• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1979년도 추계학술대회 심포지움
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• pp.246.1-246
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• 1979

A glucose-limited “pH-stat” continuous culture study of Lactobacillus bulgaricus NLS-4 in an anaerobic condition showed the marked effects of environmental pH on end products, fermentation blances and bioenergetic aspects of the organism. Lactic acid was the major end product of fermentation with minor products, such as acetic acid, formic acid and ethanol throughout the pH range tested. In acidic conditions below pH 6.5, a typi-cal pattern of homofermentation was revealed whereas in alkaline conditions, the metabolic pattern was changed from homofermentation to heterofermentation and led to acquire much energy. This metabolic change was likely due to the pH-dependent lactate dehydrogenase activity. Molar growth yields (Yglc=35.5-44.4) and YATP, $18.5\pm2.5$ in average which was 80％ higher than the value ever postulated seemed to be accounted for less requirement of maintenance energy of the organism in the culture conditions.

• Nutrition Research and Practice
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• 제14권5호
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• pp.463-477
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• 2020

BACKGROUND/OBJECTIVES: Many studies have suggested that Rhus verniciflua Stokes (RVS) and its extract are anticancer agents. However, RVS had limited use because it contains urushiol, an allergenic toxin. By improving an existing allergen-removal extraction method, we developed a new allergen-free Rhus verniciflua Stokes extract (RVSE) with higher flavonoid content. In this study, we examined whether RVSE inhibits the ability of AGS gastric cancer cells to migrate and invade. MATERIALS/METHODS: The flavonoids content of RVSE was analyzed by HPLC. The effects of RVSE on migration and invasion in AGS cells were analyzed by each assay kit. Matrix metalloproteinase (MMP)-9, plasminogen activator inhibitor-1 (PAI-1) and urokinase-type plasminogen activator (uPA) protein expression was analyzed by protein antibody array. The Phosphorylation of signal transducer and activator of transcription (STAT) 3 were assayed by Western blot analysis. RESULTS: RVSE treatment with 0-100 ㎍/mL dose-dependently reduced the ability of AGS cells to migrate and invade. Notably, treatment with RVSE strongly inhibited the expression of MMP-9 and uPA and the phosphorylation of STAT3. In contrast, RVSE treatment dramatically increased the expression of PAI-1. These results indicate that the inhibition of MMP-9 and uPA expression and STAT3 phosphorylation and the stimulation of PAI-1 expression contributed to the decreased migration and invasion of AGS cells treated with RVSE. CONCLUSIONS: These results suggest that RVSE may be used as a natural herbal agent to reduce gastric cancer metastasis.

• 대한치과보철학회지
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• 제34권4호
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• pp.657-664
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• 1996

The purpose of this study was to compare the dimensional stability, compression resistance, elastic recovery and surface hardness of elastomeric interocclusal recording materials. Five commonly used elastomeric interocclusal recording materials(Ramitec, Regisil, Blue-Mousse, Stat-Br, Coltoflax) were selected for this study. According to ADA specification No. 19, two types of specimen were fabricated. Cylinder type specimens were used to test compression resistance and elastic recovery and plate type specimens were used to evaluate dimensional stability and surface hardness. Paired t-test was applied to detect significance among the occlusal registration materials. The obtained results were as follows: 1. There were statistical difference in dimensional stability between the elastic interocclusal recording materials. The dimensional stability of silicone was higher than that of polyether tested(p<0.05). 2. Coltoflax was significantly less resistance to compression than the other elastic interocclusal recording materials(p<0.001). 3. The elastic recovery capacity of Blu-Mousse and Stat-Br is better than that of Coltoflax (p<0.01). 4. The surface hardness of Coltoflax was lower than that of Blu-Mousse and Stat-Br(p<0.05). 5. The percentage dimensional change of alll materials was acceptable according to the limid of 0.5% suggeted by ADA specificatin No. 19.

