• Title/Summary/Keyword: time-dependent effect

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EGb 761 Protects Cardiac Microvascular Endothelial Cells against Hypoxia/Reoxygenation Injury and Exerts Inhibitory Effect on the ATM Pathway

  • Zhang, Chao;Wang, Deng-Feng;Zhang, Zhuang;Han, Dong;Yang, Kan
    • Journal of Microbiology and Biotechnology
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    • v.27 no.3
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    • pp.584-590
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    • 2017
  • Ginkgo biloba extract (EGb 761) has been widely used clinically to reduce myocardial ischemia reperfusion injury (MIRI). Microvascular endothelial cells (MVECs) may be a proper cellular model in vitro for the effect and mechanism study against MIRI. However, the protective effect of EGb 761 on MVECs resisting hypoxia/reoxygenation (H/R) injury is little reported. In this study, H/R-injured MVECs were treated with EGb 761, and then the cell viability, apoptosis, ROS production, SOD activity, caspase-3 activity, and protein level of ATM, ${\gamma}$-H2AX, p53, and Bax were measured. ATM siRNA was transfected to study the changes of protein in the ATM pathway. EGb 761 presented protective effect on H/R-injured MVECs, with decreasing cell death, apoptosis, and ROS, and elevated SOD activity. Next, EGb 761 could inhibit H/R-induced ATM, ${\gamma}$-H2AX, p53, and Bax in a dose-dependent manner. Moreover, ATM siRNA also could inhibit H/R-induced ATM, ${\gamma}$-H2AX, p53, and Bax. Overall, these findings verify that EGb 761 protects cardiac MVECs from H/R injury, and for the first time, illustrate the influence on the ATM pathway and apoptosis by EGb 761 via dampening ROS.

Antiviral activity of Herba Patrinea (a Chinese medicinal herb) against respiratory syncytial virus in vitro

  • Li, Hong-Yuan;Li, Shan-Shan;Liu, Dian-Li;Dong, Yan-Mei;Tian, Wen-Jing
    • Advances in Traditional Medicine
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    • v.3 no.2
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    • pp.106-110
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    • 2003
  • Respiratory syncytial virus (RSV) has long been considered an important cause of severe lower respiratory tract infection in infants and young children throughout the world. Unfortunately, no effective treatment of RSV exists. Therefore, New agents are needed to reduce the impact of RSV. We have studied the anti-viral effect of traditional Chinese midicinal herbs for over ten years and find Herba Patrinea (a Chinese medicinal herb) has the anti-RSV effect in vitro. In this study, the Herba Patrinea was extracted with hot water, condensed and sterilized. The cytotoxicity of the aqueous extract was tested by adding the diluted extract directly to HeLa cells and its effect on anti-RSV was estimated by the CPEI assay. As a result, the median cytotoxic concentration $(CC_{50})$ of Herba Patrinea was 32 mg/ ml by morphological observation, the median effective concentration (50% effective concentration, $EC_{50}$) of the Herba Patrinea against replication of the Long strain of RSV in HeLa cells were 1.25 mg/ml. The selectivity index $(SI=CC_{50}/EC{50})$ is 25.6. Moreover, Herba Patrinea gave a dose-dependent response in inhibiting RSV. In time of addition experiment, Herba Patrinea inhibited replication of RSV in HeLa cells when it was added at 0h, 2h, and 4h after virus infection. In summary, the results of this study suggest Herba Patrinea may be a novel anti-RSV drug and it is worthy of further studying.

Suppressive Effect of SaengRyoSaMulTang on Activated RBL-2H3 Mast Cells (RBL-2H3 비만세포의 알레르기 염증 반응에 미치는 생료사물탕(生料四物湯)의 영향)

