• Korean Journal of Animal Reproduction
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• v.22 no.3
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• pp.253-264
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• 1998

Porcine follicular oocyte, collected from antral follicles (2~5 mm in diameter) of gilt ovaries were matured in vitro porcine follicular fluid (pFF) with PMSG (pFF-PMSG) buffer with at 37$^{\circ}C$ under 5% CO2 in air their ability of maturation promoting factor (MPF), of GV and GVBD formation was examined followed during time after in vitro culture. Formation of second metaphase was observed in 57.6% and 71.2% of matured in with pFF-PMSG buffer to 45 and 50 hours after invitro. Porcine oocytes cultured in pFF-PMSG for various periods of up to 30 hours were stained with Hoechst-33342 and classified according to maturation before assaying. Histone H1 kinase (H1K) activity was assayed during meiotic maturation in porcine oocytes matured in pFF-PMSG buffer in vitro. In oocytes matured in pFF-PMSG, H1K activity was at the 30 hours after culture and increased about 15 fold than at the germinal vesicle stage with before at the cultured in vitro. This pattern is similar to those reported in non-mammalian species and su, pp.rts the concepts that H1K is ubiquitous in eukaryotes and controls the meiotic cell cycle in mammals. These results suggest that the maturation pFF-PMSG buffer used influences the fluctuation pattern of H1K activity and biological characteristics of porcine oocytes cultured in vitro.

• Proceedings of the KSAR Conference
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• 2001.10a
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• pp.18-24
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• 2001

To identify genes implicated in the control of pluripotency as well as characteristics of stem cells, we analyzed expression profiles of genes derived from mouse morulas, blastocysts, embryonic stem cells, mesenchymal stem cells, and uterus tissue using cDNA microarray. Comparative analyses of their expression profiles identified putative clones that expressed specifically in specific samples or not in a specific sample. The expression pattern of these candidate clones was analyzed using RT-PCR and non-radioactive in situ hybridization. Functional annotation of these clones on pluripotency and stem cell plasticity is in ongoing. These studies may further our understanding on the nature of the stem cells and molecular mechanisms underlying many facets of mammalian development and differentiation.

• Journal of Food Hygiene and Safety
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• v.11 no.1
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• pp.41-50
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• 1996

The yields of solvent fraction of irradiated red ginseng powder were increased in the order of petroleum ether(PE)

• Molecules and Cells
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• v.22 no.2
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• pp.203-209
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• 2006

TBP (TATA-binding protein)-related factor 2 (TRF2) regulates transcription during a nuber of cellular processes. We previously demonstrated that it is localized in the cytoplasm and is translocated to the nucleus by DNA-damaging agents. However, the cytoplasmic localization of TRF2 is controversial. In this study, we reconfirmed its cytoplasmic localization in various ways and examined its nuclear migration. Stresses such as heat shock, redox agents, heavy metals, and osmotic shock did not affect localization whereas genotoxins such as methyl methanesulfonate (MMS), cisplatin, etoposide, and hydroxyurea caused it to migrate to the nucleus. Adriamycin, mitomycin C and ${\gamma}$-rays had no obvious effect. We determined optimal conditions for the nuclear migration. The proportions of cells with nuclei enriched for TRF2 were 25-60% and 5-10% for stressed cells and control cells, respectively. Nuclear translocation was observed after 1 h, 4 h and 12 h for cisplatin, etoposide and MMS and hydroxyurea, respectively. The association of TRF2 with the chromatin and promoter region of the proliferating cell nuclear antigen (PCNA) gene, a putative target of TRF2, was increased by MMS treatment. Thus TRF2 may be involved in genotoxin-induced transcriptional regulation.

• Molecules and Cells
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• v.22 no.1
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• pp.113-118
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• 2006

Thioredoxin reductase (TrxR), a component of the redox control system involving thioredoxin (Trx), is implicated in defense against oxidative stress, control of cell growth and proliferation, and regulation of apoptosis. In the present study a stable transfectant was made by introducing the vector pcDNA3.0 harboring the fission yeast TrxR gene into COS-7 African green monkey kidney fibroblast cells. The exogenous TrxR gene led to an increase in TrxR activity of up to 3.2-fold but did not affect glutathione (GSH) content, or glutaredoxin and caspase-3 activities. Levels of reactive oxygen species (ROS), but not those of nitric oxide (NO), were reduced. Conversely, 1-chloro-2,4-dinitrobezene (CDNB), an irreversible inhibitor of mammalian TrxR, enhanced ROS levels in the COS-7 cells. After treatment with hydrogen peroxide, the level of intracellular ROS was lower in the transfectants than in the vector control cells. These results confirm that TrxR is a crucial determinant of the level of cellular ROS during oxidative stress as well as in the normal state.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.3
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• pp.107-114
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• 2013

