• Journal of Microbiology and Biotechnology
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• 제16권1호
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• pp.158-162
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• 2006

Cyclic dipeptides isolated from Streptomyces sp. have been shown to have antimicrobial activity as well as other potentially useful biological activities. The purpose of this study was to compare the in vitro activity of two cyclic dipeptides combined against anaerobic bacteria with the activity of other antimicrobial agents. Specifically, the in vitro activity of the combination of two cyclic dipeptides was investigated against 140 clinical isolates of anaerobic bacteria by the agar dilution method and was compared with that of erythromycin, cefoxitin, imipenem, clindamycin, and metronidazole. The cyclic dipeptide combination and imipenem were the most active antimicrobial agents tested. In addition, the cyclic dipeptide combination had a radioprotective effect on five normal human lung fibroblast cells, showing survival rates higher $(>90\%)$ than either of the two cyclic dipeptides alone $(<80\%)$.

• 한국응용과학기술학회지
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• 제27권1호
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• pp.14-19
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• 2010

In this study, the anti-oxidative effects and components of sprout serum were investigated. In the buds, high levels of zinc, iron and manganese were analyzed in addition to copper, magnesium, and potassium. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity of sprout serum was evaluated with $IC_{50}$. $IC_{50}$ of sprout serum was $58.0\;mgmL^{-1}$, and that of vitamin C was $3.7\;mgmL^{-1}$. In the test of superoxide scavenging activity of sprout serum, the activity was dependent on the concentration of serum. In this case, the $IC_{50}$ was 2.0 wt%. Cell viability was detected by using the MTT method. Cultured human fibroblast was treated with 15 mM $H_2O_2$ and cell viability was 70% in case of control. However, the effect of treating 0.5% of sprout serum was similar to that of 0.0001% of vitamin C.

• 응용통계연구
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• 제25권3호
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• pp.415-422
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• 2012

For statistical microarray data analysis, clustering analysis is a useful exploratory technique and offers the promise of simultaneously studying the variation of many genes. However, most of the proposed clustering methods are not rigorously solved for a time-course microarray data cluster and for a fitting time covariate; therefore, a statistical method is needed to form a cluster and represent a linear trend of each cluster for each gene. In this research, we developed a modified hierarchical mixture of an experts model to suggest clustering data and characterize each cluster using a linear mixed effect model. The feasibility of the proposed method is illustrated by an application to the human fibroblast data suggested by Iyer et al. (1999).

• International Journal of Oral Biology
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• 제44권4호
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• pp.191-194
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• 2019

The purpose of this study was to investigate the antimicrobial effects of Australia propolis against cariogenic and periodontopathic bacteria. Antimicrobial activity was determined by evaluating the minimal bactericidal concentration (MBC). Cell cytotoxicity of propolis extract on normal human gingival fibroblast (HGF-1) cells was observed using the methylthiazolyldiphenyl-tetrazolium bromide assay. The data indicated that, with the exception of Aggregatibacter actinomycetemcomitans (KCOM 1306), the MBC values of the propolis strains were 0.25-1% without HGF-1 cell cytotoxicity. These results suggest that propolis can be used to develop oral hygiene products for the prevention of oral infectious disease.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2004년도 The 3rd Annual Conference for The Korean Society for Bioinformatics Association of Asian Societies for Bioinformatics 2004 Symposium
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• pp.117-123
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• 2004

마이크로어레이 (microarray) 기술이 개발된 후로 연관된 유전자 클러스터 (cluster)를 찾는 문제는 깊이 연구되어왔다. 이 문제는 핵심적인 과제 중 하나는 생물학적으로 타당한 클러스터의 수를 결정하는 데 있다. 본 논문은 최적의 클러스터 수를 결정하는 기준을 제시하고, non-negative factorization (NMF)를 이용해 클러스터 centroid의 패턴을 찾는 방법을 제안한다. NMF에 의해 발견된 각각의 패턴은 생물학적 프로세스의 특정 부분으로 해석될 수 있다. NMF는 factor matrix의 entity를 non-negative로 제약 (constraint)하고, 이 제약은 오직 additive combination만 허용하기 때문에 이러한 부분적인 패턴을 찾아낼 수 있다. NMF의 유용성은 이미지 분석과 텍스트 분석에서 이미 입증되어 있다. 본 논문에서 제안한 방법에 의해 위의패턴과 유사한 발현 패턴을 갖는 유전자를 모을 수 있었다. 제안된 방법은 human fibroblast데이터와 yeast cell cycle 데이터에 적용해 성능을 입증하였다.

