• Title/Summary/Keyword: Time-dependent

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Temperature-dependent Development and Its Model of the Greenbug, Schizaphis graminum (Rondani) (Homoptera: Aphididae) (보리두갈래진딧물 [Schizaphis graminum (Rondani)]의 온도발육과 발육모형)

  • Lee, Jang-Ho;Kim, Tae-Heung;Kim, Ji-Soo;Hwangn, Chang-Yeon;Lee, Sang-Guei
    • Korean journal of applied entomology
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    • v.46 no.2
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    • pp.213-219
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    • 2007
  • The development of Schizaphis graminum (Rondani) was studied at various constant temperatures ranging from 15 to $32.5^{\circ}C$, with $65{\pm}5%$ RH, and a photoperiod of 16L:8D. Mortality of the $1_{st}-2_{nd}\;and\;the\;3_{rd}-4_{th}$ stage nymphs were similar at most temperature ranges while at high temperature of $32.5^{\circ}C$, more $3_{rd}-4_{th}$ stage individuals died. The total developmental time ranged from 13.8 days at $15^{\circ}C$ to 4.9 days at $30.0^{\circ}C$ suggesting that the higher the temperature, the faster the development. However, at higher end temperature of $32.5^{\circ}C$ the development took 6.4 days. The lower developmental threshold temperature and effective accumulative temperatures for the total immature stage were $6.8^{\circ}C$ and 105.9 day-degrees, respectively and the nonlinear shape of temperature related development was well described by the modified Sharpe and DeMichele model. The normalized cumulative frequency distributions of developmental period for each life stage were fitted to the three-parameter Weibull function. The attendance of shortened developmental times was apparent with $1_{st}-2_{nd}\;nymph,\;3_{rd}-4_{th}$ nymph, and total nymph stages in descending order. The coefficient of determination $r^2$ ranged between 0.80 and 0.87.

Compound K (CK) Rich Fractions from Korean Red Ginseng Inhibit Toll-like Receptor (TLR) 4- or TLR9-mediated Mitogen-activated Protein Kinases Activation and Pro-inflammatory Responses in Murine Macrophages (고려홍삼으로부터 분리한 compound K 함유분획에 의한 대식세포의 toll-like receptor-의존성 신호전달로 활성조절 분석)

  • Yang, Chul-Su;Ko, Sung-Ryong;Cho, Byung-Goo;Lee, Ji-Yeon;Kim, Ki-Hye;Shin, Dong-Min;Yuk, Jae-Min;Sohn, Hyun-Joo;Kim, Young-Sook;Wee, Jae-Joon;Do, Jae-Ho;Jo, Eun-Kyeong
    • Journal of Ginseng Research
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    • v.31 no.4
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    • pp.181-190
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    • 2007
  • Compound K (CK), a protopanaxadiol ginsenoside metabolite, was previously shown to have immunomodulatory effects. In this study, we isolated the CK rich fractions (CKRF) from Korean Red Ginseng and investigated the regulation of CKRF-mediated inflammatory signaling during Toll-like receptor (TLR)-mediated cellular activation. Among various TLR ligands, CKRF considerably abrogated TLR4- or TLR9-induced inflammatory signaling. Both LPS and CpG-containing oligodeoxynucleotides (CpG-ODN) stimulation rapidly activates mitogen-activated protein kinases [MAPKs; extracellular signal-regulated kinases 1/2 and p38], NF-${\kappa}B$, and expression of pro-inflammatory cytokines tumor necrosis factor-${\alpha}$, and interleukin-6 in murine bone marrow-derived macrophages (BMDMs) in a time- and dose-dependent manner. Of interest, pre-treatment of CKRF in either LPS/TLR4- or CpG-ODN/TLR9-stimulated macrophages substantially attenuated the LPS-induced inflammatory cytokine production and mRNA expressions, as well as MAPK and NF-${\kappa}B$ activation. To our knowledge, this is the first description of the inhibitory roles for CKRF in TLR4- or TLR9-associated signaling in BMDMs. Collectively, these results demonstrate that CKRF specifically modulates distinct TLR4 and TLR9-mediated inflammatory responses, and further studies are urgently needed for their in vivo roles for potential therapeutic uses, such as in systemic inflammatory syndromes.

