의 구조적, 내구적 성능이 평가되었다. 내구적 성능평가에서는 반전위 측정이 수행되었는데, 코팅된 철근은 일반철근의 35%수준의 부식속도를 가지고 있었으므로 높은 내부식성을 확보하고 있었다. 구조실험에서는 직접인장시험, 부착력시험, RC 부재를 이용한 휨 및 전단시험이 수행되었다. 인장강도 시험에서는 3.2%, 부착성능에서는 8.8%의 강도 증가가 코팅된 철근에서 평가되었다. RC보에 대한 실험에서는 최대하중 및 파괴형태는 두가지 경우에서 거의 동일하게 평가되었다. 해수전착된 시편은 철근주위에 콘크리트와 비슷한 화합물(수산화마그네슘, 탄산칼슘)이 형성되므로 부착력 및 강도를 일부 증가시키는 것으로 평가되었다. 해수전착철근은 피로, 내충격성, 장기침지실험 등을 통하여 성능이 입증되면 더욱 활발하게 사용될 것으로 사료된다.

• 환경위생공학
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• 제3권1호
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• pp.19-26
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• 1988

활동성이 강한 중학생을 대상으로 남$\cdot$여, 학생에 따른 세균 오염현황을 파악함으로써 중학생의 보건 교육에 관심을 높이고자 하여 1985년 2월 4일부터 2월 15일까지 서울 시내 중학교에 재학중인 학생 29명을 대상으로 양손으로 부터의 세균을 분리하여 다음과 같은 결과를 얻었다. 1. 손에 오염된 평균 세균수는 1학년 남학생 $3.08\times10^4$개 여학생$2.48\times10^4$개, 2학년 남학생 $3.32\times10^4$, 여학생 $1.64\times10^4$개로 2학년 여학생에 있어 특히 적은 수가 나타남을 알 수 있었다. 2. 중학생 손에서 검출된 세균의 속명은 Staphylococcus, Streptococcus, Micrococcus, Bacillus, Neisseria spp., Branhamella, Acinetobacter, Moraxella, Chromobacterim, Alcaligenes, Flavobacterium, Pseudomonas, Actinobacillus, Pasteurella, Vibrio, Enterobacteria와 Plesiomonas로 17속으로 나타났다. 3. 속명이 밝혀진 균주 중 종명까지 밝혀진 것은 Staphylococcus aureus, Staphylococcus epidemidis, Micrococcus varians, Branhamella catarrhalis, Acinetobacter anitratus, Moraxella bovis, Moraxella urethralis, Pseudomonas aeruginosa와 plesiomonas shigelloid로 9종이 밝혀졌다. 4. Genus 중 전체 학생중 나타난 출현 빈도가 가장 높은 것은 Staphylococcus $(96.6\%)$이었고 그 다음 Enterobacterial $(14.4\%)$ Bacillus$(20.7\%)$, Branhamella$(17.2\%)$순으로 나타났다.

• 한국수자원학회논문집
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• 제43권2호
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• pp.139-151
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• 2010

횡월류식 강변저류지를 포함하는 하천수계의 흐름 모의를 위한 준2차원 부정류 계산모형을 수립하였다. 수립된 모형은 횡월류 흐름에 대해서는 수량보존에 관한 연속방정식 및 월류형 수위-유량 관계식을, 하도에 대해서는 1차원 St. Venant 방정식을 각각 지배방정식으로 하여 흐름을 모의하는 폐합형 계산모형이다. 수립된 모형을 현재 계획 중인 군남 홍수조절지부터 한강 합류 지점까지의 임진강 구간에 대하여 적용하였다. 횡월류 위어의 유량계수에 대한 민감도 분석 결과, 최대유량 및 수위의 저감효과는 유량계수에 관계없이 거의 일정한 것으로 나타났다. 수계 하류 측에 위치한 강변저류지일수록 배수영향이 커지므로 첨두 홍수위의 감소효과는 줄어드는 것으로 모의되었다. 강변저류지의 홍수저감 효과는 조도계수에 따라 크게 달라지며 횡월류 위어의 정부표고가 높을수록 조도계수에 따른 홍수조절 효과의 불확실성이 커지는 것을 알 수 있었다. 강변저류지의 설계를 위해서는 조도계수의 적절한 추정과정이 선행되어야 함은 물론이고, 추정된 조도계수의 불확실성을 감안하여 횡월류 위어의 정부표고를 결정하기 위한 방법의 개발이 필요할 것으로 판단된다.

