• Journal of Periodontal and Implant Science
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• 제35권2호
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• pp.335-343
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• 2005

Inorganic bovine bone mineral has been widely researched as bone substitution materials in orthopedic and oral and maxillofacial application. OCS-B(NIBEC, Korea) is newly-developed inorganic bovine bone mineral. The aim of this study is to evaluate the safety and efficacy of bovine bone-derived bone graft material(OCS-B). Micro-structure of newly-developed inorganic bovine bone mineral(OCS-B) was analyzed by scanning electron microscope(SEM). Round cranial defects with eight mm diameter were made and filled with OCS-B in rabbits. OCS-B was inserted into femoral quadrant muscle in mouse. In scanning electron microscope, OCS-B was equal to natural hydroxyapatite. Rabbits were sacrificed at 2 weeks and 4 weeks after surgery and mice were sacrificed at 1 week and 2 weeks after surgery. Decalcified specimens were prepared and observed by microscope. In calvarial defects, osteoid and new bone were formed in the neighborhood of OCS-B at 2 weeks after surgery. And at 4 weeks after surgery osteoid and new bone bridge formed flourishingly. No inflammatory cells were seen on the surface of OCS-B at 1 week and 2 weeks in mouse experimental group. It is concluded that newly-developed inorganic bovine bone mineral(OCS-B) is a flourishing bone-forming material and biocompatible material.

• The Journal of Advanced Prosthodontics
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• 제8권1호
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• pp.1-8
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• 2016

PURPOSE. The purpose of this study was to evaluate the efficacy of two different metal conditioners for non-precious metal alloys for the bonding of porcelain to a cobalt-chromium (Co-Cr) alloy. MATERIALS AND METHODS. Disk-shaped specimens ($2.5{\times}10.0mm$) were cast with Co-Cr alloy and used as adherend materials. The bonding surfaces were polished with a 600-grid silicon carbide paper and airborne-particle abraded using $110{\mu}m$ alumina particles. Bonding specimens were fabricated by applying and firing either of the metal conditioners on the airborne-particle abraded surface, followed by firing porcelain into 5 mm in diameter and 3 mm in height. Specimens without metal conditioner were also fabricated. Shear bond strength for each group (n=8) were measured and compared (${\alpha}=.05$). Sectional view of bonding interface was observed by SEM. EDS analysis was performed to determine the chemical elements of metal conditioners and to determine the failure modes after shear test. RESULTS. There were significant differences among three groups, and two metal conditioner-applied groups showed significantly higher values compared to the non-metal conditioner group. The SEM observation of the sectional view at bonding interface revealed loose contact at porcelain-alloy surface for non-metal conditioner group, however, close contact at both alloy-metal conditioner and metal conditioner-porcelain interfaces for both metal conditioner-applied groups. All the specimens showed mixed failures. EDS analysis showed that one metal conditioner was Si-based material, and another was Ti-based material. Si-based metal conditioner showed higher bond strengths compared to the Ti-based metal conditioner, but exhibited more porous failure surface failure. CONCLUSION. Based on the results of this study, it can be stated that the application of metal conditioner is recommended for the bonding of porcelain to cobalt-chromium alloys.

• 폴리머
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• 제33권6호
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• pp.602-607
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• 2009

심혈관용 소재로서 혈관내피전구세포의 포획을 통해 in vivo 내피세포화가 가능한 표면을 가진 폴리우레탄 표면을 개발하였다. 혈관내피전구세포의 점착을 유도하는 CD34 단일클론항체(monoclonal antibody, mAb)를 표면에 도입하기 위해, poly (poly (ethylene glycol) acrylate-co-butyl methacrylate), poly (PEGA-co-BMA) 공중합체가 합성되었고, 이를 폴리우레탄 표면에 코팅하여 CD34 단일클론항체를 화학적으로 고정화하였다. 중합된 공중합체의 $^1H$-NMR 분석은 원하는 조성을 가진 poly(PEGA-co-BMA)의 합성이 가능함을 확인해 주었다. 이전 연구에서 개발된 PEG가 그래프트된 폴리우레탄과의 비교를 통해, 본 연구에서 제조된 poly(PEGA-co-BMA)가 코팅된 폴리우레탄 표면이 CD34 mAb의 고정화에 더 효과적인 것으로 나타났으며, 이는 CD34 mAb의 표면밀도와 활성도가 32배 이상 증가된 결과를 통해 증명되었다. 개질된 폴리우레탄 표면의 물리화학적 특성은 XPS와 물 접촉각, AFM에 의해 분석되었으며, 각각의 개질된 표면에 따른 표면의 특이적 성질을 잘 보여주었다. 본 연구에서 얻어진 결과들은 poly(PEGA-co-BMA)의 코팅을 통해 제조된 표면이 CD34 mAb의 고정화에 효과적임을 설명하였으며, 실제로 심혈관용 소재의 개발에 적용 가능성이 크다는 것을 증명해 주었다.