Homeobox genes play essential roles in embryonic development and reproduction. Recently, a large cluster of homeobox genes, reproductive homeobox genes on the X chromosome (Rhox) genes, was discovered as three gene clusters, ${\alpha}$, ${\beta}$, and ${\gamma}$ in mice. It was found that Rhox genes were selectively expressed in reproduction-associated tissues, such as those of the testes, epididymis, ovaries, and placenta. Hence, it was proposed that Rhox genes are important for regulating various reproductive features, especially gametogenesis in male as well as in female mammals. It was first determined that 12 Rhox genes are clustered into ${\alpha}$ (Rhox1-4), ${\beta}$ (Rhox5-9), and ${\gamma}$ (Rhox10-12) subclusters, and recently Rhox13 has also been found. At present, 33 Rhox genes have been identified in the mouse genome, 11 in the rat, and three in the human. Rhox genes are also responsible for embryonic development, with considerable amounts of Rhox expression in trophoblasts, placenta tissue, embryonic stem cells, and primordial germ cells. In this article we summarized the current understanding of Rhox family genes involved in reproduction and embryonic development and elucidated a previously unreported cell-specific expression in ovarian cells.

• YAKHAK HOEJI
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• v.55 no.3
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• pp.251-259
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• 2011

Cigarette smoke condensate (CSC) is known to be carcinogenic compound. CSC contains many organic compounds such as polycyclic aromatic hydrocarbons (PAHs), and heterocyclic amine compounds (HCAs). Reactive oxygen species (ROS) are also generated and induce oxidative DNA damage during the metabolism of CSC. The rat microsome mediated and DNA repair enzyme treated comet assays together with conventional comet assay were performed to evaluate the mechanisms of CSC genotoxicity. The organic extract of CSC induced oxidative and microsome mediated DNA damage. Vitamin C as a model antioxidant reduced DNA damage in endonuclease III treated comet assay. One of flavonoid, galangin as a CYP1A1 inhibitor, reduced DNA damage in the presence of S-9 mixture. The ethanol extracts of the mixed vegetables (BV) or the mixed fruits (BF) showed potent inhibitory effects against CSC induced DNA damage with oxidative DNA lesions and in the prescence of S-9 mixture. These results indicate that BV and BF could prevent CSC-induced cellular DNA damage by inhibiting oxidative stress and suppressing cytochrome P450 in mammalian cells.

• 대한생식의학회:학술대회논문집
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• 2002.05a
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• pp.11-17
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• 2002

Animal clones derived from somatic cells have been successfully produced in a variety of mammalian species such as sheep, cattle, mice, goats, pigs, cat and rabbits. However, there are still many unsolved problems in the present cloning technology. Somatic cell nuclear transfer has shown several developmental aberrancies including high rate of abortion in early gestation and increased perinatal death. These developmental failures of cloned embryos may arise from abnormal reprogramming of donor genome and/or incomplete cloning procedure. We have found that overall genomic methylation status of cloned bovine embryos is quite different from that of normal embryos in various genomic regions, suggesting that the developmental failures of cloned embryos may be due to incomplete reprogramming of donor genomic DNA. Many of the advances in understanding the molecular events for reprogramming of donor genome will more clarify the developmental defects of cloned embryos.

• PNF and Movement
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• v.6 no.3
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• pp.37-51
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• 2008

Purpose : This paper focuses on the emerging concept that adult central nervous system neurogenesis can be regulated by various physical activity, enriched environment, and pathological conditions. Neurogenesis-the production of new neuron-is an ongoing process that persists in the adult brain of mammalian, including humans. Result : The adult brain was thought be limited in its regenerative function. However, this concepts changed, recent evidence of neurogenesis in certain adult brain areas such as SVZ(subventricular zone) and SGZ(subgranular zone) in hippocampus, raised possibility for improved treatment for patient with stroke. Neural plasticity has an adaptive purpose, because an ability of the brain to change in response to peripheral stimulation, physical activity, experience, and injury. Conclusions : The major function of the neurogenesis in adult brain seems to be replacing the neuron that die regularly in discrete adult brain regions. These cells are capable of functionally integrating into neighboring neural cells, and reconnecting to the correct neural networks. This review suggest that various intervention, including physical activity, voluntary movement training, skilled forelimb reaching training, and enriched environment, induced neural cell production in certain adult brain, and associated with functional recovery after stroke.

• The Korean Journal of Zoology
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• v.22 no.4
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• pp.141-152
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• 1979

Feline leukemia virus DNA polymerase was purified by ion-exchange and nucleic acid affinity chromatographies. The enzyme consists of a single polypeptide chain of approximately 72, 000 molecular weight as determined by both of a glycerol density gradient centrifugation and SDS-polyacrylamide gel electrophoresis. The preferred divalent cation for DNA synthesis is $Mn^2+$ on a variety of template-primers, and its optimum concentration appears to be significantly lower than reported results of other mammalian type-C viral enzymes. The divalent cation requirement for maximum activity of RNase H is similar to those of DNA polymerase. Both DNA polymerase and RNase H activities appear to reside on the same molecule as demonstrated by the copurification of both activities through various purification steps. An additional RNase H without detectible polymerase activity was generated by a limited chymotrypsin digestion. This RNase H activity was inhibited equally effectively as RNase H in the intact reverse transcriptase by antisera prepared against reverse transcriptase of feline leukemia virus. Neutralization and binding test showed that antibody binding to reverse transcriptase molecule did not completely inhibit the polymerase activity.