• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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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.

• Clinical and Experimental Reproductive Medicine
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• 제46권4호
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• pp.189-196
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• 2019

Objective: We aimed to evaluate the effects of different oxygen conditions (20% [high O₂], 5% [low O₂] and 5% decreased to 2% [dynamic O₂]) on mouse pre- and peri-implantation development using a novel double-channel gas supply (DCGS) incubator (CNC Biotech Inc.) to alter the oxygen concentration during in vitro culture. Methods: The high-O₂ and low-O₂ groups were cultured from the one-cell to the blastocyst stage under 20% and 5% oxygen concentrations, respectively. In the dynamic-O₂ group, mouse embryos were cultured from the one-cell to the morula stage under 5% O₂ for 3 days, followed by culture under 2% O₂ to the blastocyst stage. To evaluate peri-implantation development, the blastocysts from the three groups were individually transferred to a fibronectin-coated dish and cultured to the outgrowth stage in droplets. Results: The blastocyst formation rate was significantly higher in the low-O₂ and dynamic-O₂ groups than in the high-O₂ group. The total cell number was significantly higher in the dynamic-O₂ group than in the low-O₂ and high-O₂ groups. Additionally, the apoptotic index was significantly lower in the low-O₂ and dynamic-O₂ groups than in the high-O₂ group. The trophoblast outgrowth rate and spread area were significantly higher in the low-O₂ and dynamic-O₂ groups than in the high-O₂ group. Conclusion: Our results showed that a dynamic oxygen concentration (decreasing from 5% to 2%) had beneficial effects on mouse pre- and peri-implantation development. Optimized, dynamic changing of oxygen concentrations using the novel DCGS incubator could improve the developmental competence of in vitro cultured embryos in a human in vitro fertilization and embryo transfer program.

• Molecules and Cells
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• 제24권3호
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• pp.409-415
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• 2007

The retinoblastoma (Rb) gene is one of the most important genes in cell cycle regulation and tumorigenesis. Homozygosity for a germ-line Rb mutation results in embryonic lethality and evokes developmental defects associated with inappropriate S-phase entry and high levels of apoptosis. Although Rb has been extensively studied, more target genes need to be identified and characterized to unravel the precise mechanism of Rb function. In order to identify Rb-regulated genes, we analyzed the gene expression profile of Rb-deficient mouse embryo fibroblasts (MEFs), and identified an unknown gene, RbEST47, that is transcriptionally upregulated in Rb-deficient MEFs. This gene is conserved from fruitfly to human. It is expressed in brain, lung, kidney, and testis, and is located on mouse chromosome 2. This region is syntenic to human chromosome 9q34.3, which frequently exhibits loss of heterozygosity in neoplastic diseases. RbEST47 was considerably down-regulated in immortalized cells, and showed cell cycle-dependent expression, suggesting important roles in S and/or G2.

• Clinical and Experimental Reproductive Medicine
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• 제18권1호
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• pp.35-40
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• 1991

To find out the suitable method for blastomeres fusion of mouse 2-cell embryo using electric stimuli, these studies were carried out with various voltages (1.0 KV, 1.2 KV, 1.5 KV, 1.7 KV and 2.0KV), pulse duration times($50{\mu}\;sec$, $75/{\mu}\;sec$, $100{\mu}\;sec$) and different fusion solutions. In addition, the fused embryos were cultured for 72-80hr to observe their subsequent development. These results were summarized as follows: 1. The proportion of the fused embryos were 50.8%(34/67), 60.7%(34/56), 70.6%(48/68), 66.7% (48/72) and 85.3% (58/68) after stimuli of 1.0KV, 1.2KV, 1.5KV, 1.7KV and 2.0KV for $100{\mu}\;sec$ with 2 times, and the electric stimulation at 2.0KV(85.3%) was the most effective voltage on the blastomere fusion. 2. For in vitro development, blastocysts of the fused embryos were cultured for 72-80hrs in $M_{16}$ medium. The group(52.1%) treated with 1.5KV for $100{\mu}\;sec$ with 2 times showd higher development rates than those any other group. However, these results were not corresponded to those of the rates of blastomere fusion. 3. There were no significant differences among the rates of blastomeres fusion to 50(70.6%), 75(71.9%), and 100(78.0%) ${\mu}sec$ stimulation at 1.5KV with two times. However, the development rates of the fused embryo in vitro were 52.1%(25/48), 28.3%(13/46) and 9.4%(3/32) at the above conditions, and the development rates of fused embryo increased as the pulse duration times increased. 4. The rates of the blastomeres fusion were 38.9% (28/72) or 70.6% (48/68) in electrolyte (PBS) or non-electrolyte(0.3M mannitol) solution. The development rates of the fused embryo were 32.1% (9/28) or 52.1%(25/48) in the above fusion solutions, and non-electrolyte-treated group showed higher development rates of embryo than that of electrolyte-treated group.

