• Title/Summary/Keyword: Effect of Regulation

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LPS-induced Imbalanced Expression of Hepatic Vascular Stress in Hepatic Ischemia and Reperfusion

  • Kim, Sung-Ho;Park, Sun-Mee;Lee, Sun-Mee
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.125.2-125.2
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    • 2003
  • Hepatic ischemia and reperfusion predisposes the liver to secondary stresses such as endotoxemia possibly via dysregulation of the hepatic microcirculation secondary to imbalanced regulation of vascular stress gene. In this study, we determined the effect of endotoxin on hepatic vasoregulatory gene expression in response to hepatic ischemia and reperfusion (I/R). Rats were subjected to 90 min of hepatic ischemia and 6 h of reperfusion. Lipopolysaccharide (LPS, 1 mg/kg) was injected intraperitoneally after reperfusion. (omitted)

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Chemopreventive effect of Ginkgo biloba extract on breast cancer: Regulation of estrogen level

  • Oh, Seung-Min;Kim, Yun-Hee;Chung, Kyu-Hyuck
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.282.2-283
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    • 2002
  • In situ and circulating estrogen is the most important endocrine hormone that promotes the growth of hormone-dependent breast cancer. Consequently. decrease of estrogen on in situ and circulation can inhibit breast cancer. Estrogen is mainly produced by the ovary in premenopausal women and by peripheral tissues such as adipose tissues in postmenopausal women. The cytochrome p450 (CYP19), aromatase. is a key enzyme in the synthesis of estrogen hormones. (omitted)

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Design and Analysis of High Stability Stabilized Power Source (고안정도 안정화전원의 설계와 해석)

  • Kim, Joo-Hong;Bo, Sim-Kwang
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.14 no.5
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    • pp.22-28
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    • 1977
  • This is a design and analysis of the D.C. highly stabilized power source. This appratus has 10**-7 order of the voltage regulation and 40V, 1.5A, continuosly variable D.C. output. Authors inspected the effect of the OP Amp, FET and the load circuit to the stationary and transient characteristics of the apparatus. Authors found that it is a useful method for high performance of the stabilized power source to utilize IC OP Amp and FET as the elements of it.

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Anethole-Induced Regulation of T-Cell Function Through the Blocking of Mitogen-Activated Protein Kinases Signaling

  • Yea, Sung-Su
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2003.10b
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    • pp.175-175
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    • 2003
  • In the present study, we show the inhibitory effect of anethole, a substituted alkenylbenzene found in a variety of foods and essential oils, on T lymphocyte functions. Anethole produced an inhibition of concanavalin A-induced lymphoproliferation in B6C3F1 mouse splenocytes.(omitted)

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Synthesis of 2-(3'-azido-and 3'-amino-3'-deoxy-$\beta$-D-ribofuranosyl)-thiazole-4- carboxamide

  • Shin, Ji-Hye;Liang, Cheng-Wu;Chun, Moon-Woo
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.184.3-185
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    • 2003
  • Inosine 5'-monophosphate dehydrogenase (IMPDH) is a critical enzyme in the regulation of cell proliferation and differentiation. This enzyme catalyzes the $NAD^+$-dependent oxidation of IMP to XMP, the rate limiting step in de novo biosynthesis of guanine nucleotides. Therefore, the biochemical effect of IMPDH inhibition in sensitive cell types is decrease in intracellular guanine nucleotide levels, and the decrease in cellular GTP and deoxy GTP pool levels blocks DNA and RNA synthesis in rapidly proliferating tumor cells. (omitted)

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Involvement of G1 arrest and caspase-3 activation in apoptosis induced by bovine lactoferricin

  • Yoo, Yung-Choon;Lee, Kyung-Bok
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.325.2-325.2
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    • 2002
  • We investigated the effect of bovine lactoferricin (Lfcin-B) on cell cycle regulation and caspase activation in tumor cells. Treatment with Lfcin-B resulted in the production of intracellular reactive oxygen species (ROS) during apoptosis of THP-1 cells. Biochemical analysis revealed that Lfcin-B-induced apoptosis. the cell cycle arrest and caspase activation were completely abrogated by addition of an antioxidant such as N-acetylcysteine(NAC). (omitted)

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Transcriptional Regulation of the Drosophila Proliferating Cell Nuclear Antigen Gene and raf Proto-oncogene by Ursolic Acid in Drosophila Cultured Kc Cells

