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Study on Hepatoprotective and Antioxidant Activities of Korean Red Ginseng-Mixed Formula (홍삼복합제의 보간 및 항산화 작용에 대한 연구)

  • Kang, Chang-Hee;Kim, Dong-Hee;Ryu, Shi-Yong;Kim, Sung-Hoon
    • Korean Journal of Pharmacognosy
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    • v.31 no.4
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    • pp.383-389
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    • 2000
  • GRF (Korean Red Ginseng mixed formula) consists of six herbs such as Ginseng Radix rubra Koreana, Lycii Fructus, Artemisiae Capillaris Herba, Poria, and Glycyrrhizae Radix and Hoveniae Fructus. For the evaluation of hepatoprotective effect of GRF, the study was performed on protective effect against hepatic damage induced by galactosamine in vitro and ccl4 in vivo and also elucidate antioxidant activity. In vitro assay with 1.1 mM galactosamine, protection (%) was 44% (GR), and 58% (GRF-A) at 50 ug/ml. GRF effectively protected fatty degenertion and necrosis in murine hepatic damage induced by ccl4. For the -antioxidant study, GRF inhibited hemolysis of erythrocyte and decolored DPPH (2,2-diphenyl-l-picrylhydrazyl) free radical in a dose dependent manner more effetively than GR alone in vitro. GRF and GR significantly suppressed the time course $(1\;hr{\sim}6\;hr)-level$ of MDA (malondialdehyde) following AAPH (2,2'-azo-bis-(2-amidino -propane) dihydrochloride) treatment in vivo as compared with control data. From the results it can be concluded GR and GRF exerted the hepatoprotective effect by dint of antioxidant activity.

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Nonlocal vibration analysis of FG nano beams with different boundary conditions

  • Ehyaei, Javad;Ebrahimi, Farzad;Salari, Erfan
    • Advances in nano research
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    • v.4 no.2
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    • pp.85-111
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    • 2016
  • In this paper, the classical and non-classical boundary conditions effect on free vibration characteristics of functionally graded (FG) size-dependent nanobeams are investigated by presenting a semi analytical differential transform method (DTM) for the first time. Three kinds of mathematical models, namely; power law (P-FGM), sigmoid (S-FGM) and Mori-Tanaka (MT-FGM) distribution are considered to describe the material properties in the thickness direction. The nonlocal Eringen theory takes into account the effect of small size, which enables the present model to become effective in the analysis and design of nanosensors and nanoactuators. Governing equations are derived through Hamilton's principle and they are solved applying semi analytical differential transform method. The good agreement between the results of this article and those available in literature validated the presented approach. The detailed mathematical derivations are presented and numerical investigations are performed while the emphasis is placed on investigating the effect of the several parameters such as small scale effects, spring constant factors, various material compositions and mode number on the normalized natural frequencies of the FG nanobeams in detail. It is explicitly shown that the vibration of FG nanobeams is significantly influenced by these effects. Numerical results are presented to serve as benchmarks for future analyses of FG nanobeams.

Vibration analysis of steel fiber reinforced self-compacting concrete beam on elastic foundation

  • Ozdemir, Mahmut Tunahan;Kobya, Veysel;Yayli, Mustafa Ozgur;Mardani-Aghabaglou, Ali
    • Computers and Concrete
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    • v.27 no.2
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    • pp.85-97
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    • 2021
  • In this study, the effect of steel fiber utilization, boundary conditions, different beam cross-section, and length parameter are investigated on the free vibration behavior of fiber reinforced self-compacting concrete beam on elastic foundation. In the analysis of the beam model recommended by Euler-Bernoulli, a method utilizing Stokes transformations and Fourier Sine series were used. For this purpose, in addition to the control beam containing no fiber, three SCC beam elements were prepared by utilization of steel fiber as 0.6% by volume. The time-dependent fresh properties and some mechanical properties of self-compacting concrete mixtures were investigated. In the modelled beam, four different beam specimens produced with 0.6% by volume of steel fiber reinforced and pure (containing no fiber) SCC were analyzed depending on different boundary conditions, different beam cross-sections, and lengths. For this aim, the effect of elasticity of the foundation, cross-sectional dimensions, beam length, boundary conditions, and steel fiber on natural frequency and frequency parameters were investigated. As a result, it was observed that there is a noticeable effect of fiber reinforcement on the dynamic behavior of the modelled beam.

