• Title/Summary/Keyword: human life cycle

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Effects of Seasonal Cycle on Yin-Yang Five-States (계절이 오행의 상태에 미치는 영향)

  • Lee, SuBin;Kang, Jung Im;Kim, Sang-Kyun;Kim, An Na;Lee, Sang-Hee
    • The Journal of Korean Medicine
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    • v.34 no.1
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    • pp.136-145
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    • 2013
  • Objectives: Recently, Korean medicine has been explored by employing mathematical methods, which is an effort to raise Korean medicine to a higher level of scientific research. In that vein, we propose a mathematical model, analyzing the effects of seasonal cycle as an external factor in addition to the internal interactions of five-states, the engendering and the restraining. Methods: Some modified differential equations with 5-state variables were given to describe the interactions of the engendering and the restraining, and effect of seasonal cycle, and are numerically analyzed by Runge-Kutta method. We then simulated it along with time and dynamically analyzed it by Moran's I, a spatial autocorrelation. Results: We showed the effects of seasonal cycle on yin-yang five-states and applied it to the human life cycle. Conclusions: Our result is comparable to previous results in the respect that we consider the seasonal cycle and its effect on five-states, unlike others' mainly focusing on internal interaction. Furthermore, we suggest some follow-up study taking into consideration the complexity and diversity of external factors.

The Korean State and Candlelight Democracy: Paradigms and Evolution

  • Bedeski, Robert
    • Journal of Contemporary Eastern Asia
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    • v.16 no.2
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    • pp.82-92
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    • 2017
  • The Korean state evolved as a distinct entity in a region of major power convergence and conflict. All states, as human constructions, seek sovereignty and life security of their subjects/citizens, and are rotted in organic society. In the Republic of Korea, constitutional order has provided a framework for political action and a succession of regimes - authoritarianism, military dictatorship, and constitutional democracy. Since 1960 two paradigms have undergone a cycle of growth and decline, and a third, since the 2016 candlelight demonstrations in Gwanghwamun, may be the beginnning of a third generation paradigm - populist constitutionalism.

Expression of HERV-HX2 in Cancer Cells and Human Embryonic Stem Cells

  • Jung, Hyun-Min;Choi, Seoung-Jun;Kim, Se-Hee;Moon, Sung-Hwan;Yoo, Jung-Ki;Chung, Hyung-Min;Kim, Jin-Kyeoung
    • Reproductive and Developmental Biology
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    • v.32 no.2
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    • pp.105-110
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    • 2008
  • The endogenous retrovirus-like elements (HERVs) found on several human chromosomes are somehow involved in gene regulation, especially during the transcription level. HERV-H, located on chromosome Xp22, may regulate gastrin-releasing peptide receptor (GRPR) in connection with diverse diseases. By suppression subtractive hybridization screen on SV40-immortalized lung fibroblast (WI-38 VA-13), we discovered that expression of HERV-HX2, a clustered HERV-H sequence on chromosome X, was upregulated in immortalized lung cells, compared to that of normal cells. Expression of HERV-HX2 was then analyzed in various cell lines, including normal somatic cells, cancer cells, SV40-immortalized cells, and undifferentiated and differentiated human embryonic stem cells. Expression of HERV-HX2 was specifically upregulated in continuously-dividing cells, such as cancer cells and SV40-immortalized cells. Especially, HERV-HX2 in HeLa cells was highly upregulated during the S phase of the cell cycle. Similar results were obtained in hES cells, in which undifferentiated cells expressed more HERV-HX2 mRNA than differentiated hES cells, including neural precursor and endothelial progenitor cells. Taken together, our results suggest that HERV-HX2 is upregulated in cancer cells and undifferentiated hES cells, whereas downregulated as differentiation progress. Therefore, we assume that HERV-HX2 may playa role on proliferation of cancer cells as well as differentiation of hES cells in the transcriptional level.

S&T Theories and National Competitive Advantages in South Korea

  • Kim, Sang-Tae
    • World Technopolis Review
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    • v.1 no.3
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    • pp.186-191
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    • 2012
  • To understand South Korea's economic success several contending paradigms have emerged, ranging from a neo-classical explanation to a statist perspective, and Schumpeterian structuralism. The Korean miracle can be seen as a product of multiple factors involving the strategic choice of export-led growth, timely and active human-capital investment, business activism, and individual innovative ideas. However, South Korea needs more complex and innovative ideas to continue its both economic growth and S&T Development. The ideas of Schumpeterian structuralist needs to be more emphasized. Changing state-society relations and subsequent policy choice are greatly influenced by the industrial life cycle. The industrial life cycle is closely related to the historical sequencing and diffusion of technology. The complex mixture of statist-market-Schumpeterian structuralist perspectives could lead more technologically advanced society in South Korea.

