• Journal of Embryo Transfer
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• v.28 no.1
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• pp.1-6
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• 2013

A lot of works have been dedicated to clarify the reasons why the establishment of embryonic stem cells (ESCs) from pig is more difficult than that from mouse and human. Several concomitant factors such as culture condition including feeder layer, sensitivity of cell to cell contact, definitive markers of pluripotency for evaluation of the validity and optimal timing of derivation have been suggested as the disturbing factors in the establishment of porcine ESCs Traditionally, attempts to derive stem cells from porcine embryos have depend on protocols established for mouse ESCs using inner cell mass (ICM) for the isolation and culture. And more recently, protocols used for primate ESCs were also applied. However, there is no report for the establishment of porcine ESCs. Indeed, ungulate species including pigs have crucial developmental differences unlike rodents and primates. Here we will review recent studies about issues for establishment of porcine ESCs and discuss the promise and strategies focusing on the timing for derivation and pluripotent state of porcine ESCs.

• Clinical and Experimental Reproductive Medicine
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• v.51 no.1
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• pp.57-62
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• 2024

Objective: The purpose of this study was to use a mouse model to investigate the blastocyst formation rate in vitrified-warmed embryos derived from vitrified-warmed oocytes. Methods: Metaphase II oocytes obtained from BDF1 mice were vitrified and warmed, followed by fertilization with epididymal sperm. On day 3, a total of 176 embryos, at either the eight-cell or the morula stage, were vitrified-warmed (representing group 1). For group 2, 155 embryos at the same developmental stages were not vitrified, but rather were directly cultured until day 5. Finally, group 3 included day-5 blastocysts derived from fresh oocytes, which served as fresh controls. The primary outcome measured was the rate of blastocyst formation per day-3 embryo at the eight-cell or morula stage. Results: The rates of blastocyst formation per day-3 embryo were comparable between groups 1 and 2, at 64.5% and 69.7%, respectively (p>0.05). The formation rates of good-quality blastocysts (expanded, hatching, or hatched) were also similar for groups 1 and 2, at 35.5% and 43.2%, respectively (p>0.05). For the fresh oocytes (group 3), the blastocyst formation rate was 75.5%, which was similar to groups 1 and 2. However, the rate of good-quality blastocyst formation in group 3 was 57.3%, significantly exceeding those of group 1 (p=0.001) and group 2 (p=0.023). Conclusion: Regarding developmental potential to the blastocyst stage, vitrified-warmed day-3 embryos originating from vitrified-warmed oocytes demonstrated comparable results to non-vitrified embryos from similar oocytes. These findings indicate that day-3 embryos derived from vitrified-warmed oocytes can be effectively cryopreserved without incurring cellular damage.

• BMB Reports
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• v.34 no.3
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• pp.206-211
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• 2001

Endostatin, a proteolytic fragment of collagen XVIII, is a potent inhibitor of angiogenesis and the growth of several primary tumors. However, the opinions on the activity of endostatin derivatives deleted N- or C- terminal are still controversial. In this regard, we produced mouse endostatin and its derivatives in the prokaryotic system, and studied their anti-tumor activity. The [$^3H$]-thymidine incorporation assay demonstrated that N-terminal deleted mouse endostatin, and a C- and N-terminal deleted mutant, effectively inhibited the proliferation of human umbilical vein endothelial cells (HUVECs). The biological activity of endostatin was also shown by its in vivo anti-angiogenic ability on the chorioallantoic membrane (CAM) of a chick embryo. Treatment of $200\;{\mu}g$ of mouse endostatin, or N-terminal deleted mouse endostatin, inhibited capillary formation of CAM 45 to 71%, which is comparative to a 80% effect of positive control, $1\;{\mu}g$ of retinoic acid. An in vivo mouse tumor growth assay showed that N-terminal deleted mouse endostatin, and the N-/C-terminal deleted mutant, significantly repressed the growth of B16F10 melanoma cells in mice as did the full-length mouse endostatin. According to these results, N-and N-/C-terminal deleted mouse endostatins are the potent inhibitors of tumor growth and angiogenesis.

