• Title/Summary/Keyword: time-dependent effect

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Prostaglandin E2 Up-regulation and Wound Healing Effect of the Ethanol Extract of Eriobotryae Folium in Human Keratinocyte (피부 각질세포에 대한 비파엽 에탄올 추출물의 PGE2 조절 작용과 상처치료 효과)

  • Im, Do Youn;Lee, Kyoung In
    • Korean Journal of Medicinal Crop Science
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    • v.22 no.6
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    • pp.457-462
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    • 2014
  • Prostaglandin (PG) $E_2$ is an important mediator of skin wound healing without excessive scarring and gastric ulcer healing. However, $PGE_2$ has a short lifetime in vivo because it is metabolized rapidly by 15-hydroxyprostaglandin dehydrogenase (15-PGDH). Ethanol extract of Eriobotryae folium (EFEE) elevated intracellular and extracellular $PGE_2$ levels in HaCaT cells and inhibited 15-PGDH ($ED_{50}$ : $168.4{\mu}g/mL$) with relatively low cytotoxicity ($IC_{50}$ : $250.0{\mu}g/mL$). Real-time PCR analysis showed that mRNA expression of cyclooxygenase (COX)-1 and COX-2 enzymes were increased and prostaglandin transporter (PGT) was decreased in HaCaT cells by EFEE. Moreover, wound healing effect of EFEE ($168.4{\mu}g/mL$) was comparable to that of TGF-${\beta}1$ (300 pg/mL) as a positive control. These results demonstrate that EFEE may be valuable therapeutic materials for the treatment of $PGE_2$ level dependent diseases.

Induction of Apoptosis by Aqueous Extract of Cordyceps militaris Through Activation of Caspases and Inactivation of Akt in Human Breast Cancer MDA-MB-231 Cells

  • Jin, Cheng-Yun;Kim, Gi-Young;Choi, Yung-Hyun
    • Journal of Microbiology and Biotechnology
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    • v.18 no.12
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    • pp.1997-2003
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    • 2008
  • Cordyceps militaris is well known as a traditional medicinal mushroom and has been shown to exhibit immunostimulatory and anticancer activities. In this study, we investigated the apoptosis induced by an aqueous extract of C. militaris (AECM) via the activation of caspases and altered mitochondrial membrane permeability in human breast cancer MDA-MB-231 cells. Exposure to AECM induced apoptosis, as demonstrated by a quantitative analysis of nuclear morphological change and a flow cytometric analysis. AECM increased hyperpolarization of mitochondrial membrane potential and promoted the activation of caspases. Both the cytotoxic effect and apoptotic characteristics induced by AECM treatment were significantly inhibited by z-DEVD-fmk, a caspase-3 inhibitor, which demonstrates the important role of caspase-3 in the observed cytotoxic effect. AECM-induced apoptosis was associated with the inhibition of Akt activation in a time-dependent manner, and pretreatment with LY294002, a PI3K/Akt inhibitor, significantly increased AECM-induced apoptosis. The results indicated that AECM-induced apoptosis may relate to the activation of caspase-3 and mitochondria dysfunctions that correlate with the inactivation of Akt.

Column Shortening Prediction of Concrete Filled Tubes using Monte Carlo Method (몬테카를로 기법을 이용한 CFT 기둥축소량의 예측)

  • Jang, Sung-Woo;Song, Hwa-Cheol;Sho, Kwang-Ho
    • Journal of Korean Association for Spatial Structures
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    • v.10 no.1
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    • pp.75-84
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    • 2010
  • According to the available study and experimental data about the long term behavior of CFT(Concrete Filled Tube) columns, the creep and of concrete in CFT columns are smaller than those of RC columns because of the confinement effect of outer steel columns. In this study, the uncertainties associated with assumed values for concrete properties such as strength, creep coefficients, and service load have been considered and analyzed for the prediction of time-dependent column shortening of CFT column. The CFT column shortening analysis using Monte Carlo method is proposed and an of a 37 story tall building with CFT columns is studied for illustration. According to the results obtained by the probability analysis with multi parameters, the effect of variation coefficient for 3 parameters is investigated considering confidence interval.