Cell Cycle Arrest by Treatment of D-Ala2-Leu5-enkephalin in Human Leukemia Cancer U937 Cell. (인체혈구암세포 U937의 D-Ala2-Leu5-enkephalin처리에 의한 세포 주기 억제 효과)

  • Lee, Jun-Hyuk;Choi, Woo-Young;Choi, Yung-Hyun;Choi, Byung-Tae
    • Journal of Life Science
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    • v.19 no.5
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    • pp.620-624
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    • 2009
  • D-Ala2-Leu5-enkephalin (DADLE), a hibernation inducer, can induce hibernation-like state in vivo and in vitro. We treated U937 human leukemia cancer cells with DADLE and investigated its possible effect on transcription and proliferation. Treatment of U937 cells with DADLE resulted in growth inhibition and induction of apoptotic cell death on high-dose as measured by MTT assay and DNA flow cytometer analysis. Bcl-XL, c-IAP-2 and survivin genes especially showed decreases in mRNA levels. DADLE treatment also inhibited the levels of cyclooxygenase (COX)-2 mRNA without alteration of COX-1 expression. DNA flow cytometer analysis revealed that DADLE caused arrest of the cell cycle on low-dose, which was associated with a down-regulation of cyclin E at the transcriptional level. DADLE treatment induced a marked down-regulation of cyclin-dependent kinase (Cdk)-2, -4 and -6. In addition, treatment with DADLE decreased telomere associated genes such as, c-myc and TERT, and increased TEP-1 in U937 cells. These results suggest that DADLE can be an inhibition agent in the cell cycle of the human leukemia cancer U937 cell.

G1 Arrest of the Cell Cycle by Gomisin N, a Dibenzocyclooctadiene Lignan, Isolated from Schizandra chinensis Baill in Human Leukemia U937 Cells (오미자에서 분리된 dibenzocyclooctadiene lignan의 일종인 gomisin N에 의한 인체혈구암세포의 세포주기 G1 arrest 유발)

  • Park, Cheol;Hwang, Hye-Jin;Choi, Byung-Tae;Choi, Tae-Hyun;Kim, Byung-Woo;Choi, Young-Whan;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.20 no.7
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    • pp.977-982
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    • 2010
  • We investigated the anti-cancer effects of two dibenzocyclooctadiene lignans, gomisin A and gomisin N, isolated from Schizandra chinensis Baill, in human promyelocytic U937 cells. Gomisin N, but not gomisin A, inhibited cell growth in a concentration-dependent manner, which was associated with the induction of G1 arrest of the cell cycle. G1 arrest induced by gomisin N was correlated with down-regulation of cyclin E, cyclin-dependent kinase (Cdk) 2 and Cdk4, and a concomitant up-regulation of Cdk inhibitors such as p16 (INK4A) and p21 (WAF1/CIP1). Furthermore, gomisin N inhibited phosphorylation of retinoblastoma protein (pRB) and p130, and expression of transcription factor E2Fs. The results indicated that growth inhibition by gomisin N is related to cell cycle arrest at G1 in U937 cells and these findings suggest that gomisin N may be a useful chemotherapeutic agent.

Induction of S Phase Arrest of the Cell Cycle by Piceatannol is Associated with Inhibition of Telomerase Activity in Human Leukemic U937 Cells (Piceatannol에 의한 인체 혈구암세포의 증식 억제 및 telomerase 활성 저하)

  • Choi, Yung-Hyun
    • Journal of Life Science
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    • v.18 no.1
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    • pp.96-102
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    • 2008
  • Piceatannol is a polyphenol that is found in abundant quantities in grapes and wine. Although recent experimental data revealed the anti-cancer potency of piceatannol, the molecular mechanisms underlying the antileukemic activity have not yet been studied in detail. In the present study, we investigated further possible mechanisms by which piceatannol exerts its anti-proliferative action in cultured human leukemia U937 cells. Exposure of U937 cells to piceatannol resulted in growth inhibition and induction of apoptosis as measured by MTT assay and flow cytometry analysis, which was associated with S phase arrest of the cell cycle. Piceatannol treatment markedly inhibited the activity of telomerase, and the levels of human telomerase reverse transcriptase (hTERT) and telomerase-associated protein-1 (TEP-1), main determinants of the telomerase enzymatic activity, were progressively down-regulated by piceatannol treatment in a dose-dependent fashion. However, the levels of cyclooxygenases (COXs) expression and prostaglandin E2 (PGE2) release were not changed in piceatannol-treated U937 cells. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of piceatannol.

Extracts of Opuntia humifusa Fruits Inhibit the Growth of AGS Human Gastric Adenocarcinoma Cells

  • Hahm, Sahng-Wook;Park, Jieun;Park, Kun-Young;Son, Yong-Suk;Han, Hyungchul
    • Preventive Nutrition and Food Science
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    • v.21 no.1
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    • pp.31-37
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    • 2016
  • Opuntia humifusa (OHF) has been used as a nutraceutical source for the prevention of chronic diseases. In the present study, the inhibitory effects of ethyl acetate extracts of OHF on the proliferation of AGS human gastric cancer cells and the mode of action were investigated. To elucidate the antiproliferative mechanisms of OHF in cancer cells, the expression of genes related to apoptosis and cell cycle arrest were determined with real-time PCR and western blot. The cytotoxic effect of OHF on AGS cells was observed in a dose-dependent manner. Exposure to OHF ($100{\mu}g/mL$) significantly induced (P<0.05) the G1 phase cell cycle arrest. Additionally, the apoptotic cell population was greater (P<0.05) in OHF ($200{\mu}g/mL$) treated AGS cells when compared to the control. The expression of genes associated with cell cycle progression (Cdk4, Cdk2, and cyclin E) was significantly downregulated (P<0.05) by the OHF treatment. Moreover, the expression of Bax and caspase-3 in OHF treated cells was higher (P<0.05) than in the control. These findings suggest that OHF induces the G1 phase cell cycle arrest and activation of mitochondria-mediated apoptosis pathway in AGS human gastric cancer cells.