• Title/Summary/Keyword: blocking effect

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Effect of zinc oxide nanoparticle types on the structural, mechanical and antibacterial properties of carrageenan-based composite films (산화아연 나노입자 유형이 카라기난 기반 복합 필름의 구조, 기계적 및 항균 특성에 미치는 영향)

  • Ga Young Shin;Hyo-Lyn Kim;So-Yoon Park;Mi So Park;Chanhyeong Kim;Jae-Young Her
    • Food Science and Preservation
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    • v.31 no.1
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    • pp.126-137
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    • 2024
  • In this study, zinc oxide nanoparticles (ZnONPs) were synthesized using three distinct zinc salts: zinc acetate, zinc chloride, and zinc nitrate. These ZnONPs were subsequently utilized in the fabrication of carrageenan-ZnONPs (Car-ZnONPs) composite films. The study assessed influence of the various ZnONPs on the morphological, water vapor barrier, color, optical, and antimicrobial properties of the Car-ZnONPs composite films. The surface morphology and UV-blocking attributes of the composite films were affected by the type of ZnONPs used, but their surface color, transparency, and chemical structure remained unaltered. The composite film's thickness and elongation at break (EB) significantly increased, while the tensile strength significantly decreased. In contrast, film's elastic modulus (EM) and water vapor permeability coefficient (WVP) showed no significant difference. All the composite films with added ZnONPs demonstrated potent antibacterial activity against Escherichia coli O157:H7 and Listeria monocytogenes . Among the carrageenan-based composite films, Car-ZnONPsZC showed the highest antibacterial and UV-blocking properties, and its elongation at break was significantly higher than that of the pure carrageenan films. This suggests that ZnONPs composite films have the potential to be used as an active packaging film, preserve the safety of the packaged food and extend shelf life.

Analysis of Causes of and Solutions to the Stack Effect by Vertical Zoning of High-rise Buildings (초고층 건축물 수직조닝별 연돌효과의 원인 및 해결 방안 분석)

  • Shin, Sang Wook;Ryu, Jong Woo;Jeong, Hee Woong;Kim, Dae Young
    • Journal of the Korea Institute of Building Construction
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    • v.21 no.5
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    • pp.483-493
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    • 2021
  • Urban overcrowding has created an explosive supply and demand for high-rise buildings. High-rise buildings are contributing to enhancing the image of the city by serving as focal points, but due to the stack effect, malfunction of elevator doors, difficulties in opening and closing the doors and windows of the outer wall, smoke and odors spreading to the upper floors, noise, energy loss, fire and pollutants have been causing various unexpected problems such as rapid spread of fire. This study classified high-rise buildings according to their vertical zoning, analyzed the causes of and solutions to the stack effect, and derived design and construction methods. Through the initial plan to block the outside air and securing airtightness through precise construction, we sought ways to secure the airtightness inside and outside the building by actively blocking the airflow from the lower floors. In addition, the facility solution can be a measure to reduce the specific phenomena caused by the stack effect, but it should only be applied to the minimum extent because the potential for secondary damage is high. This study emphasized the need for systematic stack effect management by suggesting design and construction measures for each vertical zoning of the causes and countermeasures of the stack effect. It is expected that this study will be helpful not only for design and construction, but also for building maintenance.

Role of the Fas/Fas Ligand Death Receptor Pathway in Ginseng Saponin Metabolite-Induced Apoptosis in HepG2 Cells

  • Oh Seon-Hee;Yin Hu-Quan;Lee Byung-Hoon
    • Archives of Pharmacal Research
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    • v.27 no.4
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    • pp.402-406
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    • 2004
  • This research team found in previous studies, that the ginseng saponin metabolite IH901 induces apoptosis in HepG2 cells via a mitochondrial-mediated pathway, which resulted in the activation of caspase-9 and subsequently of caspase-3 and -8. Based on these results, the involvement of the Fas/Fas ligand (FasL) death-receptor pathway, in IH901-induced apoptosis in HepG2 cells, was investigated. Levels of Fas and the Fas ligand (FasL) mRNA or protein were not increased by IH901, rather they were decreased significantly at 18 h post treatment. Soluble FasL (sFasL) was detectable by immunoprecipitation analysis En the medium of HepG2 cells treated with IH901. Increased levels of sFasL were inversely correlated with the levels of FasL. Preincubation of HepG2 cells with antagonistic anti-Fas antibody showed little protective effect, if any, on IH901-induced cell death. At a $30{\mu}M$ (24 and 48 h) and $40{\mu}M$ (24 h) concentration of IH901, the cytotoxic effect of IH901 was less then $50\%$, anti-Fas antibody prevented IH901-induced cell death. However, at a $60{\mu}M$ (24 and 48 h) and $40{\mu}M$ (48 h) concentration of IH901, cell death rates were about $80\%$ or more and most of the chemopreventive and chemotherapeutic effects of IH901 were manifested. Blocking the Fas receptor did not influence IH901-induced cell death. These results indicate that the Fas/FasL system is engaged, but not required for IH901-induced cell death, at pharmacologically significant concentrations.

