• Title/Summary/Keyword: Challenge Stress

검색결과 183건 처리시간 0.026초

Protective Effects of Acorn (Quercus acutissima CARR.) against IgE-mediated Allergic and Ovalbumin (OVA)-Induced Asthmatic Responses via Inhibition of Oxidative Stress

  • Chung, Mi-Ja;Jo, Hang-Soo;Choi, Ha-Na;Cho, Soo-Muk;Park, Yong-Il
    • Journal of Pharmaceutical Investigation
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    • 제41권6호
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    • pp.355-362
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    • 2011
  • This work was performed to investigate the protective effect of ethanol extract (AEx) from acorn (Quercus acutissima CARR.) against allergic mediated responses in asthma model cells and mice. The AEx inhibited antigen-stimulated cytokine production such as interleukin (IL)-4, IL-13 and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and AEx also inhibited intracellular reactive oxygen species (ROS) generation against IgE-mediated allergic response in rat basophilic leukaemia RBL-2H3 cells. The ovalbumin (OVA)-sensitized mice were orally administered with AEx (100 or 300 mg/kg) and authentic tannic acid (75 mg/kg) every day for 15 days. Increased TNF-${\alpha}$ production by OVA-sensitization/challenge was significantly reduced by administration of AEx. The serum triglyceride levels of asthma mice were significantly reduced after feeding for 15 days with tannic acid or AEx. The mice fed with tannic acid or AEx also exhibited a significant reduction in body weights compared to those of asthma control group. The AEx increased the heme oxygenase (HO)-1 mRNA expression in the asthma model mice and showed DPPH radical scavenging activity. These results indicate that AEx protects against IgEmediated allergic and OVA-induced asthmatic responses via direct and indirect antioxidant activities. Reduced triglyceride and body weights may provide additional protective benefits of AEx on allergic asthma.

Quaternary Tectonic Activities and Seismic Stability of Suryum Fault and Yupchon Fault, SE Korea (수렴단층과 읍천단층의 제4기 활동 및 지진 안정성)

  • Hwang, Sangill;Shin, Jaeryul;Yoon, Soon-Ock
    • Journal of the Korean association of regional geographers
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    • 제18권4호
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    • pp.351-363
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    • 2012
  • Although the Korean peninsula has been considered as a largely aseismic region compared with the surrounding high seismic areas such as North China and Japan, there are more than thirty Quaternary faults reported so far, which are mostly centered in the southeastern peninsula. Structural studies of active faults exposed in Yangnam-myeon of Gyeongju, SE Korea are largely interpreted to post date the late Quaternary, suggesting that the NE-trending reverse faults may result from the active stress regime in the peninsula. The prevailing present-day E-W $S_{Hmax}$ orientations in the peninsula are consistent with the nature of plate forcing stemming from the convergence between the Indo-Australian and Eurasian plates. It is clear that the Quaternary faults have been reactivated, although resolving more elaborate time intervals responsible for a future rupture remains a significant challenge. This study contributes to better assess many of potential seismic hazards in the study area, in particular, in terms of seismic stability for foundation of nuclear power plant.

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Evaluation of Direct Vessel Injection Design With Pressurized Thermal Shock Analysis (가압 열충격해석에 의한 직접용기주입 설계의 평가)

  • Cha, Jong-Hee;Jun, Hyung-Gil
    • Nuclear Engineering and Technology
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    • 제24권1호
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    • pp.86-97
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    • 1992
  • The purpose of this paper is to evaluate the direct vessel injection design from a pressurized thermal shock(PTS) viewpoint for the Combustion Engineering System 80+ A break of the main steam line from zero power and a 0.05 ft$^2$small break loss-of-coolant accident (LOCA) from full power were selected as the potential PTS events. In order to investigate the stratification effects in the reactor downcomer region, the fluid mixing analysis was performed using the COMMIX-IB code for steam line break and using the REMIX code for 0.05 ft$^2$small break LOCA. The stress distributions within the reactor vessel walls experiencing the pressure and the temperature transients were calculated using the OCA-P code for both events. The results of the analysis showed that a small break LOCA without decay heat presented the greatest challenge to the vessel, however, there is no crack initiation through end-of-life of the vessel with consideration of decay heat.

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Post Pelvic Radiotherapy Bony Changes (골반 방사선 치료후의 골 변화와 손상)

  • Huh, Seung-Jae
    • Radiation Oncology Journal
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    • 제27권1호
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    • pp.1-9
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    • 2009
  • There has been recent interest in radiation-induced bone injury in clinical conditions, especially for pelvic insufficiency fracture (PIF). A PIF is caused by the effect of normal or physiological stress on bone with demineralization and decreased elastic resistance. Pelvic radiotherapy (RT) can also contribute to the development of a PIF. A PIF has been regarded as a rare complication with the use of megavoltage equipment. However, recent studies have reported the incidence of PIFs as $8.2{\sim}20%$ after pelvic RT in gynecological patients, an incidence that was higher than previously believed. The importance of understanding a PIF lies in the potential for misdiagnosis as a bony metastasis. If patients complain of pelvic pain after whole-pelvis radiation therapy, the presence of a PIF must be considered in the differential diagnosis. The use of multibeam arrangements and conformal RT to reduce the volume and dose of irradiated pelvic bone can be helpful to minimize the risk of fracture. In addition to a PIF, osteonecrosis and avascular necrosis of the femoral head can develop after radiation therapy. Osteoradionecrosis of the pelvic bone is a clinical diagnostic challenge that must be differentiated from an osseous metastasis. A post-radiation bone sarcoma can result as a long-term sequela of pelvic irradiation for uterine cervical cancer.

