• The Korean Journal of Zoology
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• v.37 no.4
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• pp.437-477
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• 1994

The DNA replication of human Iyrnphocvtes was studied using Bromodeo3fyuridine incorporation. The characteristic patterns of dvnamlc banding were analysed. Human chromosomal ONA was synthesized in a segmental but highly coordinated fashion. Each chromosome replicates according to its innate pattern of chromosome structure (bandinsl. R-positive bands are demonstrated as the initiation sites of DNA synthesis, and G-bnads initiate replication after it has been completed in the autosomal R-bands. Many researchers demonstrated that developmental or induced methvlation of DNA can inactivate the associated gene loci. Such DNA methylation can be reversed and specific genes reactivated by treatment with 5-azacvtidine. We treated the hvpomethvlating agent 5-azacvtidine and tested for changes of DNA replication pattern. Treatment with 5-azacytidine causes an advance in the time of replication. These observed changes in timing of replication suggest that DNA methvlation may modify regional groups of genes in concert.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.4
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• pp.221-226
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• 2003

With the current rapid development of nanotechnology and synthesis technology for designed oligonucleotides or oligonucleotide-modified nanoparticle conjugates, the combined strategies have become one of the most valuable methods in detection technology for DNA analysis. Using the uniquely recognizable interactions of pre-designed DNA molecules in assembling nanoparticles, various novel approaches have been recently developed towards detecting specific DNA sequences. Here we describe the key fundamentals and issues of this promising strategies ranging from the initial findings of rationally designed DNA-based assembly of nanoparticles to the extended chip-based detection system. Some limitations of these new strategies and possible approaches will be also discussed for the practical application in the area of DNA microarray detection.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.535-540
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• 1990

Bacitlus sphaericus ts-Dl290 was characterized comparatively with the wild type strain 1593 by themeasurements of the biosynthesis of total DNA, RNA and protein on the temperature-shift culturesat permissive temperature of $30^{\circ}C$ and at nonpermissive temperature of $42^{\circ}C$. The growth patterns of the wild type strain and ts-Dl290 were similar at $30^{\circ}C$, but at 4Z C the mutant almost did not grow (temperature-sensitivity). When the growth temperatures of both stains were shifted-up from $30^{\circ}C$ to $42^{\circ}C$ after a 4 hour culture, their growths were normal, but when shifted-down from $42^{\circ}C$ to $30^{\circ}C$ after a 4 h culture, the mutant did not grow. When shifted up from $30^{\circ}C$ to $42^{\circ}C$ after a 4 hculture, the DNA syntheses of the two strains were at a normal rate for 1 h, but after 1 h the biosynthesesdecreased. The rate of DNA synthesis of the wild type strain at the nonpermissive temperature was about 93%, and that of the mutant was about 50% of the ratio of the wild type strain, and the RNA synthesis of the wild type strain was maintained for 3 h, and that of the mutant for 2 h. Thereafter the RNA synthesis decreased, and the synthesis of proteins in the both strains were similarlykept high for 8 h. The reversibility of the DNA synthesis of the mutant at $42^{\circ}C$ was lessened whenthe culture times were increased.re times were increased.

• The Korean Journal of Zoology
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• v.15 no.1
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• pp.1-14
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• 1972

The effect of 400 R of whole-body X-irradiation on DNA synthesis, DNA degradation, CdR-aminohydrolase activity and oxygen uptake in the liver, spleen and thymus of the rat has been studied in connection with the radiosensitivity of these tissues. The rate of CdR-2-$^14 C$ incorporation has been followed during the postirradiation period and has been correlated with the increased levels of CdR-aminohydrolase activity druing this period. The postirradiation period comprises radiation reaction and tissue regeneration periods. During the period of radiation reaction, markedly decreased precursor incorporation, decreased tissue levels of DNA and decreased uptake of oxygen are noted as well as an increase in the CdR-aminohydrolase activity. The period of regeneration appears to consist in two discrete phases. The first phase reveals a return of CdR-aminohydrolase activity and the second phase is highlighted by a markedly increased rate of labeled CdR incorporation. Various events occurring during the radiation reaction period and the regeneration period in the three tissues studied can be considered qualitatively the same, differing only in the degree of acute cell death, in the duration of the delay of DNA synthesis in the sruviving cells, and in the rate of recovery resulting from accelerated cell replication during the period of regeneration. A possible biochemical mechanism involved in the DNA synthesis and degradation, in connection with the inreased levels of CdR-aminohydrolase after irradiation, has been briefly discussed.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.148-158
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• 1991

The purpose of this research was to establish the culture condition for dissociated submandibu -lar gland (SG) cells. After trypsin digestion of SG from 3-4 weeks old mice, dissociated cells were cultured in 1OO/o fetal bovine serum-Dulbecco's modified Eagle's medium (FBS-DME) or 0.5-2% low protein serum replacement-DME (LPSR-DME) on plastic surface to form monolayer. The effects of FBS, LPSR and hormones on the growth and function of cultured SG cells were examined. SG cells dissociated by enzyme were successfully cultured and were characterized as epithelial-like cells by light and electron microscope. The maximal DNA synthesis of cultured SG cells was achieved by DME containing 5-10% FBS. The same results were obtained when the effects of LPSR on cell proliferation were examined up to a LPSR concentration of 2%. SG cells cultured in 20/o LPSR-DME expressed a population doubling time of 42.5 hrs and a saturation density of 1.2 $\times$10 5cell/cm$^2$. Dihydrotestosterone (DHT) in medium did not influence on the DNA synthesis of the cultured SG cells, but stimulated protein synthesis of the SG cells. Thyroxine (T4) stimulated protein synthesis of the SCI cells markedly in a dose-dependent fashion. EGF secretion by the cultured SG cells increased significandy by DHT and or T4 trearment. This finding indicated that secretion of EGF by the SG cells was under the control of the hormones such as androgen and thyroid hormones. It seems to be that the culture condition described here can be used as a useful tool for further research on the SCI cells.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.857-862
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• 2005

