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Mechanism of $Ca^{2+}$ -activated $Cl^-$ Channel Activation by Ginsenosides in Xenopus Oocytes

  • Park, Seok;Jung, Se-Yeon;Park, Seong-Hwan;Ko, Sung-Ryong;Hyewon Rhim;Park, Chul-Seung;Nah, Seung-Yeol
    • Journal of Ginseng Research
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    • v.24 no.4
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    • pp.168-175
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    • 2000
  • Relatively little is known about the signaling mechanism of ginseng saponins (ginsenosides), active ingredients of ginseng, in non-neuronal cells. Here, we describe that ginsenosides utilize a common pathway of receptor-mediated signaling pathway in Xenopus oocytes: increase in intracellular $Ca^{2+}$ concentration via phospholipase C (PLC) and $Ca^{2+}$ mobilization. Ginsenosides induced a marked and robust artivation of $Ca^{2+}$-activated Cl- channels in Xenopus oocytes. The effect of ginsenosides was completely reversible, in a dose-dependent manner with EC$_{50}$ of 4.4 $\mu\textrm{g}$/mi, and specifically blocked by niflumic acid, an inhibitor of $Ca^{2+}$-activated Cl- channel. Intracellular injection of BAPIA abolished the effect of ginsenosides. Intracellular injection of GTP${\gamma}$S also abolished the effect of ginsenosides. The effect of gin senosides on $Ca^{2+}$-activated Cl- currents was greatly reduced by the intracellular injection of heparin, an IP$_3$ receptorantagonist or the pretreatment of PLC inhibitor. These results indicate that ginsenosides activate endogenous $Ca^{2+}$-activated Cl- channels via the activation of PLC and the release of $Ca^{2+}$ from the IP$_3$-sensitive intracellular store following the initial interaction with membrane component(s) from extracellular side. This signaling pathway of ginsenosides may be one of the action mechanisms for the pharmacological effects of ginseng.ts of ginseng.

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Characterization of Korean Red Ginseng (Panax ginseng Meyer): History, preparation method, and chemical composition

  • Lee, Sang Myung;Bae, Bong-Seok;Park, Hee-Weon;Ahn, Nam-Geun;Cho, Byung-Gu;Cho, Yong-Lae;Kwak, Yi-Seong
    • Journal of Ginseng Research
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    • v.39 no.4
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    • pp.384-391
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    • 2015
  • It has been reported that Korean Red Ginseng has been manufactured for 1,123 y as described in the GoRyeoDoGyeong record. The Korean Red Ginseng manufactured by the traditional preparation method has its own chemical component characteristics. The ginsenoside content of the red ginseng is shown as Rg1: 3.3 mg/g, Re: 2.0 mg/g, Rb1: 5.8 mg/g, Rc:1.7 mg/g, Rb2: 2.3 mg/g, and Rd: 0.4 mg/g, respectively. It is known that Korean ginseng generally consists of the main root and the lateral or fine roots at a ratio of about 75:25. Therefore, the red ginseng extract is prepared by using this same ratio of the main root and lateral or fine roots and processed by the historical traditional medicine prescription. The red ginseng extract is prepared through a water extraction ($90^{\circ}C$ for 14-16 h) and concentration process (until its final concentration is 70-73 Brix at $50-60^{\circ}C$). The ginsenoside contents of the red ginseng extract are shown as Rg1: 1.3 mg/g, Re: 1.3 mg/g, Rb1: 6.4 mg/g, Rc:2.5 mg/g, Rb2: 2.3 mg/g, and Rd: 0.9 mg/g, respectively. Arginine-fructose-glucose (AFG) is a specific amino-sugar that can be produced by chemical reaction of the process when the fresh ginseng is converted to red ginseng. The content of AFG is 1.0-1.5% in red ginseng. Acidic polysaccharide, which has been known as an immune activator, is at levels of 4.5-7.5% in red ginseng. Therefore, we recommended that the chemical profiles of Korean Red Ginseng made through the defined traditional method should be well preserved and it has had its own chemical characteristics since its traditional development.