• Restorative Dentistry and Endodontics
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• 제41권1호
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• pp.12-21
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• 2016

Objectives: To evaluate the effects of three acids on the microhardness of set mineral trioxide aggregate (MTA) and root dentin, and cytotoxicity on murine macrophage. Materials and Methods: OrthoMTA (BioMTA) was mixed and packed into the human root dentin blocks of 1.5 mm diameter and 5 mm height. Four groups, each of ten roots, were exposed to 10% citric acid (CA), 5% glycolic acid (GA), 17% ethylenediaminetetraacetic acid (EDTA), and saline for five minutes after setting of the OrthoMTA. Vickers surface microhardness of set MTA and dentin was measured before and after exposure to solutions, and compared between groups using one-way ANOVA with Tukey test. The microhardness value of each group was analyzed using student t test. Acid-treated OrthoMTA and dentin was examined by scanning electron microscope (SEM). Cell viability of tested solutions was assessed using WST-8 assay and murine macrophage. Results: Three test solutions reduced microhardness of dentin. 17% EDTA demonstrated severe dentinal erosion, significantly reduced the dentinal microhardness compared to 10% CA (p = 0.034) or 5% GA (p = 0.006). 10% CA or 5% GA significantly reduced the surface microhardness of set MTA compared to 17% EDTA and saline (p < 0.001). Acid-treated OrthoMTA demonstrated microporous structure with destruction of globular crystal. EDTA exhibited significantly more cellular toxicity than the other acidic solutions at diluted concentrations (0.2, 0.5, 1.0%). Conclusions: Tested acidic solutions reduced microhardness of root dentin. Five minute's application of 10% CA and 5% GA significantly reduced the microhardness of set OrthoMTA with lower cellular cytotoxicity compared to 17% EDTA.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권2호
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• pp.124-130
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• 2007

In the present study, I investigated the effects of N-methyl-D-aspartate (NMDA), arachidonic acid (AA), and Nitric Oxide Synthase Inhibitor (NOSI), alone or in combination, on the proliferation of cultured primary normal human oral keratinocytes (NHOK). The purpose of this study was therefore the preliminary study for the examination of the interaction between these agents and NHOK in order to elucidate the mechanisms by which epithelial growth and regeneration are regulated. NHOK were obtained from gingival tissue of 20 individuals aged 20 to 29, and third passage (P3) cells were used for this study. The DNA synthesis was measured by the BrdU assay. Addition of low concentration of AA ($1{\mu}M$) and high concentration of AA with NMDA group (NMDA+AA $10{\mu}M$) made DNA synthesis rate increase significantly at the early stage. Adding NNA ($10{\mu}M$) affected DNA synthesis rate to increase significantly in 4 hours. At the early stage, DNA synthesis was significantly active in the NOS-I with NMDA groups than in the control and the NMDA-only group, while it didn't become statistically meaningful in 24 hours. AA $1{\mu}M$ and NNA $10{\mu}M$ may induce the proliferation of the NHOK independently and NOS-I may induce the proliferation of the NHOK with NMDA. These reactions might be related to the NMDA receptor in the cell and the change of the intracellular calcium ion concentration.

• 동아시아식생활학회지
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• 제24권6호
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• pp.776-784
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• 2014