Nutritional Metabolomics (영양 대사체학)

  • Hong, Young-Shick
    • Journal of the Korean Society of Food Science and Nutrition
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    • 제43권2호
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    • pp.179-186
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    • 2014
  • Metabolomics is the study of changes in the metabolic status of an organism as a consequence of drug treatment, environmental influences, nutrition, lifestyle, genetic variations, toxic exposure, disease, stress, etc, through global or comprehensive identification and quantification of every single metabolite in a biological system. Since most chronic diseases have been demonstrated to be linked to nutrition, nutritional metabolomics has great potential for improving our understanding of the relationship between disease and nutritional status, nutrient, or diet intake by exploring the metabolic effects of a specific food challenge in a more global manner, and improving individual health. In particular, metabolite profiling of biofluids, such as blood, urine, or feces, together with multivariate statistical analysis provides an effective strategy for monitoring human metabolic responses to dietary interventions and lifestyle habits. Therefore, studies of nutritional metabolomics have recently been performed to investigate nutrition-related metabolic pathways and biomarkers, along with their interactions with several diseases, based on animal-, individual-, and population-based criteria with the goal of achieving personalized health care in the future. This article introduces analytical technologies and their application to determination of nutritional phenotypes and nutrition-related diseases in nutritional metabolomics.

Evaluation of Rare Earths viewed from the Occupational Health (산업보건 측면에서의 희토류 건강영향 평가)

  • Shin, Seo-Ho;Rim, Kyung-Taek;Kim, Jong-Choon
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • 제26권3호
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    • pp.237-252
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    • 2016
  • Objectives: This study was conducted in order to improve the current understanding of rare earths(RE) and to provide supporting data for establishing occupational health policies by reviewing the toxicological data and issues caused by the use of RE compounds in various fields. Methods: To evaluate the potential toxicity of RE from the viewpoint of occupational health, we summarized extensive reviews of relevant articles in the toxicology(animals and cells), occupational health and safety, and epidemiologic literature. Results: Although occupational RE exposure occurs extensively from ore mining and refining to end users in various industrial applications, epidemiologic study has not been performed among workers up to now. Bioaccumulation and adverse effects of RE have also been mentioned in ore mining regions and nearby residences, but safety standards for each process are insufficient. Moreover, because new commercial recycling technology will soon be applied to various industries, regulation and policies are needed for preventing abuse of recycling. In the results of animal toxicity for a few REs(mostly cerium, lanthanum, and gadolinium), toxicities of liver, lung, blood, and the nervous system were identified due to oxidative stress, but study of long-term RE exposure is required. Understanding the dual effect for RE and discovery of biomarkers pose a scientific challenge in further mechanism studies. Conclusions: In the future, additional hazard evaluation based on animal experiments is required, alongside continuous research for developing analytical methods and discovering biomarkers. Finally, RE occupational health and safety management needs to be integrated into the sustainable use of these materials.

Increased Methylation of Interleukin 6 Gene Is Associated with Obesity in Korean Women

  • Na, Yeon Kyung;Hong, Hae Sook;Lee, Won Kee;Kim, Young Hun;Kim, Dong Sun
    • Molecules and Cells
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    • 제38권5호
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    • pp.452-456
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    • 2015
  • Obesity is the fifth leading risk for death globally, and a significant challenge to global health. It is a common, complex, non-malignant disease and develops due to interactions between the genes and the environment. DNA methylation can act as a downstream effector of environmental signals; analysis of this process therefore holds substantial promise for identifying mechanisms through which genetic and environmental factors jointly contribute to disease risk. To assess the effects of excessive weight and obesity on gene-specific methylation levels of promoter regions, we determined the methylation status of four genes involved in inflammation and oxidative stress [interleukin 6 (IL6), tumor necrosis factor ${\alpha}$ ($TNF{\alpha}$), mitochondrial transcription factor A (TFAM), and glucose transport 4 (GLUT4)] in blood cell-derived DNA from healthy women volunteers with a range of body mass indices (BMIs) by methylation-specific PCR. Interestingly, the samples from obese individuals ($BMI{\geq}30kg/m^2$) showed significantly increased hypermethylation for IL6 gene compared to normal weight ($BMI<23kg/m^2$) and overweight sample ($23kg/m^2{\leq}BMI<30kg/m^2$) (P = 0.034 and P = 0.026). However there was no statistically significant difference in promoter methylation of the other 3 genes between each group. These findings suggest that aberrant DNA methylation of IL6 gene promoter may play an important role in the etiology and pathogenesis of obesity and IL6 methylation could be used as molecular biomarker for obesity risk assessment. Further studies are required to elucidate the potential mechanisms underlying this relationship.