• Journal of Ginseng Research
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• 제35권2호
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• pp.235-242
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• 2011

To obtain microorganisms for the microbial conversion of ginsenosides in red ginseng extract (RGE), mushroom mycelia were used for the fermentation of RGE. After fermentation, total sugar contents and polyohenol contents of the RGEs fermented with various mushrooms were not a significant increase between RGE and the ferments. But uronic acid content was relatively higher in the fermented RGEs cultured with Lentus edodes (2155.6 ${\mu}g/mL$), Phelllinus linteus (1690.9 ${\mu}g/mL$) and Inonotus obliquus 26137 and 26147 (1549.5 and 1670.7 ${\mu}g/mL$) compared to the RGE (1307.1 ${\mu}g/mL$). The RGEs fermented by Ph. linteus, Cordyceps militaris, and Grifola frondosa showed particularly high levels of total ginsenosides (20018.1, 17501.6, and 16267.0 ${\mu}g/mL$, respectively). The ferments with C. militaris (6974.2 ${\mu}g/mL$), Ph. linteus (9109.2 ${\mu}g/mL$), and G. frondosa (7023.0 ${\mu}g/mL$) also showed high levels of metabolites (sum of compound K, $Rh_1$, $Rg_5$, $Rk_1$, $Rg_3$, and $Rg_2$) compared to RGE (3615.9 ${\mu}g/mL$). Among four different RGE concentrations examined, a 20 brix concentration of RGE was favorable for the fermentation of Ph. linteus. Maximum biotransformation of ginsneoside metabolites (9395.5 ${\mu}g/mL$) was obtained after 5 days fermentation with Ph. linteus. Maximum mycelial growth of 2.6 mg/mL was achieved at 9 days, in which growth was not significantly different during 5 to 9 days fermentation. During fermentation of RGE by Ph. linteus in a 7 L fermenter, $Rg_3$, $Rg_5$, and $Rk_1$ contents showed maximum concentrations after 5 days similar to flask fermentation. These results confirm that fermentation with Ph. linteus is very useful for preparing minor ginsenoside metabolites while being safe for foods.

• 한국식품과학회지
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• 제37권5호
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• pp.702-708
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• 2005

잣의 혈중 콜레스테롤 저하효과를 동물실험을 통하여 확인하기 위하여 기본식이(정상군), 기본식이에 콜레스테롤을 첨가한 식이(대조군), 그리고 기본식이에 콜레스테롤과 여러 농도의 잣을 함유한 실험식이(실험군)를 각 군별로 섭취하게 한 결과 잣의 농도에 따른 식이섭취량과 체중변화량의 유의적인 차이는 크게 나타나지 않았다. 식이효율은 저농도로 잣을 섭취한 경우에는 대조군과 차이를 나타내지 않았지만 10% 이상의 고농도의 잣을 섭취한 경우에는 식이효율이 높았다. 본 연구에 사용한 농노범위(1-20%)에서는 잣 섭취에 의해 혈중 콜레스테롤 함량과 동맥경화지수가 감소하는 효과가 나타나지 않았으며 이는 잣에 함유된 다량의 지방이 섭취됨으로써 잣이 지니는 콜레스테롤 저하효과가 감쇄하였기 때문으로 사료된다. 또한 잣 성분이 HMG-CoA reductase와 cholesterol esterase의 저해활성을 지니는지 확인하기 위하여 hexane과 물을 사용하여 잣 성분을 추출한 후 각 추출물에 대한 HMG-CoA reductase와 cholesterol esterase의 저해활성을 측정한 결과 잣의 hexane 추출물은 66%의 HMG-CoA reductase 저해활성을 지니고 있었으며 물 추출물은 저해활성을 나타내지 않았다. 한편 잣의 hexane 추출물과 물 추출물은 cholesterol esterase에 대한 저해활성은 지니고 있지 않았다. 결론적으로 혈중 콜레스테롤의 함량 저하효과는 가공하지 않은 잣의 섭취에 의해서는 기대하기 어려우므로, 향후 잣의 hexane 추출물 중의 유용성분이 혈중 콜레스테롤 함량 저하효과를 지니는지에 대한 동물실험을 수행할 가치가 있다고 판단된다.