  • Son, Mi-Ju;Han, Jae-Kyung;Kim, Yun-Hee
    • The Journal of Pediatrics of Korean Medicine
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    • v.25 no.1
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    • pp.28-39
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    • 2011
  • Objectives: SaengRyoSaMulTang is a herbal formula in Oriental Medicine, known anti-allergens. However, its mechanism and cellular targets have not been found yet. Thus the study has developed to investigate the suppressive effect of SaengRyoSaMulTang. Methods: In the study, cellular viability, IL-4, IL-13 mRNA expression, IL-4, IL-13 production, manifestations of GATA-1, GATA-2, NF-AT1, NF-AT2, AP-1 and NF-${\kappa}$B p65 transcription factors were examined by Real-Time PCR, ELISA analysis and western blotting. Results: As a result of treating with SaengRyoSaMulTang extract(SRSMT), the study has shown that the amount of Th2 cytokines, which include PI induced IL-4 and IL-13, plays a significant role in suppressing effect. RBL-2H3 mast cells significantly suppressed the PI-induced Th2 cytokine production including IL-4 and IL-13 in a dose dependent manner. PI-induced IL-4 and IL-13 production was significantly suppressed by SRSMT intervention. Western blot analysis of transcription factors involving IL-4 and IL-13 expression also revealed a prominent decreases of mast cell's specific transcription factors including GATA-1, GATA-2, NF-AT2, c-Jun and c-Fos, but NF-${\kappa}$B p65. Conclusions: The study suggests that the anti-allergenic activities of SRSMT may regulate the transcription factors GATA-1, GATA-2, NF-AT2, c-Jun and c-Fos inhibiting Th2 cytokines IL-4 and IL-13 in mast cells.

The effects of the abstracts from Moutan Cortex on an anti-allergic action on B cells and mast cells of the BALB/C mouse (B 임파구(淋巴球)와 비만세포(肥滿細胞)에서 모단피(牡丹皮) 추출물(抽出物)의 항(抗)알러지 작용(作用)에 관(關)한 연구(硏究))

  • Jeen Sok-Chang;Kim Sung-Kyun;Lee Han-Bae;Lee Seung-Hee;Seo Young-Bae;Lee Yong-Gu;Lee Young-Chul;Jang Sung-Ik
    • The Journal of Internal Korean Medicine
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    • v.24 no.1
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    • pp.33-43
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    • 2003
  • Objective : This study was carried out for the purpose of proving the effect of anti-allergic efficacy on B cells and the mast cells of the BALB/C mouse by the abstraction from a Moutan cortex. Methods & Results : In order to know what the effect of an abstraction from Moutan cortex and about the expression of CD23 and IgE, IC-2 cell (mouse mast precursor cells that was dependent on IL-3), it was necessary to be activated. We then analyzed it from the flow of cytometry on the increase and the divorce of the B cells activated by anti-CD40. In order to know what the effect of it was on the organization of cytokine gene expression from the increase and divorce of the B cells and allergic acting by Moutan cortex, we found it necessary to examine the IC-2 cells and B cells. At the same time, as we examined the histamine release of IC-2 cells by ELISA method, we also examined the effect of Moutan cortex on the increase and divorce of the B cells by 3H-thymidine uptake method. We then analyzed the release of IL-4, IgE and histamine. Conclusions : As a results, Moutan Cortex promoted blood supply by extending the blood vessel of nasal mucous, which was contracted by the hypertrophied nasal mucous.

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Effect of Low Intensity Pulsed Ultrasound in Rat Chondrocyte (저강도 맥동성 초음파 적용이 관절연골세포에 미치는 영향)

  • Kim, Eun-Jung;Kim, Gye-Yeop
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.5
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    • pp.1262-1269
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    • 2008
  • Low intensity pulsed ultrasound(LIPUS) is known to accelerate bone regeneration, but the precise cellular signaling mechanism is still unclear. The purpose if this study was to determine the effect of LIPUS on the signaling mechanism of rat chondrocyte. In the explant culture condition, there was inhibition effect of 1 $W/cm^2$ intensity LIPUS on chondrocytes proliferation but chondrocytes proliferation was increased at 0.25 $W/cm^2$ intensity. In addition, western blot analysis of MAPKs showed that LIPUS increased ERK1/2 activity from the 10 min treatment of LIPUS. Hydrogen peroxide($H_2O_2$), resulted in a time- and dose-dependent cell proliferation, which was largely attributed to apoptosis. $H_2O_2$ treatment caused marked sustained nucleus condensation in Hoechst stain. LIPUS and $H_2O_2$ activates phosphorylation of p-ERK1/2 and PD 98059($10^{-5}M$) blocked the effect of LIPUS and $H_2O_2$. Moreover, the synergistic phosphorylation of p44/42 MAPK by $H_2O_2$, LIPUS was selectively inhibited by PD 98059, ERK1/2 inhibitor. In order to determine whether the increase in cell proliferation caused by $H_2O_2$ and LIPUS could be explained by changes in the level of the prostaglandin $E_2$. Our study demonstrated that LIPUS stimulate the cell proliferation via activated phosphorylation of ERK1/2 in condrocyte. LIPUS has anabolic effects on rat cartilage in explant cultures, indicating a potential important method for the treatment of osteoarthritic cartilarge.