Quality characteristics of farm-made brown rice vinegar via traditional static fermentation (전통정치배양에 의한 농가형 현미식초의 품질특성)

  • Baek, Chang Ho;Jeong, Da-Hee;Baek, Seong Yeol;Choi, Ji-Ho;Park, Hye-Young;Choi, Han Seok;Jeong, Seok-Tae;Kim, Jae Hyun;Jeong, Yong-Jin;Kwon, Joong-Ho;Yeo, Soo-Hwan
    • Food Science and Preservation
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    • v.20 no.4
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    • pp.564-572
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    • 2013
  • We investigated the quality characteristics of brewing brown rice vinegar through a traditional static fermentation process. Accordingly, we decided to compare the physicochemical characteristics of brewing vinegar at different temperatures and filtration methods. In four to five weeks' time, the acetic acid fermentation exhibited the highest titratable acidity and then it eventually decreased. The titratable acidity was affected by the filtration method. It was revealed that the titratable acidity was higher in the forced filtration than the traditional filtration method. Various organic acids were detected in order to initialize the fermentation stage and as the fermentation progressed, only the acetic acid could be detected. The total free amino acid content was higher at a temperature of $30^{\circ}C$ than at $20^{\circ}C$. Moreover, the free amino acid content was dependent on the acetate content during the acetic fermentation process. The main bioactive substance of the ${\gamma}$-aminobutyric acid content was more than twice at a fermentation temperature of $30^{\circ}C$ compared to the fermentation temperature of $20^{\circ}C$. Furthermore, the total amino acid and essential amino acid content at a temperature of $30^{\circ}C$ was excellent. The quality of the brown rice vinegar via forced filtration method at a temperature of $30^{\circ}C$ was the most excellent. Based on these results, the fermentation temperature and the use of nuruks (fermenting agent) affected the quality of the brown rice vinegar, and an appropriate method to consider its purpose is required.

Temperature-dependent Development Model of the Striped Fruit Fly, Bactrocera scutellata (Hendel)(Diptera: Tephritidae) (호박꽃과실파리 온도 발육모형)

  • Jeon, Sung-Wook;Cho, Myoung-Rae;Kim, Yang-Pyo;Lee, Sang-Guei;Kim, So-Hyung;Yu, Jin;Lee, Jong-Jin;Hwang, Chang-Yeon
    • Korean journal of applied entomology
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    • v.50 no.4
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    • pp.373-378
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    • 2011
  • The striped fruit fly, Bactrocera scutellata, damages pumpkin and other cucurbitaceous plants. The developmental period of each stage was measured at seven constant temperatures (15, 18, 21, 24, 27, 30, and $33{\pm}1.0^{\circ}C$). The developmental time of eggs ranged from 4.2 days at $15^{\circ}C$ to 0.9 days at $33^{\circ}C$. The developmental period of larvae was 4.2 days at $15^{\circ}C$, and slowed in temperatures above $27^{\circ}C$. The developmental period of pupa was 21.5 days at $15^{\circ}C$ and 7.6 days at $33^{\circ}C$. The mortality of eggs was 17.1% at $15^{\circ}C$ and 22.9% at $33^{\circ}C$, Larval mortalities (1st, 2nd, 3rd) were 24.1, 27.3 and 18.2%, respectively, at $15^{\circ}C$, Pupal mortalities were 18.2% at $15^{\circ}C$ and 23.1% at $33^{\circ}C$. The relationship between developmental rate and temperature fit both a linear model and a nonlinear model. The lower threshold temperatures of eggs, larvae, and pupae were 12.5, 10.7, and $6.3^{\circ}C$, respectively, and threshold temperature of the total immature period was $8.5^{\circ}C$. The thermal constants required to complete the egg, larval, and pupal stages were 33.2, 118.3, and 181.2 DD, respectively. The distribution of each development stages was described by a 3-parameter Weibull function.

The Effect of the Participative Leadership on Creative Behavior - Focusing on Unidimensional and Multidimensional Mediating Effects of Psychological Empowerment - (참여적 리더십이 창의적 행동에 미치는 영향 - 심리적 임파워먼트의 단일차원과 다차원 매개효과를 중심으로 -)

