• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
• /
• pp.719-724
• /
• 2001

In this study, wedge splitting tensile test(WST) using dye penetration method was carried out to investigate cracking criterion and fracture characteristics of concrete. For the this purpose, three levels of compressive strength of 180, 300 and 600 kgf/$\textrm{cm}^2$ and five testing age of 1, 3, 7, 14 and 28 days were selected as test variables. The specimen was loaded in a controlled manner and then dye was inserted at the load of 40%, 70% of the presumed peak load and at the load of 90% just after peak load. The fracture process zone was measured at each load step of a specimen. Test results were compared with analytic results by linear elastic fracture mechanics(LEFM) and numerical results through fictitious crack model(FCM) and finite element method(FEM).

• Animal Bioscience
• /
• 제36권7호
• /
• pp.1120-1129
• /
• 2023

Objective: This study aimed to determine the protective efficacy of Buddha's Temple (BT) extract against tert-butyl hydroperoxide (t-BHP)-induced oxidative stress in Gallus gallus chicken embryo fibroblast cell line (DF-1) and its effects on the cell lipid metabolism. Methods: In this experimental study, Gallus gallus DF-1 fibroblast cells were pretreated with BT 10^-7 for 24 hours, followed by their six-hour exposure to t-BHP (100 μM). Water-soluble tetrazolium salt-8 (WST-8) assays were performed, and the growth curve was computed. The intracellular gene expression changes caused by BT extract were confirmed through quantitative polymerase chain reaction (qPCR). Flow cytometry, oil red O staining experiment, and thin-layer chromatography were performed for the detection of intracellular metabolic mechanism changes. Results: The WST-8 assay results showed that the BT pretreatment of Gallus gallus DF-1 fibroblast cell increased their cell survival rate by 1.08%±0.04%, decreased the reactive oxygen species (ROS) level by 0.93%±0.12% even after exposure to oxidants, and stabilized mitochondrial activity by 1.37%±0.36%. In addition, qPCR results confirmed that the gene expression levels of tumor necrosis factor α (TNFα), TIR domain-containing adapter inducing IFN-beta (TICAM1), and glucose-regulated protein 78 (GRP78) were regulated, which contributed to cell stabilization. Thin-layer chromatography and oil red O analyses showed a clear decrease in the contents of lipid metabolites such as triacylglycerol and free fatty acids. Conclusion: In this study, we confirmed that the examined BT extract exerted selective protective effects on Gallus gallus DF-1 fibroblast cells against cell damage caused by t-BHP, which is a strong oxidative inducer. Furthermore, we established that this extract significantly reduced the intracellular ROS accumulation due to oxidative stress, which contributes to an increase in poultry production and higher incomes.

• 한국치위생학회지
• /
• 제14권5호
• /
• pp.775-781
• /
• 2014

Objectives : The purpose of the study is to investigate the protective effect of coenzyme $Q_{10}$ on cytotoxicity effect of dental monomers in odontoblast(MDPC-23). Methods : MDPC-23 was incubated with the(co)monomers triethylene glycol dimethacrylate (TEGDMA) with and without addition of coenzyme $Q_{10}$. The cell proliferation and survival was determined using WST-1 assay. The level of reactive oxygen species(ROS) was measured by immunofluorescent staining for DCF-DA. Results : TEGDMA treatment decreased the cell proliferation by dose dependently(0.1, 1, 2.5, 5, 10 mM) on the growth of MDPC-23 cells. Coenzyme $Q_{10}$ showed cell proliferation from 5 to $500{\mu}M$ by WST-1 assay. Pre-treatment coenzyme $Q_{10}$ showed the antioxidant effect on proliferation and viability of MDPC-23 after 48h(p<0.05). The positive cells were observed in non-coenyme $Q_{10}$ treatment group(group 2) in comparison with coenyme $Q_{10}$ pre-treatment group(group 1) by DCF-DA. The fluorescence positive cells showed 14.715(group 1) and 19.788(group 2) using image J system. Conclusions : TEGDMA induced cytotoxicity. The MDPC-23 cell death was associated with the increasing ROS. Coenyme $Q_{10}$ showed the antioxidant effects by decreasing ROS. This effects may contribute to the treatment of periodontal disease induced by TEGDMA after operation.

