• Journal of Ginseng Research
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• 제36권3호
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• pp.263-269
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• 2012

Korean red ginseng has shown therapeutic effects for a number of disease conditions. However, little is known about the anti-inflammatory effect of Korean red ginseng saponin fraction (RGSF) in vitro and in vivo. Therefore, in this study, we showed that RGSF containing 20(S)-protopanaxadiol type saponins inhibited nitric oxide production and attenuated the release of tumor necrotic factor (TNF)-${\alpha}$, interleukin (IL)-6, granulocyte monocyte colony stimulating factor (GMCSF), and macrophage chemo-attractant protein-1 in lipopolysaccharide (LPS) stimulated murine macrophage RAW264.7 cells. Moreover, RGSF down-regulated the mRNA expressions of inducible nitric oxide synthase, cyclooxyginase-2, IL-$1{\beta}$, TNF-${\alpha}$, GMCSF, and IL-6. Furthermore, RGSF reduced the level of TNF-${\alpha}$ in the serum and protected mice against LPS mediated endotoxic shock. In conclusion, these results indicated that ginsenosides from RGSF and their metabolites could be potential sources of therapeutic agents against inflammation.

• Computers and Concrete
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• 제6권5호
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• pp.377-390
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• 2009

In this paper an improved one-dimensional frame element for modelling of reinforced concrete beams and columns subjected to impact is presented. The model is developed in the framework of a flexibility fibre element formulation that ignores the shear effect at material level. However, a simple shear cap is introduced at section level to take account of possible shear failure. The effect of strain rate at the fibre level is taken into account by using the dynamic increase factor (DIF) concept for steel and concrete. The capability of the formulation for estimating the element response history is demonstrated by some numerical examples and it is shown that the developed 1D element has the potential to be used for dynamic analysis of large framed structures subjected to impact of air blast and rigid objects.

• 한국물환경학회지
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• 제29권2호
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• pp.232-238
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• 2013

Water temperature is key factor influencing growth and reproduction of fish and its increase give rise to various physiological changes including gene expression. Heat shock protein (Hsp), one of the molecular chaperones, is highly conserved throughout evolution and its expression is induced by various stressors such as temperature, oxidative, physical and chemical stresses. Here, we isolated partial cDNA clones encoding 70-kDa Hsp (Hsp70) and $\beta$-actin using reverse transcriptase-PCR (RT-PCR) from gut of Rhynchocypris kumgangensis, a Korean indigenous species and cold-water fish, and investigated expression profiles of Hsp70 under an increase of water temperature using $\beta$-actin as an internal control for RT-PCR. Cloned Hsp70 cDNA of R. kumgangensis showed homology to Ctenopharyngodon idella (96%), Hypophthalmichthys molitrix (96%), Danio rerio (93%) and Oncorhynchus mykiss (81%) Hsp70. Cloned $\beta$-actin cDNA of R. kumgangensis showed homology to D. rerio (98%), H. molitrix (97%), C. idella (97%) and O. mykiss (90%) $\beta$-actin. Both mRNA of Hsp70 and $\beta$-actin were expressed in gut, brain, and liver in R. kumgangensis. Futhermore, expression of Hsp70, in brain, was highly augmented by an increase of water temperature. These results suggest that Hsp70 mRNA expression level in brain can be used as a biological molecular marker to represent physiological stress against an increase of water temperature.

• Fisheries and Aquatic Sciences
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• 제20권7호
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• pp.9.1-9.13
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• 2017

Background: Metal-responsive transcription factor-1 (MTF-1) is a key transcriptional regulator playing crucial roles in metal homeostasis and cellular adaptation to diverse oxidative stresses. In order to understand cellular pathways associated with metal regulation and stress responses in Pacific abalone (Haliotis discus hannai), this study was aimed to isolate the genetic determinant of abalone MTF-1 and to examine its expression characteristics under basal and experimentally stimulated conditions. Results: The abalone MTF-1 shared conserved features in zinc-finger DNA binding domain with its orthologs; however, it represented a non-conservative shape in presumed transactivation domain region with the lack of typical motifs for nuclear export signal (NES) and Cys-cluster. Abalone MTF-1 promoter exhibited various transcription factor binding motifs that would be potentially related with metal regulation, stress responses, and development. The highest messenger RNA (mRNA) expression level of MTF-1 was observed in the testes, and MTF-1 transcripts were detected during the entire period of embryonic and early ontogenic developments. Abalone MTF-1 was found to be Cd inducible and highly modulated by heat shock treatment. Conclusion: Abalone MTF-1 possesses a non-consensus structure of activation domains and represents distinct features for its activation mechanism in response to metal overload and heat stress. The activation mechanism of abalone MTF-1 might include both indirect zinc sensing and direct de novo synthesis of transcripts. Taken together, results from this study could be a useful basis for future researches on stress physiology of this abalone species, particularly with regard to heavy metal detoxification and thermal adaptation.