Ginsenoside Rh2 attenuates microglial activation against toxoplasmic encephalitis via TLR4/NF-κB signaling pathway

  • Xu, Xiang;Jin, Lan;Jiang, Tong;Lu, Ying;Aosai, Fumie;Piao, Hu-Nan;Xu, Guang-Hua;Jin, Cheng-Hua;Jin, Xue-Jun;Ma, Juan;Piao, Lian-Xun
    • Journal of Ginseng Research
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    • v.44 no.5
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    • pp.704-716
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    • 2020
  • Background: Ginsenoside Rh2 (GRh2) is a characterized component in red ginseng widely used in Korea and China. GRh2 exhibits a wide range of pharmacological activities, such as anti-inflammatory, antioxidant, and anticancer properties. However, its effects on Toxoplasma gondii (T. gondii) infection have not been clarified yet. Methods: The effect of GRh2 against T. gondii was assessed under in vitro and in vivo experiments. The BV2 cells were infected with tachyzoites of T. gondii RH strain, and the effects of GRh2 were evaluated by MTT assay, morphological observations, immunofluorescence staining, a trypan blue exclusion assay, reverse transcription PCR, and Western blot analyses. The in vivo experiment was conducted with BALB/c mice inoculated with lethal amounts of tachyzoites with or without GRh2 treatment. Results and conclusion: The GRh2 treatment significantly inhibited the proliferation of T. gondii under in vitro and in vivo studies. Furthermore, GRh2 blocked the activation of microglia and specifically decreased the release of inflammatory mediators in response to T. gondii infection through TLR4/NF-κB signaling pathway. In mice, GRh2 conferred modest protection from a lethal dose of T. gondii. After the treatment, the proliferation of tachyzoites in the peritoneal cavity of infected mice markedly decreased. Moreover, GRh2 also significantly decreased the T. gondii burden in mouse brain tissues. These findings indicate that GRh2 exhibits an antieT. gondii effect and inhibits the microglial activation through TLR4/NF-κB signaling pathway, providing the basic pharmacological basis for the development of new drugs to treat toxoplasmic encephalitis.

Effects of Subjective Oral Health on the Relationship between Oral Health Beliefs and Total Body Health (구강건강신념이 주관적 구강건강을 매개하여 전신건강에 미치는 영향)

  • Choi, Yu-Jin;Eom, Suk
    • Journal of Convergence for Information Technology
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    • v.10 no.1
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    • pp.211-218
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    • 2020
  • This study conducted a survey of 249 adults to determine the effect of oral health beliefs on total body health by mediating subjective oral health. The results showed that the subject's oral health belief averaged 3.75 points, the component of oral health belief was 3.41, the severity 3.73, the importance 4.22 and the benefit 4.19, and the subjective oral health was 3.77 points and the overall health was 3.06. Oral health belief and subjective oral health were found to have a correlation of wealth (r=-0.54, p<0.001), oral health belief and total body health also had a correlation of wealth(r=-0.30, p<0.001), subjective oral health and total body health had a relationship of justice(r=0.47, p<0.001). It was also found that oral health beliefs affect total body health by fully mediating subjective oral health. Based on these findings, it is thought that oral health education programs for adult oral health beliefs can be developed and utilized as basic data for comprehensive general health care, including oral health care, based on correct knowledge and attitudes.

Research Trend of Soft Magnetic Composite Materials with High Energy Efficiency (고에너지효율 연자성 복합 분말 소재의 연구개발 동향)

  • Kim, Hwi-Jun
    • Journal of the Korean Magnetics Society
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    • v.21 no.2
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    • pp.77-82
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    • 2011
  • The use of soft magnetic materials have been increasing in the various industrial fields according to the increasing demand for high performance, automatic, miniaturing equipments in the recent our life. In this study, we investigated the effect of factors on the core loss and magnetic properties of electrical steel and soft magnetic composites. Furthermore, we reviewed the major efforts to reduce the core loss and improve the soft magnetic properties in the two main soft magnetic materials. Domain purification which results from reduced density of defects in cleaner electrical steels is combined with large grains to reduce hysteresis loss. The reduced thickness and the high electrical conductivity reduce the eddy current component of loss. Furthermore, the coating applied to the surface of electrical steel and texture control lead to improve high permeability and low core loss. There is an increasing interest in soft magnetic composite materials because of the demand for miniaturization of cores for power electronic applications. The SMC materials have a broad range of potential applications due to the possibility of true 3-D electromagnetic design and higher frequency operation. Grain size, sintering temperature, and the degree of porosity need to be carefully controlled in order to optimize structure-sensitive properties such as maximum permeability and low coercive force. The insulating coating on the powder particles in SMCs eliminates particle-to-particle eddy current paths hence minimizing eddy current losses, but it reduces the permeability and to a small extent the saturation magnetization. The combination of new chemical composition with optimum powder manufacturing processes will be able to result in improving the magnetic properties in soft magnetic composite materials, too.