S100A8 Induces Secretion of MCP-1, IL-6, and IL-8 via TLR4 in Jurkat T Cells

  • Nam, A Reum;Kim, Da Hae;Kim, Mun Jeong;Lee, Ji-Sook;Yang, Seung-Ju;Kim, In Sik
    • Biomedical Science Letters
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    • v.22 no.2
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    • pp.60-64
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    • 2016
  • In the pathogenesis of inflammatory diseases such as allergies, S100A8 acts as an important molecule and T lymphocytes are essential cytokine-releasing cells. In this study, we investigated the effect of S100A8 on release of cytokines, specifically MCP-1, IL-6, and IL-8 in T cells, and its associated signaling mechanism. S100A8 increased secretion of MCP-1, IL-6, and IL-8 in a time- and dose-dependent manner. Elevated secretion of MCP-1, IL-6, and IL-8 due to S100A8 was inhibited by the TLR4 inhibitor TLR4i, the PI3K inhibitor LY294002, the $PKC{\delta}$ inhibitor rottlerin, the ERK inhibitor PD98059, the p38 MAPK inhibitor SB202190, the JNK inhibitor SP600125, and the NF-${\kappa}B$ inhibitor BAY-11-7085. S100A8 induced phosphorylation of ERK, p38 MAPK, and JNK in a time-dependent manner, and activation was suppressed by TLR4i, LY294002, and rottlerin. S100A8 induced NF-${\kappa}B$ activation by $I{\kappa}-B{\alpha}$ degradation, and NF-${\kappa}B$ activity was suppressed by PD98059, SB202190, and SP600125. These results indicate that S100A8 induces cytokine release via TLR4. Study of PI3K, $PKC{\delta}$, MAPKs, and NF-${\kappa}B$ will contribute to elucidation of the S100A8-invovled mechanism.

Induction of Apoptosis by Gagamhwanglyeonhaedog-tang through Activation of Caspase-3 in Human Leukemia Cell Line HL-60 Cells

  • Park Sang Goo;Won Jin Hee;Kim Dong Woung;Moon Goo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.4
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    • pp.1173-1178
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    • 2004
  • Gagamhwanglyeonhaedog-tang(GHH), a Korean genuine medicine, is a newly designed herbal drug formula based on the traditional oriental pharmacological knowledge for the purpose of treating tumorous diseases. Apoptosis is an evolutionarily conserved suicide program residing in cells. It leads to cell death through a tightly regulated process resulting in the removal of damaged or unwanted tissue. In the present study, the apoptosis inducing activities of the decocted water extract of GHH were studied. Results of the 3- [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay showed that GHH had a strong cytotoxic effect on HL-60 cells. The number of live cells was less than 20% after exposure to 1㎎/㎖ GHH for 48 hr. GHH increased cytotoxicity of HL-60 cells in a dose- and time­dependent manner. Cell apoptosis by GHH was confirmed by flow cytometric analysis of the DNA-stained cells. The percentage of apoptotic cells increased to 28%, 31% and 37% 24 hr and 37%, 44% and 81% 48 hr after treatment with 0.01, 0.1 and 1㎎/㎖ GHH, respectively. Flow cytometric analysis of GHH treated HL-60 cells showed increase of hypodiploid apoptotic cells in a dose- and time- dependent manner. DNA fragmentation also occurred in apoptosis and was characterized by a ladder pattern on agarose gel. In addition, GHH (0.01 and 0.1㎎/㎖) increased the secretion of tumor necrosis factor-alpha in 24 and 48 hr. The author showed that GHH-induced apoptosis was accompanied by activation of caspase-3. These results suggest that GHH induces activation of caspase-3 and eventually leads to apoptosis.

