• Title/Summary/Keyword: $K_e$-factor

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Down-regulation of Tcf-1 Expression by Activation-induced Apoptosis of T Cell Hybridoma

  • Jeong, Sun-Joo;Jeon, Sung-Ho;Yim, Jeong-Bin;Park, Sang-Dai;Rho, Hyun-Seung
    • Animal cells and systems
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    • v.2 no.3
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    • pp.403-410
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    • 1998
  • The Tcf-1 (T cell specific factor-1) is a transcription factor uniquely expressed in T-lineage cells. Its expression is developmentally regulated, which is high in the specific stage of immature thymocytes, but is much lower in mature T cells. We cloned the Tcf-1 gene by subtractive hybridization and found it to be highly expressed in the thymus compared to the mRNA level in the spleen as expected. Since apoptosis occurs enormously in the thymus, we were interested in whether Tcf-1 gene expression could be regulated by such a high level of apoptotic assault. By using T cell hybridoma 70.7 cells, we induced apoptosis by incubating cells with anti-CD3 antibody in vitro. After apoptosis induction, Tcf-1 mRNA level was found to be significantly reduced compared to normal cells. Since Tcf-1 is a transcription factor for the CD3-e gene, we tested how CD3-e expression is regulated in apoptotic cells. The surface level of CD3-e protein is also down-regulated after apoptosis induction. Such a down-modulation of CD3-e protein would reduce the TCR/CD3 complex on the cell surface, which would be an important regulator for T cell apoptosis.

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Correlation between Vocal Indicators and Buzhongyiqi-Tang Questionnaire (음성 진단 지표와 보중익기탕 적응증과의 상관성 연구)

  • Cho, Shin-Woong;Park, Young-Bae;Park, Young-Jae
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.13 no.1
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    • pp.81-88
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    • 2009
  • Purpose : To find out correlation between the Vocal indicators and the 'Buzhongyiqi-Tang questionnaire'. Method : The 'Buzhongyiqi-Tang questionnaire' is given to 83 healthy adults and collected their voice /a/ /e/ /i/ /o/ /u/. Analyze mean values of each factors of the Vocal indicators and the 'Buzhongyiqi-Tang questionnaire'. Conclusions : R square values of /i/ sound in factor 1 and factor 3 of 'Buzhongyiqi-Tang questionnaire' are noticeably high. The value of vocal diagnosis index F0, Fundamental Frequency, in Factor 1 and factor 3 of 'Buzhongyiqi-Tang questionnaire' are considerable. The research has shown conclusively that there is a link between The value of vocal diagnosis index F0 and Factor 3, lung deficiency factor, of 'Buzhongyiqi-Tang questionnaire'.

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Studies on the Influence Factors of E-commerce Adoption: The Perspective of Suppliers' E-commerce (전자상거래 도입 영향요인들에 관한 통합적 연구: 공급업체 전자상거래를 중심으로)

  • Choe, Jong-Min
    • Information Systems Review
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    • v.15 no.1
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    • pp.1-24
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    • 2013
  • This study empirically investigated inter-relationships among the influence factors on the adoption of e-commerce, which are classified as cause factor (i.e., perceived environmental uncertainty and competition), facilitators (i.e., perceived economic benefits, inter-organizational trust, suppliers' pressure and capability and asset specificity) and support factor (i.e., top management's support and organizational resource capability). The results of regression analyses showed that competition, inter-organizational trust, suppliers' pressure and capability, top management's support, and organizational resource capability have a positive impact on the adoption of e-commerce. In the analyses of inter-relationships among the influence factors, it was found that perceived environmental uncertainty positively influences suppliers' pressure and capability and perceived economic benefits, and competition has a positive impact on asset specificity. It was also observed that perceived economic benefits, inter-organizational trust and suppliers' pressure and capability positively affect top management's support, and inter-organizational trust and suppliers' pressure and capability have a positive impact on organizational resource capability. With mediating regression analyses, it was found that competition has an indirect impact on the adoption of e-commerce through the effect on perceived economic benefits, suppliers' pressure and capability, organizational resource capability and top management's support. The results of mediating regression analyses also showed that suppliers' pressure and capability and perceived economic benefits have indirect effects on the adoption of e-commerce through the effects on top management's support and organizational resource capability. From these results, it is concluded that intense competition causes the activation of facilitators, and the facilitators contribute to both the enhancement of top management support and the creation of organizational resource capability, which are directly linked to the adoption of e-commerce.