  • Tak, Je-Woon;Shin, Je-Goo
    • Management & Information Systems Review
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    • v.36 no.5
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    • pp.61-83
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    • 2017
  • The purpose of this study is to investigate the mediating effects of psychological empowerment between participative leadership and creative behavior. Especially, it aims to analyze the unidimension and multidimension of psychological empowerment in an integrated manner, and to suggest effective practice of participative leadership together with theoretical and methodological implications. In this study, the dependent variable was measured separately with time lag as a method to solve the common method bias that can be shown by the self-report type survey method, and positive emotions and negative emotions expressing emotional states in job situations were employed as control variables along with rank. A total of 283 questionnaires were collected from employees who work for companies in various industries with more than 300 domestic employees. SPSS PROCESS macro program('model 4') was used for statistical analysis. Results, First, the full mediation effect of psychological empowerment(unidimension) was confirmed in the relationship between participative leadership and creative behavior. Second, the analysis of the multidimension of psychological empowerment revealed the full mediating effect of meaning, self-determination, and impact, and the mediating effect of competence was not significant. Third, as a result of comparing the mediating effects of unidimension of psychological empowerment and the mediating effects of multidimension, the magnitude of mediating effect of unidimension was found to be much greater than mediating effect of multidimension. And The magnitudes of the three multidimensional mediating effects were similar. This is a case in which the motivational model of participative leadership revealed in the overseas study is proven in the domestic management environment and is significant in that it is the basis of future research. Based on the results of the empirical studies, the implications and limitations of the study and future research directions are presented.

A Long-term Follow up Study on Pulmonary Function after Lobectomy and Pneumonectomy (폐절제술 후 폐환기능의 변화에 대한 장기 추적관찰)

  • Lee, Yi-Hyeong;Kim, Se-Kyu;Chang, Joon;Chung, Kyung-Young;Ahn, Chul-Min;Kim, Sung-Kyu;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.6
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    • pp.638-645
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    • 1993
  • Objectives: The functional effects of pulmonary resection are dependent on the preexisting function of resected and remaining tissue as well as on the compensatory potential of the remaining tissue. Nowadays, large pulmonary resections are usually applied to lung cancer patients often already compromised by chronic lung disease. It is important to evaluate the pulmonary reserve after lung resection preoperatively in the decision of operability and extent of resection. The aim of this study was to evaluate the changes of pulmonary function after pulmonary resection. Methods: 8 lobectomized and 8 pneumonectomized patients were evaluated. The pulmonary function test was performed preoperatively and in immediate postoperative period and thereafter to 5 years at 3 months interval. Results: 1) The pulmonary function 1 week after operation was significantly low compared with predicted values in, lobectomy and pneumonectomy groups(p<0.05), and improved closely to their predicted values 3 months after operation. 2) The FVC was maintained above predicted value at 6-24 months and similar to predicted value thereafter in lobectomy group. In pneumonectomy group, the FVC maintained similar to predicted value at 6-36 months and improved above its predicted value thereafter. 3) The FEV1 was maintained similar to their predicted values from 6 months to 5 years after operation in both groups. 4) The FEV1/FVC did not change in the course of time in both groups. 5) The FEF25-75% was maintained similar to predicted value at 6-60 months after operation in lobectomy group, but it decreased under predicted value after 1 year in pneumonectomy group. 6) The MVV was maintained similar to predicted value at 6-24 months and decrease thereafter in lobectomy group. In pneumonectomy group, the MVV was maintained at 6-60 months after operation. 7) The differeces in the pulmonary function(FVC, FEV1, FEF25-75%, MVV) between two groups were seen only at 6 months after operation(p<0.05). Conclusion: The pulmonary function was markedly decreased immediately after operation, improved similar to predicted value at 1-3 months, highest at 6 months, and maintained similar to the predicted value to 5 years after pulmonary resection. The difference in the pulmonary function between two groups was the most at 6 months after operation.

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Processed Panax ginseng, sun ginseng, inhibits the differentiation and proliferation of 3T3-L1 preadipocytes and fat accumulation in Caenorhabditis elegans