• 생명과학회지
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• 제25권4호
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• pp.425-432
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• 2015

각각의 나라는 민족의 공감성과 문화성이 깃든 고유의 술을 가지고 있으며, 우리나라에는 고유의 전통주 막걸리(탁주)가 있다. 본 연구에서는 주박을 이용한 고부가가치 향장소재 개발을 목표로, 상업적 시설에서 대량생산된 우국생 주박의 ethanol 및 열수 추출물로부터 n-hexane, ethylacetate, butanol을 이용한 순차적 유기용매 분획물과 물 잔류물을 조제한 후, 이들의 혈액응고 저해활성, 혈소판 응집저해 활성 및 인간 적혈구 용혈활성 및 항산화 활성을 평가하였다. 우국생 주박의 수분함량은 80.3%, pH 3.94, brix 13.0 및 알코올 함량은 약 1.8%이었으며, ethanol 추출의 경우 추출효율은 6.62%로 열수 추출의 2.1%보다 3.15배 높은 수율을 나타내었다. 총폴리페놀 및 총플라보노이드 함량 분석결과 주박 ethanol 추출물의 ethylacetate 분획물에서 가장 높은 함량을 나타내었으며, 특히 폴리페놀 함량은 매우 높게 나타났다(128 mg/g). 혈액응고 저해활성을 평가한 결과, ethanol 추출물의 ethylacetate 분획물에서는 5 mg/ml 농도에서 TT, PT, aPTT 모두 15배 이상의 연장된 응고시간을 나타내어 매우 강력한 thrombin, prothrombin 및 coagulation factor 저해활성을 나타내었다. 혈소판 응집저해능 평가에서는 ethanol 추출물의 butanol 분획 및 물 잔류물에서 항혈전제로 사용되고 있는 aspirin 보다 우수한 응집저해능을 확인하였다. 상기 10종 시료들은 0.5 mg/ml 농도까지 적혈구 용혈활성이 나타나지 않았으며, 양호한 radical 소거능을 나타내었다. 본 연구결과는 사료 및 비료로 활용되고 있는 우국생 주박의 활성분획물을 이용하는 경우 고부가가치 항혈전제 개발이 가능함을 제시하고 있다.

• Korean Chemical Engineering Research
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• 제51권3호
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• pp.388-393
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• 2013

본 연구에서는 물리적 강도가 강한 천연 고분자인 박테리아 셀룰로오스(BC)를 기반으로 전기적 성질이 매우 뛰어난 그래핀을 결합시켜 터치 스크린과 같은 투명 전도성 필름을 제조할 수 있는 가능성을 확인하고자 한다. 그래핀을 BC와 결합하기 위해서 라디오파의 인가강도와 처리시간을 달리하여 상온에서 산소 플라즈마 처리를 통해 표면을 개질시켰다. 개질된 그래핀의 물에 대한 접촉각이 $130^{\circ}$에서 $12^{\circ}$로 매우 작아진 것으로 친수성이 향상되었다. 또한, XPS분석에서는 graphene 처리 전 산소함유량 2.99%에서 10.98%로 크게 증가하였다. 그래핀의 손상은 Raman 분석에서 $I_D/I_G$ 비로 정도를 알 수 있다. 처리 전 $I_D/I_G$ 비가 0.11로 손상 정도가 가장 낮았고, 처리 후 0.36~0.43으로 처리 전에 비해 그래핀의 구조적 결함이 증가하였다. 용해시킨 BC에 그래핀을 0~0.04 wt% 첨가하여 제조한 막의 XRD 분석에 의하면 BC막과 plasma 처리된 graphene이 함유된 결합막이 동일한 $2{\theta}$로서 화학적으로 잘 결합되었음을 확인하였다. 이는 SEM 이미지에서 BC와 그래핀의 결합 상태를 확인한 것과 일치하였다. FT-IR 분석에서 플라즈마 처리한 그래핀이 함유된 결합막의 1,000~1,300 $cm^{-1}$ (C=O)에서의 피크가 커진 것으로 보아 plasma 처리된 graphene에서 산소기가 생성되었음을 알 수 있었다. 이와 같은 결과로부터 BC의 물리적인 강점을 기반으로 하여 그래핀을 결합시킨다면 신규의 투명 전도성 소재를 개발할 수 있으리라 사료된다.