• 동의생리병리학회지
• /
• 제25권5호
• /
• pp.857-862
• /
• 2011

The purpose of this study is to investigate the anti-proliferative mechanism by Trichosanthes kirilowii (TCK) in MCF-7 human breast carcinoma cell. In this study, we used human breast cancer cell line, Michigan cancer foundation-7 cells (MCF-7 cells). They were co-incubated with 30~200 ${\mu}g$/ml TCK for 48 hours, and cell viability was measured by Water-soluble tetrazolium salt-1 (WST-1) assay. After MCF-7 cells were exposed to 60 ${\mu}g$/ml of TCK for 0, 3, 6, 12, 24, 48 hours, We performed flow analysis cytometry sorting(FACS) and western blot analysis. We investigated the effect of dose-dependent cell growth inhibition by TCK, which could be proved by WST-1 assay. Also, flow cytometry analysis showed that TCK increased percentage of subG1 phase and G2/M phase cell cycle. In addition, TCK induced apoptosis through the expression of caspase-9, -3 and poly(ADP-ribose) polymerase(PARP) activation. Moreover, we showed that ATM-dependent G2/M phase arrest by DNA damage and phosphorylation of chk2, cdc25C, cdc2(Tyr15). Taken together, these results suggest that by G2/M phase arrest through DNA damage and inducing of apoptosis through intrinsic pathway, TCK may have potential tumor suppressor in breast cancer.

• 생명과학회지
• /
• 제22권12호
• /
• pp.1595-1599
• /
• 2012

혈관 증식 질환에서 세포주기 활성화와 진행은 중요한 치료 목적으로 사용된다. Luteolin는 glycosylated 형태로 샐러리, 후추, 들깨 잎 그리고 카밀레 차에 존재하며 항돌연변이, 항종양, 항산화 그리고 항염증을 나타낸다. 본 연구에서는 흰쥐 동맥으로부터 분리한 혈관평활근세포를 배양하여 소태아혈청으로 유도된 증식에서 luteolin 효과에 대해 조사했다. Luteolin이 5% 소태아혈청으로 유도된 흰쥐의 혈관평활근세포 증식과 DNA 합성을 5, 20 그리고 $50{\mu}M$에서 억제했다. 혈관평활근세포 증식을 각각 29.6, 50.8 그리고 83.1% 억제했고 DNA 합성은 각각 25.8, 57.6 그리고 81.0% 억제했다. 게다가, 유세포분석 결과 소태아혈청으로 유도된 혈관평활근세포의 세포주기는 luteolin에 의해 차단되었다. 이러한 결과는 세포독성에 의해서도 나타날 수 있기 때문에 WST-1 분석으로 세포독성을 확인한 결과 세포독성 없이 세포주기를 차단하는 효과임을 확인했다. 이상의 결과들은 luteolin이 혈관스텐트와 동맥경화의 치료를 위한 의미있는 항증식 물질임을 보여준다.