Anxiolytic and Antidepressant Activities of Ginsenoside Rb1

  • Choi, Jong-Hyun;Yoon, Seo-Young;Choi, Eun-Joo;Ryu, Yim-Seon;Ko, Hong-Sook;Yim, Dong-Sool;Her, Youl;Lee, Yong-Soo;Song, Mi-Ryoung;Cheong, Jae-Hoon
    • Biomolecules & Therapeutics
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    • v.15 no.1
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    • pp.27-33
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    • 2007
  • The psychopharmacological profile of ginsenosides has not yet been confirmed systematically although various neuropharmacological activities associated with them have been investigated. In the present study, the psychological activities of Rb1 were investigated to evaluate whether it can be used in treatment or prevention of psychological disorders. Rb1 was intravenously injected at doses of O.2,2,5 and 10 mg/kg. The effects of Rb1 on the $Cl^-$ ion influx were investigated using IMR-32 human neuroblastoma cells. Moreover, locomotor activity, forced swimming activity, activity on rotating rod and activity in elevated plus-maze were tested in mice. Rb1 increased the $Cl^-$ influx into the intracell region in a dose-dependent manner. Rb1 did not cause change in behavior in total open field when locomotor activity was tested, however it increased activities, especially, such as rearing frequency in center area. Administration of Rb1 at 0.2 mg/kg significantly reduced activities on rotating rod however administration at high dosages had no effect on them. Rb1 administration decreased animal immobile time in a water chamber in a dose dependent manner, and increased the strong mobile time of animals. In conclusion, the present results demonstrate that Rb1 contributes to the psychopharmacological effects of ginseng and may be used in treatment or prevention of psychological disorders such as anxiety or depression.

Effects of Methanolic Extract from Salvia miltiorrhiza Bunge on in vitro Antithrombotic and Antioxidative Activities (단삼 메탄올 추출물의 항혈전 및 항산화 효과)

  • Yang, Seun-Ah;Im, Nam-Kyung;Lee, In-Seon
    • Korean Journal of Food Science and Technology
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    • v.39 no.1
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    • pp.83-87
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    • 2007
  • Salvia miltiorrhiza Bunge is known to potentially prevent arteriosclerosis and hypertension, but its effects on platelet function are not clear. In this study, we evaluated the in vitro antithrombotic activities of the edible plant extract. Methanol extract of S. miltiorrhiza Bunge exhibited about 70% fibrinolytic activity compared to the plasmin control, and inhibited ADP- and collagen-induced platelet aggregation in a concentration-dependent manner with $IC_{50}$ values of 0.42 and 0.07 mg/mL, respectively. S. miltiorrhiza Bunge extract significantly prolonged the activated partial thromboplastin time (APTT) and prothrombin time (PT) compared with control. Moreover, 0.05 mg/mL S. miltiorrhiza Bunge extract contained 87.3% l,l-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity. In conclusion, S. miltiorrhiza Bunge seemed to enhance antithrombotic activity due to its radical scavenging activity. Based on these data, further examination is required to determine the mechanism of platelet-dependent antithrombosis and the effect of polyphenols on platelet function.

Numerical Formulation of Consolidation Based on Finite Strain Analysis (대변형 압밀방정식의 수식화)

