• 생명과학회지
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• 제12권4호
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• pp.496-503
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• 2002

곤충에서 유래한 항균 펩티드, defensin을 항균활성이 있는 활성적인 형태로 분비하는 Pichia 균주를 개발하기 위한 일환으로서 MF$\alpha$1 prerpo sequence와 defensin 합성유전자를 pichia 발현 벡터에 재조합하여 형질전환하고 아미노산 histidine을 첨가하지 않은 최소 배지에서 형질전환체를 일차적으로 선별하였다. 선별한 형질전환체를 대상으로 항생제 G-418에 대한 내성과 M. luteus를 시험균으로 사용하여 생육환 저해를 통한 defensin의 세포 외 분비를 조사하여 4 균주를 선택하고 분석하였다. Southern hybridizaion을 통해 숙주의 염색체 DNA에 삽입한 defensin 유전자가 유지됨을 확인하였으며 전체 RNA를 분리하고 RT-PCR을 수행하여 defensin mRNA를 증폭하고 Southern hybridization을 실시한 결과 증폭된 밴드는 probe로 사용한 defensin 유전자에 의해 양성 신호가 나타났다. 배양시간에 따른 4 균주의 세포성장과 항균활성을 비교하기 위해 BMMY 배지에서 96시간 배양하였다. 세포성장은 모두 유사한 양상을 보였다. 세포성장은 48시간 동안 급격하게 증가한 후 그 이후로는 정지기에 도달되었다. 항균활성도 48시간까지 급격히 증가하였으며 항균활성이 가장 높은 형질전환체 균주 3는 72시간 배양 시 550 AU/$m\ell$을 나타내었다.

• 농업과학연구
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• 제46권4호
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• pp.981-989
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• 2019

Coffee is a popular beverage worldwide, and the scale of consumption is growing rapidly. Many studies have shown that increased coffee consumption has various effects on human health, including beneficial effects on liver diseases, clinical type 2 diabetes, and Parkinson's disease. However, the influences of coffee or caffeine (a component of coffee) on the gut microbiota have not been examined in detail. Here, we tested whether caffeine could alter the antimicrobial activity of L. casei against E. coli. Interestingly, we found that treatment with 0.3 mg/mL caffeine increased the antimicrobial activity of L. casei against E. coli. This activity was not associated with the release of lactic acid but did appear to be related to a heat-labile factor present in the L. casei culture supernatant. Our analyses suggest that the putative antimicrobial factor found in the culture supernatant of L. casei treated with caffeine may be bacteriocin. Taken together, our results suggest that caffeine, which is an ingredient of coffee, increases the antimicrobial activity of L. casei against E. coli through the enhanced production of bacteriocin. These findings also suggest that coffee consumption affects the ability of beneficial bacteria to decrease pathogenic bacteria and/or prevent the progression of bacterial infection-associated diseases in the gut.

• Journal of Gastric Cancer
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• 제3권4호
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• pp.201-205
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• 2003

Purpose: Telomerase activity is generally absent in primary cell cultures and normal tissues. Telomerase is known to be induced upon immortalization or malignant transformation of human cells. Telomerase activity can be increased in immature lymphocytes and activated lymphocytes, but it is not detected in the peripheral blood of normal persons. The authors analyzed peripheral blood telomerase from patients of gastric cancer to evaluate the possibility of using it for diagnosis and as a prognostic factor. Materials and Methods: We obtained blood samples from 11 inflammatory patients and 64 gastric cancer patients. The telomerase activity was measured using the [PCR-ELISA] method. The results were correlated with the T, N, M stage, cell differentiation, vascular, neural, and lymphatic invasion, tumor size, and tumor location. Results: In the 11 inflammatory patients, telomerase activity was not detected while in the gastric cancer patients, a positive rate of $28.1\%$ was noted. The peripheral telomerase activity was not related with tumor size, tumor site, lymphatic and vascular invasion, stage, or histologic differentiation. Conclusion: The peripheral blood telomerase activity for patients of gastric cancer can be utilized as a marker for the diagnosis of not only advanced gastric cancer, but also relatively early stage gastric cancer, but not as a prognostic factor.