Korean dishes, Hansik are characterized by healthful vegetable intake. The purpose of this study was to evaluate the inhibitory effect of commonly consumed vegetables by Koreans on obesity/metabolic disease-related inflammation. Through statistical analysis of the KNHANES database ($1^{st}$ 1998, $5^{th}$ 2010, 2011) and a literature review, we selected vegetables for study. Among the vegetables, main or sub ingredients of Kimchi were excluded. Samples were prepared using only edible portions and freeze-dried. After grinding, samples were extracted with ethanol, evaporated and finally lyophilized. The cytotoxicity of samples was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, at various concentrations that do not affect cell viability. Raw 264.7 macrophages were treated with lipopolysaccharide (LPS) and 11 kinds of samples or positive control (troglitazone) dissolved in dimethyl sulfoxide (DMSO). After 24 hours, nitric oxide (NO), tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$) and monocyte chemoattractant protein-1 (MCP-1) production were determined. Excepts for young pumpkin and bracken, nine samples effectively reduced NO production compared with control treated with LPS and DMSO. NO levels of five samples (bean sprouts, leeks, eggplant, mugwort, and pumpkin) were similar to that of the positive control. These five samples showed significantly decreased TNF-${\alpha}$ or MCP-1 compared to the control group. Our results suggest that consumption of commonly consumed vegetables contributes to partial prevention of obesity and related metabolic syndrome through reduction of NO, TNF-${\alpha}$, and MCP-1 production.

• Molecules and Cells
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• 제24권2호
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• pp.200-209
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• 2007

We generated gene expression data from the tissues of 50 gastric cancer patients, and applied meta-analysis and gene set analysis to this data and three other stomach cancer gene expression data sets to define the gene expression changes in gastric tumors. By meta-analysis we identified genes consistently changed in gastric carcinomas, while gene set analysis revealed consistently changed biological themes. Genes and gene sets involved in digestion, fatty acid metabolism, and ion transport were consistently down-regulated in gastric carcinomas, while those involved in cellular proliferation, cell cycle, and DNA replication were consistently up-regulated. We also found significant differences between the genes and gene sets expressed in diffuse and intestinal type gastric carcinoma. By gene set analysis of cytogenetic bands, we identified many chromosomal regions with possible gross chromosomal changes (amplifications or deletions). Similar analysis of transcription factor binding sites (TFBSs), revealed transcription factors that may have caused the observed gene expression changes in gastric carcinomas, and we confirmed the overexpression of one of these, E2F1, in many gastric carcinomas by tissue array and immunohistochemistry. We have incorporated the results of our meta- and gene set analyses into a web accessible database (http://human-genome.kribb.re.kr/stomach/).

• Journal of Periodontal and Implant Science
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• 제30권4호
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• pp.757-779
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• 2000

The aim of our study is to achieve complete periodontal tissue regeneration by the application of BMP and resorbable membrane. Three beagle dogs aged over one and half years and weighed 14 to 16 kg were used in this study. Mandibular 1st, 2nd premolars were extracted bilaterally. Horizontal furcation defects were induced around 3rd, 4th premolars bilaterally. BMP-4 were applied in the right side with resorbable membranes and only resorbable membranes were applied in the left side respectively. Each animal was sacrificed at 2, 4, and 8weeks, after regenerative surgery. Specimens were prepared with Hematoxylin-Eosin stain and Goldner's modified Masson Trichrome stain for light microscopic evaluation. The results were as follows: 1. At 2 weeks after regenerative surgery, downgrowth of junctional epithelium was observed both in the membraneapplied site and BMP-4-and-membrane-applied site. 2. At 4 weeks after regenerative surgery, resorbable membranes were completely resolved, therefore would not prevent downgrowth of junctional epithelium. New bone formation, new cementum formation and Sharpey's fiber were observed in BMP-4-andmembrane-applied site. 3. At 8 weeks after regenerative surgery, downgrowth of junctional epithelium was observed in the membrane-applied site. But, new cementum formation was observed in the same site. The extensive regeneration of new bone, new cementum and remarkable formation of Shapey's fiber were showed in BMP-4-and-membrane-applied site. 4. Resorbable membranes were resolved via the cell-mediated processes. 5. Periodontal tissue regeneration were better achieved in the BMP-4-andmembrane-applied site than in the membrane-applied site. Within the above results, BMP-4 may have the strong capability to form the new bone and resorbable membrane may be able to prevent the bony ankylosis. However, resolution rate of resorbable membrane may not be enough to protect rapid epithelial downgrowth for ideal periodontal regeneration. In conclusion, I suggest BMP-4 may have the strong possibility to be utilized in the clinical periodontal treat-