• Journal of Embryo Transfer
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• v.4 no.1
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• pp.1-13
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• 1989

This paper reviews the most important steps that have generated consistent progress in principles and developmental progress of embryo cryopreservation, and also study on freezing procedure and its application by conventional method and current improved method for freezing procedure and its appilcation of embryo cryopreservation in farm animals. Four were of particular interest: 1.The transport of water across the ccli membrane (zona pellucida) during freezing and thawing accordinglyplays a role in determing whether the celi survives. This movement of water is controlied mainly by extracellular phase changes and by the nature and concentration of any cryoprotective agent present. Therates of cooling, freezing and warming, and the intervals over which they are applied are further decisi've factors in determining whether a cryopreservation procedure allows survival after thawing. 2.The first successful deep freezing experiments with sheep morula and blastocysts during the seventies were based on the early procedures used for mouse embryos.Current research during the eighties is developed with the aim of simplifying and improving current procedures such as one-step dilution and rapid or ultra-rapid cooling by using the model of laboratory animals. 3.The conventional method for the embryo cryopreservation is described. An alternative to this method which may result in high survival and also in reducing of the freezing and thawing time is done by combing a permeable cryoprotectant such as glycerol, DMSO or propanediol and a non-permeable compound such as sucrose, trehalose, raffinose or lactose. 4.Finally a different approach to the preservation of embryos, named vitrification, is introduced. This procedure depends upon the ability of concentrated solutions of cryoprotective agents such as glycerol and propanediol to supercool to very low temperature (-196$^{\circ}C$) during rapid cooling before solidifying without formation of ice. However, more complete data are necessary for successful vitrification of blastocysts.

• Clinical and Experimental Reproductive Medicine
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• v.19 no.2
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• pp.117-123
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• 1992

Development in vitro of 2-cell mouse embryos was examined after appropriate exposure to oviductal milieu to demonstrate biological activity present in the oviducts. ICR and ($C57Bl/6{\times}Balb/c$) $F_1$ hybrid mice were superovulated and mated for the recovery of early embryos. Embryos were recoverd at every 2h intervals from 32h post-hCG(hph) to 56 hph. The proportions of developmental stages were determined in the recovered embryos. Development in vitro of 2-cell embryos was more rapid in $F_1$ hybrid than in ICR, showing high proportions of 4-cell embryo and blastocyst at 120 hph. 100% of blastocyst development was obtained at 38hph in $F_1$ hybrid and at 50 hph in ICR when 2-cell embryos were cultured upto 120hph in vitro. Moreover, in vitro culture of oviducts containing 2-cell embryos in ICR mice for 12h from 34hph to 46hph increased developmental capacity of ICR mouse embryo in vitro. The results indicate that oviductal environment contains substances having mitogenic activity and overcoming early cell block in vitro. The mitogenic activity is effective in vitro as well as in vivo.

• Journal of Embryo Transfer
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• v.26 no.2
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• pp.135-140
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• 2011

Genistein is a product of naturally occurring isoflavones at relatively high levels in soybeans. The harmful effects of ethanol are attributed to the induction of biological processes which lead to an increase in the generation of reactive oxygen species in fetuses. In this study, we investigated the effects of genistein ($1{\times}10^{-8}$ and $1{\times}10^{-7}\;{\mu}g$/ml) on gene expressions of the representative cellular antioxidative enzymes in ethanol (1 ${\mu}l$/ml)-treated mouse fetuses during the critical period (embryonic days 8.5~10.5) of organogenesis using a semi-quantitative RT-PCR analysis. The mRNA levels of cytosolic glutathione peroxidase (GPx), phospholipid hydroperoxide GPx, cytosolic CU,Zn-superoxide dismutase (SOD), and mitochondrial SOD were significantly decreased in ethanol-treated fetuses. However, the mRNA levels of ethanol plus genistein-treated fetuses were significantly higher than those of ethanol alone fetuses. These results indicate that genistein can up-regulate the expressions of GPx and SOD mRNAs reduced by the ethanol treatment in fetuses.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6341-6345
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• 2013

To clarify the role of stem cells in hepatocarcinogenesis, glypican-3 (GPC-3) and E-cadherin expression was investigated in embryonic cell lineages. Mouse embryonic stem cells (ESCs), hepatic progenitor cells (HPCs) and hepatocyte like cells (HCs), representing 0, 22 and 40 days of differentiation, respectively, were treated in vitro with diethylnitrosamine (DEN) at four doses (0, 1, 5 and 15 mM; G1, G2, G3 and G4, respectively) for 24 h and GPC-3 and E-cadherin expression was examined by relative quantitative real-time PCR and immunocytochemistry. GPC-3 mRNA expression was significantly different for G4 at day 0 (p<0.001) and for G4 at day 22 (p<0.01) compared with the control (G1). E-cadherin mRNA expression was significantly different for G3 and G4 at day 0 (p<0.05 and p<0.001, respectively), for G2 and G4 (p<0.05 and p<0.001, respectively) at day 22 and for G2 and G4 (p<0.01 and p<0.001, respectively) at day 40 compared with G1. Immunofluorescence staining for GPC-3 showed a membranous and/or granular expression in cytoplasm of ESCs and HPCs and granular and/or diffuse expression in cytoplasm of HCs, which were also stained by E-cadherin. DEN treatment increased GPC-3 expression in ESCs, HPCs and HCs, with increase of E-cadherin expression. Taken together, the expression of GPC-3 was altered by DEN treatment. However, its expression pattern was different at the stage of embryo stem cells and its derived hepatic lineage cells. This suggests that GPC-3 expression may be modulated in the progeny of stem cells during their differentiation toward hepatocytes, associated with E-cadherin expression.