Review of Rice Quality under Various Growth and Storage Conditions and its Evaluation using Spectroscopic Technology

  • Joshi, Ritu;Mo, Changyeun;Lee, Wang-Hee;Lee, Seung Hyun;Cho, Byoung-Kwan
    • Journal of Biosystems Engineering
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    • 제40권2호
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    • pp.124-136
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    • 2015
  • Purpose: Grain quality is a general concept that covers many characteristics, ranging from physical to biochemical and physiochemical properties. Rice aging during storage is currently a challenge in the rice industry, and is a complicated process involving changes in all of the above properties. Spectroscopic techniques can be used to obtain information on the quality of rice samples in a non-destructive manner. Methods: The objective of this review was to highlight the factors that contribute to rice quality and aging, and to describe various spectroscopic modalities, particularly vibrational and hyperspectral imaging, for the assessment of rice quality. Results: Starch and protein are the main components of the rice endosperm, and are therefore key factors contributing to eating and cooking quality. While the overall starch, protein, and lipid content in the rice grain remains essentially unchanged during storage, structural changes do occur. These changes affect pasting and gel properties, and ultimately the flavor of cooked rice. In addition, grain quality is significantly affected by growing and environmental conditions, such as water availability, temperature, fertilizer application, and salinity stress. These properties can be evaluated using spectroscopic techniques, and rice samples can be discriminated by using multivariate statistical analysis methods. Conclusion: Hyperspectral imaging and vibrational spectroscopy techniques have good potential for determining rice quality properties in a non-invasive manner, i.e., not requiring the introduction of instruments into the rice grain.

Molecular Genetic Characterization and Analysis of Glucocorticoid Receptor Expression in the Big-belly Seahorse Hippocampus abdominalis (빅벨리해마(Hippocampus abdominalis) 글루코코르티코이드 수용체의 분자 유전학적 동정과 발현 분석)

  • Jo, Eunyoung;Oh, Minyoung;Lee, Sukkung;Qiang, Wan;Lee, Jehee
    • Korean Journal of Fisheries and Aquatic Sciences
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    • 제48권3호
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    • pp.346-353
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    • 2015
  • Glucocorticoids (GCs) are steroid hormones regulated through responses to stress to maintain diverse metabolic and homeostatic functions. GCs act on the glucocorticoid receptor (GR), a member of the nuclear receptor family. This study identified and characterized the GR gene from the big-belly seahorse Hippocampus abdominalis designating it HaGR. The open reading frame of the HaGR cDNA was 2,346 bp in length, encoding a 782-amino-acid polypeptide with a theoretical isoelectric point of 6.26 and predicted molecular mass of 86.8 kDa. Nuclear receptors share a common structural organization, comprising an N-terminal transactivation domain, DNA-binding domain, and C-terminal ligand-binding domain. The tissue-specific mRNA expression profile of HaGR was analyzed in healthy seahorses using a qPCR technique. HaGR mRNA was expressed ubiquitously in all of the tissues examined, with the highest expression levels in kidney, intestine, stomach, and gill tissues. The mRNA expression in response to immune challenge with lipopolysaccharide (LPS), polyinosinic:polycytidylic acid (poly I:C), Edwardsiella tarda, and Streptococcus iniae revealed that it is inducible in response to pathogen infection. These results suggest that HaGR is involved in the immune response of the big-belly seahorse.

Rethinking Clusters : Towards a More Open and Evolutionary Approach (전통적 산업집적지의 변화과정과 경제적 성과)

  • Mackinnon, Danny
    • Journal of the Korean Academic Society of Industrial Cluster
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    • 제2권1호
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    • pp.14-27
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    • 2008
  • Ousters have become a key focus of interest and analysis over the last decade or so, informed by the work of the Harvard business economist Michael Porter. Recent research, however, suggests that the classic Porterian conception of clusters needs to be rethought. In particular, the idea that clusters are geogaphically bounded and integrated units whose primary link to the outside world is through the export of goods and services to global markets is highly Questionable, if not untenable. Relational approaches to clusters and regional development stress the importance of the wider networks and 'pipelines' through which knowledge is exchanged with key partners and collaborators located outside of the particular cluster in question. Rather than the main external links being those between leading firms and global markets, firms may engage in a range of global relations with collaborators and suppliers. This paper address the challenge of rethinking clusters in the light of the recent emphasis on global networks md connections, drawing on experience from m old industrial region in Western Europe Scotland. In assessing cluster experiences and initiatives in Scotland, I examine the development of the oil and gas and electronics clusters. In conclusion, I suggest that cluster initiatives me only likely to generate lasting benefits for the region in question if there is significant local ownership md control of key industries and clusters.

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