Complex Compliance of Rough Rice Kernel under Cyclic Loading (주기적(週期的) 반복하중(反復荷重)을 받는 벼의 복소(複素)컴프라이언스)

  • Kim, M.S.;La, W.J.;Park, J.M.
    • Journal of Biosystems Engineering
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    • v.17 no.1
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    • pp.79-90
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    • 1992
  • Viscoelastic characteristics of agricultural products may be determined through three basic tests ; stress relaxation, creep, and dynamic test. Considering the changeability of living materials, dynamic test in which information is derived in a relatively short time appears to be highly desirable, in which either cyclic stress or cyclic strain is imposed and the remaining quantity (strain or stress) is measured. The periodically varying stress will also result in periodically varying strain which in a viscoelastic material should theoretically be out of phase with the stress, because part of the energy subjected to sample is stored in the material as potential energy and part is dissipated as heat. This behavior results in a complex frequency-dependent compliance denoted by J($i{\omega}$). The complex compliance and therefore the storage compliance, the loss compliance, the phase angle, and percent energy loss for the sample should be obtainable with a given static viscoelastic property of the material under static load. The complex compliance of the rough rice kernel were computed from the Burger's model describing creep behavior of the material which were obtained in the previous study. Also, the effects of cyclic load and moisture content of grain on the dynamic viscoelastic behavior of the samples were analyized. The results obtained from this study were summarized as follows ; 1. The storage compliance of the rough rice kernel slightly decreased with the frequency applied but at above the frequency of 0.1 Hz it was nearly constant with the frequency, and the loss compliance of the sample very rapidly decreased with increase in the frequency on those frequency ranges. 2. It was shown that the storage compliance and the loss compliance of the sample increased with increase in grain moisture content. Effect of grain moisture content on the storage compliance of the sample was highly significant than effect of the frequency applied, but effect of the frequency on the loss compliance of the sample was more significant than effect of grain moisture content. 3. In low moisture content, the percent energy loss of Japonica-type rough rice was much higher than that of Indica-type rough rice, but, in high moisture content, vice versa.

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Effect of Near- and Far-Fault Earthquakes for Seismic Fragility Curves of PSC Box Girder Bridges (PSC 상자형교의 지진취약도 곡선에 대한 근거리 및 원거리 지진의 영향)

  • Jin, He-Shou;Song, Jong-Keol
    • Journal of the Earthquake Engineering Society of Korea
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    • v.14 no.5
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    • pp.53-64
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    • 2010
  • Seismic fragility curves of structures represent the probability of exceeding the prescribed structural damage state for a given various levels of ground motion intensity, such as peak ground acceleration (PGA). This means that seismic fragility curves are essential to the evaluation of structural seismic performance and assessments of risk. Most of existing studies have not considered the near- and far-fault earthquake effect on the seismic fragility curves. In order to evaluate the effect of near- and far-fault earthquakes, seismic fragility curves for PSC box girder bridges subjected to near- and far-fault earthquakes are calculated and compared. The seismic fragility curves are strongly dependent on the earthquake characteristics such as fault distance. This paper suggests that the effect of near- and far-fault earthquakes on seismic fragility curves of PSC box girder bridge structure should be considered.

Relation Between Magnetization Easy Axis and Anisotropic Magnetoresistance in Permalloy Films (퍼멀로이 박막의 자화 용이축과 자기저항 변화와의 상관관계에 대한 연구)

  • Hwang, Tae-Jong;Ryu, Yeung-Shik;Kwon, Jin-Hyuk;Kim, Ki-Hyeon;Kim, Dong-Ho
    • Journal of the Korean Magnetics Society
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    • v.18 no.1
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    • pp.28-31
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    • 2008
  • We studied the effect of easy magnetization axis orientation with respect to the strip direction by measuring the magnetoresistance(MR), the magneto-optic Kerr effect(MOKE), and real-time domain evolution. The five strips were patterned on a single chip with the easy axis orientation of each strip relative to the longitudinal direction by around $0^{\circ}$, $18^{\circ}$, $36^{\circ}$, $54^{\circ}$ and $72^{\circ}$, respectively. The overall shape of field dependent MR was mostly governed by the anisotropy magnetoresistnace. The relative change of the longitudinal MR was significantly increased with increasing angle between the easy axis and strip direction, whereas, the transverse MR variation rate was decreased with increasing angle. Several MR steps were observed during the magnetization reversal, and the simultaneous measurement of the MOKE and the domain images identified that the MR steps were associated with evolution of the oppositely directed magnetic domain.

