• 제목/요약/키워드: DNA Synthesis

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Mitomycin C에 의한 DNA 回復合成에 미치는 Thymidine 相似體의 影響 (Effects on Thymidine Analogs on Mitomycin C Induced DNA Repair Synthesis)

  • Park, Kyung-Hee;Park, Sang-Dai
    • 한국동물학회지
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    • 제20권2호
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    • pp.93-99
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    • 1977
  • HeLa $S_3$세포에서 MMC에 의해 유발된 DNA회복합성은 농도$(0.05\\sim 0.5\\mu g/ml)$에 따른 증가를 보이지 않고 그 율도 비\ulcorner적 낮아 $0.1\\sim 0.5\\mu g/ml$ 농도에서 조사한 전 세포의 $7\\sim 9%$를 나타내고 있다. 시간 변화에 따른 실험에서는 MMC를 제거한 후 24시간까지 거의 비슷한 율로 DNA회복합성이 계속되고 있다. thymidine 상사체중 BUdR을 전처리한 군에서만이 MMC에 의한 DNA회복합성을 증가시켰다. 그러나 BUdR 또는 IUdR과 MMC를 복합처리 할 경우 시간경과에 따라 정상 DNA합성은 감소된다. 이들 결과는 MMC에 의해 유발된 DNA손상은 빠르고 느린 두단계로 회복됨을 암시하는 것이라 생각된다.

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인삼에서 추출한 글리코시드가 배양한 마우스 섬유아세포의 핵산합성에 미치는 영향 (Antiproliferative Effects of Panu ginseng Glycosides on DNA Synthesis in Cultured Mouse Fibroblasts)

  • Byun, Boo-Hyeong;Shin, In-Cheol;Lee, Lil-Ha;Joe, Cheol-O
    • Journal of Ginseng Research
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    • 제19권2호
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    • pp.114-116
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    • 1995
  • Panax ginseng ginsenosides were examined for their affects on the DNA synthesis. The DNA 1 synthesis was measured by the thymidine incorporation into NIH3T3 cells. The ginsenoside, panaxytriol, $Rh_1$ and $Rh_2$ showed reduced [$^{3}H$]-thymidine incorporation. However, other ginsenosides of $Rh_1$, $Rh_2$ and $Rh_3$ did not inhibit DNA synthesis. Among the various ginsenosides, ginsenoside $Rh_2$ was found to be the most inhibitory on DNA synthesis. We suggest $Rh_2$ as one of the potential choice of antiproliferative drugs.

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DETECTION OF DNA SINGLE-STRAND BREAKS AND UNSCHEDULED DNA SYNTHESIS INDUCED BY PROCARCINOGENS IN PRIMARY CULTURES OF RAT HEPATOCYTES

  • Kim, D.H.;Kim, Bok-Ryang;K. H. Yang
    • Toxicological Research
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    • 제2권1호
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    • pp.1-7
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    • 1986
  • Procarcinogen induced DNA single-strand breaks and unschduled DNA synthesis were measured in primary rat hepatocytes culture. For DNA single-strand breaks assay, rat liver DNA was prelabeled by injection 3H-thymidine during the peak of DNA synthesis following partial hepatectomy. Hepatocytes were isolated from the rat 2 weeks after surgery by a collagenase perfusion techinique and maintained as monolayers in serum free medium on collagen-coated culture dishes. DNA sigle-strand breaks were measured by the alkaline elution techinique.