  • Lee, Hyejin;Kim, Jinhee;Park, Jun Yeon;Kang, Ki Sung;Park, Joeng Hill;Hwang, Gwi Seo
    • Journal of Ginseng Research
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    • v.41 no.3
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    • pp.257-267
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    • 2017
  • Background: Heat-processed ginseng, sun ginseng (SG), has been reported to have improved therapeutic properties compared with raw forms, such as increased antidiabetic, anti-inflammatory, and antihyperglycemic effects. The aim of this study was to investigate the antiobesity effects of SG through the suppression of cell differentiation and proliferation of mouse 3T3-L1 preadipocyte cells and the lipid accumulation in Caenorhabditis elegans. Methods: To investigate the effect of SG on adipocyte differentiation, levels of stained intracellular lipid droplets were quantified by measuring the oil red O signal in the lipid extracts of cells on differentiation Day 7. To study the effect of SG on fat accumulation in C. elegans, L4 stage worms were cultured on an Escherichia coli OP50 diet supplemented with $10{\mu}g/mL$ of SG, followed by Nile red staining. To determine the effect of SG on gene expression of lipid and glucose metabolism-regulation molecules, messenger RNA (mRNA) levels of genes were analyzed by real-time reverse transcription-polymerase chain reaction analysis. In addition, the phosphorylation of Akt was examined by Western blotting. Results: SG suppressed the differentiation of 3T3-L1 cells stimulated by a mixture of 3-isobutyl-1-methylxanthine, dexamethasone, and insulin (MDI), and inhibited the proliferation of adipocytes during differentiation. Treatment of C. elegans with SG showed reductions in lipid accumulation by Nile red staining, thus directly demonstrating an antiobesity effect for SG. Furthermore, SG treatment down-regulated mRNA and protein expression levels of peroxisome proliferator-activated receptor subtype ${\gamma}$ ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein-alpha ($C/EBP{\alpha}$) and decreased the mRNA level of sterol regulatory element-binding protein 1c in MDI-treated adipocytes in a dose-dependent manner. In differentiated 3T3-L1 cells, mRNA expression levels of lipid metabolism-regulating factors, such as amplifying mouse fatty acid-binding protein 2, leptin, lipoprotein lipase, fatty acid transporter protein 1, fatty acid synthase, and 3-hydroxy-3-methylglutaryl coenzyme A reductase, were increased, whereas that of the lipolytic enzyme carnitine palmitoyltransferase-1 was decreased. Our data demonstrate that SG inversely regulated the expression of these genes in differentiated adipocytes. SG induced increases in the mRNA expression of glycolytic enzymes such as glucokinase and pyruvate kinase, and a decrease in the mRNA level of the glycogenic enzyme phosphoenol pyruvate carboxylase. In addition, mRNA levels of the glucose transporters GLUT1, GLUT4, and insulin receptor substrate-1 were elevated by MDI stimulation, whereas SG dose-dependently inhibited the expression of these genes in differentiated adipocytes. SG also inhibited the phosphorylation of Akt (Ser473) at an early phase of MDI stimulation. Intracellular nitric oxide (NO) production and endothelial nitric oxide synthase mRNA levels were markedly decreased by MDI stimulation and recovered by SG treatment of adipocytes. Conclusion: Our results suggest that SG effectively inhibits adipocyte proliferation and differentiation through the downregulation of $PPAR{\gamma}$ and $C/EBP{\alpha}$, by suppressing Akt (Ser473) phosphorylation and enhancing NO production. These results provide strong evidence to support the development of SG for antiobesity treatment.

Effect of Ondansetron Alone and Combination of Naltrexone and Ondansetron on Alcohol Intake in C57BL/6 Mice (Naltrexone과 ondansetron의 병합투여가 C57BL/6형 생쥐의 알코올 섭취량에 미치는 영향)

  • Kim, Hyeun-Kyeung;Kim, Sung-Gon;Kang, Cheol-Joong;Park, Sang-Ick;Kim, Won-Ho
    • Journal of Life Science
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    • v.17 no.11
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    • pp.1576-1581
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    • 2007
  • Dopamine reward pathway projecting from ventral tegmental area to nucleus accumbens is well known as playing an important role in alcohol dependence. It is supposed that this dopamine pathway is modulated by $5-HT_3$ nervous system, and it was reported that ondansetron (OND), $5-HT_3$ receptor antagonist, reduced drinking amount and increased abstinence rate in alcohol-dependent patients. The purpose of this study is to investigate the effect of combination of OND and naltrexone (NTX), non-specific opioid receptor antagonist, on alcohol intake in C57BL/6 mice. In 40 C57BL/6 mice in the state of alcohol dependence, vehicle, while OND 0.01 mg/kg, or NTX 1.0 mg/kg administrated respectively, or OND 0.01 mg/kg and NTX 1.0 mg/kg administrated simultaneously for ten days, medication effects on 2-hr alcohol, 22-hr water, 24-hr food intake and body weight were studied. When vehicle group was compared with 3 medication groups respectively, using a repeated measure ANOVA, NTX alone and vehicle groups showed a significant medication by time interaction (p=0.042) in 2-hr alcohol intake, but in the other 2 groups, OND and NTX combination group and OND alone group, there was no significant interaction with vehicle group in 2-hr alcohol intake. From these results, it is suggested that there is no effect on alcohol intake in mice treating with OND, and naltrexone#s suppression effect on alcohol intake in mice is attenuated when treating with OND and NTX simultaneously. It is supposed that a further study looking at the interactions of serotonin, dopamine and opioid nerves systems will be needed.