Anti-Inflammatory Effects and Cytoprotective Effects of Smilacis Chinae Radix (토복령의 항염증 및 세포보호 효과에 미치는 영향)

  • Lee, Seon-Goo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.1
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    • pp.57-62
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    • 2009
  • Smilacis Chinae Radix has been used as an anti-inflammatory agent. This study was performed to anti-inflammatory and MAP kinase signaling pathway in vitro. Experimental studies were obtained by measuring the Cytotoxicity, production of NO, PGE2, TNF-$\alpha$ and protein level of catalase, SOD, MAP kinase, The results were summarized as follows: Smilacis Chinae Radix was not cytotoxic effects against Raw264.7 and HEK293 cells. Concentration of $100{\mu}g/m{\ell}$ Smilacis Chinae Radix inhibited the production of NO in the Raw264.7 cell stimulated with LPS. All concentrations of Smilacis Chinae Radix not significantly inhibited the production of PGE2 in the Raw264.7 cell stimulated with LPS. All concentrations of Smilacis Chinae Radix did not inhibit the production of TNF-$\alpha$ in the Raw264.7 cell stimulated with LPS. Smilacis Chinae Radix has not effect of blocking NF-${\kappa}B$ into nucleus in LPS-induced macrophage Raw264.7 cell. Smilacis Chinae Radix has the effect of Cytoprotection through activation of ERK and inhibition of p38 and JNK. Accordingly the results show Smilacis Chinae Radix could induce anti-inflammation and Cytoprotection effects against In vitro, but it needs more research on the precise mechanism of such effects.

Inhibitory Effect of the Ethanol Extract of a Rice Bran Mixture Comprising Angelica gigas, Cnidium officinale, Artemisia princeps, and Camellia sinensis on Brucella abortus Uptake by Professional and Nonprofessional Phagocytes

  • Hop, Huynh Tan;Arayan, Lauren Togonon;Reyes, Alisha Wehdnesday Bernardo;Huy, Tran Xuan Ngoc;Baek, Eun Jin;Min, WonGi;Lee, Hu Jang;Lee, Chun Hee;Rhee, Man Hee;Kim, Suk
    • Journal of Microbiology and Biotechnology
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    • v.27 no.10
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    • pp.1885-1891
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    • 2017
  • In this study, we evaluated the inhibitory effect of a rice bran mixture extract (RBE) on Brucella abortus pathogenesis in professional (RAW 264.7) and nonprofessional (HeLa) phagocytes. We fermented the rice bran mixture and then extracted it with 50% ethanol followed by gas chromatography-mass spectrometry to identify the components in RBE. Our results clearly showed that RBE caused a significant reduction in the adherence of B. abortus in both cell lines. Furthermore, analysis of phagocytic signaling proteins by western blot assay revealed that RBE pretreatment resulted in inhibition of phosphorylation of JNK, ERK, and p38, leading to decline of internalization compared with the controls. Additionally, the intensity of F-actin observed by fluorescence microscopy and FACS was remarkably reduced in RBE-pretreated cells compared with control cells. However, the intracellular replication of B. abortus within phagocytes was not affected by RBE. Taken together, these findings suggest that the phagocytic receptor blocking and suppressive effects of RBE on the MAPK-linked phagocytic signaling pathway could negatively affect the invasion of B. abortus into phagocytes.