• 콘크리트학회지
• /
• 제9권3호
• /
• pp.127-135
• /
• 1997

본 연구에서는 콘크리트의 피로균열 성장거동을 구명하기 위하여 쐐기쪼갬실험( WST)을 수행하였다. 연구의 주안점인 피로균열 성장거동의 주요영향인자는 콘크리트의 강도로서 28,60,118 MPa 등 3가지의 강도를 변수로 택하였다. 한편, 응력비를 6,13%의 2가지로 변화시켜 그 영향을 관찰하였다. 소정의 응력비을 주기 위하여 최고피로하중수준을 75~85%, 최저응력수준을 5~10%로 각각 유지하였다. 피로실험전에 균열개구변위( CMOD)컴플라이언스 보정 실험을 수행한 후, 그 결과인 균열길이와 컴플라이언스의 관계를 피로실험 중에 균열길이를 예측하는데에 이용하였다. 또한 CMOD컴플라이언스 보정법의 타당성을 검증하기 위하여 선형탄성 파괴역학( LEFM) 및 염색법에 의하여 예측된 균열길이와 비교하였다. 실험결과에 의하여 선형탄성 파괴역학에 근거한 피로균열 성장속도 모델(da/dN- K1 관계)을 제시하였고 콘크리트의 강도가 증가함에 따라 피로균열의 성장속도가 빨라지는 것으로 평가되었다. 또한 응력비가 피로균열 성장속도에 영향을 미치는 것으로 나타났는데 강도가 증가함에 따라 그 정도가 감소하는 경향을 보였다. LEFM 과 염색법 의하여 예측된 균열길이와 비교하여 본 결과 CMOD컴플라이언스 보정법이 쐐기쪼갬실험(WST)에 적용될 수 있음이 검증되었다.

• Journal of Acupuncture Research
• /
• 제25권2호
• /
• pp.75-89
• /
• 2008

목적 : 후박(厚朴)(Magnolia obovata)에서 추출한 낮은 농도의 obovatol 약침액의 RAW264.7 세포에서 LPS로 유발된 염증, $TNF-{\alpha}$로 유발된 human colon carcinoma SW620 및 HCT116 세포의 세포증식에 대한 영향과 그 기전을 살펴보고자 하였다. 방법 : RAW264.7 세포에서 LPS로 염증을 유발하고 낮은 농도의 obovatol 약침액을 처리한 후 cell viability, NO 생성량, iNOS와 COX-2의 발현, $NF-{\kappa}B$활성, 전사능력을 관찰하기 위해 WST-1 assay, NO determination assay, western blot analysis, EMSA, luciferase activity assay를 시행하였고, HCT116, SW620 세포에 $TNF-{\alpha}$로 증식을 유도하고 낮은 농도의 obovatol 약침액을 처리한 후 cell growth, apoptosis 및 apoptosis와 연관된 $NF-{\kappa}B$의 활성 변화를 관찰하기 위해 WST-1, Cell morphogy test, DAPI staining and TUNEL assay, EMSA, luciferase activity assay를 시행하였다. 결과 : 1. RAW264.7 세포에서 낮은 농도의 obovatol 약침액 처리는 $NF-{\kappa}B$의 활성 및 전사능력을 낮추고 iNOS와 COX-2의 발현과 NO 생성을 감소시켜 LPS로 유발된 염증을 억제하였다. 2. HCT116, SW620 세포에서 낮은 농도의 obovatol 약침액 처리는 $NF-{\kappa}B$의 활성을 낮추어 세포자멸사를 촉진함으로써 $TNF-{\alpha}$로 유발된 암세포의 성장을 억제하였다. 결론 : 이상의 결과는 낮은 농도의 obovatol 약침액이 항염 및 인간 전립선암세포주인 SW620, HCT116에 대한 증식억제 효과가 있음을 입증한 것이며, 향후 이를 바탕으로 한 생체 연구에서의 긍정적인 결과는 obovatol 약침액이 만성염증성 질환 및 대장암의 예방과 치료에 대한 효과적인 치료제 개발에 초석이 될 것으로 기대된다.