An Empirical Study on the Structural Relationships among Perceived Service Quality, Customer Satisfaction and Relationship Quality in Liner Shipping Companies - Focused on Freight Forwarder - (정기선사에 대한 지각된 서비스품질, 고객만족 및 관계질간의 구조적 관계에 관한 실증연구 - 운송주선인을 중심으로 -)

  • Choi, Young-Ro
    • Journal of Korea Port Economic Association
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    • v.26 no.4
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    • pp.147-167
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    • 2010
  • The purpose of this study is to analyze the components and verify the relationship among service quality, customer satisfaction and relationship quality in liner shipping company. In order to achieve the purpose of this study, literature survey related to service quality, customer satisfaction, relationship quality was carried out and took an empirical analysis by the use of questionnaire method for employees in international freight forwarders. The final results are as follows; First, correlations between service quality and customer satisfaction are found to be positive. But service quality component of tangibles and responsiveness with customer satisfaction are not to be positive. Second, as the other study on the similar logistics industries, the correlation between customer satisfaction and relationship quality is found to be positive in this study.

A Design Solution for a Railway Switch Monitoring System (분기기 진단 시스템 설계에 관한 연구)

  • Choo, Eun-Sang;Kim, Min-Seong;Yoo, Heung-Yeol;Mo, Choong-Seon;Son, Eui-Sik;Park, Seongguen;Lee, Jong-Woo
    • Journal of the Korean Society for Railway
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    • v.18 no.5
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    • pp.439-446
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    • 2015
  • The turnout system, which determines the direction of the train, is not only a key system but also a vulnerable system. Failure of this system may lead to a delay of the train or even casualties. In this light, it is necessary to precisely the conditions of the turnout system. Currently, ROADMASTER of Germany is used as a diagnostic system in Korea. However, a new diagnostic system should be developed for optimized operation of the turnout system with maintenance that is suitable for the Korean railway environment. In this paper, a Fault Tree Analysis for the representative faults of the turnout system is conducted and physical quantities, which can be the cause of the fault, are classified according to the component and function. Also, the measuring factors for the monitoring are derived and a decision making theory is suggested. On the basis of the results, we propose a new turnout diagnostic system that can provide more driverse and precise information than the conventional system.

Determination of Maintenance Period Considering Reliability Function and Mission Reliability of Electromagnetic Valves of EMU Doors Considering Air Leakage Failure (전동차 출입문 전자변 누기고장의 신뢰도 함수와 임무 신뢰도를 고려한 정비 주기 결정)

  • Park, Heuiseop;Koo, Jeongseo;Kim, Gildong
    • Journal of the Korean Society for Railway
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    • v.20 no.5
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    • pp.569-576
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    • 2017
  • The electromagnetic valve of pneumatic doors of EMUs has a high failure rate due to air leakage because it supplies air on and off to operate the doors repeatedly. The electromagnetic valve is a very important safety component for which a very high reliability is required because failure makes it impossible to operate the passenger cars. However, domestic urban railway operators maintain electronic valves of the EMU door under a fixed cycle with a spare period according to the full overhaul cycle of the EMU. An improvement of the current maintenance cycle was suggested based on the reliability function and mission reliability. Using the statistical program MINITAB for the operational data of EMU line 6, we analyzed the characteristics of the fault distribution and derived the shape and scale parameters of the reliability function. If we limit the specific reliability probability to under a certain failure rate and calculate its statistical parameters, we can calculate the allowable inspection period with mission reliability. Through this study, we suggested a maintenance period based on RCM (reliability centered-maintenance) to improve the reliability of electromagnetic valves from 68% to 95%.