Unified solutions for piezoelectric bilayer cantilevers and solution modifications

  • Wang, Xianfeng;Shi, Zhifei
    • Smart Structures and Systems
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    • v.16 no.5
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    • pp.759-780
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    • 2015
  • Based on the theory of piezoelasticity, the static performance of a piezoelectric bilayer cantilever fully covered with electrodes on the upper and lower surfaces is studied. Three models are considered, i.e., the sensor model, the driving displacement model and the blocking force model. By establishing suitable boundary conditions and proposing an appropriate Airy stress function, the exact solutions for piezoelectric bilayer cantilevers are obtained, and the effect of ambient thermal excitation is taken into account. Since the layer thicknesses and material parameters are distinguished in different layers, this paper gives unified solutions for composite piezoelectric bilayer cantilevers including piezoelectric bimorph and piezoelectric heterogeneous bimorph, etc. For some special cases, the simplifications of the present results are compared with other solutions given by other researches based on one-dimensional constitutive equations, and some amendments have been found. The present investigation shows: (1) for a PZT-4 piezoelectric bimorph, the amendments of tip deflections induced by an end shear force, an end moment or an external voltage are about 19.59%, 23.72% and 7.21%, respectively; (2) for a PZT-4-Al piezoelectric heterogeneous bimorph with constant layer thicknesses, the amendments of tip deflections induced by an end shear force, an end moment or an external voltage are 9.85%, 11.78% and 4.07%, respectively, and the amendments of the electrode charges induced by an end shear force or an end moment are both 1.04%; (3) for a PZT-4-Al piezoelectric heterogeneous bimorph with different layer thicknesses, the maximum amendment of tip deflection approaches 23.72%, and the maximum amendment of electrode charge approaches 31.09%. The present solutions can be used to optimize bilayer devices, and the Airy stress function can be used to study other piezoelectric cantilevers including multi-layered piezoelectric cantilevers under corresponding loads.

Typha orientalis inhibits inflammatory cytokine expression through suppression of ERK phosphorylation in HMC-1 cells

  • Choi, In-Young;Na, Ho-Jeong;Um, Jae-Young;Kim, Hyung-Min;Hong, Seung-Heon;Sim, Kuk-Jin;Song, Bong-Keun;Nam, Gi-Hye;Choung, Se-Young;Jeong, Hyun-Ja
    • Advances in Traditional Medicine
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    • v.10 no.1
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    • pp.7-12
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    • 2010
  • Typha orientalis' stem (TOS) is traditionally used as an herbal medicine for difficulty in urination, galactophoritis purulenta, whooping cough, and allergic dermatitis. However, its effect in experimental models remains unknown. Here, we report the effect of TOS on the phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-induced inflammatory cytokine production and extracellular signal-regulated kinase (ERK) activation in the human mast cell line, HMC-1. TOS inhibited PMA plus A23187-induced cytokines such as tumor necrosis factor-alpha (TNF-$\alpha$) and interleukin (IL)-6. Maximal inhibition rate of TNF-$\alpha$ and IL-6 production by TOS (1 mg/ml) was about 44.02%, and 45.20%, respectively (P < 0.05). In addition, TOS inhibited the expression of TNF-$\alpha$ and IL-6 mRNA under the same condition. Moreover, TOS partially blocked PMA plus A23187-induced ERK phosphorylation. These results suggested TOS could inhibit the cytokine production through blocking of ERK activity.

Naltrexone Inhibits Catecholamine Secretion Evoked by Nicotinic Receptor Stimulation in the Perfused Rat Adrenal Medulla

  • Yu, Byung-Sik;Min, Seon-Young;Seo, Yoo-Seok;Choi, Cheol-Hee;Lee, Eun-Hwa;Lim, Dong-Yoon
    • The Korean Journal of Physiology and Pharmacology
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    • v.9 no.4
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    • pp.223-230
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    • 2005
  • The purpose of the present study was to examine the effect of naltrexone, an opioid antagonist, on secretion of catecholamines (CA) evoked by cholinergic nicotinic stimulation and membrane-depolarization from the isolated perfused rat adrenal gland and to establish the mechanism of its action. Naltrexone $(3{\times}10^{-6}M)$ perfused into an adrenal vein for 60 min produced time-dependent inhibition in CA secretory responses evoked by ACh $(5.32{\times}10^{-3}M)$ , high $K^+$ $(5.6{\times}10^{-2}M)$ , DMPP ($10^{-4}$ M) and McN-A-343 $(10^{-4}M)$ . Naltrexone itself did also fail to affect basal CA output. In adrenal glands loaded with naltrexone $(3{\times}10^{-6}M)$ , the CA secretory responses evoked by Bay-K-8644, an activator of L-type $Ca^{2+}$ channels and cyclopiazonic acid, an inhibitor of cytoplasmic $Ca^{2+}-ATPase$, were also inhibited. However, in the presence of met-enkephalin $(5{\times}10^{-6}M)$ , a well-known opioid agonist, the CA secretory responses evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were also significantly inhibited. Collectively, these experimental results demonstrate that naltrexone inhibits greatly CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors as well as that by membrane depolarization. It seems that this inhibitory effect of naltrexone does not involve opioid receptors, but might be mediated by blocking both the calcium influx into the rat adrenal medullary chromaffin cells and the uptake of $Ca^{2+}$ into the cytoplasmic calcium store, which are at least partly relevant to the direct interaction with the nicotinic receptor itself.