• 한국어병학회지
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• 제21권3호
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• pp.247-257
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• 2008

To understand the activity of non-specific defence factors in cultured Sebastes, the antibacterial effect of the serum, skin mucus and homogenate of various organs from cultured oblong rockfish (Sebastes oblongus) and rockfish(Sebastes schlegeli) against pathogenic bacteria, Aeromonas hydrophila, Edwardsiella tarda, Vibrio anguillarum, and Streptococcus sp. was compared with that of flounder(Paralichthys olivaceus) and seabass(Leteolabrax japonicus). And the activities of proteolytic enzyme, chitinolytic enzyme and haemolycin as non-specific defence factor were investigated on the oblong rockfish and rockfish. Samples from oblong rockfish showed the highest antibacterial activity by lysoplate assay on agar plate mixed with pathogens, followed in descending order by rockfish, seabass, and flounder. Turbidimetric assay was carried to evaluate the lysozyme activity of fish samples against lyophilized cells of Micrococcus lysodeiktikus. The serum, kidney, liver, stomach, intestine and eyeball of oblong rockfish and the mucus and gill of rockfish appeared to have the highest lysozyme activity among the fish strains investigated. All samples except skin mucus, liver, and eyeball of oblong rockfish and rockfish showed proteolytic enzyme activity. Chitinolytic enzyme activity was showed in random sampling and haemolytic activity was remarkable in oblong rockfish. Therefore, Sebastes strain was proved to have effective defense mechanisms based on the antibacterial activities, and lysozyme, proteolytic enzyme, chitinolytic enzyme, and haemolycin were considered to act as the non-specific defence factor of Sebastes.

• 방사성폐기물학회지
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• 제15권3호
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• pp.281-299
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• 2017

핵종재고량 관리는 처분시설의 안전한 관리를 위해서는 필수적이다. 본 논문에서는 원자력발전소의 잡고체폐기물에 대하여 기존 발생된 폐기물 자료를 반영한 예측방사능량과 실제 처분시설을 운영하면서 인수되어 처분검사까지 완료된 실제방사능량을 비교분석하였다. 극저준위방사성폐기물에서는 $^{137}CS$, $^{90}Sr$, $^{99}Tc$ 그리고 $^{129}I$ 핵종이 예측방사능량보다 실제방사능량이 높게 평가되었으며, 저준위방사성폐기물에서는 모든 핵종에서 예측방사능량이 실제 방사능량보다 높게 평가되었다. 또한 척도인자에 의한 예측방사능량의 민감도 분석을 통해 준위별 수량 및 총방사능량의 변화추이를 분석하였다. 향후 중저준위방사성폐기물 처분시설의 안전한 운영과 Safety Case 구축을 위한 기초자료로 활용될 것으로 판단된다.

• The Journal of Advanced Prosthodontics
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• 제2권1호
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• pp.18-24
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• 2010

PURPOSE. The aim of this pilot study was to investigate the effect of etched microgrooves on the hydrophilicity of Ti and osteoblast responses. MATERIAL AND METHODS. Microgrooves were applied on Ti to have 15 and $60{\mu}m$ width, and 3.5 and $10{\mu}m$ depth by photolithography, respectively. Further acid etching was applied to create Ti surfaces with etched microgrooves. Both smooth- and acid-etched Ti were used as the controls. The hydrophilicity of Ti was analyzed by determining contact angles. Cell proliferation and osteogenic activity of MC3T3 mouse preosteoblasts were analyzed by bromodeoxyuridine assay and alkaline phosphatase (ALP) activity test, respectively. One-way ANOVA, Pearson's correlation analysis and multiple regression analysis were used for statistics. RESULTS. Etched microgrooves significantly increased the hydrophilicity of Ti compared to the smooth Ti. $60{\mu}m$-wide etched microgrooves significantly enhanced cell proliferation, whereas the osteogenic activity showed statistically non-significant differences between groups. Result of the osteogenic activity significantly correlated with those of hydrophilicity and cell proliferation. Hydrophilicity was determined to be an influential factor on osteogenic activity. CONCLUSION. This study indicates that increase in hydrophilicity of Ti caused by etched microgrooves acts as an influential factor on osteogenic activity. However, statistically non-significant increase in the ALP activity suggests further investigation.

• 한국식품과학회지
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• 제31권6호
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• pp.1421-1426
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• 1999

엿기름의 품질 요소인 당화력(DP)은 보리품종에 따라 큰 차이를 나타내 $139{\sim}220^{\circ}L$의 범위에 있었다. 당화력은 ${\alpha}-amylase$ 보다 ${\beta}-amylase$와 높은 상관관계가 있어 엿기름의 ${\beta}-amylase$ 활성이 매우 중요한 인자였으며, 엿기름 첨가에 따른 amylograph 전분기질 점도 감소는 ${\alpha}-amylase$와 관련이 있는 것으로 확인되었다. 보리품종들의 품질요소들을 분석하여 엿기름 당화력과의 상관관계를 조사한 결과 엿기름의 당화력은 원맥의 품질인자와 상관관계가 별로 높지 않았으나 중량이 낮은 품종이나 덜 풍만한 품종에서 당화력이 높은 경향을 보여주었다. 보리원맥이 지니고 있는 ${\beta}-amylase$ 활성은 엿기름의 당화력과 상관관계가 있는 것으로 평가되었으며 엿기름의 당화력을 예측할 수 있는 잠재적인 당화력으로서 엿기름 제조에 매우 유용한 품질인자인 것으로 판단되었다.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제7권4호
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• pp.359-371
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• 2001

