• 한국심리학회지 : 문화 및 사회문제
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• 제10권spc호
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• pp.11-28
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• 2004

본 고에서는 청소년이나 청소년기를 어떻게 규정할 것인가의 문제에서 출발하여 기성세대의 청소년관에 대한 부정적 청소년관과 발달심리학의 심리주의적 신화와 부정적 청소년관을 개관하였다. 더불어 활동-환경중심적 입장에서 청소년을 이해해야함을 제안하고, 현대 한국사회에 있어서의 청소년의 가치를 논하였으며, 오늘의 청소년을 어떻게 조망해야 할 것인가에 대한 문제를 논하였다.

• 한국발생생물학회지:발생과생식
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• 제18권3호
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• pp.153-160
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• 2014

Adaptive development of early stage embryo is well established and recently it is explored that the mammalian embryos also have adaptive ability to the stressful environment. However, the mechanisms are largely unknown. In this study, to evaluate the possible role of aquaporin in early embryo developmental adaptation, the expression of aquaporin (AQP) 5 gene which is detected during early development were examined by the environmental condition. To compare expression patterns between in vivo and in vitro, we conducted quantitative RT-PCR and analyzed localization of the AQP5 by whole mount immunofluorescence. At in vivo condition, Aqp5 expressed in oocyte and in all the stages of preimplantation embryo. It showed peak at 2-cell stage and decreased continuously until morula stage. At in vitro condition, Aqp5 expression pattern was similar with in vivo embryos. It expressed both at embryonic genome activation phase and second mid-preimplantation gene activation phase, but the fold changes were modified between in vivo embryos and in vitro embryos. During in vivo development, AQP5 was mainly localized in apical membrane of blastomeres of 4-cell and 8-cell stage embryos, and then it was localized in cytoplasm. However, the main localization area of AQP5 was dramatically shifted after 8-cell stage from cytoplasm to nucleus by in vitro development. Those results explore the modification of Aqp5 expression levels and location of its final products by in vitro culture. It suggests that expression of Aqp5 and the roles of AQP5 in homeostasis can be modulated by in vitro culture, and that early stage embryos can develop successfully by themselves adapting to their condition through modulation of the specific gene expression and localization.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.108-108
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• 2003

The purpose of this is to investigate the effects of vitrification in open pulled straws (OPS) on in vitro survival of porcine embryos. Blastocysts were produced by in vitro fertilization of slaughterhouse-derived, in vitro matured oocytes with frozen-thawed boar semen, and subsequent culture on granulosa cell monolayer. After frozen-thawing, embryos were culture in NCSU-23 medium with 5 mM hypotaurine, 4 mg/$m\ell$ BSA and 10 ng/$m\ell$ for 48 hrs to survival tests. When blastocysts were frozen-thawed by OPS methods, the embryos with normal morphology were 32.1, 34.5 and 38.9 % in early blastocyst, blastocyst and expanded blastocyat stages. The rates of partial damaged embryos were significantly (P<0.05) higher in early biastocysts than expanded blastocysts. In another experiment, the embryos frozen by OPS methods were cultured for 48 hrs for survival and developmental rates in vitro. The proportions of embryos hatched were 11.8, 20.2 and 33.3% in embryos frozen-thawed at stages of early blastocyst, blastocyst and expanded embryos. On the other hand, The proportions of embryo with normal morphology after culture were 23.5, 25.0 and 33.3% in embryos frozen-thawed at stages of early blastocyst, blastocyst and expanded embryos. These finding indicate the possible broader application for OPS methods that this procedure described is relatively harmless, that it can be used for blastocysts of different developmental stages.

• Toxicological Research
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• 제29권4호
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• pp.221-227
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• 2013

Embryonic stem (ES) cells have potential for use in evaluation of developmental toxicity because they are generated in large numbers and differentiate into three germ layers following formation of embryoid bodies (EBs). In earlier study, embryonic stem cell test (EST) was established for assessment of the embryotoxic potential of compounds. Using EBs indicating the onset of differentiation of mouse ES cells, many toxicologists have refined the developmental toxicity of a variety of compounds. However, due to some limitation of the EST method resulting from species-specific differences between humans and mouse, it is an incomplete approach. In this regard, we examined the effects of several developmental toxic chemicals on formation of EBs using human ES cells. Although human ES cells are fastidious in culture and differentiation, we concluded that the relevancy of our experimental method is more accurate than that of EST using mouse ES cells. These types of studies could extend our understanding of how human ES cells could be used for monitoring developmental toxicity and its relevance in relation to its differentiation progress. In addition, this concept will be used as a model system for screening for developmental toxicity of various chemicals. This article might update new information about the usage of embryonic stem cells in the context of their possible ability in the toxicological fields.

