• Title/Summary/Keyword: Life-stress

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Fatigue Field Test of Variable Message Sign Structure and Evaluation of AASHTO Specifications (가변정보판이 설치된 지주구조물에 대한 피로 시험 및 AASHTO설계기준 적용성 평가)

  • Park, Jong Sup
    • Journal of Korean Society of Steel Construction
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    • v.18 no.1
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    • pp.11-22
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    • 2006
  • Message Signs (VMS) structures offer an increase in traffic safety through their ability to relay massages to motorists for warnings of hazards ahead, traffic congestion, accidents, and lane closings. The geometry of these signs sometimes results in the significant cyclic loading of the supports structure due to wind gusts, which can result from passing trucks or from natural wind. This study presents the results of analytical and experimental investigations of VMS structures. The commercially available softwareGTSTRUDL (2003) was used to perform space-frame structural analyses of these welded tubular structures. Fatigue evaluations were performed using stress ranges from field measurements and from structural analyses. Based on the results of the structural analyses that were conducted, where fatigue design loadings that had been derived from AASHTO Specifications for Structural Supports for Highway Signs, Luminaries, and Traffic Signals (2001) were used, the structures that had been studied were found not to have infinite fatigue life. According to the limited measurements that were made in this study, the fatigue design loadings derived from AASHTO Specifications (2001) appear to be conservative, but they are not overly conservative. The results of this study should be used to make a reasonable design of VMS structures, and to maintain their standards.

Neuroprotective Effects of Pinelliae Rhizoma Water-Extract by Suppression of Reactive Oxygen Species and Mitochondrial Membrane Potential Loss in a Hypoxic Model of Cultured Rat Cortical Cells. (배양대뇌신경세포 저산소증모델에서 유해산소생성억제 및 사립체막전위 소실방지에 의한 반하(半夏)의 신경세포사 억제 효능)

  • Kwon, Gun-Rok;Moon, Il-Soo;Lee, Won-Chul
    • Journal of Life Science
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    • v.19 no.5
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    • pp.598-606
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    • 2009
  • Oxidative stress by free radicals is a major cause of neuronal cell death. Excitotoxicity in hypoxia/ischemia causes an increase in reactive oxygen species (ROS) and a loss of mitochondrial membrane potential (MMP), resulting in dysfunction of the mitochondria and cell death. Pinelliae Rhizoma (PR) is a traditional medicine for incipient stroke. We investigated the effects of PR Water-Extract on the modulation of ROS and MMP in a hypoxic model using cultured rat cortical cells. PR Water-Extract was added to the culture medium at various concentrations (0.25${\sim}$5, 5.0 ${\mu}g/ml$) on day in vitro 12(DIV12), given a hypoxic shock (2% $O_2$/5% $CO_2$, $37^{\circ}C$, 3 hr), and cell viability was assessed on DIV15 by Lactate Dehydrogenase Assay (LDH assays). PR Water-Extract showed a statistically significant effect on neuroprotection (10${\sim}$15% increase in viability; p<0.01) at 1.0 and 2.5 ${\mu}g/ml$ in normoxia and hypoxia. Measurement of ROS production by $H_2DCF-DA$ stainings showed that PR Water-Extract efficiently reduced the number and intensity of ROS-producing neurons, especially at 1 hr post shock and DIV15. When MMP was measured by JC-1 stainings, PR Water-Extract efficiently maintained high-energy charged mitochondria. These results indicate that PR Water-Extract protects neurons in hypoxia by preventing ROS production and preserving the cellular energy level.

The Relationship between the Urinary Arsenic and 8-Hydroxydeoxyguanosine Levels in Women of Abandoned Mine Area (일부 폐금속광산 지역 거주 여성의 요중 비소와 8-hydroxydeoxyguanosine 농도 사이의 관련성)

  • Choi, Young-Sook;Eom, Sang-Yong;Choi, Byoung-Sun;Park, Jung-Duk;Kim, Yong-Dae;Kim, Heon
    • Journal of Life Science
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    • v.20 no.4
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    • pp.618-622
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    • 2010
  • This study examines the relationship between urinary arsenic concentration and urinary 8-hydroxydeoxyguanosine (8-OHdG) concentrations, an index of oxidative DNA damage, among women who live near abandoned metal mines. The sample consisted of 165 residents living near two abandoned metal mines located in Chungbuk Province. Demographic characteristics as well as environmental factors relevant to arsenic exposure were collected through interviews, and urinary arsenic concentrations and urinary 8-OHdG concentrations of the research subjects were measured. The collected data were subsequently analyzed using the statistics program SPSS 12.0. The geometric average of urinary arsenic concentrations among the research subjects was $5.65\;{\mu}g/g$ creatinine. In a correlation analysis between urinary arsenic and 8-OHdG concentrations, the correlation coefficient was significant (p<0.001) at 0.399. This study suggests that urinary 8-OHdG concentrations may be a DNA damage marker for chronic arsenic exposure in women.