• 대한치과기공학회지
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• 제34권3호
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• pp.263-271
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• 2012

Purpose: The purpose of this research was to examine department satisfaction for improving the competitiveness of department of dental technology and providing basic data for students successful guidance. Methods: The study subject were 560 students from 4 colleges, and they were selected by the convenient sampling method. Data for this survey was obtain by self-administration method. This questionnaire consist of general characteristics, the awareness of before entering department of dental technology, the satisfaction of department of dental technology, an opinion about change of one's course and temporary absence. Results: About the time of selecting their major, 70.1% of students answered the most before highschool. Department of dental technology and the most common source of information in selecting a majors is the person oneself(52.6%). The person who answers because of knowing a little bit for the question asking the priori knowledge of department of dental technology showed up as 66.3%. About the motivation for selection their major, 37.4% of students answered the most it seemed to be a future prospect. As to the extend of department satisfaction, the satisfaction showed up as 63.3%, but the extend of satisfaction was exposed to reduce as the grade increased. The dissatisfaction factor is the difficulty of the theory(29.8%). Many students do not want to change their majors even if they are provided with the chance to do so(68.7%). From the survey related to the experience of thinking over temporary absence and drop out, 56.8% of students responded they had experienced thinking about that. Current feelings after department selection was found to be the most significant factor that affects satisfaction of department of dental technology(Adjusted $R^2$=48.3%). Conclusion: The extend of satisfaction of the women is low. The extend of satisfaction reduces as the grade increases. The school subject extend of satisfaction can know that ratio about of considering the leave of absence and voluntary withdrawal increases. Therefore, the plan of education that women can adapt the women o the school subject well and that it can be satisfied is sought for. It is considered that effort promoting the extend of satisfaction is needed as the grade increases.

• 대한치과기공학회지
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• 제35권4호
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• pp.405-414
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• 2013

Purpose: The purpose of this study was to examine the relationship of the general characteristics of health-related majors to their life expectancy scale, depression scale, health perception scale, subjective wellbeing scale, somatic symptom scale and college life stress scale. And it's also meant to analyze influential factors for their stress about college life. Methods: The subjects in this study were the students who were in the department of dental laboratory technology and the department of dental hygiene at a college located in the region of Iksan, North Jeolla Province. Data were gathered in November and December, 2012. The life expectancy scale, depression scale, health perception scale, subjective wellbeing scale, physical symptom scale, somatic symptom scale and college life stress scale of the general characteristics were analyzed by t-test and one way analyses of variance (ANOVA) and the Duncan's multiple range test at the 95% confidence level to assess the statistical significance. And stepwise multiple regression analysis was conducted to determine what factors would affect the stress of the students about college life. The data were analyzed with the windows ver. 12.0(SPSS GmbH, Germany) statistical software program. Results: Among the general characteristics, there were significant differences according to gender and age in all the variables that were life expectancy scale, depression scale, health perception scale, subjective wellbeing scale, physical symptom scale and college life stress scale. 61.3% of the students responded they slept for six hours or less, and the respondents who slept for six hours or less scored significantly statistically lower in health perception scale, subjective wellbeing scale and physical symptom scale. As for college life stress, the respondents who got depressed more often, whose subjective peace or happiness was lower, whose life expectancy was lower, who had worse physical symptoms, whose living standard was lower and whose academic year was lower were under heavier stress about their college lives. Conclusion: As the worse physical health and worse mental health(life expectancy, depression, health perception, subjective wellbeing and physical symptoms, etc.) of the college students led to heavier stress about college life, how to promote their physical health and mental health should discreetly be considered, and every necessary measure should be taken to improve their physical and mental health.

• 한국식품과학회지
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• 제46권4호
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• pp.505-510
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• 2014

본 연구는 고종시 감나무 부위별 수용성 추출물의 항산화 및 항염증에 대한 효과를 조사하였다. 감꼭지와 감잎은 DPPH, ABTS 및 NO 등 라디칼을 효과적으로 제거하는 활성뿐만 아니라 환원력도 우수한 항산화 활성을 보였다. 또한 LPS에 의해 활성화된 설치류 유래 대식세포주인 RAW 264.7 세포에서 NO 생성억제는 감꼭지 추출물이 가장 우수하였지만, $PGE_2$ 생성의 경우 모든 부위의 추출물에서 탁월한 억제 효과가 있었다. 더욱이 활성화된 RAW 264.7 세포에서 감꼭지, 감잎 및 감껍질 추출물은 농도에 의존적으로 TNF-${\alpha}$와 IL-$1{\beta}$를 효과적으로 억제하였다. 이러한 결과는 고종시 감나무 부위별 추출물 중 감꼭지와 감잎은 항산화제뿐만 아니라 항염증에 효과적인 물질이라는 것을 제시해주었고, 감껍질의 경우 비록 항산화 효과는 낮았지만, 우수한 항염효과를 나타내는 물질임을 제시해주었다. 그러므로 고종시 감나무 수용성 추출물은 항산화와 항염 기능을 발휘할 수 있는 식품으로 활용될 수 있을 것이라 사료된다.