• Animal cells and systems
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• 제10권1호
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• pp.41-47
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• 2006

Development of the mammalian pre-implantation embryos has unique features, such as a slow and unsynchronized cell division, compaction, and eventual formation of blastocysts with inner cell mass and trophectoderm. In order to have a clue on molecular mechanisms that reside in mouse early development, we suppressed expression of early embryo-specific genes with RNAi and observed their development in vitro. We observed developmental defects in embryos microinjected with dsRNAs for Oct4 or Nanog among the tested genes. Careful examinations revealed that development of the most of the Oct4- or Nanog-suppressed embryos were arrested at the morula stage. These results suggest that the Oct4 and Nanog activities are also required for embryogenesis earlier than the blastocyst stage.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.96-96
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• 2003

Nek2 (NIMA-related protein) is a mammalian cell cycle-regulated kinase that involves in chromosome condensation and centrosome regulation and NuMA (nuclear mitotic apparatus protein) is involved in spindle assembly during a cell cycle. The cellular distribution and organization of the centrosomal components is completely unknown during fertilization and embryonic development. We examined distribution of two well-known centrosomal proteins, Nek2 and NuMA in mouse gametes and embryos to get an insight in the reorganization of centrosomal proteins during germ cell development and early fertilization. Spermatogenic cells, gametes, and embryos were analyzed with anti-Nek2 or -NuMA antibodies by immunological assay, RT-PCR, and overexpression through gene transfection. Mitotically or meiotically active spermatogenic cells were intensively stained with these antibodies in both centrosomes and cytoplasm, whereas the oocytes showed different staining patterns depending on the meiotic stages. During maturation, GV, GVBD, and MI stage were clearly stained with NuMA antibody in the nucleus or cytoplasm at MII. Also, Nek2 was detectable in cytoplasm as scattered spots or chromosome associated at MII. In early developmental embryo, NuMA was detected in nucleus of each blastomere, while Nek2 was detected in cytoplasm. In contrast to previously reported results, Nek2 and NuMA were detected in both decondensing head, and the centriole of demembranated and decondensed sperm or whole body of trypsin-treated sperm for Nek2. During meiotic progress in oocytes, transcripts levels were the highest in MI stage and then downregulated in MII. Also, it shows dramatically change in early developmental embryos, firstly, it was increased until 4 cell stage and reduced in 8 cell stage, and finally, transcript levels were upregulated until blastoscyst. This finding suggests that cnetrosomal component may play an important role in reorganizing of functional centrosome during fertilization process and subsequent development.

• Clinical and Experimental Reproductive Medicine
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• 제30권1호
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• pp.5-14
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• 2003

Objective: Present study was aimed to verify the effect of granulocyte macrophage-colony stimulating factor (GM-CSF) in the preimplantation development of mouse embryos and the involvement of the mitogen activated protein kiase (MAPK) in the GM-CSF signaling. Methods: Two-cell embryos were cultured for 96 h in the presence or absence of GM-CSF (0, 0.4, 2, 10 ng/ml) and PD98059, a MEK inhibitor (10 ${\mu}M$). Morphological development, cell number per blastocyst, and apoptotic nuclei, were eamined. MAPK activity of embryonic immunoprecipitate by MAPK (ERK1/2) antibody was measured by in vitro phosphorylation of myelin basic protein. Results: At post hCG 122 h the embryonic development among the experimental groups was significantly different (p=0.018). The rate of blastocyst development and cell number per embryo were the highest in 2 ng/ml GM-CSF treatment group. The percent of apoptotic cells of the GM-CSF-treated embryos was the lowest among the group. In blastocysts, GM-CSF treatment transiently increased MAPK activity. PD098059 attenuated the effect of GM-CSF on the morphological development, increase in cell number per blastocyst, down regulation of apoptosis, and upregulation of MAPK activity, suggesting that activation of MAPK cascade possibly mediated the embryotropic effect of GM-CSF. Conclusion: This result suggested that GM-CSF potentiated the development of preimplantation mouse embryos by activation of MAPK.