Rutin Ameliorates Neutrophilic Oxidative Stress-Induced Acute Lung Injury by Intratracheal IL-1 Insufflation in Rats (Interleukin-1으로 유도된 급성폐손상에서 rutin의 효과)

  • Kwon, Sung-Chul;Park, Yoon-Yub;Lee, Young-Man
    • Journal of Life Science
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    • v.20 no.4
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    • pp.474-480
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    • 2010
  • Rutin, a group II phospholipase $A_2$ ($PLA_2$) inhibitor, was tested on interleukin-1 (IL-1) induced acute lung injury (ALI) in male Sprague-Dawley rats. Rutin did not alter the increased lung myeloperoxidase activity by IL-1. However, the number of neutrophils in bronchoalveolar lavage fluid (BALF) and IL-1 induced lung leak were decreased by rutin (p<0.001). Simultaneously, rutin decreased lung $PLA_2$ activity, which was increased by IL-1 (p<0.001). The reduction of neutrophilic respiratory burst by the inhibition of $PLA_2$ was confirmed by group II $PLA_2$ inhibitors such as rutin, manoalide and scalaradial. The increased level of cytokine-induced neutrophilic chemoattractant (CINC) in BALF by IL-1 was not affected by rutin. Ultrastructural changes of ALI and increased generation of free radicals in the lung by IL-1 were found, and rutin ameliorated these pathological findings. Taken together, rutin seems to be effective in decreasing IL-1 induced ALI through inhibition of group II $PLA_2$.

Pre-Exercise Protective Effects Against Renal Ischemic Reperfusion Injury in Hsp 70.1 Knockout Mice (Hsp70.1유전자결핍된 마우스에서 허혈 재관류 신장손상에 대한 전처치 운동의 보호효과)

  • Lee, Jin;Kim, Won-Kyu
    • Journal of Life Science
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    • v.20 no.4
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    • pp.555-560
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    • 2010
  • The objective of this study was to investigate levels of serum creatinine, CuSOD and MnSOD protein expression in the kidney after renal ischemic reperfusion with pre-exercise using heat shock protein 70.1 in knock-out mice (KO). The C57/BL6 strain (Wild type: WT) and KO were divided into 4 groups as follows: Sham control group (Sham), pre-exercise group (Ex), pre-exercise +ischemia group (Ex+IR), and ischemia group (IR). CuSOD and MnSOD expression were significantly decreased (p<0.01, p<0.05) and blood creatinine concentration was significantly increased (p<0.01) in the IR group of KO. In contrast, CuSOD and MnSOD expression in the Ex+IR group of KO were higher than the IR group, while creatinine concentration was significantly lower. These results suggest that Hsp70 is directly correlated to renal ischemic reperfusion injury. Pre-exercise in renal ischemia might prevent or inhibit positive oxidative stress inhibitory effects by increasing anti-oxidative enzymes (CuSOD, MnSOD) within the kidney and improve to prevent renal function. Thus, pre-exercise may have a protective role against renal injury after renal ischemia.

Prostate Apoptosis Response-4 (Par-4) as a Cancer Therapeutic Target (암 치료 표적으로써 prostate apoptosis response-4 (Par-4))

