• YAKHAK HOEJI
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• v.43 no.2
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• pp.198-207
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• 1999

The aim of the present investigation was to examine whether YH439, a hepatoprotective agent, exerts protective effect against hepatotoxicity and reduces the production of cytokines and NO in lipopolysaccharide (LPS)-primed rats with carbon tetrachloride ($CCl_4$). Administration of LPS following a single dose of CCl4 injection resulted in remarkable elevations of the serum $TNF{\alpha},{\;}IL-l{\beta$ and IL-6 level. The serum NO level was moderately elevated and severe liver damage was evidenced by increases in serum alanine aminotransferase (ALT) and sorbitol dehydrogenase (SDH) activities. YH439 decreased the levels of TNF, $IL-l{\beta}$, IL-6, ALT, SDH as well as NO in the serum elevated by CCl4+LPS in a dose-dependent manner. Inducible nitric oxide synthase (iNOS) level was decreased in the liver of rats treated with YH439. The increased iNOS activity induced by LPS and $interferon-{\gamma}$ was significantly decreased in RAW 264.7 cells by YH439 treatment. YH439 increased the GSH level decreased by $CCl_4+LPS$ and suppressed the ratio of GSSG/GSH. The reduction of hepatotoxicity by YH439 may associated with the decrease in the production of cytokines as well as suppression of iNOS protein in conjunction with an increase in the GSH level.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.5
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• pp.237-243
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• 2004

Glial cells are activated in neuropathy and play a key role in hyperalgesia and allodynia. This study was performed to determine whether minocycline could attenuate heat hyperalgesia and mechanical allodynia, and how glial cell activation and nuclear factor kappa B (NF-kappaB) were regulated by minocycline in a model of chronic constriction of sciatic nerve (CCl). When minocycline (50 mg/kg, oral) was daily administered from 1 day before to 9 days after ligation, heat hyperalgesia and mechanical allodynia were attenuated. Furthermore, when minocycline treatment was initiated 1 or 3 days after ligation, attenuation of the hypersensitive behavior was still robust. However, the effect of attenuation was less when minocycline was started from day 5. In order to elucidate the mechanism of pain attenuation by minocycline, we examined the changes of glia and NF-kappaB, and found that attenuated hyperalgesia and allodynia by minocycline was accompanied by reduced microglial activation. Furthermore, the number of NF-kappaB immunoreactive cells increased after CCI treatment and this increase was attenuated by minocycline. We also observed translocation of NF-kappaB into the nuclei of activated glial cells. These results suggest that minocycline inhibits activation of glial cells and NF-kappaB, thereby attenuating the development of behavioral hypersensitivity to stimuli.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.9
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• pp.1-8
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• 2007

In this paper, the new beamforming is proposed for an orthogonal frequency division multiplexing(OFDM) system with multi-input multi-output(MIMO). Through the proposed Pre-FFT beamforming technique for MIMO-OFDM, the multibeams are formed toward each multi-transmitter antenna of the desired user. The proposed beamforming for MIMO-OFDM can reduce cochannel interference and get diversity gain in the multi-user environment. Therefore, the performance of MIMO-OFDM system is very improved. BER performance improvement of the proposed approach is investigated through computer simulation by applying it to MIMO-OFDM system in the multi-user environment.

• Biomedical Science Letters
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• v.10 no.3
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• pp.231-235
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• 2004

This study was investigated the effects of the lower power He-Ne IR laser treatment on the changes of blood biochemical components in the rat liver damaged by the carbon tetrachloride (CCl₄). The twenty one Sprague-Dawley adult male rats weights (260±18.6 g) were designed to the three groups: one control group and two experimental groups, the experimental groups were divided into the CCl₄-treated groups and the laser therapy group (CCl₄+ Laser). The experimental groups were injected twice with CCl₄(1.0 ml/kg body weight) intraperitoneal for two days. Each group was sacrificed after two weeks irradiated with the lower power He-Ne IR laser for ten minutes per every day. The activity of alanine aminotransferase (ALT), lactic dehydrogenase (LDH), alkaline phosphatase (ALP) and the concentration of serum glucose treated with He-Ne IR laser groups was significantly decreased to the conrtol (treated with carbon CCl₄) group. The activity of aspartate aminotransferase (AST) was decreased in the laser group but not significantly, the concentration of the serum cholesterol in the laser group was significantly increased comparing with the control and case control groups. In conclusion, the effect of the lower power He-Ne IR laser treatment is believed to be a possible protective effects for CCl₄ induced acute hepatotoxicity in rats.

• Journal of Technology Innovation
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• v.12 no.1
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• pp.67-114
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• 2004

This study attempts to integrate causal model with competitiveness evaluation model, both of which have developed independently of each other, in connection with many studies on PMES (performance measurement and evaluation system) including the BSC (balanced scorecard) of Kaplan and Norton (1992, 1996). For this attempt, this study is composed of four analyses : First, this study develops a structural model for evaluating and diagnosing corporate ‘comprehensive’ competitiveness including quality competitiveness, derive CCI (comprehensive competitiveness index) and QCI (quality competitiveness index) ; Second, this study analyzes the determinants of quality competitiveness, the impacts of quality competitiveness, on product design and product reliability, and the impacts of product design and product reliability on quality competitiveness in the comprehensive competitiveness evaluation model of this study. Third, this study empirically identifies the positioning of product design in the quality competitiveness evaluation model of this study and the functional relationship between product design and other functions : product development, manufacturing, marketing, and marketing, and sales in the same comprehensive competitiveness evaluation model, estimate the determinants of product design and its impacts, thereby providing some empirical findings for the foundation of design management theory, and Fourth, this study identifies the positioning of product reliability in the same quality competitiveness evaluation model, estimate the reliability function and the functional relationship between product reliability and other dimensions of product quality, and tests the hypotheses on the causality of product reliability.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.2
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• pp.193-201
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• 2011