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哺乳動物細胞에 있어서 X-線에 의한 回復複製와 染色體交換 및 分裂活動과의 聯關性 (X-ray Induced Unscheduled DNA Synthesis in Relation to Chromosome Exchange and Mitotic Activity in Established Mammalian Cells)

  • Park, Sang-Dai
    • 한국동물학회지
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    • 제15권3호
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    • pp.95-100
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    • 1972
  • 回復複製(unscheduled DNA synthesis or repair replication)와 染色體交換 및 分裂活動과의 相關關係를 추구하기 위해 X-線을 處理한 4種의 哺乳動物 細胞를 材料로 回復複製 時期와 線量反應을 調査하였다. 回復複製는 調査한 4種의 細胞에서 모두 일어나고 그 率은 照射線量에 比例하며 細胞 種類에 따라 差가 난다. 그러나 回復複製가 일어나는 時期는 細胞 種類에 관계없이 X-線 照射후 2時間까지 지속되고 있다. 또 回復複製의 相對量은 細胞의 種族染色體數, 分裂活動 및 染色體交換率과 직접적인 관련이 없다. 分裂活動能力과 染色體交換은 다 線量에 比例하나 그 率은 逆比例 관계를 나타낸다.

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Pertussis Toxin Inhibits Colchicine-Induced DNA Synthesis in Human Fibroblast

  • Jang, Won-Hee;Rhee, In-Ja
    • Archives of Pharmacal Research
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    • 제17권3호
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    • pp.199-203
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    • 1994
  • Several lines evidence indicate that microtubule depolymerization initiates DNA synthesis or enhances the effects of serum or purified growth factors in many types of fibroblasts. Yet little is known about the intracellular events responsible for the mitogenic effect of microtubule disrupting agents. The effects of antitubulin agents on DNA synthesis in sparse and dense cultures in the presence or absence of serum and possible involvement of G-proteins in their mitotic action were examined. In these studies, colchicine by itself appeared to be mitogenic only for confluent quiesecent human lung fibroblasts. In sparse culture, however, colchicine inhibited serum-stimulated DNA synthesis. Colcemid, another antitubulin agent, showed similar effects of growth inhibition and stimulation in sparse and confluent cultures while lumicolhicine, inactive colchicine, did not. The mitogenic effect of two antitubulin agents, colchicine and colcemid, was partially inhibited by pertussis toxin. These data suggest that microtubular integrity is associated with the expression of either negative or positive control on DNA synthesis and mitogenic effect of antitubulin agents may be partially mediated by pertussis toxin-sensitive G protein.

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돼지 태아 신장세포에 있어 parvovirus KBSH의 DNA 복제과정에 관하여 (The Replication of Parvovirus KBSH DNA in the Embryonic Swine Kidney Cells)

  • 이성욱;김연수;강현삼
    • 미생물학회지
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    • 제25권1호
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    • pp.34-39
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    • 1987
  • 활발히 생장하고 있는 돼지 태아 선상세포에서. 정상적인 human 세포 배양으로부터 분리된 single-stranded DNA parvovirus KBSH 의 초기 증식 특성을 알아보기 위해, 합성되는 virus의 hemagglutinating(HA) antigen 양과 virus의 d double-stranded replicative form(RF) DNA 합성 속도를 조사하였다virus의 RFDNA 합성이 시작되는 감염 후 15-16 시간 때와 거의 동시에 virus에 감엽된 숙주셔1포의 DNA 합성 속도가 감소하기 시작하였으며, virus의 RF DNA 합성속도 가 최대에 년한 후 간소하시 시작하는 감염 후 24시간 때부터 virus의 HA antigen이 배지상으로 방출되기 시작하였다. 그러고 virus의 RF DNA 복체에는 virus에 감염된 세포에서 감염 후 10-14시간 때에 형성되는 만액섣들이 관여함을 말았다.

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Modulation of Chemical Carcinogen-Induced Unscheduled DNA Synthesis by Dehydroepiandrosterone (DHEA) in the Primary Rat Hepatocytes