• 대한본초학회지
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• 제37권3호
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• pp.41-47
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• 2022

Objectives : Terminalia chebula (TC) has been used as a traditional remedy to treat gastrointestinal infectious and inflammatory diseases. However, its protective effects and mechanisms against skin inflammation have not been well-elucidated. Thus, the aim of this study is to evaluate the protective effects of the TC water extract and also to suggest a putative mechanism of TC against skin injury on human keratinocytes, HaCaT cells. Methods : HaCaT cells were pre-treated with TC for 1 h and then stimulated with tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) (10 ng/mL each) to induce skin inflammation and injury. After 24 h, the cells were harvested to evaluate the expression of Th2 chemokines, such as C-C motif chemokine ligand 5 (CCL5, also known as RANTES), C-C chemokine ligand 17 (CCL17, also known as TARC) and C-C chemokine ligand 22 (CCL22, also known as MDC). To investigate the regulatory mechanisms of TC, we also assessed the phosphorylation of signal transducer and activator of transcription 1 (STAT1) signaling pathways in HaCaT cells. Results : Treatment of TC decreased the mRNA levels of RANTES, TARC and MDC with a concentration dependent manner against co-stimulation of TNF-α and IFN-γ. In addition, TC significantly reduced TNF-α and IFN-γ induced phosphorylation of STAT1. Conclusions : In summary, we propose that TC may be a promising candidate for anti-inflammatory skin protector through the inhibition of chemokines via STAT1 deactivation.

• Asian Pacific Journal of Cancer Prevention
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• 제16권16호
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• pp.6871-6876
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• 2015

Background: The meningeal hemangiopericytoma (MHPC) is a vascular tumor arising from pericytes. Most intracranial MHPCs resemble meningiomas (MNGs) in their clinical presentation and histological features and may therefore be misdiagnosed, despite important differences in prognosis. Materials and Methods: We report 8 cases of MHPC and 5 cases of MNG collected from 2007 to 2011 from the Neuro-Surgery and Histopathology departments. All 13 samples were re reviewed by two independent pathologists and investigated by immunohistochemistry (IHC) using mesenchymal, epithelial and neuro-glial markers. Additionally, we screened all tumors for a large panel of chromosomal alterations using multiplex ligation probe amplification (MLPA). Presence of the NAB2-STAT6 fusion gene was inferred by immunohistochemical staining for STAT6. Results: Compared with MNG, MHPCs showed strong VIM (100% of cases), CD99 (62%), bcl-2 (87%), and p16 (75%) staining but only focal positivity with EMA (33%) and NSE (37%). The p21 antibody was positive in 62% of MHPC and less than 1% in all MNGs. MLPA data did not distinguish HPC from MNG, with PTEN loss and ERBB2 gain found in both. By contrast, STAT6 nuclear staining was observed in 3 MHPC cases and was absent from MNG. Conclusions: MNG and MHPC comprise a spectrum of tumors that cannot be easily differentiated based on histopathology. The presence of STAT6 nuclear positivity may however be a useful diagnostic marker.

• 한국식품영양과학회지
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• 제45권4호
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• pp.533-541
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• 2016

페놀화합물의 함량이 높다고 알려진 카카오(powder)로부터 카카오 추출물(CE)을 획득한 후, CE가 pancreatic lipase의 활성에 미치는 영향과 CE를 함유한 emulsion의 aging에 의한 가수분해율 변화를 살펴보기 위하여 두 가지 형태의 기질을 사용한 pH-stat digestion model을 이용하였다. Type I 의 경우 소화액에 CE와 콩기름을 첨가하여 emulsion을 제조하였으며 aging time(0, 5, 24시간)에 따른 가수분해 변화를 살펴보았다. CE를 첨가하였을 때의 가수분해율은 CE를 첨가하지 않았을 때와 큰 차이를 보이지 않아 CE가 pancreatic lipase 활성에 영향을 주지 않았다고 판단된다. 그러나 aging time이 지남에 따라 CE를 첨가하였을 때와 CE를 첨가하지 않았을 때의 가수분해율 모두 감소하였다. 이는 CE의 영향보다는 aging time이 길어짐에 따라 emulsion의 안정도가 낮아져 지방구 크기가 증가하여 가수분해율이 모두 감소한 것으로 생각되고, 따라서 이 모델에서는 CE에 의한 가수분해 저하가 크지 않았다. 한편 type II의 경우 먼저 콩기름과 CE, Tween 20를 혼합하고 고압균질기를 사용하여 micro-emulsion을 제조한 후, 이를 기질로 하여 aging time(0, 2, 4, 7, 18, 43일)에 따른 가수분해율 변화를 살펴보았다. 그 결과 aging time에 따라 CE를 첨가하지 않은 control과 CE를 첨가한 CE-emulsion의 가수분해율이 감소하였는데, 특히 control보다 CE-emulsion이 더 많이 감소하여 43일에는 control의 ${\Phi}$ max가 92.13%(0일, 96.53%)였으나 CE-emulsion은 77.69%(0일, 97.91%)를 보이면서 CE-emulsion의 가수분해 반응이 control에 비해 낮았다. 다른 kinetic parameter(k value, $t_{1/2}$ 등)에서도 이와 유사한 경향을 나타냈다.