Clamp type transferring mechanism for package substrate's wet processes was newly developed instead of conventional roller type transferring mechanism. Clamp type transferring mechanism has the advantages of reducing the panel deflection and of minimizing the contact problem between the panel and the transferring mechanism. Individual clamp of the mechanism has two distinct mechanical functions which are perfectly fixing a panel during the transferring and generating adequate tension for the panel. To determine the mechanical parameters of the clamp, panel deflection simulation was conducted and the result was verified by the panel deflection measurement. Also, fixing angle of a clamp could be determined by the free body force analysis of individual clamp. Finally clamp type transferring mechanism was actually manufactured and the transferring performance was verified during the water spraying condition of the package substrate's wet processes.

• Korean Journal of Pharmacognosy
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• v.33 no.4 s.131
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• pp.324-331
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• 2002

This study was performed to investigate the protective effect of Houttuynia cordata Thunb on hepatotoxicity in carbon tetrachloride$(CCI_4)$ intoxicated rats. The examined effects hexane, chloroform, butanol and water fractions prepared from the Houttuynia cordata Thunb methanol exlract and rats were administrated with those orally once a day for successive 6 days, fellowed by treaoent with $CCl_4$ on the sixth day. After 6 days, the activities of aminotransferase, alkalinephosphatase, ${\gamma}-glutamyl$ transpeptidase, lactate dehydrogenase and contents of triglyceride, hepatic lipid peroxide in butanol fraction pretreated rats were significantly decreased compared to the only $CCl_4$ treated rats, also depletion glutathione content induced by treatment with $CCl_4$ was prevented by butanol fraction pretreated rats. In addition, activities of hepatic superoxide dismutase, catalase, glutathione peroxidase in butanol fiaction pretreated rats were significantly decreased compared to the only $CCl_4$ treated rats, but the activity of hepatic glutathione-S-transferase was not significantly effect. These results suggest that butanol fiuction of Houttuynia cordata Thunb methanol extract have potent hepatoprotective effect against carbon tetrachloride intoxicated rats.

• YAKHAK HOEJI
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• v.37 no.5
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• pp.499-503
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• 1993

Betaine, a major component of Lycii Fructus, was evaluated for its anti-hepatotoxic activity on carbon tetrachloride-induced hepatotoxicity in primary cultured rat hepatocytes. Betaine was found to attenuate carbon tetrachloride-induced hepatotoxicity both morphologically and biochemically. Typical hepatocyte necrosis due to carbon tetrachloride seemed to be reduced by 50 to 500 $\mu{M}$ of betaine under microscopical observation. The value of glutamic pyruvic transaminase released from the hepatocytes into the medium significantly decreased as betaine concentration increased. Betaine also significantly elevated the reduced activities of some enzymes, cytochrome P-450, 7-ethoxycoumarin-0-deethylase and glutathione-S-transferase, involved in xenobiotic metabolism due to carbon tetrachloride-induced hepatotoxicity. These results demonstrate a possible hepato-protective role of betaine against fatty liver that could be easily induced by carbon tetrachloride.

• YAKHAK HOEJI
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• v.37 no.5
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• pp.538-543
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• 1993

Effects of betaine, a major component of Lycii Fructus, on carbon tetrachloride intoxicated rats were evaluated. Histological studies showed that betaine had improved the typical necrosis around centrilobular area in liver tissue due to the carbon tetrachloride intoxication. Betaine, whether it was administrated simultaneously or prior to carbon tetrachloride, prevented or retarded the elevation of liver-weight/body-weight ratio due to the carbon tetrachloride intoxication. Betaine also significantly elevated the reduced activities of some enzymes, cytochrome P-450, 7-ethoxycoumarin-0-deethylase and glutathione-S-transferase, involved in xenobiotic metabolism due to carbon tetrachloride intoxication. These results demonstrate a possible hepato-protective role of betaine against fatty liver that could be easily induced by carbon tetrachloride in rat.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.268-271
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• 2008

If a reactor vessel is failed to retain a molten corium in a postulated severe accident, the molten corium is released outside the reactor vessel into a reactor cavity. The molten corium would attack the concrete wall and basemat of the reactor cavity, which may lead to inevitable concrete decompositions and possible radiological releases. In the OECD/MCCI project, a series of tests were performed to secure the data for cooling the molten corium spread out at the reactor cavity and for the long-term CCI (Core Concrete Interaction). Also, a MCCI (Molten Core Concrete Interaction) analysis code, CORQUENCH was upgraded at Argonne National Laboratory with embedding the new models developed for the tests. This paper deals with analyses of MCCI at plant scale under the conditions of top flooding using the upgraded CORQUENCH code. The modeling approach is briefly summarized first, followed by presentation of a validation calculation that illustrates the predicative capability of the modeling tool. With this background in place, the model is then used to carry out a parametric set of scoping calculations that define approximate coolability envelopes for the LCS (Limestone Common Sand) concrete that has been evaluated in the OECD/MCCI project.