• Reproductive and Developmental Biology
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• 제36권4호
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• pp.291-294
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• 2012

Embryonic stem cell classically cultured on feeder layer with FBS contained ES medium. Feeder-free mouse ES cell culture systems are essential to avoid the possible contamination of nonES cells. First we determined the difference between ES cell and MEF by Oct4 population. We demonstrate to culture and to induce differentiation on feeder free condition using a commercially available mouse ES cell lines.

• Reproductive and Developmental Biology
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• 제32권3호
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• pp.167-173
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• 2008

Somatic cells such as oviduct epithelial cell, uterine epithelial cell, cumulus-granulosa cell and buffalo rat river cell has been used to establish an effective culture system for bovine embryos produced in in vitro. But nitric oxide (NO) metabolites secreted from somatic cells were largely arrested the development of bovine in vitro matured/ in vitro fertilized (IVM/IVF) embryos, suggesting that NO was induced the embryonic toxic substance into culture medium. The objective of this study was to investigate whether BOEC co-culture system can ameliorate the NO-mediated oxidative stress in the culture of bovine IVM/IVF embryos. Therefore, we evaluated the developmental rate of bovine IVM/IVF embryos under BOEC co-culture system in the presence or absence of sodium nitroprusside (SNP), as a NO donor, and also detected the expression of growth factor (TGF-$\beta$, EGF and IGFBP) and apoptosis (Caspase-3, Bax and Bcl-2) genes. The supplement of SNP over 5 uM was strongly inhibited blastocyst development of bovine IVM/IVF embryos than in control and 1 uM SNP group (Table 2). The developmental rates beyond morulae stages of bovine IVM/IVF embryos co-cultured with BOEC regardless of SNP supplement (40.4% in 5 uM SNP+ BOEC group and 65.1% in BOEC group) were significantly increased than those of control (35.0%) and SNP single treatment group (23.3%, p<0.05: Table 3). The transcripts of Bax and Caspase-3 genes were detected in all experiment groups (1:Isolated fresh cell (IFC), 2:Primary culture cell (PCC), 3:PCC after using the embryo culture, 4: PCC containing 5 uM SNP and 5: PCC containing 5 uM SNP after using the embryo culture), but Bcl-2 gene was not detected in IFC and PCC (Fig. 1). In the expression of growth factor genes, TGF-$\beta$ gene was found in all experimental groups, and EGF and IGFBP genes were not found in IFC and PCC (Fig. 2). These results indicate that BOEC co-culture system can increase the development beyond morula stages of bovine IVM/IVF embryos, possibly suggesting the alleviation of embryonic toxic substance like nitric oxide.

• 식물조직배양학회지
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• 제22권5호
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• pp.283-290
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• 1995

미나리의 체세포 배발생 조건 및 기작을 구명하고자 배발생 캘러스의 획득에 적합한 시료와 배지를 구명하고 배발달의 과정을 관찰하여 본 결과, 기내 식물체 확보를 위한 미나리의 경정배양은 발생한 줄기 수와 생육상태로 보아 BA가 0.1 - 0.5 mg/L 첨가된 MS배지가 적합하였으며 배발생 캘러스의 발생은 배유와 함께 채취ㆍ배양한 유배를 2,4- D가 1 mg/L 첨가된 배지에서 2 개월간 배양하였을 때 발생하였다. 기내에서 생장한 줄기와 엽병을 배양하였을 경우는 치상후 2과에 엽병의 절단 부위에서 발생한 캘러스는 모두 배발생 캘러스가 아니였으나 치상 후 6 - 8주에 줄기와 엽병의 표피부위에서 발생한 캘러스는 배발생 캘러스이었다. 배발생 캘러스는 계대배양에 의하여 대양 증식이 가능하며 이들은 배발생 캘러스와 비배발생 캘러스를 동시에 형성하였다. 비배발생 캘러스는 다양한 생장조절제를 첨가한 액체 및 고체배지에 반복 및 지체배양하여도 배발생 캘러스로의 분화는 일어나지 않았다. 비배발생 캘러스는 고체배지에 배양하면 쉽게 증식되어 뿌리를 분화하며, 액체배지 에 현탁배양할 경우에는 단세포로 단리되고, 다시 이들은 작은 원형세포괴를 형성한 후 단지 뿌리만을 발생하였다.

• 한국가축번식학회지
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• 제20권2호
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• pp.191-196
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• 1996