Effect of Visual and Somatosensory Information Inputs on Postural Sway in Patients With Stroke Using Tri-Axial Accelerometer Measurement

  • Chung, Jae-yeop
    • Physical Therapy Korea
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    • v.23 no.1
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    • pp.87-93
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    • 2016
  • Background: Posture balance control is the ability to maintain the body's center of gravity in the minimal postural sway state on a supportive surface. This ability is obtained through a complicated process of sensing the movements of the human body through sensory organs and then integrating the information into the central nervous system and reacting to the musculoskeletal system and the support action of the musculoskeletal system. Motor function, including coordination, motor, and vision, vestibular sense, and sensory function, including proprioception, should act in an integrated way. However, more than half of stroke patients have motor, sensory, cognitive, and emotional disorders for a long time. Motor and sensory disorders cause the greatest difficulty in postural control among stroke patients. Objects: The purpose of this study is to determine the effect of visual and somatosensory information on postural sway in stroke patients and carrying out a kinematic analysis using a tri-axial accelerometer and a quantitative assessment. Methods: Thirty-four subjects posed four stance condition was accepted various sensory information for counterbalance. This experiment referred to the computerized dynamic posturography assessments and was redesigned four condition blocking visual and somatosensory information. To measure the postural sway of the subjects' trunk, a wireless tri-axial accelerometer was used by signal vector magnitude value. Ony-way measure analysis of variance was performed among four condition. Results: There were significant differences when somatosensory information input blocked (p<.05). Conclusion: The sensory significantly affecting the balance ability of stroke patients is somatosensory, and the amount of actual movement of the trunk could be objectively compared and analyzed through quantitative figures using a tri-axial accelerometer for balance ability.

Anti-oxidative and anti-inflammatory effect of Do-Ki-Tang methanol extract in mouse macrophage cells (마우스 대식세포에서 도기탕 (導氣湯) 메탄올 추출물의 항산화 및 항염증 효과)

  • Kim, Dong-Wan;Yun, Hyun-Jeong;Heo, Jun-Young;Kim, Tae-Hoon;Cho, Hyun-Jin;Park, Sun-Dong
    • The Korea Journal of Herbology
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    • v.25 no.4
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    • pp.103-112
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    • 2010
  • Objective : The aim of this study was to determine whether methanol extract of Do-Ki-Tang (DKT) inhibit free radical generation and production of nitrite an index of NO, $PGE_2$, iNOS, COX-2 and pro-inflammatory cytokines such as TNF-${\alpha}$, IL-$1{\beta}$, IL-6 and MCP-1 in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Methods : Cytotoxic activity of extract on RAW 264.7 cells was measured using 5-(3-caroboxymeth-oxyphenyl)-2H-tetra-zolium inner salt (MTS) assay. The expression level of inflammatory response-related proteins was confirmed by western blot. The production of proinflammatory cytokines was measured by ELISA. Results : Our results indicated that DKT scavenged DPPH radical and nitric oxide in vitro. Moreover, DKT significantly inhibited the LPS-induced NO, $PGE_2$ production and iNOS, COX-2 expression accompanied by an attenuation of TNF-${\alpha}$, IL-$1{\beta}$, IL-6 and MCP-1 formation in macrophages. Furthermore, DKT treatment also blocked LPS-induced intracellular ROS production and the activation of NF-${\kappa}B$ and MAPKs. Conclusion : Our data suggest that the anti-inflammatory effect of DKT is mediated through down-modulation of pro-inflammatory mediators and cytokines by blocking the signaling pathways of NF-${\kappa}B$ and MAPKs. These inhibitory effects by DKT represent a potential therapeutic approach to the treatment of inflammatory diseases.