• 한국가축번식학회지
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• 제8권2호
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• pp.110-115
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• 1984

These experiments were carried out to obtain the information about the optimal pH osmolality affecting in vitro fertilization of the mouse eggs, to elucidate the 2-cell block to development in vitro and to find out the method of controlling the subsequent embryo development in vitro. pH and osomlality was adjusted by adding NaCl or NaHCO3 to the basic salt solution. In vitro fertilization were carried out by inroducting the cumulus masses to the suspension of epididymal spermatozoa at each pH, osmolality, and 10${\mu}$M-EDTA medium. The results obtained in these experiments were summarized as follows: 1. The fertilization rates in vitro at each medium of 235, 252, 269, 286, 306, 323, 345, 368, 393 mosmol were 15.6, 38.2, 65.7, 75.6, 80.9, 74.3, 58.1, 35.1, 24.3, 11.1%, respectively. 2. The fertilization rates in vitro at each medium of pH 6.1, 6.4, 6.7, 7.0, 7.3, 7.6, 7.9, 8.1 were 11.8, 17.9, 32.4, 61.9, 79.5, 76.7, 53.5, 13.6%, respectively. 3. In case of ICR female x ICR male embryos, the development rate of 2-cell embryos to 4-8 cell embryos was 16.2% at normal medium, but the rate was increased to 49.3% in medium containging 10 ${\mu}$M-DETA; In case of C3H female x ICR male embryos, the development rate was 41.0% at normal medium, but the rate was increased to 71.7% at 10 ${\mu}$M-EDTA-medium.

• Clinical and Experimental Reproductive Medicine
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• 제26권2호
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• pp.127-135
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• 1999

Cryopreservation is able to store the surplus pre-embryos for freezing and furthermore thawing and transfer in a subsequent cycle. Cryopreserving cells which are maintaining their viability are the very complex process. This study has been carried out in order to find the effects of cryopreservation steps, freezing media and embryonic stages on the rates of viability and development of cryopreserved mouse embryos. Female ICR mice ($6{\sim}8$ weeks old) were induced to superovulate by sequential intraperitoneal injection of 5 IU PMSG and 5 IU hCG 48h apart. Mouse embryos were collected according to its developmental stage after the injection of hCG. Embryos were cryopreserved not only by cryoprotectant step (1 step${\sim}$4 step) but also in a variety of media (HTF, IVF medium, D-PBS) and cell stage. The results were as follows: There is no clear advantage in these freezing media of rapid method, but 4 cell and 8 cell of slow method (2, 3, 4 step) have advantage in D-PBS. The development of embryos according to cell stage become greater in 8 cell stage. In the treatment steps of cryopreservation, the development of embryo to blastocyst was similar among rapid method, but the development of 4 cell and 8 cell embryos to blastocyst according to slow method was better than rapid method.

• Clinical and Experimental Reproductive Medicine
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• 제26권1호
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• pp.9-20
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• 1999

The genetic defects in human gametes and embryos can cause adverse effects on overall reproductive events. Biopsy of embryos for preimplantation genetic diagnosis (PGD) offers a new possibility of having children free of the genetic disease. In addition, advanced embryo culture method may enhance the effectiveness of embryo biopsy for the practical application of PGD. This experimental study was undertaken to evaluate the effects of coculture on the development in vitro of biopsied mouse embryos as a preclinical model for PGD of human embryos. Embryos were obtained after in vitro fertilization (IVF) from F1 hybrid mice (C57BLfemale/CBAmale). Using micromanipulation, 1, 2, 3 or 4 blastomeres of 8-cell stage embryos were aspirated through a hole made in the zona pellucida by zona drilling (ZD) with acidic Tyrode's solution (ATS). After biopsy of blastomeres, embryos were cultured in vitro for 110 hours in Ham's F-10 supplemented with 0.4% BSA or cocultured on the monolayer of Vero cells in the same medium. The frequence of blastocyst formation were recorded, and the embryos beyond blastocyst stage were stained with 10% Giemsa to count the total number of nuclei in each embryo. There was no significant difference in the blastocyst formation between the zona intact control group and the zona drilling (ZD) only, or biopsied groups. The hatching rate of all the treatment groups except 4/8 group was significantly higher than that of control group. In all the treatment groups, there was a significant reduction in the mean cell number of embryos beyond blastocyst stage ($50.2{\pm}14.0$ in control group vs. $41.2{\pm}7.9$ in ZD, $39.3{\pm}8.8$ in 7/8, $29.7{\pm}6.4$ in 6/8, $25.1{\pm}5.7$ in 5/8, and $22.1{\pm}4.3$ in 4/8 groups, p<0.05). When the same treatments were followed by coculture with Vero cells, a similar pattern was seen in the blastocyst formation and the hatching rate. However, in all the treatment groups, there was a significant increase in the mean cell number of embryos beyond blastocyst stage with coculture, compared with the parallel groups without coculture. In the cleavage rate of biopsied blastomeres cultured for 110 hours after IVF, there was no significant difference between coculture and non-coculture groups (87.2% vs. 78.7%). However, the mean cell number of embryos developed from the biopsied blastomeres was significantly higher in coculture group ($11.5{\pm}4.7\;vs.\;5.9{\pm}1.9$, p<0.05). In conclusion, biopsy of mouse embryos after ZD with ATS is a safe and highly efficient method for PGD, and coculture with Vero cells showed a positive effect on the development in vitro of biopsied mouse embryos and blastomeres as a preclinical model for PGD of human embryos.