• 한방안이비인후피부과학회지
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• 제23권3호
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• pp.33-41
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• 2010

Background & Objective : This study was performed to find a new anti-aging, anti-wrinkle agent. Ten kinds of hers were evaluated by proliferation, cytotoxicity, collagen synthesis tests in cultured human dermal fibroblast. Methods : MTT assay was carried out to check cell proliferation, cytotoxic effect of each herbal medicine. Collagen synthesis was investigated by the amount of propeptide using procollagen type-Ⅰ C peptide(PIP) ELISA kit(Takara). Results and Conclusions : There are no cytotoxicity in all group herbs by MTT assay. Collagen synthetic ability was greatest in LYCII FRUCTUS(LF) and was excellent in order of Rehmanniae Radix Preparat(RRP) > Nelumbinis Semen(NS) > Asparai Radix(AR) > Schizandrae Frucus(SF).

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2003년도 제3회 발생공학 국제심포지움 및 학술대회
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• pp.102-102
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• 2003

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.524-527
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• 2002

인간 fibroblasts의 receptor를 통한 LDL의 섭취와 분해에 대하여 보다 개선되어진 수학적/동역학적 모델을 제시하였다. 관련된 동역학적 모델의 hierarchy를 통하여 세포 멤브레인 표면으로 recycle되는 receptor의 선택적 insertion 정도를 나타내는 파라미터, ${\alpha}$를 가지는 모델을 제안하였다. 여러 가지의 LDL 농도의 미디움과 여러 가지의 실험조건에서 모델예측을 수행하였는데, Brown과 Goldstein의 많은 실험데이터에 잘 일치하였다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.157.3-158
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• 2003

The antioxidant and anticancer properties of a medicinal plant, Betula platyphylla var. japonica were investigated. The total methanol extract of B. platyphylla var. japonica had protective effects against hydrogen peroxide ($H_2O_2$) in the Chinese hamster lung fibroblast (V79-4) cell line and induced apoptotic cell death in human promyelocytic leukemia (HL-60) cells, a cancer cell line. B. platyphylla var. japonica extract significantly increased cell viability against $H_2O_2$. The extract also showed high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity ($IC_50$ 2.4 mg/ml) and lipid peroxidation inhibitory activity ($IC_50$ below 4.0 mg/ml). (omitted)

• Journal of Periodontal and Implant Science
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• 제29권1호
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• pp.173-192
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• 1999

The purpose of this study was to evaluate the effects of bioactive glass and natural coral on the human periodontal ligament fibroblast(HPLF) behaviors during the regeneration process of peridontium. To determine the cellular events occuring in the presence of the particles of bioactive glass and natural coral, HPLF were isolated from healthy premolar teeth extracted for orthodontic treatment. Cells were cultured in ${\alpha}$MEM at 37$^{\circ}C$, 5% $CO_2$, 95% humidity incubator. Bioactive glass and natural coral were powdered, and each particles(<40${\mu}$m) were placed on the cultured cells at the concentration of 0.3mg/ml, and 1,0mg/ml for experimental group. In control group no particles were added. And each group was evaluated by examining the cell morphology under phase-contrast micrograph at 4 day and transmission electron micrograph(TEM) and scanning electron micrograph(SEM) at 14 day, alkaline phosphatase activity at 5 and 9 day, protain synthesis at 4 day, DNA synthesis at 1, 2, 3 and 4 day, cell proliferation at 1, 3, 5,7 and 9 day and the formation of bone nodule at 30 day after culturing all groups in mineralizing supplemented mediun, No significant changes in cell morphology by adding these two matirials were found under phase contrast microscopy and TEM. HPLF phagocytocized each particles suggesting that HPLF is involved in the process of resorbing each particles and that bioactive glass were more biocompatible than natural coral. The ALPase activity of bioactive glass 0.3 mg/ml was similar with control groups and all the rests of control groups were significantly low(P<0.01) indicating a transient dedifferentiation of HPLF in the presence of bioactive glass and natural coral particles. There were no significant differences of protein synthesis between all groups. The DNA synthesis in experimental groups were significantly lower than control groups at 1, 2 and 3 day (P<0.01) but became similar to control groups at 4 day. Between control groups, the DNA synthesis in bioactive glass O.3mglml group was significantly higher than other groups(P<0.01). Cell proliferation in natural coral 1.0mg/ml and bioactive glass 1.0mglml groups were significantly lower than control group at 3 day(P<0.05) and there were no differences at 5, 7, 9 day. There were more bone nodule formation in experimental groups than in control groups. In conclusion, these results indicated that bioactive glass and natural coral have some effects of a transient dedifferentiation on HPLF and regeneration of periodontal tissues, however any significant cytotoxic effect on HPLF by these two particles were not found.