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Reliability of Maintained Hull Girders of Two Bulk Carrier Designs Subjected to Fatigue and Corrosion

  • Soares, C.Guedes;Garbatov, Y.
    • Journal of Ship and Ocean Technology
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    • v.3 no.1
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    • pp.27-41
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    • 1999
  • The objective of the paper is to study the impact of changing the traditional hull design of bulk carriers by providing them with a double hull while keeping the same deadweight. It is demonstrated that by introducing the double hull the structural reliability is increased throughout the entire life and also the extend of the needed repair is reduced. The results are obtained with recently developed mathematical tools for the reliability assessment of ship hulls subjected to the existence of multiple cracks both in the stiffeners and in the plating and it models the crack growth process. The effect of corrosion is represented as time dependent. The long-term stress range acting on the elements is defined as a function of the local transverse pressure of the internal cargo and outside sea water combined with the stresses resulting from the longitudinal bending of the hull, which is a combined with the stresses resulting from the longitudinal bending of the hull, which is a combineation of horizontal and vertical bending moments. The effect of maintenance actions is modelled as a stochastic process. The results show that a different design of the midship section improves the structural safety and also the economy with respect to structural repair of bulk carriers.

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Quantitative Comparison of Acupuncture Needle Force Generation According to Diameter

  • Lee, YeonSun;Bong, SungMin;Kim, Eun Jung;Lee, Seung Deok;Jung, Chan Yung
    • Journal of Acupuncture Research
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    • v.35 no.4
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    • pp.238-243
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    • 2018
  • Background: Various factors can alter the efficacy of acupuncture treatment, such as the location of points, manipulations, depth of insertion, needle retention time, and needle type. In this study, the effect of needle diameter on the efficacy of acupuncture treatment was quantitatively evaluated. Methods: Five acupuncture needles of different diameters used in clinical practice were compared. Force on the porcine tissue phantom was measured using a sensor. Lifting-thrusting and twisting-rotating movements were performed using a needle insertion-measurement system. After repeated measurements, force magnitude was calculated and compared. Following this, we correlated needle diameter and force magnitude during lifting-thrusting and twisting-rotating movements. Results: The force magnitude was significantly altered between needle diameters during lifting-thrusting movements, as shown by a significant positive correlation between needle diameter and force magnitude. In contrast, there was no difference in force magnitude with different needle diameters during twisting-rotating movements. Conclusion: Needle diameter can significantly affect stimuli and force magnitude dependent upon the type of manipulation. Research into the effect of other needle type characteristics and stimulation method is necessary to fully elucidate the role of acupuncture needle choice in treatment efficacy.

The Effect of Fusible Interlining on the Appearance related Properties & Mechanical Characteristics of the Lyocell Fabrics(II) (리오셀직물의 심지접착에 따른 외관적 성능 및 역학적 특성(II))

  • 김인영;오수민;송화순
    • Journal of the Korean Home Economics Association
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    • v.40 no.7
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    • pp.15-24
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    • 2002
  • In this work, the effect of fusible interlining on the appearance related properties and mechanical characteristics of Lyocell fabric after fusing was investigated. Two different types(20's and 10's) of Lyocell face fabric with six different interlining(by thickness and structure) for earth Lyocell fabric were examined. In order to establish the optimum fusing condition for the different face fabric and interlining, peel strength of each fused fabric was measured, which was dependent on the fusing temperature, pressure, and time. The characteristics related appearance and mechanical characteristics of each fused fabric were determined. The results are as follows: The peel strength was excellent, when the fabric was fused with the force of 3kgf/$textrm{cm}^2$ at $120^{\circ}C$ for 15seconds. Flex stiffness, G, 2HG, 2HG5(shear), B, 2HB(bending) of 100% Lyocell fabric 10's were higher than those of 100% Lyocell 20's. Flex stiffness, crease recovery, G, 2HG, B, 2HB of thicker woven interlining were higher than those of thinner woven interlining. Crease recovery of twill interlining were higher than those of plain interlining. In case of shear and bending properties, however, plain interlining was higher than twill interlining. Flex stiffness, crease recovery, G, 2HG, 2HG5, B, 2HB of nonwoven interlining were higher than those of woven interlining. In case of drapability, however, woven interlining was higher than nonwoven interlining.

Analysis of Time-Dependent Deformation of CFRP Considering the Anisotropy of Moisture Diffusion

  • Arao, Yoshihiko;Koyanagi, Jun;Hatta, Hiroshi;Kawada, Hiroyuki
    • Advanced Composite Materials
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    • v.17 no.4
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    • pp.359-372
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    • 2008
  • The moisture absorption behavior of carbon fiber-reinforced plastic (CFRP) and its effect on dimensional stability were examined. Moisture diffusivity in CFRP was determined by measuring a specimen's weight during the moisture absorption test. Three types of CFRP specimens were prepared: a unidirectionally reinforced laminate, a quasi-isotropic laminate and woven fabric. Each CFRP was processed into two geometries - a thin plate for determination of diffusivity and a rod with a square cross-section for the discussion of two-dimensional diffusion behavior. By solving Fick's law expanded to 3 dimensions, the diffusivities in the three orthogonal directions were obtained and analyzed in terms of the anisotropy of CFRP moisture diffusion. Coefficients of moisture expansion (CMEs) were also obtained from specimen deformation caused by moisture absorption. During moisture absorption, the specimen surfaces showed larger deformation near the edges due to the distribution of moisture contents. This deformation was reasonably predicted by the finite element analysis using experimentally determined diffusivities and CMEs. For unidirectional CFRP, the effect of the fiber alignment on CME was analyzed by micromechanical finite element analysis (FEA) and discussed.