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E1/E2 of Hepatitis C Virus Genotype-4 and Apoptosis

  • Zekri, Abdel-Rahman N;Sobhy, Esraa;Hussein, Nehal;Ahmed, Ola S;Hussein, Amira;Shoman, Sahar;Soliman, Amira H;El-Din, Hanaa M Alam
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.7
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    • pp.3131-3138
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    • 2016
  • Several studies have addressed the possible role of hepatitis C virus genotype-4 (HCV GT4) in apoptosis. However, this still not fully understood. In the current study a re-constructed clone of E1/E2 polyprotein region of the HCV GT4 was transfected into the Huh7 cell line and a human apoptotic PCR array of 84 genes was used to investigate its possible significance for apoptosis. Out of the 84 genes, only 35 showed significant differential expression, 12 genes being up-regulated and 23 down-regulated. The highest-up regulated genes were APAF1 (apoptotic peptidase-activating factor 1), BID (BH3 interacting domain death agonist) and BCL 10 (B-cell CLL/lymphoma protein 10) with fold regulation of 33.2, 30.1 and 18.9, respectively. The most down-regulated were FAS (TNF receptor super family), TNFRSF10B (tumor necrosis factor receptor super-family member 10b) and FADD (FAS-associated death domain) with fold regulation of -30.2, -27.7 and -14.9, respectively. These results suggest that the E1/E2 proteins may be involved in HCV-induced pathogenesis by modulating apoptosis through the induction of the intrinsic apoptosis pathway and disruption of the BCL2 gene family.

Developmental Expression of Eukaryotic Initiation Factor 4E (eIF4E) and eIF4E-binding Protein 1 (eIF4EBP1) in Rat Hippocampal Neurons (발생단계별 해마신경세포에서 eIF4E 및 eIF4EBP1의 표현)

  • Park, Jaewan;Moon, Il Soo
    • Journal of Life Science
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    • v.23 no.7
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    • pp.941-946
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    • 2013
  • Local protein synthesis at subsynaptic sites plays a key role in the regulation of the protein composition in local domains. In this study, we carried out immunocytochemistry of cultured rat hippocampal neurons in various developmental stages to investigate the expression of eIF4E and its binding protein, eIF4EBP1. Both proteins were distributed in dendrites. In addition, eIF4EBP1 was highly expressed in the nucleus throughout the development, whereas eIF4E was not expressed in the nucleus. Punctate expression of eIF4E and eIF4EBP1 was evident in DIV 3. The colocalization rates of eIF4E or eIF4EBP1 puncta with PSD95 were higher in the dendrogenic than in the mature stages. In contrast, the colocalization rates of eIF4E and eIF4EBP1 puncta were higher in the mature than in the dendrogenic stages. As eIF4E is inactive when it is bound to eIF4EBP1, these data indicate that most dendritic eIF4E's are active during development but that they are mostly under inhibition in mature neurons.

Effective Detective Quantum Efficiency (eDQE) Evaluation for the Influence of Focal Spot Size and Magnification on the Digital Radiography System (X-선관 초점 크기와 확대도에 따른 디지털 일반촬영 시스템의 유효검출양자효율 평가)

  • Kim, Ye-Seul;Park, Hye-Suk;Park, Su-Jin;Kim, Hee-Joung
    • Progress in Medical Physics
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    • v.23 no.1
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    • pp.26-32
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    • 2012
  • The magnification technique has recently become popular in bone radiography, mammography and other diagnostic examination. However, because of the finite size of X-ray focal spot, the magnification influences various imaging properties with resolution, noise and contrast. The purpose of study is to investigate the influence of magnification and focal spot size on digital imaging system using eDQE (effective detective quantum efficiency). Effective DQE is a metric reflecting overall system response including focal spot blur, magnification, scatter and grid response. The adult chest phantom employed in the Food and Drug Administration (FDA) was used to derive eDQE from eMTF (effective modulation transfer function), eNPS (effective noise power spectrum), scatter fraction and transmission fraction. According to results, spatial frequencies that eMTF is 10% with the magnification factor of 1.2, 1.4, 1.6, 1.8 and 2.0 are 2.76, 2.21, 1.78, 1.49 and 1.26 lp/mm respectively using small focal spot. The spatial frequencies that eMTF is 10% with the magnification factor of 1.2, 1.4, 1.6, 1.8 and 2.0 are 2.21, 1.66, 1.25, 0.93 and 0.73 lp/mm respectively using large focal spot. The eMTFs and eDQEs decreases with increasing magnification factor. Although there are no significant differences with focal spot size on eDQE (0), the eDQEs drops more sharply with large focal spot than small focal spot. The magnification imaging can enlarge the small size lesion and improve the contrast due to decrease of effective noise and scatter with air-gap effect. The enlargement of the image size can be helpful for visual detection of small image. However, focal spot blurring caused by finite size of focal spot shows more significant impact on spatial resolution than the improvement of other metrics resulted by magnification effect. Based on these results, appropriate magnification factor and focal spot size should be established to perform magnification imaging with digital radiography system.