  • Kim, Seung-Hee;Han, Hyung-Mee;Kang, Seog-Youn;Jung, Ki-Kyung;Kim, Tae-Gyun;Oh, Hye-Young;Lee, Young-Kyung;Rheu, Hang-Mook
    • Archives of Pharmacal Research
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    • 제22권5호
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    • pp.474-478
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    • 1999
  • Modulation of unscheduled DNA synthesis by dehydroepiandrosterone (DHEA) after exposure to various chemical carcinogens was investigated in the primary rat hepatocytes. Unscheduled DNA synthesis was induced by treatment of such direct acting carcinogens as methly methanesulfonate (MMS) and ethyl methanesulfonate (EMS) or procarcinogens including benzo(a)pyrene (BaP) and 7, 12-dimethylbenz(a)anthracene (DMBA). Unscheduled DNA synthesis was determined by measuring [methyl-3H]thymidine radioactivity incorporated into nuclear DNA of hepatocytes treated with carcinogens in the presence or absence of DHEA. Hydroxyurea $(5{\times}10^{-3} M)$was added to growth medium to selectively suppress normal replication. DHEA at concentrations ranging from $(1{\times}10^{-6} M)$ to$(5{\times}10^{-4} M)$ did not significantly inhibit unscheduled DNA synthesis induced by either MMS $(1{\times}10^{-4} M)$ or EMS $(1{\times}10^{-2} M)$. In contrast, DHEA-significantly inhibited unscheduled DNA synthesis induced by BaP $(6.5{\times}10^{-5} M)$ and DMBA.$(2{\times}10^{-5} M)$. DHEA-induced hepatotoxicity in rats was examined using lactate dehydrogenase (LDH) release as an indicator of cytotoxicity. DHEA exhibit no significant increase in LDH release compared with the control at 18 h. These data suggest that nontoxic concentration of DHEA does not affect the DNA excision repair process, but it probably influence the enzymatic system responsible for the metabolic activation of procarcinogens and thereby decreases the amount of the effective DNA adducts formed by the ultimate reactive carcinogenic species.

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MODULATION OF INSULIN-STIMULATED DNA SYNTHESIS BY CHOLERA TOXIN IN BOVINE MAMMARY FIBROBLASTS

  • Yuh, I.S.;Park, C.K.;Han, J.Y.;Sheffield, L.G.
    • Asian-Australasian Journal of Animal Sciences
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    • 제6권4호
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    • pp.483-489
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    • 1993
  • Bovine fibroblasts were cultured in Dulbecco's Modified Eagle's Medium and then treated with control, insulin (I, $1{\mu}g/ml$), cholera toxin (CT, 0.1-100 ng/ml) or CT (0.1-100 ng/ml) + I ($1{\mu}g/ml$). Cholera toxin, an activator of adenylate cyclase, significantly decreased insulin induced DNA synthesis (p<0.05). The modulation of DNA synthesis apparently involves events occurring in early stage of cell growth, at least between the first 4 and 8 hour of CT treatment. Insulin induced collagen as well as noncollagen synthesis in cell layer, however, these syntheses were reduced by addition of cholera toxin (p<0.05) but were not completely reduced. It is not clear whether the reduction of insulin-induced cell layer collagen or noncollagen proteins by CT is involved in the inhibitory effect on insulin-induced DNA synthesis. However, we could rule out the hypothesis that insulin-induced DNA synthesis is reduced by CT-induced cellular differentiation.

DNA 분자를 형틀로 이용한 Polypyrrole 나노와이어의 합성시 pH 효과 (Effect of pH on Synthesis of Polypyrrole Nanowires by Using DNA Molecule Templates)

  • 최용훈;김경섭;김남훈;노용한
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 추계학술대회 논문집
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    • pp.109-110
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    • 2007
  • Pyrrole and DNA can be used for synthesis of conducting nanowires. Protonated pyrrole and negatively charged DNA are absorbed by electrostatic interaction. The level of absorbance is related to pH of pyrrole. Therefore, DNA immobilized and aligned on the 3-aminopropyltrimethoxysi1ane (APTES) modified Si surface. Positive pyrrole monomers was deposited on aligned DNA for the synthesis of nanowire in various pH condition. And polypyrrole nanowires were synthesized by polimerization with ammonium persulfate (APS). These polypyrrole nanowires were measured by AFM, and then we found optimal pH level for the synthesis of nanowires.

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