  • Park, Thae-Yeong;Rhee, Sang-Hoon;Kim, Han-Do;Kim, Chong-Rak;Kang, Ho-Sung;Yoo, Mi-Ae
    • Animal cells and systems
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    • v.1 no.1
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    • pp.151-155
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    • 1997
  • Promoter of the Drosophila proliferating cell nuclear antigen (PCNA) gene contains DRE (Drosophila DNA replication-related element) required for the high level expression of replication-related genes. Recently, we found that promoter region of the D-raf (a Drosophila homolog of the human c-raf-1) contains two sequences homologous to the DRE and demonstrated the DRE/DREF (DRE-binding factor) involvement in regulation of the D-raf gene. In this study, using ursolic acid (UA), a pentacyclic triterpene acid reported to possess antitumor activities, we examined effects of UA on proliferation of the Drosophila cultured Kc cells and on expression of the PCNA and D-raf genes. UA showed an inhibitory effect on proliferation of the Kc cells in a concentration-dependent manner in DNA content assays and [3H]thymidine incorporation assays. The IC50 value of anti-proliferative effects of UA in DNA content assays was about 7.5uM. UA showed inhibitory effects on expression of the PCNA as well as on that of the D-raf, which were examined with the reporter plasmic p5'-168DPCNACAT or p5'-878DrafCAT, respectively. The results obtained in the present study suggest that expression of the PCNA and D-raf genes is coordinately regulated in at least UA-treated Kc cells and that down-regulation of expression of the PCNA and D-raf genes might be related with the antitumor activities of UA.

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Calcium Ion Effect on the Sugar-H+ -Cotransport System in Chlorella vulgaris (Chlorella vulgaris의 당류 능동수송계에 미치는 칼슘 이온의 영향)

  • 조봉희
    • Journal of Plant Biology
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    • v.36 no.4
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    • pp.321-326
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    • 1993
  • Sugar uptake is accompanied with H+-substrate-symport generally. Both H+/sugar-and H+/K+ stoichiometries during the sugar-uptake have been reported to be exactly 1 : 1. This paper reports that the stoichiometries were enhanced dramatically by the addition of CaCl2 into the medium and by the high cell density of 200 $\mu$L pc/mL. The concentration of free Ca2+ ions in the cells increased significantly with cell density. It is suggested that the free Ca2+ ions are responsible for the change of stoichiometry of sugar transport system by regulation of H+ ion level of biomembrane.

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Mistletoe Lectin Induces Apoptosis and Telomerase Inhibition in Human A253 Cancer Cells through Dephosphorylation of Akt

  • Choi, Sang-Hoi;Lyu, Su-Yun;Park, Won-Bong
    • Archives of Pharmacal Research
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    • v.27 no.1
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    • pp.68-76
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    • 2004
  • Mistletoe lectin has been reported to induce apoptosis in different cancer cell lines in vitro and to show antitumor activity against a variety of tumors in animal models. We previously demonstrated the Korean mistletoe lectin (Viscum album var. coloratum, VCA)-induced apoptosis by down-regulation of Bcl-2 and telomerase activity and by up-regulation of Bax through p53- and p21-independent pathway in hepatoma cells. In the present study, we observed the induction of apoptotic cell death through activation of caspase-3 and the inhibition of telomerase activity through transcriptional down-regulation of hTERT in the VCA-treated A253 cells. We also observed the inhibition of telomerase activity and induction of apoptosis resulted from dephosphorylation of Akt in the survival signaling pathways. In addition, combining VCA with the inhibitors of phosphatidylinositol 3-kinase (PI3-kinase) upstream of Akt, wortmannin and LY294002 showed an additive inhibitory effect of telomerase activity. In contrast, the inhibitor of protein phosphatase 2A (PP2A), okadaic acid inhibited VCA-induced dephosphorylation of Akt and inhibition of telomerase activity. Taken together, VCA induces apoptotic cell death through Akt signaling pathway in correlated with the inhibition of telomerase activity and the activation of caspase-3. From these results, together with our previous studies, we suggest that VCA triggers molecular changes that resulting in the inhibition of cell growth and the induction of apoptotic cell death of cancer cells, which suggest that VCA may be useful as chemotherapeutic agent for cancer cells.

The Effects of Coloring Admixture on the Material Properties of Color Concrete (착색재가 칼라콘크리트의 물성에 미치는 영향)

  • 이성로;김종식
    • Proceedings of the Korea Concrete Institute Conference
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    • 2000.10a
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    • pp.150-154
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    • 2000
  • Coloring admixture is used for take color inside and outside of mortar and concrete, differently form pigment and spray paint take color limited surface. In our country, Using the coloring admixture is very slight and regulation is not yet about it. But that is expected the increase with raising the standard of living. Especially it is used to civil structure like dam and seawall for the environment harmony. Then we observe, in this experiment, the effect of coloring admixture on the material properties of color concrete and propose the suitable mix-proportion of color concrete.

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