Phosphorylation of Elongation Factor-2 And Activity Of Ca2+/Calmodulin-Dependent Protein Kinase III During The Cell Cycle

  • Suh, Kyong-Hoon
    • BMB Reports
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    • v.33 no.2
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    • pp.103-111
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    • 2000
  • Phosphorylation of the eukaryotic elongation factor 2 (eEF-2) blocks the elongation step of translation and stops overall protein synthesis. Although the overall rate of protein synthesis in mitosis reduces to 20% of that in S phase, it is unclear how the protein translation procedure is regulated during the cell cycle, especially in the stage of peptide elongation. To delineate the regulation of the elongation step through eEF-2 function, the changes in phosphorylation of eEF-2, and in activity of corresponding $Ca^{2+}$/calmodulin (CaM)-dependent protein kinase III (CaMK-III) during the cell cycle of NIH 3T3 cells, were determined. The in vivo level of phosphorylated eEF-2 showed an 80% and 40% increase in the cells arrested at G1 and M, respectively. The activity of CaMK-III also changed in a similar pattern, more than a 2-fold increase when arrested at G1 and M. The activity change of the kinase during one turn of the cell cycle also demonstrated the activation at G1 and M phases. The activity change of cAMP-dependent protein kinase (PKA) was reciprocal to that of CaMK-III. These results indicated: (1) the activity of CaMK-III was cell cycle-dependent and (2) the level of eEF-2 phosphorylation followed the kinase activity change. Therefore, the elongation step of protein synthesis might be cell cycle dependently regulated.

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Insulin-like Growth Factor-1 (IGF-1) Gene Expression Is Enhanced under Hypothermia but Depressed under Additional Ischemic Stimulus

  • Kwon, O-Yu;Kwon, Kisang;Yu, Kweon;Kim, Seung-Whan
    • Biomedical Science Letters
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    • v.21 no.2
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    • pp.126-130
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    • 2015
  • There are several studies that show hypothermia improves cellular ischemia damages on experimental and clinical bases. However, its exact molecular mechanisms are unclear. In this study, we demonstrate that hypothermia induced insulin-like growth factor 1 (IGF1) gene expression, and its expression was dramatically decreased under ischemic insults. It was also demonstrated that hypothermia activated endoplasmic reticulum (ER) stress sensors especially both the phosphorylation of $eIF2{\alpha}$ (eukaryotic translation initiation factor 2 alpha) and ATF6 (activating transcription factor-6) proteolytic cleavage. However, the factors of apoptosis and autophagy were not associated with hypothermia. We suggest that hypothermia-treated IGF1 gene expression after ischemia may show a good possibility for the development of treatments and diagnostic methods in cerebral ischemic damages.

HIF-1α-Dependent Induction of Carboxypeptidase A4 and Carboxypeptidase E in Hypoxic Human Adipose-Derived Stem Cells

  • Moon, Yunwon;Moon, Ramhee;Roh, Hyunsoo;Chang, Soojeong;Lee, Seongyeol;Park, Hyunsung
    • Molecules and Cells
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    • v.43 no.11
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    • pp.945-952
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    • 2020
  • Hypoxia induces the expression of several genes through the activation of a master transcription factor, hypoxia-inducible factor (HIF)-1α. This study shows that hypoxia strongly induced the expression of two carboxypeptidases (CP), CPA4 and CPE, in an HIF-1α-dependent manner. The hypoxic induction of CPA4 and CPE gene was accompanied by the recruitment of HIF-1α and upregulation in the active histone modification, H3K4me3, at their promoter regions. The hypoxic responsiveness of CPA4 and CPE genes was observed in human adipocytes, human adipose-derived stem cells, and human primary fibroblasts but not mouse primary adipocyte progenitor cells. CPA4 and CPE have been identified as secreted exopeptidases that degrade and process other secreted proteins and matrix proteins. This finding suggests that hypoxia changes the microenvironment of the obese hypoxic adipose tissue by inducing the expression of not only adipokines but also peptidases such as CPA4 and CPE.