• Animal cells and systems
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• 제2권1호
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• pp.117-122
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• 1998

D-raf, a Drosophila homolog of the human c-raf-1, is known as a signal transducer in cell proliferation and differentiation. A previous study found that the D-raf gene expression is regulated by the DNA replication-related element (DRE)/DRE-binding factor (DREF) system. In this study, we found the sequences homologous to transcription factor C/EBP, MyoD, STAT and Myc recognition sites in the D-raf promoter. We have generated various base substitutional mutations in these recognition sites and subsequently examined their effects on D-raf promoter activity through transient CAT assays in Kc cells with reporter plasmids p5'-878DrafCAT carrying the mutations in these binding sites. Through gel mobility shift assay using nuclear extracts of Kc cells, we detected factors binding to these recognition sites. Our results show that transcription factor C/EBP, STAT and Myc binding sites in D-raf promoter region play a positive role in transcriptional regulation of the D-raf gene and the Myo D binding site plays a negative role.

• Journal of Microbiology and Biotechnology
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• 제28권6호
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• pp.874-882
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• 2018

Curcumin is known to possess various biological functions, including anti-inflammatory, anti-oxidative, and anti-cancer activities. Natural killer (NK) cells are large lymphocytes that directly kill cancer cells. However, many aggressive cancers, including breast cancer, were reported to escape the successful killing of NK cells in a tumor microenvironment. In this study, we investigated the anti-cancer effect of curcumin in coculture of human breast carcinoma MDA-MB-231 and NK (NK-92) cells. We found that curcumin had an immune-stimulatory effect on NK-92 by increasing the surface expression of the $CD16^+$ and $CD56^{dim}$ population of NK-92. We confirmed that the cytotoxic effect of NK-92 on MDA-MB-231 was significantly enhanced in the presence of curcumin, which was highly associated with the activation of Stat4 and Stat5 proteins in NK-92. Finally, this improved anticancer effect of curcumin was correlated with decreased expression of pErk and PI3K in MDA-MB-231.

• Journal of Microbiology and Biotechnology
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• 제12권5호
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• pp.753-759
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• 2002

$\beta$-Cyclodextrin glucanotransferase ($\beta$-CGTase) was overproduced extracellularly using recombinant E. coli by transforming the plasmid pECGT harboring a secretive signal peptide. The $\beta$-CGTase gene of alkalophilic Bacillus firmus var alkalophilus was inserted into the high expression vector pET20b(+) containing a secretive pelB signal peptide, and then transformed into E. coli BL2l(DE3)pLysS. The optimum culture conditions fer the overproduction of $\beta$-CGTase were determined to be TB medium containing 0.5% (w/v) soluble starch at post-induction temperature of $25^{\circ}C$. A significant amount of $\beta$-CGTase, up to 5.83 U/ml, which was nine times higher than that in the parent strain B. firmus var. alkalophilus, was overproduced in the extracellular compartment. A pH-stat fed-batch cultivation of the recombinant E. coli was also performed to achieve the secretive overproduction of $\beta$-CGTase at a high cell density, resulting in production of up to 21.6 U/ml of $\beta$-CGTase.

• 응용통계연구
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• 제11권1호
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• pp.5-12
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• 1998

최근의 교육 방식은 교수 중심에서 학습 중심으로 변화하고 있으며, 여러 매체의 교육적 활용이 강조되고 있다. 본 연구는 웹상에서 14면 주사위 모의실험을 통하여 통계학의 기본 개념들을 학습할 수 있는 전자교재 "CyberStat"을 소개한다.