Miscibility and Properties of Ethyl-Branched Polyethylene/Ethylene-Propylene Rubber Blends (II) (에틸 가지화된 폴리에틸렌과 에틸렌-프로필렌 고무 블렌드의 혼화성과 물성(II))

  • Cho, Ur-Ryong
    • Elastomers and Composites
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    • v.37 no.2
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    • pp.79-85
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    • 2002
  • Ethyl-branched polyethylene [PE(2)] containing 2mole% ethyl branch and three ethylene-propylene rubbers (EPR's) having the same ethylene(E)-propylene(P) molar ratio(E/P=50/50) with different stereoregularity, that is, random EPR (r-EPR), alternating-EPR (alt-EPR) and isotactic-alternating-EPR (iso-alt-EPR) were mixed for the investigation or their properties depending on the stereoregularity. Crystallinity of the prepared blends decreased with increasing content of amorphous EPR because of a decrease in both the degree of annealing and kinetics of diffusion of the crystallizable polymer content. With blend composition, crystallinity was reduced with the stereoregularity in EPR. The thermodynamic interaction parameter(x) for the three blend systems approximately equals to zero near the melting point. These systems were determined to be miscible on a molecular scale near or above the crystalline melting point or the crystalline PE(2). From the measurement of $T_m$ vs. $T_c$, the behavior of PE(2) is mainly due to a diluent effect of EPR component. The spherulite size measured by small angle light scattering (SALS) technique depended upon blend composition, and stereoregularity of EPR. The size of spherulite was enlarged with the content of rubbery EPR and the decrease of stereoregularity in EPR.

Current and Future Trends of Accelerators and Antidegradants for the Tire Industry

  • Hong, Sung-W.
    • Elastomers and Composites
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    • v.34 no.2
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    • pp.156-176
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    • 1999
  • Rubber chemicals such as accelerators, antidegradants, vulcanizing agents, processing agents and retarders are very important to the production and protection of tires and rubber goods. The use of accelerators and antidegradants are evaluated in various tire components. This paper will focus on how to vulcanize tires economically and maintain the physical properties of each tire component without severe degradation due to oxygen, heat and ozone. Also, new non-nitrosoamine accelerators and non-staining antiozonants will be discussed. Lastly, the future requirements of antidegradants and accelerators in the tire industry will be reviewed. Tires have been vulcanized with Sulfenamides as primary accelerators and either Guamdine's or Thiurams as secondary accelerators to achieve proper properties at service conditions. However, interior components such as the carcass can be vulcanized with Thiazoles as a primary accelerator to cure faster than the external components. Using the combination of Sulfenamide with secondary accelerators in a tire tread compound and the combination of a Thiazole and Guanidine in a carcass compound will be presented with performance data. Uniroyal Chemical and another Rubber Chemical Manufacturer have developed, "Tetrabenzyl Thiuram Disulfide," (TBzTD) as a non-Nitrosoamine accelerator, which could replace Nitrosoamine generating Thiurams. This new accelerator has been evaluated in a tread compound as a secondary accelerator. Also, Flexsys has developed N-t-butyl-2-benzothiazole Sulfenamide (TBSI) as a non-Nitrosoamine accelerator which could replace 2-(Morpholinothio) -benzothiazole (MBS), a scorch delayed Sulfendamide accelerator. TBSI has been evaluated in a Natural Rubber (NR) belt skim compound vs. MBS. An optimum low rolling resistant cure system has been developed in a NR tread with Dithiomorpholine (DTDM). Also, future requirements for developing accelerators will be discussed such as the replacement of DTDM and other stable crosslink systems. Antidegradants are divided into two different types for use in tire compounds. Internal tire compounds such as apex, carcass, liner, wire breaker, cushion, base tread and bead compounds are protected by antioxidants against degradation from oxygen and heat due to mechanical shear. The external components such as sidewall, chafer and cap tread com-pounds are protected from ozone by antiozonants and waxes. Various kinds of staining and non-staining antioxidants have been evaluated in a tire carcass compound. Also, various para-phenylene diamine antiozonants have been evaluated in a tire sidewall compound to achieve the improved lifetime of the tire. New non-staining antiozonants such as 2, 4, 6-tris-(N-1, 4-dimethylpentyl-p-phenylene diamine) 1, 3, 5 Trizine (D-37) and un-saturated Acetal (AFS) will be discussed in the tire sidewall to achieve better appearance. The future requirements of antidegradants will be presented to improve tire performance such as durability, better appearance and longer lasting tires.

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