  • Shin, Ho-Sung;Lee, Seung-Rae
    • Journal of the Korean Geotechnical Society
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    • v.29 no.6
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    • pp.77-86
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    • 2013
  • Embankments on soft ground experience significant deformation during time-dependent consolidation settlement, as well as an initial undrained settlement. Since infinitesimal strain theory assumes no configuration change and minute strain during deformation, finite strain analysis is required for better prediction of geotechnical problems involving large strain and geometric change induced by imposed loadings. Updated Lagrangian formulation is developed for time-dependent consolidation combining both force equilibrium and mass conservation of fluid, and mechanical constitutive equation is written in Janumann stress rate. Numerical convergence during Newton's iteration in large deformation analysis is improved by Nagtegaal's approach of considering the effect of rotation in mechanical constitutive relationship. Numerical simulations are conducted to discuss numerical reliability and applicability of developed numerical code: deformation of cantilever beam, two-dimensional consolidation. The numerical results show that developed formulation can efficiently describe large deformation problems. Proposed formulation is expected to facilitate the upgrading of a numerical code based on infinitesimal strain theory to that based on finite strain analysis.

Oxidative Stress-Induced Apoptosis in Chronic Myelogenous Leukemia K562 Cells by an Active Compound from the Dithio-Carbamate Family

  • Khoshtabiat, Laya;Mahdavi, Majid;Dehghan, Gholamreza;Rashidi, Mohammad Reza
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.9
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    • pp.4267-4273
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    • 2016
  • Previous studies suggested that dithio-carbamates are potent apoptosis and anti-apoptosis inducing agents in various cancer cells. Here, the anti-proliferative and apoptosis inducing effects of a new derivative (2-NDC) from the dithio-carbamate family was examined in human leukemia K562 cells. We use thiazolyl blue tetrazolium bromide (MTT) to measure viability and cell growth inhibition. The 2-NDC showed effects on viability in a dose and time-dependent manner, inhibiting proliferation at concentrations of $10-30{\mu}M$ after 24-48 hours of treatment and increasing values after 72 hours at $40-120{\mu}M$. The cytotoxic effect of the compound was calculated with an $IC_{50}$ of $30{\mu}M$ after 24-hour. Apoptosis induction was confirmed by acridine orange-ethidium bromide (AO/EtBr) staining, DNA fragmentation assay, flow cytometric assessment and also caspase-3 activation assay. Furthermore, enzymes level such as superoxide dismutase (SOD) and catalase (CAT) involved in oxidative stress were evaluated. The results of this study demonstrated insignificant increase of intracellular ROS levels for 24 hours and reduction after 48-72 hours. In addition to reduction of intracellular thiol, caspase-3 like activity was also decreased in a time-dependent manner in cells treated with 2-NDC. Thus 2-NDC can be considered as a good candidate for further pharmaceutical evaluations.

Theoretical Studies on Electronic Structure and Absorption Spectrum of Prototypical Technetium-Diphosphonate Complex 99mTc-MDP

  • Qiu, Ling;Lin, Jian-Guo;Gong, Xue-Dong;Ju, Xue-Hai;Luo, Shi-Neng
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2358-2368
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    • 2011
  • Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations, employing the B3LYP method and the LANL2DZ, 6-31G$^*$(LANL2DZ for Tc), 6-31G$^*$(cc-pVDZ-pp for Tc) and DGDZVP basis sets, have been performed to investigate the electronic structures and absorption spectra of the technetium-99m-labeled methylenediphosphonate ($^{99m}Tc$-MDP) complex of the simplest diphosphonate ligand. The bonding situations and natural bond orbital compositions were studied by the Mulliken population analysis (MPA) and natural bond orbital (NBO) analysis. The results indicate that the ${\sigma}$ and ${\pi}$ contributions to the Tc-O bonds are strongly polarized towards the oxygen atoms and the ionic contribution to the Tc-O bonding is larger than the covalent contribution. The electronic transitions investigated by TDDFT calculations and molecular orbital analyses show that the origin of all absorption bands is ascribed to the ligand-to-metal charge transfer (LMCT) character. The solvent effect on the electronic structures and absorption spectra has also been studied by performing DFT and TDDFT calculations at the B3LYP/6-31G$^*$(cc-pVDZ-pp for Tc) level with the integral equation formalism polarized continuum model (IEFPCM) in different media. It is found that the absorption spectra display blue shift in different extents with the increase of solvent polarity.