• IMMUNE NETWORK
• /
• 제3권4호
• /
• pp.276-280
• /
• 2003

Background: Peroxidases (Prx) of the peroxiredoxin family reduce hydrogen peroxide and alkyl hydroperoxides to water and alcohol respectively. Hydrogen peroxide is implicated as an intracellular messenger in various cellular responses such as proliferation and differentiation. And Prx I activity is regulated by Cdc-2 mediated phosphorylation. This work was undertaken to investigate the proliferation role of peroxiredoxin III as a member of Prx family in Prx III overexpressed HeLa cell line. Methods: To provide further evidence of proliferation, we selected Prx III stably expressed HeLa Tet-off cell lines. Cell proliferation was examined by using proliferation reagent WST-1 in the presence or absence of doxycycline. Prx III, 2-cys Prx enzymes exist as homodimer. The activation of Prx III heterodimer with induced and endogenous Prx III was examined by immunoprecipitation. Results: Immunoprecipitation analysis of the induced and endogenous Prx III with anti-myc showed that the induced wild type (WT) and dominant negative (DN) Prx III from HeLa Prx III Tet-off stable cell heterodimerized with endogenous Prx III each other. And the expression level of induced Prx III was examined after addition of doxycycline. By 72 hr, the expression level of induced Prx III was diminished gradually and the half-life of the induced wild type Prx III was approximately 17 hr. The proliferation experiment demonstrated that the relative proliferation value of induced and endogenous WT Prx III stable cell has no changes but the DN Prx III induced HeLa Tet-off stable cells were lower than endogenous Prx III. Conclusion: In conclusion, the HeLa dominant negative Prx III Tet-off stable cells were decreased the proliferation.

• 한국치위생학회지
• /
• 제15권4호
• /
• pp.719-725
• /
• 2015

Objectives: The purpose of this study was to determine the toxic effects of sodium lauryl sulfate(SLS) in human keratinocyte HaCaT cells and mouse fibroblast NIH-3T3 cells. Methods: The effect of sodium lauryl sulfate(SLS) cell viability and proliferation were determined by WST-1 assay and changes shape of nucleus were evaluated by Hoechst staining under fluorescence microscopy. Additionally, observation of cell morphological changes under light microscopy. Results: SLS induced cytotoxicity and a marked apoptosis in both HaCaT and NIH-3T3 cell lines. With the result of the WST-1 assay, SLS induced the cytotoxicity of 0.005% and 0.0075%, 0.01% SLS for 24 h after HaCaT and NIH-3T3 cells in time and dose-dependent manner(p<0.005). SLS inhibited cell growth and caused apoptosis as evidenced by nuclear fragmentation and condensation. Thus, determination of the morphological changes to define apoptosis was visualized using inverted phase contrast microscopy. Conclusions: SLS had toxicity of the human keratinocyte cells and mouse fibroblast cells and this study will provide the basic data for the development of proper SLS concentration in dentifrice.

• 한국응용과학기술학회지
• /
• 제34권2호
• /
• pp.271-279
• /
• 2017

본 연구는 황련으로부터 분리된 fraction의 항균효능과 항산화 효과를 평가하고 그것의 화장품 소재로서의 가능성을 확인하였다. 황련으로부터 분리된 fraction의 항균활성은 Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Candida albicans 균주로 disc diffusion 방법을 통해 생육저해환(clear zone)을 측정하였다. 그 결과 Fr. 1을 제외한 모든 시료에서 S. aureus와 candida. A에서 항균활성을 나타내는 것으로 확인 하였다. 항산화 평가를 위해 황련 fraction의 농도(50, 125, 250) ${\mu}g/mL$에 따라 처리하여 1,1-diphenyl-2-picrylhydrazyl (DPPH) 라디칼 소거능과 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) 양이온 라디칼 소거능을 확인하였다. 그 결과 Fr. 1, 2, 3, 4의 $250{\mu}g/mL$ 농도에서 DPPH 라디칼 소거능 활성이 각 11.4%, 30.3%, 42.0%, 53.1%로 $ABTS^+$ 라디칼 소거능 활성은 동일농도에서 각 28.6%, 96.2%, 98.6%, 97.1%로 나타났다. Fr. 3, 4는 동일농도의 대조군 BHT 활성의 86.5%보다 높은 활성산소 저해능을 보였다. 황련의 세포독성을 측정한 WST assay 결과에서 Fr. 4를 제외하고는 Fr. 1, 2, 3은 독성을 나타내지 않았다. 이러한 결과로 황련으로부터 분리된 fraction은 항균능과 항산화 능을 가지는 화장품 소재로서의 가치를 가진다고 볼 수 있다.