자원제약 하에서의 프로젝트 스케줄링 문제는 많은 불확실성의 요소들을 내포하고 있으며 스케줄의 구성은 전문가에 의한 자의적 판단에 따르는 것이 일반적 현상이다. 전문가는 스케줄을 구성하기 위해 자신의 경험을 토대로 프로젝트 진행을 위한 작업(activity)들을 식별하고 이 작업들 사이의 선행관계를 규정하여 각 작업들에 대한 예상 시간을 이용하여 스케줄을 작성한다. 이 때 대부분의 스케줄링 방법들은 비용과 작업기간 두 요소들 중 한 요소에 집중하게 된다. 또한 스케줄 작성의 중요한 요소인 작업기간 결정이 전문가의 경험에 의존하여 결정됨으로써 결정된 작업기간의 불확실성을 초래할 수 있으며 따라서 이 불확실한 작업기간을 이용하여 구성된 스케줄의 불확실성이 증대되는 문제를 내포하고 있다. 이와 같은 문제 즉 스케줄 구성에 있어 작업기간의 불확실성과 작업비용을 함께 고려하지 못하는 문제를 해결하기 위해 이 논문에서는 Fuzzy 개념을 이용한 작업기간의 정형화를 시도하며 아울러 정형된 퍼지 작업 기간과 결합 가능한 퍼지 작업비용을 도입하여 작업기간과 작업비용을 함께 고려하는 Fuzzy-MOEH 스케줄링 알고리즘을 제안한다. 아울러 이 논문에서 제안한 Fuzzy-MOEH 알고리즘과 기존 MOEH 알고리즘의 수행 결과에 대한 비교를 통해 Fuzzy-MOEH 알고리즘의 효용성 및 특성을 분석한다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.103-107
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• 2005

It has been known that the novel diterphenoids, hericenone and erinacine isolated from the fruiting body and cultured mycelia of Hericium erinaceus showed potent stimulating activity of nerve growth factor (NGF)-synthesis. To investigate the biological activities of extracts from fruiting body, cultured mycelium and cell-free broth of H. erinaceus, the activity experiments of antioxidation and AChE inhibition were carried out. Sephadex G-10 gel filtration followed by HPLC on a ${\mu}Bondapak$ $C_{18}$ column of EtOAc extract from cultured mycelium showed a biological activity.

• International Journal of Oral Biology
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• 제40권1호
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• pp.19-25
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• 2015

Osteocytes may function as mechanotransducers by regulating local osteoclastogenesis. Reduced availability of oxygen, i.e. hypoxia, could occur during disuse, bone development, and fracture. Receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL) is an osteoblast/stromal cell derived essential factor for osteoclastogenesis. The hypoxia induced osteoclastogenesis via increased RANKL expression in osteoblasts was demonstrated. Hypoxic regulation of gene expression generally involves activation of the hypoxia-inducible factor (HIF) transcription pathway. In the present study, we investigated whether hypoxia regulates RANKL expression in murine osteocytes and HIF-$1{\alpha}$ mediates hypoxia-induced RANKL expression by transactivating RANKL promoter, to elucidate the role of osteocyte in osteoclastogenesis in the context of hypoxic condition. The expression levels of RANKL mRNA and protein, as well as hypoxia inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) protein, were significantly increased in hypoxic condition in MLO-Y4s. Constitutively active HIF-$1{\alpha}$ alone significantly increased the levels of RANKL expression in MLO-Y4s under normoxic conditions, whereas dominant negative HIF-$1{\alpha}$ blocked hypoxia-induced RANKL expression. To further explore to find if HIF-$1{\alpha}$ directly regulates RANKL transcription, a luciferase reporter assay was conducted. Hypoxia significantly increased RANKL promoter activity, whereas mutations of putative HIF-$1{\alpha}$ binding elements in RANKL promoter prevented this hypoxia-induced RANKL promoter activity in MLO-Y4s. These results suggest that HIF-$1{\alpha}$ mediates hypoxia-induced up-regulation of RANKL expression, and that in osteocytes of mechanically unloaded bone, hypoxia enhances osteoclastogenesis, at least in part, via an increased RANKL expression in osteocytes.