This study investigated the proliferation and DNA synthesis inhibitory effect of concentrations ($0.01\%$, $0.1\%$, $0.25\%$, $0.5\%$) when added whole molecular-, 40 kDa-, or 10 kDa polymannuronate on human colon cancer cells, HT-29, DLD-1, and WiDr, in vitro. In order to determine the proliferation inhibitory effect of low-molecularized polymannuronate, the treatment of whole molecular-, 40 kDa-, 10 kDa-, polymannuronate ($0.25\%$) to the HT-29 cancer cells inhibited proliferation of cancer cells by $41\%$, $69.1\%$, and $75.6\%$, respectively. DLD-1 cancer cell was not relation of molecular weight and concentration. WiDr cancer cell depend on concentration without molecular weight. In addition, whole molecular-, 40 kDa-, 10 kDa poly mannuronate ($0.25\%$) significantly inhibited DNA synthesis of HT-29 cancer .cells by $78\%$, $58\%$, and $56\%$, respectively. And morphological changes not found under microscope by polymannuronate. Therefore polymannuronate would be helpful to colon cancer treatment as well as cancer prevention and this study would be the basic source for further research of polymannuronate.

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.685-691
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• 2005

Growth and DNA synthesis inhibitory effects of doenjang methanol extract and its solvent fractions on AGS human gastric adenocarcinoma cells, Hep 3B human hepatocellular carcinoma cells, HT-29 human colon cancer cells and MG-63 human osteosarcoma cells were studied. The treatment of doenjang methanol extract ($ 200{\mu}g/ml $) with the AGS, Hep 3B, HT-29 and MG-63 cancer cells after 6 days of incubation inhibited the growth of cancer cells by $32\%$, $51\%$, $84\%$ and $33\%$, respectively. To separate active compounds of doenjang, doenjang methanol extract was fractionated with dichloromethane, ethylacetate, and buthanol. Among the solvent fractions, the dichloromethane and ethylacetate fractions showed the highest growth inhibitory effects on various cancer cells. For example, the dichloromethane and ethylacetate fractions ($200a{\mu}g/ml$) sig-nificantly inhibited the growth of various cancer cells by $89\∼96\%$ and$62\∼86\%$, respectively. DNA synthesis of AGS and Hep 3B cancer cells was significantly inhibited by adding dichloromethane fraction ($200{\mu}g/ml$) up to $94\%$ and $80\%$, respectively. Similarly, the ethylacetate fraction ($ 200\mug/ml $) showed a $ 95\% $ inhibition rate of DNA synthesis in AGS cells. These results suggest that the dichloromethane and ethylacetate fractions have specific active compounds, which will explain this anticancer effect of doenjang.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.36-38
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• 1988

We have studied the ginsenoside effect on DNA RNA and protein synthesis in bone marrow. Ginseng was found to have a beneficial effect on ${\alpha}-napthyl-isothio-cyanate-induced$ hepatobiliary damage. Stimulatory effects of some ginsenosides were shown for cell proliferation and DNA synthesis in a culture liver cell line. The clinical applicability of ginseng on liver diseases will be discussed in relation to traditional medicine.

• The Korean Journal of Zoology
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• v.34 no.3
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• pp.410-419
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• 1991

마우스 악하선 배양세포의 DNA와 단백질 합성 및 epidermal growth factor(EGF) 분비에 미치는 isoproterenol(IPR)의 효과를 조사하였다. 마우스 악하선으로부터 분리되어 배양된 상피형세포의 DNA및 단백질 합성은 IRP에 의해 농도 의존적으로 현저하게 감소하였다. 이와는 달리 IPR처리 1시간 후에 IPR-처리 마우스로부터 얻은 혈청은 악하선 배양세포의 단백질 합성에는 별 영향을 미치지 못하였으나, DNA합성은 현저하게 증가시켰다. IPR에 의한 악하선 세포의 DNA 합성능의 감소는 propranolol에 의해 차단되지 않았으나 ascorbate에 의해서는 회복되었다. 악하선 배양세포의 DNA 및 단백질 합성을 저해한 IPR의 처리에 의해 배양세포의 EGF분비는 현저히 증가되었다. 이상과 같은 결과는 악하선 세포의 DNA 및 단백질 합성에 작용한 IPR의 효과는 beta-adrenoceptor의 흥분에 의한 것이라기 보다는 IPR로부터 유래된 free radical에 의한 세포독성에 기인함을 시사한다. 따라서 IPR의 생체내 투여에 의한 악하선의 비대화를 보고 한 기존의 결과는 IPR이 악하선에 직접 작용하여 유발된 것이 아닌 다른 경로를 통한 간접적인 효과로 판단될 수 있을 것이다.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.367-373
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• 2013

The ruthenium(II) ferrocenyl heterocyclic thiosemicarbazone complexes of the type $[RuCl(CO)(EPh_3)]_2L$ (where E = P/As; L = binucleating monobasic tridendate thiosemicarbazone ligand) have been investigated. Strutural features were determined by analytical and spectral techniques. Binding of these complexes with CT-DNA by absorption spectral study indicates that the ruthenium(II) complexes form adducts with DNA and has intrinsic binding constant in the range of $3.3{\times}10^4-1.2{\times}10^5M^{-1}$. The complexes exhibit a remarkable DNA cleavage activity with CT-DNA in the presence of hydrogen oxide and the cleavage activity depends on dosage.