• 대한산업공학회지
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• 제25권1호
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• pp.67-74
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• 1999

Market share is one of the most important measures in the valuation of prospering firm. It plays a role of composite indicator for the competitiveness of firm. So, the understanding of the underlying process of market share is inevitable factor for the econometricians and the business engager. Lately, the Korean Economy has been placed in the control of IMF. This shock will cause a lot of influence over the domestic economy. The idea that the information about the past shock-response experience will do us good for dealing with this kind of economic shocks is not new. Among numerous markets, we pay attention to the durable goods market, especially automobile market. The automobile market has large repercussion effect over the domestic economy on the issue of both national employment and technology integration. We divided the Korean automobile market into three segments: small, medium, and large-sized car, while each proportion of these segments has been changing slowly. We propose a Bayesian approach to detect and forecast structural changes in time series of the market shares in the domestic automobile market, especially for level shifts and drift changes, and compare the empirical results with other existing approaches.

• 보건교육건강증진학회지
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• 제29권5호
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• pp.13-26
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• 2012

Objectives: The purpose of this study was to identify the relationship between resilience of migrant workers and their mental health for improving their quality of life and adaptation in Korean society. Methods: Data were collected from March 21 to May 7, 2011. The participants included 488 migrant workers who lived in Busan Metropolitan City or Gyoungnam province. Results: First, heavy working burdens and lack of rests, low wages, poor living environments, low economic status & deficiency of living necessities, hard physical labors, and conflicts with Korean workers had negative effects on mental health. Second, high perceived stress caused by usual 'living difficulties', high 'cutural shock', high feeling of 'social isolation', and high discomfort from 'lack of Korean language proficiency' gave negative effects on migrant worker's mental health. Third, the most important factor on the mental health was the 'cultural shock' among stressors. Even though many stressors existed among migrant workers, these negative effects on mental health were lessened by their high resilience level. Conclusions: This study highlights the importance of migrant workers in Busan, Korea. To improve their mental health, social support including financial supports and educational programs that foster resilience needed.

• The Journal of Korean Physical Therapy
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• 제20권1호
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• pp.57-65
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• 2008

Purpose: Heat shock proteins (HSPs) are a group of proteins that are activated when cells are exposed to a variety of environmental stresses, such as infection, inflammation, exposure to toxins, starvation, hypoxia, brain injury, or water deprivation. The activation of HSPs by environmental stress plays a key role in signal transduction, including cytoprotection, molecular chaperone, anti-apoptotic effect, and anti-aging effects. However, the precise mechanism for the action of small HSPs, such as HSP27 and mitogen-activated protein kinases (MAPKs: extracellular-regulated protein kinase 1/2 (ERK1/2), p38MAPK, stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), is not completely understood, particularly in application of cell stimulators including platelet-derived growth factor (PDGF), angiotensin II (AngII), tumor necrosis factor $\alpha$ (TNF$\alpha$), and $H_2O_2$. This study examined the relationship between stimulators-induced enzymatic activity of HSP27 and MAPKs from rat smooth and skeletal muscles. Methods: 2-dimensional electrophoresis (2DE) and matrix assisted laser desorption ionizationtime-of-flight/time-of-flight (MALDI-TOF/TOF) analysis were used to identify HSP27 from the intact vascular smooth and skeletal muscles. Three isoforms of HSP27 were detected on silver-stained gels of the whole protein extracts from the rat aortic smooth and skeletal muscle strips. Results: The expression of PDGF, AngII, TNF$\alpha$, and $H_2O_2$-induced activation of HSP27, p38MAPK, ERK1/2, and SAPK/JNK was higher in the smooth muscle cells than the control. SB203580 (30${\mu}$M), a p38MAPK inhibitor, increased the level of HSP27 phosphorylation induced by stimulators in smooth muscle cells. Furthermore, the age-related and starvation-induced activation of HSP27 was higher in skeletal muscle cells (L6 myoblast cell lines) and muscle strips than the control. Conclusion: These results suggest, in part, that the activity of HSP27 and MAPKs affect stressors, such as PDGF, AngII, TNF$\alpha$, $H_2O_2$, and starvation in rat smooth and skeletal muscles. However, more systemic research will be needed into physical therapy, including thermotherapy, electrotherapy, radiotherapy and others.