  • Woo, Seon Min;Kwon, Taeg Kyu
    • Journal of Life Science
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    • v.25 no.8
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    • pp.947-952
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    • 2015
  • Prostate apoptosis response-4 (Par-4) was originally identified in androgen-independent prostate cancer cells undergoing apoptosis. Par-4 is ubiquitously expressed in normal cells and tissues, but it is downregulated in several types of cancers. Par-4 is a 38 kDa tumor suppressor protein encoded by the PARW gene. Par-4 promotes apoptosis in a variety of cancerous cells, but not in normal cells. In this review, we focused on the structure, expression and function of Par-4 in apoptotic signaling pathway. Functional domains of Par-4 include two nuclear localization sequences (NLS), a leucine zipper (LZ) domain, a nuclear export sequence (NES) and selective for apoptosis in cancer cell (SAC) domain. Many studies have underlined the importance of Par-4 in preventing cancer development. The activity of Par-4 is differently regulated by localization of intracellular and extracellular Par-4. Intracellular Par-4 inhibits Akt- and NF-κB-mediated cell survival pathways and downregulates Bcl-2 expression. Extracellular Par-4 activates the extrinsic apoptotic pathway by binding to cell surface receptor GRP78, a stress response protein that is in the endoplasmic reticulum (ER). Endogenous Par-4 sensitizes cancer cells to various apoptotic stimuli, while exogenous Par-4 enhances SAC domain-dependent apoptosis in cancer cells, but not normal cells. Therefore, Par-4 is an attractive target for cancer therapy.

Effect of Fruit Extract of Prunus mume on the Scavenging Activity of Reactive Oxygen Species and Melanin Production in B16F1 Cells (매실추출물이 활성산소종 소거효과와 B16F1 세포에서 멜라닌 생성에 미치는 영향)

  • Park, Hyeong-Joon;Kim, Moon-Moo;Oh, Yung-Hee
    • Journal of Life Science
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    • v.22 no.7
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    • pp.936-942
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    • 2012
  • Prunus mume has been traditionally used as a medicinal food in Korea, Japan, and China. In particular, this fruit has been reported to have beneficial biological effects on gastritis and gastric ulcers. However, its action in relation to skin whitening has remained unclear. Accordingly, the effects of fruit extract of P. mume related to antioxidation and skin whitening were examined in this study. First, using the MTT assay, it was observed that fruit extract of P. mume below 0.1% has no cytotoxicity in B16-F1 cells as a result of cell viability. Second, the direct scavenging effects and the reducing power of the fruit extract of P. mume were evaluated in vitro on DPPH radicals, hydrogen peroxide, and superoxide. It exhibited high reducing power and scavenging activity on the aforementioned reactive oxygen species. Furthermore, we found that its protective effect against genomic DNA damage related to oxidative stress was increased in a dose-dependent manner. In addition, the fruit extract of P. mume had an inhibitory effect on melanin production induced by L-dopa. In addition, it reduced the expression level of NRF-2, SOD-1, and SOD-2 related to antioxidation in western blot analysis. These results suggest that fruit extract of P. mume could exert a whitening effect through inhibition of melanin production by its antioxidant effect.

Effect of Reverse Feeding on the Reproductive System in Male Rats

  • Jeon, Eun-Young;Lee, Sung-Ho
    • Development and Reproduction
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    • v.16 no.3
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    • pp.227-233
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    • 2012
  • Circadian timing system plays a major role in a wide range of reproductive function. However it is plausible idea that other environmental and/or internal cue might be simultaneously participated in the optimal regulation of reproductive system. In the present study we extended the reverse feeding (RF) time regimen up to 8 weeks, then measured the general and reproductive indices of the animals. The animals of ad libitum feeding group (Control, CON) have free access to food for 4, 6 and 8 weeks, respectively. The day feeding animals (reverse feeding, RF group) have restricted access to food during daytime (09:00-18:00) for 4, 6 and 8 weeks, respectively. When the feeding schedules were over, key indices were measured. After 4 weeks and 8 weeks of feeding, body weights of animals were not significantly different. However, body weights of 6 weeks RF animals were significantly smaller than those of control animals (CON : RF = $333.46{\pm}12.71$ g : $289.91{\pm}8.31$ g, p<0.01). The blood glucose levels of 4 weeks RF animals were significantly decreased compared to the levels of control animals (CON : RF = $161.4{\pm}2.7$ mg/dL : $176.7{\pm}5$ mg/dL, p<0.01) while the levels of 6 weeks RF and 8 weeks RF animals were not different form those of control animals. Reproductive and non-reproductive tissue weights from 6 weeks RF group were significantly lowered than those from CON group (testis, CON : RF = $1.4714{\pm}0.0174$ g : $1.3724{\pm}0.0168$ g, p<0.001; epididymis, CON : RF = $0.3574{\pm}0.0059$ g : $0.3243{\pm}0.0068$ g, p<0.001; seminal vesicle, CON : RF = $0.1655{\pm}0.0068$ g : $0.1328{\pm}0.0054$ g, p<0.001; prostate, CON : RF = $0.3350{\pm}0.0231$ g : $0.2528{\pm}0.0143$ g, p<0.01). After 4 weeks and 8 weeks of reverse feeding, sperm counts in RF animals were markedly reduced than those in control animals[CON 4W : RF 4W = $121.17{\pm}9.96\;({\times}10^6)$ : $50.86{\pm}9\;({\times}10^6)$, p<0.001; CON 8W : RF 8W= $138.69{\pm}9.8\;({\times}10^6)$ : $108.94{\pm}4.22\;({\times}10^6)$, p<0.001]. Present study indicates that RF may induce an adaptable metabolic stress and cause impairment of androgen-dependent reproductive tissues. On-going longitudinal studies will allow a better understanding of the how does mealtime shift affect the reproductive function and exact nature of adaptation.