• Journal of Embryo Transfer
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• v.21 no.1
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• pp.53-58
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• 2006

This study was conducted to comparing on vitrification of mouse oocytes and embryos using CPS, conventional straws and CPS by evaluating in morphological survival for oocytes, and embryonic cleavages and blastocyst formation for embryos. The morphological survival in vitro after thawing of vitrified oocytes using CPS (75%) and conventional straws (72%) were significantly higher (p<0.05) than that using OPS (68%). The blastocyst formation rates of vitrified embryos using CPS (48.6%) and unfrozen control embryos (56.0%) were significantly higher (p<0.05) than those of conventional straws (43.4%) and OPS (37.7%). The rates of morula formation were also higher to control, CPS, conventional straws and OPS in orderly. These results show that CPS has the advantages of achieving a high survival and safety preservation.

• Clinical and Experimental Reproductive Medicine
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• v.41 no.1
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• pp.1-8
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• 2014

Objective: Estrogen related receptor ${\beta}$ (Esrrb) is a member of the orphan nuclear receptors and may regulate the expression of pluripotencyrelated genes, such as Oct4 and Nanog. Therefore, in the present study, we have developed a method for delivering exogenous ESRRB recombinant protein into embryos by using cell-penetrating peptide (CPP) conjugation and have analyzed their effect on embryonic development. Methods: Mouse oocytes and embryos were obtained from superovulated mice. The expression of Oct4 mRNA and the cell number of inner cell mass (ICM) in the in vitro-derived and in vivo-derived blastocysts were first analyzed by real time-reverse transcription-polymerase chain reaction and differential staining. Then 8-cell embryos were cultured in KSOM media with or without $2{\mu}g/mL$ CPP-ESRRB protein for 24 to 48 hours, followed by checking their integration into embryos during in vitro culture by Western blot and immunocytochemistry. Results: Expression of Oct4 and the cell number of ICM were lower in the in vitro-derived blastocysts than in the in vivo-derived ones (p<0.05). In the blastocysts derived from the CPP-ESRRB-treated group, expression of Oct4 was greater than in the non-treated groups (p<0.05). Although no difference in embryonic development was observed between the treated and non-treated groups, the cell number of ICM was greater in the CPP-ESRRB-treated group. Conclusion: Treatment of CPP-ESRRB during cultivation could increase embryos' expression of Oct4 and the formation rate of the ICM in the blastocyst. Additionally, an exogenous delivery system of CPP-conjugated protein would be a useful tool for improving embryo culture systems.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.1
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• pp.21-26
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• 1997

This study was undertaken to examine the expression of EGF-R protein on ICM obtained from mouse IVF/IVC blastocyst by immunosurgery and indirect immunofluorescence(IIF). ICM cells used for this experiment were obtained from immunosurgery of mouse blatstocysts produced at 96 h after IVF, and recovered ICMs were assayed for cell viability and expression of EGF-R. The results obtained in this experiment were summarized as follows: when blastocysts were exposed to rabbit anti-mouse serum (antiserum) for 15-30 min. and then transferred them to guinea pig serum (complement) for 15-60 min., recovery rates of isolated ICMs were 8.0-84.2%. Especially, the best recovery (84.2%) of ICMs was obtained when exposure time to antiserum and complement was 30 min. and 60 min., respectively. In addition, when viability of isolated ICMs after immunosurgery was assessed by live/dead staining method, in all groups viability (93.8-100.0%) of isolated ICMs were not damaged if separated from TE cell. Also, we detected the expression of EGF-R on ICM cell by IIF. Therefore, these results suggest that EGF-R expression on the ICMs can stimulate the higher usablity of exogenous EGF to improve the preimplantation embryo development in vitro.