• 한국산학기술학회논문지
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• 제14권8호
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• pp.3815-3823
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• 2013

본 연구는 소방공무원들의 지각한 현장출동 충격 경험과 외상 후 스트레스가 신체증상 및 대처방식에 미치는 영향을 규명하기 위하여 강원도 소재 소방안전센터에 근무하고 있는 소방공무원 남녀 362명을 대상으로 조사하였다. 수집된 자료는 Windows용 SPSS 19.0과 AMOS 19.0을 사용하여 빈도분석, 타당도와 신뢰도 분석을 위한 요인분석과 Cronbach's ${\alpha}$ 분석, 기술통계와 상관관계를 실시하였고, 가설 검정을 위해 구조방정식 모형을 이용한 분석을 실시하였다. 모든 통계분석은 유의수준은 p<.05로 설정하였다. 결과는 다음과 같다. 첫째, 지각한 현장출동 충격 경험은 외상 후 스트레스에 영향을 미치는 것으로 나타났다. 둘째, 지각한 현장출동 충격 경험이 신체증상에 영향을 미치는 것으로 나타났다. 셋째, 지각한 현장출동 충격 경험은 대처방식에 영향을 미치는 것으로 나타났다. 넷째, 외상 후 스트레스는 신체증상에 영향을 미치는 것으로 나타났다. 다섯째, 외상 후 스트레스는 대처방식에 영향을 미치는 것으로 나타났다. 여섯째, 신체증상은 대처방식에 영향을 미치는 것으로 나타났다. 이러한 결론으로 볼 때 충격적 스트레스를 해소하기 위한 제도적 방안으로 전 세계적으로 검증이 되어 실제 운영되고 있는 위기상항 스트레스 해소법(Critical Incident Stress Debriefing : CISD)을 소방서의 실정에 맞게 도입하여 운영하는 것이 필요할 것이다.

• 한국자동차공학회논문집
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• 제25권3호
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• pp.344-349
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• 2017

Suspension noise from under a passenger car is one of the important factors that impact the perceptual quality for drivers. However, it is difficult to validate this by component level testing in the early stage of development, because suspension noise caused by interaction of the related parts has been found at saleable vehicles late during development or at the manufacturing stage, when many customers have already filed for claims. This study proposed a validation testing under research by the DFSS process that enables reproduction of vehicle level noise by component level testing using a shock absorber with the related parts, such as urethane bumper and top mount. This study also developed a compromised test matrix while analyzing the noise factors through experimental design and analysis of variance to determine what factors can affect noise. Based on this study, we expect that the vehicle level and customer claim can be validated during initial development timing by a more reliable component noise validation test.

• The Korean Journal of Physiology and Pharmacology
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• 제18권5호
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• pp.403-409
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• 2014

The Bis protein is known to be involved in a variety of cellular processes including apoptosis, migration, autophagy as well as protein quality control. Bis expression is induced in response to a number of types of stress, such as heat shock or a proteasome inhibitor via the activation of heat shock factor (HSF)1. We report herein that Bis expression is increased at the transcriptional level in HK-2 kidney tubular cells and A172 glioma cells by exposure to oxidative stress such as $H_2O_2$ treatment and oxygen-glucose deprivation, respectively. The pretreatment of HK-2 cells with N-acetyl cysteine, suppressed Bis induction. Furthermore, HSF1 silencing attenuated Bis expression that was induced by $H_2O_2$, accompanied by increase in reactive oxygen species (ROS) accumulation. Using a series of deletion constructs of the bis gene promoter, two putative heat shock elements located in the proximal region of the bis gene promoter were found to be essential for the constitutive expression is as well as the inducible expression of Bis. Taken together, our results indicate that oxidative stress induces Bis expression at the transcriptional levels via activation of HSF1, which might confer an expansion of antioxidant capacity against pro-oxidant milieu. However, the possible role of the other cis-element in the induction of Bis remains to be determined.