Reactive Oxygen Species Mediates Lysophosphatidic Acid-induced Migration of SKOV-3 Ovarian Cancer Cells (SKOV-3 난소암 세포주에서 lysophosphatidic acid 유도 세포의 이동에 있어 활성산소의 역할)

  • Kim, Eun Kyoung;Lee, Hye Sun;Ha, Hong Koo;Yun, Sung Ji;Ha, Jung Min;Kim, Young Whan;Jin, In Hye;Shin, Hwa Kyoung;Bae, Sun Sik
    • Journal of Life Science
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    • v.22 no.12
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    • pp.1621-1627
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    • 2012
  • Cell motility plays an essential role in many physiological responses, such as development, immune reaction, and angiogenesis. In the present study, we showed that lysophosphatidic acid (LPA) modulates cancer cell migration by regulation of generation of reactive oxygen species (ROS). Stimulation of SKOV-3 ovarian cancer cells with LPA strongly promoted migration. but this migration was completely blocked by pharmacological inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Inhibition of the ERK pathway had no effect on migration. Stimulation of SKOV-3 ovarian cancer cells with LPA significantly induced the generation of ROS in a time-dependent manner. LPA-induced generation of ROS was significantly blocked by pharmacological inhibition of PI3K or Akt, but inhibition of the ERK signaling pathway had little effect. LPA-induced generation of ROS was blocked by pretreatment of SKOV-3 ovarian cancer cells with an NADPH oxidase inhibitor, whereas inhibition of xanthine oxidase, cyclooxygenase, or mitochondrial respiratory chain complex I had no effect. Scavenging of ROS by N-acetylcysteine completely blocked LPA-induced migration of SKOV-3 ovarian cancer cells. Inhibition of NADPH oxidase blocked LPA-induced migration whereas inhibition of xanthine oxidase, cyclooxygenase, or mitochondrial respiratory chain complex I did not affect LPA-induced migration of SKOV-3 ovarian cancer cells. Given these results, we suggest that LPA induces ROS generation through the PI3K/Akt/NADPH oxidase signaling axis, thereby regulating cancer cell migration.

Extract of Rubus coreanus Fruits Increases Expression and Activity of Endothelial Nitric Oxide Synthase in the Human Umbilical Vein Endothelial Cells (복분자 추출물에 의한 내피세포 NO 합성효소의 활성과 발현 증가)

  • Yoon, Hyun-Joong;Park, Soo-Young;Oh, Sung-Tack;Lee, Kee-Young;Yang, Sung-Yeul
    • Journal of Life Science
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    • v.21 no.1
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    • pp.44-55
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    • 2011
  • This study aimed to investigate the effects of water extract of Rubus coreanus (RCE) on the expression and activity of endothelial nitric oxide synthase (eNOS), as well as its signal transduction pathways in human umbilical vein endothelial cells (HUVECs). The specific inhibitors of NOS show RCE treatment increases NO production in HUVECs due to the up-regulation of eNOS rather than iNOS. The real-time expression level of eNOS mRNA was also increased upon RCE treatment in HUVECs. While a PKC-specific inhibitor, RO-317549, did not alter RCE-induced NO production in HUVECs, tamoxifen (estrogen receptor-specific inhibitor), PD98059 (ERK-specific inhibitor) and LY-294002 (PI3K/Akt-specific inhibitor) did have suppressive effects. Increased NO production by RCE seems to result from a higher level of active eNOS (pSer1177). Specifically, inhibition of ERK not only decreased the level of active eNOS, but also increased the inactive form of the enzyme (pThr495) in HUVECs. This study suggests that RCE treatment increases NO production in HUVECs due to the increased expression and activity of eNOS. It is also shown that RCE-induced eNOS activation occurs partly through the binding of RCE to the estrogen receptor, along with ERK and PI3K/Akt-dependent signal transduction pathways. In addition, the regulatory binding proteins of eNOS including Hsp90 and caveolin-1 were related to these effects of RCE on eNOS activity in HUVECs.