Effect of base isolation systems on increasing the resistance of structures subjected to progressive collapse

  • Tavakoli, Hamid R.;Naghavi, Fahime;Goltabar, Ali R.
    • Earthquakes and Structures
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    • v.9 no.3
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    • pp.639-656
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    • 2015
  • Seismic isolation devices are commonly used to mitigate damages caused by seismic responses of structures. More damages are created due to progressive collapse in structures. Therefore, evaluating the impact of the isolation systems to enhance progressive collapse-resisting capacity is very important. In this study, the effect of lead rubber bearing isolation system to increase the resistance of structures against progressive collapse was evaluated. Concrete moment resisting frames were used in both the fixed and base-isolated model structures. Then, progressive collapse-resisting capacity of frames was investigated using the push down nonlinear static analysis under gravity loads that specified in GSA guideline. Nonlinear dynamic analysis was performed to consider dynamic effects column removal under earthquake. The results of the push down analysis are highly dependent on location of removal column and floor number of buildings. Also, seismic isolation system does not play an effective role in increasing the progressive collapse-resisting capacities of structures under gravity loads. Base isolation helps to localize failures and prevented from spreading it to intact span under seismic loads.

Apoptosis Induction Effect of Zingiberis Rhizoma Extract in Microglia BV-2 Cells

  • Seo, Jeongbin;Oh, Myung Sook;Jang, Young Pyo;Kim, Jeong Hee
    • International Journal of Oral Biology
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    • v.42 no.1
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    • pp.9-15
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    • 2017
  • Microglia have multiple functions in regulating homeostasis of the central nervous system. Microglia cells have been implicated as active contributors to neuron damage in neurodegenerative disorders. In this study, medicinal plant extracts (MPEs) were used to evaluate the cell-death induction effect in microglia BV-2 cells. Among 35 MPEs tested in this study, 4 MPEs showed less than a 30% cell survival after 24 hours of incubation. These were Foeniculi Fructus, Forsythiae Fructus, Zingiberis Rhizoma and Hedera Rhombea. The concentration showed that 50% cell death ($IC_{50}$) occurred with 33, 83, 67 Ed highlight: Please confirm wording, and $81{\mu}/ml$, respectively. For further study, we chose Zingiberis Rhizoma (ZR) which showed a reasonably low $IC_{50}$ value and an induction of cell death in a relatively narrow range. Western blot analysis showed that ZR-treated cells showed activation of caspase-3 and cleavage of PARP Ed highlight: When an acronym is first presented it needs to be spelled out in both dose- and time-dependent manners. However, the level of Bcl-2 and Bax were not changed by ZR-treatment in BV-2 cells. These results suggest that ZR-induced apoptosis in BV-2 cells occured through caspase-3 activation. The results also suggested that ZR may be useful in developing treatments for neurodegenerative diseases.

The effect of herbal medicine on cultured cerebral cortical neurons induced by glutamate neurotoxicity (대뇌피질 신경세포에 미치는 glutamate 독성에 대한 한약재 효능연구)

  • Lee, Mi-Young;Kang, Bong-Joo;Yoon, Yoo-Sik;Hong, Seong-Gil;Gwag, Byoung-Joo;Cho, Dong-Wuk
    • Korean Journal of Oriental Medicine
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    • v.4 no.1 s.4
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    • pp.99-114
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    • 1998
  • The effect of herbal medicine on glutamate mediated neurotoxicity was studied in mouse neurons in primary culture. Immature cerebral cortex neurons (ED14) were maintained for up to 2 weeks in vitro, and we investigated the expression pattern of neuron differentiation and cytotoxicity of cell death, including LDH activity. Neuronal maturation initiated on day 7 and the susceptibility to glutamate-induced cell death was highly sensitive on Day 11 (Fig. 1). Thus, the exposure of the neurons to glutamate caused a dose$(0.1mM{\sim}1mM)$ and time$(4h{\sim}24h)$-dependent neurotoxicity(Fig. 4). Glutamate-induced neurodegeneration was prevented by Shipchondaebotang(SD), Yollyounggobondan(YG), Yugmijihwangwon(YJ) and the death of neurons exposed to glutamate was blocked by the NMDA receptor antagonist MK-801 (Fig. 5).

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