Effect of corrosion on the ultimate strength of double hull oil tankers - Part I: stiffened panels

  • Kim, Do Kyun;Park, Dae Kyeom;Kim, Jeong Hwan;Kim, Sang Jin;Kim, Bong Ju;Seo, Jung Kwan;Paik, Jeom Kee
    • Structural Engineering and Mechanics
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    • v.42 no.4
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    • pp.507-530
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    • 2012
  • Age-related problems especially corrosion and fatigue are normally suffered by weatherworn ships and aging offshore structures. The effect of corrosion is one of the important factors in the Common Structural Rule (CSR) guideline of the ship design based on a 20 or 25 years design life. The aim of this research is the clarification of the corrosion effect on ultimate strength of stiffened panels on various types of double hull oil tankers. In the case of ships, corrosion is a phenomenon caused by the ambient environment and it has different characteristics depending on the parts involved. Extensive research considering these characteristic have already done by previous researchers. Based on this data, the ultimate strength behavior of stiffened panels for four double hull oil tankers such as VLCC, Suezmax, Aframax, and Panamax classes are compared and analyzed. By considering hogging and sagging bending moments, the stiffened panels of the deck, inner bottom and outer bottom located far away from neutral axis of ship are assessed. The results of this paper will be useful in evaluating the ultimate strength of an oil tanker subjected to corrosion. These results will be an informative example to check the effect of ultimate strength of a stiffened panel according to corrosion addition from CSR for a given type of ship.

Protective Effect of Sesaminol Glucosides on Memory Impairment and ${\beta}$, ${\gamma}$-Secretase Activity In Vivo (Sesaminol Glucosides의 기억력 회복능 및 ${\beta}$, ${\gamma}$-Secretase)

  • Lee, Sun-Young;Son, Dong-Ju;Ha, Tae-Youl;Hong, Jin-Tae
    • YAKHAK HOEJI
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    • v.49 no.2
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    • pp.168-173
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    • 2005
  • Alzheimers disease (AD) is the most prevalent form of neurodegenerations associated with aging in the human population. This disease is characterized by the extracellular deposition of beta-amyloid (A ${\beta}$) peptide in cerebral plaques. The A ${\beta}$ peptide is derived from the ${\beta}$-amyloid precursor protein ( ${\beta}$APP). Photolytic processing of ${\beta}$APP by ${\beta}$-secretase(beta-site APP-cleaving enzyme, BASE) and ${\gamma}$-secretase generates the A ${\beta}$ peptide. Several lines of evidence support that A ${\beta}$-induced neuronal cell death is major mechanisms of development of AD. Accordingly, the ${\beta}$-and ${\gamma}$-secretase have been implicated to be excellent targets for the treatment of AD. We previously found that sesaminol glucosides have improving effect on memory functions through anti-oxidative mechanism. In this study, to elucidate possible other mechanism (inhibition of ${\beta}$-and ${\gamma}$-secretase) of sesaminol glucosides, we examined the improving effect of sesaminol glucosides in the scopolamine (1 mg/kg/mouse)-induced memory dysfunction using water maze test in the mice. Sesaminol glucosides (3.75, 7.5 mg/kg/6ml/day p.o., for 3 weeks) reversed the latency time, distance and velocity by scopolamine in dose dependent manner. Next, ${\beta}$-and ${\gamma}$-secretase activities were determined in different regions of brain. Sesaminol glucosides dose-dependently attenuated scopolamine-induced ${\beta}$-secretase activities in cortex and hippocampous and ${\gamma}$-secretase in cortex. This study therefore suggests that sesaminol glucosides may be a useful agent for prevention of the development or progression of AD, and its inhibitory effect on secretase may play a role in the improving action of sesaminol glucosides on memory function.