Acetycholinesterase Inhibiting Effect and Free Radical Scavenging Effect of Soybean(Glycine max) and Yak-Kong(Rhynchosia nolubilis) (대두와 약콩의 Acetylcholinesterase 활성 억제효과와 항산화 효과)

  • 강순아;한진아
    • Journal of the East Asian Society of Dietary Life
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    • v.14 no.1
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    • pp.64-69
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    • 2004
  • The deficiency of the neurotransmitter acetylcholine(ACh) is responsible for the initiation of Alzheimer's disease. In addition, there is a simple evidence that oxidative stress significantly increases in persons with Parkinson's disease compared to age-matched healthy persons. Therefore, the objective of the study was to investigate the neurodegeneration inhibitory effect of soybean(Glycine Max) and Yak-Kong(Rhynchosia Nolubilis) by measuring the degree of inhibiting Acetylcholinesterase (AChE) catabolizing the ACh and the free radical scavenger effect in vitro. AChE was measured by the minor modified Ellman assay. Free radical scavenging activity was measured using l-diphenyl-2-picrylhydrazyl (DPPH). First, the MeOH extracts of Soybean and Yak-Kong showed the AChE inhibiting activity of 62.0$\pm$2.43% and 65.0$\pm$3.29% at the 5 mg/$m\ell$ concentration. The 50% inhibitory concentration ($IC_{50}$/) of AChE was 1.96 and 1.31 mg/$m\ell$ in the MeOH extracts of soybean and Yak-Kong. Second, the MeOH extracts of soybean and Yak-Kong showed the free radical scavenger activity of 23.1$\pm$4.26% and 80.7$\pm$4.61% at the 5 mg/$m\ell$. IC50 of free radical scavenger activity in Soybean and Yak-Kong was 13.00 and 1.41 mg/$m\ell$ in MeOH extracts and was 5.95 and 2.74 mg/$m\ell$ in hot-water extracts, respectively. In this study, the extracts of Soybean and Yak-Kong showed powerful effects in the AChE inhibition and free radical scavenging. The extracts of Soybean and Yak-Kong were expected to prevent the many neurodegenerative diseases.

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Studies on the Grain Quality Characteristics of Rice Transgenic Lines (벼 형질전환계통의 미질특성에 대한 고찰)

  • Jeong, Jong-Min;Jeung, Ji-Ung;Kang, Kyung-Ho;Lee, Sang-Bok;Mo, Young-Jun;Kim, Chung-Kon;Kim, Kyung-Min;Sohn, Jae-Keun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.58 no.2
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    • pp.203-211
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    • 2013
  • Selected 11 rice transgenic lines, through preliminary yield trials on 32 lines, were evaluated on important agronomic traits as well as grain quality by conducting replicated yield trials having three replication plots. Japonica recipients, Nipponbare, Nagdongbyeo, and Dongjinbyeo, were the recipients of 7 transformed genes, which were putatively related with high yield, abiotic stress tolerance, and disease resistance. To estimate the degrees of deviations from the wild types, 11 traits of transgenic lines, relating with grain quality were evaluated and subjected to multivariate analyses. Principal coordinate and clustering analyses did not support collection manners of transgenic lines in terms of the genes transformed as well as the genetic background. Meanwhile, some transgenic lines would be acceptable due to their over-all performances were similar to their wild types, it was hardly possible to declare any transgenic line, which adhered closely to the commercial profits of wild type. Thereby, with considerations on the demanding resources in establishing rice transgenic lines having market competitiveness, it was speculated that proper application of breeding strategies would be crucial factor for the efficiency of developing prospective rice transgenic lines.