The objective of this study were to investigate the effects of culture media and additives on the development of bovine in vitro matured(IVM) and in vitro fertilized(IVF) oocytes. In experiment 1, bovine oocytes were cultured in droplets of TC 199 supplemented with 10% fetal bovine serum(FBS) with or without hormones (5$\mu\textrm{g}$/ml FSH, 5$\mu\textrm{g}$/ml LH, 1$\mu\textrm{g}$/ml E2). Cleavage rates of embryos cultured for 40~44hrs after IVF were higher when embryos were cultured in TC 199 supplemented hormones (68.1%, 921/35) than without hormones (52.7%, 77/146), but the percentages of development beyond morulae stage were not difference (20.7%, 19.4%). In experiment 2, the effects of various media such as TC 199, synthetic oviduct fluid(SOF), CR1aa with different energy source (fatal bovine serum, FBS; bovine serum albumin, BSA) on developmental capacity of IVM/IVF bovine embryos were investigated. The developmental rates into morulae and blastocysts were 27.1, 10.7, 6.3 and 0%, respecitvely, in CR1aa plus 3mg/ml BSA, SOF plus 10% FBS, TC 199 plus 10% FBS, SOF plus 3mg/ml BSA. In experiment 3, the comparisons of bovine embryos developed to morulae and blastocysts in different culture media (TC 199, SOF, CR1aa, Menezo's B2) were investigated. The developmental capacity beyond morulae stage were 32.9, 26.6, 11.1 and 7.1%, respectively, in Menezo's B2 plus BSA, CR1aa plus BSA, SOF plus BSA, TC 199 plus FBS medium. The cell numbers of the blastocyst were not different in different cultrue media. In experiment 4, bovine embryos were co-cultured with vobine oviduct epithelial cells(BOEC) in TC 199 plus FBS, SOF plus BSA, CR1aa plus BSA, Menezo's B2 plus BSA. The morula and blastocyst rates were 44.7, 32.9, 26.0 and 23.3%, respectively, in CR1aa TC 199, SOF, and Menezo's B2 medium. The cell numbers of the blastocyst were similar to those of blastocyst developed in different culture media.

• 대한수의학회지
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• 제38권2호
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• pp.394-400
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• 1998

Cryopreservation of embryos by vitrification is a simple method to preserve bovine embryos for subsequent embryo transfer, but embryonic viability after vitrification has been inconsistent and low compared with conventional slow freezing. The aim of the present study is to examine the effect of serum or serum albumin in a vitrification solution and epidermal growth factor(EGF) or fibroblast growth factor(FGF) on in vitro viability of bovine blastocysts frozen by vitrification. Bovine blastocysts were produced by in vitro maturation, fertilization of follicular oocytes and culture of embryos in a synthetic oviduct fluid medium(SOFM) containing BSA and 19 essential and nonessential amino acids. Blastocysts with excellent or good morphology were selected at 7 or 8 days after culture and utilized for vitrification. In experiment 1, blastocysts were vitrified in a solution containing semi-fetal calf serum(SFCS) or BSA(5 or 10mg/ml) and then their subsequent viabilities were examined by culturing thawed embryos in a SOFM containing BSA and 19 amino acids. Effect of EGF or FGF added to a SOFM containing polyvinyl alcohol(PVA) on the viability of vitrified-thawed blastocysts was investigated in experiment 2. BSA added at 5 or 10mg/ml to a vitrification solution showed significantly higher(p < 0.05) developmental rate to expanded and hatching blastocysts than SFCS, but there was no significant difference in the developmental rate to hatched blastocysts after thawing. Supplementation of a culture medium with EGF and/or FGF significantly increased(p < 0.05) embryo development to expanded blastocysts compared with control but showed no beneficial effect on the development to hatching or hatched blastocysts. Coculture of thawed embryos with granulosa cells in a TCM 199 containing 10% fetal calf serum(FCS) showed the highest developmental rate to expanded, hatching and hatched blastocysts among the groups tested. In conclusion, supplementation of a vitrification solution with BSA at 5mg/ml and culture of thawed blastocysts in a medium containing EGF and/or FGF can improve in vitro viability of bovine blastocysts frozen by vitrification.

• 한국동물생명공학회지
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• 제37권1호
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• pp.34-41
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• 2022

In vivo oocytes grow and mature in ovarian follicles whereas oocytes are matured in vitro in plastic culture dishes with a hard surface. In vivo oocytes show a superior developmental ability to in vitro counterparts, indicating suboptimal environments of in vitro culture. This study aimed to evaluate the influence of an agarose matrix as a culture substrate during in vitro maturation (IVM) on the development of pig oocytes derived from small antral follicles (SAFs). Cumulus-oocyte complexes (COCs) retrieved from SAFs were grown in a plastic culture dish without an agarose matrix and then cultured for maturation in a plastic dish coated without (control) or with a 1% or 2% (w/v) agarose hydrogel. Then, the effect of the soft agarose matrix on oocyte maturation and embryonic development was assessed by analyzing intra-oocyte contents of glutathione (GSH) and reactive oxygen species (ROS), expression of VEGFA, HIF1A, and PFKP genes, and blastocyst formation after parthenogenesis. IVM of pig COCs on a 1% (w/v) agarose matrix showed a significantly higher blastocyst formation, intra-oocyte GSH contents, and transcript abundance of VEGFA. Moreover, a significantly lower intra-oocyte ROS content was detected in oocytes matured on the 1% and 2% (w/v) agarose matrices than in control. Our results demonstrated that IVM of SAFs-derived pig oocytes on a soft agarose matrix enhanced developmental ability by improving the cytoplasmic maturation of oocytes through redox balancing and regulation of gene expression.